A physical therapy model for the treatment of low back pain.

Key Words: Diagnosis, Low back pain, Low back rebabilitation, Model, Treatment.

CP DeRosa, PT, is Associate Professor and Chairman, Physical Therapy Program, Northern Arizona University, Box 15105, Flagstaff, AZ 86011 (USA). Address correspondence to Mr DeRosa.

JA Porterfield, PT, ATC, is President, Rehabilitation and Health Center Inc, Crystal Clinic, 3975 Embassy Pkwy, Ste 108, Akron, OH 44333, and Assistant Professor of Physical Therapy, Cleveland SLate University, Cleveland, OH 44115.

Low back pain continues to be one of the most prevalent problems in health care today. In many orthopedic physical therapy clinics, patients with low back pain constitute the majority of patients seen for evaluation and treatment. Not only is low back pain one of the most common musculoskeletal problems in industrialized societies, but it is also the most costly, and it is the primary cause of disability in persons under age 45 years.(1-6) The magnitude of the economic burden has been estimated at $40 to $50 billion annually, which includes medical, compensation, legal, vocational retraining, and lost productivity costs.(5) Disorders of the low back have truly reached epidemic proportions. This article explores the epidemiology of the problem, presents evaluation and treatment issues that the clinician needs to address, and proposes a system to standardize the classification and treatments of low back disorders.

In 1987, at the request of the Quebec Workers' Health and Safety Commission, the Quebec Task Force on Spinal Disorders (QTFSD) published a monograph that provided a comprehensive examination of the scientific evidence for the assessment and management of activity-related spinal disorders, those disorders typically caused or exacerbated by movement on postural positions that excessively load the spinal tissues.(7) This report was commissioned because of the increase in physical therapy interventions for low back disorders in Quebec, Canada. Furthermore, the Quebec Workers' Health and Safety Commission was particularly concerned with the wide variation in types and duration of treatment from one institution to another.

The great diversity of assessment and treatment approaches is well recognized by most physical therapists. The proliferation of continuing education courses on evaluation and treatment of low back disorders indicates that there are many different schools of thought. The instructors responsible for orthopedic courses in physical therapy curricula often struggle to introduce the student to a variety of assessment and treatment approaches, even if the various approaches conflict with one another or lack a scientific basis. This diversification of assessment and treatment approaches has occurred simultaneously with the development of new knowledge about the anatomy and biomechanics of the spine (8-15) and remarkable advances in technology (eg, magnetic resonance imaging, computer assisted tomography) that allow visualization of the low back not previously thought possible.

In the decade from 1971 to 1981, the number of individuals disabled from low back pain grew at a rate 14 times that of the population growth.(6) Mooney(16) points out that this growth also occurred in the same decade in which there was a rapid expansion of ergonomic knowledge, labor-saving mechanical assistance devices, and improved diagnostic equipment.

Advances in evaluation and treatment methodologies and increased understanding of the pathological process usually lead to a decrease in the incidence of health problems and to improvement in the effectiveness of interventions.(16) The opposite seems to be the case with low back disorders-as our understanding increases, the problems appear to multiply. The proliferation of new technology and advanced clinical skills for the assessment and treatment of spinal pain has not influenced the overall incidence, morbidity, cost, or disability related to spinal pain disorders.(17)

One might also argue that a more liberal definition of the term "disabled low back" is also to blame. Perhaps the standard for disability has changed over time and patients have perfected their ability to use the "system." This compounds the problem facing clinicians, because they are then faced with an additional, albeit unwelcome, responsibility-deciding that patients are not indicated for treatment because of a perception, often lacking objective measures, that the system is being manipulated. Psychological factors are known to have a great influence on the patient's perception of low back pain, and a patient's psyche has an important effect on the outcome of physical treatment.(18)

In 1987, Waddell,(19) who was awarded the prestigious Volvo Award for outstanding work in the clinical science of spine disorders, encouraged his physician colleagues to consider reappraising their traditional approach toward low back problems. His messages were many. Following are a few of his questions and comments that especially deserve our attention:

1. Is the approach toward low back disorders actually the major problem? Waddell(19) points out that low back pain is a benign, self-limiting condition that is so common it could almost be interpreted as a normal occurrence.

