REHABILITATION EVALUATION AND TREATMENT IN PATIENTS WITH LOW BACK PAIN

REHABILITATION EVALUATION AND TREATMENT IN PATIENTS WITH LOW BACK PAIN

Michael Kaplan, MD

ASSESSMENT OF LOW BACK PAIN SPINAL MOTION

• Accurate measurement is very important.
• Limitation of spinal motion correlates with the presence of lower back disability.
• Identification of palpable spasms and understanding nerve innervation are essential.1

PALPATION

• A positive Larson test, performed with the patient in the prone position, can indicate segmental instability common in degenerative disease of the lower lumbar discs.
• Active splinting of the segment reduces or eliminates the tenderness elicited with pressure over the spinous
processes, which is suggestive of segmental instability.
• Tenderness from soft tissue injuries persists despite active splinting.
• Muscle spasm is defined by the presence of a persistent, palpable increase in muscle tone accompanied by
localized tenderness.
• A digital rectal evaluation can detect pelvic floor myalgia or another pelvic pathology.
• Gentle and systematic palpation of the coccyx, sacrum, levator, ani, coccygeus, and piriformis muscles and their associated ligaments and attachments should be performed.

NEUROLOGIC ASSESSMENT

• Straight leg raising (SLR) tests should be performed to detect nerve root irritation. The classic positive SLR
test is a reproduction of radicular pain at 30°–40°.

• Radicular pain reproduced at greater angles represents less significant nerve root irritation.

• Back and leg pain can be produced in the absence of nerve root irritation.

• Nonradicular pain may be caused by soft tissue tightness or spasms in the back, glutei, or hamstrings.

• Even with a soft tissue pain source, the SLR can still be used as an index of improvement during treatment.

• A positive crossed SLR test has the highest correlation with myelographic findings of a herniated disc.

• Significant inconsistency observed during sitting and supine SLR tests may provide insight into the psychogenic processes.

• Electromyography is a valuable adjunct in delineation and confirmation of neurologic findings.2

SPECIAL TESTS

• The Hoover test is of special interest and suggests the detection of malingering because it indicates the recognition of submaximal effort. The jolt test is a provocative method used to document pain enhancement or radiation due to sudden mechanical loading of the erect spine. While standing on tiptoes, the patient is asked to suddenly drop to a flat foot position.
A positive jolt test is characterized by an exacerbation or radiation of pain.

• Leg length can be measured from the anterior superior iliac spine to the prominence of the medial malleoli (true leg length) or from the umbilicus to the medial malleoli (apparent leg length).

TRUNK STRENGTH

• Abdominal oblique muscles can be graded with the trunk rotated, as when a situp is performed.

• A similar method can be used to grade back extensors: lying prone with a pillow under the abdomen and hips, the patient extends the trunk and holds against resistance applied by the examiner.

RADIOLOGIC TESTS

• Plain radiography remains the cornerstone of radiologic tests.

• Plain radiography allows visualization of degenerative disc disease, spondylitis, compression fractures, metabolic bone disorders, bone tumors, congenital anomalies, and transitional vertebrae.

• Oblique views of the lumbosacral level can be added to visualize the facet and sacroiliac joints.

• Flexion–extension views are frequently added whenever spinal instability is suspected.3

COMMON BACK SYNDROMES DEGENERATIVE DISC DISEASE WITH ASSOCIATED DEGENERATIVE JOINT DISEASE OF THE LUMBAR FACET JOINTS

• Degenerative disc disease is a consequence of the aging process and is, therefore, among the most common causes of mechanical back pain in middleaged
and older patients (Table 60–1).

EXAM

• Onset is insidious, and pain gradually increases with prolonged standing or sitting. Pain decreases when the patient is upright, moving about, or lying in the fetal position. Leg or foot radiating symptoms are minimal, and there are no cough/sneeze effects.

• The pain is located in the lumbosacral triangle and upper buttocks.

• The pain is symmetric and causes mild reduction in lumbar flexion as well as right and left trunk rotation and a moderate reduction in lumbar extension and lateral flexion bilaterally.

