Platelet-rich plasma (PRP) has been demonstrated to benefit a variety of disciplines. But there exists heterogeneity in results obtained due to lack of standardization of the preparation protocols employed in them. We aim to identify and standardize a preparation protocol for PRP with maximum recovery of platelets to obtain reproducible results across studies. Blood samples were collected from 20 healthy volunteers. The double spin protocol of PRP preparation was analyzed for variables such as centrifugal acceleration, time, and volume of blood processed and final product utilized. The final PRP prepared was investigated for platelet recovery, concentration, integrity, and viability. We noted maximum platelet recovery (86-99%) with a mean concentration factor of 6-times baseline, with double centrifugation protocol at 100xg and 1600xg for 20 minutes each. We also noted that 10 ml of blood in a 15 ml tube was the ideal volume of blood to be processed to maximize platelet recovery. We demonstrated that the lower 1/3rd is the ideal volume to be utilized for clinical application. We did not note a loss of integrity or viability of the platelets in the final product from the above-said protocol. Preparation of PRP by the double spin protocol of 10 ml of blood at 100xg and 1600xg for 20 minutes each in a 15ml tube and using the lower 1/3rd of the final product demonstrated consistent high platelet recovery (86-99%) and concentration (6x) without disturbing the platelet integrity or viability

Silver nanoparticles (AgNPs) possess anti-inflammatory activities and have been widely deployed for promoting tissue repair. Here we explored the efficacy of AgNPs on functional recovery after spinal cord injury (SCI). Our data indicated that, in a SCI rat model, local AgNPs delivery could significantly recover locomotor function and exert neuroprotection through reducing of pro-inflammatory M1 survival. Furthermore, in comparison with Raw 264.7-derived M0 and M2, a higher level of AgNPs uptake and more pronounced cytotoxicity were detected in M1. RNA-seq analysis revealed the apoptotic genes in M1 were upregulated by AgNPs, whereas in M0 and M2, pro-apoptotic genes were downregulated and PI3k-Akt pathway signaling pathway was upregulated. Moreover, AgNPs treatment preferentially reduced cell viability of human monocyte-derived M1 comparing to M2, supporting its effect on M1 in human. Overall, our findings reveal AgNPs could suppress M1 activity and imply its therapeutic potential in promoting post-SCI motor recovery

The primary purpose of this longitudinal study was to examine the impact of physical and mental well-being on a successful return to work after cartilage or ligament knee injury. A secondary purpose was to examine the effectiveness of our program regarding ordering imaging (plain X-rays, US, MRI, CT scan), and the impact that costly investigations made in clinical management. Workers who had sustained a work-related knee injury and were assessed at the lower extremity specialty clinic of our hospital program were followed up until they were discharged. All patients completed the numeric pain rating scale (NPRS), the Lower Extremity Functional Scale (LEFS), and the Hospital Anxiety and Depression Scale (HADS) on the initial assessment and at final follow-up. We included 30 patients, mean age, 50(9), 11(37%) females, 19(63%) males. The most common mechanisms of injury were twisting (13, 45%) and falls (12, 41%). The knee injuries included 10 anterior collateral ligament (ACL), 3 posterior collateral ligament (PCL), 19 medical and lateral ligament injuries, and 22 meniscus injuries with some injuries overlapping. Ten patients (30%) underwent surgery (8 meniscectomy, two ligamentous repairs). Patients showed improvement in pain scores (p<0.0001) and the LEFS scores (p=0.004). Seventeen patients (57%) returned to full-time work and 11 (37%) were not working at the time of discharge with one patient performing part-time work, and one on re-training. Higher levels of pre (p=0.02) and post-treatment (p=0.03) depression and post-treatment anxiety (p=0.02) had a negative impact on a successful return to work. Most clients had proper investigations ordered by their family physicians in the community (24 plain x-rays, 11 US, and 21 MRI). Our team ordered only 6 plain x-rays and 6 new MRI. We found significant improvement in pain and disability in injured workers who received an expedited multidisciplinary care. Anxiety and depression were the most important predictors of poorer recovery and a less successful work status. The judicious use of costly imaging is expected to reduce the overall health care cost of an injury, while providing new important information such as adding a new diagnosis or changing the management

