Deltoid release in varus ankle deformity: Radiographic and clinical outcomes following total ankle arthroplasty.

BACKGROUND

While deltoid ligament release is commonly performed during total ankle arthroplasty (TAA) to assist with correction of varus deformity, its quantitative contribution and durability remain insufficiently defined.

PURPOSE: To evaluate the effectiveness and short-term stability of deltoid ligament release in correcting end-stage ankle arthritis with varus deformity during total ankle arthroplasty.

STUDY

DESIGN

Retrospective cohort study.

METHODS

A retrospective review was conducted on 496 patients who underwent TAA by five surgeons between January 2010 and December 2019, with a minimum one-year follow-up. Patients with varus deformity localized to the ankle joint were included and those with neutral or valgus alignment or prior rearfoot fusion were excluded. Immediate postoperative correction and maintenance of coronal alignment were compared between patients with and without deltoid ligament release using two-sample t-tests and difference-in-differences analyses.

RESULTS

Forty-five patients met inclusion criteria, with a mean follow-up of 4.52 ± 2.00 years. Thirteen patients (28.9%) underwent deltoid ligament release and thirty-two patients (71.1%) did not. The deltoid release group demonstrated greater preoperative deformity (14.88° vs. 10.70°, p = 0.040) and achieved a significantly larger mean correction (12.81° vs. 7.86°, p < 0.001). Difference-in-differences analysis showed an additional mean correction of -4.95° (95% CI: -9.03° to -0.87°). Postoperative alignment was similar between groups (2.07° vs. 2.84°, p = 0.403), with no significant coronal alignment changes between one- and two-year follow-up (p > 0.100).

CONCLUSION

Deltoid ligament release is an effective adjunct for achieving and maintaining neutral coronal alignment in severe varus ankle deformities undergoing TAA without rearfoot fusion.