- Email: [email protected]
Effect of Forearm Warming Compared to Hand Warming for Cold Intolerance Following Upper Extremity Trauma
SCIENTIFIC ARTICLE
Effect of Forearm Warming Compared to Hand Warming for Cold Intolerance Following Upper Extremity Trauma Christine B. Novak, PhD,*† Yue Li, PhD,† Herbert P. von Schroeder, MD,* Dimitri J. Anastakis, MD,* Steven J. McCabe, MD* Purpose This study evaluated the effect of forearm or hand warming versus bare hand conditions to improve cold-induced symptoms and skin temperatures in hand trauma patients. Methods Adults with symptoms of cold intolerance at least 3 months following hand trauma and age-/sex-matched controls were included. Testing sessions (bare hand, hand warming, forearm warming) were completed in a climate laboratory with continuous temperature monitoring. Outcomes included physical findings (skin temperature) and self-report symptoms (thermal comfort, pain). Results Eighteen participants (9 hand trauma patients, 9 control subjects) underwent testing. More severe cold intolerance was associated with higher Disabilities of the Arm, Shoulder, and Hand scores. With bare hands, skin temperatures changed significantly from baseline to cold exposure and to rewarming. Hand trauma patients had the lowest skin temperatures with cold exposure in the injured digits (14.3 C 3.5 C) compared with the contralateral uninjured (16.9 C 4.1 C) digits. Compared with bare hands, wearing gloves significantly increased the minimum temperature during cold exposure and the maximum temperature after rewarming. Patients reported higher pain with cold exposure. All participants reported significantly more comfort with less coldness with forearm and hand warming. Conclusions There was cold response variability in hand trauma patients and control subjects. Hand trauma patients had greater changes in skin temperature during cold exposure that improved with glove warming. Continuous temperature monitoring identified subtle physiological changes associated with cold-induced pain and with warming interventions. (J Hand Surg Am. 2018;-(-):1.e1-e6. Copyright Ó 2018 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic III. Key words Cold intolerance, cold sensitivity, trauma, management.
From the *Toronto Western Hospital Hand Program, Department of Surgery; and the †Toronto Rehabilitation Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada. Received for publication November 9, 2017; accepted in revised form September 28, 2018. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Christine B. Novak, PhD, Toronto Western Hand Program, Department of Surgery, University of Toronto, 399 Bathurst St., 2EW-400, Toronto, Ontario, M5T 2S8 Canada; e-mail: [email protected]. 0363-5023/18/---0001$36.00/0 https://doi.org/10.1016/j.jhsa.2018.09.014
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an abnormal response of pain, numbness, stiffness, weakness, and/or color changes with exposure to cold temperatures. These cold-related symptoms may occur with hand trauma and may persist for many years.1e11 Although extreme cold temperatures can induce symptoms of cold intolerance, many patients report symptom exacerbation with even mild cold exposure.12 Some studies have examined the relationship between cold intolerance and patient factors, injury characteristics, and OLD INTOLERANCE IS DEFINED AS
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rewarming patterns and have produced varying results.2e4,6,9,13e16 Approaches to minimizing cold-induced symptoms have included protective strategies such as gloves and warm clothing to reduce cold temperature exposure.12 However, covering the hand can impede manual dexterity tasks. Torso warming has been used as a warming strategy in extreme cold environments.17,18 Studies in healthy individuals have shown the efficacy of torso warming compared with distal extremity warming with improvements in the physiological responses with extreme cold exposure.18 These results provide evidence regarding the vasodilatory benefits of central warming. Warming proximal to the hand may also produce vasodilatory effects and thus improve discomfort and skin temperatures associated with cold exposure. Fingerless gloves permit the digit pulps to be exposed, which may theoretically improve manual tasks but may also increase cold exposure to the most distal portion of the digit. Forearm warming may provide a nonobtrusive method of warming and allow the hands to be free to perform manual tasks with minimum obstruction. The main objective of this pilot study was to evaluate the effect of forearm warming versus hand warming and bare hand conditions to improve cold-induced pain and skin temperatures. We hypothesized that digit skin temperatures and self-reported symptoms would improve with forearm warming compared with hand warming and bare hand conditions.
Assessment Physical measures: Skin temperature was measured continuously throughout the testing period (baseline, cold exposure, recovery) using thermistor tips in direct contact with the skin at 8-second intervals with a data logger (Smartreader 8þ; ACR Systems, Markham, ON, Canada). The sites included the torso and 6 sites on the upper extremities bilaterally (extensor surface of the forearm, dorsum of the hand, and dorsum of the middle phalanx of the index, middle, ring, and little fingers). The physical assessments have been previously validated in a cold climate laboratory in a healthy elderly sample.19 Self-report questionnaires: Upper extremity disability and cold intolerance were assessed prior to climate laboratory testing. The Cold Intolerance Symptom Scale (CISS) was used to evaluate cold intolerance and to assess the overall level of symptoms and function with cold exposure.6,20 Each item score is summed to give a total score ranging from 0 to 100 with a higher score indicating a greater degree of cold intolerance; this scale has been shown to be valid and reliable.6,20,21 The Disabilities of the Arm, Shoulder, and Hand (DASH) was used to assess patient-reported upper extremity disability. A higher DASH score indicates a greater degree of disability.22e25 To assess the specific subjective responses with cold air exposure and warming interventions, pain and thermal comfort were evaluated at each testing session (baseline, cold exposure, and recovery). The McGill Pain Questionnaire short form (MPQ-SF) comprises pain descriptors, a pain intensity visual analog scale, and present pain intensity.26,27 Thermal comfort was assessed with the Thermal Sensation Scale (TSS) to indicate the self-reported comfort on a scale from very cold to very hot.
