Changing practice to a new-generation triple-taper collared femoral component reduces periprosthetic fracture rates after primary total hip arthroplasty.

Aims: Periprosthetic femoral fracture (PPF) is a major complication following total hip arthroplasty (THA). Uncemented femoral components are widely preferred in primary THA, but are associated with higher PPF risk than cemented components. Collared components have reduced PPF rates following uncemented primary THA compared to collarless components, while maintaining similar prosthetic designs. The purpose of this study was to analyze PPF rate between collarless and collared component designs in a consecutive cohort of posterior approach THAs performed by two high-volume surgeons. Methods: This retrospective series included 1,888 uncemented primary THAs using the posterior approach performed by two surgeons (PKS, JMV) from January 2016 to December 2022. Both surgeons switched from collarless to collared components in mid-2020, which was the only change in surgical practice. Data related to component design, PPF rate, and requirement for revision surgery were collected. A total of 1,123 patients (59.5%) received a collarless femoral component and 765 (40.5%) received a collared component. PPFs were identified using medical records and radiological imaging. Fracture rates between collared and collarless components were analyzed. Power analysis confirmed 80% power of the sample to detect a significant difference in PPF rates, and a Fisher's exact test was performed to determine an association between collared and collarless component use on PPF rates. Results: Overall, 17 PPFs occurred (0.9%). There were 16 fractures out of 1,123 collarless femoral components (1.42%) and one fracture out of 765 collared components (0.13%; p = 0.002). The majority of fractures (n = 14; 82.4%) occurred within 90 days of primary THA. There were ten reoperations for PPF with collarless components (0.89%) and one reoperation with a collared component (0.13%; p = 0.034). Conclusion: Collared femoral components were associated with significant decreases in PPF rate and reoperation rate for PPF compared to collarless components in uncemented primary THA. Future studies should investigate whether new-generation collared components reduce PPF rates with longer-term follow-up.

Cemented Femoral Fixation in Total Hip Arthroplasty Reduces the Risk of Periprosthetic Femur Fracture in Patients 65 Years and Older: An Analysis From the American Joint Replacement Registry.

BACKGROUND: Periprosthetic femur fracture (PPFx) is a devastating complication after total hip arthroplasty (THA). Despite concerns for increased PPFx, cementless fixation predominates in the United States. This study used the American Joint Replacement Registry to compare PPFx risk between cemented and cementless femoral fixation for THA. METHODS: An analysis of primary THA cases in patients aged 65 years and more was performed with the American Joint Replacement Registry data linked to Centers for Medicare and Medicaid Services data from 2012 to 2020. Analyses compared cemented to cementless femoral fixation. We identified 279,052 primary THAs, 266,040 (95.3%) with cementless and 13,012 (4.7%) with cemented femoral fixation. Cox proportional hazard regression analyses evaluated the association of fixation and PPFx risk, while adjusting for sex, age, and competing risk of mortality. Cumulative incidence function survival curves evaluated time to PPFx. RESULTS: Age ≥ 80 years (P < .0001) and women (P < .0001) were associated with PPFx. Compared to cemented stems, cementless stems had an elevated risk of PPFx (Hazards Ratio 7.70, 95% Confidence interval 3.2-18.6, P < .0001). The cumulative incidence function curves demonstrated an increased risk for PPFx across all time points for cementless stems, with equal magnitude of risk to 8 years.` CONCLUSION: Cementless femoral fixation in THA continues to predominate in the United States, with cementless femoral fixation demonstrating increased risk of PPFx in patients aged 65 years or more. Surgeons should consider greater use of cemented femoral fixation in this population to decrease the risk of PPFx.

Prophylactic Cerclage Cabling Decreases the Intraoperative Periprosthetic Fracture Rate during Cement-Less Total Hip Arthroplasty in Patients with Severe Developmental Hip Dysplasia.

