Sciatica is a condition that causes a sharp, burning pain in the back, buttock, and leg. The condition is caused by injury to or compression of the sciatic nerve, which is located in the back of the leg. This study will determine the effectiveness of the steroid prednisone in decreasing pain and improving function in people with sciatica.

Sciatica is most often caused by a herniated disc in the lumbar region of the back and results from inflammation of the nerve roots as they exit the spine. It is a very common cause of back and leg pain, loss of function, and inability to work. Although sciatica is common, the effectiveness of current treatments is limited. Epidural steroid injections (ESIs), which can reduce inflammation of the nerve roots, are commonly used to decrease sciatica pain and restore normal function in patients. The exact effectiveness of ESIs, however, is unknown. If inflammation, and not compression, is the main cause of sciatica, it is reasonable to consider giving the steroid orally rather than by injection. If oral steroids prove effective, patients and clinicians will have access to a simple, inexpensive therapy that can be prescribed by primary care physicians without delay. This study will determine the effectiveness of the oral steroid prednisone in decreasing pain and improving function in people with sciatica.

Participants in this study will attend a screening visit at which they will answer questions about their health to determine eligibility, undergo a neurologic exam, and have a plain lower spine x-ray. An MRI of the lower spine will be performed for those who meet clinical eligibility. Participants whose MRI shows that a disc has ruptured in a specific way will be randomly assigned to receive either a 15-day course of prednisone capsules or a 15-day course of placebo capsules. Participants will take their assigned study medications in addition to their usual pain medications.

At Week 3, participants will return for a follow-up visit during which they will answer questions about their pain and general health and wellness. Participants who are still having considerable pain will be offered an epidural steroid injection (ESI) as a part of the study. At Week 6, participants will be called at home for a telephone interview and again answer questions about their general health and wellness; this telephone call will last about 20 minutes. If they continue to have considerable pain, they will be offered a second ESI as part of the study.

At Week 12, an interviewer will phone participants to determine if their pain has decreased and whether they have been able to return to their normal activities. The telephone contact will last about 20 minutes. Additional information about their back problems will be obtained from their medical records and from Kaiser Permanente's computerized medical records on their use of health care and medicines for back problems. At Week 24, participants will attend an evaluation visit at the Spine Clinic to assess their progress and symptoms. At Week 52 (1 year from randomization), participants will undergo a final telephone interview.

Inclusion Criteria:

• Seeks care at a Kaiser Permanente clinic spine care specialist at the San Jose, Redwood City, or Roseville site
• Complains of low back pain and functionally incapacitating leg pain extending below the knee with a nerve root distribution
• Score of at least 20 on the modified Oswestry Disability Index
• Appears, in the opinion of the study physician, to be very likely to have a herniated lumbar disc
• MRI study confirms a herniated disc consistent with the signs and symptoms

Exclusion Criteria:

• Onset of sciatica symptoms occurred more than 3 months before study entry
• Cauda equina syndrome
• Active cancer
• Acute spinal fracture
• Currently taking oral steroids
• Diabetes mellitus and taking insulin or glycohemoglobin greater than 10%
• Systolic blood pressure greater than 180 mm Hg or diastolic blood pressure greater than 110 mm Hg
• Pregnant or breastfeeding
• Active peptic ulcer disease
• History of intolerance to steroid therapy
• Bleeding diathesis or anticoagulant therapy
• Ongoing litigation or workers compensation claim for low back pain or sciatica
• Underwent previous lumbar surgery
• Received epidural steroid injection (ESI) within the 12 months before study entry
• Unable to read or speak English
• Progressive or severe motor loss

Entire study period, up to 52 weeks