Low Back Pain

Low Back Pain

Work-up


Physical examination.

Standing. Examine for obvious defects. Palpate for tenderness or muscle spasm. Test the mobility of the lumbar spine with flexion, extension, and lateral flexion. Observe the patient's gait and have the patient walk on his toes (foot plantar flexion test S1) and up on his heels (foot dorsiflexion test L5).

With the patient sitting. Sitting straight-leg raising (SLR) test: passive extension of the knee. A positive test is radicular pain at less than 60 degrees. 'Crossover' pain with radicular symptoms in the leg not lifted is fairly specific for disk disease.

Reflexes. Patellar reflex tests the L4 root; Achilles tendon reflex tests the S1 root (L5-S1 disk). Babinski sign: if present, indicates disorder above the lumbar region such as cord tumor or CVA.

Sensation. L4: medial border of the feet; L5: triangular area at the base of middle toes on the dorsum of the feet; S1: lateral margin of the feet and distal portion of the calf.

Sensation. Check hip abduction (L5 motor), perianal sensation (S3-5: also controls anal and urethral sphincter tone), hip extension (L5 motor). Saddle anesthesia, decreased anal sphincter tone, and crossover leg pain are signs of a central disk herniation, which is considered a surgical emergency. Must be suspected if there is a history of new bowel or bladder incontinence.


Laboratory and imaging studies.

Lumbar spine films are not necessary in most patients. Plain films should be obtained if symptoms last more than 6 weeks, there is suspicion or history of malignancy, or the patient is using steroids, is over 50 years of age, has a history of trauma, or has neurologic deficits. There is no need to obtain radiographic evaluation for history consistent with muscle strain.
Patients suspected of having infectious or neoplastic causes of low back pain should have an imaging study such as a bone scan, CT, or MRI.
If severe symptoms persist for several weeks despite conservative therapy and disk herniation or another surgically correctable disorder is suspected, then CT or MRI imaging may be useful. Generally, since will not want to intervene surgically unless pain is present for at least 6 weeks, no need for these imaging studies unless there is some indication other than pain (that is, neurologic symptoms such as loss of bowel and bladder function). MRI and CT have replaced myelography except in rare circumstances.
Electromyogram and nerve conduction velocity. Can be used to evaluate suspected nerve root involvement.
Blood tests. Differential CBC with ESR, and biochemical screening (calcium phosphate, alkaline phosphatase) should be performed when a systemic cause for back pain is suspected.
Immunoelectrophoresis of serum and urine samples. Allows diagnosis of most cases of myeloma.



Treatment

Acute back pain (no longer than 6 weeks).
There is no difference in outcome when patients with acute back pain are treated by a family physician, a chiropractor, or an orthopedic surgeon. Therapy by a family physician is the most cost effective.
Regardless of the method of treatment, 40% better within 1 week, 60% to 85% in 3 weeks, and 90% in 2 months. Negative prognostic factors include more than 3 episodes of back pain, gradual onset of symptoms, and prolonged absence from work.
Bed rest. Should be kept to a minimum, and early mobilization encouraged. If symptoms recur or considerable pain develops in relation to a specific activity or level of activity, the patient should temporarily limit activity for several days but should not cease all activity.
Analgesia. NSAIDs most commonly used. Provide pain relief and decrease inflammation. Acetaminophen provides analgesia but has no anti-inflammatory properties. May be used with or instead of NSAIDs. Narcotics should be used for short term only for severe pain. Muscle relaxants such as cyclobenzaprine 10 mg PO TID or QID work mostly by sedating patients and preventing activity. However, they probably have little effect on muscle spasm.
Physical therapy. Although classically several modes have been used to hasten resolution of back pain, most physical therapy modes have no effect when rigorously tested. Traction, local application of heat, cold, and ultrasound, and corsets have been shown to have no effect. Transcutaneous nerve stimulation may provide short-term symptomatic relief but have no proved long-term benefit.
Epidural steroid injections. May speed recovery from radicular pain.
Rehabilitation exercises. Trunk extensors, abdominal muscles, aerobic conditioning. Main benefit is that they promote early mobilization, which is critical in treating acute back pain. The specific exercise doesn't matter as much as the mobilization.

