Fractures of the hand and carpal navicular bone in athletes.

Phalanges 

Articular surface fractures

Most articular surface fractures require evaluation by an orthopaedist or a hand surgeon. Many fractures are nondisplaced and can be managed with closed techniques, but a small subset are at risk for late displacement, and should be carefully followed with serial radiographs. Displaced fractures of the articular surface that are not associated with gross limb deformity often require open reduction, and should be evaluated by a surgeon within 3 to 5 days. Those associated with deformity of the digit should be referred emergently for reduction and fixation (Fig. 1).

Condylar fractures

These fractures are among the most challenging to treat operatively. (1) The attachments of the collateral ligaments and nearby tendons frequently cause late displacement of seemingly innocuous fractures. The extension into the joint results in hematoma formation, articular adhesions, and late stiffness. (2) This is especially problematic in the proximal inter-phalangeal joint, which has a tendency to grow stiff in flexion and is resistant to late capsular release.

Joint depression

Impacted fractures of the articular surface usually require operative treatment and should be promptly referred. They can be difficult to visualize (Fig. 2). Well-positioned radiographs are essential. Computed tomography is often used for surgical decision making, but should be ordered by the treating surgeon to ensure correct views are obtained. Some fractures are so comminuted that a temporary period of distraction followed by early motion is used to gain a fibrous articulation. (3) This can have surprisingly good function after healing.

Extraarticular fractures

Fractures of the shaft of the phalanx can be caused by rotation, bending, direct blows, indirect forces transmitted through sporting equipment, or a combination of these. (2) The degree of initial displacement and the risk of late shortening, angulation, or rotation is directly related to the extent of soft tissue damage sustained at the moment of initial injury. Nondisplaced fractures can often be managed with buddy taping. Close follow up with serial radiographs is needed for the early period after injury. This usually consists of films at 3 to 5 days, one week, and two weeks after injury. Injuries which are stable through this phase are unlikely to displace later. Displaced fractures will usually angulate in an apex volar direction due to attachments of the interossei muscles. (2) Phalangeal fractures in general are quite slow to demonstrate evidence of union on radiographs. The absence of local fracture site tenderness or pain with range of motion is the best guide to assessing healing, and is usually evident within three to four weeks after injury in adults.

Marginal fractures of the bases of phalanges are sometimes diagnosed as "avulsion fractures" and can be sentinels for more serious injuries. They are the result of a number of injury forces. Management is usually directed at treating the fracture in combination with the accompanying soft tissue (which is usually a bigger issue than the fracture itself). Examples include volar and dorsal fractures of the distal phalanx, volar plate injuries of the middle phalanx, and gamekeeper's thumb involving the thumb metacarpophalangeal joint. (4)

Metacarpals

Metacarpal fractures are quite common in sports due to the subcutaneous nature of the bones and the proximal-distal curve which makes them susceptible to bending loads. Injuries can be subdivided based on the location of the fracture.

Distal fractures. Distal fractures involving the metacarpal head are articular fractures by definition, and as such should receive urgent treatment. They can result from an axial load or through tension exerted by the collateral ligaments.

Metacarpal neck fractures. Metacarpal neck fractures are by far the most common fracture, especially in the fifth metacarpal. This "boxer's fracture" should be called a "fighter's fracture," given the fact that it often results from incorrect technique in swinging a fist. This results in an oblique force applied to the smallest, weakest metacarpal. Boxers are trained to strike with the radial side of the hand, using the strongest, most stable portion of the hand to hit their opponent. The metacarpal neck fracture usually displaces in an apex dorsal direction, resulting in a palmar position of the metacarpal head. A surprising degree of angulation can be tolerated as one moves from the index toward the small finger metacarpals, given the increasing mobility of the carpometacarpal joints in the lesser metacarpals. Patients should be counseled as to the loss of knuckle prominence and a sensation of fullness in the palm due to palmar displacement of the head. Nonoperative management consists of a period of splinting followed by buddy taping and early motion, with clinical healing usually occurring in four to six weeks. Nonunion is rare in these, and indeed, all metacarpal fractures.

[FIGURE 1 OMITTED]

Fractures of the shaft of the metacarpals are common as well. Their propensity for displacement is directly related to the extent of periosteal and surrounding muscle damage sustained at the moment of injury. Isolated fractures of the middle and ring finger are less likely to shorten after injury. This is due to the suspension of the distal fragment by the transverse metacarpal ligaments attached to the adjacent, uninjured bones on either side of the fractured metacarpal. The index and small finger do not have this support on both sides, resulting in the likelihood of shortening.

[FIGURE 2 OMITTED]

A greater concern than loss of length, however, is rotational deformity. (1) This can sometimes be difficult to assess on radiographs, and should be checked carefully on clinical examination. A small degree of rotation present at a proximal metacarpal shaft fracture can create a substantial degree of rotational deformity at the fingertip. This is best checked by having the patient close the hand with the pads of the digits lying on the palm (not a complete fist). Although swollen and painful immediately after a fracture, most patients can accomplish this maneuver with gentle coaxing. The hand should be compared with the uninjured side because each patient has a unique finger position in flexion, especially for the small and index metacarpals. Checking a hand encased in splint can be done by checking the plane of the fingernails and comparing this to the opposite side.

Stable shaft fractures can be treated with splinting or casting in the safe position for four weeks, followed by buddy-taped range of motion. (4) Return to sports is highly individualized and should be judged by the following criteria: absence of local signs such as fracture site tenderness; early healing on radiographs; range of motion recovery; sport specific needs for the hand; and whether any protection during sport can be applied or tolerated by the patient.