METHODS A repeated measures study design was used to evaluate the effect of forearm warming compared with hand warming and bare hand conditions on skin temperatures and self-report symptoms with cold exposure (Fig. 1). This study was approved by our institutional research ethics board.
Intervention Testing was performed in a simulated cold environment chamber and each participant wore a standard winter jacket (Ridge Point Clothing Co #16035, Toronto, ON, Canada). There were 3 testing sessions: forearm warming, hand warming, or bare hand conditions. To induce forearm warming, a batteryoperated warmer (Sunbeam Heat-to-Go Rechargeable Cordless Wrap, Brampton, ON, Canada) sleeve was placed on the affected forearm under the winter jacket. For hand warming, fingerless gloves (Auclair Ragg Wool Fingerless Gloves, Montreal, QC, Canada) were worn on both hands. Each session included 20 minutes baseline and recovery (22 C) and 20 minutes cold exposure (1 C) with continuous
Participants Following signed informed consent, adult patients who reported pain with cold exposure and were at least 3 months following hand trauma were included in this study. These hand trauma patients were sex(male vs female) and age- (within 2 years) matched to control participants. Control participants were recruited from our institution via employee communication. Exclusion criteria included a previous diagnosis of Raynaud phenomenon, peripheral vascular disease, carpal tunnel syndrome, peripheral neuropathy or upper motor neuron lesion, or inability to complete the questionnaires. J Hand Surg Am.
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FIGURE 1: Study protocol. In this study protocol, all participants received 3 testing sessions in standardized order (bare hand, fingerless glove, forearm warming) and testing was performed on different days.
skin temperature recording. Using previously validated methods in a cold climate laboratory in healthy elderly individuals, we tested the durations of cooling.19 Our results indicated that 20 minutes was sufficient to cool the extremities and not induce extreme discomfort. At the initial visit, participants completed the CISS, and DASH questionnaires. The MPQ-SF and TSS were completed at baseline, cold exposure, and recovery for each testing session.
differences in heating condition (forearm warming, hand warming, and bare hand) and test condition (baseline, cold exposure, and recovery). RESULTS The study included patients (n ¼ 9) with hand trauma (Table 1) and 9 age-/sex-matched control subjects. Compared with control subjects, hand trauma patients had significantly (P < .05) higher DASH and CISS scores (Table 2). Higher cold intolerance scores were correlated with higher DASH scores (r ¼ 0.8; P < .05). With cold exposure and bare hands, the overall mean skin temperature changed significantly (P < .05) from baseline (31.8 C 2.6 C), cold exposure (15.2 C 3.3 C), and rewarming (30.1 C 3.4 C). In hand trauma patients, the minimum cold temperature was lower in the injured digits (14.3 C 3.5 C) than in the contralateral hand uninjured digits (16.9 C 4.1 C). There was no correlation between CISS scores and minimum digit temperature. With
Statistical analysis Correlation coefficients were used to evaluate the relationships among the physical measures and cold intolerance, pain, and disability scores. In this preliminary study, a sample of 18 subjects provided adequate power to assess the correlational relationships between the physical performance and the patient-reported symptoms (a ¼ 0.05; b ¼ 0.20; r ¼ 0.6; 1-tail, n ¼ 16; 2-tail, n ¼ 19). A 2-way repeated measures analysis of variance was used to assess the J Hand Surg Am.
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TABLE 1. Patient
Patient Demographics Sex
Age (y)
Injury
Structures Involved
Surgery
1
Male
27
Fracture
Right index finger middle phalanx
No
2
Male
38
Laceration
Right middle finger replant
Yes
3
Female
32
Laceration
Bilateral repair flexor tendons, nerve and artery
Yes
4
Male
23
Laceration
Left index and middle finger repair flexor tendons and median nerve
Yes
5
Male
26
Fracture
Left ring and little finger middle phalanx
No
6
Female
59
Fracture
Left index finger distal phalanx
No
7
Male
26
Saw injury
Right index and middle finger repair flexor tendons and digital nerve
Yes
8
Male
30
Laceration
Right index and middle finger repair flexor tendon and digital nerve
Yes
9
Male
48
Laceration
Right ulnar nerve, artery, and tendon repair
Yes
TABLE 2.
Comparison of Questionnaire Scores
Hand Trauma Patients Mean Score SD
Control Subjects Mean Score SD
P Value Comparing Hand Trauma Patients and Control Subjects
DASH
21.0 14.7
2.5 2.7
< .01*
CISS
34.7 23.7
12.6 10.6
.03*
*Statistical significance at P < .05.
e1.65 1.20; glove e1.0 1.76; forearm, e0.90 1.29) versus noninjured digits (bare hand, e1.19 0.75; glove, 0.5 1.31; warmer, e0.81 0.65).
forearm warming, there was a negative correlation between CISS and thermal comfort scores (r ¼ e0.58; P < .05), indicating that those with more severe cold intolerance had less thermal comfort with this form of warming.