Chronic back pain. Once back pain has been established for more than 1 year, the prognosis is poor. Mild analgesia should be used, avoidance of chronic or repeated reliance on narcotics for pain control is a key management priority. If depression is encountered, it should be treated.

Indications for admission and referral. Cauda equina syndrome (urinary retention, sphincter incontinence, saddle anesthesia), severe neurologic deficits (footdrop, gastrocnemius-soleus or quadriceps weakness), progressive neurologic deficit, or multiple nerve root involvement.

A 67-year-old white male retired factory worker was found to have an abdominal aortic aneurysm on routine physical examination. A vascular surgeon has recommended operative repair. The patient is a former smoker, with a 10-pack-year smoking history. Three years ago, while under the stress of a forced retirement, he had angina which responded well to sublingual nitroglycerin. He has had no angina for 1 year.

Which one of the following conditions would be the most likely cause of perioperative death in this patient?



a.Pulmonary complications
b.Peripheral embolization
c.Operative site infection
d.Myocardial infarction
e.Cerebral infarction

D

Myocardial infarction is the major cause of perioperative death in patients undergoing surgery for abdominal aortic aneurysm. This is especially true of patients with a history of known coronary artery disease or with EKG abnormalities, and it is true even if the coronary artery disease is stable.
Cerebral infarction occurs infrequently, even though cerebral vascular disease is commonly present in this patient group. Operative site infection, peripheral embolization, and pulmonary complications are all significant postoperative complications which may cause death, but they are less frequent causes of death than myocardial infarction.

A patient falls on his outstretched hand and complains of pain in the wrist. There is tenderness to palpation over the anatomic 'snuff box,' but multiple radiographs of the wrist are negative.

The most appropriate treatment would be to

a.place in a thumb spica cast for 3-4 months
b.place in a short-arm cast for 6-8 weeks
c.place in a long-arm cast for 4-6 weeks
d.immobilize with a plaster cast and obtain additional radiographs in 2 weeks

D

Since scaphoid fractures may not be evident on radiographs for 10 days to 2 weeks, sprains with tenderness over the scaphoid should be immobilized in a splint or cast for 2 weeks and then re-examined by x-ray. If a fracture is demonstrated, a thumb spica cast should be placed on the limb for 2-5 months, depending on which portion of the scaphoid is injured.

The mother of a newborn female who has bilateral cleft lip and palate refuses to nurse her and asks the nurses to feed her in the nursery rather than in her room.

Of the following, the MOST likely explanation for this response is

A. denial that the condition exists
B. fears over the baby's appearance
C. feelings of anger
D. feelings of guilt
E. mourning the loss of a normal child

A or C

A 56-year-old white male has cirrhosis which has progressed as he has ignored your advice to stop drinking. You hospitalize him for treatment of gastrointestinal bleeding. Gastroscopy shows the bleeding to be due to gastritis rather than to an ulcer or varices. His bleeding is stopped, plasma volume is restored with packed red cells, and he does not develop delirium tremens. You administer spironolactone (Aldactone), and over the course of a week in the hospital he loses approximately 10 kg of ascitic fluid.

He is scheduled to be discharged tomorrow morning, but he suddenly develops abdominal pain and a temperature of 38.9 C (102.0 F), and becomes delirious. When you examine him, you find a blood pressure of 90/60 mm Hg, hypoactive bowel sounds, and a diffusely tender abdomen with nonlocalized rebound tenderness. An abdominal tap reveals cloudy ascitic fluid with a large number of polymorphonuclear leukocytes.

