Combined quadriceps lengthening (using an external ring fixator) and patellar tendon reconstruction (using a tendoachilles allograft) in a case of chronic patellar tendon rupture: A case report

Background: Patellar tendon rupture is an infrequent and debilitating condition, which if left untreated, is complicated by quadriceps contracture and patella alta. This results in reduced function of the knee extensor mechanism including extension lag, reduced range of motion (ROM), chronic knee pain, and frequent falls. Early primary repair has good results in most cases and is performed by opposing and suturing the tendon ends. However, when there is a delay between rupture and repair or in case of a re-rupture, primary repair techniques may not work due to retraction of the extensor mechanism. Several treatment modalities have been proposed in such cases, but there is no clear consensus. Methodology: We present the case of a 39-year-old male with chronic rupture of patellar tendon that was reconstructed with a two-stage technique. In the first stage, a ring-fixator was applied to stretch the quadriceps muscle and the second stage consisted of reconstruction of the patellar tendon with a tendoachilles allograft. This procedure was performed in two stages five weeks apart and almost four years after the initial injury. Results: Results were excellent at three years' follow-up with the patient achieving full extension, a ROM of 0-110 degrees and 85% quadriceps strength. There was significant improvement in his pain, mobility and quadriceps bulk. Conclusion: To our knowledge, this treatment has not previously been described in the literature. We present this case as a proven treatment option for treatment of chronic patellar tendon injuries with extensor mechanism shortening. (C) 2019 Elsevier B.V. All rights reserved.