Use of a Classification System to Guide Nonsurgical Management of a Patient With Chronic Low Back Pain.

Despite being one of the most commonly treated disorders in outpatient physical therapy practice,[1] the management of low back pain (LBP) continues to be a challenge. We believe that 2 issues, in particular, contribute to this challenge. The first issue relates to the lack of an accepted classification system for LBP that is feasible to use and that is validated through research. The second issue relates to the conceptual distinction between physical impairment and functional limitation, and the degree to which each is addressed in the treatment of patients with low back-related disorders.

The need to classify patients into homogenous subgroups to better facilitate the management of LBP has received much attention in recent literature.[2-15] This need is reflected by the number of classification systems that have been proposed within the past 2 decades.[2-12] Riddle[13] provided a comprehensive review of the classification systems deemed most relevant to physical therapists, along with a discussion of issues related to LBP classification. There is no consensus regarding the most appropriate classification scheme to guide the rehabilitation of patients with LBP.[14] In the view of many authors, the ability to differentiate among various subgroups of patients with LBP would enhance both the clinical management and the scientific study of LBP.[14,15]

Measures of physical impairment such as range of motion, muscle force, and endurance are routinely assessed by physical therapists, with the goal of using the data obtained with these measures to help direct the management of patients with LBP.[1,16] However, as noted by Jette,[17] several major conceptual models indicate that physical impairments reflect only one aspect of the disablement process. Several authors[17-19] have suggested that rehabilitation professionals must also consider functional limitations and disability. The terms "functional limitation" and "disability" will be considered together in this report and refer to an inability to perform the basic tasks of daily life and to fulfill one's social and occupational roles.[18] In a recent survey of patients with chronic LBP (chronic LBP in this study was defined as 8 or more episodes of recurrent LBP spaced at least 90 days apart within a 3-year period), difficulty performing everyday activities was the most frequently cited reason for seeking medical care.[20] However, in a national sample of over 2,300 outpatient physical therapy records, Jette et al[1] found that therapists cited independent function as a treatment goal for only 10.6% of all patients treated for LBP. Functional training was included in only 5.6% of the rehabilitation programs. A more recent study of physical therapy for LBP similarly revealed that the number of goals relating to range of motion (65%) and pain reduction (53%) outnumbered those relating to the facilitation of functional activity (20%).[21] Together, these studies suggest that physical therapists may tend to address physical impairments more readily than functional limitations in the treatment of patients with low back-related disorders.

Delitto[19] observed that clinicians may be more inclined to document measures of physical impairment compared with limitations of function based on the underlying assumption that correction of impairments will result in improved treatment outcomes. However, the link between physical impairment and decline in function in people with LBP remains unclear. Several research groups have failed to find an association between various impairment measures and subsequent development of LBP.[22-28] The absence of an established relationship between physical impairment and function in individuals with LBP suggests that limitations of function should be addressed directly in any therapeutic program that seeks to improve functional outcomes.

The purpose of this case report is 2-fold. First, we will describe the use of a classification system in the evaluation of a patient with chronic LBP. Second, we will demonstrate how this classification system was used to guide development of a treatment plan that included modification of symptom-producing motions and alignments of the lumbar spine during the performance of daily work, leisure, and self-care activities. In doing so, we hope to illustrate the potential benefits of using a classification approach to guide identification and treatment of the symptom-provoking movements and postures that are specific to each individual.

Conceptual Overview of LBP Classification Approach

The system of classification described in this report was designed in an effort to aid clinicians in identifying the primary movement problem toward which we believe physical therapy intervention should be directed. Therefore, each category of the classification system is named for the specific direction of spinal alignment or motion that is found to be consistently associated with an increase in LBP during testing. A summary of the signs and symptoms associated with each of the 5 categories proposed in this classification system is presented in Table 1.[12,29] The validity of data obtained with this classification system has not been demonstrated experimentally. The interrater reliability of data obtained for physical examination items used to classify patients according to this system has been reported previously (kappa [is greater than or equal to] .87 for 100% of items related to symptom production; kappa [is greater than or equal to] .42 for 72% of items related to alignment and movement signs).[12]

Table 1. Mechanical Low Back Pain Classification Categories, With Associated Signs and Symptoms[29]

Category        Associated Signs and Symptom Behavior

Flexion         Tendency for the lumbar spine to move in the
                direction of flexion with movements of the spine
                and extremities. Lumbar spine alignment tends to
                be flexed relative to neutral(a) with the
                assumption of postures (ie, standing, sitting,
                supine, side lying, prone, quadruped).

                Symptoms occur or increase with the lumbar spine
                positioned or moved into flexion.

                Symptoms disappear ar decrease with restriction(b)
                of lumbar flexion.

Extension       Signs and symptoms are similar to those described
                far flexion except that they occur with extension.

Rotation        Tendency for the lumbar spine to move in the
                direction of rotation with movements of the spine
                and extremities. Lumbar spine alignment tends to
                be rotated relative to neutral with the assumption
                of postures.

                Symptoms (often unilateral) occur or increase with
                the lumbar spine positioned or moved into
                rotation.

                Symptoms disappear or decrease with restriction of
                lumbar rotation.

Rotation with   Tendency for the lumbar spine to move in the
flexion         direction of rotation and flexion with movements
                of the spine and extremities. Lumbar spine
                alignment tends to be flexed and rotated relative
                to neutral with the assumption of postures.

                Symptoms (often unilateral) occur or increase with
                the lumbar spine positioned or moved into
                rotation and flexion.

                Symptoms disappear or decrease with restriction of
                lumbar rotation and flexion

Rotation with   Signs and symptoms are similar to those described
extension       for rotation with flexion except that they occur
                with rotation and extension.

