The influence of femoral component design on postoperative periprosthetic femoral fracture after uncemented direct anterior total hip arthroplasty in the elderly.

INTRODUCTION: Aging populations and expanding indications will greatly increase the volume of total hip arthroplasty (THA) in all age groups, including patients over 70 years old. Minimally invasive, uncemented direct anterior THA offers potential advantages for treating elderly patients. However, literature indicates higher risks of postoperative periprosthetic femur fractures (PPFFs) with both direct anterior THA and uncemented femoral stems. This retrospective study investigates the influence of femoral stem design on PPFF incidence in uncemented direct anterior THA among patients older than 70 years. METHODS: 557 primary THAs in patients aged 70 or over were reviewed for PPFFs from a consecutive series of 2011 patients undergoing direct anterior THA from a fellowship-trained adult reconstruction surgeon from 2015 to 2020. Exclusion criteria included age (<70) and posterior approach. For the first cohort of 361 patients (79 of which passed exclusion criteria) the surgeon used a single-tapered, proximally porous coated, collarless titanium stem. For the next 1650, (478 of which passed exclusion), the surgeon used a dual-tapered, collared, hydroxyapatite-coated titanium stem. Included patients were carefully monitored until March 2021 for PPFFs. A Fisher's exact test was used to compare the incidence PPFFs between the 2 implant designs. RESULTS: 2 of 79 (2.5%) patients had atraumatic PPFFs at an average of 19.5 days post-operatively in the first cohort. Both experienced a Vancouver type B2 periprosthetic fracture and required femoral revision. No patients (0/478, 0%) in the second group sustained a PPFF. (P = 0.0199). CONCLUSION: In this comparison, the dual-taper, hydroxyapatite-coated implant had a significantly lower PPFF rate among elderly patients than a single-taper, proximally porous stem without a collar.

Particulate bone grafting of osteolytic femoral lesions around stable cementless stems.

The purpose of the current study was to evaluate the effect of particulate grafting for proximal femoral osteolysis in the presence of a well-fixed cementless femoral stem at the time of acetabular liner change or revision. Sixteen patients (17 hips) who averaged 51 years of age underwent curettage and packing of proximal femoral osteolytic lesions with cancellous allograft. Modular acetabular liners were changed in 11 patients, acetabular revisions were performed in six patients, and femoral heads were exchanged in all patients. The femoral component was retained in all patients. The majority of patients were asymptomatic before revision surgery. The size of the femoral osteolytic lesions was measured preoperatively and postoperatively with anteroposterior and Lauenstein lateral radiographs of the hip. Preoperatively, the average lesion was 41 x 16 mm on the anteroposterior view and 18 x 7 mm on the lateral view. The average clinical and radiographic followup was 39 and 32 months, respectively, with a minimum followup of 24 months. All but one patient remained asymptomatic during the followup period and no femoral stem showed evidence of loosening. The size of the femoral osteolytic lesion averaged 16 x 6 mm on the anteroposterior view and 6 x 2 mm on the lateral view at most recent followup. In 15 of 17 patients, the size of the femoral lesion had regressed. This technique seems to be a viable means of preventing progressive osteolysis and femoral loosening while preserving bone stock for future reconstruction.

Lower extremity deformities associated with thrombocytopenia and absent radius syndrome.

The cases of 11 patients with the syndrome of thrombocytopenia and absent radius (TAR syndrome) who presented at two institutions between 1970 and 1996 were reviewed. Knee deformities have been well documented in thrombocytopenia and absent radius syndrome, but an inordinate frequency of other lower extremity problems needing orthopaedic attention was seen. Five of the 11 patients with thrombocytopenia and absent radius syndrome studied had knee deformities, but seven of the 11 had 11 other lower extremity deformities. This article documents all of the lower extremity problems seen in the seven patients with thrombocytopenia and absent radius syndrome with anomalies other than those of the knee.

The influence of preoperative radiation therapy on morbidity and mortality for transhiatal esophagectomy.

To assess the morbidity and mortality of preoperative radiation therapy (RT), the authors reviewed 37 consecutive patients who underwent transhiatal esophagectomy for carcinoma of the esophagus. Twelve patients received no RT, 13 patients received RT only to the neck, and 12 received RT to the chest (three of these received radiation therapy to the chest and neck). Preoperative chest RT did not significantly increase postoperative fistula formation but was associated with significantly higher operative mortality, overall complication rate, and time on ventilators than either the patients receiving neck RT alone or no RT (P less than 0.05). Postoperative hospital stay was longer and intraoperative blood loss greater for the chest RT group compared to those with no RT (P less than 0.05). Neck RT did not result in these complications (P = NS). The authors conclude that preoperative chest RT is associated with significant postoperative morbidity and mortality.

The resolution model: a comprehensive treatment framework in sexual abuse.

The Resolution Model presents an original framework for the treatment of sexually abused children and their families. It differs from earlier models by offering coordinated guidelines for assessment and treatment modalities that apply to various family members. The key to the treatment process is based on each party's ability to assume responsibility for his or her role in the trauma and its resolution. Each stage of treatment is clearly delineated, and specific goals and tasks are suggested.

Ultranarrow linewidth waveguide excimer lasers.

We have constructed a single longitudinal mode XeCl laser using microwave discharge waveguide laser technology. The pulse duration, repetition rate, and simplicity of construction associated with waveguide excimer lasers lend this system unique capabilities and a broad utility for interfacing with other excimer devices. The coherence length of the laser emission has been found to be ~6 m with a corresponding bandwidth of <22 MHz that is near the transform limit. The laser has been used to demonstrate pulsed UV Doppler velocity measurement in a simple homodyne configuration.

High-repetition-rate XeCl waveguide laser without gas flow.

Operation of a microwave discharge XeCl laser at pulse-repetition rates extending to 8 kHz without flow of the laser gas is reported. Present limits on pulse-repetition rate appear to be imposed by thermally induced refractive-index gradients.

New laser source technology.

Over the past 5 to 8 years several new laser sources have been developed as a result of R & D efforts stimulated by a growing number of laser applications. Four families of new devices-semiconductor diod laser arrays, free electron lasers, rare gas halide excimer sources, and several new tunable solid-state lasers-show particular promise.

Some emerging applications of lasers.

New laser applications are emerging in almost every field of science. Many of them show both a high degree of technical sophistication and broad practical utility. The progress being made is illustrated by specific applications in three areas: laser microchemistry, optical disk data storage, and remote sensing.