Microvascular flaps and collateral ligament reconstructions for soft tissue sarcomas at the knee joint

We report the suitability of free flap reconstruction in defects around the knee joint caused by soft tissue sarcoma (STS) excisions. The importance of collateral ligament reconstruction is also evaluated.Between years 1993 and 2005, 15 STS patients having a STS at the knee area with the need for free flap were treated in Helsinki University Hospital. Eleven musculocutaneous latissimus dorsi, 3 fasciocutaneous anterolateral thigh flaps, and 1 osteomusculocutaneous latissimus dorsi were used. The reconstruction of collateral ligaments was performed for 7 patients, 4 medial and 3 lateral; 6 with bone-tendon-bone grafts from patellar tendon and 1 with pes anserinus tendon transposition.There was no postoperative mortality. One flap was lost. Five patients needed debridement for minor wound complications. The mean follow-up time was 64 months. There were no local recurrences. Distant metastasis developed after the operation in 5 patients. Of these, 2 patients with solitary soft tissue metastasis were operated, and they are disease free. At 5 years 79% were disease-free. One patient with medial collateral reconstruction had recurrent patellar displacement and needed further operations; another with lateral collateral ligament and posterior capsular excision, that was not reconstructed, had lateral instability of the knee and needed orthosis.Free flap for STS of the knee is a reliable method. Patients can be operated with wider marginals and prognosis is good. Ligament reconstruction can be performed simultaneously, if collateral ligaments are excised.