Management of Rehabilitation Problems after Total Knee Arthroplasty

Recalcitrant Flexion Contracture (Difficulty Obtaining Full Knee Extension)

• Initiate backward walking.
• Perform passive extension with the patient lying prone with the knee off the table, with and without weight placed across the ankle (see Fig. 4–24). This should be avoided if contraindicated by the PCL status of the arthroplasty.
• Eccentric extension. The therapist passively extends the leg and then holds the leg as the patient attempts to lower it slowly.
• With the patient standing, flex and extend the involved knee. Sports cord or rubber bands can be used for resistance.
• Use electric stimulation and VMO biofeedback for muscle re-education if problem is active extension.
• Passive extension is also performed with a towel roll placed under the ankle and the patient pushing downward on the femur (or with weight on top of the femur) (see Fig. 6–26).
  Delayed Knee Flexion
• Passive stretching into flexion by therapist.
• Wall slides for gravity assistance.
• Stationary bicycle. If patient lacks enough motion to bicycle with saddle high, then begin cycling backward, then forward, until able to make a revolution. Typically, this can be done first in a backward fashion.

Goals of Rehabilitation after Total Knee Arthroplasty

• Prevent hazards of bedrest (e.g., DVT, pulmonary embolism, pressure ulcers).
• Assist with adequate and functional ROM
  • Strengthen knee musculature.
  • Assist patient in achieving functional independent activities of daily living.
• Independent ambulation with an assistive device.

Perioperative Rehabilitation Considerations

Component design, fixation method, bone quality, and operative technique (osteotomy, extensor mechanism technique) will all affect perioperative rehabilitation. Implants can be posterior cruciate ligament (PCL)-sacrificing, PCL-sacrificing with substitution, or PCL-retaining. See the box for advantages and disadvantages of these component designs. 

Continuous Passive Motion

There is conflicting data on the long-term effects of CPM on ROM, DVT, PE, and pain relief. Several studies have shown a shorter period of hospitalization with the use of CPM by shortening the length of time required to achieve 90 degrees of flexion. However, an increased incidence of wound complications has also been reported. Reports vary on whether there is any long-term (1 year) improvement of postoperative flexion in patients using CPM versus those who do not. Transcutaneous oxygen tension of the skin near the incision for total knee replacement has been shown to decrease significantly after the knee is flexed more than 40 degrees. Therefore, a CPM rate of 1 cycle per minute and a maximal flexion limited to 40 degrees for the first 3 days is recommended. If a CPM unit is used, the leg seldom comes out into full extension. Such a device must be removed several times a day so that the patient can work to prevent the development of a fixed flexion deformity.

Deep Vein Thrombosis Prophylaxis

The incidence of DVT after total knee arthroplasty is much higher than originally suspected. Based on clinical detection, the DVT rate after total knee arthroplasty ranges from 1 to 10%. However, more sensitive techniques (radioactive fibrinogen scans) have revealed a much higher incidence (50 to 70%). Prophylactic treatment is indicated (p. 457).

