In the treatment of CLAI, the Broström-Gould procedure has demonstrated favorable surgical outcomes and has been widely adopted by scholars. Gould emphasized that suturing the ligament tissue of the anterior inferior part of the lateral malleolus to its anterior edge can effectively enhance lateral stability in ankle joint. However, Gould did not specify the exact location for reinforcing suture placement[15]. Most documented methods currently involve direct pulling of the lateral portion of IER to anchor it onto the periosteum of lateral malleolus[21–23]. Nevertheless, our experimental findings indicate that IER, particularly its lateral bundle, is highly resilient and challenging to elongate. Additionally, we observed a robust connection between IER and lateral malleolus through tough deep fascia tissue; furthermore, fibrous tissue density increases as it approaches IER. Dalmau [24–25] noted that successful implementation of Gould's procedure relies on an "X" type retinaculum being present and ensures desired ankle stability after repair. In Abu's study, 5 (14) specimens exhibited an X-shaped structure of the IER. However, Abu[26] emphasized that the IER was formed by thickening of the deep dorsal fascia of the ankle. Our study did not observe an "X" shape in the lateral bundle of IER, which may be attributed to specimen quality; nevertheless, this finding suggests that there is relatively dense fascial fiber connection between the lateral bundle of IER and the insertion point of the ATFL. In our study, we applied vascular forceps to tension and stretch the lateral bundle of IER to its maximum capacity. We believe that regardless of whether the shape of IER is "X" or "Y", as long as we sutured a wide area of deep fascia to connect with the lateral bundle effectively, we can achieve optimal tension.
In our study, we observed a narrow space between the deep fascia and the joint capsule in front of the lateral malleolus, with minimal fat tissue separating them. Consequently, distinguishing between these two layers of tissue structure becomes challenging. As a result, during the minimally invasive Gould procedure, it is common practice to suture together the ankle capsule and the deep fascia (specifically, the outer superior oblique bundle of IER) to the anterior edge of the lateral malleolus. Our study compared this combined stretch with that of solely stretching the deep fascia and found that the former exhibited greater tension. Therefore, we conclude that reinforcing sutures involving both joint capsule and IER can achieve maximum tension during minimally invasive Gould procedures.
In this study, we measured that the line connecting the shortest distance from the insertion of the ATFL to the IER was at an angle of approximately 60° with respect to the long axis of the fibula. In minimally invasive Gould procedure, it is recommended to maintain a suture angle of around 60° in order to facilitate drawing more fibrous tissue with enhanced texture. The shortest distance from the insertion point of the ligament to the IER was found to be 12.5 ± 0.6mm. Therefore, if the length of suture needle exceeds this distance, it would enable effective pulling together of dense fibers within IER and enhance overall suture strength.
In cases of chronic lateral ankle instability with a prolonged duration of injury, we observed that the ATFL stump exhibited flocculation and significant tendon body contracture during arthroscopic or open surgery, rendering direct suturing of the ligament unfeasible. Consequently, it was often necessary to suture the joint capsule and ligament stump to the insertion site on the lateral malleolus during the procedure, resulting in favorable treatment outcomes. Feng[27] reported that there was no statistically significant difference in postoperative outcomes between ATFL stump repair and nonrepair when the all-arthroscopic Brostrom-Gould procedure was used to treat CLAI. In our study, we observed challenges in distinguishing the ankle capsule from the ATFL completely, as a considerable portion of them overlapped with each other. Additionally, we noted that the normal ATFL exhibited significant tension in its anatomical state, requiring substantial stretching to restore it to its original position after artificial cutting at the insertion point. Therefore, during the minimally invasive Broström procedure, we effectively sutured the capsule together with the disrupted end of the ligament to its insertion site. It is possible that the capsule plays a more crucial role in this process, which has been supported by previous reports[28–29].
When performing minimally invasive Broström-Gould procedure, the crucial consideration lies in avoiding injury to the superficial peroneal nerve. The reported incidence of this complication ranges from 4.54–13.3% in clinical practice[30–31], which may be attributed to factors such as the positioning of the arthroscopic anterolateral approach, the angle of the Gould procedure, and the distance covered by the suture needle. Jorge[32] introduced the concept of a "safe zone" and demonstrated that operating within this zone during arthroscopic Broström technique for lateral ankle stabilization ensures no damage is inflicted upon both the superficial peroneal nerve and tendon. The needle entry angle and suture distance indicated in this study also fall within the range defined by this "safe zone."
The minimally invasive arthroscopic Broström-Gould procedure is increasingly favored by ankle surgeons due to its aesthetic advantages, reduced trauma, and simplified operation. Moorthy[33–35] pointed out that compared to traditional open repair, arthroscopic repair yields similar clinical outcomes with a lower incidence of wound complications. In cases involving unfamiliar anatomical structures, improper suture techniques under the microscope may have no impact on mild injuries, low BMI or exercise requirements; however, it can increase the risk of failure in severe injuries, high BMI or exercise requirements[36]. Precise suture surgery can maximize reinforcement of the ATFL and IER while achieving favorable results across different patient populations.