(a) "Neutral" is defined as the position of the lumbar spine at which an inclinometer centered over each lumbar spinous process would result in a measure of 0 degrees, without rotation or side bending of any of the lumbar vertebrae.[12]

(b) Restriction of spinal motions and alignments is accomplished using verbal cues, active stabilization by the patient, and manual stabilization by the examiner.

An underlying assumption of this approach is that the daily repetition of similar movements and postures can result in movement of the lumbar spine in a specific direction, which then may contribute to the development, persistence, or recurrence of mechanical LBP.[12] We believe that the direction of spinal motion associated with an increase in low back-related symptoms reflects movement strategies and postures that are repeated by a given individual throughout each day. For example, an avid tennis player may be inclined to develop a symptom causing predisposition for motion of the lumbar spine into a direction of extension and rotation, whereas a cyclist may be more likely to develop symptoms associated with lumbar flexion and rotation. Presumably, individuals may develop habitual movements and postures in response to functional activity demands that may contribute to LBP and that may be identified and corrected through the evaluation of alignments and motions of the lumbar spine.

To classify a patient as being in 1 of the 5 categories listed in Table 1, we believe that the clinician should attempt to identify a consistent pattern of signs (ie, direction-specific motions and alignments of the lumbar spine) and symptoms (ie, reproduction of low back-related complaints, including numbness, tingling, or pain in the back or lower extremities) in response to items performed in several different test positions (eg, standing, sitting). Due to the anatomical relationship between the spine and extremities, motions of the spine that occur during limb movement are evaluated in addition to overt spinal motions that occur during movement of the torso (eg, forward bending). Confirmation that the symptom-provoking spinal motion or alignment has been correctly identified occurs by restricting that motion or alignment and noting whether there is a reduction of symptoms (see Appendix in the full-text version of this article on the Physical Therapy Web site at http://www.apta.org/pt_journal).

In this system of classification, the primary direction of symptom-provoking spinal motion or alignment identified in the examination as causing symptoms is referred to as the lumbar movement dysfunction. We believe that once a patient has been classified according to the primary movement dysfunction, treatment strategies designed to limit direction-specific motions or alignments that increase the patient's low back-related symptoms can be implemented. We consider identification and correction of the lumbar movement dysfunction during work, leisure, and self-care activities to be a priority due to the presumed frequency with which these movements and postures are repeated throughout each day. We also believe that impairments in muscle force and joint flexibility should be addressed relative to their possible contribution to the lumbar movement dysfunction.

Case Description

Patient

The subject of this case report was a 55-year-old woman referred for physical therapy with a medical diagnosis of degenerative disk disease and degenerative joint disease of the lumbar spine. The radiography report described findings of decreased intervertebral disk space extending from L2 to S1, as well as decreased joint space and sclerotic changes in the facet joints at L2-3 and L4-5. The patient reported a 40-year history of recurrent LBP, with multiple episodes each year, and symptoms that typically persisted less than a week before resolving spontaneously. Previous management for the patient's current episode of LBP included approximately 12 physical therapy sessions at an unrelated facility. The patient reported these sessions to be marginally effective in reducing her low back-related symptoms at the time of treatment, with an exacerbation of symptoms occurring within 2 weeks of her final visit to that facility.

The patient's self-reported medical history included bladder neck suspension surgery performed in 1991 for the treatment of urinary incontinence, along with a history of cigarette smoking and high blood pressure. Medications included calcium supplements, Wellbutrin(*) (prescribed as an antidepressive agent), Premarin([dagger]) (prescribed as a cholesterol-lowering agent), cyclobenzaprine (prescribed as a muscle relaxant), and ibuprofen. The patient reported taking the latter 2 medications infrequently for the relief of severe low back-related symptoms. The patient was self-employed as an insurance agent and worked approximately 40 hours per week from her home office. We were aware of no change in the patient's medications or employment during the course of treatment or during the 3-month follow-up period.

The symptoms for which the patient sought intervention began approximately 10 weeks prior to her first visit to our facility. Symptoms that persist for this duration are considered to be of a chronic nature by the Quebec Task Force for Spinal Disorders.[30] The patient reported that she had a constant ache across the central low back that fluctuated throughout the day. The average intensity of her symptoms was 6 on a verbal pain scale ranging from 0 to 10. The 11-point numeric rating scale of average pain intensity has been found to yield reliable measurements[31] and to be related to other measures of pain intensity when used by patients with LBP.[32] She was told that a rating of 0 should represent the absence of pain and a rating of 10 was the worst pain imaginable. The patient also noted an intermittent stabbing pain along her left posterior thigh and calf, which she said was exacerbated by twisting motions of the trunk. A tingling sensation was occasionally present in the left toes. The patient reported that the onset of her symptoms occurred after walking at a slow pace on a treadmill in her home for several minutes. The patient described herself as inactive, and she said that she had attempted to begin walking to help lose weight. She reported a gradual worsening of symptoms in the first few days after walking on her treadmill, with no notable improvement or decline of symptoms in subsequent weeks. She described having particular difficulty performing the following activities due to increased low back-related symptoms: brushing her teeth, rolling toward her left side, loading the dishwasher, getting into and out of her truck, and walking long distances, such as when grocery shopping.

The patient described in this case report was part of an ongoing clinical study of the effects of modifying symptom-producing movements and postures during a physical examination being conducted by the third author. The patient was recruited from 1 of 6 outpatient physical therapy clinics participating in a previous study by our group.[12] With the exception of a notably higher Oswestry Disability Questionnaire[33] score (43% versus 24%), this patient exhibited characteristics similar to the patient population described in a previous report on the interrater reliability of data obtained by examiners administering physical examination items used in the classification of mechanical LBP.[12]

Examination

To classify the patient's lumbar movement dysfunction according to the system described above, the first author conducted posture and movement testing with the patient in the following positions: standing, sitting, supine, side lying, prone, and quadruped. The first author had limited experience ([is less than] 6 months) with the proposed system of classification prior to receiving training, which was similar to that received by therapists participating in a previous study.[12] Briefly, training consisted of 5 individualized instruction sessions of 45 minutes to 1 hour duration with therapists having documented experience in the proposed classification system[12] and completion of a written examination on the content of a reference manual containing operational definitions of terms and standardized clinical examination procedures.