Osteotomy of the Knee

This is a mechanical load-shifting procedure. The mechanical axis of the knee is “shifted” from the worn compartment (usually medial) to the good compartment. Closing wedge osteotomies have an inherent disadvantage in that the tibiofibular joint must be disrupted with some degree of shortening and joint-line alteration. Because the joint line must remain “horizontal,” in OA with a valgus deformity, the osteotomy is done through the supracondylar region of the femur; and for varus deformity, it is done through the proximal tibia. Contraindications to tibial osteotomy include panarthrosis (tricompartmental involvement), severe patellofemoral disease, severely restricted ROM (loss of more than 15 to 20 degrees of extension, or flexion less than 90 degrees), and inflammatory arthritis. There are very few contraindications to a varus osteotomy other than damage to the medial compartment. There are manycontraindications for a tibial osteotomy. Outcome after a valgus osteotomy depends on the varus thrust force.
This force, however, can be detected only by the use of a very sophisticated force plate analysis, of which there are very few available worldwide, and other indications must be used. Strength-to-weight ratio is extremely important, meaning that the older the patient and the heavier they are, the less the indication. A straight tibial diaphysis will result in an oblique joint line. A pagoda-shaped or sloping surface of the tibial plateaus usually produces a bad result. Lateral subluxation of the tibia on the femur and flexion contracture of more than 7 degrees also produce a bad result. No osteotomy will last indefinitely. Supracondylar femoral osteotomies do not interfere with subsequent total knee replacement because the osteotomy is done above the level of the collateral ligaments.
Tibial osteotomy will produce an inferior result with a total knee replacement because the osteotomy is done inside the collateral ligaments and patellar tendons and may produce a patella baja deformity. Eventually, a total knee replacement will be required in these patients. For this reason, osteotomies are seldom done in the United States, although they remain moderately popular in many places in the world. New “opening wedge” techniques with Puddu plate type fixation are currently being evaluated. Their purported value is that the open wedge does not adversely affect the joint line in subsequent total knee replacement.

Nonoperative

Treatment of early OA of the knee may be very effective if conscientiously carried out. Weight loss should be strongly encouraged but not expected immediately. Quadriceps strengthening makes a surprising difference.
Very strong quadriceps can considerably delay the necessity for surgery. If the patella is painful, extension exercises should be carried out only over the last 20 degrees of extension.
Activities such as deep squatting, kneeling, and stair climbing that increase the patellofemoral joint reaction forces (PFJRFs) increase pain. Those activities should be avoided. If the patient starts with extremely weak muscles, electric stimulation may be used to begin the process. Modalities other than heat or cold have not been shown to be of value. Hyaluronic acid injections into the knee are of limited value. They appear to work best before there is bone-on-bone crepitus. Studies by independent researchers have found hyaluronic acid injections to be of “equal benefit” to nonsteroidal anti-inflammatory drugs (NSAIDs) (naproxyn [Naprosyn]). Patrella (2002) purports that hyaluronic acid intra-articular injection was of benefit. Careful review of the study actually reveals that injection of hyaluronate sodium (Synvisc, Provise, and Suplasyn) to be no better than placebo. Similarly, intra-articular steroid injections have a very temporary and limited role. Keating (1993) found that of 85 patients with medial compartment arthritis of the knee, more than 75% had statistical improvement on their Hospital for Special Surgery pain scores at 12 months with the use of a lateral wedged insole in their shoe. For example, a 0.25 inch soft wedge or a 5 degree wedged insole placed laterally will reduce medial joint reactive forces from the medial joint line.

Operative—Arthritic Knee

Arthroscopic débridement is of temporary value, simply cleaning out the tags and meniscal tears and flushing from the joint fluid that contains pain-producing peptides. Cole and Harners’ (1999) article on the evaluation and management of knee arthritis provides an excellent overview on arthroscopy in patients with knee arthritis. Livesley et al (1991) compared the results in 37 painful arthritic knees treated with arthroscopic lavage by one surgeon against those in 24 knees treated with physical therapy alone by a second surgeon.
The results suggested that there was better pain relief in the lavage group at 1 year. Edelson et al (1995) reported that lavage alone had good or excellent results in 86% of their patients at 1 year and in 81% at 2 years using the Hospital for Special Surgery scale. Jackson and Rouse (1982) reported on the results of arthroscopic lavage alone versus lavage combined with debridement, with 3-year follow-up. Of the 65 patients treated with lavage alone, 80% had initial improvement but only 45% maintained improvement at follow-up. Of the 137 patients treated with lavage plus debridement, 88% showed initial improvement, and 68% maintained improvement at follow-up. Gibson et al (1992) demonstrated no statistically significant improvement with either method, even in the short term. Patients who present with flexion deformities associated with pain or discomfort and osteophyte formation around the tibial spines may benefit from osteophyte removal and notchplasty, as démonstrated by Puddu et al (1994). The efficacy of lavage with or without debridement is controversial, and randomized prospective controlled trials have not been performed. The literature suggests that arthroscopic lavage and debridement, when performed for appropriate indications, will provide improvement in pain relief for 50% to 70% of patients, with relief lasting from several months to several years. Drilling and abrasion arthroplasty do not appear to offer additional benefit.
Arthroscopy is also a sensitive way to evaluate cartilage when contemplating osteotomy or unicompartmental knee arthroplasty, as plain radiography and magnetic resonance imaging often underestimate the extent of osteoarthritis. Several factors determine prognosis after lavage and debridement.Those who benefit most present with a history of mechanical symptoms, symptoms of short duration (<6 months), normal alignment, and only mild to moderate radiographic evidence of osteoarthritis. It is not uncommon for patients to have unrealistic expectations after arthroscopic debridement. Thus, it is important to counsel patients about the limited indications and palliative results.

