Arthritis progression after patellofemoral joint replacement

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiology

Background:

• Patellofemoral joint replacement (PFJR) is an option for specific knee osteoarthritis cases.
• Progressive tibiofemoral osteoarthritis (OA) can necessitate revision surgery after PFJR.
• Understanding failure modes is crucial for optimizing PFJR outcomes.

Purpose of the Study:

• To quantify the incidence of tibiofemoral OA progression after PFJR.
• To identify risk factors for developing tibiofemoral OA post-PFJR.
• To evaluate the suitability of PFJR for patients with trochlear dysplasia.

Main Methods:

• Prospective study of 103 patients undergoing PFJR.
• Mean follow-up of 7.1 years.
• Radiographic assessment of tibiofemoral OA progression and measurement of preoperative sulcus angles for trochlear dysplasia.

Main Results:

• 14% of knees required revision, with 12% due to tibiofemoral OA.
• Radiographic tibiofemoral OA progression occurred in 7% of medial compartments over a mean of 51 months.
• Revision for tibiofemoral OA was significantly less common in patients with preoperative trochlear dysplasia (0% revised) compared to those without (17% revised).

Conclusions:

• Progressive tibiofemoral OA is a significant cause of failure after PFJR.
• Preoperative trochlear dysplasia is associated with a lower risk of developing tibiofemoral OA post-PFJR.
• Patients with patellofemoral arthritis secondary to trochlear dysplasia are ideal candidates for PFJR.