• Extension is the greatest arc of motion that increases pain.

• The Schober flexion test is 4.5 cm (normal is >5 cm).

• Lumbar lordosis is normal but fails to reverse on full voluntary flexion.

• Gait and heel-and-toe walking are normal.

• Radiographs reveal narrowed disc spaces at L4–5 and L5–S1, sclerosis of the facet joints, and hypertrophic changes.

• When disc material degenerates, the soft semiliquid, gel-like, hydrophilic nuclear pulposus is slowly replaced with a denser, less hydrophilic, less compressible, granular fibrous tissue.

• Degenerated discs also result in narrowing of the intervertebral spaces.

• Tolerance of vibration-related stress is particularly reduced.

PHYSIATRIC INTERVENTIONS

• Williams’s exercises are the most popular lower back exercises (flexing the spine and reducing lumbar lordosis reduce axial loading on pain- and pressure-sensitive posterior spinal structures, such as the facet joints, which, in turn, reduce pain due to mechanical loading of these structures). Back flexion exercises, therefore, play a prominent role in the management of lower back pain secondary to degenerative disc disease.

• Trunk strengthening exercises improve the mechanical efficiency of the spinal muscular support system.

• Particular attention should be given to strengthening the abdominal oblique muscles, if strengthening is
prescribed, as they are the major contributor to increased interabdominal pressure generated by trunk muscles during heavy lifting.

• Strengthening spinal extensors improves the efficiency of shock absorption by concentric and eccentric activity of the intersegmental spinal extensor muscles.

• Trunk strengthening should be predominantly isometric to reduce stress during active flexion in isotonic activities, such as situps.

• Lumbar supports can provide some reduction in mechanical stress on the lumbar spine by substituting for inactive or weak trunk musculature but should not be used routinely as they promote weakness in unused muscles.

• Lumbar rolls and pads are frequently used to increase sitting tolerance. Soft, shock-absorbing shoe inserts also reduce impact stress on the feet.

• Lumbar traction using a simple bar-hanging or pelvic gravity suspension device or any other gravity or lowfriction controlled method may reduce lumbar facet loading and segmental muscle spasm but requires supervision.

• Essential interventions must include alterations in posture and improvements in body mechanics to minimize mechanical stress during daily activities.

• A rational exercise prescription for a patient with degenerative disc disease may, therefore, include:

Flexion exercises

Isometric strengthening of trunk muscles

Bar-hanging traction

Lumbar roll for sitting


TABLE 1 Signs That Aid in the Diagnosis of the Cause of Low Back Pain

DIAGNOSIS                          PAIN INCREASED                        PAIN DECREASED

Degenerative disc                      Positive Larson test                           Knees and hips flexed
with incomplete                          (segmental  instability)                                   (sitting)
lordosis
                                                   Extension

Disc “protrusion”                       Positive Schober                              List to contralateral side                   loss lordosis                              <5 cm
unilateral                                   Flexion                                             Extension standing
                                                Sitting                                               supine
                                                Crescendo/increasing pain                 Knees and hips flexed

Spinal stenosis                          Bilateral leg pain when walking            Sitting
                                                                                                          Squatting
                                               Standing                                              Flexion
                                               Extension

Complete reversal                   Spondylolysis positive                          Lumbar–sacral rigid
lumbar lordosis                        reversal lordosis                                  bracing

Spondylolisthesis                     Schober WNL
                                               Extension
                                               Positive step-off test
                                               Positive Larson

Acute facet                              Localized pain                                    List with rotation to opposite side

                                               Sudden onset
                                               Lateral bend same side
                                               Extension

Strain syndrome                      Tenderness in multifidus muscle           List to ipsilateral side
                                              No segmental step-off
                                              (negative Larson)               


Lumbar support for repeated or heavier chores

Shock-absorbing shoe inserts

Heat

Cryotherapy and analgesics for acute flares

Patient education in posture and body mechanics4

LUMBOSACRAL STRAIN SYNDROME, MULTIFIDUS STRAIN (LORDOSIS) EXAM

• Pulling in the back and left buttock immediately after transfer causes a constant pain of increasing intensity
and stiffness.
• There are localized pain in the lumbosacral triangle, tenderness, and a slight list to one side; a slight antalgic gait; and a normal lordosis with incomplete reversal of lordosis on active trunk flexion.
• SLR tests are limited to >40°.
• The pain is probably due to muscle and ligament strains or facet joint sprains and usually resolves
spontaneously without sequelae with curtailed activities and additional rest.

