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Background: Pelvic osteotomies are performed to prevent the progression of osteoarthritis and its associated pain due to adult hip dysplasia, particularly for young patients with no or low-grade osteoarthritis. No data are available concerning levels of sporting activity before and after triple pelvic osteotomy (TPO). Therefore, the aim of this study was to provide comprehensive data on levels of sporting activity and the subjective outcome of patients after this complex operation., Hypothesis: Patients can return to a higher level of sports activity after TPO compared with their preoperative level., Study Design: Case series; Level of evidence, 4., Methods: Between 2003 and 2011, a total of 116 triple pelvic osteotomies were performed at a single institution; the Tönnis and Kalchschmidt technique was used on 91 patients. After exclusion criteria for this study were applied, 77 patients remained (59 females and 18 males); the mean ± SD age at operation was 26 ± 3.9 years. To study outcomes, patients were asked to complete both the Harris hip score (HHS) and the Hip disability and Osteoarthritis Outcome Score (HOOS) preoperatively and at postoperative follow-up. Their level of activity was determined according to the University of California, Los Angeles (UCLA) activity score. Patients rated their hip movement and overall satisfaction preoperatively and at postoperative follow-up using a visual analog scale for sporting activity, physical fitness level, and level of pain experienced while performing their sport., Results: The mean ± SD follow-up time was 6.2 ± 1.4 years. The mean HHS changed significantly from 63.3 ± 15.6 preoperatively to 90.1 ± 10.8 at follow-up (P < .001), and the mean HOOS changed significantly from 52.9 ± 20.1 to 82 ± 17.1 at follow-up (P < .001). The mean UCLA activity score changed significantly from 4.8 ± 2.1 to 7.7 ± 1.4 at follow-up (P < .001)., Conclusion: Patients achieved a higher level of sports activity postoperatively. The postoperative level of participation in sports was superior, with a shift from low- to high-impact activities., (© 2014 The Author(s).)

Degradable magnesium alloys are promising biomaterials for orthopedic applications. The aim of this study was to evaluate the potential effects on both the synovial membrane (synovialis) and the synovial fluid (synovia) of the degradation products of a MgYREZr-pin implanted in the intercondylar femoral notch in a rabbit model. Thirty-six animals were randomized into two groups (MgYREZr or Ti6Al4V alloy) of 18 animals each. Each group was then divided into three subgroups with implantation periods of 1, 4, and 12 weeks, with six animals in each subgroup. The initial inflammatory reaction caused by the surgical trauma declined after 12 weeks of implantation, and elucidated a progressive recovery of the synovial membrane. Compared with control Ti6Al4V pins, there were no significant differences between the groups. However, after 12 weeks, recovery of the synovial membrane was more advanced in the titanium group, in which 92% showed no signs of synovitis, than in the magnesium group. A cytotoxicity test with L929 cells and human osteoblasts (HOB) was also conducted, according to EN ISO 10993-5/12, and no toxic leachable products were observed after 24 h of incubation. In conclusion, the MgYREZr alloy seems to be a suitable material for intra-articular degradable implants., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

In this in vitro study, magnesium plates of ZEK100 and MgCa0.8 alloy similar to common titanium alloy osteosynthesis plates were investigated as degradable biomedical materials with a focus on primary stability. Immersion tests were performed in Hank's Balanced Salt Solution at 37. The bending strength of the samples was determined using the four-point bending test according to ISO 9585:1990. The initial strength of the noncorroded ZEK100 plate was 11% greater than that of the MgCa0.8 plate; both were approximately 65% weaker than a titanium plate. The bending strength was determined after 48 and 96 h of immersion in Hank's Balanced Salt Solution; both magnesium alloys decreased by approximately 7% after immersion for 96 h. The degradation rate and the Mg(2+) release of ZEK100 were lower than those of MgCa0.8. Strong pitting and filiform corrosion were observed in the MgCa0.8 samples after 96 h of immersion. The surface of the ZEK100 plates exhibited only small areas of filiform corrosion. The results of this in vitro study indicate that the ZEK100 alloy may be more suitable for biomedical applications.

Biodegradable magnesium-based implants are currently being developed for use in orthopedic applications. The aim of this study was to investigate the acute, subacute, and chronic local effects on bone tissue as well as the systemic reactions to a magnesium-based (MgYREZr-alloy) screw containing rare earth elements. The upper part of the screw was implanted into the marrow cavity of the left femora of 15 adult rabbits (New Zealand White), and animals were euthanized 1 week, 12 weeks, and 52 weeks postoperatively. Blood samples were analyzed at set times, and radiographic examinations were performed to evaluate gas formation. There were no significant increased changes in blood values compared to normal levels. Histological examination revealed moderate bone formation with direct implant contact without a fibrous capsule. Histopathological evaluation of lung, liver, intestine, kidneys, pancreas, and spleen tissue samples showed no abnormalities. In summary, our data indicate that these magnesium-based screws containing rare earth elements have good biocompatibility and osteoconductivity without acute, subacute, or chronic toxicity.