PURPOSE OF THE STUDY Cementless stems in highly dysplastic hips are considered to increase the risk of femoral fracture and associated morbidity. Several authors speculated to use prophylactic cabling in this patient group to prevent intraoperative fractures. This study aims to reveal objective results regarding the perioperative complications in a large and consecutive patient group with respect to use of prophylactic cabling. MATERIAL AND METHODS A retrospective comparative study was planned. A total of 122 consecutive patients with dysplastic hips of Crowe type 3 or 4, operated on with total hip arthroplasty (THA) and shortening osteotomy using a rectangular femoral stem were included. Patients were stratified according to use of a diaphyseal prophylactic cerclage cable. Perioperative complications were recorded. Clinical outcome was measured in terms of Harris Hip Score and Visual Analog Scale (VAS) for pain. All results were compared between the groups. RESULTS The mean follow-up time was 27 months. Two (2%) versus five (14%) patients had a fracture at the diaphyseal level in cabled versus non-cabled groups. Difference between groups was statistically significant (p=0.01). Relative risk of fracture in case of a non-cabling was 5.8 (p=0.03). Eleven (9%) patients had a non-displaced fracture at the metaphyseal level. No significant differences were detected with respect to preoperative clinical outcome scores or change in these scores between groups. CONCLUSIONS Femoral diaphyseal fracture rates are low when cementless, rectangular stems are used in dysplastic high riding hips. Prophylactic cerclage cabling further decreases the fracture risk and eases treatment in case of a fracture without causing additional complications and therefore is recommended. Key words: intraoperative fracture, periprosthetic fracture, total hip arthroplasty, cerclage cabling, developmental hip dysplasia, transverse shortening osteotomy.

Preventive bilateral femoral nailing in atypical femoral fracture non responder to anabolic therapy: case report and mini-review.

Currently bisphosphonates are the main antiresorptive medications used in osteoporosis. However, a prolonged use of these drugs is associated to an increased risk of atypical femoral fractures, especially in patients suffering from others predisposing clinical conditions. This report describes a case of a woman presenting bilateral impending femoral fracture initially treated with bisphosphonates suspension and intramedullary nailing of right femur. Despite anabolic therapy, the patient presented progression of incomplete contralateral femoral fracture which required a second surgical treatment.

Use of a circular fixator construct to facilitate closed reduction and percutaneous stabilization of a distal femoral physeal fracture in a dog.

Background: Fractures of the distal femoral physis are the most common physeal fracture sustained by skeletally immature dogs. Reduction and stabilization of these fractures can sometimes be achieved through closed reduction, primarily in fractures that are nominally displaced. Circular external fixator constructs have been used to assist in indirect, closed reduction of fractures at other anatomic locations in dogs and this report describes application of this method to reduce a displaced Salter-Harris type II fracture of the distal femur in a 1-year-old dog. Case Description: A 1-year-old female spayed Akita was referred for treatment of a Salter-Harris type II fracture of the right distal femur. The epiphyseal segment was laterally and slightly caudally displaced. Multiple attempts to manually reduce the fracture during surgery were unsuccessful, so a two-ring circular external fixator construct was applied to facilitate distraction and reduction. The construct was applied by placing a medial-to-lateral Kirschner wire in both the mid-femoral diaphysis and in the distal femoral epiphysis. Distraction of the construct provided sufficient separation of the fracture segments to facilitate near anatomic reduction. The fracture was stabilized with two percutaneously placed Steinmann pins placed in Rush fashion. Radiographic union was confirmed 5 weeks after surgery. The dog was not lame and was bearing more weight on the right pelvic limb, as assessed using force plate analysis, 9 months following surgery. Goniometric measurements of stifle range of motion and thigh muscle circumference were similar between the pelvic limbs. Conclusion: Application of a two-ring circular construct would appear to be useful to facilitate closed reduction and percutaneous stabilization of distal femoral physeal fractures.

Risk factors for femoral fracture in lateral decubitus direct anterior approach total hip arthroplasty using conventional stems: a retrospective analysis.

