Printer Friendly

Hip dysplasia in the skeletally mature patient.

According to the Center for Disease Control, 25% of Americans will experience symptomatic hip arthritis during their lifetimes, and it has been estimated that 20% to 50% of disease burden is secondary to acetabular dysplasia.

Hip dysplasia refers to an abnormality in development, such as in size, shape, or organization, of the femoral head, acetabulum, or both. (1) These changes may lead to increased contact pressures on the joint and ultimately to hip arthrosis. (2-6) However, before the development of frank degenerative changes, many patients become symptomatic secondary to abnormal hip biomechanics, hip instability, impingement, or labral and chondral pathologies. (2-5) These processes arise from increased and abnormal forces across the joint with resultant shear forces causing pathologic changes. Changes classically appear at the anterolateral region of the acetabulum, the posterior region of the femoral head, or the femoral head and neck junction. (2)

Eventually, the mechanical hip dysfunction from dysplasia leads to early hip degeneration and osteoarthritis. (6) It has been suggested that there is a direct correlation between the onset of radiographically determined degenerative joint disease and the amount of acetabular dysplasia present. (2,7) Neonatal hip instability has been associated with a 2.6 times increased risk for total hip replacement in young adulthood in comparison to stable hips. (8) And, one quarter of hip replacements performed in patients aged 40 years or younger are due to underlying hip dysplasia. (9)

Hip dysplasia may be a primary process caused by congenital or developmental abnormalities. It has been well established that there is some genetic component to hip dysplasia. (10-16) A positive family history for developmental hip dysplasia may be found in 12% to 33% of patients who have DDH. (13,15,17-20) One study reported a tenfold increase in the incidence of DDH among the parents of index patients and a sevenfold increase among siblings compared with the incidence in the general population. (19) Another study found that over 50% of patients requiring periacetabular osteotomy for hip dysplasia had a family history of hip dysplasia, and over 40% were first degree relatives. (21) In addition, a number of secondary causes of dysplasia exist, including neuromuscular diseases, slipped capital femoral epiphysis, Perthes disease, trauma, or epiphyseal dysplasias.

Normal Hip Development

The formation of the hip joint begins at the seventh week of gestation. The acetabulum and the femoral head develop from the same group of mesenchymal stem cells. (22-24) At the seventh week of gestation, a cleft develops in the precartilaginous cells. This cleft defines the acetabulum from the femoral head. By the 11th week of gestation, the hip joint is fully formed, but acetabular development continues throughout intrauterine life, particularly by means of growth and development of the labrum. (23-25)

In the normal hip at birth, the femoral head is deeply seated in the acetabulum and held within the confines of the acetabulum by the surface tension of the synovial fluid. It is extremely difficult to dislocate a normal infant hip, even after incising the hip joint capsule. (26,27) Hips in newborns with developmental dysplasia are not just normal hips with capsular laxity; they are structurally abnormal.

In the infant, the entire proximal end of the femur, including the greater trochanter, the intertrochanteric zone, and the proximal femur, is composed of cartilage. Between the fourth and seventh months of life, the proximal femoral ossification center appears. The bony centrum and its anlage continue to enlarge until adulthood. The proximal femur and the trochanter enlarge by appositional cartilage cell proliferation. (28)

The growth areas in the proximal femur are the physeal plate, the growth plate of the greater trochanter, and the femoral neck isthmus. (28) A balance among the growth rates of these centers accounts for the normal configuration of the proximal femur, the relationship between the proximal femur and the greater trochanter, and the overall width of the femoral neck. Growth of the proximal femur is affected by the pull of muscles inserting on the proximal femur, forces being transmitted across the hip joint with weightbearing, normal joint nutrition, normal joint circulation, and normal muscle tone. (28-31)

Normal development and subsequent functioning of the hip joint requires a balanced growth of the acetabular and triradiate cartilages as well as a concentrically reduced femoral head. Experimental animal studies and clinical findings in humans with unreduced hip dislocations suggest that the main stimulus for the concave shape of the acetabulum is the presence of a spherical femoral head. (32,33) Harrison and coworkers determined that the acetabulum failed to deepen in area and depth after femoral head excision in rats. (33) He also demonstrated atrophy and degeneration of the acetabular cartilage. (32)

The acetabulum is deepened by the natural pressure from the developing femoral head on the acetabulum. (32-35) The depth of the acetabulum is further enhanced at puberty by the development of three secondary ossification centers. (27,33,36) The os acetabulum develops in the thick cartilage that separates the acetabular cavity from the pubis. The os acetabulum is the epiphysis of the pubis and forms the anterior wall of the acetabulum. The epiphysis of the ilium, the acetabular epiphysis, forms a major portion of the superior edge of the acetabulum. A third small epiphysis also forms in the ischial region and contributes to its normal growth.

Anatomy

Dysplastic hips often share anatomic abnormalities. The classic dysplastic acetabulum is typically shallow, lateralized, and anteverted. (2,37-42) The coverage is typically deficient anteriorly, laterally, and superiorly. In some cases, the entire pelvis may be underdeveloped. The dysplastic femur has a small femoral head with excessive femoral neck anteversion and a short neck with an increased neck shaft angle. (2,43-45) The greater trochanter is often displaced posteriorly and the lesser trochanter assumes a relatively more anterior position. The femoral canal is usually narrow and has been described as a "pipe stem" femur (Fig. 1).

As these bony changes develop, the soft tissues also become abnormal. The abductor muscles become oriented more transversely and therefore function less efficiently. The psoas tendon hypertrophies and the hip capsule thickens. In addition, the hamstrings, adductors, and rectus femoris muscles all shorten.

These pathologic changes result in abnormalities within the hip joint. As the hip joint becomes less stable, the acetabular labrum initially hypertrophies in an attempt to maintain the femoral head within the acetabulum. (3) Similarly, the ligamentum teres hypertrophies. If chronic shear stress persists, the labral soft tissue compensation will likely fail, and the labrum can be torn away from the acetabular rim, resulting in increased contact forces on the cartilage surfaces (Fig. 2). (3,5,46-50)

[FIGURE 1 OMITTED]

[FIGURE 2 OMITTED]

Ultimately, these pathologic processes lead to decreased contact area between the femoral head and the acetabulum and lateralization of the center of rotation of the hip. This results in an increased body-weight arm and resultant higher forces transmitted through a smaller surface area, culminating in degenerative hip changes.

Natural History

Studies have demonstrated that acetabular dysplasia leads to degenerative changes over time, likely secondary to mechanical factors and related to increased contact stresses. (51-55) Reduced acetabular size and obliquity create shearing forces on the articular cartilage. These forces lead to chronic overload of the anterior and anterolateral acetabular rim. Eventually, the articular cartilage of the anterior acetabulum and the femoral head fail. Previous reports demonstrate that radiographic degenerative joint disease correlates with the magnitude and length of the excessive pressure. (54,56)

In 2011, Ross and colleagues published their results of arthroscopy in 73 dysplastic hips undergoing periacetabular osteotomies. A labral tear or chondral degeneration was found in 86% of hips, and 63% of hips demonstrated a hypertrophied labrum. Only 7% of hips were without intraarticular pathology. Labral disease was most common in the anterior (81%) and superolateral (67%) labrochondral junctions. Over two-thirds of patients were found to have acetabular chondromalacia. Acetabular chondral lesions were primarily located at the anterior (76%) and superolateral (84%) labrochondral junctions. Femoral head chondromalacia was seen in only 11% of hips. Sixty-three percent of patients were found to have intraarticular pathology sufficient to require surgical treatment. (57)

While there is considerable evidence that radiographic acetabular dysplasia leads to secondary degenerative joint disease, (15,58) there are no predictive radiographic parameters. Cooperman and associates (1983) studied 32 dysplastic hips with lateral center edge angles of less than 20[degrees] for more than 20 years in order to determine the natural history of acetabular dysplasia. The investigators found that all patients eventually developed radiographic evidence of degenerative joint disease. Moreover, they determined that none of the conventional radiographic parameters used to describe hip dysplasia were able to predict the rate of the degenerative joint disease. (54)

Patient Presentation

Patients who present with hip pain require a thorough history and physical examination to elucidate the source of their symptoms. Patient factors, including age, overall health, activity level, occupation, and illicit habits, should be identified. In addition, a hip specific history should be taken, including family history of hip problems, any known previous hip disease, and any history of prior hip surgery. Previous hip disease or related treatments, such as childhood and adolescent hip problems, previous hip surgery, hip trauma, and osteonecrosis, may indicate a secondary dysplasia.

