Nondiscogenic Sciatica: What Clinical Examination and Imaging Can Tell Us?

Area of Science:

• Neurology
• Orthopedics
• Radiology

Background:

• Sciatica often presents with pain mimicking lumbar radiculopathy.
• Approximately 10% of sciatica cases stem from nondiscogenic sources.
• Accurate diagnosis of nondiscogenic sciatica (NDS) is crucial for appropriate management.

Purpose of the Study:

• To present a series of 6 patients with infragluteal NDS.
• To highlight clinical and imaging features suggestive of NDS.
• To discuss the differential diagnosis of sciatica.

Main Methods:

• Retrospective study of 6 patients treated for NDS between 2010 and 2018.
• Analysis of clinical presentations, neurological examinations, and imaging findings.
• Review of diagnostic and therapeutic pathways.

Main Results:

• All patients exhibited sciatic pain, deep infragluteal tenderness, and a positive Tinel's sign related to the sciatic nerve (SN).
• Six distinct causes of NDS were identified: extrauterine endometriosis, rectal adenocarcinoma metastasis, low-grade sarcoma, schwannoma, high-grade sarcoma, and myxoma.
• Treatment varied, including surgery, pharmacological therapy, biopsy, and radiotherapy.

Conclusions:

• Differentiating discogenic from NDS can be challenging.
• Key indicators for NDS include sciatic pain with specific physical exam findings (Tinel's sign, deep palpation tenderness) and incongruent lumbar spine imaging.
• Patients with suspected NDS should undergo pelvic and gluteal magnetic resonance imaging.