Patellar dislocation after total knee Arthroplasty: Stabilization technique using medial flap and suture anchors

Patellar dislocation following total knee arthroplasty (TKA) is an uncommon but functionally significant complication. Its management requires careful evaluation of prosthetic alignment, patellofemoral mechanics, and soft tissue integrity. The aim of this study was to describe a surgical stabilization technique using a medial retinacular flap fixed to the patella with suture anchors, combined with controlled lateral retinacular release, and to analyze its clinical and functional outcomes.

We conducted a retrospective case series between 2011 and 2023 in two specialized orthopedic centers. Fourteen patients with patellar dislocation after primary TKA-without prosthetic loosening or significant malrotation-were included. Clinical evaluation included pain (VAS), function (Lysholm score), satisfaction (Likert scale), and return to daily activities. Mean follow-up was 8.3 years.

All patients achieved a functional range of motion (≥0°-100°) without recurrence or instability. Lysholm scores improved significantly from 46.4 ± 3.05 to 83.8 ± 5.85 (p < 0.0001), and VAS pain scores decreased from 6.0 ± 0.71 to 1.2 ± 0.84 (p = 0.0012). No infections, hematomas, or reoperations were recorded. Overall satisfaction was high, with 85.7 % of patients reporting being satisfied or very satisfied.

The medial flap technique with suture anchor fixation is effective, reproducible, and low in morbidity. It represents a safe and less invasive alternative for the treatment of patellar dislocation following TKA in patients without mechanical failure.

IV. Case series.