Periprosthetic Fractures of the Proximal Femur: Modern Concepts

With the increasing demand for total hip arthroplasty in trauma and orthopedic departments, there is a sharp increase in periprosthetic fractures. Considering the high morbidity and mortality associated with these fractures, the orthopedic traumatologist must be prepared to address this problem. This article provides an algorithmic approach that will make it easy to classify and deliver the correct treatment.

256 Charcot-Marie-Tooth Disease as A Risk Factor for Periprosthetic Fractures in Tibiotalocalcaneal Fusion With Intramedullary Nailing

Aim The treatment for severe fixed hindfoot osteoarthritis secondary to Charcot-Marie-Tooth disease (CMT) disease is tibiotalocalcaneal (TTC) arthrodesis. In our centre, we have noticed a disproportionate rate of periprosthetic fractures in CMT patients following TTC arthrodesis with retrograde hindfoot nailing. The aim of this study was to test this hypothesis by evaluating our local cohort of TTC arthrodesis with retrograde hindfoot nailing. Method A retrospective review of patients who had TTC arthrodesis with intramedullary nailing was conducted over a seven-year period. Results There were 45 patients (30 male, 15 female) in our cohort. Forty-one patients achieved radiological and clinical fusion of their TTC arthrodesis. All three patients who had CMT sustained periprosthetic fracture at the tip of the nail at an average of 4 (range: 2.5 - 6) months from index operation. In comparison, no patients in the rest of the cohort sustained periprosthetic fractures. The nail position of the patients with CMT were central in both planes in all 3 patients. None of the patients with CMT had abutment of the cortex on either planes. Conclusions We found that there was a disproportionate rate of periprosthetic fractures in CMT patients in our cohort of TTC arthrodesis with retrograde hindfoot nailing. This suggests that CMT is a significant risk factor. The authors propose a longer nail to reduce the lever arm, with a long period of protected weight bearing till union. Elective removal of the nail to prevent this phenomenon from occurring should also be considered.

Vancouver B and C periprosthetic fractures around the cemented Exeter Stem: sex is associate with fracture pattern

Introduction The aim of this study was to identify factors associated with the level of periprosthetic fracture involving a cemented polished tapered stem: Vancouver B or Vancouver C. Methods A retrospective cohort study of 181 unilateral periprosthetic fractures involving Exeter stems was assessed by three observers (mean age 78.5, range 39–103; mean BMI 27.1, 17–39; 97 (54%) male). Patient demographics, deprivation scores, BMI and time since primary prosthesis were recorded. Femoral diameter, femoral cortical thickness, Dorr classification and distal cement mantle length were measured from calibrated radiographs. Interobserver reliability was calculated using intraclass correlation coefficients (ICCs). Univariate and multivariate analysis was performed to identify associations with Vancouver B or C fractures. Results 160/181 (88%) Vancouver B and 21/181 (12%) Vancouver C-level fractures occurred at a mean of 5.9 ± 5.4 years (0.2–26.5) following primary surgery. Radiographic measurements demonstrated excellent agreement (ICC > 0.8, p < 0.001). Mortality was significantly higher following Vancouver C compared to B fractures: 90 day 14/160 Vs 5/21 (p = 0.05); 1 year 29/160 Vs 8/21 (p = 0.03). Univariate analysis demonstrated that Vancouver C fractures were associated with female sex, bisphosphonate use, cortical bone thickness, and distal cement mantle length (p < 0.05). On multivariate analysis, only female sex was an independent predictor of Vancouver C-level fractures (R2 =0.354, p = 0.005). Conclusion Most PFFs involving the Exeter stem design are Vancouver B-type fractures and appear to be independent of osteoporosis. In contrast, Vancouver C periprosthetic fractures display typical fragility fracture characteristics and are associated with female sex, thinner femoral cortices, longer distal cement mantles and high mortality.