Abstract:The failure of a proximal humerus internal locking system (PHILOS) used in a pantalar arthrodesis was investigated in this paper. PHILOS constructs are hybrids using locking and non-locking screws. Both the plate and the screws used in the fusion were obtained for analysis. However, only the plate failure analysis is reported in this paper. The implant had failed in several pieces. Optical and scanning electron microscopic analyses were performed to characterize the failure mode(s) and fracture surface. The chemical composition and mechanical properties of the plate were determined and compared to controlling specifications to manufacture the devices. We found that equivalent tensile strength exceeded at the locations of high stress, axial, and angular displacement and matched the specification at the regions of lower stress/displacement. Such a region-wise change in mechanical properties with in vivo utilization has not been reported in the literature. Evidence of inclusions was qualitatively determined for the stainless steel 316L plate failing the specifications. Pitting corrosion, scratches, discoloration and debris were present on the plate. Fracture surface showed (1) multi-site corrosion damage within the screw holes forming a 45 • maximum shear force line for crack-linking, and (2) crack propagation perpendicular to the crack forming origin that may have formed due to the presence of inclusions. Fracture features such as beach marks and striations indicating that corrosion may have initiated the crack(s), which grew by fatigue over a period of time.In conclusion, the most likely mechanism of failure for the device was due to corrosion fatigue and lack of bony in-growth on the screws that may have caused loosening of the device causing deformity and pre-mature failure.

Background: Triceps tendon ruptures are rare orthopaedic injuries that almost always require surgical repair. This study tests the biomechanical properties of an original anchorless double-row triceps repair against a previously reported knotless double-row repair.

No abstract

The use of tranexamic acid (TXA) in total knee arthroplasty (TKA) has become common practice. Recent literature has demonstrated a reduction in postoperative knee swelling and drain output while using TXA. Our purpose is to analyze the range of motion (ROM) following TKA in patients who received TXA compared with a control group. We hypothesize that patients treated with TXA will have improved early postoperative ROM when compared with controls. A retrospective chart review was performed for patients who underwent TKA from 2010 to 2012 performed by a single orthopaedic surgeon. Patients were stratified into three cohorts by route of TXA administration including intravenous (IV), topical, and a control group. Dependent variables analyzed included extension, flexion, and total arc ROM on each postoperative day (POD), average ROM across all three postoperative days, as well as pre-to-postoperative differences in ROM. Demographic data were recorded for each patient. A total of 174 patients were included for analysis, 75 controls and 99 receiving TXA. A significant difference was found between the treatment groups and the control for all variables (for each, ≤ 0.002). There were no significant differences in ROM between the IV and topical TXA treatment groups (for each, ≥ 0.558). A multivariate analysis demonstrated no significant difference between the groups in complication rate or demographic variables. The use of TXA may improve early postoperative ROM following TKA.

No abstract