Knee reconstruction with prosthesis and muscle flap after total arthrectomy

Area of Science:

• Orthopedic Surgery
• Surgical Oncology
• Reconstructive Surgery

Background:

• Bone sarcomas around the knee often require extensive surgical resection.
• Intraarticular involvement necessitates complex reconstruction strategies.
• Extracapsular en bloc excision is a common approach for knee bone sarcomas.

Purpose of the Study:

• To evaluate the efficacy of knee reconstruction using a massive prosthesis and medial gastrocnemius muscle transfer following en bloc excision for bone sarcoma.
• To assess the functional outcomes and complication rates of this reconstructive technique.

Main Methods:

• Nine patients with primary malignant bone tumors of the knee underwent extraarticular resection including the patella.
• Reconstruction involved implantation of a knee prosthesis and transfer of the medial gastrocnemius muscle and pes anserinus tendons to restore the extensor mechanism.
• Magnetic resonance imaging was used to assess intraarticular involvement preoperatively.

Main Results:

• All resections achieved negative margins with no local recurrences.
• Two patients developed metastases, and two experienced infection as the major complication.
• Mean Musculoskeletal Tumor Society score was 61%, mean flexion was 62 degrees, and mean extensor lag was 12 degrees.
• Functional outcomes were poorer in patients with proximal tibia resection, suggesting arthrodesis as an alternative.

Conclusions:

• Prosthesis and medial gastrocnemius muscle flap reconstruction offers acceptable function and cosmetic results for selected knee bone sarcoma patients.
• Careful patient selection is crucial for optimal outcomes.
• Arthrodesis may be a preferred option when the proximal tibia is resected with the knee joint.