Pain characteristics need to be thoroughly evaluated. Patients with hip dysplasia may initially present with mild peritrochanteric pain reflecting abductor fatigue, an almost universal finding in pre-arthrotic hip dysplasia in the mature adult. (59) Commonly, patients with dysplasia will have groin pain in the affected hip that is worsened with activity. (59)

Similarly, the pattern of symptoms may help elucidate the nature of the dysplasia. Pain worse with weightbearing and activity may indicate underlying joint pathology. Pain with flexion positions or prolonged periods of sitting may commonly be associated with femoroacetabular impingement (FAI). The sensation of locking or catching in the affected joint may indicate intraarticular mechanical problems, such as a labral tear, chondral flap, or loose body.

Nunley and colleagues examined 57 patients with known hip dysplasia. Ninety-seven percent of their patients reported an insidious onset of hip pain without an inciting event. Seventy-two percent of these patients localized their pain to the groin. Eighty-eight percent of patients noted activity related pain with 81% reporting that their symptoms were exacerbated by walking and 80% while running. At least one mechanical symptom was reported by 80% of their patients. Almost half of the studied patients reported a limp. Night pain was also found in more than half of the patients. (60)

Physical Exam

The physical examination of the patient with suspected hip dysplasia should take into account general condition and body habitus, the patient's sitting posture, and their gait pattern. It is also important to assess for a leg length discrepancy. Standing measurements will allow an assessment of pelvic balance and are therefore considered the best way to assess a leg length discrepancy. (59,61)

Resting lower extremity rotation should be assessed with the patient lying supine on the exam table. Normal lower extremity rotation is between 10[degrees] and 30[degrees] of external rotation. Abnormal rotation may result from abnormal acetabular version, abnormal femoral version, or femoral head-neck abnormalities. (59)

Hip range of motion testing is essential for not only diagnosis but also for pre-procedure planning. (62) The examiner should steady the pelvis with one hand while performing range of motion testing, including hip flexion and internal and external rotation both in 90[degrees] of flexion and full extension. In contrast to classic FAI, which may demonstrate restricted hip flexion and internal rotation, patients with classic dysplasia will generally demonstrate normal hip flexion and normal internal rotation. (47,63,64)

Some special tests may help elucidate the nature of the hip pathology. The anterior impingement test is a special maneuver that is indicative of disorders of the anterior acetabular rim. (65,66) It is very sensitive for a range of anterior hip lesions, including labral tears and rim fractures, but fairly non-specific for intra-intrarticular disease and joint irritability. (65) The patient is placed supine, and the affected extremity is passively flexed, adducted, and internally rotated. The test is considered positive if this maneuver reproduces the patient's pain. Nunley reported that 97% of the patients in his study had a positive impingement sign. (60)

The apprehension test is another special maneuver that is useful to assess for anterior hip instability, though it may be positive in patients with labral lesions as well. It is performed by having the patient lie supine on the table. The affected extremity is extended and rapidly externally rotated. The test is considered positive if it elicits apprehension or anterior hip pain.

Finally, patients should be assessed for hip abductor weakness. The Trendelenburg sign is elicited if the patient leans away from the affected extremity during single legged stance on the affected extremity. Nunley reported that 38% of patients in his study had a positive Trendelenburg sign. (60) Alternatively, abductor strength can be tested by having the patient lie on his unaffected side and asking him to abduct the leg against resistance.

Radiology

The evaluation of a patient with suspected hip dysplasia is confirmed with imaging. The radiographic features of adult hip dysplasia may range from subtle acetabular dysplasia to complete dislocation of the femoral head from the native acetabulum. The goals of imaging are to assess the structural anatomy of the hip, determine the congruency of the articulation, examine the integrity of the joint space, and to assess the soft tissues. (64) Table 1 describes the commonly used radiographic parameters and measurements used in the diagnosis and categorization of hip dysplasia.

The anterior-posterior (AP) view of the pelvis is the single most important view for defining acetabular dysplasia. It allows for the assessment of acetabular coverage of the femoral head, femoral head sphericity, (67) the contour of the femoral head-neck junction, the height of the greater trochanter, position of the joint center, the joint space, and Shenton's line.

Lateral radiographs allow better definition of the osseous anatomy of the proximal femur, anterior and posterior joint spaces, and the acetabular rim. Lateral radiographs include the cross table lateral and frog lateral. Also among the lateral views is the false profile view. (68) This image is obtained by having the patient stand with their foot parallel to the radiographic plate and their pelvis rotated 65[degrees] relative to the film. This view constitutes a true lateral view of the acetabulum. It allows measurement of the anterior coverage of the acetabulum, and may also allow better detection of the degenerative changes that tend to begin at the anterior aspect of the joint.

Computer tomography (CT) is a complementary study in evaluating hip dysplasia when dysplastic signs have been recognized on plain films and surgical correction is anticipated. It allows reliable measurements of acetabular coverage, femoral neck anteversion, and the appearance and position of the femoral head. (69) It also allows better characterization of osseous impingement lesions. (6,64)

Magnetic resonance imaging (MRI) is not routinely necessary in hips with obvious structural abnormalities. It may assist in the evaluation of a painful hip in the absence of structural osseous abnormalities and can be useful in the diagnosis of osteonecrosis of the femoral head, stress fracture, neoplasm, or infection. MRI and MRI arthrogram are useful adjuvants to evaluate the labrum and should be obtained in patients with mechanical symptoms.

Classification

Two classification systems are routinely used in describing dysplastic hips. The Tonnis classification groups hips by the degree of secondary osteoarthritis changes. (70) It is useful in planning for osteotomies but is more frequently utilized for research purposes (Table 2).

The Crowe classification describes the degree of femoral head subluxation or dislocation (Table 3). (71) The classification is determined by measuring the vertical distance between the inter-teardrop line and the junction between the femoral head and the medial edge of the neck. The amount of subluxation is the ratio between this distance and the vertical diameter of the normal femoral head. This classification system can be used to guide treatment algorithms for patients being considered for total hip arthroplasty.

Treatment

Hip Arthroscopy

Hip arthroscopy is an option for the treatment of mild hip dysplasia. This technique can address mechanical symptoms, loose bodies, labral tears, chondral defects, and synovial disease (Fig. 2). However, it is limited in that it does not address the osseous abnormalities of the dysplastic hip that are the underlying cause of the mechanical symptoms.

Several investigators have looked at the outcomes of dysplastic hips treated with hip arthroscopy. Byrd and Jones published a report in 2003 of 48 patients who underwent hip arthroscopy for intraarticular pathology and were retrospectively determined to have acetabular dysplasia. The investigators found that 67% of the hips had labral lesions, and 60% had chondral lesions that were addressed at the time of surgery. Patients were followed for an average of 27 months, and the investigators found that all patients had improved Modified Harris Hip Scores at final follow-up. (72)

In contrast, Parvizi and colleagues published a report in 2009 in which they described the outcomes in 36 dysplastic hips treated with hip arthroscopy for intraarticular pathology. At an average of 3.5 years of follow-up, they found that two-thirds of the patients had failure to control their symptoms, and that 44% of their study population went on to require additional open procedures. They did note that the patients largely demonstrated improved functional scores at 6 weeks; however, these improvements deteriorated with time. (73)

The deterioration of function after hip arthroscopy in dysplastic hips is likely multifactorial. (5,72,74,75) Some investigators argue that the pain relief following labral debridement may mask the underlying mechanical abnormalities, resulting in progressive damage to the anterolateral acetabular articular cartilage. (73,75-77) Moreover, the hypertrophied labrum seen in hip dysplasia is protective against microinstability. Labral debridement performed during hip arthroscopy may actually allow for increased microinstability leading to further articular degeneration. (3,76) Support for this theory can be seen in the progression of osteoarthritis and anterolateral migration of the femoral head which has been described following arthroscopic labral debridement in hips with underlying dysplasia. (73,75,76)

While hip arthroscopy alone has limited applicability in the treatment of hip dysplasia, it is a useful adjuvant treatment when combined with bony reconstructive procedures. (5,6,74,76) Acetabular dysplasia typically results in intraarticular pathology, and hip arthroscopy may provide an opportunity to address this pathology. (57,77) Kim and colleagues published their results of combined hip arthroscopy and periacetabular osteotomy. They found that 88% of their patients had a labral lesion. All patients with labral lesions underwent arthroscopic labral debridement at the time of arthroscopy. The mean Harris Hip Score improved from 72.4 preoperatively to 94 at a mean of 74 months. (78)

Osteotomies

Osteotomies are useful in the treatment of hip dysplasia as they can address the underlying morphologic abnormality. They can reorient the articular surfaces of the hip joint and allow load transmission through a broader surface area, subjecting the joint to less force. (79,80) Osteotomies can also medialize the center of hip rotation and as a result decrease the joint reactive forces. (80) These changes can reduce pain, protect the articular cartilage, and improve the functional arc of motion. (80,81) These procedures are generally indicated in young patients with symptomatic hip dysplasia without excessive proximal migration of the hip center of rotation, who have preserved range of motion and no more than mild degenerative changes.

