Eliminating pain and restoring physical activity are the main goals of total hip arthroplasty (THA). Despite the high relevance of activity as a rehabilitation goal of and criterion for discharge, in-hospital activity between operation and discharge has hardly been investigated in orthopaedic patients. Therefore, the aim of this study was to a) measure for reference the level of in-hospital physical activity in patient undergoing a current rapid discharge protocol, b) compare these values to a conventional discharge protocol and c) test correlations with pre-operative activities and self-reported outcomes for possible predictors for rapid recovery and discharge. Patients (n=19, M:F: 5:14, age 65 ±5.7 years) with osteoarthritis treated with an elective primary THA underwent a rapid recovery protocol with discharge on day 3 after surgery (day 0). Physical activity was measured using a 3D accelerometer (64×25×13mm, 18g) worn on laterally on the unaffected upper leg. The signal was analysed using self-developed, validated algorithms (Matlab) calculating: Time on Feet (ToF), steps, sit-stand-transfers (SST), mean cadence (steps/min), walking bouts, longest walk (steps). For the in-hospital period (am: ca. 8–13h; pm: ca. 13–20h) activity was calculated for day 1 (D1) and 2 (D2). Pre-operative activity at home was reported as the daily averages of a 4-day period. Patient self-report included the HOOS, SQUASH (activity) and Forgotten Joint Score (FJS) questionnaires. In-hospital activity of this protocol was compared to previously collected data of an older (2011), standard conventional discharge protocol (day 4/5, n=40, age 71 ±7 years, M:F 16:24). All activity parameters increased continuously between in-hospital days and subsequent am and pm periods. E.g. Time-on-feet increased most steeply and tripled from 21.6 ±14.4min at D1am to 62.6 ±33.4min at D2pm. Mean Steps increased almost as steep from 252 to 655 respectively. SST doubled from 4.9 to 10.5. All these values were sign. higher (+63 to 649%) than the conventional protocol data. Cadence as a qualitative measure only increased slowly (+22%) (34.8 to 42.3steps/min) equalling conventional protocol values. The longest walking bout did not increase during the in-hospital period. Gender, age and BMI had no influence on in-hospital activity. High pre-op activity (ToF, steps) was a predictor for high in-hospital activity for steps and SST's at D2pm (R=0.508 to R=0.723). Pre-op self-report was no predictor for any
Osteocytes are terminally differentiated long-lived cells and account for greater than 95% of the bone cell population. It has been established that osteocytes are connected through their highly developed dendritic network, which is necessary for the maintenance of optimal bone homeostasis. However, little is known on how osteocytes use the network to coordinate their cellular function and communication that requires energy and protein turnover. Here using super-resolution confocal imaging on both live and fixed osteocytes, we demonstrated conclusively that mitochondria are widely distributed and dynamically shared between osteocytes. Using confocal live cell imaging analysis we showed that inhibiting the contact between mitochondria and endoplasmic reticulum (ER) by the knockdown of MFN2 in osteocytes impedes the transfer of mitochondria suggesting the involvement of ER contact with mitochondria in the transfer process. Moreover, we showed that transport of mitochondria between osteocytes within the network enables rescue of osteocytes with dysfunction of mitochondria. Using the 3D tetraculture system with confocal imaging, we identify the transfer of mitochondria from healthy osteocytes enables
Short intense electrical pulses transiently increase the permeability of the cell membrane, an effect known as electroporation. This can be combined with antiblastic drugs for ablation of tumours of the skin and subcutaneous tissue. The aim of this study was to test the efficacy of electroporation when applied to bone and to understand whether the presence of mineralised trabeculae would affect the capability of the electric field to porate the membrane of bone cells. Different levels of electrical field were applied to the femoral bone of rabbits. The field distribution and modelling were simulated by computer. Specimens of bone from treated and control rabbits were obtained for histology, histomorphometry and biomechanical testing. After seven days, the area of ablation had increased in line with the number of pulses and/or with the amplitude of the electrical field applied. The osteogenic activity in the ablated area had recovered by 30 days. Biomechanical testing showed structural integrity of the bone at both times. Electroporation using the appropriate combination of voltage and pulses induced ablation of bone cells without affecting the
Following acute ACL rupture patients are routinely referred for rehabilitation but the timing and level of functional recovery related to rehabilitation outcome are poorly defined. The primary aim of this study was to measure functional recovery following acute ACL rupture in the clinical setting using a two dimensional movement analysis system. A longitudinal research design was used; we aimed for three clinical movement analysis sessions over the course of rehabilitation. One hundred and fifteen patients were recruited. Sixty three uninjured matched controls were recorded once performing all the functional activities; walking, jogging, distance hop and run and stop. Participants were filmed in the sagittal plane using a digital camcorder to extract kinematic data. Average recovery over time was modelled using a least squares third order polynomial. The secondary aim was to define the outcome measures and treatment goals used in ACL rehabilitation by specialist knee physiotherapists. A questionnaire was distributed to 300 hospitals across the UK. From the 44 responses insight was obtained about parameters physiotherapists use to plan treatment and evaluate recovery. Repeated movement analysis showed that gait velocity took on average 85 days to recover to within the normal limits of uninjured controls. Jogging velocity took 30 days; Hop distance took 55 days for the non-injured leg and 100 days for the injured leg; Knee range during the landing phase of run and stop took 80 days to recover but demonstrated some deterioration. The questionnaire identified that specialist knee physiotherapists use 60 different outcome measures and 34 rehabilitation treatment goals, which can be sub-divided into patient reported (PR), functional activities (A) and impairments (I). The percentage usage by physiotherapists for each category of outcome measure were 55.8% (A), 62.8% (I) to 67.4% (PR) and for treatment goals 55.8% (PR), 69.8% (A) to 81.4% (I). Hopping is the most frequently evaluated functional activity but there are large differences in its utilisation. The application of functional goals and outcome measures in rehabilitation is not universal with specialist physiotherapists generally adopting an impairment approach. Repeated movement analysis in the clinical setting provided objective data on the