Acute Deep Deltoid Ligament Reconstruction using a Novel, Arthroscopically-Assisted Technique: Case Report

Abstract

Category: Arthroscopy; Ankle; Sports; Trauma Introduction/Purpose: The deltoid ligament complex is the main stabilizing structure of the ankle mortise and is often disrupted in rotational ankle injuries. Current treatment involves open techniques for the acute repair of the superficial deltoid layer, however, repair or reconstruction of the deep deltoid ligament (DDL) has proven to be challenging using open techniques. Our described arthroscopically-assisted technique allows for better intra-articular visualization and durable reconstruction of the ruptured DDL with suture and knotless bone anchors. The goal of this new, minimally invasive approach is to facilitate a faster and more reliable recovery and prevent long-term dysfunction and degeneration from medial and rotational ankle instability. We believe it has the potential to provide improved immediate ankle stability and decrease overall surgical morbidity compared to open treatments. Methods: Case of a 48-year-old male with ligamentous-equivalent Massioneuve fracture with medial clear space (MCS) measuring 11 millimeters. Arthroscopy revealed unstable syndesmosis and rupture of the DDL. After syndesmotic fixation, there was persistent MCS widening on stress exam. Arthroscopically-assisted DDL reconstruction was performed using an accessory anteromedial (AAM) portal between the tibialis anterior tendon and posterior tibial tendon. Needle localization identified the sagittal midpoint of the medial wall of the talus, inferior to articular cartilage. Anchor sites at both the medial talar wall and midportion of the distal medial malleolus (insertion and origin of the DDL, respectively) were then drilled via the AAM portal under arthroscopic and fluoroscopic guidance respectively at the isometric point. A suture anchor was placed into the talus and tails were loaded and secured to the medial malleolus with a bioabsorbable anchor. Ankle mortise was stable to stress exam and there were no restraints to physiologic motion. Results: The patient was kept non-weight bearing on his right lower extremity for a total of 6 weeks postoperatively and was seen in the clinic for routine follow-up visits at 2 weeks, 6 weeks, and 3 months post-procedure. Sutures were removed at 2 weeks, without any wound complications, and he was transitioned from splint to a short leg cast. He required only three days of oral narcotic analgesia. Weight-bearing in a controlled ankle motion (CAM) boot and physical therapy were both initiated at 6 weeks post-op. Radiographs at each follow-up visit were without abnormalities. At 3 months post-op, he was graduated from the CAM boot into a lace-up ankle brace, without any complaints of ankle pain or instability. The patient progressed well with full weight-bearing and physical therapy and was seen for a final visit at 5 months post-op with stable MCS. No complications were encountered. Conclusion: Acute DDL rupture is a common occurrence in ankle fractures and can be diagnosed radiographically and by arthroscopy. Known sequelae of untreated DDL disruption include medial instability and late valgus collapse. This case report demonstrates a novel, minimally invasive technique to successfully reconstruct the DDL, which may minimize the surgical morbidity compared to open dissection methods and allow for decreased recovery time postoperatively. This approach may also be utilized for cases of chronic instability. Future work includes larger case series with long-term follow-up and refinement of the technique as instrumentation advances.