Prosthetic joint infection (PJI) is an uncommon but serious complication of hip replacement. Over 1,000 operations are performed annually in the United Kingdom for PJI following hip replacement, using either one- or two-stage revision arthroplasty. It is unclear which is preferred by patients and which has the best long-term outcome. This qualitative study aims to describe patient experiences of treatment and recovery following one- and two-stage revision arthroplasty for PJI within the context of a pragmatic randomised controlled trial comparing these two approaches. Semi-structured interviews were conducted with 32 patients undergoing one- or two-stage revision treatment for PJI as part of a UK multi-centre randomised controlled trial. Patients were recruited from 12 participating National Health Service (NHS) Orthopaedic Departments and were interviewed 2–4 months after their first revision surgery and again approximately 18 months later. Final sample size was justified on the basis of thematic saturation. All patients consented to the interview being audio-recorded, transcribed, anonymised and analysed using an inductive thematic approach. Ethical approval was provided by NRES Committee South-West Frenchay, 14/SW/116. Patients in both the one- and two-stage treatment groups described prolonged hospital stays, with burdensome antibiotics and brief physiotherapy treatment. However, following discharge home and during recovery, participants undergoing two-stage revision with an ‘empty hip' or with a spacer reported being physically restricted in almost every aspect of their daily life, resulting in inactivity and confinement to home. Mobility aids were not sufficiently available through the health service for these patients. A key difference is that those with a spacer reported more pain than those without. Approximately one year following their second-stage revision, participants described being more independent and active, but two directly attributed muscle weakness to the lengthy period without a hip and described resulting falls or dislocations that had complicated their recovery. In contrast, those undergoing one-stage revision and CUMARS appeared to be more alike, reporting better mobility, functionality and independence, although still limited. Participants in these groups also reported minimal or no pain following their revision. A key difference between CUMARS and one-stage revision was the uncertainty of whether a second operation was necessary, which participants described as “hanging over them”, while those in the two-stage empty hip or spacer group described a more positive anticipation of a second definitive operation as it marked an end to what was described as a detachment from life. Our findings highlight the differences between patient experiences of recovery following revision arthroplasty, and how this is influenced by the surgical approach and presence or lack of spacers. An understanding of lived experiences following one- and two-stage surgical interventions will complement knowledge about the clinical effectiveness of these different types of revision surgery

At our district general hospital in the southwest of England, around 694 total knee replacements (TKR) are performed annually. Since spring 2013 we have been using an enhanced recovery protocol for all TKR patients, yet we have neither assessed compliance with the protocol nor whether its implementation has made a discernible and measurable difference to the delivery of care in this patient population. Enhanced recovery after surgery (ERAS) protocols are multi-modal care pathways designed to aid recovery. They are based on best evidence and promote a multi-disciplinary approach which standardises care and encompasses nutrition, analgesia and early mobilisation throughout the pre, intra and postoperative phases of an inpatient stay. ERAS has been found to reduce length of stay (LOS), readmission rates and analgesic requirements following surgery. 1, 2, 3. Additionally, they have been shown to improve range of knee movement following TKR and improve mobility, patient satisfaction whilst reducing mortality and morbidity. 4, 5, 6. With these benefits in mind, we sought to investigate how well our trauma and orthopaedic department was complying with a local ERAS protocol and whether we could replicate the benefits seen within the literature. Following approval from our local audit office in September 2015 we generated a patient list of elective TKR patients under the same surgeon before and after the implementation of the ERAS protocol. Using discharge summaries and patient notes we extracted data for 39 patients operated on prior to the ERAS implementation between January 2011 and December 2012 and 27 patients following its introduction between January 2014 and September 2015. Data collected included length of stay, time to discharge from inpatient physiotherapy and use of analgesia and antiemetics. Alongside this we audited the compliance with all facets of the local ERAS protocol. There was no statistically significant difference between the 2 groups in terms of demographics or pre-operative morbidity. Overall compliance with the ERAS protocol was good but there was some variability, especially with intraoperative medication and type of anaesthesia which was likely due to individual patient factors. Compliance with postoperative analgesia was especially good with 93% of patients receiving all 4 suggested analgesics within the ERAS group. Length of stay (LOS) was significantly reduced by 0.5 days per patient (p value < 0.4). Overall compliance with the ERAS protocol was good but there was some variability, especially with intraoperative medication and type of anaesthesia, which was likely due to individual patient factors. Compliance with postoperative analgesia was especially good with 93% of patients receiving all suggested analgesics within the ERAS group. In terms of LOS, we found a statistically significant difference between the pre-ERAS and ERAS group of 0.5 days per patient. Within the context of our DGH, a 0.5 day reduction in LOS translates to around 350 bed days per year and a potential saving of GBP 105,000 (EUR 132,000) making this a clinically significant finding