DISCUSSION Our study found variation in the responses to cold exposure in patients after hand trauma and in healthy control subjects. We found that wearing gloves and using forearm warmers improved patient-reported thermal comfort during cold exposure compared with bare hands. Wearing gloves also increased the minimal digital temperature during cold exposure. Hand trauma patients had a greater temperature drop from baseline to cold exposure, and the skin temperatures during cold exposure improved with glove warming. We found significant skin temperature differences with warming; using gloves significantly increased the lowest temperature during cold exposure and the maximum rewarming temperature; forearm warmers significantly increased the baseline temperatures. Hand trauma patients reported higher pain levels with cold exposure, and more severe cold intolerance was associated with greater disability.
Comparison of warming interventions and bare hand conditions The warming interventions had an overall significant effect (P < .05) on skin temperatures. The post hoc analyses showed that, compared with the bare hands, glove warming significantly (P < .05) increased the lowest temperature during cold exposure and the maximum rewarming temperature in hand trauma patients and control subjects (Fig. 2). The forearm warmers significantly (P < .05) increased the baseline temperatures in all subjects. Hand trauma patients reported higher pain levels with cold exposure. In hand trauma patients, we compared the thermal comfort between the injured digits in the affected hand and the uninjured digits in the contralateral hand. Thermal comfort was significantly better (P < .05) with forearm and glove warming than with bare hands: injured (bare hand, J Hand Surg Am.
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FIGURE 2: Comparison of warming interventions and bare hand conditions in patients with injured digits compared with control subjects. The mean skin temperatures comparing the patient with injured and control subject digits are presented for 3 conditions (bare hands, hand warming with fingerless gloves, and forearm warming). With hand and forearm warming, patients had slightly higher skin temperatures during cold exposure that was not significantly different. Because of the variability in baseline skin temperatures, the difference between baseline and lowest skin temperature with cold exposure was evaluated and the difference was significantly smaller (P < .05) in patients than in controls.
Patients with cold intolerance often use protective clothing such as wearing gloves to minimize cold exposure.12 In our study, wearing gloves did improve skin temperature with cold exposure. Other studies have investigated strategies to minimize the adverse responses with extreme cold conditions in healthy subjects using torso warming compared with hand and digit warming and found improved extremity temperatures and comfort with torso warming compared with hand warming.17,18,28 However, these studies were performed in young, healthy subjects under extreme cold conditions (temperature varied to e25 C) for prolonged durations. In our study, participants were exposed to 20 minutes of mild cold air exposure at the same time that electrically heated warmers were applied to the forearm of the affected hand. Although we were able to show elevated temperatures to the forearm throughout the testing periods and to the digits at baseline, the degree of warming was insufficient to increase distal digit skin temperatures with cold exposure. Immersion in cold water and cold air exposure are often used to induce responses to assess patients with J Hand Surg Am.
cold intolerance. Alterations in the method of inducing cold stress (air vs water) may affect the physiological and subjective responses.29,30 Many of the previous clinical studies assessing trauma-related cold intolerance have used cold water immersion and recorded temperatures after removal from the water.16,31,32 In our study, we utilized continuous temperature recordings and cold air exposure, which allowed for precise monitoring of the changes that occurred with cold exposure and rewarming. Previous studies using a different method of cold exposure (water immersion) and temperature monitoring after removal from the cold water may not be comparable with continuous temperature monitoring with cold air exposure. Our study provides preliminary data to illustrate the potential advantages of using cold air exposure with continuous skin temperature monitoring utilizing direct skin contact sensors. In this study, we were able to measure the lowest skin temperatures with cold air exposure and subsequent comparisons with self-reported pain and comfort. The strength of this study includes continuous skin temperature monitoring in a temperature-controlled r
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cold environment chamber and the comparison of a matched healthy cohort. We were able to show a significant increase in finger temperature with hand warming. With forearm warming, there was a significant increase in injured digit baseline temperatures but no significant difference with cold exposure. The limitation of this study includes a small sample of patients with various types of hand trauma and may be underpowered for the statistical subanalyses comparing group differences. Cold-induced pain and disability following hand trauma are complex constructs encompassing biomedical, physiological, and psychosocial factors. This study addressed an important clinical problem that directly affects hand trauma patients, and we found that glove warming was significantly better than forearm warming to improve skin temperatures with cold exposure.
