439 - Left foot drop from Osteomyelitis related vertebral osseous destruction

Case Diagnosis: Left foot drop from Osteomyelitis related vertebral osseous destruction.

Case Description: 73 year old gentleman presented to physiatry clinic with persistent left lower limb weakness and foot drop after extended hospitalization for L2-L3 discitis/osteomyelitis and left psoas abscess thought to be precipitated by infected dental crown. Patient was treated with parenteral antibiotics and aspiration of the psoas abscess. No neurosurgical intervention was recommended. Repeat Lumbar Spine MRI revealed sequelae of chronic osteomyelitis at L2-L3 with endplate irregularity, but improved edema, with underlying multifactorial central canal narrowing at L2-3. Examination showed left ankle dorsiflexion trace/5, great toe extension trace/5, with intact ankle inversion and eversion( 4+/5, 5/5), ankle plantarflexion 5/5. On ambulation, hip hiking and compensation for dorsiflexion weakness was noted. Electrodiagnostic evaluation was ordered to confirm etiology of dense foot drop given incongruent lumbar spine MRI findings.

Discussions: EMG/NCS showed acute on chronic left sided lumbosacral polyradiculopathy with active denervation potentials throughout the L2 through L5 myotomes, and involving the lumbar paraspinals. There was no definitive evidence of a peroneal mononeuropathy at the fibular head despite the pattern of weakness seen on physical examination. The findings were determined most likely related to osseous destruction from osteomyelitis. Given active denervation, the patient was referred to neurosurgery and infectious disease for further consultation. After confirming no surgical or further antibiotic management would be pursued, the patient was ultimately prescribed a simple posterior leaf spring ankle foot orthosis set to neutral in conjunction with physical therapy.

Conclusions: This case highlights the role of the physiatrist within a multidisciplinary context; performing electrodiagnostics to confirm etiology of weakness in a complex patient, facilitating medical and surgical evaluations, and finally, providing a means for functional improvement with orthotic management.