Spinal metallosis: a systematic review

Purpose To document a rarely reported complication associated with spinal instrumentation and to evaluate the current literature on spinal metallosis and spinal metalloma. Methods A local case report is presented. EBSCOhost, PubMed and ScienceDirect databases were used to conduct a systematic review for articles describing spinal metallosis and spinal metalloma. Results A total of 836 articles were identified using the terms "metalloma" or "metallosis". Exclusion of arthroplasty-related abstracts retrieved 46 articles of which 3 full text articles presenting spinal metalloma as a causative pathological finding responsible for neurological signs and symptoms in patients with previous spinal fusion instrumentation were reviewed. Our case is the first described with titanium-composed posterior instrumentation and fifth reported, demonstrating the phenomena of neurological symptoms and signs attributed directly to neural tissue compression by spinal metalloma after spinal instrumentation. Conclusion Spinal metallosis can present weeks to years after spinal instrumentation surgery and is a potential cause of neural compression. This process appears to be independent of the instrument composition as metallosis has now been demonstrated in both titanium and stainless steel constructs.