Medical Student Michigan State University College of Human Medicine Troy, Michigan, United States
Introduction: Postoperative C5 Palsy (C5P) is a well-known delayed complication of cervical spine surgery that classically presents as new or worsened postoperative shoulder abduction weakness with or without elbow flexion involvement and may also be accompanied by sensory deficits in the C5 dermatome. Importantly, there is no current standardization in the definition of C5P, as the condition has been previously defined using a variety of clinical parameters. Our primary objective was to describe how C5P and its recovery are defined in the existing literature.
Methods: In accordance with PRISMA guidelines, a systematic PubMed search was conducted using the keywords “C5 Palsy” and “Recovery”. Articles that included a definition of postoperative C5P and/or recovery were included. Studies where C5P occurred independent of spine surgery or where subjects underwent cervical spine surgery for an indication other than degenerative changes were excluded.
Results: Our initial search yielded 272 articles, of which 41 met our final inclusion criteria. Postoperative C5P was most commonly defined (by 19 of 41 included studies) as a reduction in deltoid muscle strength by at least 1 grade using manual muscle testing (MMT), although other less common definitions utilized a MMT grade of ≤3 or included sensory deficits. Recovery of C5P was most commonly defined as achieving a grade of 5 on MMT, while less than 100% improvement on MMT was considered partial recovery.
Conclusion : In the existing literature, there is a clear discrepancy in C5P definitions, which has ultimately led to a large spectrum of phenotypes and severities being labeled as C5P. Given that treatment options and prognosis can vary for C5P, it is essential that C5P be properly measured and classified. We hope that this systematic review will build the foundation for such an effort.
