Percutaneous Inferior Extensor Retinaculum Augmentation Technique for Chronic Ankle Instability

Objective To specify indications and contraindications of the modified percutaneous inferior extensor retinaculum augmentation (PIERA) technique for chronic ankle instability cases, and to introduce technique details and report surgical outcomes and complications. Methods The PIERA technique was performed on seven patients with chronic ankle instability (four females and three males, 36.4 +/- 15.1 years of age, and course of symptoms of 33.7 +/- 8.8 months) from June to October 2018 in this retrospective study of case series. All patients demonstrated attenuated ligamentous tissue quality, which was confirmed using preoperative ankle MRI. IER were drew up to the distal fibula using suture anchors with the ankle in neutral position for all cases, to engage the entire IER in reconstructing the stability of the ankle. Patients were assessed using American Orthopaedic Foot and Ankle Society Ankle-Hindfoot (AOFAS) score and Cumberland Ankle Instability Tool (CAIT) scores pre- and postoperatively at the last follow-up examination. Preoperative and postoperative outcome scores of patients were compared using paired t-test. A p value of less than 0.05 was regarded statistically significant. Results Mean follow-up duration was 16.7 +/- 1.6 months. The mean AOFAS score significantly improved from 66.9 +/- 11.2 preoperatively to 93.7 +/- 8.5 postoperatively (P = 0.001). Mean CAIT score significantly improved from 13.1 +/- 4.7 preoperatively to 26.3 +/- 1.8 postoperatively (P = 0.001). Patients did not report any wound healing problem, numbness, swelling, or instability at the last follow-up examination, except for one patient who reported pain and minimal stiffness, and presented an AOFAS score of less than 80 and a CAIT score below 24. All patients returned to at least recreational sport activity level. Conclusion The PIERA technique can improve the functional outcomes of patients with chronic ankle instability with few complications.