The patient's self-selected movement strategy or posture was assessed for signs of movement dysfunction during performance of each test item. Prior to each test, the patient assumed a reference position in which the intensity and location of the low back-related symptoms were assessed. For tests of alignment, the patient was asked to assume the test position for at least 10 seconds before noting any change in symptoms relative to symptoms in the reference position. For active movement tests, the patient was asked to indicate the point in the range of trunk or limb movement at which a change in symptoms occurred relative to symptoms in the reference position. The patient indicated whether the symptoms increased, decreased, or remained the same with each new position or movement, and descriptions of symptoms were noted. Any test that elicited an increase in the patient's symptoms was repeated, but was modified in an attempt to alleviate the symptoms. Modification of each test item involved restriction of the specific spinal motion or alignment that was observed during performance of the initial, symptom-provoking test. Restriction of symptom-producing spinal motions and alignments was accomplished using verbal cues, active stabilization by the patient, and manual stabilization by the examiner. Following each modified test item, the patient again was asked to indicate the status of her symptoms. Procedures used in the examination of motions and alignments of the lumbar spine are described in further detail in the Appendix (shown in the full-text version of this article on the Physical Therapy Web site at http://www.apta.org/ pt_journal). Findings from the examination of the patient are presented in Table 2.[12,30]

Table 2. Findings From Examination of Alignments and Movements of the Lumbar Spine(a)

                  Test Response With          Test Response With
                  Self-Selected Alignments    Modified Alignments
Test Item         and Movements(b)            and Movements

Standing          No change in status of
forward bending   symptoms

Return from       Large excursion into        No signs of spinal
forward bending   spinal extension prior      extension
                  to onset of hip extension
                  (eg, return to upright      Central LB sxs
                  position accomplished by    eliminated(c)
                  leading with back rather
                  than hips)

                  [up arrow](c) in
                  intensity of central
                  LB(d) sxs

Standing lumbar   Lumbar extension            No modified test
extension
                  [up arrow] in intensity
                  of central LB sxs

Side bending      Rotation of pelvis and      No signs of pelvic
                  lumbar spine in the         or lumbar rotation
                  horizontal plane when
                  side bending toward left    Central LB sxs
                                              eliminated
                  [up arrow] in intensity
                  of central LB sxs

Sitting           Preferred position with
                  lumbar spine aligned in
                  extension and lateral
                  side bend relative to
                  neutral(e)

                  [down arrow](c) in
                  intensity of central LB
                  sxs (relative to
                  weight-bearing position
                  in which lumbar spine was
                  similarly aligned in
                  extension)

Sitting with      No change in symptoms
lumbar spine
flexed

Sitting with      No change in symptoms
lumbar spine
extended

Sitting active    No change in symptoms
knee extension

Supine hips and   No change in symptoms
knees flexed

Supine passive    No change in symptoms
double knees to
chest

Supine hips and   No change in symptoms
knees extended

Supine active     Lumbar extension with       No signs of lumbar
single knee       initiation of right LE      extension or pelvic
to chest          movement CW pelvic          rotation
                  rotation with initiation
                  of right LE movement        Central LB sxs
                                              eliminated
                  [up arrow] in intensity
                  of central LB sxs with
                  initiation of right LE
                  movement

                  [down arrow] in intensity
                  of central LB sxs during
                  late phase of right LE
                  movement as knee moved
                  closer toward chest,
                  reducing amount of lumbar
                  extension

Supine active     No change in symptoms
hip abduction
and lateral
rotation

Side lying        Preferred position with
                  hips and knees flexed
                  >90 [degrees] and lumbar
                  spine aligned in flexion
                  relative to neutral

                  [down arrow] in intensity
                  of central LB sxs

Prone             Lumbar extension            No signs of lumbar
                                              extension
                  [up arrow] in intensity
                  of central LB sxs           [down arrow] in
                                              intensity of
                                              central LB sxs

Prone active      No change in status of
knee flexion      symptoms

Prone active      Lumbar extension and CCW    No signs of lumbar
hip rotation      pelvic rotation during      extension or pelvic
                  movement of left hip into   rotation
                  lateral rotation
                                              Left posterior
                  Change in location of       thigh sxs
                  sxs from central LB,        eliminated
                  to central LB and left
                  posterior thigh             No change in
                                              intensity of
                                              central LB sxs

Prone active      Lumbar extension and CCW    No signs of lumbar
hip extension     pelvic rotation during      extension or
                  left hip extension          pelvic rotation
                                              with modified
                  Lumbar extension and CW     test for left and
                  pelvic rotation during      right hip extension
                  right hip extension
                                              Left posterior
                  Change in location of       thigh and central
                  sxs from central LB in      LB sxs eliminated
                  prone, to central LB and    with modified test
                  left posterior thigh        for left and right
                  during extension of         hip extension
                  each hip

Quadruped         Preferred position with     No signs of lumbar
                  lumbar spine aligned in     extension or
                  extension and lateral       lateral side
                  side bend relative to       bending
                  neutral
                                              Central LB sxs
                  [up arrow] in intensity     eliminated
                  of central LB sxs

Quadruped         No change in symptoms
active arm lift

Quadruped         No change in symptoms
rocking
backward

Quadruped         No change in symptoms
rocking
backward in
full flexion

Quadruped         No change in symptoms
rocking forward

(a) Signs of direction-specific alignment or movement of the lumbar spine were recorded and modified only when associated with an increase in the patient's symptoms. Modification of each test item (third column) was accomplished with verbal cues, active stabilization by the patient, and manual stabilization by the examiner to specifically restrict the symptom-related alignments or motions (second column) listed for each item. A complete description of each test item is provided in the Appendix. Abbreviations: [up arrow] = increase, [down arrow] = decrease, LB=low back, sxs=symptoms, LE=lower extremity, CCW=counterclockwise (ie, forward rotation of the right hip with backward rotation of the left hip), CW=clockwise (backward rotation of the right hip with forward rotation of the left hip).