2. Are current methods of intervention appropriate for a disorder that in reality might be considered a fact of life, and does a passive approach toward treatment propagate the problem?

3. What determines the plan of treatment? According to Waddell, once a patient reaches a physician,

.. medical assessment and treatment is influenced more by the patient's distress and illness behavior than by the actual physical disorder. Medical treatment may in theory be prescribed for physical indications, but in practice both conservative and surgical treatment for a poorly understood condition such as low back pain is determined to a much greater extent than most physicians realize, or would like to admit, by the patient's distress and illness behavior.(19)(p635)

Although Waddell is addressing physicians, physical therapists should be able to recognize this same dilemma.

4. Should we treat the patient who has acute pain and the patient who has chronic pain in the same manner? Waddell(19) states that chronic pain is different from acute pain and that we have perhaps failed to completely understand the ramifications of this important difference. He further notes that

.. acute and chronic pain are not only different in time scale but are fundamentally different in kind. Acute pain bears a relatively straightforward relationship to peripheral stimulus, nociception, and tissue damage. There may be some understandable anxiety about the meaning and consequences of the pain, but acute pain, acute disability, and acute illness behavior are generally proportionate to the physical findings .... In contrast, chronic pain, chronic disability, and chronic illness behavior become increasingly dissociated from their original physical basis, and there may indeed be little objective evidence of any remaining nociceptive stimulus. Instead, chronic pain and disability become increasingly associated with emotional distress, depression, faded treatment, and adoption of a sick role. Chronic pain progressively becomes a self-sustaining condition that is resistant to traditional medical management. Physical treatment directed to a supposed but unidentified and possibly nonexistent nociceptive source is not only understandably unsuccessful but faded treatment may both reinforce and aggravate pain, distress, disability, and illness behavior.(19)(p636)

Clinicians who treat patients who have low back disorders should recognize this distinction.

The enormous cost of low back pain is not evenly distributed among all patients. Only 10% of the patients are responsible for 80% of the costs.(5) In order to effectively address the problem, therapists must at least be able to differentiate between acutely injured patients and those with chronic pain syndrome.

Waddell's observations(19) should encourage the physical therapist to scrutinize the physical therapy management of the patient with low back pain. We believe that failure to recognize the natural history of low back pain and the utilization of inappropriate treatments may result in conversion of simple low back pain into low back disability. Therefore, before initiating therapeutic interventions with the patient who has low back pain, the clinician must be able to recognize the difference between low back pain and low back disability.

Assuming a sick role may result in secondary gain for some patients, and this must be addressed by the therapist. Whereas our hard questions in the past have been related to types of treatment, the harder question in the future may be deciding who needs physical therapy.

In an attempt to organize our thoughts about a comprehensive physical therapy strategy to deal with this complex problem, we will address the following five topics: (1) the dilemma of diagnosis, (2) the information gained from the assessment, (3) a patient classification system, (4) the objectives of the treatment process, and (5) a proposed physical therapy intervention model that matches the objectives of treatment to the classification of the patient. Where appropriate, we have proposed an action plan that we feel directly places the physical therapist in a position to be one of the health care professionals helping to curtail the epidemic nature of the problem.

The Dilemma of Diagnosis

The precise diagnosis is unknown in 80% to 90% of patients with low back pain.(20) Nachemson(21) has estimated that only 15% of patients experiencing low back pain for longer than 3 months have some demonstrated patho-anatomic explanation for their symptoms. We believe, however, that clinicians are a lot like patients: both dislike uncertainty. A basic human drive is to search for meaning as the first stage to control.(19) Even though neither the pathologic basis of low back pain nor the anatomic source of the pain have been identified, clinicians often feel compelled to give a diagnosis.

