Back Pain

Mr. Y is a 30-year-old man with low back pain that has lasted for 6 days.

Mr. Y felt well until 1 week ago, when he helped his girlfriend move into her third floor apartment. Although he felt fine while helping her, the next day he woke up with diffuse pain across his lower back and buttocks. He spent that day lying on the floor, with some improvement. Ibuprofen has helped somewhat. He feels better when he is in bed and had transiently worse pain after doing his usual weight lifting at the gym.

Mr. Y has no history of other illnesses. He has had no trauma, weight loss, fever, chills, or recent infections. He takes no medications and does not smoke, drink, or use injection drugs. The back pain does not radiate to his legs. On physical exam, he has mild tenderness across his lower back; lower extremity strength, sensation, and reflexes are normal. Straight leg raise test is negative.

You reassure Mr. Y that his pain will resolve within another 2–3 weeks. You recommend that he use ibuprofen as needed and be as active as possible within the limits of the pain. Rather than weight lifting, you suggest swimming or walking for exercise until his pain resolves. You also provide a handout on proper lifting techniques and back exercises, to be started after the pain resolves. He cancels a follow up appointment 1 month later, leaving a message that his pain is gone and he has resumed all of his usual activities.

S: Mr. Y is a 30 y/o man, with no significant past medical history, seeking treatment for complaint of low back pain that has lasted for 6 days. The diffuse pain across his lower back and buttocks started the day after he helped his girlfriend move into her apartment. It does not radiate to his legs. Inactivity and ibuprofen somewhat helped relieve the pain. Weightlifting worsens the pain. He denies recent trauma, weight loss, fever, chills, or recent infections.

O: Lower Back – Mild tenderness; Lower Extremity – strength, sensation, and reflexes are normal; Straight leg raise test – Negative

A: Mechanical Low Back Pain; R/O: Herniated Disk

P: Ibuprofen PRN (as needed); Recommended Physical Activity – no weight lifting until pain resolution, consider swimming/walking. Patient should be as active as possible as tolerated without experiencing pain; Counseling – Handout given on proper lifting techniques and back exercises, start when pain resolves; Follow-up in 1 month – if pain has not resolved, consider CT/MRI to R/O Herniated Disk.

Evaluation of patients with low back pain is primarily concerned with discerning between serious and nonspecificback pain. Serious back pain may be the result of systemic disease or pain with neurologic symptoms or signs, while nonspecific back pain is related to musculoskeletal structures. Nonspecific back pain associated with musculoskeletal structures is synonymous with mechanical back pain. Examples of Specific musculoskeletal back pain would include lumbar radiculopathy, spinal stenosis, or cauda equina syndrome. In these situations, the relationship between the anatomic deficits and the syndromes experienced is evident. In nonspecific back pain there is no such clear relationship.

Causes of serious back pain that are systemic in nature include neoplasia and infection. These cases are emergencies. On the other hand, there are several serious causes of back pain that are not emergencies (but do require treatment). These include osteoporotic compression fracture and inflammatory arthritis.

Causes of serious back pain that are related to visceral disease (require treatment) include retroperitoneal disease like aortic aneurysm and retroperitoneal adenopathy or mass. They also include pelvic disease like prostatitis, endometriosis, and pelvic inflammatory disease. They also include renal disease like nephrolithiasis, pyelonephritis, and perinephric abscess. They also include GI disease like pancreatitis, cholecystitis, and penetrating ulcer.

In formulating a differential diagnosis, all of these causes must be considered. It is important to couple the differential diagnosis with the history that the patient reports. Given Mr. Y’s history, nonspecific mechanical back pain is the most likely cause. Statistically, 97% of back pain seen in the primary care setting is of this kind. That is not to say, however, that a neurologic issue or systemic issue is not causing the back pain. For that reason, it is important for the history and physical exam to include components that rule out specific musculoskeletal causes of back pain and systemic disease as the cause of the back pain.

Mechanical Low Back Pain has several characteristics. The patient may also experience pain/stiffness in the buttocks or hips. It is usually the result of an exertion, and the pain improves when the patient is lying down on their back. 75% to 90% of patients improve within 1 month. 25-50% of patients report experiencing an additional episode over the next year. There are several risk factors for persistent low back pain including maladaptive pain coping behaviors, high level of baseline functional impairment, low general health status, and presence of psychiatric comorbidities.

Lack of red flags (symptoms related to systemic or neurologic disease or trauma) is 99% predictive of nonserious etiology of low back pain. Imaging studies may reveal anatomic abnormalities, like degenerative disks, even in asymptomatic patients. Data indicates that imaging does not improve clinical outcomes such as pain or functional status in patients with acute (<4 weeks) or subacute (4-12 weeks) pain.

NSAIDs, acetaminophen, and skeletal muscle relaxants are used in treating acute back pain. Use of heat and spinal manipulation has proven to help. Subacute or chronic low back pain is often treated with tricyclic antidepressants. These medications, coupled with cognitive-behavioral therapy, exercise, and spinal manipulation have proven valuable.