OBJECTIVE: To provide guidelines for surgery and reduce the incidence of fracture, this study analyzed the relationship between femoral fracture and related factors in direct anterior approach (DAA) total hip arthroplasty (THA) in the lateral decubitus position. METHOD: A retrospective series of 273 consecutive patients who underwent THA with the DAA in the lateral decubitus position was analyzed. Each surgery was performed by the same surgeon with a conventional operation bed and femoral stem. The correlations between the incidence of fracture and sex, age, body mass index (BMI), height, osteoporosis, the anterior superior iliac spine-greater trochanter distance (ASIS-GTD), and hip joint disease were analyzed by univariate analysis and logistic regression analysis. RESULTS: Among all hip arthroplasty procedures, 35 hips had femoral fractures, including 30 greater trochanter fractures, 4 proximal femoral splits, and 1 femoral perforation. The incidence of fracture was 12.82%. Univariate analysis showed no significant difference in the incidence of fracture by sex, BMI, or age. However, osteoporosis caused an increase in the incidence of fracture, while the incidence of fracture decreased as height and the ASIS-GTD increased. The incidence of femoral neck fracture was lower in cases of osteonecrosis of the femoral head than in cases of other diseases. Logistic regression showed a significant correlation between osteoporosis, the ASIS-GTD, and fractures. Patients with osteoporosis had a high possibility of fracture (OR = 2.414); the possibility of fracture decreased with increasing ASIS-GTD (OR = 0.938). CONCLUSION: Lateral decubitus DAA THA can be successfully performed using a conventional operation bed and stem, effectively saving medical resources. Osteoporosis and a shorter ASIS-GTD were independent risk factors for femoral fracture.

Introduction of a New Treatment Algorithm Reduces the Number of Periprosthetic Femoral Fractures After Primary Total Hip Arthroplasty in Elderly Females.

BACKGROUND: Increasing global usage of cementless prostheses in total hip arthroplasty (THA) presents a challenge, especially for elderly patients. To reduce the risk of early periprosthetic femoral fractures (PFFs), a new treatment algorithm for females older than 60 years undergoing primary THA was introduced. The aim of this study was to determine the impact of the new treatment algorithm on the early risk of perioperative and postoperative PFFs and guideline compliance. METHODS: A total of 2405 consecutive THAs that underwent primary unilateral THA at our institution were retrospectively identified in the period January 1, 2013-December 31, 2018. A new treatment algorithm was introduced on April 1, 2017 with female patients aged older than 60 years intended to receive cemented femoral components. Before this, all patients were scheduled to receive cementless femoral components. Demographic data, number of perioperative and postoperative PFFs, and surgical compliance were recorded, analyzed, and intergroup differences compared. RESULTS: The utilization of cemented components in female patients older than 60 years increased from 12.3% (n = 102) to 82.5% (n = 264). In females older than 60 years, a significant reduction in the risk in early postoperative and intraoperative PFF after introduction of the new treatment algorithm was seen (4.57% vs 1.25%; P = .007 and 2.29% vs 0.31%; P = .02, respectively). Overall risk for postoperative and intraoperative fractures combined was also reduced in the entire cohort (4.1% vs 2.0%; P = .01). CONCLUSION: Use of cemented fixation of the femoral component in female patients older than 60 years significantly reduces the number of PFFs. Our findings support use of cemented femoral fixation in elderly female patients.

A Calcar Collar Is Protective Against Early Torsional/Spiral Periprosthetic Femoral Fracture: A Paired Cadaveric Biomechanical Analysis.

BACKGROUND: Periprosthetic fracture is a leading reason for readmission following total hip arthroplasty. Most of these fractures occur during the early postoperative period before bone ingrowth. Before ingrowth occurs, the femoral component can rotate relative to the femoral canal, causing a spiral fracture pattern. We sought to evaluate, in a paired cadaver model, whether the torsional load to fracture was higher in collared stems. The hypothesis was that collared stems have greater load to fracture under axial and torsional loads compared with collarless stems. METHODS: Twenty-two cadaveric femora (11 matched pairs) with a mean age of 77 ± 10.2 years (range, 54 to 90 years) were harvested. Following dissection, the femora were evaluated with use of a dual x-ray absorptiometry scanner and T scores were recorded. We utilized a common stem that is available with the same intraosseous geometry with and without a collar. For each pair, 1 femur was implanted with a collared stem and the contralateral femur was implanted with a collarless stem with use of a standard broaching technique. A compressive 68-kg load was applied to simulate body weight during ambulation. A rotational displacement was then applied until fracture occurred. Peak torque prior to fracture was measured with use of a torque meter load cell and data acquisition software. RESULTS: The median torque to fracture was 65.4 Nm for collared stems and 43.1 Nm for uncollared stems (p = 0.0014, Wilcoxon signed-rank test). The median T score was -1.95 (range, -4.1 to -0.15). The median difference in torque to fracture was 29.18 Nm. As expected in each case, the mode of failure was a spiral fracture around the implant. CONCLUSIONS: Collared stems seemed to offer a protective effect in torsional loading in this biomechanical model comparing matched femora. CLINICAL RELEVANCE: These results may translate into a protective effect against early periprosthetic Vancouver B2 femoral fractures that occur before osseous integration has occurred.