Protocols for processing of tissue from arthroplasty infections vary and might affect the recovery of bacteria. We compared homogenization, bead beating and enzymatic disruption for recovery of live bacteria from tissue samples. Suspensions of Staphylococcus aureus and Escherichia coli were prepared as controls. Three samples were taken from each and the first was bead beaten, the second homogenized, and Proteinase K was added for 10 and 30 minutes to the third sample before culturing. In addition, artificially inoculated pork tissue and known infected human tissue samples were processed by either homogenization or bead beating prior to cultures and results were compared. Number of cycles of bead beating and homogenization and duration of Proteinase K treatment had significant effects. Bead beating for 2 and 4 cycles reduced the yield of S.aureus to 52% and 20% of control, and E.coli to 33% and 8%. Homogenization for 2 and 4 cycles reduced S.aureus to 86% and 65% of control, and E.coli to 90% and 87%. Proteinase K for 10 minutes and 30 minutes reduced the yield of S.aureus to 75% and 33% of control, and E.coli to 91% and 49% respectively. Inoculated Pork tissue showed a reduction in S.aureus recovery of 90% for bead beating compared to homogenization, and 80% in the case of E.coli. Bead beating of infected human tissue samples reduced the yield by 58% compared to homogenization. Bead-beating is a common recommended method of processing tissue from arthroplasty cases. However, even though it produces a homogeneous sample, it does so at the cost of significant loss of viable bacteria. Homogenization and 10 minutes of Proteinase K incubation are almost equivalent, but the homogenizer is preferred being more controllable and cheaper. This should help to define guidelines for diagnosing infections using tissue samples

Total knee arthroplasty (TKA) is becoming more prevalent as the average age of the general population increases and is generally considered to be a very effective and successful surgery. However, functional recovery post-surgery can often be less than optimal. Neuromuscular electrical stimulation (NMES) is a beneficial therapy proven to improve haemodynamics and muscle strength and may be of great benefit in improving functional recovery in the acute phase post-TKA. The objective of the study was to assess functional recovery in the period immediately following TKA and hospital discharge in response to a home-based NMES programme. Twenty-six TKA patients were randomized into a NMES stimulation or placebo-controlled group. All participants were given a research muscle stimulator to use at home post-discharge for 90 minutes per day over a period of 5 weeks. In the stimulation group, application of stimulation resulted in an electrically activated contraction of the soleus muscle. Patients in the placebo-controlled group received sensory stimulation only. Outcome measures were physical activity levels, joint range of motion and lower limb swelling, which were measured pre-surgery and on a weekly basis post-discharge up until the sixth post-surgical week. 90 minutes per day NMES stimulation significantly increased the Activity Time (P = 0.029 week 1 post-discharge) and the number of Stepping Bouts (P < 0.05 weeks 1 to 4 post-discharge) in the early post-discharge phase. While there was a trend towards a greater knee flexion with use of NMES, this did not reach statistical significance (P = 0.722). No effect of NMES was observed on swelling (P > 0.05 for all measures). Compliance to the NMES therapy was measured by an on-board SIM card in the NMES device, with a 95% and 94% time compliance rate for the stimulation and placebo-controlled groups respectively. The results of this study suggest that NMES may be very useful in improving functional recovery through increasing physical activity levels in the early post-TKA discharge phase. The results of this study warrant further investigation into the use of an optimized NMES protocol whereby improvements in knee range of motion and swelling may also be observed

The current study aims to find the role of Enhance Recovery Pathway (ERP) as a multidisciplinary approach aimed to expedite rapid recovery, reduce LOS, and minimize morbidity associated with Non Fusion Anterior Scoliosis Correction (NFASC) surgery. A retrospective analysis of 35 AIS patients who underwent NFASC with Lenke 1 and Lenke 5 curves with a minimum of 1 year of follow-up was done. Patient demographics, surgical details, postoperative analgesia, mobilization, length of stay (LOS), patient satisfaction survey score with respect to information and care, and 90 days complications were collected. The cohort included 34 females and 1 male with a mean age of 15.2 years at the time of surgery. There were 16 Lenke 1 and 19 Lenke 5 in the study. Mean preoperative major thoracic and thoracolumbar/lumbar Cobb's angle were 52˚±7.6˚ and 51˚±4.5˚ respectively. Average blood loss and surgical time were 102 ±6.4 ml and 168 ± 10.2 mins respectively. Average time to commencing solid food was 6.5±1.5 hrs. Average time to mobilization following surgery was 15.5± 4.3 hrs. The average duration to the stopping of the epidural was 42.5±3.5 hrs. The average dose of opioid consumption intraoperatively was 600.5±100.5 mcg of fentanyl i.v. and 12.5±4.5 mg morphine i.v. Postoperatively opioids were administered via an epidural catheter at a dose of 2 mg of morphine every 24 hours up to 2 days and an infusion of 2mcg/hr of fentanyl along with 0.12-0.15% ropivacaine. The average duration to transition to oral analgesia was 55.5±8.5 hrs .20 patients had urinary catheter and the average time to removal of the catheter was 17.5±1.4 hrs. 25 patients had a chest tube and the average time to remove of chest tube was 25.5±3.2 hrs. The average length of hospital stay was 3.1±0.5 days. No patient had postoperative ileus or requirement of blood transfusion or any other complications. No correlation was found between LOS and initial cobb angle. The application of ERP in AIS patients undergoing NFASC results in reduced LOS and indirectly the cost, reduced post-operative opioid use, and overall improve patient satisfaction score

