Living with joint hypermobility syndrome: patient experiences of diagnosis, referral and self-care.

BACKGROUND: Musculoskeletal problems are common reasons for seeking primary health care. It has been suggested that many people with 'everyday' non-inflammatory musculoskeletal problems may have undiagnosed joint hypermobility syndrome (JHS), a complex multi-systemic condition. JHS is characterized by joint laxity, pain, fatigue and a wide range of other symptoms. Physiotherapy is usually the preferred treatment option for JHS, although diagnosis can be difficult. The lived experience of those with JHS requires investigation. OBJECTIVE: The aim of the study was to examine patients' lived experience of JHS, their views and experiences of JHS diagnosis and management. METHODS: Focus groups in four locations in the UK were convened, involving 25 participants with a prior diagnosis of JHS. The focus groups were audio recorded, fully transcribed and analysed using the constant comparative method to inductively derive a thematic account of the data. RESULTS: Pain, fatigue, proprioception difficulties and repeated cycles of injury were among the most challenging features of living with JHS. Participants perceived a lack of awareness of JHS from health professionals and more widely in society and described how diagnosis and access to appropriate health-care services was often slow and convoluted. Education for patients and health professionals was considered to be essential. CONCLUSIONS: Timely diagnosis, raising awareness and access to health professionals who understand JHS may be particularly instrumental in helping to ameliorate symptoms and help patients to self-manage their condition. Physiotherapists and other health professionals should receive training to provide biopsychosocial support for people with this condition.

The effect of stimulus number on the stability of responses for an extensive heat pain test.

BACKGROUND: The use of relatively lower stimulus presentation numbers in quantitative sensory testing may influence the computation accuracy of participants' discriminability. The minimum trial number for obtaining a stabilized participant discrimination ability was determined. MATERIALS AND METHODS: Twelve participants' ability to discriminate between noxious heat stimuli pairs (45°C/46°C, 46°C/47°C, and 47°C/48°C) was assessed using a six-category confidence rating scale. Heat stimuli were administered to the forearm. Two conditions with presentation numbers of 17 trials per stimulus (representing the median number of trials in previous studies) and 40 trials per stimulus (used in a previous study with a similar protocol) were used. RESULTS AND DISCUSSION: Participants' discriminability stabilized at approximately the 20th trial based on the lowest frequency of indeterminate and non-model conforming results under both conditions. A simple linear regression model showed a statistically significant positive relationship between discriminability for the two conditions (slope = 0.65, p < 0.001; constant = 0.33, p = 0.02; r(2 )= 0.51). As a rule of thumb, approximately 20 trials per stimulus intensity could be used to obtain a stabilized discriminability outcome.

Repeatability of joint proprioception and muscle torque assessment in healthy children and in children diagnosed with hypermobility syndrome.

BACKGROUND: Impairment of joint proprioception in patients with hypermobility syndrome (HMS) has been well documented. Both joint proprioception and muscle torque are commonly assessed in patients with musculoskeletal complaints. It is unknown, however, if these measures change significantly on repeated application in healthy children and in children with HMS. AIM: To investigate the between-days repeatability of joint proprioception and muscle torque in these groups. METHODS: Twenty children (10 healthy and 10 with HMS), aged eight to 15 years, were assessed on two separate occasions (one week apart) for joint kinaesthesia (JK), joint position sense (JPS), and the extensor and knee flexor muscle torque of the knee. JK was measured using threshold to detection of passive movement. JPS was measured using the absolute angular error (AAE; the absolute difference between the target and perceived angles). Knee extensor and flexor muscle torque was normalized to body weight. RESULTS: Intra-class correlation coefficients (ICC) for JK, extensor and flexor muscle torque were excellent in both groups (range 0.83 to 0.98). However, ICC values for JPS tests were poor to moderate in the two groups (range 0.18 to 0.56). 95% limits of agreement (LOA) were narrow in both cohorts for JK and muscle torque (indicating low systematic error) but wide for the JPS tests. 95% LOA also demonstrated that the measuring instruments used in this study had low between-days systematic error. CONCLUSIONS: Based on ICC and 95% LOA, the repeatability of JK and muscle torque measurements was excellent in both healthy children and those with HMS. The JPS test can only be assessed with poor to moderate repeatability. The use of the JPS test in these children should be undertaken with caution.

