Effect of glucosamine on intraocular pressure: a randomized clinical trial.

PurposeThe purpose of the study was to investigate ocular hypertensive effect of exogenous glucosamine in comparison with placebo in patients with osteoarthritis.Patients and methodsIn this double-masked randomized clinical trial, 88 patients with osteoarthritis were included. Forty-four patients were randomized into either glucosamine sulfate or the placebo group.Comprehensive ophthalmologic exam including intraocular pressure (IOP) at baseline, month 1, and 3 was performed. Ocular response analyzer parameters were also checked at baseline and month 3.ResultsThe mean IOP at the time of presentation was 12.4±2.7 mm Hg in glucosamine and 13±2.8 mm Hg in the placebo group (P=0.329). At month 1 the corresponding values were 12.6±2.4 and 12.9±2.4 mm Hg (P=0.868), and at 3 months follow-up were 13.5±2.3 and 13±2.7 mm Hg (P=0.002), respectively. About 34.1% in treatment and 12.5% in the placebo group had clinically significant (defined as ≥ 2 mm Hg) rise in IOP at final follow-up (P=0.023). Mean age in those with significant rise in IOP was 66 vs 57.7 years in patients with <2 mm Hg (P=0.034). The ORA parameters remained unchanged in both the groups during the course of study.ConclusionGlucosamine supplement therapy causes statistically significant rise of IOP, which is more pronounced in elderly patients. Clinical implication of this finding needs further evaluation.

A fast, accurate and closed-form method for pose recognition of an intramedullary nail using a tracked C-arm.

PURPOSE: The main challenge of intramedullary nail (IM-nail) fixation surgery is to achieve the X-ray shot in which the distal holes of the IM-nail appear as circles (desired view); screw insertion is then performed. Although C-arm X-ray devices are routinely used in IM-nail fixation procedures, the surgeons or radiation technologists (rad-techs) usually utilize them in a trial-and-error manner. This increases both radiation exposure and surgery time. This study addresses the problem by presenting a C-arm-based IM-nail pose recognition method. METHODS: The specific purpose of this study was to develop and validate an automated technique for identifying the current pose of the IM-nail relative to the C-arm. An accuracy assessment is performed to test the reliability of the navigation results. The algorithm starts with a sequential biplanar set of X-ray imagery (acquired from a tracked C-arm) of the distal part of an inserted IM-nail. The image-processing module then extracts features of interest, and a mathematical model incorporates them to calculate the six degree-of-freedom position and orientation parameters of the nail. RESULTS: Translational accuracy was demonstrated to be better than 0.5 mm, rotational accuracy for roll and pitch to be better than 2° and for yaw to be better than 2.5° depending on the separation angle. Computation time was less than 0.5 s. . CONCLUSION: An IM-nail distal locking navigation technique is introduced in this study that leads to more accurate and faster screw placement with a lower consumption of radiation dose and a minimum number of added steps to the operation.

Trapezoid supracondylar femoral extension osteotomy for knee flexion contractures in patients with haemophilia.

Flexion deformity of the haemophilic knee is a considerable cause of disability and may need to be managed surgically in severe cases. We have used a trapezoid supracondylar femoral extension osteotomy to correct severe knee flexion deformity. Nine severe haemophilic patients with contractures >30 degrees that were unresponsive to conservative measures underwent 11 trapezoid osteotomies. The angle of deformity was measured using anteroposterior and lateral knee X-ray films at maximum extension. Factor levels of 80-100% were achieved before the operation. A trapezoid osteotomy of the distal femur bone was performed using a lateral approach. The frontal plane angular deformity (if any) was corrected at the same time. The osteotomy site was fixed using an Arbeitsgemeinschaft für Osteo synthesefragen (AO) condylar blade plate. Following surgery, the knee was supported by a plaster splint at 20 degrees of flexion. Physiotherapy was started on third postoperative day and continued three times a week. There was no serious complication. The deformities were corrected in all of the patients and the mean range of motion increased form 68.6 degrees to 98.1 degrees . Bleeding episodes decreased in all four knees which had a bleeding score of 3 before surgery. Using the Orthopaedic Advisory Committee of the World Federation of Haemophilia scores, nine good and two fair results were obtained. All patients regained the ability to walk for both short and long distance without any aid, climb the stairs, bath, and use public transportation. Trapezoid supracondylar femoral extension osteotomy should be considered in the surgical management of severe haemophilic flexion deformity of the knee joint.