II.

These findings may be of relevance for future clinical treatment of patellar tendon ruptures. Randomized controlled clinical trials comparing suture anchors to transosseous suture repair are desirable.

Not applicable, controlled laboratory human cadaveric study.

Purpose This study analysed the effects of upright weight bearing and the knee flexion angle on patellofemoral indices, determined using magnetic resonance imaging (MRI), in patients with patellofemoral instability (PI). Methods Healthy volunteers (control group, n = 9) and PI patients (PI group, n = 16) were scanned in an open‐configuration MRI scanner during upright weight bearing and supine non‐weight bearing positions at full extension (0° flexion) and at 15°, 30°, and 45° flexion. Patellofemoral indices included the Insall–Salvati Index, Caton–Deschamp Index, and Patellotrochlear Index (PTI) to determine patellar height and the patellar tilt angle (PTA), bisect offset (BO), and the tibial tubercle–trochlear groove (TT–TG) distance to assess patellar rotation and translation with respect to the femur and alignment of the extensor mechanism. Results A significant interaction effect of weight bearing by flexion angle was observed for the PTI, PTA, and BO for subjects with PI. At full extension, post hoc pairwise comparisons revealed a significant effect of weight bearing on the indices, with increased patellar height and increased PTA and BO in the PI group. Except for the BO, no such changes were seen in the control group. Independent of weight bearing, flexing the knee caused the PTA, BO, and TT–TG distance to be significantly reduced. Conclusions Upright weight bearing and the knee flexion angle affected patellofemoral MRI indices in PI patients, with significantly increased values at full extension. The observations of this study provide a caution to be considered by professionals when treating PI patients. These patients should be evaluated clinically and radiographically at full extension and various flexion angles in context with quadriceps engagement. Level of evidence Explorative case–control study, Level III.

This is the first comprehensive prospective clinical study to our knowledge investigating the significance of a combined biomarker approach in differentiating between aseptic prosthesis loosening and low-grade joint infection. CRP plus IL-6 seems to be the most helpful combination for preoperative discrimination of aseptic loosening vs low-grade joint infection.

BackgroundGoogle Glass is a promising premarket device that includes an optical head-mounted display. Several proof of concept reports exist, but there is little scientific evidence regarding its use in a medical setting.ObjectiveThe objective of this study was to empirically determine the feasibility of deploying Glass in a forensics setting.MethodsGlass was used in combination with a self-developed app that allowed for hands-free operation during autopsy and postmortem examinations of 4 decedents performed by 2 physicians. A digital single-lens reflex (DSLR) camera was used for image comparison. In addition, 6 forensic examiners (3 male, 3 female; age range 23-48 years, age mean 32.8 years, SD 9.6; mean work experience 6.2 years, SD 8.5) were asked to evaluate 159 images for image quality on a 5-point Likert scale, specifically color discrimination, brightness, sharpness, and their satisfaction with the acquired region of interest. Statistical evaluations were performed to determine how Glass compares with conventionally acquired digital images.ResultsAll images received good (median 4) and very good ratings (median 5) for all 4 categories. Autopsy images taken by Glass (n=32) received significantly lower ratings than those acquired by DSLR camera (n=17) (region of interest: z=–5.154, P<.001; sharpness: z=–7.898, P<.001; color: z=–4.407, P<.001, brightness: z=–3.187, P=.001). For 110 images of postmortem examinations (Glass: n=54, DSLR camera: n=56), ratings for region of interest (z=–8.390, P<.001) and brightness (z=–540, P=.007) were significantly lower. For interrater reliability, intraclass correlation (ICC) values were good for autopsy (ICC=.723, 95% CI .667-.771, P<.001) and postmortem examination (ICC=.758, 95% CI .727-.787, P<.001). Postmortem examinations performed using Glass took 42.6 seconds longer than those done with the DSLR camera (z=–2.100, P=.04 using Wilcoxon signed rank test). The battery charge of Glass quickly decreased; an average 5.5% (SD 1.85) of its battery capacity was spent per postmortem examination (0.81% per minute or 0.79% per picture).ConclusionsGlass was efficient for acquiring images for documentation in forensic medicine, but the image quality was inferior compared to a DSLR camera. Images taken with Glass received significantly lower ratings for all 4 categories in an autopsy setting and for region of interest and brightness in postmortem examination. The effort necessary for achieving the objectives was higher when using the device compared to the DSLR camera thus extending the postmortem examination duration. Its relative high power consumption and low battery capacity is also a disadvantage. At the current stage of development, Glass may be an adequate tool for education. For deployment in clinical care, issues such as hygiene, data protection, and privacy need to be addressed and are currently limiting chances for professional use.

A number of short stems for total hip arthroplasty have been introduced during the last decade. We describe our experience with the NANOS prosthesis (Smith and Nephew, Marl, Germany). The potential increase of bone mass around a femoral short stem using bone densitometry may be an indicator for secondary ingrowth. We report the outcome of 72 NANOS short stems in 65 patients between March 2003 and October 2007. The mean follow-up was 5.2±0.7 years and the mean age of the patients was 63±8.3 years. Along with demographic data and co-morbidities, the Harris Hip Score, the Merle d'Aubigné mobility score, and a patient-centred questionnaire were evaluated pre-operatively and during follow-up. The Mean Harris Hip Score increased from 47.3±12.2 pre-operatively to 97.6±0.6 at the final follow-up. The Merle d'Aubigné mobility score increased from 7.6±1.4 pre-operatively to 11.8±0.3 at the final follow-up. None of the 72 stems were revised, providing a survival rate of 100%. Radiolucent lines were visible rasiographically in two patients during follow-up. The NANOS short stem demonstrated a satisfactory outcome at mid term follow-up. The clinical and radiological results support to the principle of metaphyseal anchorage of a short stem prosthesis. Long term evaluation will be of interest to determine if these encouraging trends are reflected by prolonged survivorship.

No abstract