Is There an Association Between Prophylactic Femur Stabilization and Survival in Patients with Metastatic Bone Disease?

BACKGROUND: The femur is the most common site of metastasis in the appendicular skeleton, and metastatic bone disease negatively influences quality of life. Orthopaedic surgeons are often faced with deciding whether to prophylactically stabilize an impending fracture, and it is unclear if prophylactic fixation increases the likelihood of survival. QUESTIONS/PURPOSES: Is prophylactic femur stabilization in patients with metastatic disease associated with different overall survival than fixation of a complete pathologic fracture? METHODS: We performed a retrospective, comparative study using the national Veterans Administration database. All patient records from September 30, 2010 to October 1, 2015 were queried. Only nonarthroplasty procedures were included. The final study sample included 950 patients (94% males); 362 (38%) received prophylactic stabilization of a femoral lesion, and 588 patients (62%) underwent fixation of a pathologic femur fracture. Mean followup duration was 2 years (range, 0-7 years). We created prophylactic stabilization and pathologic fracture fixation groups for comparison using Common Procedural Terminology and ICD-9 codes. The primary endpoint of the analysis was overall survival. Univariate survival was estimated using the Kaplan-Meier method; between-group differences were compared using the log-rank test. Covariate data were used to create a multivariate Cox proportional hazards model for survival to adjust for confounders in the two groups, including Gagne comorbidity score and cancer type. RESULTS: After adjusting for comorbidities and cancer type, we found that patients treated with prophylactic stabilization had a lower risk of death than did patients treated for pathologic femur fracture (hazard ratio = 0.75, 95% CI, 0.62-0.89; p = 0.002). CONCLUSIONS: In the national Veterans Administration database, we found greater overall survival between patients undergoing prophylactic stabilization of metastatic femoral lesions and those with fixation of complete pathologic fractures. We could not determine the cause of this association, and it is possible, if not likely, that patients treated for fracture had more aggressive disease causing the fracture than did those undergoing prophylactic stabilization. Currently, most orthopaedic surgeons who treat pathological fractures stabilize the fracture prophylactically when reasonable to do so. We may be improving survival in addition to preventing a pathological fracture; further study is needed to determine whether the association is cause-and-effect and whether additional efforts to identify and treat at-risk lesions improves patient outcomes. LEVEL OF EVIDENCE: Level III, therapeutic study.

The limitations of today's clinical guidance: Atypical femoral fracture and long-term bone-modifying agents in the oncology setting.

While bone-modifying agents such as bisphosphonates and denosumab are crucial to preventing skeletal-related events in patients with bone metastases, the optimal duration remains undefined. Extended duration may be associated with adverse effects such as osteonecrosis of the jaw and atypical femoral fracture. Although uncommon, atypical femoral fracture represents a serious consequence of prolonged bone-modifying agent use and are characterized by a prodrome and distinct radiographic findings. The oncology setting encompasses a unique set of atypical femoral fracture risk factors and considerations, with hormonal therapy in early stage disease, bone metastases in the advanced setting, and new targeted agents that may affect bone homeostasis. As outcomes in cancer treatment continue to improve, the questions of risks versus benefits of long-term bone-modifying agents and how to mitigate atypical femoral fracture risk become increasingly pertinent.

Duration of Bisphosphonate Drug Holidays and Associated Fracture Risk.