12. Carlsson IK, Edberg AK, Wann-Hansson C. Hand-injured patients’ experiences of cold sensitivity and the consequences and adaptation for daily life: a qualitative study. J Hand Ther. 2010;23(1): 53e62. 13. Gustafsson M, Ahlström G. Problems experienced during the first year of an acute traumatic hand injury—a prospective study. J Clin Nurs. 2004;13(8):986e995. 14. Lied L, Lydersen S, Finsen V. Cold intolerance after flexor tendon injury. Disposing factors and long term prognosis. Scand J Surg. 2010;99(3):187e190. 15. Nijhuis TH, Smits ES, Jaquet JB, Van Oosterom FJ, Selles RW, Hovius SE. Prevalence and severity of cold intolerance in patients after hand fracture. J Hand Surg Eur Vol. 2010;35(4):306e311. 16. Smits ES, Nijhuis TH, Huygen FJ, Selles RW, Hovius SE, Niehof SP. Rewarming patterns in hand fracture patients with and without cold intolerance. J Hand Surg Am. 2011;36(4):670e676. 17. Brajkovic D, Ducharme MB, Frim J. Influence of localized auxiliary heating on hand comfort during cold exposure. J Appl Physiol (1985). 1998;85(6):2054e2065. 18. Brajkovic D, Ducharme MB. Finger dexterity, skin temperature, and blood flow during auxiliary heating in the cold. J Appl Physiol (1985). 2003;95(2):758e770. 19. Tajmir P, Grierson LE, Carnahan H. Interactions between cold ambient temperature and older age on haptic acuity and manual performance. Can J Aging. 2013;32(2):195e202. 20. Ruijs AC, Jaquet J-B, Daanen HA, Hovius SE. Cold intolerance of the hand measured by the CISS questionnaire in the normative study population. J Hand Surg Br. 2006;31(5):533e536. 21. Carlsson I, Cederlund R, Hoglund P, Lundborg G, Rosen B. Hand injuries and cold sensitivity: reliability and validity of cold sensitivity questionnaires. Disabil Rehabil. 2008;30(25):1920e1928. 22. Beaton DE, Katz JN, Fossel AH, Wright JG, Tarasuk V, Bombardier C. Measuring the whole or the parts? Validity, reliability, and responsiveness of the Disabilities of the Arm, Shoulder and Hand outcome measure in different regions of the upper extremity. J Hand Ther. 2001;14(2):128e146. 23. Gummesson C, Atroshi I, Ekdahl C. The disabilities of the arm, shoulder and hand (DASH) outcome questionnaire: longitudinal construct validity and measuring self-rated health change after surgery. BMC Musculoskel Disord. 2003;4:11. 24. Hudak PL, Amadio PC, Bombardier C. Development of an upper extremity outcome measure: the DASH (disabilities of the arm, shoulder and hand) [corrected]. The Upper Extremity Collaborative Group. Am J Ind Med. 1996;29(6):602e608. 25. SooHoo NF, McDonald AP, Seiler JG III, McGillivary GR. Evaluation of construct validity of the DASH questionnaire by correlation to the SF-36. J Hand Surg Am. 2008;27(3):537e541. 26. Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain. 1975;1(3):277e299. 27. Melzack R. The short-form McGill Pain Questionnaire. Pain. 1987;30(2):191e197. 28. Brajkovic D, Ducharme MB, Frim J. Relationship between body heat content and finger temperature during cold exposure. J Appl Physiol (1985). 2001;90(6):2445e2452. 29. Harada N. Cold-stress tests involving finger skin temperature measurement for evaluation of vascular disorders in hand-arm vibration syndrome: review of the literature. Int Arch Occup Environ Health. 2013;75(1e2):14e19. 30. Van der Struijs NR, Van Es EM, Raymann RJ, Daanen HA. Finger and toe temperatures on exposure to cold water and cold air. Aviat Space Environ Med. 2008;79(10):941e946. 31. Traynor R, MacDermid JC. Immersion in Cold-Water Evaluation (ICE) and self-reported cold intolerance are reliable but unrelated measures. Hand (N Y). 2008;3(3):212e219. 32. Smits ES, Selles RW, Huygen FJ, Duraku LS, Hovius SE, Walbeehm ET. Disordered conditioned pain modulation system in patients with posttraumatic cold intolerance. J Plast Reconstr Aesthetic Surg. 2014;67(1):68e73.
ACKNOWLEDGMENTS This study was supported by a research grant from the American Foundation for Surgery of the Hand. Presented at American Association for Hand Surgery Annual Meeting, Kona, Hawaii, January 12, 2017; Canadian Society for Hand Therapists Annual Meeting, Toronto, Ontario, May 6, 2016. REFERENCES 1. Campbell DA, Kay SP. What is cold intolerance? J Hand Surg Br. 1998;23(1):3e5. 2. Carlsson I, Rosen B, Dahlin LB. Self-reported cold sensitivity in normal subjects and in patients with traumatic hand injuries or handarm vibration syndrome. BMC Musculoskel Disord. 2010;11:89. 3. Collins ED, Novak CB, Mackinnon SE, Weisenborn SA. Long term follow-up of cold intolerance after nerve injury. J Hand Surg Am. 1996;21(6):1078e1085. 4. Craigen M, Kleinert JM, Crain GM, McCabe SJ. Patient and injury characteristics in the development of cold sensitivity of the hand: a prospective cohort study. J Hand Surg Am. 1999;24(1):8e15. 5. Graham B, Schofield M. Self-reported symptoms of cold intolerance in workers with injuries of the hand. Hand (N Y). 2008;3(3): 203e209. 6. Irwin MS, Gilbert SE, Terenghi G, Smith RW, Green CJ. Cold intolerance following peripheral nerve injury. Natural history and factors predicting severity of symptoms. J Hand Surg Br. 1997;22(3):308e316. 7. Nancarrow JD, Rai SA, Sterne GD, Thomas AK. The natural history of cold intolerance of the hand. Injury. 1996;27(9):607e611. 8. Povlsen B, Nylander G, Nylander E. Natural history of digital replantation: a 12-year prospective study. Microsurgery. 1995;16(3): 138e140. 9. Ruijs AC, Jaquet J-B, Van Riel WG, Daanen HA, Hovius SE. Cold intolerance following median and ulnar nerve injuries: prognosis and predictors. J Hand Surg Eur Vol. 2007;32(4):434e439. 10. Novak CB, McCabe SJ. Prevalence of cold sensitivity in patients with hand pathology. Hand (N Y). 2014;10(2):173e176. 11. Novak CB, Anastakis DJ, Beaton DE, Mackinnon SE, Katz J. Cold intolerance after brachial plexus nerve injury. Hand (N Y). 2012;7(1): 66e71.