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.

McKenzie Technique
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.

Physical Therapy Approaches in Low Back Pain-Overview of Extension-Flexion Bias

In patients with LBP and concomitant radiating leg pain, McKenzie (1981) has described a clinical phenomenon known as “centralization.” During McKenzie’s procedure, a change in pain location from peripheral (or distal) to a more proximal (or central) location is desired during the mechanical assessment and manipulative evaluation.

Determination of the initial movement pattern to be used by the therapist is based on presumed pathology (e.g., discogenic versus posterior element pain), pain pattern, and successful pain centralization. Again, this underscores the importance of thorough evaluation that allows the physician to accurately categorize the malady being sent to the therapist for treatment as discogenic, posterior facet joint, or something else.

Extension Bias

As a very generalized guideline, the extension bias (see later) is most commonly used with discogenic pathology; symptoms decrease with repetitive extension on motion pattern testing and pain centralizes with extension.

• Extension exercises may reduce intradiscal pressure, allowing anterior migration of the nucleus pulposus away from the area of pathologic compression (Figs. 9–28 and 9–29).
• Extension exercises may actually increase symptoms in patients with large central disc herniation, foraminal stenosis, or foraminal herniation.
• Cardiovascular fitness may then be initiated with an exercise that employs a neutral to extension bias in these patients to avoid aggravation of the patient’s back pain during aerobic exercise (e.g., use of aquatic stabilization training or cross-country ski machine).

Flexion Bias

Flexion bias is most commonly used in patients with posterior spine element (e.g., facet) pain. In these patients, symptoms decrease with repetitive flexion on motion pattern testing and pain centralizes with flexion.

• Flexion exercises (see later) may act to reduce facet joint compression and provide stretch to lumbar musculature, ligaments, and myofascial structures.
• Flexion actually increases intradiscal pressure and exacerbates discogenic symptoms.
• Cardiovascular exercises in patients with posterior spine element pain may be initiated with stationary bicycling in slight lumbar flexion or aquatic stabilization exercises in slight lumbar flexion. These activities place the spine in a neutral to flexion bias.

Clinical Presentation of Spinal Stenosis

Most patients at initial presentation have a long-standing history of lumbar back pain with progression of lower-extremity pain (neurogenic claudication complex). Amundsen et al (1995) reported that the most common symptoms in lumbar spinal stenosis were back pain (95% prevalence) neurogenic claudication (91%), leg pain (71%), and weakness (31%). In 70% of their patients the back pain and leg pain were equally distributed.

There are usually few associated physical findings with spinal stenosis. Amundsen et al (1995) reported sensory changes in 51% of patients, reflex changes in 47%, lumbar tenderness in 40%, reduced spinal mobility in 36%, positive straight-leg raising in 24%, and weakness in 23%. Post-exercise examination (e.g., stair-climbing or walking) may reveal greater motor weakness than a static exam.

