# Reconstruction of the Knee Extensor Mechanism Using a Semitendinosus Tendon Graft and a Free Vascularized Latissimus Dorsi Musculocutaneous Flap for Complete Extensor Mechanism Loss With an Extensive Soft Tissue Defect: A Case Report

**Authors:** Kenichi Otoshi, Soichi Ejiri, Hironori Numazaki

PMC · DOI: 10.7759/cureus.102337 · Cureus · 2026-01-26

## TL;DR

A 58-year-old man with a severe knee injury was successfully treated with tendon graft and muscle flap surgery, allowing him to return to work.

## Contribution

This case report presents a novel combined approach using semitendinosus tendon graft and latissimus dorsi flap for knee extensor mechanism reconstruction.

## Key findings

- The patient returned to work six months post-surgery with minimal difficulty.
- Quadriceps strength remained below 30% of the contralateral side two years post-surgery.
- Recovery of hamstring muscle strength was sufficient.

## Abstract

A 58-year-old male sustained an injury that resulted in complete loss of the knee extensor mechanism, with an extensive soft tissue defect on the anterior aspect of the knee. Reconstruction of the knee extensor mechanism using an autologous semitendinosus tendon graft and coverage of the soft tissue defect using a free vascularized latissimus dorsi musculocutaneous flap were performed. The patient returned to his previous work six months after surgery without difficulty, except for a slight feeling of exhaustion when going up and down stairs. Recovery of hamstring muscle strength was sufficient, whereas quadriceps muscle strength remained less than 30% compared with the contralateral side even two years after surgery.

## Full-text entities

- **Diseases:** infection (MESH:D007239), knee extensor disruption (MESH:D007718), patella, patellar tendon, and quadriceps tendon defects (MESH:D052256), extensor mechanism disruption (MESH:D041781), Necrotic (MESH:D009336), dysfunction (MESH:D006331), quadriceps disruption (MESH:D019958), loss (MESH:D016388), skin necrosis (MESH:D012871), patellar defect (MESH:D031222), dysfunction of the knee extensor mechanism (MESH:D000092443), damage (MESH:D020263), knee pain (MESH:D046788)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Full text

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## Figures

5 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12935474/full.md

## References

15 references — full list in the complete paper: https://tomesphere.com/paper/PMC12935474/full.md

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Source: https://tomesphere.com/paper/PMC12935474