Intraoperative Comparison of Measured Resection and Gap Balancing Using a Force Sensor: A Prospective, Randomized Controlled Trial.

BACKGROUND: For establishing femoral component position, gap-balancing (GB) and measured resection (MR) techniques were compared using a force sensor. METHODS: Ninety-one patients were randomized to undergo primary total knee arthroplasty using either MR (n = 43) or GB (n = 48) technique using a single total knee arthroplasty design. GB was performed with an instrumented tensioner. Force sensor data were obtained before the final implantation. RESULTS: GB resulted in greater range of femoral component rotation vs MR (1.5° ± 2.9° vs 3.1° ± 0.5°, P < .05) and posterior condylar cut thickness medially (10.2 ± 2.0 mm vs 9.0 ± 1.3 mm) and laterally (8.5 ± 1.9 mm vs 6.4 ± 1.0 mm). Force sensor data showed a decreased intercompartmental force difference at full flexion in GB (.8 ± 2.3 vs 2.0 ± 3.3u, 1u ≈ 15 N, P < .05). CONCLUSION: GB resulted in a greater range of femoral component rotation and thicker posterior condylar cuts resulting in an increased flexion space relative to MR. Intercompartmental force difference trended toward a more uniform distribution between full extension and full flexion in the GB vs MR group.

Recent advances in the management of liposarcoma.

Liposarcoma is the most common soft tissue sarcoma. With its various subtypes, the natural history of this disease can vary significantly from a locally recurrent tumor to a highly malignant one carrying a poor prognosis. Progress in the understanding of the specific molecular abnormalities in liposarcoma provides greater opportunity for new treatment modalities. Although surgical resection and radiation therapy remain the keystones for the management of primary liposarcoma, the inclusion of novel agents that target known abnormalities in advanced liposarcoma enhances the potential for improved outcomes.