BACKGROUND: Discontinuation of bisphosphonates (BP) or a "drug holiday" after several years of treatment is increasingly common. However, the association of drug holiday duration with future fracture risk is unclear. OBJECTIVES: We evaluated the rate of fracture in relation to various lengths of drug holidays among women receiving long-term BP therapy. RESEARCH DESIGN: Observational cohort study using US Medicare data 2006-2016. Incidence rates (IRs) and Cox proportional hazards models were used to evaluate the rate and adjusted hazard ratios (aHRs) controlling for potential confounders. SUBJECTS: Women aged 65 years and above enrolled in fee-for-service Medicare who had been adherent (≥80%) to alendronate, risedronate, or zoledronate for ≥3 years. MEASURES: Hip, humerus, distal forearm, and clinical vertebral fracture. RESULTS: Among 81,427 eligible women observed for a median (interquartile range) of 4.0 (2.5, 5.3) years, 28% of women underwent a drug holiday. In the alendronate cohort (73% overall), the IR of hip fracture among women who discontinued BP for >2 years was 13.2 per 1000 person-years. Risk was increased (aHR=1.3, 1.1-1.4) versus continuing therapy (IR=8.8, referent). Rates were elevated for humerus fracture with discontinuation >2 years (aHR=1.3, 1.1-1.66) and for clinical vertebral fracture with discontinuation >2 years (aHR=1.2, 1.1-1.4). Results were similar for risedronate, zoledronate, and ibandronate for hip and clinical vertebral fracture. CONCLUSION: Discontinuing alendronate beyond 2 years was associated with increased risk of hip, humerus, and clinical vertebral fractures.

Treadmill exercise prevents reduction of bone mineral density after myocardial infarction in apolipoprotein E-deficient mice.

AIMS: Recent clinical studies demonstrated the association between myocardial infarction (MI) and osteoporotic fractures. We examined whether MI causes bone loss and the effects of exercise training on bone in mice after MI. METHODS: We created a MI model in 16-week-old male apolipoprotein E-deficient mice (n = 42), which were randomly assigned to exercise group (MI-Ex) and sedentary group (MI-Sed). We also performed sham operations in other mice (n = 10). Treadmill exercise training was performed from one week after operation to eight weeks. At eight weeks, the bone parameters of the femur were measured by quantitative computed tomography, followed by histological analysis (n = 10-17). RESULTS: Bone mineral density (BMD) of the femur was significantly decreased in the MI-Sed group as compared with the sham group (P < 0.001), whereas the BMD was significantly increased in the MI-Ex group as compared with the MI-Sed group (P < 0.05). In histological analysis, Rho-associated coiled-coil kinase 2 and tartrate-resistant acid phosphate positive (bone resorptive) area in distal femur were significantly increased in the MI-Sed group as compared with the sham group (P < 0.05), whereas those parameters were significantly decreased in the MI-Ex group as compared with the MI-Sed group (P < 0.05). In contrast, alkaline phosphatase (ALP)-positive (bone-forming) area was significantly decreased in the MI-Sed group as compared with the sham group (P < 0.05), whereas ALP-positive area was significantly increased in the MI-Ex group as compared with the MI-Sed group (P < 0.05). CONCLUSIONS: The present study demonstrates that MI reduces BMD and treadmill exercise training prevents the reduction of BMD in apolipoprotein E-deficient mice.

Inter-implant fractures: an unmet medical need-a preventive approach proposal.

Inter-implant fractures are associated with reduced quality of life and increased 1-year mortality. For that reason, we propose, instead of treating, a novel, preventative surgical approach that involves splinting the inter-implant femoral shaft interval. In patients with a previous femoral implant in whom a second surgery for new material implantation was necessary (including knee or hip arthroplasty, plate or femoral nailing), an overlapping technique using the minimally invasive plate osteosynthesis technique was performed during the second surgery. Nine patients were included, all females with median (range) age of 78 (55-88) years. No surgery-related complications or mortality occurred. Two patients suffered fractures from a casual fall postoperatively with no implant failure or hospital admission required. In conclusion, instead of treating such fractures after they occur, we propose an effective, safe and reproducible preventative surgical approach, not previously reported, which involves internal femoral splinting, a plate and the minimally invasive plate osteosynthesis technique.