Detection theory analysis of scaling and discrimination tasks: responses to noxious thermal stimuli.

This study's main purpose was to examine the sensitivity estimates obtained from scaling and discrimination approaches for nociception assessment in healthy individuals. This investigation may inform future applications in diagnostic procedures for painful conditions. Models of psychophysical judgment based on those of Durlach and Braida (1969), Laming (1984), and Irwin and Whitehead (1991) were used as the common analytical framework. Noxious thermal contact stimuli were used. The results show that the scaling approach produced lower detection theory sensitivity estimates than did the discrimination approach. The additional judgment variance in scaling tasks could explain this lowered sensitivity. The relative judgmental variance value of 2.18 obtained in this study is lower than variance values found i n previous investigations. This discrepancy i s probably due to the relatively smaller stimulus range employed in this study. The authors propose that the theoretical framework used in this study may be used in future studies to investigate the different dimensions of pain perception.

Thermal perception thresholds recorded using method of limits change over brief time intervals.

Quantitative Sensory Testing (QST) of thermal perception thresholds assesses small afferent nerve function. QST has also been widely used to investigate the effects of interventions on the perception of activity within these nerve fibres, often over brief time periods. The natural variation in perception thresholds over brief time periods has not been determined, however, complicating accurate identification of induced changes. The present study therefore investigated changes in thermal perception threshold values within a 1-h period. Twenty-four healthy women volunteers aged 18-28 years (mean 20.6, SD 2.8) undertook cold sensation (CS), warm sensation (WS), cold pain (CP), and hot pain (HP) perception threshold measurements on the thenar eminence of the dominant hand during six 8-min experimental cycles. The order of stimulus presentation was randomized within pre-selected criteria. An adaptation temperature of 32 degrees C, a rate of temperature change of 0.5 degrees C/s, a 3 cm x 3 cm thermode, and a method of limits algorithm were used. Separate two-way ANOVAs with repeated measures showed statistically significant changes over time for WS, CS, and HP (p < 0.05), but not for CP (p = 0.232). The results indicate that WS, CS, and HP perception thresholds change significantly with repeated testing over a 1-h period. These results should be carefully considered when assessing the importance of observed changes in thermal perception thresholds. In research trials exclusion of a control group would be a fundamental flaw.

Effects of electric stimulation on C and A delta fiber-mediated thermal perception thresholds.

OBJECTIVE: To determine if interferential current (IFC) or transcutaneous electric nerve stimulation (TENS) alters C and A delta fiber-mediated thermal perception thresholds. DESIGN: Single-blind, randomized controlled trial. SETTING: Laboratory. PARTICIPANTS: One hundred forty healthy women volunteers (mean age +/- standard deviation, 20.6+/-2.7 y). INTERVENTIONS: Subjects were randomly and exclusively assigned to 1 of 7 groups (n=20 in each): 0, 5, and 100 Hz of IFC; 5 and 100 Hz of TENS; placebo and control stimulation. Stimulation was applied through 2 electrodes placed over the median nerve. Warm sensation, cold sensation, hot pain, and cold pain perception thresholds were measured from the thenar eminence by using a quantitative sensory testing device and a method of limits algorithm. MAIN OUTCOME MEASURES: Warm sensation, cold sensation, hot pain, and cold pain thresholds (degrees C) before, during, and after stimulation. RESULTS: There was a statistically significant effect of time for all 4 thermal perception thresholds (separate 2-way analyses of variance with repeated measures, all P<.001). There were no statistically significant differences between experimental groups, nor any interaction effects (all P>.05). CONCLUSIONS: Neither IFC nor TENS altered C and A delta fiber-mediated thermal perception thresholds. The results suggest that any analgesic mechanisms with these modalities are likely to be complex.