Prevention of Cold Injuries:

Patients who acquired an upper extremity nerve injury often complain about cold intolerance, reduced sensitivity and decreased task performance. This study tried to quantify these complaints and look in more detail at the thermal reaction to local cold exposure of the affected limb. We found that 36% of 107 subjects could be classified as cold intolerant. Eight of the cold intolerant subjects immersed their hands in 15°C water for 5 minutes after which infrared pictures of their affected hands were taken. The cold strain was acceptable for the patients. The damaged regions could easily be identified, most clearly 5 minutes after the hands were removed from the water. We conclude that the infrared temperature profile of the damaged hand after cold water immersion may be a helpful tool to assess the nerve damage. Similar tests exist for assessing the severity of non-freezing cold injuries (NFCI). We suggest that comparison of the results between NFCI and nerve injury patients may yield interesting information about the nervous involvement in NFCI. The method may also be valuable to identify subjects that have a higher risk for cold injuries. 1.0 INTRODUCTION Cold intolerance (= pain sensation in the hand on exposure to cold) is a frequent and invalidating finding both in nerve injury patients (Irwin et al., 1997; Lenoble et al., 1990) and in patients with non-freezing cold injuries (NFCI). The pathogenesis of cold intolerance is still essentially unclear. Cold intolerance is usually evaluated using the CISS (Cold Intolerance Severity Score) questionnaire in nerve injury patients (McCabe et al., 1991). In this study we aim to quantify the cold intolerance and sensitivity decrease in nerve injury patients and make a link to NFCI-patients. For NFCI-patients tests were developed to assess the cold injury severity (Francis and Oakley, 1996). We used a similar test for nerve injury patients to evaluate the outcome. 2.0 MATERIALS AND METHODS 2.1 Subjects A total of 107 upper extremity nerve injury patients participated in the study of which 88 patients performed the sensory recovery test. Eight subjects participated in a test using cold immersion of the hand. Jaquet, J.B.; Brandsma, M.; Daanen, H.A.M.; Hovius, S.E.R. (2005) Prevention of Cold Injuries: What can be Learned from Nerve Injury Patients? In Prevention of Cold Injuries (pp. 15-1 – 15-6). Meeting Proceedings RTO-MP-HFM-126, Paper 15. Neuilly-sur-Seine, France: RTO. Available from: http://www.rto.nato.int/abstracts.aps. Prevention of Cold Injuries: What can be Learned from Nerve Injury Patients? 15 2 RTO-MP-HFM-126 2.2 Measurements The patients completed the CISS (Cold Intolerance Symptom Severity) questionnaire at different time intervals. Sensory recovery was assessed by Semmes Weinstein monofilaments (North Coast Medical Inc, Morgan Hill, CA). The monofilaments (2.83, 3.61, 4.31, 4.56 and 6.10) were used according to the procedure described by Bell-Krotoski et al. (1995). Ten zones in the hand were tested, 6 in the area of the median nerve and 4 in the area of the ulnar nerve. The scores were interpreted as suggested by Imai et al. (1989). Based on the total score on the CISS questionnaire, eight patients were selected for investigation of thermoregulation in both hands (Posh et al., 2003). After 5 minutes immersion of both hands in a 15°C waterbath, infrared images were obtained at 0, 2, 5 and 10 minutes. Furthermore continuous temperature measurements during immersion and re-warming were performed. A FLIR ThermaCam SC2000 camera was used to measure the hands during rewarming. Figure 1: The subjects immersed both hands up to the styloids in a thermostat-controlled waterbath at 15°C for 5 minutes.