Renal osteodystrophy: Neurosurgical considerations and challenges

Background: Dialysis-associated destructive spondyloarthropathy (DSA) is the major bony complication of end-stage renal disease, most commonly found in the lower cervical region. The risk factors for developing dialysis-associated DSA include duration of hemodialysis and patient age. Patients with DSA have a higher incidence of osteoporosis and poor bone mineral density, which may place them at greater risk of atraumatic fractures, instrumentation failure, and neurologic compromise. Methods: We describe a case of cervical radiculopathy due to dialysis-associated DSA atraumatic vertebral body fractures with a postoperative course that was complicated by instrumentation failure. We reviewed the literature regarding all 138 published cases, presenting the complications, surgical treatment options, and outcomes. Results: A 44-year-old dialysis-dependent man presented with acute neck pain, radiculopathy, and weakness due to atraumatic fracture of C5 and C6 vertebral bodies. He underwent anterior C5 and C6 corpectomies, reconstruction with mesh cage and plate, and supplemental posterior instrumentation (C4-T1). Six weeks later, a computed tomography scan revealed anterior translation across the instrumented area with failure of the posterior instrumentation. He subsequently underwent traction, revision reinstrumentation from C2 to T5, and placement of external halo ring/jacket for 6 months. At 18 months later, he remains ambulatory without evidence of construct failure. Conclusions: Patients with renal osteodystrophy present a challenge for the spine surgeon due to compromised bone density. Hardware failure at the bone-construct interface is common in these patients, with revision surgery needed in 22% of published cases. Longer constructs with circumferential instrumentation and halo immobilization may minimize the risk of pseudoarthrosis and construct pull-out.