Periprosthetic fractures about total knee arthroplasty.

Periprosthetic fracture after total knee arthroplasty presents a difficult complication for many orthopaedic surgeons. These fractures occur most frequently around the distal femur followed by the patella and then tibia. These fractures are frequently complicated by poor bone quality or compromised bone due to the presence of the implants. Surgical treatment is typically necessary and requires varied techniques of open fixation, intramedullary fixation, or revision arthroplasty. Outcomes of these injuries vary widely. This review aims to describe the epidemiology, classification, treatment options and outcomes for periprosthetic fractures following total knee arthroplasty.

Extremity fractures associated with ATVs and dirt bikes: a 10-year national epidemiologic study.

BACKGROUND: Morbidity and mortality of all-terrain vehicles and dirt bikes have been studied, as well as the association of helmet use and head injury. HYPOTHESIS/PURPOSE: The purpose of this study is to compare and contrast the patterns of extremity fractures associated with ATVs and dirt bikes. We believe there will be unique and potentially preventable injury patterns associated with dirt bikes and three-wheeled ATVs due to the poor stability of these vehicles. STUDY DESIGN: Descriptive epidemiology study. METHODS: The National Electronic Injury Surveillance System (NEISS) was used to acquire data for extremity fractures related to ATV (three wheels, four wheels, and number of wheels undefined) and dirt bike use from 2007 to 2012. Nationwide estimation of injury incidence was determined using NEISS weight calculations. RESULTS: The database yielded an estimate of 229,362 extremity fractures from 2007 to 2012. The incidence rates of extremity fractures associated with ATV and dirt bike use were 3.87 and 6.85 per 1000 participant-years. The largest proportion of all fractures occurred in the shoulder (27.2%), followed by the wrist and lower leg (13.8 and 12.4%, respectively). There were no differences in the distribution of the location of fractures among four-wheeled or unspecified ATVs. However, three-wheeled ATVs and dirt bikes had much larger proportion of lower leg, foot, and ankle fractures compared to the other vehicle types. CONCLUSIONS: While upper extremity fractures were the most commonly observed in this database, three-wheeled ATVs and dirt bikes showed increased proportions of lower extremity fractures. Several organizations have previously advocated for better regulation of the sale and use of these specific vehicles due to increased risks. These findings help illustrate some of the specific risks associated with these commonly used vehicles.

Quantitative assessment and characterization of glenoid bone loss in a spectrum of patients with glenohumeral osteoarthritis.

PURPOSE: Eccentric posterior bone loss and associated glenoid retroversion represent challenges to glenoid placement during total shoulder arthroplasty. This bone loss can lead to poor stability and perforation of the glenoid during arthroplasty. The purpose of this study was to evaluate the morphology of glenoid bone loss for a spectrum of osteoarthritis patients using 3D computed tomography imaging and simulation software. METHODS: This study included 29 patients with glenohumeral osteoarthritis treated with shoulder arthroplasty. Three-dimensional reconstruction of preoperative CT images was performed. Glenoid bone loss was measured at ten, vertically equidistant axial planes along the glenoid surface at four distinct anterior-posterior points on each plane. The images were fitted with modeled pegged glenoid implants to predict glenoid perforation. RESULTS: The 3D maps demonstrated greatest average bone loss posteriorly in the AP plane at the central axis of the glenoid in the SI plane. The average amount of bone loss was 3.85 mm. Walch A2 and B1 shoulders showed more central bone loss, while Walch B2 shoulders displayed more posterior and inferior bone loss. Patients with predicted peg perforation displayed significantly greater bone loss than those without predicted peg perforation (p = 0.037). Peg perforation was most common in Walch B2 shoulders occurring in the posterior direction involving the central and posterior-inferior peg. CONCLUSIONS: These data demonstrate an anatomic pattern of glenoid bone loss for different classes of glenohumeral arthritis. These findings can be used to develop various models of glenoid bone loss to guide surgeons, predict failures, and develop better glenoid implants. This study has been approved by the Cleveland Clinic IRB: Number 6235.

The effect of glenosphere size on functional outcome for reverse shoulder arthroplasty.

PURPOSE: Reverse shoulder arthroplasty (RSA) is an effective surgery for a variety of patients with difficult shoulder pathology. Since postsurgical outcomes are often variable, there has been great effort made to optimize the design and use of these implants. Previous studies demonstrated an association between increased glenosphere size and improved range of motion. The purpose of this study is to assess the relationship between glenosphere size, range of motion, and functional outcome scores. METHODS: This is a retrospective cohort study of 140 patients (148 shoulders) undergoing reverse shoulder arthroplasty. All patients were assessed pre- and postoperatively for range of motion, Constant score, ASES score, and Subjective Shoulder Value. Improvements in these variables were compared for patients treated with three different glenosphere sizes (36, 40, 42 mm). RESULTS: All groups had a mean improvement in range of motion and functional outcome scores, but there were no statistically significant differences between groups when controlling for preoperative differences. CONCLUSIONS: Our findings do not support a strong role for glenosphere size as a singular factor affecting range of motion or patient-reported outcome following RSA. These problems are most likely due to the multifactorial nature of shoulder dynamics. For this reason, assessing the effect a single surgical or biomechanical parameter on function has been challenging.