Background. Predicting length of stay (LOS) is key to providing a cost effective and efficient arthroplasty service in an era of increasing financial constraint. Previous studies predicting LOS have not considered enhanced recovery protocols in elective hip and knee arthroplasty. Our study aims to identify patient variables in the pre and peri-operative period to predict increased LOS on patients enrolled into the standardised Chichester and Worthing Enhanced Recovery Programme (CWERP). Methods. All patients undergoing elective hip and knee arthroplasty were enrolled into CWERP using standardised anaesthetic, surgical and analgesic protocols. A data analyst prospectively collated data over 6months from anaesthetic charts and daily ward review from 663 patients between Dec 2012 and June 2013. An independent statistician undertook statistical analysis (program R, version 3.1.1). 80% of the 6months consecutive data (530 patients) were analysed, and predictive variables identified. These variables were tested against the remaining 20% of data (133 patients) predicting a LOS greater or less than our median of 4 days. Results. 663 patients were enrolled into CWERP over this period, 54% in hip arthroplasty. Statistical analysis was performed using Chi-squared test for association between actual and predicted (dichotomised) LOS being significant (p<0.0000000017). In the initial 80% (530 patients), this identified the following statistically significant variables in predicting LOS > 4 days: Age > 80 yrs, ASA 4, failure to mobilise on day of surgery, urinary catheterisation and need for blood transfusion. The statistical model when applied to the remaining 20% (133 patients) correctly categorised LOS in 101 (76%) of the patients. Conclusions. Identifying patients who fulfil our variables in the preoperative period affords better planning, maximising resources, bed efficiency and discharge planning. This also provides opportunities for financial remuneration for higher risk patients. Level of Evidence. 4

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 activity parameter. In-hospital recovery of activity is steep following a cascade of easy (ToF) to demanding (SST) tasks to quality (cadence). High standard deviations show that recovering activity is highly individual possibly demanding personalised support or goals (feedback). Quantitative parameters were all higher in the rapid versus the conventional discharge protocol indicating that fast activation is possible and safe. Equal cadence for both protocols shows that functional capacity cannot be easily accelerated. Pre-op activity is only a weak predictor of in-hospital recovery, indicating that surgical trauma affects patients similarly, but subjects may be identified for personalized physiotherapy or faster discharge. Reference values and correlations from this study can be used to optimize or shorten in-hospital rehabilitation via personalization, pre-hab, fast-track surgery or biofeedback

We reviewed renal function of 22 patients who had undergone total knee replacements using the enhanced recovery protocol (Caledonian technique) between August 2012 and November 2012 at a district general hospital in the west of Scotland. Pre-operative and post operative data were compared to determine if there was any change. We observed that 4 out of 22 (18%) of patients had a significant rise in creatinine, and 6 out of 22 (27%) had an abnormal eGFR. These findings were significant and were classed as (Acute Kidney Injury) AKI type 1, which should be treated actively. Subsequently, we collected data in the same way for 22 patients who underwent total knee replacements without using the enhanced recovery protocol. In this group, only one (5%) had a significant rise in creatinine and 2 (9%) had an abnormal eGFR. Significant difference is noted in the two groups. We conclude that the enhanced recovery protocol has some adverse effect on a patient's renal function. Our hypothesis is that this is due to restriction of fluids after surgery but a larger study is needed to find the cause and ways to avoid this