The dilemma of uncertainty appears to be avoided for both the patient and the clinician when a diagnosis is made. According to Waddell,(19) patients and clinicians alike are much happier with even a nominal diagnosis. We tend to forget, however, that often this nominal diagnosis is only a convenient pathophysiologic hypothesis based on examiner bias.

We are cognizant of the arguments for offering a precise diagnosis. The basis of the patient's confidence rests in the practitioner's ability to make the patient believe the practitioner knows what is wrong. We believe the potential exists for a vague" diagnosis to yield a vague" treatment approach, which in turn might yield a "vague" patient response. Conversely, we believe that an "exact" diagnosis based on biomechanics, which may not even be scientifically proven," is perhaps beneficial simply because it makes good sense to the clinician and the patient. The benefit is that a more positive environment for treatment ensues, and the patient is not left with the sense that "no one knows what is wrong with me."

This perspective, however, has resulted in treatment strategies designed around pathophysiologic hypotheses related to dysfunction of particular tissues.(15,22-25) For example, therapeutic intervention is often based on the disk model, following the work of Mixter and Barr(22) and Cyriax(23); the joint model developed in osteopathy and by Maitland(24); and the myofascial syndromes.(25)

These models, which ultimately dictate methods of treatment, are based on the pathology of specific tissues. But are such models adequate for the diagnosis of activity-related spinal disorders?(7) Diagnosing activity-related spinal disorders requires assessment of the biomechanics of the mechanism of injury and the determination of the type of forces and positions that reproduce the familiar symptoms. Tissue-related diagnoses are usually based on radiographic or other imaging findings, or on pathophysiologic hypotheses. At least 30% of asymptomatic individuals, however, show abnormalities in the lumbar spine, as determined by the use of myelographs, computed tomographic scans, and magnetic resonance imaging scans.(19,26,27)

We believe that, at present, identifying with any certainty the exact tissues involved in most low back pain is virtually impossible. We suggest that, in the case of activity-related spinal disorders, the physical therapist's focus should not be on identifying the tissues that are at fault, but rather on determining the mechanical stress or combination of stresses that provoke the familiar symptoms.

There are a myriad of assessment techniques for low back pain syndromes. Some physical examination methods have been shown to yield reasonably reliable measurements.(28-32) What has not been shown, however, is whether these reliable measures are valid and whether they are predictors of treatment response.(20) Segmental hypomobility, hypermnobility, facet syndrome, sacroiliac dysfunction, muscle imbalance, and disk derangement have yet to be shown in any randomized controlled studies to relate to the incidence or severity of low back pain. just as various imaging techniques have revealed deviations from a perceived norm in asymptomatic individuals,(27) we must acknowledge that many measures used by physical therapists have the same shortcoming.

Consider for example the finding of joint hypomobility. Three of the many possible explanations for this finding might be

1. Hypermobility of one segment leads to excessive stresses being placed on neighboring joints, rendering them injured, fibrosed, or dysfunctional.

2. Adaptive shortening of a joint capsule causes decreased mobility.

3. Muscle imbalance results in movement disorders, creating excessive force at one joint and causing decreased function.

These explanations afl have individual merit. The problem, however, of relating these descriptions of hypomobility with back pain rests with developing an accurate reproducible measurement and the recognition of the fact that most asymptomatic individuals have asymmetrical facets of the lumbar spine that may or may not create asymmetrical movement patterns.(33) Although segmental hypomobility may be determined by an examiner, its relationship to the current episode of low back pain cannot be substantiated.

The dilemma of diagnosis for activity-related low back disorders is complicated even further because patients with low back pain often receive many different diagnoses over time.(7) In our experience, it is common for many patients with low back pain to arrive in clinics with three or more previous different diagnoses, each, we believe, representing examiner bias. Patients' back problems have been given such labels as "ruptured disk," trigger points," "ligament sprain ... .. muscle tear," bone out of place ... .. pinched nerve," and "sacroiliac torsion." Such wide variability in terminology and diagnoses makes it virtually impossible to measure the success of low back pain management programs and presumably adds to patient frustration. Having multiple different diagnoses, the patient begins to conclude that perhaps something is seriously wrong to warrant such diversity.

