(548) Trajectories of child pain and function in intensive interdisciplinary pediatric pain rehabilitation

Abstract

s The Journal of Pain S113 (548) Trajectories of child pain and function in intensive interdisciplinary pediatric pain rehabilitation C Hoffart, R Anderson, D Feltrop, M Wilson, B Dorton, A Chapman, and D Wallace; Children’s Mercy Hospital, Kansas City, MO Given the prevalence of pediatric chronic pain, degree of disability, and compromise in quality of life, there is a critical need to identify the natural history of pain anddisability. Few studies investigate the effect of interdisciplinary treatment on pain and functional trajectories in children with chronic musculoskeletal pain. We hypothesized function would improve prior to decrease in pain. 22 patients (18 female) aged 11-18 with chronic musculoskeletal pain completed the modified Bruce Treadmill Test, Functional Disability Inventory (FDI-patient), and reported pain using a 100mm Visual Analog Scale (VAS 0-100) at program start, the end of each week, and 19 completed one-month follow-up. One parent from each family completed FDI-parent, a measure of parent perception of pain-related functional limitations. Mean treatment program duration was 3.64 weeks (6 0.9). Patients’ pain worsens before it improves approximately halfway through the program. Pain increased from 61.7 at baseline to 72.1 and 67.5 at the end of weeks 1 (P=0.03) and 2 (P=0.22), respectively, with subsequent significant decrease in pain to 31.9 through post-treatment follow-up (P=0.001). Baseline patient and parent FDI scores correlated (27.6 and 25.5, respectively, r=.861; P< .0001) and demonstrated steady declines at week one and throughout treatment, indicating improved function prior to pain decrease. Patient FDI improved to 13.9 by program end (P<.0001) and continues to improve following treatment to 7.6 (P=.002). Bruce treadmill endurance increased steadily from baseline of 7.11 minutes with continued improvement through program end to 10.4 minutes (P<.0001). Concurrent trajectories of patient outcomes suggest that function improves before pain. Whereas pain gets worse during the first weeks of treatment, patient function increases within the first week. These trajectories may aid in determining the projected course for patients requiring intensive interdisciplinary pain rehabilitation. (549) Relationships among fear of pain and movement, strength test performance, and indicators of hypothalamic pituitary adrenal axis (HPA axis) activity E Dannecker and P Hinton; University of Missouri, Columbia, MO Two studies were located that tested associations between fear of pain and movement and performance during strength testing. They reported mixed results. In this study, we advance the literature by incorporating measures of Hypothalamic Pituitary Adrenal (HPA) axis activity – cortisol and blood pressure, whichwe collected directly before upper extremity strength tests. During a single session, healthy, upper-body untrained participants (N = 32, 46.9%women, 78% Caucasian, 24 yrs old (SD = 5.18)) completed measures of fear of pain and movement and pain catastrophizing before two consecutive strength tests using the non-dominant elbow flexors. Immediately before the strength tests, we collected blood pressure readings and saliva via an oral swab for cortisol. We also recorded perceived exertion, pain intensity, pain unpleasantness, and force output during the strength tests. Contrary to our hypotheses, we detected no significant associations among fear of pain and movement and cortisol, blood pressure, perceived effort, pain, or force output. However, systolic and diastolic blood pressure and perceived effort positively correlated with force output (r’s = .49 .61, p < .01; r’s = .57 .60, p < .01; r’s = .35 .42, p < .05). In addition, the total score of the Pain Catastrophizing Scale (PCS) and rumination subscale of the PCS inversely correlated with force output (r’s = -.37 -.40, p < .04; r’s = -.42 .46, p < .02). These results support that pain catastrophizing is more strongly related to force output than fear of pain and movement, but none of the psychological constructs were significantly associated with indicators of HPA axis activity. Future studies should test relationships among these variables in samples with clinical pain, conduct alternative types of strength and function tests, and administer otherHPAmeasures such as the corticotropin-releasing hormone challenge test. (550) Functional disability through initial and follow-up evaluations in a multidisciplinary pediatric headache clinic A Caruso, E Mahoney, L Lazdowsky, and A LeBel; Boston Children’s Hospital,