CALAXO osteoconductive interference screw: the value of postmarket surveillance

The CALAXO osteoconductive interference screw was recalled in August 2007 due to reports of increased numbers of postoperative complications associated with screw swelling and prominence leading to the need for surgical debridement. This study reviews complications associated with CALAXO screw use in a consecutive cohort of patients undergoing anterior cruciate ligament reconstruction surgery by the senior author at the authors' institution. Over a 12-month period, 226 CALAXO interference screws, either of 20 mm length or 25 mm length, were implanted in 112 patients, and postoperative complications were noted. The 25-mm tibial screw was over 5 times (RR 5.2, 95% CI 1.8 to 15.3) more likely to be prominent than the 20-mm screw (p value=.002). Four surgical debridements were required in the 25-mm tibial screw group; none were required in the 20-mm group. The authors hypothesize that the inability to bury the longer screw length into the bone tunnel is associated with postoperative complications associated with the CALAXO screw.