Surgical Technique: Vastus Medialis and Vastus Lateralis as Flap Transfer for Knee Extensor Mechanism Deficiency

Abstract

Background Loss of the quadriceps tendon, patella, and patellar tendon leaves a major anterior defect that is difficult to close and compromises knee extension strength. Gastrocnemius muscle transfer does not sufficiently cover such major defects. This paper describes a new surgical technique that addresses these defects and the results of eight cases of revision TKA managed with this new technique. Description of TechniqueThe new procedure transfers the vastus medialis or the vastus lateralis and their tibial attachments or both muscles and their distal expansions combined with gastrocnemius and soleus flaps to cover major deficiencies in the anterior knee. Nine cadaver knee specimens were dissected to determine the effect of the transfer on nerve and blood supply of the muscles. Methods Eight patients underwent the new procedure between 2005 and 2009. Four knees had vastus medialis transfer, two vastus medialis and vastus lateralis transfer, two vastus medialis and medial gastrocnemius transfer, and two medial gastrocnemius and medial 1 .2 of the soleus muscle transfer. Minimum followup was 15 months (mean, 43 months; range, 15-74 months). Patients were evaluated for anterior knee pain, quality of knee closure, ROM, extensor lag, walking ability, use of assistive devices, and ability to climb stairs with the operated extremity.

Surgical Technique: Muscle Transfer Restores Extensor Function After Failed Patella-Patellar Tendon Allograft

“…revision TKA, deficiencies of the anterior capsule and skin are common [20], so repeat cadaver allograft is not a good solution. Likewise, Achilles tendon allograft [7] and substitution with polymer mesh has had some success in restoring patellar tendon deficiency [3], but these procedures are inadequate to fill the defect left by removal of the allograft material.…”

“…Furthermore, deficiency of anterior skin precludes the use of nonviable substitutes for the missing patella and tendons. Whereas gastrocnemius flaps can close deep soft tissue defects and protect synthetic mesh substitutes for the patellar tendon, they are not sufficient to close the proximal portion of the defect left when a failed quadriceps tendon-patellar-patellar tendon allograft is removed [20]. In cases of major deficiency of the quadriceps and patellar mechanism, transfer of the vastus medialis and vastus lateralis has been effective both to close the soft tissue gap and also to restore quadriceps function [20].…”

“…Whereas gastrocnemius flaps can close deep soft tissue defects and protect synthetic mesh substitutes for the patellar tendon, they are not sufficient to close the proximal portion of the defect left when a failed quadriceps tendon-patellar-patellar tendon allograft is removed [20]. In cases of major deficiency of the quadriceps and patellar mechanism, transfer of the vastus medialis and vastus lateralis has been effective both to close the soft tissue gap and also to restore quadriceps function [20]. Addition of the medial gastrocnemius muscle to achieve soft tissue closure of the distal portion of the knee also further improved quadriceps function [20].…”

“…In cases of major deficiency of the quadriceps and patellar mechanism, transfer of the vastus medialis and vastus lateralis has been effective both to close the soft tissue gap and also to restore quadriceps function [20]. Addition of the medial gastrocnemius muscle to achieve soft tissue closure of the distal portion of the knee also further improved quadriceps function [20]. Even in cases with major anterior tibial bone loss, soft tissue closure can be augmented with transfer of the medial soleus muscle [20].…”

“…Addition of the medial gastrocnemius muscle to achieve soft tissue closure of the distal portion of the knee also further improved quadriceps function [20]. Even in cases with major anterior tibial bone loss, soft tissue closure can be augmented with transfer of the medial soleus muscle [20]. This combination of medial and lateral vastus and gastrocnemius muscles (sometimes augmented with the soleus muscle) also can be done in the presence of anterior skin deficit [20].…”