(b) "Self-selected alignments and movements" refers to alignments and movements of the lumbar spine that are observed when the patient initially assumes a test position (eg, sitting) or performs a test movement (eg, forward bending) using his or her preferred movement strategy with no further instruction from the examiner.

(c) An "increase" in symptoms is defined as pain or paresthesias that were either produced, increased in intensity, or moved distally from the lumbar spine with assumption of a test position or performance of a test movement. A "decrease" in symptoms is defined as pain or paresthesias that either diminished in intensity or moved proximally toward the lumbar spine with assumption of a test position or performance of a test movement. "Eliminated" is defined as the absence of symptoms that were present during assumption of a previous test position or performance of a previous test movement.

(d) "Central LB" refers to the region surrounding the spine extending from T12 to the gluteal fold.[29]

(e) "Neutral" is defined as that position of the lumbar spine at which an inclinometer centered over each lumbar spinous process would result in a measure of 0 degrees, without rotation or side bending of any of the lumbar vertebrae.[12]

Active control of the alignment of the lumbar spine was facilitated by verbally and/or manually cueing the patient to contract her abdominal muscles just prior to and throughout the attainment of each modified test position or movement. She had difficulty using her abdominal muscles and often held her breath, which we presumed was to compensate for a lack of muscular control. Successful attempts at using the abdominal muscles, as identified through palpation, frequently resulted in complaints of cramping and pain localized to the pelvic region. The patient indicated that she had been experiencing such symptoms regularly in the 8 years since her bladder neck suspension surgery. The intensity of these symptoms could be reduced or eliminated by instructing the patient to reduce the effort of abdominal muscle contraction.

The first author also examined muscle force and joint flexibility to determine which physical impairments might contribute to the observed tendency for direction-specific motions and alignments of the lumbar spine. Pretreatment and posttreatment impairment measurements are summarized in Table 3.[29,34-38] The patient displayed no signs of neurological deficit, as assessed by light touch sensation and manual muscle testing of L1-S1 myotomes.[39] The straight-leg-raising test[39] was negative for signs of neural tension. Results of testing for nonorganic signs of magnified illness behavior as described by Waddell et al[40] also were negative. Neurologic and Waddell tests were used to identify the presence of nerve impairment and to rule out magnified illness behavior. Results were not used in classification of the patient's primary movement dysfunction.

Table 3. Pretreatment and Posttreatment Physical Impairment Measurements(a)

                                  Pretreatment   Posttreatment

Lumbar spine excursion range of
motion (ROM) ([degrees])(b)
  Flexion                         30 [degrees]   80 [degrees]
  Extension                        8 [degrees]   45 [degrees]
  Side bend right                 34 [degrees]   31 [degrees]
  Side bend left                  32 [degrees]   24 [degrees]
Muscle length ([degrees]) as
indicated by ROM(c)
  Hamstrings (R/L)                 70/78          76/67
  Latissimus dorsi (R/L)          151/145        163/145
  Hip flexors (R/L)(d)            -30/-20          0/-10
Muscle force(e)
  Hip medial rotators (R/L)(c)    4+/4-          4+/4
  Tensor fascia lata (R/L)(c)      3/3+           3/3+
  Gluteus medius (R/L)(c)          3/4            3+/3+
  Lower abdominals(f)             NT              2

(a) Flexibility and force tests performed for all major lower-extremity muscle groups. Measurements listed only for those tests that revealed limitations. Twelve-week time interval between pretreatment and posttreatment measurements.

(b) Spinal range-of-motion measurements reflect excursion of the lumbar spine from a position of upright standing and were obtained using the 2-inclinometer method with landmarks over the L1 and S2 spinous processes. Intrarater reliability for 3 examiners measuring 15 patients with low back pain has been reported to range from r=.13 to r=.85.[34]

(c) Tests performed as described by Kendall et al.[35] R=right, L=left. The average intrarater reliability for 4 examiners performing upper- and lower-extremity goniometric measurements on 12 male subjects without impairments has been reported to be r=.85.[36]

(d) The average intraclass correlation coefficient for indexing intrarater reliability for 2 examiners performing a modified version of the hip flexor length test as described by Kendall et al[35] on 10 subjects without impairments has been reported to be .82.[37]

(e) Muscle force grades were assigned using a modified Medical Research Council (MRC) grading scale,[38] with grades ranging from 0 to 5. Weighted kappa values to index the intrarater reliability for 4 examiners performing testing of proximal lower-extremity muscle groups according to the MRC scale in 102 patients with Duchenne muscular dystrophy ranged between .71 and .93.[38] Substitution of hip flexors noted on testing of hip medial rotator, tensor fascia lata, and gluteus medius muscles at pretreatment assessment only. (Note: all substitutions were corrected prior to assigning a manual muscle test grade.)

(f) Lower abdominal muscle force test performed as described by Sahrmann.[29] NT=not able to test because of pain.

The examiner believed that substitution using the hip flexors occurred during manual muscle testing of several lower-extremity muscle groups (Tab. 3). Hip flexor substitution was thought to be present when the extremity being examined moved from the desired manual muscle test position into a position of increased hip flexion. Excessive use of the hip flexors also was observed throughout the examination as the patient moved in her accustomed manner. For example, the patient's self-selected strategy for moving from a sitting position to a supine position was first to assume a long-sitting position and then to lower her upper body toward the support surface using no upper extremity assistance. This method, which presumably required eccentric contraction of the hip flexor muscles, was associated with an increase in LBP. The patient also exhibited a habit that she referred to as "nervous legs," characterized by rapid bouncing movements of the lower extremities, apparently initiated at the hip. This habit was observed intermittently throughout the examination, most often when the patient was sitting or lying supine.