Introduction. Recovery of muscle strength following Total Knee Replacement (TKR) is variable, and can affect the resultant function of the patient. Satellite cells are undifferentiated myogenic precursors considered to be muscle stem cells that lie quiescently around the muscle fibre. These cells repair damaged fibres and have the potential to generate new muscle fibres. Therefore, theoretically, they could be associated with the variation in muscle recovery following surgery. We hypothesised that the recovery of muscle strength following knee replacement in a given patient would be influenced by the underlying number of satellite cells in that patient. Methods. 20 patients undergoing TKR were recruited from the waiting list of a single consultant. A muscle biopsy was taken at the time of surgery from the distal quadriceps. This was fixed in paraffin wax, and sections obtained. Satellite cells were identified with a primary mouse antibody for Pax7 - a cytoplasmic protein marker - and an immunofluorescent goat anti-mouse secondary. Slides were counterstained with DAPI to stain the myonuclei. The positive staining index (PSI) was calculated (number of satellite cells/total number of myonuclei x 100). Recovery of muscle (quadriceps) strength was assessed using the leg extensor power-rig (LegRig) pre-operatively, at 6 and 26 weeks post-operatively. Statistical analysis was performed using the Minitab version 15 software, the level of significance was set as p = 0.05. Results. 3 patients were unable to provide follow-up data. The number of satellite cells amongst individual patients in our cohort varied (PSI 3.07 to 11.35). Improvement in muscle power post-op also varied (0 to 70 W) between the 6 and 26 weeks assessment periods. This improvement in wattage generated between assessments reflected a relative improvement of between 0 and 60% in the strength to bodyweight ratio of these patients. The improvement in muscle power correlated with the satellite cell numbers (determined at the time of surgery). This was true for both absolute improvement in wattage generated (r = 0.54 p= 0.038) and also the improvement in strength to body weight ratio (r = 0.47 p = 0.06). Linear regression analysis demonstrated that the relative satellite cell number accounted for 30% of the improvement in muscle power. Discussion. We have for the first time demonstrated that the magnitude of improvement in muscle strength following TKR may be influenced by the patient's underlying pool of muscle satellite cells, with up to 30% of the variation of improvement in our cohort attributable to the satellite cell population

Background. While many studies have investigated long-term outcomes after lower limb arthroplasty, rather less is known about the trajectory of short-term outcomes in the first post-operative year. It is difficult for a surgeon to know when, in terms of disease severity, it is best to operate, or to make an accurate prediction of the patient pattern of post-operative recovery. We explored the trajectory of change in pain and function following primary hip and knee arthroplasty and the influence of pre-operative self-reported symptoms on post-operative improvements. Methods. A prospective UK cohort study of 164 patients undergoing primary hip (n=80) or knee (n=84) arthroplasty. WOMAC pain and function measures were collected pre-operatively and at 3 and 12 months post-operatively. Hip and knee arthroplasties were analysed separately, and patients were split into two groups: those with high or low symptoms pre-operatively. Multilevel regressions were used for each outcome (pain and function), and the trajectory of change (0–3 months and 3–12 months) charted. The study was approved by Southwest 4 Research Ethics Committee (09/H0102/72) and all patients provided informed, written consent. The authors have no competing interests to disclose. Results. Most improvement after hip arthroplasty occurred within the first 3 months post-operative. One year after surgery there was no difference in the outcomes between patients with high or low pain/function scores pre-operatively. Similarly, most improvement after knee arthroplasty occurred in the first 3 months. Improvement was greater for those patients with worse pre-operative functional disability and pain, although these patients never ‘caught-up’ with those with less severe pre-operative symptoms. Conclusions. Earlier intervention may be warranted for patients undergoing knee arthroplasty compared to hip arthroplasty to achieve the best post-operative patient-reported outcomes. Level of evidence. 2b, Individual cohort study

Summary. Collagen scaffolds loaded with mesenchymal stem cells accelerate neurological recovery in rat spinal hemisection. Objective. To investigate the implantation effects of the collagen scaffold (CS) combined with mesenchymal stem cells (MSCs) on the function recovery of spinal cord injury (SCI) with a lateral hemisection SCI SD rat model. Methods. MSCs were prepared from SD rat bone marrow. A T9 hemisection SCI SD rat model was developed with the removal of a 3mm left hemicord segment and a bundle of 2mm×2mm×3mm CS loaded with MSCs (5×10. 5. cell/20μl/bundle, CS/MSC) was implanted into hemi-transected gap. Four groups were randomly divided: the sham group without SCI, the control group with SCI, the CS-treated group with SCI and implanted CS, the CS/MSC-treated group with SCI and implanted CS/MSC. The neurological function recovery was evaluated by the 21-point Basso-Beattie-Bresnahan (BBB) scale and footprint analysis before and after SCI. The histological evaluation was performed at 4 and 8 weeks post injury by H&E staining and immunohistochemistry for neurofilament (NF), glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NES). Results. All the rats in the CS/MSC-treated group were alive while some rats were dead in the control and CS-treated groups. The BBB scores before the operation and at 1 week intervals after SCI for 8 weeks showed that the left hindlimbs function of CS/MSC-treated group restored faster and better than that of the control and CS-treated groups. In the ipsilateral hindlimb (left side), compared to the control and CS-treated group, the CS/MSC-treated group showed significant improvement in interlimb coordination by measuring the difference in stride length of fore- and hind-limb at 4 and 8 weeks, respectively. The base of support in CS/MSC-treated group was significantly reduced, and at 8 weeks, approximate equal to that of the sham group. The CS/MSC-treated group also showed smaller angle of rotation compared to the control and CS-treated groups. Histologically, compared to the control and CS-treated groups, spinal cord sections stained with H&E showed more tissue preservation in and around the injury site in the CS/MSC-treated group. Meanwhile, more NF-positive neural fibers, more density of NES staining and less GFAP positive astrocytes were observed in and around the injury site in the CS/MSC-treated group. Conclusions. These findings show that the combined application of CS and MSCs has an effect on neuroprotection and neurite guidance in the SCI rat model. It is well suggested the system would be an ideal approach to repair the spinal defect and to promote functional recovery after SCI

