Arthroscopic Shelf Acetabuloplasty in the Treatment of Acetabular Dysplasia Combined With Cam-Type Femoroacetabular Impingement.

Acetabular dysplasia is a hip condition characterized by abnormal development of the acetabulum, which can be present from birth or develop during childhood and may persist into adulthood. Mild or borderline acetabular dysplasia frequently is associated with cam-type femoroacetabular impingement in adults. Over time, the association of impingement and abnormal contact can lead to hip pain, cartilage damage, labral tears, and an increased risk of developing hip osteoarthritis. Several surgical treatments have been proposed: arthroscopic capsular plication, periacetabular osteotomy, or shelf acetabuloplasty. As mini-invasive shelf acetabuloplasty procedure has already proven its effectiveness, an arthroscopic shelf acetabuloplasty represents a less-invasive, less-risky procedure and allows during the same procedure to perform intra-articular resection of the femoral cam, labrum repair and capsular plication. This Technical Note describes an original technique of arthroscopic shelf acetabuloplasty that combines an outside-in arthroscopic approach for the intra-articular procedure (labral repair, femoroplasty, capsular plication) and an endoscopic shelf acetabulopasty with a tricortical iliac crest autograft secure with a single cannulated screw.

Can Patella Instability After Total Knee Arthroplasty be Treated With Medial Patellofemoral Ligament Reconstruction?

Background: The aim of this study was to describe outcomes of patients who had undergone medial patellofemoral ligament reconstruction (MPFLr) to treat patellofemoral instability (PFI) following total knee arthroplasty (TKA). Material and methods: This is a retrospective case series of consecutive patients treated for PFI after TKA. Patients were included if they had radiographic documentation of patella dislocation or subluxation and component position was adequate. MPFLr was performed using a quadriceps tendon autograft. The graft was fixed with either an interference or additional suspensory fixation. A tibial tubercle osteotomy was performed in select indications. Patients were assessed with Kujala and International Knee Score (IKS) at a minimum 12-month follow-up and radiographically with plain radiographs. Results: A total of 22 patients (23 procedures) were included. The mean follow-up period was 38 months (range 12-72). Average preoperative femoral component rotation on computed tomography was 0.10° external rotation (range 3° internal rotation to 3° external rotation). All patients had improved clinical and radiographic outcomes postoperatively. At the last follow-up, the mean IKS knee score was 77.6 ± 13.1, mean IKS function score was 75.2 ± 23.3, and mean Kujala score was 60.2/100 ± 10.9. There was 1 mechanical failure, which occurred following MPFLr with interference fixation. There were 6 complications (28.1%) postoperatively. Patients receiving double fixation of the MPFLr graft had higher clinical and radiographic scores; however, this difference was not statistically significant. MPFLr had a patella-lowering effect, 0.97 preoperatively to 0.74 postoperatively (P = .069). Conclusion: MPFLr in appropriately selected patients is a satisfactory option to treat PFI following TKA.

Tibial tuberosity osteotomy and medial patellofemoral ligament reconstruction for patella dislocation following total knee arthroplasty: A double fixation technique.

INTRODUCTION: Patella instability post total knee arthroplasty (TKA) is a rare complication. Tibial tubercle osteotomy (TTO) with medial patellofemoral ligament reconstruction (MPFLr) has not been well described for this indication. This paper describes a surgical technique to address the unique challenges faced when performing TTO and MPFLr in the prosthetic knee. TECHNIQUE: This technique and video describe a TTO and MPFLr via an extensile incision and medial sub-vastus approach. A 6 cm long TTO is performed, if indicated, to medialise the extensor mechanism up to 1 cm and fixed with ×2 4.5 mm cortical screws. For the MPFLr, a quadriceps tendon autograft is utilized, with the natural insertion to the superior pole of the patella being left undisturbed. The graft is first attached with an interference screw and then reinforced with an endobutton to provide crucial cortical fixation to overcome the problem of low bone mineral density encountered in this area of the femur following TKA. RESULTS: Five patients underwent MPFLr using the described technique. No failures or recurrence of instability occurred at the last follow-up. Pre-operative mean patella tilt and shift were 44° and 3.5 cm, respectively. Post-operatively, mean tilt and shift were 4.1° and 0.4 cm, respectively. There was one wound dehiscence requiring surgical debridement and closure. CONCLUSION: This paper describes a surgical technique to perform a TTO and MPFLr for patella instability post-TKA. The described method highlights key adaptations to address the unique challenges in this patient population.