The key to correctly diagnosing degenerative lumbar spinal stenosis is to recognize the classic neurogenic claudication history. Patients with neurogenic claudication classically complain of pain, weakness, numbness, tingling, or cramping in 1 or both legs. These symptoms occur with walking or standing; sitting or leaning forward alleviates at least some of the symptoms. Cycling, which involves forward flexion, is also usually tolerated by patients with lumbar stenosis.

Differential Diagnosis

It is also essential, given the paucity of physical findings, to rule out other conditions that may present with low back and/or lower extremity symptoms.

Patients with vascular claudication will have diminished pulses, evidence of peripheral vascular disease, and relief with rest rather than forward flexion. Other conditions that should be considered include peripheral neuropathy, which presents as dysesthesias and paresthesias rather than activity and position-related changes, and arthritis of the hip, which often presents with buttocks pain but should exhibit hip irritability on internal rotation and abduction. Conditions such as aortic aneurysm, knee arthritis, pelvic or sacral pathology, cervical myelopathy, amyotrophic lateral schlerosis, demyelinating disease, depression, or retroperitoneal tumors should be ruled out.

Diagnostic Modalities

Plain lumbar spine films are employed to exclude tumor, fracture, infection, etc. In patients with signs and symptoms consistent with spinal stenosis, MRI or post myelographic CT scans are needed to confirm neural element compression. On myelogram, nerve root entrapment in the lateral recess or central canal stenosis is demonstrated by the level of cutoff of contrast material. Herno et al (1994) found that myelographic evidence of complete cutoff of contrast material (severe stenosis) correlated with a better surgical outcome. Riew et al (1998) concluded that post-myelographic CT is superior to MRI as a single study for the preoperative planning of decompression for lumbar spinal stenosis. Electrophysiologic studies are rarely useful in the evaluation of lumbar stenosis.

Natural history of Non-operative Treatment

Johnsson et al (1992) studied the progression of symptoms over a 4 year period in 32 patients with lumbar stenosis who refused or were not medically cleared for surgery. 70% of patients were unchanged at 4-year follow-up. Of the remaining 30%, half were better, half worse. The results of the prospective Maine Lumbar Spine Study part 3 (Atlas et al 1996) demonstrated superior outcomes at 1 year for operative treatment of symptomatic lumbar stenosis compared with non-operative treatment. The operative patients maintained their superior status at 3 years.

Non-operative Treatment of Lumbar Stenosis

We recommend use of the algorithm employed by Hilibrand and Rand (1999) (Fig. 9–26) for the non-operative treatment of degenerative lumbar spinal stenosis.

NSAIDS are part of the initial management unless contraindicated. Physical therapy is employed using a modification of the standard low-back exercise program. Postural exercises in flexion are combined with pelvic stabilization and aerobic conditioning. Bicycle exercise is recommended because the slight forward flexion is typically well-tolerated by these patients. A back brace fashioned in slight forward flexion may also be useful, but long-term brace wear may eventually lead to truncal deconditioning.

Epidural steroid injection (ESI) is commonly used to treat patients with lumbar stenosis. Cuckler et al (1985) performed a prospective, randomized, double-blind study of epidural steroids in patients with lumbar radicular symptoms, half of whom had a diagnosis of lumbar spinal stenosis. In the spinal stenosis patients, there was no statistical difference in symptom improvement between the ESI and placebo injections at 24 hours and at 1 year. However, a similar study by Dilke et al (1973) demonstrated a statistically significant (p <0.05) improvement in short-term pain and functional measures.

Hilibrand and Rand (1999) reserve the use of epidural steroid injections for mild to moderate stenosis and major medical co-morbidities for whom physical therapy and other medical treatments have not helped.

Operative Treatment (Fig 9–27)

Success rates for surgical treatment of lumbar stenosis have ranged from 57% to 85% (Spengler 1987; Hilibrand 1999). A thorough work-up is recommended to identify any associated degenerative pathologic changes-such as spondylosisthesis, segmental instability, or scoliosis-that might require concomitant stabilization in addition to decompression.