Terms such as "disk disease" and facet joint syndrome," in most instances, are ambiguous because it is difficult to measure these phenomena or to clearly define their contribution to pain in a given patient. Instead, terms such as "low back pain" and "low back pain with referral into the leg" are more well defined and unambiguous.

The QTFSD clearly recognized this dilemma of diagnosis. They recommended only 11 classifications of activity-related spinal disorders.(7) The categories are listed in Table 1.

The QTFSD classification scheme might be useful to physical therapists because it recognizes that, in most instances, naming anatomical structures is nonproductive. We believe a modified version of the QTFSD's categories make them relevant to a scheme for physical therapy diagnosis (Tab. 2).

One compelling reason for the development of a physical therapy classification scheme is that a universally accepted classification scheme for activity-related low back pain would allow for a better method of communicating between physical therapists regarding the appropriateness and efficacy of a treatment intervention and would permit scientific investigation of treatment methods. Multicenter analyses of therapeutic interventions are impossible with the current anatomically oriented diagnoses. This lack of a physical therapy classification scheme does not preclude therapists from continuing to search for ways of identifying the tissues from which pain arises, but the focus of its importance becomes shifted for the physical therapist. We believe that the therapist must accept the fact that, in most instances, it is not possible to identify the tissues that are causing pain.

Information Gained from the Assessment

An appreciation of this trend in diagnosis raises the question: If the anatomical structure cannot be isolated, what information is to be gained from the physical testing used during the low back assessment? As there is no evidence that any specific test can identify the tissues that are giving rise to pain, what purpose can the examination fulfill?

One of the most important decisions the physical therapist makes following an examination of a patient with low back pain is whether the history and physical examination are consistent with activity-related injuries to the low back. This decision allows differentiation between activity-related mechanical disorders, which we believe respond to physical therapy interventions, and nonmechanical disorders, which we believe require referral for further medical evaluation.

As an expert in pathokinesiology,(34) the physical therapist diagnoses movement disorders associated with low back pain via an analysis of posture, adaptive changes resulting in altered spinal mechanics, and patterns of muscle weakness that lead to abnormal loads being placed on the spine. We believe that, when identified during the functional assessment, these movement disorders provide excellent indications for physical therapy.

We propose that the proper intent of the physical therapy low back evaluation should be to introduce various stresses into the low back region in both weight-bearing and non-weightbearing positions for the purpose of reproducing symptoms. When the various stresses provoke symptoms in the standing position, they can then be substantiated or compared with findings elicited with the patient in the supine, prone, and side-lying positions. The analysis of the applied stresses that lead to pain forms the second component of the physical therapy diagnosis. Because most patients with activity-related spinal disorders report that the upright posture is more painful than lying down, we believe that the "nociceptive biomechanics" (ie, those body positions and forces of gravity and movement generated into and through the system that provoke pain) are best analyzed during weight bearing. McCombe et al35 argue that determining movements that reproduce symptoms has good reliability and should be considered in the assessment process.

Because physical therapists have extensive knowledge of spinal mechanics and use various active and passive examination techniques to introduce stresses into the musculoskeletal system, we believe their expertise should be in analyzing and formulating a physical therapy diagnosis based on the reproduction of pain through the application of stresses. Documenting the stresses that stimulate a nociceptive response, including the presence or absence of pain and pain location, helps standardize communication regarding diagnosis between physical therapists, regardless of the examining technique.