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Effect of Forearm Warming Compared to Hand Warming for Cold Intolerance Following Upper Extremity Trauma Christine B. Novak, PhD,*† Yue Li, PhD,† Herbert P. von Schroeder, MD,* Dimitri J. Anastakis, MD,* Steven J. McCabe, MD* Purpose This study evaluated the effect of forearm or hand warming versus bare hand conditions to improve cold-induced symptoms and skin temperatures in hand trauma patients. Methods Adults with symptoms of cold intolerance at least 3 months following hand trauma and age-/sex-matched controls were included. Testing sessions (bare hand, hand warming, forearm warming) were completed in a climate laboratory with continuous temperature monitoring. Outcomes included physical findings (skin temperature) and self-report symptoms (thermal comfort, pain). Results Eighteen participants (9 hand trauma patients, 9 control subjects) underwent testing. More severe cold intolerance was associated with higher Disabilities of the Arm, Shoulder, and Hand scores. With bare hands, skin temperatures changed significantly from baseline to cold exposure and to rewarming. Hand trauma patients had the lowest skin temperatures with cold exposure in the injured digits (14.3 C 3.5 C) compared with the contralateral uninjured (16.9 C 4.1 C) digits. Compared with bare hands, wearing gloves significantly increased the minimum temperature during cold exposure and the maximum temperature after rewarming. Patients reported higher pain with cold exposure. All participants reported significantly more comfort with less coldness with forearm and hand warming. Conclusions There was cold response variability in hand trauma patients and control subjects. Hand trauma patients had greater changes in skin temperature during cold exposure that improved with glove warming. Continuous temperature monitoring identified subtle physiological changes associated with cold-induced pain and with warming interventions. (J Hand Surg Am. 2018;-(-):1.e1-e6. Copyright Ó 2018 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic III. Key words Cold intolerance, cold sensitivity, trauma, management.
From the *Toronto Western Hospital Hand Program, Department of Surgery; and the †Toronto Rehabilitation Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada. Received for publication November 9, 2017; accepted in revised form September 28, 2018. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Christine B. Novak, PhD, Toronto Western Hand Program, Department of Surgery, University of Toronto, 399 Bathurst St., 2EW-400, Toronto, Ontario, M5T 2S8 Canada; e-mail: [email protected]. 0363-5023/18/---0001$36.00/0 https://doi.org/10.1016/j.jhsa.2018.09.014
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an abnormal response of pain, numbness, stiffness, weakness, and/or color changes with exposure to cold temperatures. These cold-related symptoms may occur with hand trauma and may persist for many years.1e11 Although extreme cold temperatures can induce symptoms of cold intolerance, many patients report symptom exacerbation with even mild cold exposure.12 Some studies have examined the relationship between cold intolerance and patient factors, injury characteristics, and OLD INTOLERANCE IS DEFINED AS
Ó 2018 ASSH
r
Published by Elsevier, Inc. All rights reserved.
r
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rewarming patterns and have produced varying results.2e4,6,9,13e16 Approaches to minimizing cold-induced symptoms have included protective strategies such as gloves and warm clothing to reduce cold temperature exposure.12 However, covering the hand can impede manual dexterity tasks. Torso warming has been used as a warming strategy in extreme cold environments.17,18 Studies in healthy individuals have shown the efficacy of torso warming compared with distal extremity warming with improvements in the physiological responses with extreme cold exposure.18 These results provide evidence regarding the vasodilatory benefits of central warming. Warming proximal to the hand may also produce vasodilatory effects and thus improve discomfort and skin temperatures associated with cold exposure. Fingerless gloves permit the digit pulps to be exposed, which may theoretically improve manual tasks but may also increase cold exposure to the most distal portion of the digit. Forearm warming may provide a nonobtrusive method of warming and allow the hands to be free to perform manual tasks with minimum obstruction. The main objective of this pilot study was to evaluate the effect of forearm warming versus hand warming and bare hand conditions to improve cold-induced pain and skin temperatures. We hypothesized that digit skin temperatures and self-reported symptoms would improve with forearm warming compared with hand warming and bare hand conditions.
Assessment Physical measures: Skin temperature was measured continuously throughout the testing period (baseline, cold exposure, recovery) using thermistor tips in direct contact with the skin at 8-second intervals with a data logger (Smartreader 8þ; ACR Systems, Markham, ON, Canada). The sites included the torso and 6 sites on the upper extremities bilaterally (extensor surface of the forearm, dorsum of the hand, and dorsum of the middle phalanx of the index, middle, ring, and little fingers). The physical assessments have been previously validated in a cold climate laboratory in a healthy elderly sample.19 Self-report questionnaires: Upper extremity disability and cold intolerance were assessed prior to climate laboratory testing. The Cold Intolerance Symptom Scale (CISS) was used to evaluate cold intolerance and to assess the overall level of symptoms and function with cold exposure.6,20 Each item score is summed to give a total score ranging from 0 to 100 with a higher score indicating a greater degree of cold intolerance; this scale has been shown to be valid and reliable.6,20,21 The Disabilities of the Arm, Shoulder, and Hand (DASH) was used to assess patient-reported upper extremity disability. A higher DASH score indicates a greater degree of disability.22e25 To assess the specific subjective responses with cold air exposure and warming interventions, pain and thermal comfort were evaluated at each testing session (baseline, cold exposure, and recovery). The McGill Pain Questionnaire short form (MPQ-SF) comprises pain descriptors, a pain intensity visual analog scale, and present pain intensity.26,27 Thermal comfort was assessed with the Thermal Sensation Scale (TSS) to indicate the self-reported comfort on a scale from very cold to very hot.
