Arthroscopic Deltoid Ligament Repair

Abstract

Category: Arthroscopy Introduction/Purpose: Background: Recent studies have underscored the importance of open repair of the deltoid ligament for rotational ankle instability in purely ligamentous injuries as well as with ankle fractures. With the advent of successfull arthroscopic lateral ligament techniques the authors have explored the use of similar arthroscopic techniques for deltoid repair. This study aimed to describe a novel arthroscopic technique for deltoid ligament repair and relate the proximity of anatomic structures at risk. Purpose: To evaluate the proximity of anatomic structures for a novel arthroscopic deltoid ligament stabilization technique and to define ideal landmarks and “safe zones” for this repair. Methods: Methods: Five human cadaveric ankle specimens were screened for the study. All specimens underwent arthroscopic deltoid ligament repair with a suture passer and suture anchor technique. Five cadaveric specimens were dissected to determine the proximity of anatomic structures after repair. Several distances were measured, including those of different anatomic structures to the suture knot to determine the “safe zones.” Measurements were obtained and statistical analysis was performed. Results: Results: None of the specimens revealed entrapment of the suture knots to the posterior tibial tendon (PTT) or saphenous nerve. The safe zone between the PTT and saphenous vein was a mean of 20 mm (range, 16-25 mm). On average, a 16 mm (range, 12-20 mm) safe distance was maintained from the suture knot to the PTT. The saphenous vein was in close proximity to the suture knot at a mean distance of 3 mm (range, 0-9 mm). Conclusion: The results indicate that there is a relatively wide safe zone between the PTT and the saphenous vein when performing the arthroscopic deltoid ligament stabilization technique. While none of the critical anatomic structures (except for saphenous vein) were entrapped by the suture knot, it was evident that the variable course of the saphenous vein renders it at risk for entrapment. This study further defines the proximity of adjacent anatomic structures and establishes the anatomic safe zones for the arthroscopic deltoid ankle stabilization procedure. By defining this relatively risk-free zone, surgeons less experienced with arthroscopic ligament repair techniques may approach arthroscopic suture passage with more confidence.