BackgroundIn adolescents with non-pathological and pathological joint hypermobility, gait deviations have been associated with pain and fatigue. It remains unclear what distinguishes the non-pathological form of joint hypermobility (JH) from pathological forms (i.e. hypermobile Ehlers-Danlos syndrome (hEDS) or hypermobility spectrum disorders (HSD). Our objective was to identify discriminative clinical characteristics and biomechanical gait features between adolescents with hEDS/HSD, JH, and healthy controls (HC).MethodsThirty-two adolescents were classified into three subgroups (hEDS/HSD=12, JH=5, HC=15). Clinical characteristics (e.g. pain intensity and surface, fatigue, functional disability) were inventoried.The gait pattern was assessed using a three-dimensional, eight-camera VICON MX1.3 motion capture system, operating at a sample rate of 100 Hz (VICON, Oxford, UK). Spatiotemporal parameters, joint angles (sagittal plane), joint work, joint impulse, ground reaction force and gait variability expressed as percentage using Principal Component Analysis (PCA) were assessed and analysed using multivariate analysis. Multivariate analysis data is expressed in mean differences(MD), standard error(SE) and P-values.ResultsThe hEDS/HSD-group had significantly higher fatigue score (+51.5 points, p = <0.001) and functional disability (+1.6, p < .001) than the HC-group. Pain intensity was significantly higher in the hEDS/HSD-group than the other subgroups (JH; +37 mm p = .004, HC; +38 mm, p = .001). The hEDS/HSD-group showed significantly more gait variability (JH; +7.2(2.0)% p = .003, HC; + 7.8(1.4)%, p = <0.001) and lower joint work (JH; −0.07(0.03)J/kg, p = .007, HC; − 0.06(0.03)J/kg, p = .013) than the other subgroups. The JH-group showed significantly increased ankle dorsiflexion during terminal stance (+5.0(1.5)degree, p = .001) compared to hEDS/HSD-group and knee flexion during loading response compared to HC-group (+5.7(1.8) degree, p = .011).SignificanceA distinctive difference in gait pattern between adolescents with non-pathological and pathological joint hypermobility is found in gait variability, rather than in the biomechanical features of gait. This suggests that a specific gait variability metric is more appropriate than biomechanical individual joint patterns for assessing gait in adolescents with hEDS/HSD.
PURPOSE: The patients diagnosed with Ehlers-Danlos Syndrome Hypermobility Type (EDS-HT) are characterized by pain, proprioceptive inacuity, muscle weakness, potentially leading to activity limitations. In EDS-HT, a direct relationship between muscle strength, proprioception and activity limitations has never been studied. The objective of the study was to establish the association between muscle strength and activity limitations and the impact of proprioception on this association in EDS-HT patients.METHODS: Twenty-four EDS-HT patients were compared with 24 controls. Activity limitations were quantified by Health Assessment Questionnaire (HAQ), Six-Minute Walk test (6MWT) and 30-s chair-rise test (30CRT). Muscle strength was quantified by handheld dynamometry. Proprioception was quantified by movement detection paradigm. In analyses, the association between muscle strength and activity limitations was controlled for proprioception and confounders.RESULTS: Muscle strength was associated with 30CRT (r = 0.67, p = <0.001), 6MWT (r = 0.58, p = <0.001) and HAQ (r = 0.63, p= <0.001). Proprioception was associated with 30CRT (r = 0.55, p < 0.001), 6MWT (r = 0.40, p = <0.05) and HAQ (r = 0.46, p < 0.05). Muscle strength was found to be associated with activity limitations, however, proprioceptive inacuity confounded this association.CONCLUSIONS: Muscle strength is associated with activity limitations in EDS-HT patients. Joint proprioception is of influence on this association and should be considered in the development of new treatment strategies for patients with EDS-HT. Implications for rehabilitation Reducing activity limitations by enhancing muscle strength is frequently applied in the treatment of EDS-HT patients. Although evidence regarding treatment efficacy is scarce, the current paper confirms the rationality that muscle strength is an important factor in the occurrence of activity limitations in EDS-HT patients. Although muscle strength is the most dominant factor that is associated with activity limitations, this association is confounded by proprioception. In contrast to common belief proprioception was not directly associated with activity limitations but confounded this association. Controlling muscle strength on the bases of proprioceptive input may be more important for reducing activity limitations than just enhancing sheer muscle strength.
Background: The modified painDETECT questionnaire (PDQ) is a self-reported questionnaire to discriminatebetween nociceptive and neuropathic-like pain in patients with knee/hip osteoarthritis (OA). This studyaims to assess the structural and construct validity of this questionnaire.Methods: Confirmatory factor analysis and hypothesis-testing was used. For 168 patients, predefinedhypotheses were formulated on the correlation between the modified painDETECT and several otherquestionnaires, and in a subsample of 46 with pain pressure thresholds (PPTs).Results: Two principal components were confirmed. The pain pattern item did not load on any component.Eighty per cent of the hypotheses on the correlation between modified PDQ and the questionnaireswere met, as were 50% concerning PPTs measurements.Conclusions: This study is the first to assess structural and construct validity of the modified PDQ knee/hip by using factor analysis and hypothesis-testing. This questionnaire seems to reflect neuropathic-like pain symptoms experienced by hip/knee OA-patients with adequate validity. The item on pain patternmight not reflect the construct. More than 75% of the predefined hypotheses regarding the modified PDQ and the other questionnaires were met. Only 50% of the hypotheses on PPTs measurements were met, probably due to heterogeneity and limited size of this subsample.