PHYSIATRIC INTERVENTIONS

• Bed rest is not always necessary. The traditional, fullweek, bed rest trial for acute discogenic disorders may
be inappropriate for acute muscle ligament or facet strains. Recent studies have shown no advantage with a prolonged period of bed rest.
• Activity is restricted, with a prescription for a soft lumbosacral support.
• Adherence to good posture is emphasized.
• Local heat cryotherapy, analgesics, and deep sedative massage may provide adjunctive temporary relief.
• Facet strains will likely heal if reinjury is avoided while healing is occurring. Some lumbosacral strain
syndromes persist, and a few become chronic, possibly because of larger tears of muscles and ligaments.
• Prolonged or habitual muscle spasm may cause additional pain. An aggressive therapeutic program of deep heat, soft tissue mobilization, and muscle relaxation techniques, together with gentle, but progressive,lumbar stretching and isometric strengthening, may abort more ominous chronic back strain syndromes.

General strengthening, with emphasis on knee extensor and leg strengthening, endurance training, and adoption of proper body mechanics are useful interventions.

• Physiatric treatment occurs in conjunction with maintenance of modified, appropriate work and activity
levels.5,6

ACUTE LUMBAR DISC PROTRUSION (FREQUENTLY ACUTE LEFT L5 OR S1 RADICULOPATHY)

• Lumbar disc protrusions are due to degenerative or traumatic weakening and subsequent tearing of the anulus fibrosus.

EXAM

• This condition begins with deep, nagging pain in the lower back and posterior thigh. The next day, the patient is unable to straighten up and experiences pain in the lower back, buttock, posterior thigh, calf, and heel.
• Examination reveals localized pain to the lumbosacral triangle (one side more than the other), buttock, posterior thigh, and calf to the heel and lateral foot.
• The patient loses lumbar lordosis and develops an antalgic gait.
• Marked restriction occurs in trunk flexion and lateral flexion due to pain and moderate reduction occurs in
all other arcs of motion.
• The jolt test is positive with radiating pain.
• Ankle jerk is diminished on the affected side.
• SLR causes lower back, left leg, and foot pain at 30°–40° or less.

MANAGEMENT

• Intradiscal pressure is reduced, allowing the nucleus material to retract and the associated edema of the
nerve root to resolve.
• Strict bed rest is the most effective way to reduce disc pressures for an appropriate time.
• Oral analgesics are appropriate. Muscle relaxants, such as benzodiazepines, may be necessary, and their
sedative side effects may improve psychological tolerance to enforced bed rest during the active phase.7,8
• Local heat may be effective in reducing associated muscle spasms.
• A bedside commode with armrests is preferable to bed pans for bowel and bladder care.
• Attention to proper body mechanics as well as a soft lumbar orthosis applied in bed before getting on the commode may provide support during toileting. Stool softeners and high-fiber foods or supplements reduce constipation.

