Clinical and radiologic results after anatomic stemless shoulder prosthesis: a minimum 4-year follow-up.

BACKGROUND: Since the introduction of stemless anatomic shoulder arthroplasty, few midterm functional and radiographic results have been published. This article presents results of the Arthrex Eclipse prosthesis with a mean follow-up of 70 months. METHODS: We prospectively evaluated the outcome of 53 arthroplasties in 51 patients with a mean age of 65 years at the time of implantation with a minimum follow-up of 48 months. All patients were physically and radiologically examined, and the results documented by Constant-Murley and Disabilities of the Arm, Shoulder, and Hand (DASH) scores. RESULTS: Significant improvements from preoperative to last follow-up were documented in the Constant-Murley score (53.8%-83.5%, P < .001) and active range of motion (abduction 84°-108°, flexion 98°-125°, and external rotation 19°-41°). There was no significant difference between total and hemiarthroplasty. The mean DASH score was 28.3 points (95% confidence interval 20.1-35.2). Lowering of bone mineral density was observed in anteroposterior radiographs at the humeral component in 24.5% and at the glenoid component in 33.3%. The rate of complications was 15.7%. CONCLUSION: This study finds improvements in functional, radiographic, and subjective midterm results comparable to other accessible data for stemless and stemmed arthroplasty.

Magnetic resonance imaging in evaluation of tunnel diameters prior to revision ACL reconstruction: a comparison to computed tomography.

OBJECTIVE: Revision ACL reconstruction is becoming more frequent because of a 10% rate of re-ruptures and insufficiencies. Currently, computed tomography (CT) represents the gold standard in detecting and measuring the tunnels of the initial ACL reconstruction. The purpose of this study was to compare measurement results of CT and thin-sliced MRI sequences, which were modified to a high soft tissue-bone contrast. MATERIALS AND METHODS: Prior to an ACL revision surgery, 16 consecutive patients had an MRI in addition to the standard CT scan. A dedicated 0.25-T Esaote G-Scan (Esaote Biomedica, Cologne, Germany) with a Turbo 3D T1 sequence was used for MRI. Tunnel diameters were measured at 11 defined points of interest. For the statistical evaluation, the Mann-Whitney U test for connected samples was used. Inter- and intraobserver reliability was additionally calculated. RESULTS: All measured diameters showed significant to highly significant correlations between both diagnostic tools (r = 0.7-0.98). In addition, there was no significant difference (p > 0.5) between the two techniques. Almost all diameters showed nearly perfect intraobserver reliability (ICC 0.8-0.97). Interobserver reliability showed an ICC of 0.91/0.92 for only one diameter in MRI and CT. CONCLUSION: Prior to ACL revision surgery, bone tunnel measurements can be done using a 3D T1-MRI sequence in low-field MRI. MRI measurements show the same accuracy as CT scans. Preoperative radiation exposure in mainly young patients could be reduced. Also the costs of an additional CT scan could be saved.

1,25-dihydroxyvitamin D3 treatment delays cellular aging in human mesenchymal stem cells while maintaining their multipotent capacity.

1,25-dihydroxyvitamin D3 (1,25D3) was reported to induce premature organismal aging in fibroblast growth factor-23 (Fgf23) and klotho deficient mice, which is of main interest as 1,25D3 supplementation of its precursor cholecalciferol is used in basic osteoporosis treatment. We wanted to know if 1,25D3 is able to modulate aging processes on a cellular level in human mesenchymal stem cells (hMSC). Effects of 100 nM 1,25D3 on hMSC were analyzed by cell proliferation and apoptosis assay, ß-galactosidase staining, VDR and surface marker immunocytochemistry, RT-PCR of 1,25D3-responsive, quiescence- and replicative senescence-associated genes. 1,25D3 treatment significantly inhibited hMSC proliferation and apoptosis after 72 h and delayed the development of replicative senescence in long-term cultures according to ß-galactosidase staining and P16 expression. Cell morphology changed from a fibroblast like appearance to broad and rounded shapes. Long term treatment did not induce lineage commitment in terms of osteogenic pathways but maintained their clonogenic capacity, their surface marker characteristics (expression of CD73, CD90, CD105) and their multipotency to develop towards the chondrogenic, adipogenic and osteogenic pathways. In conclusion, 1,25D3 delays replicative senescence in primary hMSC while the pro-aging effects seen in mouse models might mainly be due to elevated systemic phosphate levels, which propagate organismal aging.