Hip Revision Arthroplasty of Periprosthetic Fractures Vancouver B2 and B3 with a Modular Revision Stem: Short-Term Results and Review of Literature

Background Periprosthetic fractures Vancouver type B2/B3 after total hip arthroplasty (THA) is a challenging entity with increasing numbers. Limited data are available for this type of fracture treated with modular stems. Therefore, this study evaluated the outcome of Vancouver type B2/B3 fractures treated with a modular hip revision stem using a subproximal/distal anchorage and compared it to the current literature. Materials and Methods A consecutive series of periprosthetic Vancouver type B2/B3 fractures treated with a modular revision stem was retrospectively (2013 – 2016) evaluated. Assessment included the clinical (HHS, pain, ROM) as well as the radiological outcome (subsidence, loosening, facture healing). In adddition, the surgical technique is described in detail and results are compared with the current literature. Results A total of 18 patients (female/male 12/6) with Vancouver B2/B3 (n = 12/6) fractures with a mean age of 75.5 (60 – 89) years were included. The revision stem was inserted via a modified transgluteal approach (n = 16) or classical transfemoral approach (n = 2). The mean follow-up was 18.5 months, with a mean Harris Hip Score of 72.5 ± 18.7 (35.0 – 99.0) points. The fracture healing rate was 94.4% (n = 17) with osseous integration according to Engh in all cases. Dislocations of the greater trochanter were recorded in seven patients (38.9%). According to Beals and Towers, all results were rated excellent or good. No implant-related failure or relevant subsidence during this time was observed. Major complications were observed in five patients with two periprosthetic joint infections and two cases of major revision surgery. Conclusion This study assessing Vancouver B2/3 fractures shows reproducible, good, short-term results in terms of subsidence and clinical functional outcome by the use of a modular revision stem. The transfemoral approach together with the modular stem allows for a stable fixation and good fracture healing. However, our data and review of the literature also documents the difficulties and higher complication rate associated with Vancouver B2/3 fractures.

High rates of implant fracture of a generic polished tapered femoral stem

Objectives: Cemented polished tapered stems have demonstrated excellent long-term outcomes. Based on this concept, many generic tapered stems have been released into the market. The aim of this study was to evaluate implant-related complications of 1 specific stem design. Methods: Between 2010 and 2017, 315 total hip replacements were performed using a Fortress stem (Biotechni, La Ciotat, France). Patient records and radiology were retrospectively reviewed for implant-related complications. A failure analysis was performed on the failed Fortress stems in order to determine the cause of premature failure. Results: 7 (2.2%) patients sustained a fracture of the neck of the implant after a mean of 5 years (range 50–81 months). All fractures were atraumatic, originating at the introducer inlet of the stem. All fractured occurred in obese patients (BMI >33 kg/m2) with a small sized prosthesis. Of these, there were 5 135° and 2 125° stems. Fracture risk was 23% (7/30) for patients with a small sized stem and a BMI >30 kg/m2. All cases were revised using a cement-in-cement technique or a cementless modular revision stem. Failure analysis on the retrieved stems revealed a stress riser at the bottom of the introducer inlet. Conclusions: An alarmingly high rate of early implant fractures was seen using this specific type of cemented stem, particularly when using smaller implant sizes in obese patients. Although based on a proven design, a specific modification led to a stress riser in the neck area, which resulted in a high incidence of implant failure. This series underlines the importance of a stepwise introduction into the market of new orthopaedic devices even when based on established concepts. Generic stems may not behave as the original stem upon which it was designed.

Revision of Sivash Endoprosthesis 41 Years after Primary Operation

Clinical observation of a female patient who at the age of 16 underwent total hip replacement by Sivash implant due to congenital left hip dislocation is presented. The reason for revision intervention that was performed in 41 years after primary arthroplasty was the fracture of the implant stem. The stem was removed via 2 transfemoral approaches. Modular revision stem for distal fixarion was implanted. Treatment result is considered to be satisfactory: no pain is present and weight bearing ability is restored.