Classification and Intervention

Based on the signs and symptoms noted during the examination, we believed that the patient's primary movement dysfunction was lumbar rotation with extension (Tab. 4). We viewed decreased hip flexor length and excessive use of the hip flexor muscles during the performance of routine activities as impairments having the potential to contribute to rotation and extension of the lumbar spine with static postures and active movements of the spine and extremities. Our goal was to improve the patient's ability to perform functional activities, while minimizing the symptoms associated with rotation and extension of the lumbar spine.

Table 4. Test Items for Which Patient's Symptoms Were Decreased or Eliminated With Restriction of Spinal Alignment or Movement(a)

Flexion                Extension             Rotation

No lumbar flexion      Return from forward   Side bending (left)
associated with an       bending
increase in symptoms   Prone

Rotation With Flexion    Rotation With Extension

No lumbar flexion with   Supine active single knee to
rotation associated        chest (right)
with an increase in      Active hip lateral rotation (left)
symptoms                 Active hip extension (bilateral)
                         Quadruped

(a) Test items listed according to the specific direction of spinal alignment or movement that was restricted during performance of the modified test for each item (see Tab. 2). Classification is determined based on the category having the majority of test items in which symptoms are increased. Priority in determining the low pack pain classification category is given to those tests in which the examiner is able to decrease or eliminate symptoms by restricting the specific direction of spinal motion or alignment found to be associated with an increase in symptoms during the initial test.

During her initial visit, the patient was given instructions for activity modification based on the category to which she was assigned. The recommended strategies for activity modification are summarized in Table 5.[12] A feature common to each of these strategies was the specific discouragement of rotation and extension of the lumbar spine during daily activities. Along with addressing the activities that the patient identified as problematic, other tasks commonly associated with rotation and extension of the lumbar spine, such as reaching overhead or across the body, also were addressed (Tab. 5).

Table 5. Category-Specific Treatment Plan(a)

                          Functional Instruction(b)

Activity               Do:                    Do Not:

Forward bending/       Contract abdominals    Arch LB when
return from forward    to support spine in    returning to the
bending (eg,           neutral(d) or          upright position
brushing teeth,        slightly flexed
washing dishes)        alignment

                       Flex at hip joints
                       and maintain neutral
                       alignment of lumbar
                       spine while bending
                       forward

                       Extend at hip joints
                       and maintain neutral
                       alignment of lumbar
                       spine while
                       returning to the
                       upright position

Supine ?? sit          1. Bend knees by       Move directly from
transfers and             sliding 1 heel at   supine to
rolling                   a time toward       long-sitting by
                          body. Gently dig    flexing at hip
                          heel into support   joints
                          surface while
                          sliding leg.        Lift both legs
                          Contract            simultaneously from
                          abdominals to       support surface
                          support spine so
                          that LB maintains   Arch or twist LB
                          contact with        when moving legs
                          support surface
                          throughout leg      Use lumbar roll when
                          movement. Avoid     sitting
                          arching LB with
                          leg movement.

                       2. Roll onto side
                          moving the entire
                          body as a single
                          unit. Avoid
                          twisting. Use
                          arms to push to
                          upright sitting
                          as legs drop
                          over side of
                          support surface
                          at the same time.

                       Reverse the
                       technique to perform
                       sit ?? supine
                       transfers.

Vehicle transfers      Sit on edge of seat    Twist trunk while
                       facing door and        getting into and out
                       scoot as far back as   of vehicle
                       possible, then pivot
                       to face forward
                       while using arms to
                       help lift legs into
                       vehicle

Walking                Keep hips as level
                       as possible

                       Take smaller steps
                       and reduce amplitude
                       of arm swing to help
                       avoid excessive
                       twisting of pelvis

                       Take frequent short
                       breaks if walking
                       long distances

                       Move feet to turn
                       body rather than
                       twisting trunk

Overhead and           Contract abdominals    Arch LB when
cross-body reaching    to support spine in    reaching overhead
(eg, reaching for      neutral alignment
items located in       when moving arms       Twist LB when
overhead cabinets,                            reaching across body
reaching for items     Whenever possible,
not directly in        stand directly in
front of body,         front of an item
raising arms           before reaching
overhead to don/doff
shirt, raising arms
to wash or style
hair)

Sitting                Sit with LB either     Sit forward on edge
                       in neutral or          of chair or place a
                       slightly flexed        lumbar roll behind
                       alignment              LB

                       Use the chair back     Bounce legs
                       for support            repeatedly while
                                              sitting or let legs
                       Support feet while     dangle unsupported
                       sitting. Relax legs
                       and let chair
                       support the weight
                       of thighs.

                       Cross legs at ankles
                       rather than at
                       thighs to avoid
                       pelvic rotation

                       Take frequent breaks
                       by standing up or
                       performing a
                       "push-up" from chair
                       (ie, push down on
                       arm rests to lift
                       buttocks from chair
                       seat)

                             Exercise Instruction(c)

Activity               Initial:                Progression:

Forward bending/       Same as modified        Same as modified
return from forward    forward bending/        forward bending/
bending (eg,           return from forward     return from forward
brushing teeth,        bending (see            bending without use
washing dishes)        Appendix for patient    of arms to support
                       position and            weight of upper
                       instructions) (2)       both (3)

Supine ?? sit          Same as step 1 for      Same as step 1 for
transfers and          supine ?? sit           supine ?? sit
rolling                transfers               transfers

                       Perform with 2          Perform without
                       pillows placed under    pillows (3)
                       knee of stationary
                       limb to help
                       maintain pelvic and
                       lumbar alignment (2)