Classification of Patients

Classification of a patient's symptoms and history into meaningful, easily understood groups helps provide direction for therapeutic intervention and allows for rational application of treatment. Many groupings are theoretically possible. For a grouping system to be successful, however, an element of simplicity is desirable; that is, it must have nearly universal application across a wide spectrum of clinicians. We believe that the more complex a classification system is, the less chance that measurements obtained with the system will be reliable.

We propose that most patients with activity-related low back pain can be placed into one of three categories (Tab. 3). The first category is the patient with an acute injury. This category is depicted by a patient response to the application of various stresses proportional to both the time since the injury and the physical trauma of the injury. Because we have no reason to suspect otherwise, the healing potential of tissues of the low back should behave like any other connective tissue structures in the body 6 to 8 weeks postinjury. The response of the injury of the low back should therefore react accordingly to the healing process. In the absence of significant forces to cause reinjury during the first 6 to 8 weeks postinjury, the intensity, frequency, and duration of the symptoms should be expected to decrease as the healing process progresses.

The intervertebral disk is distinct from other connective tissues(8,9,11-13,22) in that it does not have the same healing potential as other connective tissues in the spine. Mooney(16) SUggests that acute injuries that never resolve or subside in intensity might be representative of pain of diskogenic origin.

The second category of patient is the patient with reinjury (ie, the patient who has exacerbations of a previous injury). These patients describe low back pain that is similar to the pain they experienced previously. Their descriptions of each episode of pain and of the pattern of pain are relatively consistent. The symptoms often diminish only to recur. These patients may initially have injured their back 4 years previous, but the pain spontaneously disappeared. The following year they may have reinjured the same area, and the pain again spontaneously disappeared. Over the past year and a half they may have reinjured their back four more times, but they were unable to self-manage the pain the last two times and are now seeking medical help. These patients are not experiencing new injuries, rather they are continually applying stress to previously injured tissues. The phenomenon of recurrence of low back pain is well substantiated.(4,36)

The third category of patient is the patient with chronic pain syndrome. In order to properly understand this group of patients, we must clarify and standardize the meaning of the "chronic pain" classification, particularly in regard to the word "chronic." Many patients with symptoms of many months' or even years' duration can still have treatable low back pain. These patients should not be thought of as having chronic pain syndrome. We argue that clinicians must recognize that the word "chronic" in the description "chronic pain syndrome" should not imply a time element. With chronic pain, the primary observation by the examining clinician is the patient's illness behavior and hopelessness.(19) In the patient with true chronic pain syndrome, there is no longer a direct relationship between application of forces generated in the physical examination and the pain response. instead, the patient's complaints are compounded by anguish, disability, illness behavior, emotional upheaval, and discouragement. (19) Therefore, following the patient's history and evaluation, and perhaps after the initial trial course of treatment, the clinician should attempt to place the patient into one of these three categories. The reason for this classification is to form a logical basis for treatment. It is then critical to match the objectives of treatment to the patient classification. To standardize treatment of patients with low back pain, specific objectives that encompass all treatment processes need to be identified.

Objectives of Treatment

In some regards, there appears to be more innovation, ingenuity, and, with some interventions, mysticism, for treatments of the low back than for any other area of the body. How might therapeutic intervention be based on logic as well as science? We propose that there are four independent objectives of treatment, within which all therapeutic interventions can be placed (Tab. 4).

The first objective is to modify pain or promote analgesia. Numerous interventions are available to modulate pain. Electromodalities, thermomodalities, or medications can be effective means to minimize the patient's pain. There is a major difference, however, between relief of symptoms and spontaneous resolution of the problem. It is appropriate to treat pain with the purpose of moving into the subsequent phases of a planned rehabilitation process. In our opinion, the treatment of pain as the primary focus is indicated in only a specific group of patients.

A second objective is to introduce nondestructive forces into the injured anatomical region of the body in order to promote movement or to increase the patient's physical activity. The physical therapist has many techniques for placing controlled, nondestructive stresses into the low back region to facilitate and encourage active movement by the patient in order to expedite the patient's return to physical activity. We feel that an early return to activity has the most significant impact in the long-term management of the patient with low back pain.(19,37) This objective is designed to direct forces into and through the injured region at an intensity, frequency, and duration that does not cause further injury.

