April Dawn Armstrong

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BACKGROUND Accurate analysis of osseous glenoid morphology is important in treating glenohumeral arthritis and instability. Two-dimensional computed tomography scans are used to evaluate glenoid alignment. Accuracy of this method is dependent on the angle of axial reconstruction in relation to the position of the scapula. The purpose of this study was to(More)
HYPOTHESIS Glenoid orientation likely plays an important role in shoulder mechanics and has been associated with glenohumeral instability, rotator cuff tears, and total shoulder arthroplasty outcome. Glenoid version and inclination measurements are widely used, but these measurements are 2-dimensional, and orientation of the central face must be inferred(More)
The use of shoulder ultrasound as an imaging modality has recently gained widespread attention; however, the ability of ultrasound to diagnose long head of the biceps tendon pathology accurately still remains unclear. The biceps tendons in 71 patients were prospectively evaluated by comparison of standard ultrasonographic and arthroscopic examinations.(More)
Patellar shift, tilt, and rotation were analyzed in 7 cadaveric knee specimens during simulated quadriceps loading, in the intact knee, and after implant reconstruction. Femoral component medialization, lateralization, and external rotation were also investigated. Relative motion of the patella with respect to the femur was measured using an electromagnetic(More)
The purpose of this study was to examine intratester, intertester, and interdevice reliability of range of motion measurements of the elbow and forearm. Elbow flexion and extension and forearm pronation and supination were measured on 38 subjects with elbow, forearm, or wrist disease by 5 testers. Standardized test methods and a randomized order of testing(More)
A principal challenge in creating accurate models of in situ scapulae is delineating bone from surrounding soft tissues. Computed tomography scans were obtained of both shoulders of 20 embalmed cadavers. Each shoulder was rescanned after repositioning of the cadavers to test for rescan reliability. After scans were complete, all scapulae were excised and(More)
The purpose of this study was to document the subscapularis healing rate by use of postoperative ultrasound and correlate healing to physical examination findings. We included 23 patients (30 shoulders), who underwent total shoulder arthroplasty in the study. The evaluation included a standard history and physical examination, ultrasound evaluation, and(More)
The elbow is a complex, highly constrained joint that provides critical range of motion to the upper extremity needed for performing the normal activities of daily living. The elbow is protected by a fortress of individual static and dynamic constraints that function together to provide stability. Knowing the identity and specific functions of each(More)
BACKGROUND Results of shoulder arthroplasty have been reported to be inferior with posterior glenoid wear and accompanying subluxation of the humeral head. The purpose of this study was to examine the effect of posterior glenoid wear on posterior subluxation of the humeral head. MATERIAL AND METHODS A custom loading device was used to simulate physiologic(More)
Rotator cuff injuries are a common clinical problem either as a result of overuse or aging. Biological approaches to tendon repair that involve use of scaffolding materials or cell-based approaches are currently being investigated. The cell-based approaches are focused on applying multipotent mesenchymal stem cells (MSCs) mostly harvested from bone marrow.(More)