Physical outcome following total knee arthroplasty is variable. Satellite cells are undifferentiated myogenic precursors considered to be muscle stem cells. We hypothesised that; the recovery of muscle strength and physical function following knee arthroplasty would be influenced by the underlying number of muscle satellite cells. 16 patients provided a distal quadriceps muscle biopsy at time of surgery. Satellite cells were identified with a primary mouse antibody for Pax7 – a cytoplasmic protein marker, and the myonuclei with DAPI. Positive cells were identified on the basis of immunofluorescent staining in association with nuclear material, and confirmed by position under the basal lamina. Patient function was assessed using a validated physical assessment protocol, the Aggregated Locomotor Function (ALF) score, muscle strength assessed using the leg extensor power-rig, and clinical outcome assessed with the Oxford Knee Score (OKS) pre-operatively and at 1 year post operatively. Muscle satellite cell content varied amongst the patient group (Positive Staining Index 3.1 to 11.4). Satellite cell content at time of surgery correlated with change in outcomes between pre-operative and 1 year assessments in all assessed parameters (ALF, r = 0.31; muscle power, r = 49; OKS, r = 0.33). Regression analysis employing a forward stepwise selection technique employed satellite cell volume in models of pre-operative to 1 year change for all outcome parameters. Physical function (satellite cell content, patient age and pre-operative ALF score) adjusted R2 = 0.92; Muscle power (pre-operative power and satellite cell content) adjusted R2 = 0.38; Clinical outcome (pre-operative OKS and satellite cell content) adjusted R2 = 0.28. Muscle satellite cell content influences recovery of muscle power and physical function following total knee arthroplasty. Importantly it is also associated with change in clinical scores; suggesting it to be a biomarker for patient outcomes

INTRODUCTION. Motion analysis is routinely used in the clinical and research sectors to quantify joint biomechanics. It plays an important role in clinical assessments by aiding the physician to distinguish between primary movement abnormalities and any secondary compensatory mechanisms that may overshadow the cause of the problem. During a data collection session, a wealth of biomechanical data regarding joint and segment kinematics and kinetics are collected from patients performing daily activities. Objective classification can be used to automate a diagnosis from this data and has been used previously to analyse measurements of level gait [1]. It is of interest to assess the knee during stair-gait as this activity involves greater range of motion (ROM) of the lower limbs, larger forces and moments acting at the knee. AIM. The aim of the current study is to explore the use of an objective classifier [1] to characterise knee osteoarthritis (OA) and monitor functional recovery following a total knee replacement (TKR) using measurements from stair-gait. METHODS. Motion analysis techniques were used to quantify knee OA kinematics and kinetics during stair-gait for six patients with knee osteoarthritis (OA) and nine subjects without pathology (NP). One OA subject, forming a TKR sample, was also assessed at 4, 8 and 12 post-operatively. Each subject performed three trials of stair ascent and descent. 3D motion capture was performed using 8 Qualisys MCUs, capturing at 60Hz and a 1000Hz force plate (Bertec Corporation). Forces were measured from the first step of the staircase [2]. Independent t-tests were performed on biomechanical measures to compare the NP and OA cohorts (p<0.05). This identified the adaptations associated with knee OA. Principal components of salient kinematic and kinetic waveforms were used as inputs to train the classifier and subsequently characterise recovery of the TKR sample. RESULTS. The OA cohort adapted their stair-gait by reducing their peak: (i) external flexion moment in stance during both stair ascent and descent; (ii) medial ground reaction force (GRF) (iii) vertical GRF during stair descent and increasing their external adduction moment during stair ascent. The classifier was used to characterise knee function of the OA and NP subjects with 100% classification accuracy, defined using a Leave-one-out cross-validation. The TKR sample was classified as having dominant OA functional characteristics pre-operatively. At all subsequent measurements the subject was classified as having NP stair-gait characteristics. These changes correlated significantly with Knee Outcome Survey and Oxford Knee scores. CONCLUSION. Classification is a powerful tool for characterising data into two groups where a simplex plot provides a simple clinical interpretation of the results from a motion analysis assessment. This study demonstrates the use of objective classification to quantify NP, OA and TKR function from stair-gait. It also demonstrates its capability to monitor functional changes during a subject's recovery