The "passive extension press-up" is an example of exercises that are suitable for accomplishing this objective. Although often called an exercise," we feel that the press-up is an active mobilization tool designed to help alter a patient's pain pattern. We believe that it is not an exercise designed to strengthen tissues and improve musculoskeletal and neuromuscular performance. For too long therapists have become engrossed in arguments over whether the effect of treatment is focused on the disk, nerve roots, joints, or soft tissue. These academic concerns have confused the real issue for the patient: the analysis and subsequent effect of this mechanical stress on the pain pattern.

Over the past several years, we have witnessed a proliferation of techniques that have a variety of different labels. Table 5 lists some of the mechanical, manual, and active approaches typically used to promote improved function.

We believe that the reason there is debate over the different techniques, and the reason some clinicians become "disciples" of one particular school of thought, is that each technique has a unique explanation and justification of the result. When challenged, clinicians often seek to justify their rationale based on the uniqueness or dissimilarity of the technique instead of its similarities with other techniques. Instead of pursuing the commonalities, we have become accustomed to protecting the "turf."

For example, we believe a lumbar joint mobilization maneuver cannot only stress the joint. Soft tissue concurrently receives controlled stresses, and afferent input is generated to the central nervous system (CNS). The same can be said for any technique.

We suggest that all of these manual and mechanical techniques result in one or more of the following three physiological responses:

1. Influence on the fluid dynamics of the injured area. it is well recognized that fluid stasis, and an altered chemical environment of the tissues, stimulates the nociceptive system and impedes the healing process. It is very difficult to find any manual, mechanical, or active technique that does not influence tissue fluid dynamics.

2. Generation of afferent input into the CNS. Every technique results in an increase in afferent input into the CNS. Although the patterns of afferent input that occur at the CNS level for various treatments are not precisely known, two common results of enhanced afferent input are modulation of pain and alterations in the state of muscle contraction.38

A change may occur in a patient's movement pattern or in the lumbar or pelvic posture immediately following any of the lumbar techniques. We believe, however, that it is obvious that no chemical bonds have been broken in the connective tissue and that no bones have been "put back in place." What has occurred, in our view, is that a new and different resting tension (set) has been afforded the muscle, which in turn results in a change in the passive or active movement patterns that alters the forces directed into and absorbed by the injured tissues.

3. Modification of connective tissue. We argue that, owing to the inherent strength of connective tissue, this is the most difficult response to achieve using typical physical therapy techniques. Tissue can only be altered if the force applied is continuous and for a prolonged period (ie, sufficient to alter the chemical bonding of the tissue). We believe that any other force that results in motion changes must be a result of influences on the neuromuscular system and its attachments to the connective tissue, rather than on the connective tissue structure itself.

In our view, any of the manual and mechanical lumbar techniques used skillfully and appropriately can be an integral part of physical therapy practice. Clinicians must reconsider previous explanations of the effects of these techniques and begin to base such explanations on advances made in the natural and behavioral sciences. Which technique is used is most likely of secondary importance. What appears most important is whether a particular technique carries a likelihood of enhancing a quicker return to active movement and function by the patient. For too long therapists have viewed such techniques as the end product. The criticism regarding a passive approach toward treatment is justified when such techniques are considered the primary focus of rehabilitation.

The third objective of treatment is to enhance neuromuscular performance (ie, enhancing the muscle's potential to resist deformation, or stiffness,(38) or to react with the desired force in rapid manner to carry out the desired movement or weight-bearing pattern). Progressive resistance exercise programs, stabilization exercises, the Feldenkrais technique, tai chi, workhardening exercises, and functional restoration or physical reconditioning programs are only some of the means currently used to train or retrain the neuromuscular system. Training not only alters the muscle tissue and the connective tissue matrix, but it affects the nervous system as well.(39-41)

We believe neuromuscular retraining is important because it achieves the following:

1. Consistent forces placed on musculoskeletal tissues can thicken the connective tissue matrix,(39,42) enhance neuromuscular conduction,(40,41) and improve the entire neuromuscular mechanism.(43)

2. Muscles often act as shock absorbers in the musculoskeletal system. Neuromuscular training can result in an increased stiffness" of the muscle,(38) which perhaps optimizes the patient's ability to attenuate forces converging into the low back region.