Osteotomies about the hip joint can be carried out at the acetabulum, at the proximal femur, or using some combination of both. Pelvic osteotomies address the location of the primary pathology. They correct the major anatomic abnormality and do not create a secondary deformity, which can affect future reconstructive procedures. (82) The femoral osteotomy can be added if significant femoral deformity exists; however, it is rarely indicated as an isolate procedure in patients with acetabular dysplasia. (82,83)

Pelvic Osteotomies

Pelvic osteotomies can be categorized into two types: reconstructive and salvage. Reconstructive osteotomies are intended to restore normal hip anatomy and biomechanics. They improve symptoms and possibly prevent degenerative changes. These types of osteotomies require a hip joint in which the femoral head and the acetabulum are congruent. Salvage osteotomies are used to relieve pain when the articular surface congruency cannot be restored. These osteotomies are performed in patients who have a hip joint in which the femoral head and the acetabulum are not the same shape (Fig. 3).

Various periacetabular osteotomies have been developed to reorient the hyaline cartilage of the hip in mature patients. Salter's innominate osteotomy was first used in mature hips more than 50 years ago. (84) It proved useful in the treatment of mild dysplasia but was inconsistent in major acetabular reorientation. More consistent major acetabular reorientation was introduced independently in Germany (85) and Japan (86) with spherical osteotomies. This technique allows excellent femoral head coverage, but medialization of the joint center can be difficult. Other complex osteotomies were subsequently introduced by Tonnis (87) and Steel. (88)

In 1988, Ganz and colleagues introduced the Bernese periacetabular osteotomy. (81) This procedure, which is also known as a "Ganz osteotomy," allows both redirection of the acetabulum and medialization of the hip joint center. The fundamental goal of this procedure is to correct the acetabular insufficiency and improve femoral head coverage by repositioning the weightbearing surface laterally and anteriorly. (80,81) Secondary goals include improved hip stability and medialization of the hip center of rotation. (80,81)

[FIGURE 3 OMITTED]

The ideal patient for these procedures is one with a symptomatic structural abnormality, a congruent joint, and the absence of advanced secondary arthritis. These patients also need to have a well-maintained hip range of motion. These osteotomies are contraindicated in patients with excessive posterior wall coverage. These patients require a surgical dislocation in order to adequately address their deformities. (80,81) Patients with advance cartilage degeneration anteriorly also should not undergo this procedure as the degenerative area will wind up in the weightbearing zone after osteotomy.

There are numerous advantages to the periacetabular osteotomy as a treatment for hip dysplasia. The Ganz osteotomy is generally performed through a modified Smith Peterson approach, and this abductor sparing dissection through a single incision decreases the risk of postoperative gait abnormalities. (80,81,89) The osteotomy utilizes straight, reproducible, extra-articular cuts that preserve the posterior column and do not change the shape of the true pelvis. The osteotomy also allows major multi-planar corrections, including lateral and anterior rotation and medialization of the hip joint. This approach preserves the acetabular fragment blood supply, provides reliable healing, and allows for accelerated rehabilitation. (80,81,89) Most importantly, this intervention is a joint preserving treatment.

The Ganz osteotomy is performed from the inner aspect of the pelvis and generally consists of three cuts: a partial osteotomy of the ilium, a complete osteotomy of the pubis, and a biplanar osteotomy of the ilium. (81) The osteotomized acetabulum is then displaced medially, rotated anteriorly, and rotated laterally. The osteotomy is then secured with several screws. Postoperative radiographs are used to assess the adequacy of the correction.

Acetabular osteotomies address the underlying bony abnormality, but most patients will have intraarticular pathology at the time of presentation. (57,76,78,82,86) Most investigators recommend opening the joint and evaluating for labral lesions as well as impingement between the anterior femoral neck and anterior acetabulum. (74,77,90-93) An anterior arthrotomy performed in associated with a PAO allows resection of anterior labral tears and limited femoral neck osteoplasty. However, joint exposure is limited unless an extensive abductor dissection is performed. (78) Other investigators have suggested either simultaneous or staged hip arthroscopy to assess and treat the intraarticular pathology. (76,78)

Several studies have reported on outcomes after periacetabular osteotomies. (60,79,80,89,94-97) In 2011, Nunley and colleagues reported their outcomes with PAOs in 65 hips with symptomatic hip dysplasia at an average of 27 months. They found an improvement in mean Modified Harris Hip Scores from 66.4 to 91.7 at final follow-up. Only one hip in their series required conversion to a total hip arthroplasty. One hip required revision for symptomatic femoral-acetabular impingement. Postoperative radiographs demonstrated consistent correction, including improved femoral head coverage and improved acetabular inclination. (60)

In the longest follow-up study published to date, the Bern group reported their long-term outcomes with the Bernese periacetabular osteotomy. (97) When evaluating the first 75 hips in which they performed the procedure at the 20-year follow-up, they found that 40% had gone on to require total hip arthroplasty or fusion at an average of 12 years after the index procedure. The group also identified several factors as predictive of a poor outcome: older age at surgery, positive anterior impingement test, limp, higher osteoarthritis grade, and postoperative extrusion index.

Though results with the Ganz osteotomy tend to be favorable, complications can arise. Excess posterior coverage can be caused by excessive anteversion of the osteotomy. (95,98) This can lead to posterior acetabular impingement and limited extension and external rotation. The osteotomy can also be malpositioned anteriorly, resulting in an acetabular index of less than zero, which may result in secondary anterior impingement. (98)

In patients with severe acetabular dysplasia that do not have a congruent joint, but have minimal arthritic changes, a redirectional osteotomy cannot correct their abnormal morphology. These patients may be candidates for a salvage osteotomy. The two most commonly performed salvage osteotomies are shelf (99) procedures and the Chiari osteotomy. (100)

Shelf procedures generally use corticocancellous graft to augment the anterolateral portion of the acetabulum. (99) The graft is inserted into a slot created above the acetabulum and acts as a buttress to increase joint stability and increase the weightbearing surface of the acetabulum. This procedure does not change the relationship of the femoral head to the true acetabulum, nor does it medialize the hip center of rotation.

The Chiari osteotomy is recommended for patients with inadequate femoral head coverage and an incongruous joint. (100-102) An osteotomy is made above the acetabulum and extends into the sciatic notch. By abducting the hip, the distal portion of the osteotomy moves medially, shifting the ilium laterally beyond the edge of the acetabulum. The procedure thus medializes the hip center. The interposed capsule undergoes metaplasia and becomes fibrocartilage over time.

Femoral Osteotomies

Proximal femoral osteotomies have been used in the treatment of hip dysplasia for approximately a century with a varus osteotomy to correct the coax valga and a distal transfer of the greater trochanter to correct for trochanteric overgrowth. (83) However, proximal femoral osteotomies along are rarely useful in stabilizing hips with acetabular dysplasia in skeletally mature patients. They are useful when the femur is the primary source of deformity or when the pelvic osteotomy alone provides insufficient correction. (83,103)

In order to perform an isolated proximal femoral osteotomy, several criteria need to be met: the osteotomy must completely correct the deformity, the patients must have a functional arc of motion, the joint needs to congruent, and placing the hip in the position of proposed correction should provide comfort to the patient. (83) This situation is generally only found in patients with coax valga and mild acetabular dysplasia.

