Low Rate of Early Periprosthetic Fractures in Direct Anterior Total Hip Arthroplasty with a Triple-Tapered Wedge Stem.

INTRODUCTION: Utilization of the direct anterior approach (DAA) for total hip arthroplasty (THA) has been steadily increasing in recent years. While the DAA may offer some benefits compared to other approaches, there are still risks involved including relatively higher rates of periprosthetic femur fractures, especially when combined with cementless femoral stem use. The purpose of this study is to evaluate the early postoperative femoral complications with a short triple-wedge tapered stem used in primary THA via a DAA. MATERIALS AND METHODS: A retrospective review was conducted of the arthroplasty registry of our institution from April 2022 to August 2023 to identify patients who underwent a primary THA via a DAA with the Short Medacta Stem (SMS) (Medacta International, Castel San Pietro, Switzerland). Patients were excluded if the stem was used for a revision surgery, they were within 90 days of surgery, or they refused research consent. Inclusion criteria was met in 262 patients (302 hips). Data was collected after reviewing the chart, and reports and radiographic measurements, including Dorr type and canal fit ratios, were obtained from preoperative and postoperative radiographs, respectively. RESULTS: A total of 302 total hips were included, 161 patients were male (53.3%) and 141 were female (46.7%), with an average age of 66.5 years (27-88, +/- 10.7 years). Average follow up was 0.3 years (range, 0.05-1.71 years). The majority of patients had a Dorr B femur (81.7%). The Median stem size used was an 8 (range, 2-15), and 89.4% of those had a collar. Average canal fill ratio was 0.83 (range, 0.43-0.98, +/- 0.07). Overall, there were two Vancouver B2a periprosthetic femoral shaft fractures (0.66%) that required revision surgery to a modular stem. In addition, there were two Vancouver Ag greater trochanteric fractures (0.66%) with acceptable alignment that did not require revision surgery. Demographic information about the patients with femoral complications is summarized in Table I. Average age of patients with femoral complications was 69.5 years, with an average canal fit ratio of 0.88. CONCLUSION: We found that the triple-wedge implant had a low rate of early femoral complication in primary THA from an anterior approach and is safe for use in THA from a DAA. More follow up is needed to evaluate continuing implant survivorship and patient outcomes.

Biomechanical comparison of composite and cadaveric humeri models in experiments on operated humeral shaft fractures.

A study was undertaken to determine how well contacting fracture fragments of composite bone replicated the behavior of fracture fragments in real bone. Ten composite and ten real humeral diaphyses were transected and reconstructed with limited-contact dynamic-compression plates. Two screws were placed on each side of the transection site and a calibrated electronic sensor sheet was placed between the imitated fracture fragments. After insertion of the distal screws, pressure measurements were made during insertion of the first proximal screw in compression mode, during insertion of the second screw in compression mode after loosening the first screw, and finally after retightening the first screw. The process was repeated after bending the plate. The contact area, the net compression force and the average compressive stress were computed and statistically compared. The composite bone and cadaveric bone differed in contact area and compressive stress but not in net compressive force. Plate bending did not produce a significant difference between composite and cadaveric bone. The results indicate that composite bone does not reproduce all the local fracture fragment conditions so that hardware testing in composite bone should proceed carefully. A gap between fracture fragments as is often used in comminuted fracture tests may remain as the most appropriate situation for fracture hardware testing.

A biomechanical comparison of superior ramus plating versus intramedullary screw fixation for unstable lateral compression pelvic ring injuries,,.

INTRODUCTION: Management of the anterior component of unstable lateral compression (LC) pelvic ring injuries remains controversial. Common internal fixation options include plating and superior pubic ramus screws. These constructs have been evaluated in anterior-posterior compression (APC) fracture patterns, but no study has compared the two for unstable LC patterns, which is the purpose of this study. METHODS: A rotationally unstable LC pelvic ring injury was modeled in 10 fresh frozen cadaver specimens by creating a complete sacral fracture, disruption of posterior ligaments, and ipsilateral superior and inferior rami osteotomies. All specimens were repaired posteriorly with two fully threaded 7 mm cannulated transiliac-transsacral screws through the S1 and S2 corridors. The superior ramus was repaired with either a 3.5 mm pelvic reconstruction plate (n = 5) or a bicortical 5.5 mm cannulated retrograde superior ramus screw (n = 5). Specimens were loaded axially in single leg support for 1000 cycles at 400 N followed by an additional 3 cycles at 800 N. Displacement and angulation of the superior and inferior rami osteotomies were measured with a three-dimensional (3D) motion tracker. The two fixation methods were then compared with Mann-Whitney U-Tests. RESULTS: Retrograde superior ramus screw fixation had lower average displacement and angulation than plate fixation in all categories, with the motion at the inferior ramus at 800 N of loading showing a statistically significant difference in angulation. CONCLUSION: Although management of the anterior ring in unstable LC injuries remains controversial, indications for fixation are becoming more defined over time. In this study, the 5.5 mm cannulated retrograde superior ramus screw significantly outperformed the 3.5 mm reconstruction plate in angulation of the inferior ramus fracture at 800 N. No other significance was found, however the ramus screw demonstrated lower average displacements and angulations in all categories for both the inferior and superior ramus fractures.