3. If clinicians use the results of the evaluation to teach the patient patterns of movement that minimize stress, then they must develop the neuromuscular system's ability to carry out such nondestructive movements. We contend that training and exercise programs better prepare the individual to self-manage his or her low back problem.

4. Controlled exercise can reduce emotional distress and illness behavior and expedite a return to function. The sooner the patient takes this active approach, the better the chance of self-management, successfully returning to activity, and long-term results. Active exercise programs have been consistently shown to be the most effective means of dealing with the low back problem.(37,4 7)

The last objective of treatment is to biomechanically counsel the patient.(48) If the patient is actively involved in a physical therapy program 3 days per week for 45 minutes per visit, this involvement represents approximately 5% of the time that the patient is active. Realistically, if the patient's activity-related low back disorder is going to be changed, clinicians need to educate the patient to self-manage his or her low back pain during the remaining 95% of his or her daily activities.

The need for patient education is the fundamental reason for focusing the intent of the low back evaluation on the forces or combination of forces that reproduce the patient's symptoms. Patient education, based on an understanding of biomechanics that reproduce pain, is a critical component of any treatment program. The patient and the clinician need to recognize that musculoskeletal injury results in adaptive changes that alter the force-attenuation capabilities of the system. For example, if one were to sustain an injury to the lumbar apophyseal joint, creating articular cartilage damage, then the shock-absorbing and weight-bearing capability of the joint, like any other synovial joint, would be decreased. The prompt return to activity and the setting of realistic goals are essential components of a management strategy. This is often difficult for the patient to accept, because the patient typically expects a permanent "cure." In most situations, self-management is a more realistic goal.

Matching the Objectives of Treatment to Patient Classification

The final management consideration is deciding which category of patients, from the classification scheme presented in Table 3, are indicated for a particular treatment objective (Tab. 6). Clinical experience suggests that some therapeutic intetventions are appropriate for patients in one category, but are not indicated for patients in another category, because the natural course of the problem is unlikely to change. The following is a brief explanation of Table 6.

The acutely injured patient, whose history and physical examination suggest injury commensurate with the known response and time periods for the healing of musculoskeletal tissue, should initially be treated for relief of pain and then with therapeutic techniques designed to facilitate an early return to activity. The intent of treatment is to maximize the patient's healing potential and to restore movement as soon as possible without exacerbation of injury. Many manual and mechanical techniques may be effective as adjuncts to modalities that promote analgesia, but we believe that the natural course of the low back condition will probably not be altered. Instead, these methods should be used with the sole intent of facilitating an early return to activity.

The patient with reinjury must develop the neuromuscular capabilities to assist with self-management of his or her musculoskeletal injury, because there is a high probability of continued recurrence. Enhancing neuromuscular performance is strongly indicated and serves as a treatment goal with this patient population, because the state of their musculoskeletal health is critical if they are to avoid reinjury and maintain function. We contend that biomechanical counseling is also an extremely important objective with these patients, because the limits of the physiological capacity of injured tissue must be recognized and respected. Use of pain modulation techniques or generation of controlled forces in the injured region has very limited indications and is appropriate only if the guidelines for acute injury of musculoskeletal tissues are followed.