Hip Arthrodesis

In patients with severe unilateral hip dysplasia and who are poor candidates for osteotomies or total hip replacement, an arthrodesis may be considered. However, currently, these procedures are rarely indicated. Arthrodesis may provide good pain relief for patients with severe unilateral disease; however, this procedure will limit a patient's physical activities and can lead to progressive degenerative changes in the ipsilateral knee and lower back. (104-107)

The ideal position for hip arthrodesis is neutral abduction, external rotation of 0[degrees] to 30[degrees], and 20[degrees] to 25[degrees] of flexion. It is essential to avoid abduction and internal rotation in order to minimize excessive lumbar spine and contralateral knee motion. (108,109) Contraindications to performing a hip arthrodesis include morbid obesity, systemic arthritis, contralateral hip dysfunction, lumbosacral spine disease, or ipsilateral knee abnormalities. (110)

Pelvic Support Osteotomy

Another option for treatment of severe hip dysplasia is a resection of the femoral head with valgus-producing pelvic support osteotomy (Fig. 4). (111) This treatment is generally reserved for patients with severe pain and low functional demands, such as those with underlying neuromuscular disorders or poor medical conditions.

The goals of this procedure are to create and abduction and extension effect in the femur at the level of the ischium to increase the range of abduction, support the femur on the pelvis, to reduce lumbar lordosis, and to prevent a Trendelenburg limp by tightening the gluteus medius muscle as the distance of the greater trochanter from the pelvis is increased. (111-113) The disadvantages of this procedure include the limb length inequality it produces, overall lower extremity weakness, the need for ambulatory aids, increased oxygen consumption with ambulation, and decreased gait velocity. (112,114)

A Japanese group reported on their 20-year follow-up of 53 patients who had undergone 58 pelvic support osteotomies for osteoarthrosis of a dysplastic hip. Thirty-five percent of these patients underwent total hip arthroplasty at an average of 14 years after the index procedure (range: 7 to 24 years), and only one patient required corrective varus osteotomy to pass the stem. The Kaplan Meier's survivorship was 66% at 10 years and decline to 38% and 19% at 15 and 20 years, respectively. (103)

Total Hip Arthroplasty

Despite the availability the recent advances in joint-preserving techniques, many patients with hip dysplasia present with advanced degenerative disease that is not amenable to joint preservation surgery. (9,115) Because of the anatomic abnormalities associated with hip dysplasia and the younger mean age of patients with this diagnosis who go on to require arthroplasty, special considerations need to be made when considering total hip arthroplasty (THA) in this population. In the very young patient, the long-term implications of performing a THA make secondary goals like bone and muscle preservation and prolonged implant durability almost as important as the primary goal of pain relief. (115)

[FIGURE 4 OMITTED]

Abductor deficiency is a common problem in patients with severe hip dysplasia. As the greater trochanter becomes displaced posteriorly and the neck shaft angle decreases, the abductor lever arm becomes oriented more transversely. This abductor deficiency can result in serious complications after a THA, including high rates of dislocation (116) and chronic limp. (115)

Deficient acetabular bone may limit the surgeon's ability to place the acetabular component fully on native bone in the true acetabular region (Fig. 5). Three common alternative methods to reconstruct dysplastic acetabuli have been described: augmentation with bone grafting, a high hip center, or medialization of the cup.

Acetabular augmentation with structural grafting of the deficient acetabulum in combination with placing the component in its anatomic position has some desirable features. Autograft bone is readily available by using the patient's own femoral head, the hip center can be restored to a biomechanically normal position, and bone grafting may increase bone stock. (117,118) There are also disadvantages to this technique, including that bone grafting increases the complexity of the procedure, and when a large amount of the component is supported by the graft, there is a risk of long-term graft resorption and collapse, leading to cup failure. (119)

[FIGURE 5 OMITTED]

Purposefully creating a high hip center or placing the component superiorly allows the component to be covered more completely by native bone, which facilitates biologic fixation and avoids the need for bone grafting. (120,121) It also requires smaller acetabular components with thinner polyethylene liners, does not increase acetabular bone stock, affords a limited amount of leg lengthening, and leads to abnormal hip biomechanics. The high hip center needs to be high and medial, or it will fail early.

[FIGURE 6 OMITTED]

A third alternative for acetabular reconstruction is medialization of the acetabular component by internally overreaming or deliberate fracture of the medial wall of the acetabulum. (122,123) This technique provides increased lateral coverage of the acetabular component by native iliac bone and decreases joint reactive forces through medialization of the hip center of rotation. Its main disadvantages include the loss of medial bone stock and the risk of early catastrophic acetabular component migration.

For the femoral component, a proximally coated monolithic stem can be used in mild dysplasia. However, for more marked deformities, extensively coated stems or modular stems may be required. Moreover, a subtrochanteric or metaphyseal osteotomy may be required in more severely dysplastic cases. A subtrochanteric osteotomy allows both shortening and correction of the rotational abnormalities while preserving the metaphysis (Fig. 6). (124-126) The resected bone may then be used as an onlay autograft.

Several studies have addressed the outcomes in patients undergoing total hip arthroplasty for hip dyspalsia. (123,127-131) Pain relief in patients with hip dysplasia undergoing total hip arthroplasty parallels the excellent results of total hip arthroplasty in the general population. (115,123,127-129) Notable overall improvements in hip scores were also reported in most series. (127-131)

Patients with very stiff hips preoperatively may have residual postoperative stiffness. Functional results tend to be excellent in patients with Crowe I and II dysplasia but are less good in patients with Crowe III and IV disease. Patients with Crowe III and IV dysplasia tend to have a persistent limp with a waddling gait, as well as a higher rate of aseptic loosening and mechanical failure than the general population undergoing total hip arthroplasty.

[FIGURE 7 OMITTED]

Conclusion

The treatment of hip dysplasia in adult patients is based on the degree of dysplasia and the amount of concomitant arthritis. Patients with mild dysplasia who are asymptomatic can be observed. Those with mechanical symptoms alone can undergo arthroscopy with close follow-up. Patients with moderate to severe dysplasia and minimal arthritis are candidates for reconstruction. Those patients with moderate to severe arthritis can undergo a salvage procedure, such as arthrodesis or pelvic support. However, a vast majority of these patients are best served with a total hip arthroplasty (Fig. 7).

Disclosure Statement

None of the authors have a financial or proprietary interest in the subject matter or materials discussed, including, but not limited to, employment, consultancies, stock ownership, honoraria, and paid expert testimony.

Caption: Figure 1 The classic dysplastic acetabulum is typically shallow, lateralized, and anteverted with deficient coverage anteriorly, laterally, and superiorly. The dysplastic femur has a small femoral head with excessive femoral neck anteversion and a short neck with an increased neck shaft angle.

Caption: Figure 2 Arthroscopic images from a patient with hip dysplasia demonstrating the classic hypertrophied labrum (A) and labral tear at the acetabular rim (B).

Caption: Figure 3 Flowchart of pelvic osteotomies.

Caption: Figure 4 A 14-year-old male with neglected congenital hip dislocation (A). After proximal femoral valgus osteotomy and distal femoral varus osteotomy with lengthening (B).

Caption: Figure 5 Deficient acetabular bone may limit the surgeon's ability to place the acetabular component fully on native bone in the true acetabular region.

Caption: Figure 6 A, A patient with bilateral Crowe 4 hip dysplasia. B, Status bilateral total hip arthroplasties with modular stems and subtrochanteric shortening osteotomies.

Caption: Figure 7 Flowchart of the approach to hip dysplasia in the skeletally mature individual.

References

(1.) Guille JT, Pizzutillo PD, MacEwen GD. Development dysplasia of the hip from birth to six months. J Am Acad Orthop Surg. 2000 Jul-Aug;8(4):232-42.

(2.) Sanchez-Sotelo J, Trousdale RT, Berry DJ, Cabanela ME. Surgical treatment of developmental dysplasia of the hip in adults: I. Nonarthroplasty options. J Am Acad Orthop Surg. 2002 Sep-Oct;10(5):321-33.

(3.) Crawford MJ, Dy CJ, Alexander JW, et al. The 2007 Frank Stinchfield Award. The biomechanics of the hip labium and the stability of the hip. Clin Orthop Relat Res. 2007 Dec;465:16-22.

