- About Low Back Pain
- The Development of Low Back Pain
- Considerations for Evaluation of Patients with Low Back Pain
- Physical Examination of the Lower Back
- Disc Herniation and Facet Joint Pain
- Spondylolysis, Spondylolisthesis, and Pars Interarticularis Injuries
- Lumbar Stenosis – Diagnosis and Treatment
- Overview of Extension-Flexion Bias
- Exercise Programs for Low Back Pain
Several exercise programs have been developed for acute LBP. These include those designed by McKenzie (mainly extension exercises) (1981), Williams (1937), Aston (1999), Heller (1991), and Feldenkrais (Lake 1985), and other lumbar stabilization programs, stretching regimens, and aerobic conditioning programs.
The McKenzie technique is one of the most popular of the many conservative spine care programs. It is a method of diagnosis and treatment based on movement patterns of the spine (Fig. 9–30). For any spinal condition, certain movements aggravate the pain and other movements relieve the pain. Because the McKenzie method works best for acute back pain that responds to lumbar extension, mobilization, and exercises, the technique has been erroneously labeled an extension exercise program. McKenzie, in fact, advocates position and movement patterns, flexion or extension, that best relieve the patient’s symptoms.
McKenzie’s method is complex and much has been written explaining its theoretical basis. In The Lumbar Spine: Mechanical Diagnosis and Therapy (1981), McKenzie classifies LBP based on spinal movement patterns, positions, and pain responses, and describes a postural syndrome, derangement, and dysfunction. Each classification has a specific treatment that includes education and some form of postural correction. A basic explanation of the method is as follows.
Some stages of the lumbar degenerative cascade create symptoms because of pathoanatomic abnormalities, which can be positively altered by spinal positioning. This hypothesis has led to several forms of spinal manipulation, including chiropractic and osteopathy.
The McKenzie technique is a more passive form of spinal manipulation in which the patient produces the motion, position, and forces that improve the condition. Examples of pathoanatomic alterations include a tear in the annulus and acute facet arthritis. Repeated lumbar extension may reduce edema and nuclear migration in an annular tear or may realign a facet joint in such a way as to reduce inflammation and painful stimuli. Through trial and error, the position and exercise program that best relieve the patient’s symptoms can be found (see Fig. 9–30).
Cyclic range of motion exercises (usually in passive extension) are the cornerstone of the McKenzie program. These repetitive exercises “centralize” pain, and certain postures prevent end-range stress. Lumbar flexion exercises may be added later, when the patient has full spinal range of motion.
Treatment is based on evaluation of pain location and maneuvers that change the pain location from referred to centralized (Fig. 9–31). Once identified, the direction of exercise and movement (such as extension) is used for treatment. Centralization, as McKenzie use the term, refers to a rapid change in perceived location of pain from a distal or peripheral location to a proximal or central one. Donelson and colleagues (1990) reported centralization of asymmetrical or radiating pain in 87% of patients during the first 48 hours of care.
For a movement to eventually centralize pain, it must be performed repetitively, because the initial movement often aggravates or intensifies the pain. Centralization also occurs more rapidly if the initial movements are performed passively to end-range. Centralization most frequently occurs as a result of extension movement, occasionally from lateral movements, and only rarely with flexion.
McKenzie reported that 98% of patients with symptoms for less than 4 weeks who experienced centralization during their initial assessment had excellent or good results; 77% of patients with subacute symptoms (4 to 12 weeks) had excellent or good results if their pain centralized initially. The critical clinician should always bear in mind the self-limited course typical for patients with low back pain (e.g., a 90% resolution rate at 6 weeks).
The advantage of this program is that it gives patients an understanding of their condition and responsibility for maintaining proper alignment and function. Disadvantages are that the program requires active, willing participation of the patient, who must have the ability to centralize the pain; better results are obtained for patients with acute pain than for those with chronic pain, and the very complex regimen requires a therapist trained in McKenzie’s techniques to obtain the best results.
Each movement is taken to its end-range repetitively as long as distal pain continues to diminish. McKenzie stresses the importance of taking the movements to the end-range permitted by the patient to accurately observe changes in the pain pattern. If distal symptoms worsen, that specific movement is discontinued. Pain locations from these maneuvers are carefully observed and recorded.