Piriformis Syndrome (Pseudosciatica)

This syndrome results from compression or inflammation of the sciatic nerve as it courses under or through the piriformis muscle in the buttock. The patient presents with pseudosciatica-buttock and leg pain. They have tenderness on piriformis muscle palpation. Fifty percent of patients have LBP; 23% have dyspareunia. To distinguish piriformis syndrome from lumbar radiculopathy, perform a nerve tension test (positive in the latter). To distinguish piriformis syndrome from sacroiliitis, review pelvic radiographs. Sclerosis or irregularity of SI joints should be evident in sacroiliitis (Table 9–8).

Definitions

• Pars interarticularis-the area between the superior and the inferior articulating processes of the vertebra, that is, the point at which the articulating process approaches the pedicle (Fig. 9–25A).
• Spondylolysis-the lytic line that crosses the pars interarticularis. Eventually, slippage of the vertebra may occur (spondylolisthesis) (see Fig. 9–25B and C).
• Spondylolisthesis-the resultant forward slippage of the involved vertebra on the vertebra directly below it (see Fig. 9–25D).

  Spondylolysis occurs most commonly in young children who perform repetitive flexion and extension of the spine (e.g., gymnasts). SPECT scanning often confirms a stress fracture of the pars interarticularis (spodylolysis).

 

Spondylolysis

• Best defined as a stress fracture of the pars interarticularis.
• Hereditary predisposition.
• Often a history of repetitive flexion-extension of the spine (e.g., back-walkovers in gymnasts).
• Symptoms usually include low back and occasionally posterior buttock and thigh pain with no neurologic deficit.
• Single-photon emission computed tomography (SPECT) scan shows area of involvement.
• A single-leg hyperextension “stork test” (see Fig. 9–15) is performed to assess localized spondylolysis pain. The patient stands on one leg with the other foot resting on the weight-bearing knee. The patient then hyperextends the lower back. Reproduction of the patient’s lower back pain indicates a diagnosis of spondylolysis until proven otherwise.

Spondylolisthesis

• “Slip” of one vertebra on another.
• Restricted range of motion of the low back. This is a very important finding in evaluating children.
• Sacral prominence with a palpable “step-off.”
• Lumbar lordosis is lost (lumbosacral kyphosis).
• Tight hamstrings.
• 75% have low back pain.
• Often back spasms.
• “Heart-shaped” buttocks.
• Slip visualized on standing “spot” lateral.
• Goals of treatment are pain relief, arrest of slip progression, and minimizing deformity.
• Treatment alternatives include serial observation, lumbar stabilization exercises, stretching, spica cast, fusion in situ, laminectomy with fusion, and reduction with fusion.

Degenerative Lumbar Spinal Stenosis

• Spinal stenosis classically presents with neurogenic claudication
• Pain exacerbated by standing or walking.
• Pain radiates into buttocks and lower extremities.
• Pain relieved by forward lumbar flexion.

  The presentation is usually a slowly progressive increase in back and radicular symptoms that occur with walking variable distance. You must rule out vascular claudication.

• Patients with vascular claudication usually have a history of smoking, diabetes mellitus, or hyperlipidemia (Table 9–7) and diminished or absent pulses. In Leriche syndrome, the patient presents with buttock vascular claudication and impotence owing to aortoiliac occlusive disease.

Degenerative lumbar stenosis is a common cause of disabling back pain in patients over 50. The general incidence of degenerative lumbar spinal stenosis ranges from 1.8% to 8% (DeVilliers and Booysen 1976). Lumbar stenosis is caused by reduction of the space available for nerve elements due to filling of the spinal canal with hypertrophic tissue. The process begins with degeneration of facet joints and intervertebral disks, resulting in narrowing of the neural foramina and spinal canal. Associated spinal instability (defined as more than 3 mm of motion between vertebrae on dynamic lateral radiographs) or a congenitally narrowed spinal canal may exacerbate the stenosis.

