A review of role of osteotomy in knee ligament injuries.

Realignment osteotomies around the knee joint are used primarily for management of arthritis. Traditionally, an unstable knee has been considered a contraindication for osteotomy. But with a better understanding of biomechanics of osteotomies and their effect on ligament instabilities, the beneficial role of osteotomies in managing an unstable knee is becoming clearer. This review looks at recent literature on this subject to help in formulating a management plan especially in failed ligament reconstruction patients.

Biomechanical comparison of graft structures in anterior cruciate ligament reconstruction.

PURPOSE: Double-bundle (DB) anterior cruciate ligament (ACL) reconstruction may offer kinematic restoration superior to anatomic single bundle (SB), but it remains technically challenging. The femoral attachment site has the most effect on ACL graft isometry, so a simplified three-socket (3S) construct which still uses two sockets to cover the femoral ACL attachment is attractive. It was hypothesised that ACL reconstruction using three- and four-socket techniques would more closely restore native knee kinematics compared to anatomic two-socket (SB) surgery. METHODS: Nine cadaveric knees were used to evaluate the kinematics of ACL-intact, ACL-deficient, anatomic SB, three-socket, and DB arthroscopic ACL reconstructions. Suspensory fixation was used, and grafts were tensioned to match the anterior draw of the intact knee at 20°. A six-degree-of-freedom robotic system measured knee laxity under 90 N anterior tibial force and rotational laxity under 5 N-m torque. Combined moments were applied to simulate the pivot-shift subluxation: 4 N-m internal rotation and 8 N-m valgus. RESULTS: Significant differences between reconstructions were not found during anterior tibial loading, apart from SB being more lax than DB at 60° flexion. All reconstructions produced comparable laxity to the intact state, apart from SB at 60°. Significant differences between reconstructions were not found at any flexion angle during tibial internal/external applied torques. Under combined loading, DB produced significantly less laxity than SB constructs apart from anterior tibial translation at 0° and internal rotation at 45°. 3S and DB were comparable to the native knee throughout. CONCLUSION: Although 3S restored laxities to a similar extent to DB, significant superiority over SB surgery was not observed. Although statistically significant differences were found between SB and DB surgery during anterior tibial and simulated pivot-shift loading, both remained similar to the native knee. The clinical relevance is that this study did not support an ACL graft construct more complex than an anatomic single bundle.

Baked beans in the knee? An odd-looking synovial swelling in the knee joint.

Lipoma arborescens (LA) is a rare benign neoplasm affecting large synovial joints, most commonly seen in the knee joint. Unlike other common swellings around the knee joint, LA is intra-articular and can lead to degenerative changes in the knee joint due to mechanical impingement. The importance of correct diagnosis with characteristic MR and macroscopic appearance and appropriate surgical treatment is outlined in this case report.

Unipolar versus bipolar uncemented hemiarthroplasty for elderly patients with displaced intracapsular femoral neck fractures.

PURPOSE: To compare outcomes of unipolar versus bipolar uncemented hemiarthroplasty and determine factors affecting outcomes. METHODS: 433 and 274 elderly patients with displaced intracapsular femoral neck fractures underwent uncemented unipolar hemiarthroplasty and uncemented bipolar hydroxyapatite-coated hemiarthroplasty, respectively. Surgical options were based on the patient's general condition and preinjury mobility status. In the respective groups, the mortality of 377 and 242 patients and the mobility of 270 and 217 patients were reviewed at the 4-month follow-up. Patient age, sex, American Society of Anesthesiologists [ASA] score, mobility, and mortality of the 2 groups were compared. RESULTS: Patients who underwent unipolar hemiarthroplasty were significantly older, less fit, and less mobile (p<0.001). Patients who underwent bipolar hemiarthroplasty achieved better outcomes for mortality and mobility (p<0.001). Among patients who were able to walk unaided before injury, more of those having bipolar hemiarthroplasty were able to do so at month 4 than those having unipolar hemiarthroplasty (13% vs. 33%, p<0.001). Mortality within 4 months was associated with age, male gender, and ASA score. When patients were stratified according to age groups, mortality within 4 months was lower in patients having bipolar hemiarthroplasty. CONCLUSION: In elderly patients with femoral neck fractures who were fit and physiologically young, uncemented bipolar hemiarthroplasty seemed to achieve better functional outcome.