In our view, the patient with true chronic pain syndrome can no longer be treated with the emphasis on pain modulation. Instead, the focus should be on augmenting function and on increasing physical activity, especially if changes in functional range of motion and physical work capacity can be measured and provided as feedback to the patient. These changes are not only effective in helping to modify the attention to pain, but also promote well being and a feeling of self-worth in the patient. In our view, the treatment program should address the changes that logically occur in any deconditioning syndrome: mobility, endurance, strength, and cardiovascular changes. This is why enhancing neuromuscular performance is so strongly indicated in this patient population, whereas the other three objectives have little or no indication and have a propensity to perpetuate the syndrome.

Conclusions

The fact that low back pain is an epidemic is well recognized. No one can argue that more research is needed. It is also apparent, however, that evaluation and treatment biases must change and that clinicians must develop a more logical rationale for treatment. Only then can our efforts assist in curtailing the low back problem. We fully recognize that socioeconomic, medicolegal, and symptom-magnification factors must be considered. Changes must occur at these levels and in all aspects of the treatment process if success is to occur. That is why we believe this model is a more appropriate vehicle for facilitating change in the approaches used in the physical therapy management of patients who have low back pain. This model provides a strategy that recognizes the present understanding of the disorder, rather than a reactionary response influenced by reimbursement trends and changing treatment biases. The model also places treatment approaches, both current approaches and perhaps those to be developed in the future, into the context of a physical therapy diagnosis and patient classification.

We are hopeful that this model will be carefully examined, debated, and subjected to tests of reliability by the profession. We suggest change not because of evidence of failure in curtailing the low back problem, but more importantly because such a model acknowledges advances made in assessment and treatment options and recognizes the potential for the development of other advances in the future. In this regard, we believe that the basic framework of the model will endure.

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  Table 1. Quebec Task Force on
Spinal Disorders Classification System
  Category Definition
  1         Pain without radiation
  2         Pain with radiation to extremity,
              proximally
  3         Pain with radiation to extremity,
              distally
  4         Pain with radiation and
              neurologic signs
  5         Presumptive compression of a
              spinal nerve root on a simple
              roentgenogram (ie, spinal
              instability or fracture)
  6         Compression of a spinal nerve
              root confirmed by specific
              imaging techniques  ie,
              computer assisted
              tomography, myelography,
              magnetic resonance imaging)
  7         Spinal stenosis
  8         Postsurgical status, 1-6 months
              after intervention
  9         Postsurgical status, >6 months
              after intervention (symptomatic
              or asymptomatic)
 10         Chronic pain syndrome
 11         Other diagnoses
  Table 2. modified Physical Therapy
Diagnosis Classification(a)
  Category Definition
 1         Back pain without radiation
 2         Back pain with referral to
            extremity, proximally
 3         Back pain with referral to
            extremity, distally
 4         Extremity pain greater than
            back pain
 5         Back pain with radiation and
            neurological signs
 6         Postsurgical status  (<6 months
            or >6 months)
 7         Chronic pain syndrome
 (a)  Based on Quebec Task Force on Spinal Disorders
classification system.
  Table 3. Patient Classification of
Activity-Related Spinal Disorders
  Category Definition
 1        Acute injury
 2        Reinjury/exacerbation of
           previous injury
 3        Chronic pain syndrome
  Table 4. Objectives of Treatment for
Activity-Related Spinal Disorders
  Objective Definition
 1          Pain modulation or promotion
             of analgesia
 2          Generate controlled forces to
             promote nondestructive
             movements
 3          Enhance neuromuscular
             performance
 4          Biomechanical counseling
 Table 5. Approaches used to
Generate Controlled Forces
  Type of
  Approach        Approach
  Manual          Categories of massage
                  Joint mobilization
                  Manipulation
                  Soft tissue mobilization
                  Myofascial techniques
                  Traction
                  Stretching
                  Cross-friction
                  Rolfing
                  Acupressure/acupuncture
  Mechanical      Traction
                  Mobilization tables
                  Treatment wedges/rolls
                  Heel-lifts
                  External supports
  Active          Muscle energy
                  Strain/counter-strain
                  Extension/flexion protocols
                  Contract/relax