PHYSIATRIC INTERVENTIONS

• Bed positioning should be arranged to avoid excessive lumbar flexion.
• Slight flexion may reduce small protrusions by tightening annulus fibers.
• Larger protrusions may not reduce with flexion, and some may instead protrude more if the annulus tear is large.
• Flexion of the hips and knees is allowed to reduce stretching of the nerve root over protruded disc material.
• The upper trunk should not be higher than the pelvis, except during meals, to avoid axial loading during the
acute phase.
• Sitting is associated with high intradiscal pressure (more than double that of lying supine and 40% higher than when standing).
• The lowest intradiscal pressure occurs in a supine position with 90° hip and knee flexion.
• Attempts at reducing a disc protrusion with a progressive passive spinal extension program can be made in selected cases.
• A flexed position shifts vectors posteriorly, and extension may shift vectors anteriorly, reducing forces that
are favorable to posterior or posterolateral protrusion.
• Appropriate lateral shifting may centralize lateral vectors.
• A small lumbar roll or pad may help maintain extension while supine.
• Lying prone may help reduce small disc protrusions.
• Lumbar traction is based on the premise of reduction of intradiscal pressure or the creation of a negative
intradiscal pressure with the application of external distracting forces.
• External forces best exceed 50% of body weight to overcome body surface friction.
• Low-force traction (less than 20 kg) simply serves to keep the patient in bed.
• Heavy lumbar traction systems can reduce intradiscal pressures, but they cannot be tolerated for long periods.
• The prescription for an acute disc protrusion with severe symptoms could include 7 days of enforced
bed rest; careful bed positioning; analgesics; muscle relaxants; stool softeners; a bedside commode; a progressive, passive extension program; and possible, periodic heavy lumbar traction.9
• Surgical intervention is reserved for patients who fail such a rest trial or those with progressive neurologic
deficits, bowel or bladder involvement, or intractable pain.

EXERCISES

• The postrest management strategy includes gradual (not precipitous) and progressive mobilization (ambulation) of the patient from bed rest. Intradiscal pressure is higher during sitting than standing or walking,
and when total bed rest is over, the patient should be helped to stand and walk. Ambulation with an assistant,
walker, cane, or in parallel bars can transfer axial loading from the spine to the upper extremities. Soft
lumbar support can further reduce intradiscal pressure while mobilizing the patient.
• Prolonged sitting should be delayed.
• Flexion and isometric exercises and bending, twisting, or lifting should be delayed until the annulus tear
has had adequate opportunity to form a good scar, at least 6 weeks.
• At 6–8 weeks, if there is no sign of disc protrusion, root irritation, or muscle spasms, a very gentle isometric exercise program should commence.
• Patients are also instructed in ways to wean themselves from a corset or other assistive device.
• A protruded disc, even if managed successfully, will inevitably develop into a degenerative disk.

SPINAL STENOSIS (PSEUDO-CLAUDICATION)

EXAM

• Pain is worse with standing and especially worse with walking.
• Pain is often associated with a sensational weakness and numbness in both legs.
• The patient can walk 50–60 m before the pain prevents further walking.
• The patient gets prompt relief by sitting down and bending forward or squatting (relief by standing once ambulation is halted may suggest vascular etiology and lower-extremity symptoms).
• Lumbar lordosis decreases.
• Ankle jerks decrease or are absent on one or both sides.
• The condition is a consequence of advanced degenerative hypertrophic changes in a narrow spinal canal.
• The characteristic feature is claudication-like leg pain or weakness when walking relieved by rest and especially by spinal flexion.
• Surgical decompression is indicated if symptoms are sufficiently limiting, and the patient is medically able.

PHYSIATRIC INTERVENTIONS

• If surgery is ruled out, a program of flexion exercises and use of a lumbar corset, flexion jacket, or William brace and cane may reduce the neural element irritation.
• Shock-absorbing shoe inserts may help.
• Use of a transcutaneous electrical nerve stimulator during ambulation may further reduce pain but will not affect weakness or numbness.

BILATERAL SPONDYLOLYSIS WITH LOW-GRADE SPONDYLOLISTHESIS

• Spondylolysis does not usually cause symptoms; its consequence, spondylolisthesis, is frequently sympto-matic, either from its associated mechanical instability or from traction on or compression of neural elements.

EXAM

• Pain is worse after jumping.
• Pain persists for days after exercise.
• Rest in bed for 2–3 hours usually relieves pain.
• During the past several months, pain has been constant.
• The pain has stopped exercise activity.
• Pain is bilateral in the midline, lower back.
• Pain extends to upper thighs.
• Pain is increased only on extension.
• There is no lateral list.
• There is complete reversal of lumbar lordosis on active spinal flexion.
• Deep tendon reflexes are normal.
• SLR test is negative.
• There is localized tenderness in the involved interspace, typically L4–5 or L5–6.
• Slight palpable step-off is detected at the same level.
• Jolt test is positive.
• Lumbar radiographs show (pars defect) spondylolysis and a spondylolisthesis at the level anterior or retrograde step-off. This is accentuated by flexion or extension on x-ray films.

