Type C periprosthetic fractures treated with locking plate fixation with a mean follow up of 2.5 years

SummaryBackgroundType C periprosthetic femoral fractures present fixation problems related to the extent of the fracture and the quality of the bone stock.ObjectivesThe authors report a continuous and prospective series of type C periprosthetic femoral fractures to assess the mechanical stability of the femoral implant and the clinical outcome at the medium term.Material and methodsBetween April 2004 and November 2006, we treated 17 patients (15 females, two males) presenting a prosthetic hip fracture (12 cases), between the hip prosthesis and the knee (one case), and with a knee prosthesis (four cases). All the implants had no sign of loosening at the time of fracture. The patients’ mean age was 76.7 years (range, 39–93 years). Internal fixation was obtained with a locking compression plate (LCP) Synthes™ bridging the implant in place to prevent a weak zone. The rehabilitation protocol consisted in full weightbearing as much as possible.ResultsThe mean follow-up of the series was 31.5 months (range, 4–51 months). Four deaths were recorded during the follow-up. Minimally invasive surgery was performed in 15 patients. Total loading was possible immediately in 10 patients, partial loading at 20 kg in three patients, and no loading was possible until 6 weeks in four patients. Two infections and a bending-type mechanical complication of the plate secondary to a fall were observed. Consolidation was obtained in all cases with the appearance of callus formation beginning in the 6th week.DiscussionThe technique used allies the principle of closed internal fixation (with preservation of the fracture hematoma) with mechanical stability. The screws locking to the plate warrant an internal fixator with increased stability that is sufficient for early loading with no risk of losing the secondary axis. Despite this increased rigidity, we did not observe any particular stress on the femoral implants. We recommend bridging the implant and spaced locking for better distribution of the stresses during loading. This hardware, with, if possible, insertion using a reduced approach, seems adapted to periprosthetic femoral fractures, particularly in the elderly.Level of evidenceLevel IV, prospective therapeutic study.