Inside-out method to develop volar arthroscopic portals of the wrist in cadaver specimens

Three direct volar portals for wrist arthroscopy have been described previously: two radiocarpal and one midcarpal. The aim of this study was to systematically describe four volar arthroscopic portals through minimally invasive incisions using an inside-out approach from known dorsal portals. Four volar arthroscopic wrist portals were studied on six hand specimens using an inside-out technique: a radial radiocarpal approach (RRCA), an ulnar radiocarpal approach (URCA), a radial midcarpal approach (RMCA) and an ulnar midcarpal approach (UMCA). Each volar approach corresponded to a dorsal approach: the 3/4 portal for RRCA, 4/5 portal for URCA, dorsal radial midcarpal approach for RMCA, and dorsal ulnar midcarpal approach for UMCA. The average range of motion of the scope through the RRCA was 65° in radial deviation and 72° in ulnar deviation; through the URCA it was 62° in radial deviation and 64° in ulnar deviation; through the RMCA it was 62° in radial deviation and 60° in ulnar deviation, and through the UMCA it was 59° in radial deviation and 68° in radial deviation. No iatrogenic injuries to important anatomical structures were noted. Based on these results, it is possible to perform these four volar portals through an inside-out technique with incisions mirroring the dorsal portals. They were easy to perform, safe and should be useful in ligament or bony intracarpal repair indications.