(4.) Felson DT. Risk factors for osteoarthritis: understanding joint vulnerability. Clin Orthop Relat Res. 2004 Oct;(427 Suppl):S16-21.

(5.) Wenger DE, Kendell KR, Miner MR, Trousdale RT. Acetabular labral tears rarely occur in the absence of bony abnormalities. Clin Orthop Relat Res. 2004 Sep;(426):145-50.

(6.) Clohisy JC, Beaule PE, O'Malley A, et al. AOA symposium. Hip disease in the young adult: current concepts of etiology and surgical treatment. J Bone Joint Surg Am. 2008 Oct;90(10):2267-81.

(7.) Murphy SB, Ganz R, Muller ME. The prognosis in untreated dysplasia of the hip. A study of radiographic factors that predict the outcome. J Bone Joint Surg Am. 1995 Jul;77(7):985-9.

(8.) Engesaeter IO, Lie SA, Lehmann TG, et al. Neonatal hip instability and risk of total hip replacement in young adulthood: follow-up of 2,218,596 newborns from the Medical Birth Registry of Norway in the Norwegian Arthroplasty Register. Acta Orthop. 2008 Jun;79(3):321-6.

(9.) Engesaeter IO, Lehmann T, Laborie LB, et al. Total hip replacement in young adults with hip dysplasia: age at diagnosis, previous treatment, quality of life, and validation of diagnoses reported to the Norwegian Arthroplasty Register between 1987 and 2007. Acta Orthop. 2011 Apr;82(2):149-54.

(10.) Hogervorst T, Eilander W, Fikkers JT, Meulenbelt I. Hip ontogenesis: how evolution, genes, and load history shape hip morphotype and cartilotype. Clin Orthop Relat Res. 2012 Dec;470(12):3284-96.

(11.) Tian W, Zhao L, Wang J, et al. Association analysis between HOXD9 genes and the development of developmental dysplasia of the hip in Chinese female Han population. BMC Musculoskelet Disord. 2012 Apr 20;13:59.

(12.) Feldman GJ, Peters CL, Erickson JA, et al. Variable expression and incomplete penetrance of developmental dysplasia of the hip: clinical challenge in a 71-member multigeneration family. J Arthroplasty. 2012 Apr;27(4):527-32.

(13.) Ortiz-Neira CL, Paolucci EO, Donnon T. A meta-analysis of common risk factors associated with the diagnosis of developmental dysplasia of the hip in newborns. Eur J Radiol. 2012 Mar;81(3):e344-51.

(14.) Heikkila E. Congenital dislocation of the hip in Finland. An epidemiologic analysis of 1035 cases. Acta Orthop Scand. 1984 Apr;55(2):125-9.

(15.) Hoaglund FT, Healey JH. Osteoarthrosis and congenital dysplasia of the hip in family members of children who have congenital dysplasia of the hip. J Bone Joint Surg Am. 1990 Dec;72(10):1510-8.

(16.) Rabin DL, Barnett CR, Arnold WD, et al. Untreated Congenital Hip Disease. A Study of the Epidemiology, Natural History, and Social Aspects of the Disease in a Navajo Population. Am J Public Health Nations Health. 1965 Feb;55:SUPPL:1-44.

(17.) Bache CE, Clegg J, Herron M. Risk factors for developmental dysplasia of the hip: ultrasonographic findings in the neonatal period. J Pediatr Orthop B. 2002 Jul;11(3):212-8.

(18.) Wynne-Davies R. Acetabular dysplasia and familial joint laxity: two etiological factors in congenital dislocation of the hip. A review of 589 patients and their families. J Bone Joint Surg Br. 1970 Nov;52(4):704-16.

(19.) Bjerkreim I, Arseth PH. Congenital dislocation of the hip in Norway. Late diagnosis CDH in the years 1970 to 1974. Acta Paediatr Scand. 1978 May;67(3):329-32.

(20.) Haasbeek JF, Wright JG, Hedden DM. Is there a difference between the epidemiologic characteristics of hip dislocation diagnosed early and late? Can J Surg. 1995 Oct;38(5):437-8.

(21.) Lee CB, Mata-Fink A, Millis MB, Kim YJ. Demographic differences in adolescent-diagnosed and adult-diagnosed acetabular dysplasia compared with infantile developmental dysplasia of the hip. J Pediatr Orthop. 2013 Mar;33(2):107-11.

(22.) Lee J, Jarvis J, Uhthoff HK, Avruch L. The fetal acetabulum. A histomorphometric study of acetabular anteversion and femoral head coverage. Clin Orthop Relat Res. 1992 Aug;(281):48-55.

(23.) Strayer LM. The Embryology of the Human Hip Joint. Yale J Biol Med. 1943 Oct;16(1):13-26.6.

(24.) Strayer LM Jr. Embryology of he human hip joint. Clin Orthop Relat Res. 1971 Jan;74:221-40.

(25.) Watanabe RS. Embryology of the human hip. Clin Orthop Relat Res. 1974 Jan-Feb;(98):8-26.

(26.) Dunn PM. The anatomy and pathology of congenital dislocation of the hip. Clin Orthop Relat Res. 1976 Sep;(119):23-7.

(27.) Ponseti IV. Morphology of the acetabulum in congenital dislocation of the hip. Gross, histological and roentgenographic studies. J Bone Joint Surg Am. 1978 Jul;60(5):586-99.

(28.) Siffert RS. Patterns of deformity of the developing hip. Clin Orthop Relat Res. 1981 Oct;(160):14-29.

(29.) Gage JR, Cary JM. The effects of trochanteric epiphyseodesis on growth of the proximal end of the femur following necrosis of the capital femoral epiphysis. J Bone Joint Surg Am. 1980 Jul;62(5):785-94.

(30.) Osborne D, Effmann E, Broda K, Harrelson J. The development of the upper end of the femur, with special reference to its internal architecture. Radiology. 1980 Oct;137(1 Pt 1):71-6.

(31.) Sugano N, Noble PC, Kamaric E, et al. The morphology of the femur in developmental dysplasia of the hip. J Bone Joint Surg Br. 1998 Jul;80(4):711-9.

(32.) Harrison TJ. The influence of the femoral head on pelvic growth and acetabular form in the rat. J Anat. 1961 Jan;95:12-24.

(33.) Harrison TJ. The growth of the pelvis in the rat; a mensural and morphological study. J Anat. 1958 Apr;92(2):236-60.

(34.) Coleman CR, Slager RF, Smith WS. The effect of environmental influence on acetabular development. Surg Forum. 1958;9:775-80.

(35.) Smith WS, Ireton RJ, Coleman CR. Sequelae of experimental dislocation of a weight-bearing ball- and socket joint in a young growing animal; gross alterations in bone and cartilage. J Bone Joint Surg Am. 1958 Oct;40-A(5):1121-7.

(36.) Weinstein SL. Natural history of congenital hip dislocation (CDH) and hip dysplasia. Clin Orthop Relat Res. 1987 Dec;(225):62-76.

(37.) Salter RB. Etiology, pathogenesis and possible prevention of congenital dislocation of the hip. Can Med Assoc J. 1968 May 18;98(20):933-45.

(38.) Salter RB. Role of innominate osteotomy in the treatment of congenital dislocation and subluxation of the hip in the older child. J Bone Joint Surg Am. 1966 Oct;48(7):1413-39.

(39.) Lloyd-Roberts GC, Harris NH, Chrispin AR. Anteversion of the acetabulum in congenital dislocation of the hip: a preliminary report. Orthop Clin North Am. 1978 Jan;9(1):89-95.

(40.) Murphy SB, Kijewski PK, Millis MB, Harless A. Acetabular dysplasia in the adolescent and young adult. Clin Orthop Relat Res. 1990 Dec;(261):214-23.

(41.) Wientroub S, Boyde A, Chrispin AR, Lloyd-Roberts GC. The use of stereophotogrammetry to measure acetabular and femoral anteversion. J Bone Joint Surg Br. 1981 Aug;63-B(2):209-13.

(42.) Mast JW, Brunner RL, Zebrack J. Recognizing acetabular version in the radiographic presentation of hip dysplasia. Clin Orthop Relat Res. 2004 Jan;(418):48-53.

(43.) Doudoulakis JK, Cavadias A. Open reduction of CDH before one year of age. 69 hips followed for 13 (10-19) years. Acta Orthop Scand. 1993 Apr;64(2):188-92.

