Return to Alta: Patellar Height Increases Over Time After Tibial Tubercle Osteotomy With Distalization

Area of Science:

• Orthopedic surgery
• Biomechanics
• Radiographic analysis

Background:

• Patellar instability with patella alta is often treated with tibial tubercle osteotomy with distalization (TTO-d).
• The long-term effects of TTO-d on maintaining postoperative patellar height are not well understood.
• This study investigates patellar height changes after TTO-d in skeletally mature patients.

Purpose of the Study:

• To assess changes in patellar height after TTO-d.
• To determine if patellar height returns to a state of alta post-TTO-d.
• Hypothesize a return to patella alta after surgical distalization.

Main Methods:

• Case series (Level of evidence, 4).
• Included skeletally mature patients with follow-up radiographs ≥3 months post-TTO-d.
• Calculated Caton-Deschamp (CD) and Blackburne-Peele (BP) indices preoperatively, immediately postoperatively, and at 3-month, 6-month, and ≥1-year follow-ups.

Main Results:

• 35 knees in 28 patients were analyzed, with 20 having ≥1-year follow-up.
• Preoperative CD and BP indices decreased significantly immediately post-TTO-d (P < .001).
• At ≥1-year follow-up, CD and BP indices increased significantly (P < .001), with 88% showing a transition to patella alta.

Conclusions:

• TTO-d resulted in progressive increases in patellar height indices over time.
• A return to patella alta was observed in most patients with long-term follow-up.
• Further research is needed to correlate radiographic findings with clinical outcomes.