METHODS A repeated measures study design was used to evaluate the effect of forearm warming compared with hand warming and bare hand conditions on skin temperatures and self-report symptoms with cold exposure (Fig. 1). This study was approved by our institutional research ethics board.
Intervention Testing was performed in a simulated cold environment chamber and each participant wore a standard winter jacket (Ridge Point Clothing Co #16035, Toronto, ON, Canada). There were 3 testing sessions: forearm warming, hand warming, or bare hand conditions. To induce forearm warming, a batteryoperated warmer (Sunbeam Heat-to-Go Rechargeable Cordless Wrap, Brampton, ON, Canada) sleeve was placed on the affected forearm under the winter jacket. For hand warming, fingerless gloves (Auclair Ragg Wool Fingerless Gloves, Montreal, QC, Canada) were worn on both hands. Each session included 20 minutes baseline and recovery (22 C) and 20 minutes cold exposure (1 C) with continuous
Participants Following signed informed consent, adult patients who reported pain with cold exposure and were at least 3 months following hand trauma were included in this study. These hand trauma patients were sex(male vs female) and age- (within 2 years) matched to control participants. Control participants were recruited from our institution via employee communication. Exclusion criteria included a previous diagnosis of Raynaud phenomenon, peripheral vascular disease, carpal tunnel syndrome, peripheral neuropathy or upper motor neuron lesion, or inability to complete the questionnaires. J Hand Surg Am.
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1.e3
FIGURE 1: Study protocol. In this study protocol, all participants received 3 testing sessions in standardized order (bare hand, fingerless glove, forearm warming) and testing was performed on different days.
skin temperature recording. Using previously validated methods in a cold climate laboratory in healthy elderly individuals, we tested the durations of cooling.19 Our results indicated that 20 minutes was sufficient to cool the extremities and not induce extreme discomfort. At the initial visit, participants completed the CISS, and DASH questionnaires. The MPQ-SF and TSS were completed at baseline, cold exposure, and recovery for each testing session.
differences in heating condition (forearm warming, hand warming, and bare hand) and test condition (baseline, cold exposure, and recovery). RESULTS The study included patients (n ¼ 9) with hand trauma (Table 1) and 9 age-/sex-matched control subjects. Compared with control subjects, hand trauma patients had significantly (P < .05) higher DASH and CISS scores (Table 2). Higher cold intolerance scores were correlated with higher DASH scores (r ¼ 0.8; P < .05). With cold exposure and bare hands, the overall mean skin temperature changed significantly (P < .05) from baseline (31.8 C 2.6 C), cold exposure (15.2 C 3.3 C), and rewarming (30.1 C 3.4 C). In hand trauma patients, the minimum cold temperature was lower in the injured digits (14.3 C 3.5 C) than in the contralateral hand uninjured digits (16.9 C 4.1 C). There was no correlation between CISS scores and minimum digit temperature. With
Statistical analysis Correlation coefficients were used to evaluate the relationships among the physical measures and cold intolerance, pain, and disability scores. In this preliminary study, a sample of 18 subjects provided adequate power to assess the correlational relationships between the physical performance and the patient-reported symptoms (a ¼ 0.05; b ¼ 0.20; r ¼ 0.6; 1-tail, n ¼ 16; 2-tail, n ¼ 19). A 2-way repeated measures analysis of variance was used to assess the J Hand Surg Am.
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TABLE 1. Patient
Patient Demographics Sex
Age (y)
Injury
Structures Involved
Surgery
1
Male
27
Fracture
Right index finger middle phalanx
No
2
Male
38
Laceration
Right middle finger replant
Yes
3
Female
32
Laceration
Bilateral repair flexor tendons, nerve and artery
Yes
4
Male
23
Laceration
Left index and middle finger repair flexor tendons and median nerve
Yes
5
Male
26
Fracture
Left ring and little finger middle phalanx
No
6
Female
59
Fracture
Left index finger distal phalanx
No
7
Male
26
Saw injury
Right index and middle finger repair flexor tendons and digital nerve
Yes
8
Male
30
Laceration
Right index and middle finger repair flexor tendon and digital nerve
Yes
9
Male
48
Laceration
Right ulnar nerve, artery, and tendon repair
Yes
TABLE 2.
Comparison of Questionnaire Scores
Hand Trauma Patients Mean Score SD
Control Subjects Mean Score SD
P Value Comparing Hand Trauma Patients and Control Subjects
DASH
21.0 14.7
2.5 2.7
< .01*
CISS
34.7 23.7
12.6 10.6
.03*
*Statistical significance at P < .05.
e1.65 1.20; glove e1.0 1.76; forearm, e0.90 1.29) versus noninjured digits (bare hand, e1.19 0.75; glove, 0.5 1.31; warmer, e0.81 0.65).
forearm warming, there was a negative correlation between CISS and thermal comfort scores (r ¼ e0.58; P < .05), indicating that those with more severe cold intolerance had less thermal comfort with this form of warming.