(44.) Sanchez-Sotelo J, Berry DJ, Trousdale RT, Cabanela ME. Surgical treatment of developmental dysplasia of the hip in adults: II. Arthroplasty options. J Am Acad Orthop Surg. 2002 Sep-Oct;10(5):334-44.

(45.) Perry KI, Berry DJ. Femoral considerations for total hip replacement in hip dysplasia. Orthop Clin North Am. 2012 Jul;43(3):377-86.

(46.) Beck M, Kalhor M, Leunig M, Ganz R. Hip morphology influences the pattern of damage to the acetabular cartilage: femoroacetabular impingement as a cause of early osteoarthritis of the hip. J Bone Joint Surg Br. 2005 Jul;87(7): 1012-8.

(47.) Beck M, Leunig M, Parvizi J, et al. Anterior femoroacetabular impingement: part II. Midterm results of surgical treatment. Clin Orthop Relat Res. 2004 Jan;(418):67-73.

(48.) Ito K, Leunig M, Ganz R. Histopathologic features of the acetabular labrum in femoroacetabular impingement. Clin Orthop Relat Res. 2004 Dec;(429):262-71.

(49.) Harris WH, Bourne RB, Oh I. Intraarticular acetabular labrum: a possible etiological factor in certain cases of osteoarthritis of the hip. J Bone Joint Surg Am. 1979 Jun;61(4):510-4.

(50.) McCarthy JC, Noble PC, Schuck MR, et al. The Otto E. Aufranc Award: The role of labral lesions to development of early degenerative hip disease. Clin Orthop Relat Res. 2001 Dec;(393):25-37.

(51.) Milgram JW. Morphology of untreated bilateral congenital dislocation of the hips in a seventy-four-year-old man. Clin Orthop Relat Res. 1976 Sep;(H9):112-5.

(52.) Fairbank JC, Howell P, Nockler I, Lloyd-Roberts GC. Relationship of pain to the radiological anatomy of the hip joint in adults treated for congenital dislocation of the hip as infants: a long-term follow-up of patients treated by three methods. J Pediatr Orthop. 1986 Sep-Oct;6(5):539-47.

(53.) Malvitz TA, Weinstein SL. Closed reduction for congenital dysplasia of the hip. Functional and radiographic results after an average of thirty years. J Bone Joint Surg Am. 1994 Dec;76(12):1777-92.

(54.) Cooperman DR, Wallensten R, Stulberg SD. Acetabular dysplasia in the adult. Clin Orthop Relat Res. 1983 May;(175):79-85.

(55.) Harris WH. Etiology of osteoarthritis of the hip. Clin Orthop Relat Res. 1986 Dec;(213):20-33.

(56.) Wiberg G. Studies on dysplastic acetabula and congenital subluxation of the hip joint: With special reference to the complication of osteoarthritis. Acta Chir Scand. 1939;58(suppl):7-135.

(57.) Ross JR, Zaltz I, Nepple JJ, et al. Arthroscopic disease classification and interventions as an adjunct in the treatment of acetabular dysplasia. Am J Sports Med. 2011 Jul;39 Suppl:72S-8S.

(58.) Hoaglund FT, Yau AC, Wong WL. Osteoarthritis of the hip and other joints in southern Chinese in Hong Kong. J Bone Joint Surg Am. 1973 Apr;55(3):545-57.

(59.) Sierra RJ, Trousdale RT, Ganz R, Leunig M. Hip disease in the young, active patient: evaluation and nonarthroplasty surgical options. J Am Acad Orthop Surg. 2008 Dec;16(12):689-703.

(60.) Nunley RM, Prather H, Hunt D, et al. Clinical presentation of symptomatic acetabular dysplasia in skeletally mature patients. J Bone Joint Surg Am. 2011 May;93 Suppl 2:17-21.

(61.) Sabharwal S, Kumar A. Methods for assessing leg length discrepancy. Clin Orthop Relat Res. 2008 Dec;466(12):2910-22.

(62.) Sankar WN, Laird CT, Baldwin KD. Hip range of motion in children: what is the norm? J Pediatr Orthop. 2012 Jun;32(4):399-405.

(63.) Ganz R, Parvizi J, Beck M, et al. Femoroacetabular impingement: a cause for osteoarthritis of the hip. Clin Orthop Relat Res. 2003 Dec;(417):112-20.

(64.) Clohisy JC, Keeney JA, Schoenecker PL. Preliminary assessment and treatment guidelines for hip disorders in young adults. Clin Orthop Relat Res. 2005 Dec;441:168-79.

(65.) Hananouchi T, Yasui Y, Yamamoto K, et al. Anterior impingement test for labral lesions has high positive predictive value. Clin Orthop Relat Res. 2012 Dec;470(12):3524-9.

(66.) Clohisy JC, Knaus ER, Hunt DM, et al. Clinical presentation of patients with symptomatic anterior hip impingement. Clin Orthop Relat Res. 2009 Mar;467(3):638-44.

(67.) Eijer H, Myers SR, Ganz R. Anterior femoroacetabular impingement after femoral neck fractures. J Orthop Trauma. 2001 Sep-Oct;15(7):475-81.

(68.) Lequesne M, de S. [False profile of the pelvis. A new radiographic incidence for the study of the hip. Its use in dysplasias and different coxopathies]. Rev Rhum Mal Osteoartic. 1961 Dec;28:643-52.

(69.) Klaue K, Wallin A, Ganz R. CT evaluation of coverage and congruency of the hip prior to osteotomy. Clin Orthop Relat Res. 1988 Jul;(232):15-25.

(70.) Tonnis D, Heinecke A, Nienhaus R, Thiele J. [Predetermination of arthrosis, pain and limitation of movement in congenital hip dysplasia (author's transl)]. Z Orthop Ihre Grenzgeb. 1979 Oct;117(5):808-15.

(71.) Crowe JF, Mani VJ, Ranawat CS. Total hip replacement in congenital dislocation and dysplasia of the hip. J Bone Joint Surg Am. 1979 Jan;61(1):15-23.

(72.) Byrd JW, Jones KS. Hip arthroscopy in the presence of dysplasia. Arthroscopy. 2003 Dec;19(10):1055-60.

(73.) Parvizi J, Bican O, Bender B, et al. Arthroscopy for labral tears in patients with developmental dysplasia of the hip: a cautionary note. J Arthroplasty. 2009 Sep;24(6 Suppl):110-3.

(74.) Dorrell JH, Catterall A. The torn acetabular labrum. J Bone Joint Surg Br. 1986 May;68(3):400-3.

(75.) Yamamoto Y, Ide T, Nakamura M, et al. Arthroscopic partial limbectomy in hip joints with acetabular hypoplasia. Arthroscopy. 2005 May;21(5):586-91.

(76.) Kain MS, Novais EN, Vallim C, et al. Periacetabular osteotomy after failed hip arthroscopy for labral tears in patients with acetabular dysplasia. J Bone Joint Surg Am. 2011 May;93 Suppl 2:57-61.

(77.) Fujii M, Nakashima Y, Noguchi Y, et al. Effect of intraarticular lesions on the outcome of periacetabular osteotomy in patients with symptomatic hip dysplasia. J Bone Joint Surg Br. 2011 Nov;93(11):1449-56.

(78.) Kim KI, Cho YJ, Ramteke AA, Yoo MC. Peri-acetabular rotational osteotomy with concomitant hip arthroscopy for treatment of hip dysplasia. J Bone Joint Surg Br. 2011 Jun;93(6):732-7.

(79.) Trumble SJ, Mayo KA, Mast JW. The periacetabular osteotomy. Minimum 2 year followup in more than 100 hips. Clin Orthop Relat Res. 1999 Jun;(363):54-63.

(80.) Siebenrock KA, Scholl E, Lottenbach M, Ganz R. Bernese periacetabular osteotomy. Clin Orthop Relat Res. 1999 Jun;(363):9-20.

(81.) Ganz R, Klaue K, Vinh TS, Mast JW. A new periacetabular osteotomy for the treatment of hip dysplasias. Technique and preliminary results. Clin Orthop Relat Res. 1988 Jul;(232):26-36.

(82.) Millis MB, Kim YJ. Rationale of osteotomy and related procedures for hip preservation: a review. Clin Orthop Relat Res. 2002 Dec;(405):108-21.