Based on the clinical response to centralization, the patient is taught to perform home spinal exercises in that direction of movement (usually extension). For example, for a patient with acute pain, the self-care exercise program may include prone extension for a few seconds at a time, with sets of 10 repetitions performed every hour or two. The patient is also taught modified resting positions (for sitting, standing, and lying) and work postures that will maintain centralization and avoid peripheralization.
Most patients have centralization of pain in the first 2 days or sooner. Again, treatment outcomes in “centralizers” are typically good.
McKenzie classified lumbar movements that have the potential to centralize symptoms into extension, flexion, lateral bending, rotation, and side-gliding (combination of lateral bending and rotation). These may be used individually or in combination to diminish the peripheral pain. Gravity-elimination (prone) versus gravity-assisted (standing) symptom reduction further increases the number of lumbar movement combinations that the therapist must understand and possibly use in an effort to centralize symptoms. The result is that more than 40 different exercise regimens are available, and application of the appropriate regimen may require complex customization.
Williams Flexion Exercises (Fig. 9–37)
The goals of this isometric flexion regimen, developed in the 1930s, are to (1) widen the intervertebral foramina and facet joint to reduce nerve compression, (2) stretch hip flexors and back extensors, (3) strengthen abdominal and gluteal muscles, and (4) reduce “posterior fixation” of the lumbosacral junction. A concern with this method is that certain flexion maneuvers increase intradiscal pressure, possibly aggravating herniated or bulging discs. According to Nachemson (1981), Williams’ first exercise increases intradiscal pressure to 210% over that in a standing posture (see Fig. 9–35). Three of the six exercises increase intradiscal pressure, and these three are contraindicated for patients with acute herniated disc.
Lumbar Stabilization Programs
There is no evidence that early return to activity increases the likelihood of back pain recurrences. On the contrary, physically fit individuals have fewer and shorter attacks of LBP and are more tolerant of pain. With a better understanding of spinal biomechanics, specific activities, and positions that increase loads on the spine, reinjury can be avoided. Numerous studies have shown that patients with LBP can perform selected activities almost normally without increasing pain. Body mechanics that avoid painful positions are called cautious or preventive body mechanics. Body mechanics that attempt to overcome the condition with muscular effort and knowledge of body positions have led to the field of stabilization training.
Back schools, which gained prominence in the 1970s, gave education and training in cautious or preventive body mechanics for routine daily activities, but they did not provide techniques for heavy laborers or for highperformance athletes, who require dynamic, ballistic body mechanics for high-level activities. Practitioners with backgrounds in martial arts or sports training and some therapists with European influences in training developed stabilization training primarily for these patients.
The basic premise of stabilization training is that an individual with back pain (considered an unstable condition) can be taught to stabilize the painful pathologic condition through muscular development and movement patterns that allow painless return to a higher-than-normal level of functional activities. Stabilization training incorporates almost all aspects of conservative treatment: education, body mechanics, manual therapy, the McKenzie technique, Williams’ exercises, yoga, martial arts, work hardening, and functional restoration. The techniques of stabilization training have been extensively demonstrated in many texts and videotapes, and the techniques are used by many therapists who treat high performance athletes with back problems.
The main goal of the lumbar stabilization program is to build musculature that stabilizes the torso, with cocontraction of abdominal muscles to provide a corseting effect on the lumbar spine. This concept is centered on the assumption that an injured lumbar motion segment may create a weak link in the kinetic chain, with subsequent predisposition to reinjury. This program is used in conjunction with other methods aimed at controlling acute pain (such as NSAIDs). Emphasis is on positioning the spine in a nonpainful orientation, termed the neutral spine. Stretching and range of motion exercises are then completed daily in this configuration. Supervision by an appropriately oriented trainer is advised.
The second phase of treatment consists of active joint mobilization methods, including extension exercises in prone and standing positions, and alternating midrange flexion extension in a four-point stance. Simple curl-ups for abdominal muscle strengthening is progressed to dynamic abdominal raising. This includes “dead bug” exercises, using alternate arm and leg movements while supine. Diagonal curl-ups and incline board work are performed.
Progression to aerobic exercise, exercise with a ball, and weight training may be added (see box later). The program endpoint is determined by maximal functional improvement, the point beyond which no further improvement in function will result from additional exercise.