MANAGEMENT

• Spondylolisthesis is graded according to Meyerding by the percentage of displacement of one vertebral
body: grade 1= 25%, grade 2 = 26–50%, grade 3 = 51–75%, and grade 4 = 76–100%.

• Surgical fusion is not always successful.

PHYSIATRIC INTERVENTIONS

• Effective nonsurgical treatment is available for lowgrade spondylolisthesis. This involves a conservative program to reduce the lumbosacral angle and, thereby, reduce the anteriorly directed shear force on supporting soft tissues.
• A spine flexion program is appropriate and effective to maintain function.
• Therapy includes flexion exercises, posture training with emphasis on minimizing lumbar lordosis, isometric abdominal strengthening, and a lumbar support.
• Extension exercises are contraindicated.
• Bar-hanging and gravity traction systems in a flexed spine position may produce additional symptomatic relief but should be used with caution and may increase symptoms.
• Soft shock-absorbing shoe inserts are indicated.
• Activities that increase lordosis or are associated with sudden jolts should be avoided.
• Marked degenerative disc disease can cause spondylolisthesis without spondylolysis.
• Retrolisthesis, reverse spondylolisthesis, can also occur in the mid- and upper lumbar spine with significant degenerative disc disease.
• Management of degenerative spondylolisthesis is most similar to that of degenerative disc disease, with emphasis on isometric strengthening of trunk musculature and use of a lumbar orthosis. Surgical intervention is not frequently indicated. Spondylolisthesis may also result from multiple-level laminectomies.

ACUTE FACET SYNDROME

EXAM

• There are recurrent episodes of acute back pain.
• A sharp catch occurs when bending and twisting at the same time and then attempting to straighten up.
• A click is evident.
• Heavy lifting is not typically involved but bending backward and twisting are.
• Sudden-onset pain occurs when attempting to straighten from a flexed and twisted position (in contrast to disc protrusion pain, which involves a slow crescendo over several hours).
• Pain from acute muscle and ligamentous strain is not intense on onset but builds over minutes or hours.
• Acute disc herniations and acute facet syndromes cause the patient to list to the side opposite the pain.
• The painful arc pattern for a disc protrusion is pain on flexion.
• The painful arc pattern for muscle or ligamentous strain is pain with flexion, lateral flexion, and rotation to the opposite side (the motions that stretch the involved ligament or muscles) (Table 2).
• The painful arc pattern for acute facet strain is increased pain on extension, on lateral bending to the painful side, and on rotation to the opposite side (the motions that would increase loading on an ipsilateral facet joint).


TABLE 2 Painful Arcs in Acute Facet Syndrome

ORIGIN OF PAIN                         MOVEMENTS THAT CAUSE PAIN

Disc protrusion                                            Flexion
Muscle or ligament strain                             Flexion
                                                                   Lateral flexion
                                                                   Rotation to opposite side

Acute facet syndrome                                  Extension on lateral bending to same side
                                                                   Rotation to opposite side
 
• Acute facet syndrome is most common on the left side (probably because most people are righthanded).
• There is pain in the lumbosacral triangle.
• Pain extends into the left buttock and upper thigh.
• Gait is antalgic on the left with a list to the right side.
• Lordosis is reduced, and reversal is incomplete on attempted trunk flexion.
• Larson’s test is normal.
• The SLR test is limited to 60° on the right by localized lower back pain and 80° on the left by tight hamstrings.
• There is localized tenderness at the spinous process and in the adjacent left paravertebral muscle belly.
• Increased pain restricts spinal extension, left lateral flexion, and right rotation.
• Resolution is prompt with simple readily available measures.
• Specific pathologic confirmation is not available.