(83.) Turgeon TR, Phillips W, Kantor SR, Santore RF. The role of acetabular and femoral osteotomies in reconstructive surgery of the hip: 2005 and beyond. Clin Orthop Relat Res. 2005 Dec;441:188-99.

(84.) Salter R. Innominate osteotomy in the treatment of congenital hip dislocation and subluxation of the hip. J Bone Joint Surg Br. 1961;43:518-39.

(85.) Wagner H. [Pelvic osteotomy of post-traumatic necrosis of the femoral head (author's transl)]. Unfallheilkunde. 1978 Mar;81(3):188-94.

(86.) Ninomiya S, Tagawa H. Rotational acetabular osteotomy for the dysplastic hip. J Bone Joint Surg Am. 1984 Mar;66(3):430-6.

(87.) Tonnis D, Behrens K, Tscharani F. A modified technique of the triple pelvic osteotomy: early results. J Pediatr Orthop. 1981;1(3):241-9.

(88.) Steel HH. Triple osteotomy of the innominate bone. J Bone Joint Surg Am. 1973 Mar;55(2):343-50.

(89.) Matta JM, Stover MD, Siebenrock K. Periacetabular osteotomy through the Smith-Petersen approach. Clin Orthop Relat Res. 1999 Jun;(363):21-32.

(90.) Clohisy JC, Barrett SE, Gordon JE, et al. Periacetabular osteotomy for the treatment of severe acetabular dysplasia. J Bone Joint Surg Am. 2005 Feb;87(2):254-9.

(91.) Sucato DJ. Treatment of late dysplasia with Ganz osteotomy. Orthop Clin North Am. 2006 Apr;37(2):161-71, vi.

(92.) Leunig M, Siebenrock KA, Ganz R. Rationale of periacetabular osteotomy and background work. Instr Course Lect. 2001;50:229-38.

(93.) Guevara CJ, Pietrobon R, Carothers JT, et al. Comprehensive morphologic evaluation of the hip in patients with symptomatic labral tear. Clin Orthop Relat Res. 2006 Dec;453:277-85.

(94.) Trousdale RT, Ekkernkamp A, Ganz R, Wallrichs SL. Periacetabular and intertrochanteric osteotomy for the treatment of osteoarthrosis in dysplastic hips. J Bone Joint Surg Am. 1995 Jan;77(1):73-85.

(95.) Crockarell J Jr, Trousdale RT, Cabanela ME, Berry DJ. Early experience and results with the periacetabular osteotomy. The Mayo Clinic experience. Clin Orthop Relat Res. 1999 Jun;(363):45-53.

(96.) Mayo KA, Tumble SJ, Mast JW. Results of periacetabular osteotomy in patients with previous surgery for hip dysplasia. Clin Orthop Relat Res. 1999 Jun;(363):73-80.

(97.) Steppacher SD, Tannast M, Ganz R, Siebenrock KA. Mean 20-year followup of Bernese periacetabular osteotomy. Clin Orthop Relat Res. 2008 Jul;466(7):1633-44.

(98.) Hussell JG, Rodriguez JA, Ganz R. Technical complications of the Bernese periacetabular osteotomy. Clin Orthop Relat Res. 1999 Jun;(363):81-92.

(99.) Staheli LT, Chew DE. Slotted acetabular augmentation in childhood and adolescence. J Pediatr Orthop. 1992 Sep-Oct;12(5):569-80.

(100.) Chiari K. Medial displacement osteotomy of the pelvis. Clin Orthop Relat Res. 1974 Jan-Feb;(98):55-71.

(101.) Ito H, Tanino H, Yamanaka Y, et al. The Chiari pelvic osteotomy for patients with dysplastic hips and poor joint congruency: long-term follow-up. J Bone Joint Surg Br. 2011 Jun;93(6):726-31.

(102.) Kotz R, Chiari C, Hofstaetter JG, et al. Long-term experience with Chiari's osteotomy. Clin Orthop Relat Res. 2009 Sep;467(9):2215-20.

(103.) Iwase T, Hasegawa Y, Kawamoto K, et al. Twenty years' followup of intertrochanteric osteotomy for treatment of the dysplastic hip. Clin Orthop Relat Res. 1996 Oct;(331):245-55.

(104.) Sponseller PD, McBeath AA, Perpich M. Hip arthrodesis in young patients. A long-term follow-up study. J Bone Joint Surg Am. 1984 Jul;66(6):853-9.

(105.) Callaghan JJ, Brand RA, Pedersen DR. Hip arthrodesis. A long-term follow-up. J Bone Joint Surg Am. 1985 Dec;67(9):1328-35.

(106.) Hauge MF. The knee in patients with hip joint ankylosis. Clinical survey and bio-mechanical aspects. Acta Orthop Scand. 1973;44(4):485-95.

(107.) Kirkos JM, Papavasiliou KA, Kyrkos MJ, et al. The long-term effects of hip fusion on the adjacent joints. Acta Orthop Belg. 2008 Dec;74(6):779-87.

(108.) Gore DR, Murray MP, Sepic SB, Gardner GM. Walking patterns of men with unilateral surgical hip fusion. J Bone Joint Surg Am. 1975 Sep;57(6):759-65.

(109.) Lindahl O. Determination of hip adduction, especially in arthrodesis. Acta Orthop Scand. 1965;36(3):280-93.

(110.) Beaule PE, Matta JM, Mast JW. Hip arthrodesis: current indications and techniques. J Am Acad Orthop Surg. 2002 Jul-Aug;10(4):249-58.

(111.) Milch H. The "Pelvic Support" osteotomy. J Bone Joint Surg Am. 1941;23(3):581-95.

(112.) Mahran MA, ElGebeily MA, Ghaly NAM, et al. Pelvic support osteotomy by Ilizarov's concept: is it a valuable option in managing neglected hip problems in adolescents and young adults? Strategies Traum Limb Reconstr. 2011 Apr;6(1):13-20.

(113.) Aksoy MC, Musdal Y. Subtrochanteric valgus-extension osteotomy for neglected congenital dislocation of the hip in young adults. Acta Orthop Belg. 2000 Apr;66(2):181-6.

(114.) Inan M, Alkan A, Harma A, Ertem K. Evaluation of the gluteus medius muscle after a pelvic support osteotomy to treat congenital dislocation of the hip. J Bone Joint Surg Am. 2005 Oct;87(10):2246-52.

(115.) Polkowski GG, Callaghan JJ, Mont MA, Clohisy JC. Total hip arthroplasty in the very young patient. J Am Acad Orthop Surg. 2012 Aug;20(8):487-97.

(116.) Kung PL, Ries MD. Effect of femoral head size and abductors on dislocation after revision THA. Clin Orthop Relat Res. 2007 Dec;465:170-4.

(117.) Lee BP, Cabanela ME, Wallrichs SL, Ilstrup DM. Bonegraft augmentation for acetabular deficiencies in total hip arthroplasty. Results of long-term follow-up evaluation. J Arthroplasty. 1997 Aug;12(5):503-10.

(118.) Rodriguez JA, Huk OL, Pellicci PM, Wilson PD Jr. Autogenous bone grafts from the femoral head for the treatment of acetabular deficiency in primary total hip arthroplasty with cement. Long-term results. J Bone Joint Surg Am. 1995 Aug;77(8):1227-33.

(119.) Mulroy RD Jr, Harris WH. Failure of acetabular autogenous grafts in total hip arthroplasty. Increasing incidence: a follow-up note. J Bone Joint Surg Am. 1990 Dec;72(10):1536-40.

(120.) Russotti GM, Harris WH. Proximal placement of the acetabular component in total hip arthroplasty. A long-term follow-up study. J Bone Joint Surg Am. 1991 Apr;73(4):587-92.

(121.) Schutzer SF, Harris WH. High placement of porous-coated acetabular components in complex total hip arthroplasty. J Arthroplasty. 1994 Aug;9(4):359-67.

(122.) Dorr LD, Tawakkol S, Moorthy M. Medial protrusio technique for placement of a porous-coated, hemispherical acetabular component without cement in a total hip arthroplasty in patients who have acetabular dysplasia. J Bone Joint Surg Am. 1999 Jan;81(1):83-92.

