Male and female patients from 15 to 65 years old, with complaints of ankle giving away for the last 6 months, and clinical findings of lateral and medial instability were included. Individuals needed to undergo a minimum of 6 months of nonoperative treatment to qualify for surgery.
Existence of previous surgery, autoimmune diseases, neuropathy, inflammatory disease, isolated medial instability, progressive collapsing foot deformity, previous ankle infiltration, radiographic findings of ankle arthritis, cavovarus deformity, coagulopathies, a body mass index higher than 35, and site infection were exclusion criteria. Associated injuries, such as osteochondral lesions, syndesmosis instability, tendon ruptures, and fractures also excluded subjects from this research.
From March 2018 until January 2020, a total of 29 patients (30 ankles) were operated with MAI diagnosis. The mean participant age was 38.0 (SD 12.1), 48% were male (14/29), and women comprised 52% (15/29). Follow-up average was 14.8 (SD 6.9) (Appendix).
Lateral ankle instability was defined as the existence of giving-away symptoms associated with both maneuvers, anterolateral drawer and varus stress.   Medial instability in this multidirectional scenario was established by the presence of at least 1 of the clinical or arthroscopic findings below: anteromedial drawer or ankle valgus stress in the preoperative clinical assessment; an open book lesion at the medial malleolus, the ability to insert a 5-mm probe in the medial corner of the ankle, or the ability to insert a 5-mm probe at the medial clear space (between the medial surface of the talar body and the articular surface of the medial malleolus) in the arthroscopic evaluation.   
Physical examination for multidirectional instability was performed with the patient sitting with both limbs hanging, physician seated in front. Anteromedial drawer was executed by holding the lateral distal leg with one hand while the other embraced the medial calcaneus and talar region (index finger at the posterior tuberosity, thumb at the talar neck), producing an anterior movement combined with external rotation. Stress valgus was performed with one hand stabilizing the lateral distal leg while the other embraced only the calcaneus (thenar area at the calcaneus medial region, hypothenar area at the calcaneus lateral region), producing a valgus/eversion moment to the hindfoot. Any subjective asymmetry among ankles (millimeters for the drawer, degrees for the stress) determined the respective maneuver as positive.
For the arthroscopic diagnosis, an "open-book" lesion at the medial malleolus, as described by Vega et al,   was considered an indication of multidirectional instability. This finding corresponds to the proximal detachment of the superficial deltoid ligament (tibionavicular band) and explains the rotational component of this instability.   Besides, introduction of a 5-mm probe through the medial ankle corner or across the medial tibiotalar space were also considered signs of medial involvement in a multidirectional instability.   These assessments were performed by inserting the probe from the anteromedial portal whereas the visualization was carried from the anterolateral portal.
Previous nonoperative treatment consisted of at least 6 months of regular physical therapy focusing on global stretching, calf/intrinsics muscle strengthening, and balance training. Surgery was indicated if baseline symptoms persisted and was carried out by 4 fellowship-trained orthopedic foot and ankle surgeons, 2 with more than 20 years and 2 with less than 10 years of experience in the area.
After anesthesia and operative site preparation, traditional anterolateral (AL) and anteromedial (AM) arthroscopic portals were performed. A 4.5-mm (70-degree) scope was used to clean the joint and assess possible associated injuries. Necessary adjuvant procedures were executed before the ligament repair (Appendix). AL and AM impacts were resected when needed. Lateral and medial instability were confirmed arthroscopically, and ligament repairs performed starting laterally. A traditional arthroscopic Brostrom was performed, using an anchor and suture passers as previously described.   Sutures were passed but not tightened (Figure 1).
A medial anchor was inserted at the medial malleolus, in the quadrant described by Vega et al   (Figure 2). Sutures were passed respecting the safe zone illustrated by Acevedo et al.   The ankle was positioned in neutral (no posterior drawer) and the lateral sutures tightened with arthroscopic knots. Finally, the medial repair was finalized by tightening the deltoid sutures with the ankle still in neutral position (Figure 3).
Portals were closed and a dressing applied. Patients were put in a walker boot and remained nonweightbearing for 1 week. By the end of this first week, patients were evaluated, and progressive weightbearing began. The boot was worn until the fourth week, when it was replaced by a rigid ankle brace. This orthosis was used until the sixth week and then progressively removed (used for sports until the fifth month).
Physical therapy was started at the second postoperative week (no inversion, eversion, or rotation until the sixth week) and patients were allowed to return to practice (or baseline activities) in a light manner after 3 months. Full return to competitive activity was allowed by the fifth postoperative month (Figure 4).
Patients were assessed primarily for function through the American Orthopaedic Foot & Ankle Society (AOFAS) Hindfoot Score. Secondary outcomes included pain using the visual analog scale (VAS) and complications. Assessments occurred preoperatively (by 1 week before intervention) and at the 5-month postoperative follow-up.   
Complications were recorded as dehiscence, neural damage, infection, and rerupture. Dehiscence was defined as inability to heal the skin by the fourth postoperative week. Peripheral nerve damage was defined as hypoesthesia or paresthesia not resolved by the end of the sixth month after the surgery. Infection was defined as clinical signs of infection or pus drainage of the wound requiring the use of antibiotics. Rerupture was classified as an ankle sprain during the follow-up.
After collecting the information, we characterized the variable normality of the qualitative variables through the Kolmogorov-Smirnov test. For relationship between qualitative variables analysis, the Two Proportion Equality Test and the Spearman Correlation were used. Comparison among times of the study was performed with the Wilcoxon test.