Patella tendon length after patella arthroplasty



The study aimed to assess tendon length change following patello-femoral replacement (PFR) surgery and total knee replacement (TKR).


A retrospective analysis was conducted of 40 patients undergoing PFR surgery and 40 patients undergoing TKR and an unoperated control group. Immediate preoperative radiographs were compared with those at 1 year postoperatively. Intra/inter-observer error was assessed in four observers.


In the unoperated patients the mean shortening was 0.6% (range 6% shortening to 3% lengthening). The mean shortening after PFR surgery was 0.1% of shortening (range 14% shortening to 11% lengthening). The mean shortening after TKR was 7.14% (range 25% shortening to 7% lengthening).


Shortening of the patella tendon after PFR surgery occurs infrequently and less severely compared with TKR.

Level of evidence

Level 2 prognostic study.

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The study was reviewed and approved by the National Research Ethics Committee queries service.

Conflict of interest

The authors declare that they have no conflict of interest.

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Correspondence to Damian Clark.

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Clark, D., Mandalia, V., Hughes, A. et al. Patella tendon length after patella arthroplasty. Arch Orthop Trauma Surg 132, 179–183 (2012).

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  • Knee
  • Arthroplasty
  • Patella tendon shortening