Arnoldi et al (1976) classified lumbar stenosis as congenital, acquired, or combined. The term central stenosis is used when compression of the dural sac is the main component. Lateral stenosis refers to compression of the nerve root in the lateral recess, in the neural foramen, or lateral to the neural foramen (Kirkaldy 1978).

Three types of spinal canals have been described: round, ovoid, and trefoil. Trefoil canals have the smallest cross-sectional area and are associated with the highest incidence of symptomatic lumbar stenosis (Bolender et al 1985).

The most common pathophysiology noted is that as the nerve roots of the lumbar spine traverse the lateral recesses, they are encroached on by hypertrophic facet joints, infolded ligamentum flavum, and a bulging annulus fibrosis. The degenerative stenosing process may also be accompanied by the development of segmental spinal instability. We recommend employing preoperative prone and supine lumbar radiographs to evaluate for possible segmental instability. Documented segmental instability on dynamic views is an indication for concomitant intertransverse bone grafting with the decompression.

Clinical Pearls for Low Back Pain

Disc Herniation

Over 95% of lumbar disc herniation occurs at the L4–5 level (L5 signs) or L5-S1 level (S1 signs). Seventy-five percent of lumbar herniated discs spontaneously resolve within 6 months. Leg pain and paresthesias are more symptomatic than the back pain. Only 5 to 10% of patients with persistent sciatica require surgery. Patients with a documented symptomatic herniated lumbar disc treated with surgery have a 10-times-higher risk of developing subsequent disc herniation compared with the general public.

Acute disc herniation is usually characterized by sudden onset of low back discomfort and radicular pain into the leg.

Facet Joint (Posterior Element) Pain

Fifteen to 40% of chronic LBP is due to facet joint pain. The facet joints of the spine are the interfaces where the posterior elements of one spinal segment contact the posterior elements of the next. Like other synovial joints, they can become inflamed. With lumbar facet syndrome, pain is typically aggravated by lumbar extension (which compresses the posteriorly located joint) and is relieved by lumbar flexion (which separates the joint surfaces). The diagnosis is clinical (no specific imaging or examination studies) and is one of exclusion. Pain often occurs acutely with extension and rotation of the lumbar spine. The pain usually presents as nonradiating lumbar spine pain (at times radiating to the buttock, rare to radiate below the knee). Approximately 80% of patients with facet syndrome have evidence of prior disc disease. Facet syndrome has no localizing neurologic symptoms associated with its presentation. Sudden attacks of LBP is more suggestive of facet joint involvement. Steadily increasing pain is more common with disc lesions.

A dramatic response to facet manipulation suggests facet syndrome clinically. Contrast-enhanced facet injections that give relief during the anesthetic phase are diagnostic for facet syndrome.

Physical Examination of the Lower Back

Several excellent texts on spinal examination are available, including Hoppenfield’s Physical Examination of the Spine and Extremities (1976), Hoppenfield’s Orthopaedic Neurology (1988), and Reider’s The Orthopaedic Physical Examination (1999). Some general guidelines should be followed in the examination of a patient with back pain.

Observation and/or Palpation

• Skin (lipomas, hair over spine—spina bifida) (café-au-lait spots, skintags, neurofibromass for neurofibromatosis).
• Pelvic obliquity or leg-length discrepancy.
• List.
• Scoliosis or kyphosis or lordosis.
• Lumbar lordosis.
• Step-off deformity or flat back syndrome (spondylolisthesis).
• Posture.
• Posterior elements tenderness—facet joints, spinous processes, transverse processes.
• Paraspinous muscles (spasm).
• Iliac crest (traumatic hip pointer or meralgia paresthetica—the latter will have a numb anterior thigh, tender neuroma of the lateral femoral cutaneous nerve at the iliac crest).
• Sacroiliac (SI) joints
• Sciatic notch.
  • Palpation for local tenderness in all areas of referred pain including:
  • Groin.
  • Hamstring.
  • Abdomen.
  • Greater trochanter(s) of the hip(s).