DISCUSSION Our study found variation in the responses to cold exposure in patients after hand trauma and in healthy control subjects. We found that wearing gloves and using forearm warmers improved patient-reported thermal comfort during cold exposure compared with bare hands. Wearing gloves also increased the minimal digital temperature during cold exposure. Hand trauma patients had a greater temperature drop from baseline to cold exposure, and the skin temperatures during cold exposure improved with glove warming. We found significant skin temperature differences with warming; using gloves significantly increased the lowest temperature during cold exposure and the maximum rewarming temperature; forearm warmers significantly increased the baseline temperatures. Hand trauma patients reported higher pain levels with cold exposure, and more severe cold intolerance was associated with greater disability.
Comparison of warming interventions and bare hand conditions The warming interventions had an overall significant effect (P < .05) on skin temperatures. The post hoc analyses showed that, compared with the bare hands, glove warming significantly (P < .05) increased the lowest temperature during cold exposure and the maximum rewarming temperature in hand trauma patients and control subjects (Fig. 2). The forearm warmers significantly (P < .05) increased the baseline temperatures in all subjects. Hand trauma patients reported higher pain levels with cold exposure. In hand trauma patients, we compared the thermal comfort between the injured digits in the affected hand and the uninjured digits in the contralateral hand. Thermal comfort was significantly better (P < .05) with forearm and glove warming than with bare hands: injured (bare hand, J Hand Surg Am.
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FIGURE 2: Comparison of warming interventions and bare hand conditions in patients with injured digits compared with control subjects. The mean skin temperatures comparing the patient with injured and control subject digits are presented for 3 conditions (bare hands, hand warming with fingerless gloves, and forearm warming). With hand and forearm warming, patients had slightly higher skin temperatures during cold exposure that was not significantly different. Because of the variability in baseline skin temperatures, the difference between baseline and lowest skin temperature with cold exposure was evaluated and the difference was significantly smaller (P < .05) in patients than in controls.
Patients with cold intolerance often use protective clothing such as wearing gloves to minimize cold exposure.12 In our study, wearing gloves did improve skin temperature with cold exposure. Other studies have investigated strategies to minimize the adverse responses with extreme cold conditions in healthy subjects using torso warming compared with hand and digit warming and found improved extremity temperatures and comfort with torso warming compared with hand warming.17,18,28 However, these studies were performed in young, healthy subjects under extreme cold conditions (temperature varied to e25 C) for prolonged durations. In our study, participants were exposed to 20 minutes of mild cold air exposure at the same time that electrically heated warmers were applied to the forearm of the affected hand. Although we were able to show elevated temperatures to the forearm throughout the testing periods and to the digits at baseline, the degree of warming was insufficient to increase distal digit skin temperatures with cold exposure. Immersion in cold water and cold air exposure are often used to induce responses to assess patients with J Hand Surg Am.
cold intolerance. Alterations in the method of inducing cold stress (air vs water) may affect the physiological and subjective responses.29,30 Many of the previous clinical studies assessing trauma-related cold intolerance have used cold water immersion and recorded temperatures after removal from the water.16,31,32 In our study, we utilized continuous temperature recordings and cold air exposure, which allowed for precise monitoring of the changes that occurred with cold exposure and rewarming. Previous studies using a different method of cold exposure (water immersion) and temperature monitoring after removal from the cold water may not be comparable with continuous temperature monitoring with cold air exposure. Our study provides preliminary data to illustrate the potential advantages of using cold air exposure with continuous skin temperature monitoring utilizing direct skin contact sensors. In this study, we were able to measure the lowest skin temperatures with cold air exposure and subsequent comparisons with self-reported pain and comfort. The strength of this study includes continuous skin temperature monitoring in a temperature-controlled r
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cold environment chamber and the comparison of a matched healthy cohort. We were able to show a significant increase in finger temperature with hand warming. With forearm warming, there was a significant increase in injured digit baseline temperatures but no significant difference with cold exposure. The limitation of this study includes a small sample of patients with various types of hand trauma and may be underpowered for the statistical subanalyses comparing group differences. Cold-induced pain and disability following hand trauma are complex constructs encompassing biomedical, physiological, and psychosocial factors. This study addressed an important clinical problem that directly affects hand trauma patients, and we found that glove warming was significantly better than forearm warming to improve skin temperatures with cold exposure.
