Joint Preservation Surgery for Varus Ankle Arthritis with Large Talar Tilt.

Background: Varus ankle arthritis with large talar tilt (TT) is a challenging condition when considering joint preservation surgery. Three-dimensional deformity of the talus has been demonstrated with weightbearing computed tomography in varus ankle arthritis with large TT. The aim of this study was to investigate the clinical and radiographic results of posterior tibial tendon (PTT) transfer generally combined with bony realignment for varus ankle arthritis with large TT in nonparalytic ankle arthritis and to determine the indications for PTT transfer.
Methods: This study includes 23 ankles with varus arthritis and TT larger than 7.5 degrees. Patients were categorized into improved (19 ankles) and unimproved (4 ankles) groups according to the postoperative clinical results at the last follow-up. Clinical and radiographic results were compared between the groups. A cut-off point for preoperative TT that indicated a borderline between improved and unimproved groups was determined to suggest the appropriate indication for joint preservation surgery.
Results: In the improved group, TT, radiographic stage, Meary angle, and hindfoot alignment significantly improved at 6 months after surgery and were maintained at the last follow-up. In the unimproved group, the radiographic parameters mentioned above did not improve at 6 months after surgery, and TT decreased to 0.8 degrees as radiographic stage had progressed to end-stage arthritis at the last follow-up. In this small series, the cut-off point for predicting failure of surgery was 14.3 degrees of preoperative TT.
Conclusion: PTT transfer often combined with bony realignment procedures may be a reasonable option for treating painful varus ankle arthritis with TT less than 14 degrees and hindfoot varus.
Level of Evidence: Level IV, case series.