Use of Tantalum Trabecular Metal Cones for Management of Nonunion of the Distal Femur with Segmental Bone Defects: Technique and Case Series.

INTRODUCTION: Segmental bone loss in the distal femur presents a challenge for reconstruction regardless of etiology. Use of tantalum trabecular metal cones with intramedullary fixation and autologous bone graft may be used as a salvage technique in difficult situations where other options have either been exhausted or are unavailable. CASE REPORT: Surgical planning and technique for this approach to reconstruction are described. A retrospective review of five cases with >1 year of follow-up was performed to provide radiographic and clinical outcomes. All five patients had satisfactory outcomes with clinical union and retention of implants at final follow-up (average >4 years). CONCLUSIONS: Use of tantalum metal cones for reconstruction of distal femur nonunion with segmental bone defects can be a successful technique in a complex group of patients.

Publication Rates of Posters From the Orthopaedic Trauma Association Annual Meeting 2011-2016: Posters Are Not Second Rate.

OBJECTIVE: To determine the publication rate of posters presented at the OTA annual meeting from 2011 to 2016. METHODS: All posters presented at the OTA annual meetings from 2011 to 2016 were identified from the OTA's official website and confirmed through review of the OTA official programs. This information was then used to direct a search, and if the presentation was associated with a publication, publishing information was entered into the database. RESULTS: From 2011 to 2016, there were a total of 875 posters with 473 associated publications (54%). The highest rate of publication was 64.1% of posters published in 2012. The posters were published at an average of 19.4 months after presentation. One hundred sixty posters were published in the Journal of Orthopaedic Trauma (35%). CONCLUSION: Our research demonstrated a 54% publication rate over a 6-year period of posters presented at the OTA annual meetings. This rate is higher than other publication rates for podium presentations in other societies (eg, American Academy of Orthopaedic Surgeons and American Academy for Surgery of the Hand). This validates the quality of research presented in poster format at the OTA annual meeting.

Epidemiology of Upper Extremity Injuries in NCAA Men's and Women's Ice Hockey.

BACKGROUND: Ice hockey is a physically demanding sport where athletes are susceptible to a variety of injuries. Several studies reported the overall injury rates in ice hockey; however, there is a paucity of information on upper extremity (UE) injuries among collegiate ice hockey players. PURPOSE: To describe the epidemiology of UE injuries among collegiate male and female ice hockey players with NCAA (National Collegiate Athletic Association) injury surveillance data from 2004-2005 to 2013-2014. STUDY DESIGN: Descriptive epidemiology study. METHODS: Data were obtained from the NCAA Injury Surveillance Program for all UE injuries sustained during the academic years 2004-2005 to 2013-2014. Injury rates, rate ratios (RRs), and injury proportion ratios were reported with 95% CIs. RESULTS: During the 10 years studied, the overall rate of UE injuries for men was higher than that for women (236 vs 125 injuries per 100,000 athlete-exposures [AEs]; RR, 1.89; 95% CI, 1.67-2.15). UE injuries sustained during either pre- or postseason were approximately 3 times higher for men than for women (preseason: 149 vs 53 per 100,000 AEs; RR, 2.83; 95% CI, 1.69-4.74; postseason: 143 vs 49 per 100,000 AEs; RR, 2.91; 95% CI, 1.33-6.38). The overall injury rate was highest during the regular season (men: 257 per 100,000 AEs; 95% CI, 242-272; women: 143 per 100,000 AEs; 95% CI, 126-160). Additionally, the injury rate for men and women was higher during competition than practice (men: 733 vs 83 per 100,000 AEs; 95% CI, 687-780 and 75-92; women: 303 vs 64 per 100,000 AEs; 95% CI, 259-348 and 52-76). The most common injury observed was acromioclavicular joint sprain (men, 29.1%; women, 13.8%). For both groups, acromioclavicular joint injuries accounted for most non-time loss, moderate time loss (2-13 days), and severe time loss (≥14 days) injuries. CONCLUSION: Men and women sustained a significant number of UE injuries playing collegiate ice hockey during the period studied, with acromioclavicular joint sprain being the most common UE injury and the one that most frequently led to significant time loss. These data may provide insight for future injury prevention and guide improvements in training.

Isolation of human islets for autologous islet transplantation in children and adolescents with chronic pancreatitis.

Chronic pancreatitis is an inflammatory disease of the pancreas that causes permanent changes in the function and structure of the pancreas. It is most commonly a complication of cystic fibrosis or due to a genetic predisposition. Chronic pancreatitis generally presents symptomatically as recurrent abdominal pain, which becomes persistent over time. The pain eventually becomes disabling. Once specific medical treatments and endoscopic interventions are no longer efficacious, total pancreatectomy is the alternative of choice for helping the patient achieve pain control. While daily administrations of digestive enzymes cannot be avoided, insulin-dependent diabetes can be prevented by transplanting the isolated pancreatic islets back to the patient. The greater the number of islets infused, the greater the chance to prevent or at least control the effects of surgical diabetes. We present here a technical approach for the isolation and preservation of the islets proven to be efficient to obtain high numbers of islets, favoring the successful treatment of young patients.