Deltoid Ligament Injuries Associated With Ankle Fractures

Arguments For and Against Direct Repair

Jesse F. Doty, MD; Burton D. Dunlap, MD; Vinod K. Panchbhavi, MD, FACS; Michael J. Gardner, MD


J Am Acad Orthop Surg. 2021;29(8):e388-e395. 

In This Article

Argument Favoring Repair of the Deltoid Ligament

Although some studies suggest satisfactory results when the deltoid ligament was not directly repaired, the outcomes reported have been suboptimal in up to 30% of patients. Details given on the severity of the residual pain and deformity are lacking in many reports.[16,18,19] In Johnson and Hill's[7] 1988 publication, more than 60% of patients had residual tenderness of the medial ankle and 38% of patients had persistent medial instability over a year later. For this reason, many surgeons have given further consideration to deltoid ligament repair at the time of ankle fracture fixation. Many reports existed that describe implant selection and successful techniques for direct repair. Surgical repair of the deltoid ligament complex using suture anchors has shown good-to-excellent results in more than 90% of patients and fair results in 8% of patients.[22] Direct repair decreases the incidence of MCS widening. In addition, MCS and clinical outcome scores are inversely related. Patients with greater than 4 mm of residual MCS after ankle fracture fixation were shown to have decreased American Orthopaedic Foot and Ankle Society (AOFAS) scores.[23] Repairing the deltoid can restore the static and dynamic radiographic parameters without contributing to overall stiffness.[24]

Recent literature has used validated scoring systems to assess repair outcomes, whereas nonvalidated systems were reported in the counter argument. Yu et al published a 2015 multicenter study outlining success with deltoid ligament repair. A total of 1,533 surgical ankle fractures existed, of which 131 underwent deltoid ligament repair after fibula fracture fixation. The deltoid ligament was deemed surgical after fibula fracture fixation if medial ankle instability was evident on stress view, or if MCS was greater than 4 mm total, or greater than 1 mm compared with the superior joint space. Ninety-six of 131 repairs had undergone preoperative MRI, and 82 of the 96 MRIs (85%) demonstrated complete ligament rupture. Postoperative stress radiographs did not reveal any instability or post-traumatic arthritis at an average of 27-month follow-up. Notable improvements were seen after repair in all AOFAS, Visual analogue scale pain scores, and Short Form-36 scores. No control group existed for comparison.[25]

Woo et al reported that without direct repair some patients reported of persistent pain and swelling at the medial ankle ligamentous complex, although they had radiographic evidence of anatomic fracture healing. These patients described concomitant medial ankle instability associated with the sensation of giving way. During the study, the authors changed their protocol and started directly repairing the deltoid ligament complex, and then subsequently compared both groups. At the 17-month follow-up, the MCS was notably smaller when the deltoid ligament was repaired (P < 0.01). The outcome measures, including the AOFAS Ankle-Hindfoot score, visual analog pain scale, and the Foot Function Index, were similar between the two groups (P > 0.05). In the subset of patients who underwent syndesmotic fixation, a notably smaller MCS existed at the final radiographic evaluation, and all clinical outcomes were notably better when the deltoid ligament was repaired (P < 0.05). Linear regression analysis revealed that the final follow-up radiographic MCS ntoably affected clinical outcomes (P < 0.05).[26]

Repairing the ligament can decrease the MCS leading to improved outcomes but doing so may also preclude complications associated with allowing the ligament to heal indirectly. Evidence exists that neglecting the damaged tissue can lead to medial calcification and degenerative ankle arthritis.[27] Zhao et al reviewed 74 patients with unstable fibula fractures and deltoid ligament injury indicated by MCS >6 mm. Twenty patients were treated with open reduction of the lateral malleolus and deltoid repair using suture anchors, and the remaining 54 patients were treated with fracture fixation only. Mean follow-up was 53.7 months (range, 14 to 97). In an analysis of patients with Weber C fractures, the repair group showed better radiographic reduction when compared with the nonrepair group (P = 0.03). No complications were reported in the repair group, and all complications of malreduction (11/54) and revision surgery were in the nonrepair group. The authors concluded that surgical repair of the deltoid ligament is helpful in decreasing subsequent MCS widening and malreduction, particularly for the Weber C ankle fractures. One limitation of the study was lack of protocol when determining which patients to repair.[28]

Perhaps one of the most important patient cohorts in which direct repair should be supported are high-level athletes. The deltoid complex may retract distally and cause impingement in the medial gutter in unstable ankle fractures. In a review of NFL players, 14 underwent ankle fracture fixation with open deltoid ligament repair. All players underwent arthroscopy and débridement, followed by fibula fracture fixation with a plate and screws, syndesmotic fixation with a suture-button device, and open deltoid ligament repair with suture anchors. All were able to return to running and cutting maneuvers by 6 months postsurgery. The authors reported no notable differences in players' performance before surgery versus after surgery. Successful return to play in a full regular season NFL game was seen in 86% of the athletes after surgery. The two players who did not achieve return to play were medically cleared to do so, yet were released from their teams for unrelated reasons. No intraoperative or postoperative complications existed, and no clinical evidence existed of medial pain or instability, defined by clinical evaluation and radiographic examination. The primary limitation to this study was the lack of a control group to draw comparison.[29]

Similarly, all patients desiring to maintain an active lifestyle may have poorer outcomes without direct repair. In one study without medial-sided repairs, the results were promising in that all patients returned to work. However, on further review, only 75% of the patients who enjoyed active sports were able to return to those activities.[30] In these active patient cohorts, the importance of the deltoid ligament's contribution to rotational stability cannot be ignored. Typically, the talus undergoes slight internal rotation on ankle plantarflexion.[31] The injured ankle exhibits notable alterations in coronal and axial plane rotation if the medial soft-tissue restraints are not restored. Biomechanical cadaveric testing has demonstrated that repairing the deltoid can eliminate these abnormal talar translational movements and restore rotational stability.[32]

Dabash done a meta-analysis of 5 separate studies (which have been mentioned individually) with a total of 281 patients, 137 undergoing open reduction and internal fixation with deltoid ligament repair and 144 undergoing open reduction and internal fixation without ligament repair. The authors suggested that no clear indications existed to repair the deltoid ligament. However, it should be noted that some of the studies included in the analysis suggested that advantages existed to repair in certain subsets of patients, especially those with high fibular fractures (Weber C) or those with concomitant syndesmotic injury.[28,33] A notably lower rate of complications existed in the repair group compared with the nonrepair group. This was mostly because of a higher malreduction rate in the nonrepair group. Some authors suggest that avoiding a separate incision on the medial side of the ankle might protect against soft-tissue damage and infection, yet no increased incidence existed of such complications reported.[33]