From the Guidelines
S1 impingement can cause sciatica, as the S1 nerve root is a major component of the sciatic nerve. Sciatica refers to pain that radiates along the path of the sciatic nerve, which runs from the lower back through the hips and buttocks and down each leg. When the S1 nerve root becomes compressed or irritated (impinged), it can produce sciatic symptoms including sharp, burning pain, numbness, tingling, and weakness that travels from the lower back down the posterior thigh and sometimes into the foot.
Common Causes of S1 Impingement
- Herniated discs
- Spinal stenosis
- Degenerative disc disease
- Piriformis syndrome
Diagnosis and Treatment
Treatment typically involves a combination of pain management (including medications like NSAIDs, muscle relaxants, or in some cases gabapentin or pregabalin), physical therapy focusing on core strengthening and flexibility, and activity modification. For severe cases that don't respond to conservative treatment, epidural steroid injections or surgery might be considered. Proper diagnosis through physical examination and imaging studies like MRI is essential to confirm S1 impingement as the cause of sciatic symptoms, as noted in the guidelines from the American College of Physicians and the American Pain Society 1.
Key Points for Clinicians
- Provide patients with evidence-based information on low back pain with regard to their expected course, advise patients to remain active, and provide information about effective self-care options.
- Consider the clinical correlation between symptoms and radiographic findings, severity of symptoms, patient preferences, surgical risks, and costs when making treatment decisions.
- Be aware that findings on MRI or CT are often nonspecific, and decisions should be based on the clinical correlation between symptoms and radiographic findings.
From the Research
S1 Nerve Root Impingement and Sciatica
- S1 nerve root impingement can cause sciatica, as the S1 nerve root is one of the main causes of sciatica 2.
- Sciatica is a condition characterized by radicular pain in the distribution of the sciatic nerve, resulting from herniation of one or more lumbar intervertebral discs 3.
- The S1 nerve root can be affected by various conditions, including degenerative lumbar spines, herniated nucleus pulposus, and traumatic lumbosacral dislocations 2, 3, 4.
Mechanisms of Nerve Root Injury
- Nucleus pulposus and/or chronic compression can induce spinal nerve root injury, with inflammation playing a major role in the pathophysiologic mechanisms 5.
- Non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac may reduce nucleus pulposus-induced spinal nerve root injury, while others like ketoprofen may not have a significant effect 5.
- Cerebrospinal fluid proteins can be used as diagnostic parameters of nerve root compression, especially when surgery is a consideration or in patients in whom sciatica is unlikely 6.
Clinical Implications
- Epidural-perineural injection into the anterolateral epidural space can be an effective treatment for sciatica, especially in the L5/S1 segment where the S1 nerve root is located 2.
- Surgical treatment may be necessary for reduction, stabilization, and interbody fusion in cases of traumatic lumbosacral spondylolisthesis 4.
- Accurate diagnosis and treatment of nerve root compression are crucial to prevent long-term neurological deficits and improve patient outcomes 3, 4, 6.