Gait

• Heel-walking (tests ankle dorsiflexors ? L4 innervated tibialis anterior).
• Toe walking (tests gastrocnemius ? L5–S1 disc).
• Antalgic gait or stride length or posture during ambulation.
• Extended hip and flexed knee noted during gait (patients with nerve root irritation will attempt to decrease tension on sciatic nerve by walking with extended hip and flexed knee).
  Range of Motion of Lower Back and Hip Joints
• Lumbar flexion (note pain or restricted motion).
• Lumbar extension (pain or restricted motion often indicates posterior element pathology, such as spondylo- or facet syndrome).
• Lateral bending (pain or restricted motion).
• Rotation of spine (pain or restricted motion).
• Hip FABER examination (flexion, abduction, external rotation of hip) (known as Patrick test) (Fig. 9–3A).
• Decreased flexibility of hamstrings and hip flexors (e.g., possible spondylolisthesis).
  Muscle Strength (Table 9–3)

• Standing
  • Trendelenburg gait (weak hip abductors).
  • Toe walking (gastrocsoleus—L5–S1 disc).
  • Hip extension (gluteus).
  • Heel-walking (anterior tibial muscle).
  • Toe extension (extensor hallucis longus).

• Sitting
  • Hip flexion (iliapsoas)
  • Knee extension (quadriceps).
  • Knee flexion.
  • Hip abduction.
  • Hip adduction.

Tendon Reflexes, Pathologic Reflexes

• Patellar tendon (L4).
• Achilles tendon (S1).
• Beevor sign (rectus abdominus innervation test).
• Babinski reflex (pathologic).
• Ankle clonus (pathologic).
  Sensory Testing
• Dermatomal distributions (Fig. 9–4).
  Nerve Tension Signs
• SLR (Fig. 9–5).
• Lasègue test (Fig. 9–6).
• Crossed SLR test (Fig. 9–7).
• Bowstring sign (Fig. 9–8).
• Slump test (Fig. 9–9).
• Femoral nerve stretch test (Fig. 9–10).
  Nerve Tension Tests
  Straight-Leg Raises Test (see Fig. 9–5)
• SLR stretches the L5 and S1 nerve roots. Therefore, an abnormal SLR suggests pathology of the L5 or S1 nerve root. The sciatic nerve runs down the posterior thigh and is formed by L4, L5, S1, S2, and S3 nerve roots.
• This test is done with the patient lying comfortably flat. The leg is slowly elevated with the knee in full extension (straight). In normal patients, some hamstring tightness will be felt at 80 to 90 degrees of hip flexion.
• In the presence of sciatica or nerve root irritation, the patient complains of shooting pain radiating down the posterior thigh, often into the lower leg.
  Lasègue Test (see Fig. 9–6)
• This test is an adjunct to the SLR. When the patient complains of reproduction of sciatic pain with an SLR, the examiner passively dorsiflexes the foot of the leg being raised. If this dorsiflexion worsens the sciatica, the Lasègue test is positive.
  Crossed Straight-Leg Raises Test (see Fig. 9–7)
• The examiner performs an SLR test on the leg opposite to that with the sciatica. If this is positive (e.g., an uninvolved left leg SLR produces the right-sided sciatica), the result is very sensitive and specific for a herniated L5–S1 or L4–5 lumbar disc.
  Bowstring Sign (see Fig. 9–8)
• The examiner starts the test by performing an SLR test until the radicular pain is produced. The knee is then flexed to 90 degrees, typically relieving the patient’s symptoms. The examiner then places pressure with the fingers over the posterior aspect of the sciatic nerve in the popliteal fossa. If this reproduces the pain, sciatica is confirmed.
  Slump Test (see Fig. 9–9)
• This is a variant of the SLR test and Lasègue test, designed to place tension across the sciatic nerve roots.
• The patient, initially sitting erect, is encouraged to slump forward and then fully forward flex the cervical spine.
• At the same time, the patient performs an SLR.
• The patient then dorsiflexes this same foot (duplicating the Lasègue sign). Repeat for each leg. Reproduction of the radicular pain during these maneuvers is very suggestive of sciatic nerve root tension.
  Femoral Nerve Stretch Test (see Fig. 9–10)
• The femoral nerve stretch test is designed to compress the L2, L3, or L4 nerve roots. Compression of these upper lumbar roots is not common.
• The patient is positioned prone on the table with the knee flexed to at least 90 degrees. The examiner then passively extends the hip by lifting the thigh off the examination table. A positive test reproduces the patient’s radicular pain in the anterior thigh, rather than a mild feeling of tightness.