PHYSIATRIC INTERVENTIONS

• Gentle lumbar manipulation, which relieves pain, except for mild residual soreness
• Lumbar mobilization without an end-arc thrust
• Flexion exercise home program, twice daily
• Lumbar rotation mobilization technique home program
• Body mechanic and lifting technique instruction6

TENSION MYALGIA (FIBROSITIS)

• “Lesion” is unidentifiable by laboratory tests, electromyography, radiography, direct biopsy, or electroencephalography.
• This is a diagnosis of exclusion.
• Other names include fibromyositis, fibromyalgia, tension myositis, and muscle attachment syndrome.
• The pain spasm cycle can be initiated by continuing muscle contraction.
• The cycle may begin when psychological stress or anxiety results in muscle tension.
• Persistently increased muscle tension may cause diffuse muscle pain in the involved muscles and their attachments. This explains the increased tenderness seen in many of the classic trigger points.
• Increased tenderness and pain in these sites might be a result of a lowered pain threshold associated with psychological tension.
• Tension myalgia can be derived from muscular or psychological tension.
• Posture is poor.
• Sleep disorder may contribute to a lowered pain threshold and increased pain.

EXAM

• Generalized morning stiffness
• Improvement in pain after getting up and moving.
• Worsening pain as day progresses.
• Continuous, but light, sleep at night; waking tired and unrefreshed
• Temporary relief provided by heat and rest
• No radicular features
• Mildly increased lumbar lordosis
• No list
• Manual muscle testing, deep tendon reflexes, negative jolt test, and normal Larson’s test
• Spinal motions normal without painful arcs
• SLR test negative and limited to 70° bilaterally by tight hamstrings
• No true muscle spasms
• Multiple areas of increased tenderness in parascapular, paracervical, paralumbar, and gluteal trigger point sites
• Overreaction and regionalization in classic trigger point sites

PHYSIATRIC INTERVENTIONS

• The management strategy should break the pain–spasm cycle and reduce anxiety.
• Reassurance should be directed at answering questions to reduce anxiety.
• A thorough general and musculoskeletal exam should be conducted.
• Review normal and abnormal findings in detail.
• Tension myalgia should be discussed with the patient.
• Cryotherapy, local heat, and massage can be used for temporary pain relief and reduction of muscle tension.
• Trigger point massage, trigger point injections, and spray and stretch techniques also can be used.
• Temporary symptomatic relief is essential for achieving lasting results from learned relaxation techniques.

RELAXATION TECHNIQUES

• Relaxation techniques are designed to reduce resting muscle tension by conscious effort (general relaxation).
• Myoelectric biofeedback assists with this education process.
• Relaxation techniques improve the general level of fitness, body mechanics, and quality of sleep.

TRAUMATIC BACK STRAIN SYNDROME, SUPERIMPOSED GENERALIZED DECONDITIONING, AND SUPERIMPOSED PAIN AMPLIFICATION SYNDROME EXAM

• Chronic post-traumatic soft tissue back injury
• Nonorganic regionalization in pain localization and on muscle testing.
• Nonorganic tenderness over the sacrum and on gentlesuperficial skin rolling.
• SLR sitting distraction test is positive.
• Overreaction on tandem walking evaluation.
• Passive trunk rotation simulation maneuver is negative.
• A Waddell score of 3 or more associated with significant nonorganic behavior is an indication for further psychological investigations; however, it is possible that the patient is not malingering or faking the pain.

PHYSIATRIC INTERVENTIONS

• The terms pain amplification syndrome and symptom magnification syndrome may be preferable to older terms like function pain and chronic pain behavior.

• A diagnosis of deconditioning is appropriate if it is documented by objective dynamometric testing or supported by a functional capacity or work capacity evaluation.

• This deconditioning may play as large a role in limiting rehabilitation as do nonorganic and psychological factors.

• Family and employer support, psychological and vocational counseling, relaxation, training in good body mechanics, physical reconditioning, a workhardening program, and early settlement of litigation are all essential for return to a high-quality and productive life.

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