Vehicle transfers

Walking                Single-limb stance:     Single-limb stance:
                       While standing on 1     While standing on 1
                       leg, contract           leg, contract
                       buttocks to maintain    buttocks to maintain
                       level pelvis and        level pelvis and
                       avoid bending trunk     avoid bending trunk
                       to either side          to either side

                       Hold onto high          Perform without
                       counter or chair        support of arms (5)
                       back to assist with
                       balance

                       Perform in front of
                       mirror to monitor
                       performance (3)

Overhead and           1. While sitting in     Perform exercise 1
cross-body reaching       a straight-back      while standing, with
(eg, reaching for         chair, with LB       LB supported against
items located in          supported, begin     a wall and pelvis
overhead cabinets,        with shoulders       tilted posteriorly
reaching for items        and elbows bent      (4)
not directly in           to 90 [degrees],
front of body/            palms facing         Perform exercise 2
raising arms              toward you and       while standing, with
overhead to don/doff      elbows facing        LB supported against
shirt, raising arms       forward. Raise       a wall, and pelvis
to wash or style          both arms overhead   tilted posteriorly
hair)                     while contracting    (7)
                          abdominals so that
                          LB maintains
                          contact with
                          support surface
                          during arm motion.
                          (3)

                       2. While sitting in a
                          straight-back
                          chair, with LB
                          supported, begin
                          with 1 arm
                          overhead, holding
                          a 0.9-kg (2-lb)
                          weight. Lower arm
                          down across body
                          toward opposite
                          hip. Contract
                          abdominals so that
                          LB and pelvis
                          maintain contact
                          with support
                          surface. (6)

Sitting                Posterior pelvic
                       tilts while seated
                       (2)

(a) The patient was instructed to incorporate techniques for functional activity modification into performance of daily activities. In addition to exercises listed in table, the home exercise program (HEP) included performance of the modified version of each symptom-provoking movement test described in Table 2, as well as exercises to lengthen the hip flexors and improve gluteus medius muscle strength. The patient was initially instructed to perform 6 to 8 repetitions of each exercise, 2 to 3 times daily (with the exception of hip flexor stretch, which was performed twice daily for 3 to 5 repetitions, lasting 30 seconds each). Intermittent performance of a relatively low number of repetitions was chosen in order to avoid muscle fatigue and to optimize motor learning through random practice sessions. As the patient's endurance improved, the number of repetitions for each exercise was increased to 10 to 15 repetitions per session. A walking program was initiated in the third therapy session. LB=low back.

(b) All functional instructions were provided during initial visit and were reviewed periodically across the 8 treatment sessions.

(c) Number in parentheses indicate at which visit the patient received instruction in each exercise (8 visits total). In general, exercises were progressed when the patient was able to perform at least 10 to 15 repetitions of initial exercise without verbal or manual cues from the therapist. In no case was an exercise progressed if the patient was unable to demonstrate the modified exercise as instructed and without an increase in symptoms. Upon discharge, the patient was encouraged to adhere to functional activity modifications indefinitely to prevent a recurrence of symptoms. We also suggested that she remain physically active by continuing her HEP and walking program at least once daily.

(d) "Neutral" is defined as that position of the lumbar spine at which an inclinometer centered over each lumbar spinous progress would result in a measure of 0 degrees, without rotation or side bending of any of the lumbar vertebrae.[12]

During subsequent visits, the patient was instructed in a home exercise program to address both functional limitations and specific physical impairments. The patient was encouraged to practice isolated limb movements while avoiding rotation or extension movements of the lumbar spine. This was accomplished through performance of the modified version of each movement test that resulted in symptoms during examination (Tab. 2), as described in the Appendix (shown in the full-text version of this article on the Physical Therapy Web site at http://www.apta.org/pt_journal). The importance of activity modification was emphasized by having the patient perform the majority of exercises both in isolation and during functional movement. For example, the patient was instructed to perform 10 to 15 daily repetitions of the forward bend exercise (Tab. 5), with additional instructions to use this same technique each time she bent forward throughout the day, such as when brushing her teeth. A brief description of each exercise and its functional correlate is provided in Table 5. The importance of maintaining a neutral or slightly flexed position of the lumbar spine through active use of abdominal muscles was emphasized. We believed that this position would prevent an increase in low back-related symptoms and facilitate strengthening of the abdominal muscles.

In addition to the exercise program, the patient was instructed in techniques that we believed would lengthen the hip flexors and improve gluteus medius muscle force production. While lying prone, the patient used a sheet positioned around her ankle to assist in passively flexing her knee to the point at which she perceived a gentle stretch in the anterior thigh. To avoid an increase in symptoms when positioned prone, the patient initially was instructed to position 2 pillows under her abdomen, but eventually was able to perform this stretch in the absence of pillows without an increase in LBP. In an effort to improve gluteus medius muscle force, the patient was instructed in active hip lateral rotation and abduction performed while side lying. As with all other exercises, rotation and extension movements of the lumbar spine were specifically discouraged during the performance of these 2 exercises. Following instruction in gait modifications that we believed would reduce the magnitude of rotation of the pelvis and lumbar spine (Tab. 5), a walking program was prescribed to improve aerobic fitness. The patient reported that modifying her gait reduced her symptoms immediately following instruction. The patient declined referral to a urogynecologist regarding her symptoms of pelvic pain and cramping.