Rectal Examination (Sphincter Tone)

Five signs that suggest nonorganic pathology (Waddell signs)

1. Superficial or nonanatomic tenderness to palpation
   Patient reports disproportionate pain to extremely light touch, or tenderness that does correlate with anatomic structures.
2. Simulation sign
   Axial compression of the head or rotational simulation maneuver (similar to a standing logroll with no true rotation of the affected area) elicits “pain” despite no actual provocation.
3. 3Distraction sign
   The same test (e.g., SLR supine versus sitting [Fig. 9–11]) performed on the “distracted” patient does not cause pain, unlike when performed on the patient initially and was “very painful.”
4. Regional sensory or motor disturbance
   A nonanatomic distribution of abnormal sensation (e.g., the entire leg) is reported rather than an anatomic, dermatomal distribution of pain or numbness.
5. Overreaction
   Patient verbally or physically reacts in an inappropriate, theatrical manner to light touch or gentle examination.

Other Important Areas That Should Be Examined Simultaneously

• Hip(s) (internal and external rotation testing of the hip to rule out intra-articular arthritic involvement)—pain produced on internal or external rotation of the hip is more indicative of intra-articular hip pathology rather than back origin.
• SI joints (FABER maneuver and palpation of the SI joints to rule out sacroiliitis).
• Abdominal examination (e.g., rule out gallbladder, aortic aneurysm).
• Pulses of lower extremities (rule out vascular claudication).
• Sacrum (fracture, tumor).
• Coccyx (rule out coccydynia).
• Lymph nodes (rule out lymphadenopathy associated with sexually transmitted diseases [STDs], infection, tumor).
• Genitalia or meatus or vaginal discharge (STDs).
  Figures 9–12 to 9–14 and Tables 9–4 and 9–5 illustrate lumbar disc levels, neurologic levels, and associated motor, sensory, and reflex findings.
  We also employ the single-leg hyperextension test (stork test, Fig. 9–15) to evaluate for possible spondylolysis in children performing repetitive spine flexion and extension.

Imaging for Low Back Pain

Plain Films (Fig. 9–16)
The Agency for Health Care Policy and Research guidelines for plain films for LBP:

• Recent significant trauma (all age groups).
• Recent mild trauma (patients older than 50 yr).
• History of prolonged steroid use.
• History of osteoporosis.
• Patients older than 70 yr.

• Plain x-rays in combination with a CBC and ESR are useful in ruling out tumor or infection in patients with low back problems when any of the following red flags are present:

• Prior cancer history or recent infection.
• Fever over 100°F.
• IV drug abuse.
• Prolonged steroid use.
• LBP with rest.
• Unexplained weight loss.

• In the presence of red flags (especially for tumor or infection), the use of bone scan, CT, or MRI is clinically indicated even if plain films are negative (Fig. 9–17). The authors recommend letting the back specialist order these imaging studies.
• The routine use of oblique views on the plain lumbar radiographs is not recommended for adults.
• A bone scan is recommended in nonpregnant patients to evaluate acute low back problems when spinal tumor, infection, or occult fracture is suspected from red flags on medical history, physical examination, corroborative laboratory tests, or plain x-ray findings. Bone scans are contraindicated during pregnancy.
• Note: We also recommend obtaining plain films of the lumbar spine in workman’s compensation and/or litigation cases, on legal (physician protection) rather than medical grounds.