Patients report similar or better pain and function before revision hip arthroplasty than before primary arthroplasty but poorer outcomes after revision surgery. The trajectory of post-operative recovery during the first 12 months and any differences by type of surgery have received little attention. We explored the trajectories of change in pain and function after revision hip arthroplasty to 12-months post-operatively and compared them with those observed after primary hip arthroplasty. We conducted a single-centre UK cohort study of patients undergoing primary (n = 80) or revision (n = 43) hip arthroplasty. WOMAC pain and function scores and 20-metres walking time were collected pre-operatively, at 3 and 12-months post-operatively. Multilevel regression models were used to chart and compare the trajectories of post-operative change (0–3 months and 3–12 months) between the types of surgery. Patients undergoing primary arthroplasty had a total hip replacement (n=74) or hip resurfacing (n=6). Osteoarthritis was the indication for surgery in 92% of primary cases. Patients undergoing revision arthroplasty had revision of a total hip arthroplasty (n=37), hemiarthroplasty (n=2) or hip resurfacing (n=4). The most common indication for revision arthroplasty was aseptic loosening (n=29); the remaining indications were pain (n=4), aseptic lymphocyte-dominated vasculitis-associated lesion (n=4) or other reasons (n=6). Primary (87%) and revision arthroplasties (98%) were mostly commonly performed via a posterior surgical approach. The improvements in pain and function following revision arthroplasty occurred within the first 3-months following operation (WOMAC-pain, p<0.0001; WOMAC-function, p<0.0001; timed 20-metres walk, p<0.0001) with no evidence of further change beyond this initial period (p>0.05). While the pattern of recovery after revision arthroplasty was similar to that observed after primary arthroplasty, improvements in the first 3-months were smaller after revision compared to primary arthroplasty (p<0.0001). Patients listed for revision surgery reported lower pre-operative pain levels (p=0.03) but similar post-operative levels (p=0.268) compared to those undergoing primary surgery. At 12-months post-operation patients who underwent a revision arthroplasty had not reached the same level of function achieved by those who underwent primary arthroplasty (WOMAC-function p=0.015; Time walk p=0.004). Patients undergoing revision hip arthroplasty should be informed that the majority of their improvement will occur in the first 3-months following surgery and that the expected improvement will be less marked than that experienced following primary surgery. More research is now required to 1.) identify whether specific in-patient and post-discharge rehabilitation tailored towards patients undergoing revision arthroplasty would improve or achieve equivalent outcomes to primary surgery and 2.) whether patients who are achieving limited improvements at 3-months post-operative would benefit from more intensive rehabilitation. This will become all the more important with the increasing volume of revision surgery and the high expectations of patients who aspire to a disease-free and active life

In recent years there has been growing interest in enhanced recovery regimes in lower limb arthroplasty due to potential clinical benefits of early mobilisation along with cost-savings. Following adoption of this regime in a district general hospital, it was observed that traditional dressings were a potential barrier to its success with ongoing wound problems in patients otherwise fit for discharge. The aim of this audit was to assess current wound care practice, implement a potentially improved regime and re-evaluate practice. A prospective clinical audit was performed over a three month period involving 100 patients undergoing hip or knee arthroplasty. Fifty patients with traditional dressings were evaluated prior to change in practice to a modern dressing (Aquacel™ Surgical). Fifty patients were then evaluated with the new dressing to complete the audit cycle. Clinical outcome measures included wear time, number of changes, blister rate and length of stay. Statistical comparisons were performed using Mann Whitney or Fisher's Exact test (statistical significance, p<0.05). Wear time for the traditional dressing (2 days) was significantly shorter than the modern dressing (7 days), p<0.001, and required more changes (0 vs. 3 days), p<0.001. 20% of patients developed blisters with the traditional dressing compared with 4% with the modern dressing (p=0.028). Length of stay was the same for the modern dressing (4 days) compared with the traditional dressing (4 days). However, in the modern group 75% of patients were discharged by day 4 whereas in the traditional group this took until day 6. This audit highlights the problems associated with traditional dressings with frequent early dressing changes, blistering and delayed discharge. These adverse outcomes can be minimised with a modern dressing specifically designed for the demands of lower limb arthroplasty. Units planning to implement enhanced recovery regimes should consider adopting this dressing to avoid compromising patient discharge

