Neglected percutaneous rod extrusion following posterior occipitocervical instrumentation: a case report

Abstract
Purpose: The extrusion of implant material is a rare complication but has been reported in several cases following anterior cervical spine surgery. A posterior spontaneous percutaneous rod extrusion after rigid occipitocervical (OC) instrumentation (screw and rod construct) has not been reported yet. The authors discuss potential complications after cervical spine surgery and its clinical management. Methods: This is a case report of a 56-year-old patient after posterior OC spine surgery with initially unobserved implant failure and posterior percutaneous rod extrusion. The implant failure with a missing rod has been documented 4 years later during a routine follow-up visit. Results: At the four-year follow-up, the asymptomatic patient presented with a stable occipitocervical junction and an improved range of motion after generalized sepsis with an epidural spinal abscess, decompression and posterior OC instrumentation. A computed tomography scan of the implant failure of a broken rod was noticed two years postoperatively. The patient failed to return to the clinic. For years postoperatively he returned to the clinic and the broken rod could not be detectable in-situ on the X-rays anymore. Conclusion: The posterior percutaneous rod extrusion following an OC instrumentation not noticed by the patient, is a very rare complication that has not been described in the literature yet. Once seen back in the clinic, the patient unexpectedly reported an improved ROM without neck pain. Usually, revision surgery or implant removal is recommended if an implant failure is documented.