Thompson Hemiarthroplasty for Femoral Neck Fracture Is Associated With Increased Risk of Dislocation

This contemporaneous large multicenter retrospective study reflective of current practice, assesses the impact of patient factors, prosthesis selection, and implant features on the risk of dislocation after hip hemiarthroplasty for femoral neck fracture.

Radiographic records for 4116 consecutive patients who underwent a hip hemiarthroplasty between January 1, 2009 and September 30, 2017 at 3 acute hospitals (including a regional major trauma center) for a neck of femur fracture were reviewed in conjunction with United Kingdom National Hip Fracture Database records.

In total, 4116 patients were eligible for inclusion in the study; 63 of 4116 (1.5%) dislocations were identified. Patient age, gender, preoperative abbreviated mental test score, postoperative abbreviated mental test score, and American Society of Anaesthesiologists grade were not found to be significant predictors of dislocation rates ( P < .05). The Furlong prosthesis was the most commonly used implant (2280/4116, 55.4%) followed by the Exeter V40 + Unitrax head (1179/4116, 28.6%), other implants used during the study period were the monoblock Austin-Moore and Thompson implants. Hemiarthroplasty operations undertaken with the Thompson (24/273, 3.7%) were found to have significantly higher dislocation rates ( P < .05). Cemented vs uncemented, variable vs fixed offset, and monoblock vs modular implant designs did not contribute to higher dislocation rates ( P < .05). Surgeon seniority was also not a significant risk factor for subsequent dislocation ( P < .05).

Thompson hip hemiarthroplasties are associated with higher dislocation rates when compared to a contemporaneous cohort of implant choices and considerations for their use should be made in conjunction with this major risk factor for the need for subsequent operations.