Post-operative regimes involving the use of intra-articular local anaesthetic infiltration may allow early mobilisation in patients undergoing total knee arthroplasty. Few studies have evaluated such regimes outside specialist arthroplasty units. We aimed to determine whether an enhanced recovery programme including the use of local anaesthetic administration could be adapted for use in a district general setting. Following introduction of this regime to our unit, 100 consecutive patients undergoing primary total knee arthroplasty were reviewed. 56 patients underwent a standard analgesic regime involving a general or spinal anaesthetic and oral analgesics post operatively (group1). 48 patients underwent the newly introduced regime, which included pre-operative counselling, peri-articular local anaesthetic infiltration at operation and intra-articular local anaesthetic top-up administration post-operatively for 24 hours (group 2). Length of stay, post-operative analgesic requirements, and range of knee motion post-operatively were compared. Median length of stay was less for patients in group 2 compared with those in group 1 (4 days compared to 5 days, p<0.05). Patients in group 2 required lower total doses of opiate analgesia post-operatively. 90% of patients in group 2 were ambulant on the first post operative day, compared with less than 25% of patients in group 1. Mean knee flexion on discharge was greater in patients in group 2 compared with those in group 1 (85 degrees compared with 75 degrees). No infective complications from intra-articular catheter placement were observed. However, technical difficulties were encountered during the introduction period, including loss of catheter placement, leakage of local anaesthetic and adaptation of nursing time for top-up anaesthetic administration. A rehabilitation regime involving local anaesthetic infiltration for total knee arthroplasty can successfully be adapted for use in a district general setting. Our results suggest if initial technical difficulties are overcome, this regime can provide effective postoperative analgesia, early mobilisation and reduced hospital stay

Summary Statement. In this study, we observed that MR16-1, an interleukin-6 inhibitor, recovered phosphatidylcholine containing docosahexaenoic acid at the injury site after spinal cord injury in mice model by using imaging mass spectrometry. Introduction. The current drugs for improving motor function of the limbs lost due to spinal cord injury (SCI) are ineffective. Development of new drugs for spinal cord injury is desired. MR16-1, an interleukin-6 inhibitor, is found to be effective in improving motor function after spinal cord injury in mice model. Thus, we examined the molecular mechanism in more detail. Therefore, the purpose of this study was to analyze the molecular changes in the spinal cord of the SCI mice treated with MR16-1 using imaging mass spectrometry. Methods. All experiments were performed according to the guidelines for animal experimentation and care and use of laboratory animals established by Hamamatsu University School of Medicine (Shizuoka, Japan). We used 36 adult female C57BL/6J mice for laminectomy and contusion injury of the spinal cord that were performed at the T10 level using the Infinite Horizon Impactor (IH Impactor, 60 kdyn; Muromachi, Tokyo, Japan). Immediately after SCI, mice were intraperitoneally injected with a single dose of MR16-1 (Chugai, Tokyo Japan) (100 µg/g body weight, MR16-1 group) or a single dose of phosphate-buffered saline (PBS) of the same volume (control group). Motor function of the hind limbs was evaluated using the Basso Mouse Scale (BMS), an open-field locomotor test in which the scores range from 0 points (scored for no ankle movement) to 9 points (scored for complete functional recovery). BMS scores were recorded at 1, 7, 14, 21, 28, 35, and 42 days after SCI. The spinal cord tissues were flash frozen and were sliced to a thickness of 8 µm using a cryostat (CM1950; Leica, Wetzler, Germany). Imaging mass spectrometry was used to visualise 12 molecular species of phosphatidylcholine (PC) from thin slices of the spinal cords obtained at 7 days post-SCI. Results. The contusive SCI immediately resulted in complete paralysis. The MR16-1–treated group showed a significant improvement in the BMS locomotor score compared with the control group at both 7 days and 42 days after SCI (1.4 vs 0.2 points and 4.0 vs 1.4 points, respectively). Phospholipids at 7 days after SCI showed unique distribution patterns. In particular, PCs containing docosahexaenoic acid (DHA) localised in the gray matter region was significantly higher in the MR16-1–treated group than in the control group, at 7 days post-SCI. Discussion. MR16-1 treatment showed to improve locomotor BMS score after 7 days of SCI compared with that observed in the control group. Spinal cord injury had induced inflammation; injury sites showed changes in the lipid content. We had previously reported that PC containing DHA mostly expressed in neuron cells decrease on injury sites. In this study, we observed that MR16-1 recovered PC containing DHA at the injury site. This may be associated with the recovery of motor function