991 - Resection of lumbar facet synovial cyst utilizing MILD procedure in patients with foot drop with resolution of symptoms. An possible alternative to lumbar decompression or synovial cyst rupture

Case Diagnosis: Foot drop related to synovial cyst impingement on traversing lumbar nerve root

Case Description: We present two cases both of which had foot drop related to synovial cyst impingement on traversing nerve root.   Both cases had symptoms for 3+ months, without response to physical therapy, or corticosteroid injection and medical management. In 1 case, patient was ready utilizing AFO at the time of consultation.

Traditionally, synovial cyst aspiration or synovial cyst pressurizing/rupture with or without epidural injection could be attempted and if not successful, patient would be referred to spine surgery for open laminectomy and decompression.

In these 2 cases, we use Minimally Invasive Lumbar Decompression (MILD procedure) was performed to decompress the nerve root by resection of synovial cyst and portion of the facet synovium leading to resolution of the foot drop.

Discussions: Synovial cyst may impinge on traversing nerve root and resulting pain, numbness, tingling or motor deficit.  Facet synovial cyst relates to osteoarthritis of the zygapophyseal joint.  When patient presents with pain, numbness, tingling and weakness in a nerve root pattern, MRI may demonstrate contribution of the synovial cyst into the impingement.  Traditionally, epidural injection, and synovial cyst rupture or aspiration is attempted prior to open laminectomy and decompression.  In our case report, we present to patient's, both with synovial cyst and foot drop, responded to minimally invasive lumbar decompression ( MILD procedure), done percutaneously with fluoroscopic guidance.  Both cases resulted in resolution of foot drop without need for major surgery.

Conclusions: Minimally invasive lumbar decompression procedure could be a viable alternative to laminectomy for treatment of radiculopathy, with or without foot drop related to synovial cyst impingement on traversing nerve root as long as the zygapophyseal synovial cyst is accessible with this percutaneous approach.  Procedure is done under conscious sedation without any general anesthesia in an ambulatory setting.