An offensive tackle with a nondisplaced metacarpal fracture may be able to return to contact within five days after injury if a suitably padded splint is applied before the game, with postgame icing and work on gentle range of motion. A fencer with a displaced fracture of the index metacarpal in the dominant hand requiring closed or open reduction may not tolerate noncompetitive practice for six weeks, and return to competition may take eight to ten weeks or longer.

Fractures of the base of the metacarpal. Fractures involving the base of the metacarpal should be scrutinized carefully to rule out any involvement of the adjacent carpometacarpal joint (Fig. 3). This is most common in the ring and small metacarpals, and usually consists of a dorsal dislocation of the metacarpal bases on the hamate. These dislocations are easily reduced, but have a marked tendency to resubluxate. Most are treated with percutaneous pinning to prevent late displacement. Rotation should also be checked carefully.

Thumb metacarpal base. Fractures involving the thumb metacarpal shaft and base (distal to the joint surface) are treated in a thumb spica cast after reduction. Significant deformity can be tolerated due to the intrinsic mobility of the trapeziometacarpal joint. The fracture tends to collapse in an ulnar direction, but this does not seem to interfere greatly with function.

Articular fractures of the thumb metacarpal base comprise an important subset of hand injuries. They result from an axial load applied to the thumb. The pull of the adductor pollicis causes the distal portion of the thumb to displace toward the palm, while the base of the joint displaces in the opposite direction due to the pull of the abductor pollicis longus (Fig. 4). This abnormal posture of the thumb exacerbates the diastasis of the joint surface. Although some controversy exists regarding optimal treatment type, most authors agree that surgical referral with some form of operative stabilization is necessary to protect these unstable fractures from displacement. (1,2)

[FIGURE 3 OMITTED]

Scaphoid. The scaphoid is the most commonly fractured carpal bone. These fractures usually result from forced dorsiflexion and axial load. The scaphoid is unique in that it serves as a link or strut bone in the wrist. It is very instrumental in maintaining normal carpal mechanics. The blood supply to the scaphoid primarily flows distal to proximal. Its disruption can lead to nonunion. The blood supply is also significant in that these fractures have a protracted time to union, ranging from nine weeks for waist fractures up to 20 weeks for proximal pole fractures (Fig. 5).

The unique "kidney bean" shape of the scaphoid can complicate the visualization of fracture lines. In addition, some fractures may not be visible on plain radiographs until some fracture site resorption is present. A history of a forced dorsiflexion injury and findings of tenderness and swelling in the anatomic snuffbox should alert the examiner to the possibility of an occult scaphoid injury. (1) These patients should be immobilized in a splint or cast which includes the thumb. New radiographs should be obtained 10 to 14 days later. This delay in diagnosis is usually unacceptable to athletes, coaches, and family members. Bone scanning can be used to identify a fracture in the acute postinjury period; however, magnetic resonance imaging is the more sensitive study. It is usually positive within 24 hours after injury. It also allows for the delineation of fracture anatomy and can assist in surgical planning. A limited study when available is comparable in cost to a bone scan.

[FIGURE 4 OMITTED]

[FIGURE 5 OMITTED]

Nondisplaced fractures are normally treated with cast immobilization. Players can resume play if their sport and position permit a playing cast. Rates of union (even among contact athletes) are comparable to nonathletes wearing a cast. (5) Above-elbow casting is usually used for the first six weeks, followed by application of a below-elbow cast until union is achieved. The use of internal fixation to stabilize nondisplaced fractures in order to allow early return to play has been described by multiple authors. (5,6) This permits rapid return of wrist motion and obviates the need for a playing cast in a finesse sport or position. These screws can be inserted through very limited incisions (less than one centimeter) with minimal morbidity to the athlete.

Displaced fractures are treated surgically, and should be splinted after identification and referred to a hand surgeon within 3 to 5 days. Radiographs should be carefully reviewed to rule out a complex fracture-dislocation of the wrist with subluxation of the lunate. This is an emergent condition and requires immediate reduction. Return to play is dependent on the stability noted at the time of surgery and individual sport requirements.

The quality of a university is measured more by the kind of student it
Turns out than the kind it takes in.
--Robert J. Kibbee

Accepted May 21, 2004.

References

1. Trumble TE. Principles of Hand Surgery and Therapy. Philadelphia, W.B. Saunders, 2000.

2. Lee SG, Jupiter J. Phalangeal and metacarpal fractures of the hand. Hand Clinics 2000;16:323-332.

3. Glickel SZ, Barron OA. Proximal interphalangeal joint fracture dislocations. Hand Clinics 2000;16:333-344.

4. Melone CP, Beldner S, Basuk RS. Thumb collateral ligament injuries. Hand Clinics 2000;16:345-357.

5. Rettig AC, Weidenbener EJ, Gloyeske R. Alternative management of midthird scaphoid fractures in the athlete. Am J Sports Med 1994;22:711-714.

6. Rettig AC, Kollias SC. Internal fixation of acute stable scaphoid fractures in the athlete. Am J Sports Med 1996;24:182-186.

John J. Walsh IV, MD

From the Section of Hand Surgery, Department of Orthopaedics, the University of South Carolina School of Medicine, Columbia, SC.

Reprint requests to John J. Walsh IV, MD, University of South Carolina School of Medicine, Two Medical Park, Suite 404, Columbia, SC 29203.