Objective: To evaluate the results of 36unconstrained shoulder arthroplasties.Methods: In the series, 24 total and 12 hemiarthroplasties of the shoulders were performed with unconstrained shoulder prostheses in 29 patients who suffered from glenohumeral degenerative arthritis, rheumatoid arthritis, avascular necrosis and proximal fracture of humerus, respectively. Follow-up averaged 6.2years. All patients were evaluated pre- and post-operatively using the rating system of the Society of American Shoulder and Elbow Surgeons which assesses the severity of pain,strength of muscles around shoulder, stability, range of motion and functional activities of daily living. Radiolucent line and migration of prostheses were observed postoperatively on X-rays.Results: Postoperatively, the rate of pain relief was 91.3%, and active range of motion increased by 47° inforward flexion, 43° in abduction , 30° in external rotation,and 4 segments in internal rotation. Preoperatively the average points of 6 functional activities patients could perform was 0.8, and postoperatively 3.1. On postoperative X-ray, proximal migration of the humerus was seen in 8 shoulders, 6 of which had either a torn or absent rotator cuff. Radiolucent lines were seen around 1humeral component and 9 glenoid components. Onehumeral and 2 glenoid components loosened.Conclusions: These results suggest that unconstrained shoulder arthroplasty is a satisfactory and safe technique.

Related Analysis between the Interface Membrane and Loosening Prosthesis of Hip

Objective: To analyze the reason of loosening prosthesis by observing the interface membranes harvested during the hip revision operation. Methods: 28 specimens of interface membrane around the loosening prosthesis were harvested from 28 patients who underwent the revision of total hip replacement. All the specimens were observed by appearance, light microscope and scanning electronic microscope (SEM). Results: All the gap around the loosening prothesis were filled with different thickness of interface membranes. The color of the most interface membranes was madder red, and other one third of membranes was black. The thicker membrane was similar to scar connective tissue, the thinner was similar to fiber membrane. A large number of wear debris, macrophage and foreign-body giant cells were found under light microscope. With SEM observation, a large number of different diameter collagen fibra structures looked like scar tissue arranged disorderly in a great mass, different size of foreign particles and bone debris distributed unevenly, and the fibroblast distributed in the collagen fiber. Conclusion: Wear debris is relevant to inflammatory cells response around the interface membrane of the loosening prosthesis. The wear debris engulfed by macrophage stimulated the interface membrane to release bone resorption factors (such as TNF) which lead to osteolysis, and this was one of the most importment reasons of the prosthesis loosening.

Objective:To investigate the clinical value of total knee arthroplasty (TKA) on patients with advanced knee osteoarthritis. Methods:The clinical data and efficacy of 26 patients with advanced knee osteoarthritis (26 knees) who were given TKA in our department from June 2012 to May 2013 were retrospectively observed and analyzed. The knee function scores before operation and after follow up were evaluated according to American HSS scoring standard. Results:At the end of follow up, of the 26 patients, 18 were excellent, 6 were good and 2 were not bad in knee function and mobility without sense of pain, which was regarded to be associated with the poor enthusiasm in knee function training, and the total rate of excellent and good was 92.3%. Conclusion:TKA has signiifcant clinical value and favorable efifcacy on patients with advanced knee osteoarthritis.