(123.) Hartofilakidis G, Stamos K, Karachalios T, et al. Congenital hip disease in adults. Classification of acetabular deficiencies and operative treatment with acetabuloplasty combined with total hip arthroplasty. J Bone Joint Surg Am. 1996 May;78(5):683-92.

(124.) Chareancholvanich K, Becker DA, Gustilo RB. Treatment of congenital dislocated hip by arthroplasty with femoral shortening. Clin Orthop Relat Res. 1999 Mar;(360):127-35.

(125.) Reikeraas O, Lereim P, Gabor I, et al. Femoral shortening in total arthroplasty for completely dislocated hips: 3-7 year results in 25 cases. Acta Orthop Scand. 1996 Feb;67(1):33-6.

(126.) Yasgur DJ, Stuchin SA, Adler EM, DiCesare PE. Subtrochan teric femoral shortening osteotomy in total hip arthroplasty for high-riding developmental dislocation of the hip. J Arthroplasty. 1997 Dec;12(8):880-8.

(127.) Restrepo C, Lettich T, Roberts N, et al. Uncemented total hip arthroplasty in patients less than twenty-years. Acta Orthop Belg. 2008 Oct;74(5):615-22.

(128.) Clohisy JC, Oryhon JM, Seyler TM, et al. Function and fixation of total hip arthroplasty in patients 25 years of age or younger. Clin Orthop Relat Res. 2010 Dec;468(12):3207-13.

(129.) Wangen H, Lereim P, Holm I, et al. Hip arthroplasty in patients younger than 30 years: excellent ten to 16-year follow-up results with a HA-coated stem. Int Orthop. 2008 Apr;32(2):203-8.

(130.) Numair J, Joshi AB, Murphy JC, et al. Total hip arthroplasty for congenital dysplasia or dislocation of the hip. Survivorship analysis and long-term results. J Bone Joint Surg Am. 1997 Sep;79(9):1352-60.

(131.) MacKenzie JR, Kelley SS, Johnston RC. Total hip replacement for coxarthrosis secondary to congenital dysplasia and dislocation of the hip. Long-term results. J Bone Joint Surg Am. 1996 Jan;78(1):55-61.

(132.) Lichtblau S. [Early recognition of congenital dislocation and congenital subluxation of the hip. An evaluation of Shenton's line]. Clin Orthop Relat Res. 1966 Sep-Oct;48:181-9.

(133.) Rhee PC, Woodcock JA, Clohisy JC, et al. The Shenton line in the diagnosis of acetabular dysplasia in the skeletally mature patient. J Bone Joint Surg Am. 2011 May;93 Suppl 2:35-9.

(134.) Reynolds D, Lucas J, Klaue K. Retroversion of the acetabulum. A cause of hip pain. J Bone Joint Surg Br. 1999 Mar;81(2):281-8.

(135.) Kalberer F, Sierra RJ, Madan SS, et al. Ischial spine projection into the pelvis : a new sign for acetabular retroversion. Clin Orthop Relat Res. 2008 Mar;466(3):677-83.

(136.) Tonnis D, Brunken D. [Differentiation of normal and pathological acetabular roof angle in the diagnosis of hip dysplasia. Evaluation of 2294 acetabular roof angles of hip joints in children]. Arch Orthop Unfallchir. 1968;64(3):197-228.

(137.) Sharp IK. Acetabular dysplasia: the acetabular angle. J Bone Joint Surg Br. 1961;43(2):268-72.

Rachel Y Goldstein, M.D., M.P.H., is a Juvenile Hip Preservation Fellow at Boston Children's Hospital, Boston, Massachusetts. Ian David Kaye, M.D., James Slover, M.D., and David Feldman, M.D., are in the Department of Orthopaedic Surgery, NYU Langone Medical Center, Hospital for Joint Diseases, New York, New York. Correspondence: Rachel Y Goldstein, M.D., M.P.H., Boston Children's Hospital, 300 Longwood Avenue, Hunnewell 221, Boston, Massachusetts 02115; rgoldstein@chla.usc.edu.

Goldstein RY, Kay ID, Slover J, Feldman D. Hip dysplasia in the skeletally mature patient. Bull Hosp Jt Dis. 2014;72(1):28-42.
Table 1 Radiographic Findings in the Evaluation of Hip Dysplasia

Radiographic
Finding          Description               Implication

On AP Pelvis

Shenton's Line   Projected arc from the    A break in the line (arc)
(132,133)        inferior border of the    reflects superior femoral
                 femoral neck to the       head subluxation indicative
                 superior border of the    of acetabular dysplasia
                 obturator foramen

Pistol-Grip      Femoral head extends      Represents an anterior
Deformity (55)   laterally in a convex     deformity and hip dysplasia
                 shape to the base of
                 the neck

Protrusio        Femoral head overlaps
                 the ilioischial line
                 medially

Profunda         Floor of the fossa
                 acetabuli touches the
                 ilioischial line

Crossover        The contours of           Acetabular retroversion
Sign (134)       anterior and posterior
                 wall cross medial to
                 the superolateral
                 aspect of acetabulum

Projection       Projection of ischial     Increased retroversion
of Ischial       spine
Spine (135)

Lateral          Angle between             Assesses the superior and
Center Edge      horizontal line through   lateral coverage of the
Angle (56)       center of both femoral    femoral head by the bony
                 heads and a line from     acetabulum
                 center of femoral head
                 to most superolateral
                 point of acetabulum

Tonnis           Angle between             Evaluates orientation of
Angle (136)      horizontal line through   acetabular roof or
                 both femoral heads and    inclination of the sourcil
                 a line from the most
                 medial point of the
                 weightbearing
                 acetabulum to the most
                 lateral point of the
                 acetabulum

Acetabular       Angle between             Measures the acetabular
Angle of         horizontal line through   inclination or opening
Sharp (137)      both inferior teardrop
                 and a line from the
                 inferior aspect of the
                 teardrop to the
                 superolateral aspect of
                 the acetabulum

Femoral Head     Distance between a line   Measures the percentage of
Coverage         through most medial       the femoral head covered by
                 aspect of the joint       the bony acetabulum
                 space and align through
                 the lateral aspect of
                 the acetabulum, divided
                 by the distance between
                 a line through the most
                 medial aspect of the
                 joint space and a line
                 through the most
                 lateral aspect of the
                 head

Neck Shaft       Angle between the axis    Evaluates the angle of the
Angle            of the femoral shaft      femoral neck
                 and the axis of the
                 neck passing through
                 the femoral head center

On False Profile View

Vertical         Angle between a           Evaluates the anterior and
Center           vertical line through     superior coverage of the
Anterior         the center of the         femoral head
Angle (68)       femoral head and an
                 oblique line running
                 from the center of the
                 head to the most
                 anterior point of the
                 acetabulum

Computed Tomography

Anterior         Angle between a line      Describes the relationship
Acetabular       formed through center     between the femoral head and
Sector Angle     of femoral heads and an   the acetabulum. These values
(AASA)/          oblique line from the     are decreased in acetabular
Posterior        center of the head to     dysplasia
Acetabular       the most anterior
Sector Angle     portion of the
(PASA)           acetabulum to determine
                 the AASA and to the
                 most posterior portion
                 of the acetabulum to
                 determine the PASA

Femoral Neck     Angle between the         Evaluates the version of the
Version          femoral neck and the      femur
                 posterior aspect of
                 femoral condyles

Table 2 Tonnis Classification of Hip Dysplasia

Grade   Description

0       No arthritic changes

1       Sclerosis, mild joint space loss, minimal
        osteophyte formation

2       Small cystic changes with moderate joint space loss

3       Large cysts and moderate to complete joint space
        loss

Table 3 Crowe Classification of Hip Dysplasia

Type   Description

I      subluxation < 50% of vertical diameter of femoral head

II     subluxation of 50% to 75% of vertical diameter of femoral head

III    subluxation of 75% to 100% of vertical diameter of femoral head

IV     proximal migration of > 100% of vertical diameter of femoral
       head
COPYRIGHT 2014 J. Michael Ryan Publishing Co.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2014 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Goldstein, Rachel Y.; Kaye, Ian David; Slover, James; Feldman, David
Publication:Bulletin of the NYU Hospital for Joint Diseases
Article Type:Report
Date:Jan 1, 2014
Words:10409
Previous Article:Legg-Calve-Perthes disease: an overview with recent literature.
Next Article:Lower extremity nerve trauma.
Topics:

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters