G.H. Gonçalves

Kinematic alterations of the lower limbs and pelvis during an ascending stairs task are associated with the degree of knee osteoarthritis severity

BACKGROUND Individuals with knee osteoarthritis (OA) generally demonstrate great difficulty in ascending stairs. The strategies and compensations used by these individuals in stair activities have not been fully established. The purpose of this study was to investigate the joint kinematics of the pelvis, hip, knee and ankle throughout the gait cycle, in the sagittal and frontal planes, in individuals with mild and moderate knee OA, during an ascending stairs task. METHODS Thirty-one individuals with knee OA and 19 controls were subjected to clinical and radiographic analysis, divided into three groups: control, mild knee OA, and moderate knee OA. Participants answered a self-reported questionnaire, carried out performance-based tests, and their kinematic data were recorded during an ascending stairs task using an eight-camera Qualisys 3D-Motion analysis system. RESULTS The individuals with moderate degrees of knee OA demonstrated kinematic alterations in the pelvis, hip, knee, and ankle in the sagittal plane. The individuals with mild degrees of knee OA demonstrated kinematic alterations of the hip in the frontal plane, and kinematic alterations of the ankle in the sagittal plane. CONCLUSIONS The ascending stairs task allowed verification of meaningful information regarding gait strategies used by individuals with mild and moderate knee OA. The strategies of these two groups of individuals are different for this task, although more pronounced in individuals with moderate knee OA. The findings should be taken into account in the development of rehabilitation programs.

The relationship between external knee moments and muscle co-activation in subjects with medial knee osteoarthritis

PURPOSE External knee moments are reliable to measure knee load but it does not take into account muscle activity. Considering that muscle co-activation increases compressive forces at the knee joint, identifying relationships between muscle co-activations and knee joint load would complement the investigation of the knee loading in subjects with knee osteoarthritis. The purpose of this study was to identify relationships between muscle co-activation and external knee moments during walking in subjects with medial knee osteoarthritis. METHODS 19 controls (11 males, aged 56.6±5, and BMI 25.2±3.3) and 25 subjects with medial knee osteoarthritis (12 males, aged 57.3±5.3, and BMI 28.2±4) were included in this study. Knee adduction and flexion moments, and co-activation (ratios and sums of quadriceps, hamstring, and gastrocnemius) were assessed during walking and compared between groups. The relationship between knee moments and co-activation was investigated in both groups. FINDINGS Subjects with knee osteoarthritis presented a moderate and strong correlation between co-activation (ratios and sums) and knee moments. INTERPRETATION Muscle co-activation should be used to measure the contribution of quadriceps, hamstring, and gastrocnemius on knee loading. This information would cooperate to develop a more comprehensive approach of knee loading in this population.

Ankle strength impairments associated with knee osteoarthritis

Background Knee Osteoarthritis seems to negatively impact ankle biomechanics. However, the effect of knee osteoarthritis on ankle muscle strength has not been clearly established. This study aimed to evaluate the ankle strength of the plantar flexors and dorsiflexors of patients with knee osteoarthritis in different degrees of severity. Methods Thirty‐seven patients with knee osteoarthritis and 15 controls, subjected to clinical and radiographic analysis, were divided into three groups: control, mild, and moderate knee osteoarthritis. Participants answered a self‐reported questionnaire and accomplished a muscle torque assessment of the ankle using the Biodex dynamometer in isometric, concentric and eccentric modes. Findings The mild osteoarthritis group (peak torque = 26.85(SD 3.58)) was significantly weaker than the control (peak torque = 41.75(SD 4.42)) in concentric plantar flexion (P < 0.05). The control and mild osteoarthritis groups were not significantly different from the moderate osteoarthritis group (peak torque = 36.12(SD 4.61)) in concentric plantar flexion. There were no significant differences for dorsiflexion among the groups; however the control and moderate osteoarthritis groups presented large and medium standardized mean differences. The mild osteoarthritis group was significantly lower than the control and moderate osteoarthritis groups in the concentric plantar flexion by concentric dorsiflexion torque ratio. Interpretation Ankle function exhibited impairments in patients with knee osteoarthritis, especially in the plantar flexion torque, in which the mild osteoarthritis group was weaker than the control. Interestingly, patients with moderate knee osteoarthritis showed results similar to the control group in plantar flexion torque. The results raise the possibility of a compensatory mechanism of the plantar flexors developed by patients in more advanced degrees to balance other muscle failures. HighlightsKnee osteoarthritis subjects exhibit impairment in muscle strength of the ankle.Mild osteoarthritis subjects had lower plantar flexion torque than healthy subjects.Moderate osteoarthritis subjects had similar plantar flexion torque to healthy subjects.The results suggest a possible compensation mechanism carried out by the plantar flexors.

ECU convention 2017 research presentations

O-01 Care seeking patterns during one year after visiting a chiropractor Alice Kongsted, Lise Hestbaek Nordic Institute of Chiropractic and Clinical Biomechanics, University of Southern Denmark, 5230 Odense M, Denmark; Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, 5230 Odense M, Denmark Correspondence: Alice Kongsted (a.kongsted@nikkb.dk) Chiropractic & Manual Therapies 2017, 25(Suppl 1):O-01

FRI0580-HPR Correlation between Self-Reported Physical Function and Isokinetic Total Muscle Work in Early Degrees of Knee Osteoarthritis

Background Knee osteoarthritis (OA) is the most common chronic joint disease. Quadriceps is the muscle around the knee joint more affected by the disease, resulting in a reduction in functional muscle parameters. This may contribute to substantial functional deficits, however it is not clear if functional muscle parameters, like total muscle work, correlates to physical function in early degrees of knee osteoarthritis. Objectives The aim of this study was to evaluate the correlation between functional impairment and knee extensor total muscle work in men with Grades I or II knee OA. Methods Fourteen men with knee OA grade I or II (according to Kellgren & Lawrance criteria) participated in this study. The physical function section of the Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) questionnaire was applied before the isokinetic evaluation. The concentric and eccentric knee extensor total muscle work were assessed using Biodex System 3 Pro isokinetic dynamometer, at a speed of 90°/s. Spearmans correlation coefficient was used to detect the relationship between the dependent variables (WOMAC questionnaire physical function section score) and the independent variables (average total muscle work). For all the statistical tests, the significance level was p<0.05. Results The data analysis revealed a moderate and negative correlation between self-reported physical function and eccentric extensor total muscle work (r= -0.8, p=0,001). The self-reported physical function presented no correlation with concentric extensor total muscle work (r= -0.5, p=0,07).These results indicate that the higher the knee extensor eccentric total muscle work, the lower the level of functional impairment self-reported by these individuals. Conclusions Our results indicate that correlation between eccentric knee extensor total muscle work and self-reported physical function are already present in individual with early degrees of knee OA. These results also indicate the lower the total work, the greater the functional deficit.Thus, physical therapy programs are indicated for these patients to improve physical function, especially in functional activities involving eccentric contraction of the quadriceps. References American College of Rheumatology Subcommittee on Osteoarthritis Guidelines.Recommendations for the medical management of osteoarthritis of the hip and knee: 2000 update. Arthritis Rheum 2000; 43:1905-15. Brandt KD, Dieppe PA, Eric R. Etiopathogenesis of osteoarthritis.Med Clin N Am 2009; 93: 1-24. Kellgren, J H, Lawrence, J S. Radiological assessment of osteo-arthrosis. Ann Rheum Dis, 1957; 16: 494-502. Weber JC, Lamb DR. Statistics and Research in Physical Education. Saint Luis: C.V; Mosby Company; 1970. Acknowledgements The Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP), São Paulo, Brazil for financial support (#2007/07200-4; #2011/06619-7). Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.3807