Outcomes

The patient completed 8 physical therapy sessions over a 3-month period. The first 3 sessions were spaced 1 week apart, with subsequent sessions once every 1 to 4 weeks. Her condition was assessed 3 months after discharge through a telephone interview and a mailed questionnaire. A modified Oswestry Disability Questionnaire[33] and a pain diagram were used to document patient-perceived progress once each month, with 1 exception due to an administrative oversight. Patient scores on the Oswestry Disability Questionnaire have been found to be reliable (Pearson r and intraclass correlation coefficients [is greater than] .90)[33,41] as well as related to scores on other accepted measures of disability in patients with LBP,[42] an indication of construct validity of the questionnaire. Reproducibility of pain diagram responses in patients with chronic LBP has been documented.[43] Concordance between defined disorders associated with LBP and diagnoses based on pain diagram responses provides evidence of validity of the pain diagram as a clinical tool.[44] Physical impairment measurements were obtained by the first author during the patient's final therapy session for comparison with initial values.

During her initial visit, the patient received instruction in activity modification only. In the week following this visit, the patient noted a reduction in both the frequency and intensity of her symptoms. She reported a 75% decrease in the frequency of pain in the central low back region and a 40% reduction in the frequency of symptoms in the left lower extremity. She also reported that the average intensity, of her symptoms was reduced from 6/10 to 3.5/10 on a verbal pain scale, with no symptoms present the day of her second session. When asked to describe her activities during the past week, the patient noted a substantial improvement in her ability to perform household chores and in her overall tolerance for physical activity. With the exception of sit-to-supine transfers, we observed adherence to all activity modifications taught in the initial therapy session throughout the second treatment session.

By her final therapy session, the patient no longer experienced lower-extremity symptoms. She noted symptoms localized to the central low back as typically being less than 3/10 when present, with approximately 75% to 80% of her week being symptom-free. She noted that the intensity of symptoms in the central low back region generally increased with increasing fatigue. The patient was able to independently demonstrate all prescribed exercises and activity modifications as instructed, without an increase in symptoms. She reported that she typically performed her home exercise program once daily, and was walking 3.5 to 4.5 minutes each day on her treadmill without an increase in low back-related symptoms.

The modified Oswestry Disability Questionnaire[33] contains items pertaining to both functional limitation and disability and was used in this case to document functional progress. The patient's pretreatment Oswestry score of 43% dropped to 16% by her final therapy session. As interpreted by Fairbank et al,[41] these scores reflect a transition in function from severe disability to minimal disability. In the 3 months following discharge from outpatient physical therapy, the patient did not experience an exacerbation of low back-related symptoms and continued to make functional improvements. Specific examples of functional improvement noted by the patient during the follow-up telephone interview at 3 months included the ability to brush her teeth, get into and out of her truck, and shop for over an hour without an increase in symptoms.

Less consistent changes were observed for measures of muscle force and joint flexibility (Tab. 3). Changes included what we believed to be indicators of increased length of the hip flexors, improved ability to use the abdominal muscles without an increase in pain, and an increase in spinal flexion and extension range of motion. Hamstring muscle flexibility and spinal side-bending range of motion declined over the course of treatment. Estimates of the intrarater reliability of data obtained for these physical impairment measures are provided in Table 3 to the extent that this information is available. However, due to the general lack of documented reliability for many of the physical impairment measures routinely used by clinicians, small changes in the measurements should be interpreted with caution.

Discussion

Numerous interventions are available for patients with low back-related disorders.[45] The challenge for physical therapists is to identify the most appropriate intervention for each patient, based on the findings from a standardized examination. This task is difficult because the etiology of LBP is unknown in the majority of cases[45] and the relationship between physical impairment and disability in this population remains largely undefined.[19]

Our case report describes an intervention that was chosen based on the evaluation of spinal alignment with postures and spinal motions during active movement of both the spine and extremities. Given the documented lack of association between LBP and various traditional measures of physical impairment,[23] we sought to identify a particular pattern of spinal motions and alignments that appeared to be directly associated with a worsening of symptoms across several test positions. We then based intervention on modification of symptom-producing motions and alignments of the lumbar spine during the repetition of daily activities. Despite modest changes in measures of physical impairment (Tab. 3), the patient described in this case report exhibited what we consider a substantial and consistent reduction in low back-related functional limitations and disability (Figure) over the course of treatment. In addition, the most dramatic reduction in low back-related symptoms occurred following the first therapy session, in which the only treatment provided was category-specific instruction in activity modification.

[Figure ILLUSTRATION OMITTED]

Waddell et al[46] found a strong association between low back-related disability and fear-avoidance beliefs, or the extent to which patients avoid activity based on the anticipation of pain. Waddell et al suggested that restricting the activity of patients with LBP might serve only to reinforce fear-avoidance beliefs and increase the chances of subsequent disability. The benefits of maintaining customary activity levels in patients with LBP has been substantiated by the findings of Malmivaara et al.[47] These investigators found that subjects with LBP who were advised to continue their usual routine as tolerated recovered more quickly than those who were prescribed either 2 days of complete bed rest or back mobilizing exercises.

Teaching patients specific strategies to reduce the symptoms associated with movements can enable them to perform activities that they might otherwise avoid. We believe that one of the primary advantages of the classification system described in this case report is that it allows physical therapists to make recommendations for activity modification that are specific to the symptom-provoking postures and movements of each patient. We propose that exercise prescription and generic postural instruction may be less effective in addressing restrictions of function in patients with LBP than is individualized instruction in symptom-reducing strategies for positioning and functional movement. The patient described in this report, for example, was instructed in ways to avoid rotation and extension of the lumbar spine during daily activities. The use of a lumbar roll is one example of a generic therapeutic modality that was discouraged in this case because it would have contributed to spinal extension, an alignment found to be associated with an increase in this patient's symptoms. Greater individualization of back care programs may be needed to facilitate patient adherence.[21] The patient described in this case report noted the greatest adherence to exercises and activity modifications that could be easily incorporated into her daily routine, such as those related to forward bending, walking, and sitting up in bed (Tab. 5).

