King's College London, United Kingdom; 2 Biomechanics Group, Department ... don University Ethics Committee and Guy's Research Ethics Committees.
Abstracts / Manual Therapy 25 (2016) e33ee56
Implications: These results have implications for the prevention or management of conditions which advocate increased levels of physical activity (e.g. cardiovascular disease), since genetic factors might serve as an explanation for why some people respond better than others. Funding acknowledgements: None. Ethics approval: Ethics approval is not required. Disclosure of interest: None declared. Keywords: physical activity, response , twins Intergrating Research into practice OR-LL-014 LOWER LIMB KINEMATICS, MUSCLE ACTIVITY AND STRENGTH IN PARTICIPANTS WITH PATELLOFEMORAL PAIN SYNDROME L. Kedroff 1, *, A. Amis 2, D. Newham 3. 1 Division of Health and Social Care, King's College London, United Kingdom; 2 Biomechanics Group, Department of Mechanical Engineering, Imperial College London, United Kingdom; 3 Centre for Human and Aerospace Physiological Sciences, King's College London, London, United Kingdom * Corresponding author.
Background: Patellofemoral Pain Syndrome (PFPS) is one of the most prevalent knee disorders and can lead to persistent symptoms and restriction of activities. The aetiology is largely unproven but factors such as hip and knee muscle weakness, altered muscle activity and changes in kinematics have been implicated. Physiotherapy management focuses on exercises to address modifiable physical factors and research to identify the relevant factors will help inform clinical trials and rehabilitation programmes. Purpose: Four studies of healthy and PFPS participants were undertaken to compare; (i) hip and knee muscle activity and strength and (ii) foot and lower limb kinematics during stair negotiation, walking and squatting. Methods: For the 4 studies, convenience samples of male and female healthy controls (n ranged from 11e23) and participants with PFPS (n ¼ 11e25) were recruited. The participants with PFPS had symptoms for at least 6 weeks and no coexistent pathology. Other inclusion criteria were knee pain on at least 2 of the following activities: prolonged sitting, squatting, kneeling, ascending/descending stairs, or running. Light-emitting diodes were placed on the lower limb and foot and data were acquired using a 3-D movement analysis system (CODA mpx30). Measurements of joint motion were taken while the participants performed trials of walking, stair ascent and descent and singleand double-leg squats. Surface EMG from the vastus medialis obliquus, vastus lateralis, rectus femoris, hamstrings, gluteus maximus, and gluteus medius was recorded simultaneously, using pairs of active electrodes (Biopac). Hip and knee isometric strength was measured using an isokinetic (KinCom) or hand-held dynamometer (Nicholas Manual Muscle Tester). Using Mathcad software, the data were analysed and group differences in joint or body segment range and normalized EMG signal were assessed with either independent t or Mann-Whitney tests using SPSS software. Results: Weaker hip abductors, external rotators and extensors and knee extensors (p 0.04) were found in PFPS participants. Greater gluteus maximus and less hamstring EMG activity (p 0.01) were found during single leg squat descent in PFPS participants. No other group differences were noted in leg muscle activity and in hip and knee joint range during squatting and stair negotiation. Increased shank and rearfoot segment internal rotation and adduction of the mid- and forefoot segments (p 0.04) was found in PFPS participants during walking. Conclusion: PFPS participants have weak hip and knee muscles and demonstrate some kinematic changes, typically distal increases in limb internal rotation. Gluteus maximus and hamstrings muscle activity were altered during one task. However kinematic and muscle activity changes were variable and it is likely that for subgroups of participants, these changes are implicated in PFPS aetiology. Future work should explore whether kinematic variables are more important for subgroups
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and investigate the clinical relevance of these findings in rehabilitation trials. Implications: Physiotherapy management currently focuses on hip and knee muscle strengthening and some kinematic retraining. The studies undertaken provide evidence to support targeting strength deficits rather than kinematic retraining. Funding acknowledgements: Doctoral award (£1000) from the MACP Kingston NHS Hospital PhD funding (£12,000) Ethics approval: Ethical approval was obtained from King's College London University Ethics Committee and Guy's Research Ethics Committees. Disclosure of interest: None declared Keywords: Cross sectional study, Patella Intergrating Research into practice OR-LL-017 CLINICAL PREDICTORS OF RESPONSE TO EXERCISE & MANUAL THERAPY INTERVENTIONS FOR PATIENTS WITH HIP OSTEOARTHRITIS: A INDEPENDENT VALIDATION STUDY J.H. Abbott 1, *, G. Puts 2, Y. Pua 3, A. Wright 4, K. Bennell 5. 1 Centre for Musculoskeletal Outcomes Research, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; 2 Radboud University, Nijmegen, Netherlands; 3 Singapore General Hospital, Singapore, Singapore; 4 Highpoint University, Highpoint, United States; 5 University of Melbourne, Melbourne, Australia * Corresponding author.
Background: Exercise therapy is the recommended first-line intervention for patients with hip osteoarthritis (OA), and emerging evidence also recommends manual therapy. Previous authors have developed clinical prediction rules (CPRs) to predict the outcome from exercise and manual therapy interventions in patients with hip OA, however, the predictors identified in these models were different and have not been independently validated. Purpose: To assess the external validity of published preliminary CPR models, and to update those models, using data from the intervention and control arms from two randomized controlled trials (RCTs) of exercise and manual therapy in patients with hip OA. Methods: This was a parallel groups prognostic validity study. Data were obtained from 2 RCTs (#1: n ¼ 102, active intervention 49, sham control 53; and #2: n ¼ 93, active interventions 70, usual care control 23). Participants were classified as responders or non-responders using the OMERACT/OARSI criteria at 9e12 month follow-up. Logistic regression modelling was conducted. Log likelihood, pseudo-R2, area under-the-curve (AUC), Pearson goodness-of-fit test and the Hosmer and Lemeshow test were used to assess the performance of the models. Results: The external validity of the previously published models could not be confirmed. The updated models contained different predictors, namely: WOMAC overall 51; PCS overall 64; and the internal rotation range-of-motion 18.5. The final updated model had good fit with the intervention group data from RCT #1, resulting in an AUC of 0.92. All models showed poor fit with the sham group data from RCT #1. The updated model could not be shown to be valid in the independent data from RCT #2. Conclusion: Previously published preliminary models could not be validated on an independent dataset. Despite the promising results of the newly developed updated model, it too could not be validated on an independent dataset. Limitations include risk of overfitting of the prediction models due to a large number of potential predictor variables and relatively small number of responders per variable, and use of baseline WOMAC as a potential predictor, as it is correlated with the outcome of the OMERACT/OARSI criteria. Removal of baseline WOMAC from the model did not change the conclusions or interpretation. These analyses and results are consistent with concerns raised in the CPR literature that many preliminary models are not valid, but rather are chance findings that are not replicable in independent samples.