Background: The most effective surgical treatment for traumatic posterior shoulder instability remains unclear., Hypothesis: An arthroscopic posterior Bankart repair is as effective as an open posterior bone block-capsulorrhaphy procedure regarding the restoration of humeral displacement with posterior and inferior forces., Study Design: Controlled laboratory study., Methods: Biomechanical testing of 16 human shoulders was performed in 3 testing conditions: after ventilation (intact joint), after creation of a posteroinferior Bankart lesion with an additional cut of the posterior band of the inferior glenohumeral ligament, and after surgical shoulder stabilization. The shoulder stabilization was performed either by an open posterior bone block procedure and glenoid-based T-capsulorrhaphy or by an arthroscopic Bankart repair. Testing was performed in 2 positions-the sulcus test position and the jerk test position-with a passive humerus load of 50 N applied in the posterior, posteroinferior, and inferior directions., Results: After the arthroscopic repair, there was no significant difference between the translation and the intact state for all tested directions. The bone block repair-capsulorrhaphy caused a significant decrease of posterior translation (sulcus test and jerk test positions) and posteroinferior translation (jerk test position). But the resulting posterior and posteroinferior translation was even significantly lower than the translation measured for the intact joints. However, the reduction of inferior translation, compared with that of the defect condition, was not significant after the bone block repair (sulcus test and jerk test positions). Compared with that of the intact joint, inferior translation after the bone block repair was significantly higher., Conclusion: The posterior bone block repair-capsulorrhaphy overcorrects posterior translation and does not effectively restore inferior stability, whereas the arthroscopic posterior Bankart repair restores posterior and inferior laxity of the intact joint., Clinical Relevance: An arthroscopic posterior capsulolabral repair more precisely restores posterior and inferior glenohumeral joint laxity and is therefore recommended as the first choice of treatment.

Background: This study was conducted to evaluate the treatment of severe foot deformities using the Taylor spatial frame., Materials and Methods: The treatment of seven patients with nine severe foot deformities was reviewed. The mean age of the patients at surgery was 16 years with a mean followup of 21.5 months. The following parameters were assessed: etiology of deformity, date of surgery, surgical procedure, age at surgery, previous surgical or conservative treatments, preoperative symptoms, preoperative and postoperative deformity and affected side, complications during correction, duration of TSF, duration of hospital stay, occurrence of secondary osteoarthritis, recurrence of deformity, surgical revisions or subsequent surgeries. The pre- and postoperative deformity was assessed clinically. The final outcome was categorized as good, fair, or poor., Results: The results were good in eight feet and poor in one foot. Early complications included pin tract infection, temporary hypoesthesia and temporary shortening of the tendon of the flexor digitorum longus. Recurrence of deformity occurred in no patient. One patient required a subtalar arthrodesis for symptomatic, secondary osteoarthritis in one foot., Conclusion: The present study showed that TSF is a viable solution to correct severe foot deformities but we believe a surgeon should be aware of the possible complications.

The effect of a medially based anterior capsular shift on translational and rotational range of motion and posterior capsular strain was investigated in an in vitro model. Six cadaveric shoulders were tested in a robot-assisted shoulder simulator. Translational and rotational range of motion were reduced by the capsular shift, particularly with the shoulder at higher elevation angles. At 60 degrees of elevation, anterior translation was decreased 1.9 +/- 2.9 mm, and posterior translation was decreased 2.3 +/- 6.2 mm. External rotation was decreased 11.5 degrees +/- 10.2 degrees, and internal rotation was decreased 8.9 degrees + 5.7 degrees. Posterior capsular strain change was dependent on elevation angle. At 30 degrees of elevation, strain tended to increase 5.0% +/- 7.3% in the inferior aspect and 2.9% +/- 2.6% in the superior aspect, with no change detected in the medial aspect. At 60 degrees of elevation, strain increased 6.6% +/- 8.0%, 3.2% +/- 2.6%, and 4.4% +/- 3.5% in the inferior, middle, and superior aspects, respectively. Our results support the use of the medially based anterior shift for shoulders with anterior-inferior instability or multidirectional instability with posterior involvement.