The treatment approach described in this case report is founded on the notion that the repetition of direction-specific movements and postures of the lumbar spine can exacerbate low back-related symptoms and prolong recovery. The patient exhibited a consistent tendency toward lumbar rotation and extension, which was observed during examination of movements and postures across several positions as well as during the performance of functional tasks (eg, sit-to-supine transfers) and personal habits (eg, "nervous legs"). We have observed that the propensity for spinal motion to occur in a given direction varies among individuals, and we speculate that this variation may be partly related to individual variations in motor recruitment patterns. This idea is consistent with reports of high intersubject variability in trunk muscle activity patterns during a given movement.[48,49] Based on the results of an investigation into the effects of fatigue on trunk motion, Parnianpour et al[50] suggested that the loss of muscular coordination associated with fatigue may diminish spinal stability and allow loading of the spine in a more injury-prone pattern. The patient in this case report commented that she found it more difficult to control the position of her spine and pelvis when she was tired, and she associated an increase in her symptoms with fatigue.

We also have observed that variations in occupational and recreational activity demands appear to contribute to individual differences in direction-specific motions and alignments of the lumbar spine. We suggest that this may be related to changes in supportive structures of the spine that occur with repeated stresses in a given direction over time. A relationship between repetitive spinal motion and LBP is suggested by epidemiologic studies that have identified repetition of non-neutral trunk postures as a risk factor for the development of LBP.[51] In addition, Gordon et al[52] have shown that repetitive loading of spinal segments positioned in a slight amount of flexion and rotation results in pathological changes in the intervertebral disk of the in vitro human spine.

Causal relationships cannot be established on the basis of a case report. Symptoms associated with disorders of the low back typically resolve within 6 weeks of onset, and only 5% of individuals have symptoms that persist longer than 3 months.[51] The LBP episode described in this case report began 10 weeks prior to the patient's initial therapy visit to our facility, which is beyond the time frame typically associated with natural resolution of LBP. Improvement in both functional ability and symptom reduction coincided with the initiation of treatment at our facility. The patient did not experience a recurrence of low back-related symptoms in the 3 months following discharge from our clinic, during which time she continued her home exercise program and activity modifications. Together, these observations suggest that our approach may have positively influenced the patient's recovery. This does not, however, rule out the possibility that the patient might have recovered spontaneously, or responded equally well to another therapeutic approach.

In any isolated case, there are several factors other than the intervention that might account for the observed outcomes. Aerobic training has been reported to be of benefit in the treatment of many disorders, including those related to the low back.[53] Based on reports of the efficacy of aerobic training, a walking program was prescribed during the third treatment session. It seems unlikely that the observed outcomes can be attributed to an improvement in aerobic conditioning, however, given that the patient remained unable to ambulate for more than 5 minutes at one time without becoming short of breath. It might be argued that improvements in hip flexor muscle length could be largely responsible for helping to reduce the patient's symptoms, as lower-extremity flexibility is a commonly addressed impairment in the treatment of LBP. To our knowledge, however, prospective studies have failed to demonstrate a consistent correlation between LBP and hip flexor tightness.[27,54] Because the psoas major muscle is known to impart substantial compressive forces on the lumbar spine,[55] it is conceivable that discouraging the active recruitment of this muscle may have influenced the observed outcome.

Further research is needed to determine the validity and clinical feasibility of the system of classification described in this case report. The theoretical assumptions on which the approach was founded should be investigated to determine construct validity. For instance, is it true that the lumbar spine can become predisposed to excessive movement in a given direction when subjected to repeated stresses in that direction? Examination of whether the proposed classification categories are mutually exclusive and appropriate for use in a rehabilitation context will be necessary to establish content validity. For example, can any patient referred to a physical therapist for the treatment of LBP be classified into 1 of the 5 proposed categories, or does this classification system describe a more limited patient population, such as those with chronic LBP? If the predictive validity of this system could be appropriately demonstrated, then we believe physical therapists could make a substantial contribution to preventative health care. Individuals could be screened for patterns of spinal motion and alignment that may increase the risk of developing mechanical LBP, and they could be provided with specific instruction regarding the modification of such patterns. Other areas of future research should include controlled clinical trials to establish the relative efficacy of individualized versus generic functional instruction, as well as to determine the optimal approach for improving rehabilitation outcomes for patients with LBP.

(*) Glaxo Wellcome Inc, 5 Moore Dr, Research Triangle Park, NC 27709.

([dagger]) Wyeth-Ayerst Pharmaceuticals, Div of American Home Products Corp, PO Box 8299, Philadelphia, PA 19101.

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KS Maluf, MSPT, is Graduate Student, Movement Science Program, Program in Physical Therapy, Washington University School of Medicine, St Louis, Mo.

SA Sahrmann, PT, PhD, FAPTA, is Professor and Associate Director for Doctoral Studies, Program in Physical Therapy, Washington University School of Medicine, St Louis, Mo.

LR Van Dillen, PT, PhD, is Assistant Professor, Program in Physical Therapy, Washington University School of Medicine, Campus Box 8502, St Louis, MO 63110 (USA) ([e-mail]). Address all correspondence to Dr Van Dillen.

All authors provided concept/project design, writing, and data analysis. Ms Maluf and Dr Van Dillen provided project management, and Dr Sahrmann, Dr Van Dillen, and Kate Crandell, PT, MSPT, provided consultation (including review of manuscript before submission). Ms Maluf provided data collection, and Dr Van Dillen provided subjects and facilities/equipment. The authors acknowledge Jennie Levin for help with photographs, Kate Crandell for valuable discussions regarding the management of the patient, and Michael Mueller, PT, PhD, for helpful comments on a previous draft of the manuscript.

This work was approved by the Human Studies Committee of Washington University School of Medicine.

This work was funded in part by National Institutes of Health-National Institute of Child Health and Human Development, National Center for Medical Rehabilitation Research, Grant No. 2 T32 HD07434-04A1 and Grant No. K01 HD01226-01A1.

This article was submitted July 20, 1999, and was accepted July 13, 2000.