Safety of Anteromedial Portals in Elbow Arthroscopy: A Systematic Review of Cadaveric Studies

Abstract

To systematically review available literature comparing location and safety of 2 common anteromedial portals with nearby neurovascular structures in cadaveric models and to determine the correct positioning and preparation of the joint before elbow arthroscopy. The review was devised in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Inclusion criteria consisted of original, cadaveric studies performed by experienced surgeons on male or female elbows evaluating anteromedial portal placement with regard to proximity of the arthroscope to neurovascular structures. Exclusion criteria consisted of case reports, clinical series, non-English language studies, and noncadaveric studies. Statistical analysis was done to measure reviewer reliability after scoring of each study. During screening, 2,596 studies were identified, and 10 studies met final inclusion as original, cadaveric investigations of anteromedial portal proximity to neurovascular structures. The difference in distance between proximal and distal portals was <1mm for the brachial artery and <1.5mm for the medial antebrachial cutaneous nerve, whereas the ulnar nerve was 4.17mm further from the distal portal and the median nerve was 5.07mm further from the proximal portal. Joint distension increased the distances of neurovascular structures to portal sites, with the exception of the ulnar nerve in distal portals. Elbow flexion to 90° increased distances of all neurovascular structures to portal sites. The results show that the proximal anteromedial portal puts fewer structures at risk compared with the distal portal. Elbows in 90° flexion with joint distension carry a lower risk for neurovascular injury during portal placement. These findings suggest the proximal anteromedial portal to be the safer technique in anteromedial arthroscopy of the elbow. Discrepancies in placement of portals have existed in the literature, indicating differing safety margins regarding surrounding neurovascular anatomy. The present study aims to link together the literature-based evidence to describe the safest anteromedial portal variation.