Exploration of the Usual Care Pathway for Rotator Cuff Related Shoulder Pain in the Western Australian Workers' Compensation System.

PURPOSE: Investigate components of care for rotator cuff related shoulder pain in workers' compensation in relation to claim outcomes (claim duration, total medical spend, total claim cost, return to work outcome). METHODS: Engagement with (had care, time to care) four components of care (prescribed exercise, imaging, injections, surgery) were obtained from auditing 189 closed workers' compensation files. Associations were analysed between components of care and claim outcomes. RESULTS: 80% received prescribed exercise, 81% imaging, 42% injection and 35% surgery. Median time to imaging (11 days) was shorter than the prescribed exercise (27 days), with injection at 38 days and surgery 118.5 days. With univariable regression analysis higher age, the involvement of legal representation and the presence of rotator cuff pathology from diagnostic imaging (partial thickness tear or full thickness tear) were all associated with increased claim duration, total medical spend, total claim cost and less successful return to work outcomes. After adjusting for these three associations, having an injection or surgery were both positively associated with longer claim duration and greater medical spend, and surgery with greater total claim costs. In general, longer time to receiving components of care was associated with increased claim duration and reduced odds of returning to full duties at work. CONCLUSION: Early management was not consistent with clinical guidelines for managing workers' compensation rotator cuff related shoulder pain. This may negatively affect claims outcomes.

Endogenous Pain Modulation Induced by Extrinsic and Intrinsic Psychological Threat in Healthy Individuals.

Many factors interact to influence threat perception and the subsequent experience of pain. This study investigated the effect of observing pain (extrinsic threat) and intrinsic threat of pain to oneself on pressure pain threshold (PPT). Forty socially connected pairs of healthy volunteers were threat-primed and randomly allocated to experimental or control roles. An experimental pain modulation paradigm was applied, with non-nociceptive threat cues used as conditioning stimuli. In substudy 1, the extrinsic threat to the experimental participant was observation of the control partner in pain. The control participant underwent hand immersion in noxious and non-noxious water baths in randomized order. Change in the observing participant's PPT from baseline to mid- and postimmersion was calculated. A significant interaction was found for PPT between conditions and test time (F2,78 = 24.9, P < .005). PPT increased by 23.6% ± 19.3% between baseline and during hand immersion (F1,39 = 43.7, P < .005). Substudy 2 investigated threat of imminent pain to self. After a 15-minute break, the experimental participant's PPT was retested ("baseline 2"). Threat was primed by suggestion of whole arm immersion in an icier, larger water bath. PPT was tested immediately before anticipated arm immersion, after which the experiment ended. A significant increase in PPT between "baseline 2" and "pre-immersion" was seen (t = -7.6, P = .005), a pain modulatory effect of 25.8 ± 20.7%. Extrinsic and intrinsic threat of pain, in the absence of any afferent input therefore influences pain modulation. This may need to be considered in studies that use noxious afferent input with populations who show dysfunctional pain modulation. PERSPECTIVE: The effect on endogenous analgesia of observing another's pain and of threat of pain to oneself was investigated. Extrinsic as well as intrinsic threat cues, in the absence of any afferent input, increased pain thresholds, suggesting that mere threat of pain may initiate analgesic effects in traditional noxious experimental paradigms.