The most likely cause of this sudden change in his condition is



a.spontaneous bacterial peritonitis
b.spontaneous pneumoperitoneum
c.a perforated diverticulum
d.a perforated gastric ulcer
e.acute pancreatitis

A

Spontaneous bacterial peritonitis is an increasingly frequent complication of cirrhosis and other conditions which cause ascites. This patient has a classic clinical presentation, with abdominal pain, fever, rebound tenderness, hypoactive bowel sounds, hypotension, and cloudy ascitic fluid. All of these findings are not invariably seen with this condition, however.
Spontaneous bacterial peritonitis occurs in alcoholic cirrhosis, other types of liver disease, occasionally in biliary cirrhosis and cardiac cirrhosis, alcoholic hepatitis, and acute viral hepatitis. It is common in disseminated lupus and can occur in children with nephrotic ascites. Multiple organisms may be involved. The great majority of cases occur in hospitalized patients, and at least 80% of patients have been hospitalized more than a week.
Diverticulitis, appendicitis, and a perforated gastric ulcer are much less likely to produce the generalized abdominal tenderness with rebound seen in peritonitis. Pancreatitis tends to be a presenting complaint rather than a complication developing in a hospitalized patient. Spontaneous pneumoperitoneum is not a frequent complication in patients without extensive diverticulitis.

A 60-year-old white male has had intermittent posterior nuchal headaches for many years. Which one of the following is most likely to help establish a diagnosis?



a.An MRI scan of the head
b.A CT scan of the head
c.An erythrocyte sedimentation rate
d.A neurologic examination
e.A thorough history

E

The best information for making the diagnosis in the patient presented is most likely to come from a thorough history focusing on provocation, quality, region, strength, and timing of the headaches, as well as associated symptoms, a medication history, and screening for depression. CT and MRI scans have not been proven helpful if focal clues are not found. Laboratory tests are not generally helpful when used randomly. While a complete neurologic examination should be done, the results are usually normal in patients with chronic headaches

A 25-year-old white male complains of the recent onset of rapidly progressing periodontitis. As part of your evaluation, which one of the following tests would be most advisable?

a. Serum lead
b. Serum ferritin
c. Serum B12
d. HIV titer

D

Rapidly progressive periodontitis appears to be an early sign of immunocompromise in patients with HIV infection. HIV antibody titers and T4:T8 lymphocyte ratios are indicated, especially if the patient's dental hygiene appears adequate. Dental referral is also indicated. None of the other tests mentioned is associated with periodontitis.

A 29-year-old white female is hospitalized following a right middle cerebral artery stroke confirmed on an MRI scan. Her past medical history is remarkable only for a history of an uncomplicated tonsillectomy during childhood, and a second-trimester miscarriage 3 years ago. The only remarkable finding on physical examination is left hemiplegia.

The initial laboratory workup reveals normal hematocrit and hemoglobin levels, a normal prothrombin time, and a platelet count of 200,000/mm3 (N 140,000-440,000). The active partial thromboplastin time is 95 sec (N 23.6-34.6), and it does not normalize when the patient's serum is mixed with normal plasma. A serum VDRL is positive, and a serum FTA-ABS is nonreactive.

Which one of the following is the most likely diagnosis?



a. Protein C deficiency
b. Thrombotic thrombocytopenic purpura
c. Antiphospholipid syndrome
d. Neurosyphilis
e. Hemophilia

C

The antiphospholipid syndrome occurs because of the appearance of a heterogeneous group of circulating antibodies to negatively charged phospholipids, including most commonly a lupus anticoagulant and anticardiolipin antibodies. The antibodies are usually detected by a false-positive serologic test for syphilis. Clinical features include venous and arterial thrombosis, fetal wastage, thrombocytopenia, and the presence of an activated partial thromboplastin time inhibitor. It is an important diagnostic consideration in all patients with unexplained thrombosis or cerebral infarction, particularly in young patients.
Although hemophilia would also be associated with a prolonged activated partial thromboplastin time (aPTT), the PTT would normalize when the patient's serum was mixed with normal plasma. Neurosyphilis is excluded by the negative serum FTA-ABS result. Thrombotic thrombocytopenic purpura is not associated with prolongation of the aPTT and is associated with a hemolytic anemia. Although protein C deficiency is a hypercoagulable state that can lead to stroke, none of the laboratory abnormalities suggests this diagnosis.