12. Carlsson IK, Edberg AK, Wann-Hansson C. Hand-injured patients’ experiences of cold sensitivity and the consequences and adaptation for daily life: a qualitative study. J Hand Ther. 2010;23(1): 53e62. 13. Gustafsson M, Ahlström G. Problems experienced during the first year of an acute traumatic hand injury—a prospective study. J Clin Nurs. 2004;13(8):986e995. 14. Lied L, Lydersen S, Finsen V. Cold intolerance after flexor tendon injury. Disposing factors and long term prognosis. Scand J Surg. 2010;99(3):187e190. 15. Nijhuis TH, Smits ES, Jaquet JB, Van Oosterom FJ, Selles RW, Hovius SE. Prevalence and severity of cold intolerance in patients after hand fracture. J Hand Surg Eur Vol. 2010;35(4):306e311. 16. Smits ES, Nijhuis TH, Huygen FJ, Selles RW, Hovius SE, Niehof SP. Rewarming patterns in hand fracture patients with and without cold intolerance. J Hand Surg Am. 2011;36(4):670e676. 17. Brajkovic D, Ducharme MB, Frim J. Influence of localized auxiliary heating on hand comfort during cold exposure. J Appl Physiol (1985). 1998;85(6):2054e2065. 18. Brajkovic D, Ducharme MB. Finger dexterity, skin temperature, and blood flow during auxiliary heating in the cold. J Appl Physiol (1985). 2003;95(2):758e770. 19. Tajmir P, Grierson LE, Carnahan H. Interactions between cold ambient temperature and older age on haptic acuity and manual performance. Can J Aging. 2013;32(2):195e202. 20. Ruijs AC, Jaquet J-B, Daanen HA, Hovius SE. Cold intolerance of the hand measured by the CISS questionnaire in the normative study population. J Hand Surg Br. 2006;31(5):533e536. 21. Carlsson I, Cederlund R, Hoglund P, Lundborg G, Rosen B. Hand injuries and cold sensitivity: reliability and validity of cold sensitivity questionnaires. Disabil Rehabil. 2008;30(25):1920e1928. 22. Beaton DE, Katz JN, Fossel AH, Wright JG, Tarasuk V, Bombardier C. Measuring the whole or the parts? Validity, reliability, and responsiveness of the Disabilities of the Arm, Shoulder and Hand outcome measure in different regions of the upper extremity. J Hand Ther. 2001;14(2):128e146. 23. Gummesson C, Atroshi I, Ekdahl C. The disabilities of the arm, shoulder and hand (DASH) outcome questionnaire: longitudinal construct validity and measuring self-rated health change after surgery. BMC Musculoskel Disord. 2003;4:11. 24. Hudak PL, Amadio PC, Bombardier C. Development of an upper extremity outcome measure: the DASH (disabilities of the arm, shoulder and hand) [corrected]. The Upper Extremity Collaborative Group. Am J Ind Med. 1996;29(6):602e608. 25. SooHoo NF, McDonald AP, Seiler JG III, McGillivary GR. Evaluation of construct validity of the DASH questionnaire by correlation to the SF-36. J Hand Surg Am. 2008;27(3):537e541. 26. Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain. 1975;1(3):277e299. 27. Melzack R. The short-form McGill Pain Questionnaire. Pain. 1987;30(2):191e197. 28. Brajkovic D, Ducharme MB, Frim J. Relationship between body heat content and finger temperature during cold exposure. J Appl Physiol (1985). 2001;90(6):2445e2452. 29. Harada N. Cold-stress tests involving finger skin temperature measurement for evaluation of vascular disorders in hand-arm vibration syndrome: review of the literature. Int Arch Occup Environ Health. 2013;75(1e2):14e19. 30. Van der Struijs NR, Van Es EM, Raymann RJ, Daanen HA. Finger and toe temperatures on exposure to cold water and cold air. Aviat Space Environ Med. 2008;79(10):941e946. 31. Traynor R, MacDermid JC. Immersion in Cold-Water Evaluation (ICE) and self-reported cold intolerance are reliable but unrelated measures. Hand (N Y). 2008;3(3):212e219. 32. Smits ES, Selles RW, Huygen FJ, Duraku LS, Hovius SE, Walbeehm ET. Disordered conditioned pain modulation system in patients with posttraumatic cold intolerance. J Plast Reconstr Aesthetic Surg. 2014;67(1):68e73.
ACKNOWLEDGMENTS This study was supported by a research grant from the American Foundation for Surgery of the Hand. Presented at American Association for Hand Surgery Annual Meeting, Kona, Hawaii, January 12, 2017; Canadian Society for Hand Therapists Annual Meeting, Toronto, Ontario, May 6, 2016. REFERENCES 1. Campbell DA, Kay SP. What is cold intolerance? J Hand Surg Br. 1998;23(1):3e5. 2. Carlsson I, Rosen B, Dahlin LB. Self-reported cold sensitivity in normal subjects and in patients with traumatic hand injuries or handarm vibration syndrome. BMC Musculoskel Disord. 2010;11:89. 3. Collins ED, Novak CB, Mackinnon SE, Weisenborn SA. Long term follow-up of cold intolerance after nerve injury. J Hand Surg Am. 1996;21(6):1078e1085. 4. Craigen M, Kleinert JM, Crain GM, McCabe SJ. Patient and injury characteristics in the development of cold sensitivity of the hand: a prospective cohort study. J Hand Surg Am. 1999;24(1):8e15. 5. Graham B, Schofield M. Self-reported symptoms of cold intolerance in workers with injuries of the hand. Hand (N Y). 2008;3(3): 203e209. 6. Irwin MS, Gilbert SE, Terenghi G, Smith RW, Green CJ. Cold intolerance following peripheral nerve injury. Natural history and factors predicting severity of symptoms. J Hand Surg Br. 1997;22(3):308e316. 7. Nancarrow JD, Rai SA, Sterne GD, Thomas AK. The natural history of cold intolerance of the hand. Injury. 1996;27(9):607e611. 8. Povlsen B, Nylander G, Nylander E. Natural history of digital replantation: a 12-year prospective study. Microsurgery. 1995;16(3): 138e140. 9. Ruijs AC, Jaquet J-B, Van Riel WG, Daanen HA, Hovius SE. Cold intolerance following median and ulnar nerve injuries: prognosis and predictors. J Hand Surg Eur Vol. 2007;32(4):434e439. 10. Novak CB, McCabe SJ. Prevalence of cold sensitivity in patients with hand pathology. Hand (N Y). 2014;10(2):173e176. 11. Novak CB, Anastakis DJ, Beaton DE, Mackinnon SE, Katz J. Cold intolerance after brachial plexus nerve injury. Hand (N Y). 2012;7(1): 66e71.
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