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Management of Adolescent Chronic Pelvic Pain from Endometriosis
J Pediatr Adolesc Gynecol (2003) 16:S17-S19
Management of Adolescent Chronic Pelvic Pain from Endometriosis: A Pain Center Perspective Christine D. Greco, MD Children’s Hospital and Harvard Medical School, Boston, Massachusetts
Abstract. Objectives: To review the options for the treatment of chronic pelvic pain in adolescents with endometriosis. Methods: Review of publications and description of author’s experience relating to adolescent endometriosis and pain treatment. Results: Pain treatment services offer a multidisciplinary approach for the treatment of chronic pelvic pain consisting of analgesic trials, cognitive-behavioral therapy, physical therapy, and complementary and alternative therapies. Patients are also evaluated for other conditions that might contribute to their chronic pain. Medication trials of antidepressants, anticonvulsants, tramadol, and nonsteroidal anti-inflammatory drugs are frequently used; however, there are limited data on efficacy. Biobehavioral techniques such as relaxation and biofeedback can help patients modify their experience of pain. Cognitive behavioral therapy can improve coping skills and promote improved functioning, particularly in patients who are debilitated from chronic pain. Transcutaneous electrical stimulation (TENS) and physical therapy approaches may be helpful in patients with musculoskeletal conditions that contribute to their pelvic pain. Complementary and alternative therapies are frequently used in the treatment of chronic pain; controlled trials are needed to assess efficacy. Conclusions: An individualized, multidisciplinary approach may be effective in improving overall outcome in patients with chronic pelvic pain in reducing pain and normalizing function.
Among adolescents seen at pediatric pain management clinics, pelvic pain is a common symptom and is frequently caused by endometriosis, affecting 45% to 70% of adolescents with chronic pelvic pain.1 One survey of 70,000 adolescents showed that almost 60% experienced dysmenorrhea and 50% of patients reported school absences because of severe pelvic pain.2 Many Address reprint requests to: Christine D. Greco, MD, Pain Treatment Service, Department of Anesthesia, 300 Longwood Ave., Boston, MA 02115; E-mail: [email protected] © 2003 North American Society for Pediatric and Adolescent Gynecology Published by Elsevier Science Inc.
adolescents with pelvic pain from endometriosis maintain normal activity, but those seen at pain clinics tend to represent a subgroup of patients who, despite aggressive medical and surgical therapy, continue to experience significant pain and disability. Patients typically have experienced moderate to severe pain for at least several months, have seen a variety of physicians, and usually have tried a number of analgesics. The Pain Treatment Service at Children’s Hospital, Boston uses a multidisciplinary treatment approach in the treatment of chronic pelvic pain consisting of selected medication trials, physical therapy, biobehavioral therapy, and complementary and alternative therapies. As with other chronic pain conditions, there is evidence to suggest that a multidisciplinary approach to the treatment of chronic pelvic pain is effective in improving patients’ response to therapy and in their overall outcome.3,4 Because pain associated with chronic pelvic pain may be multifactorial, patients are evaluated for other conditions in addition to endometriosis that might contribute to their chronic pain such as constipation, irritable bowel symptoms, lactose intolerance, myofascial pain, and psychosocial stressors. A biobehavioral approach is recommended, emphasizing the patient’s return to school, participation in social and family activities, and recognition of reinforcers of maladaptive behaviors. Because returning to school and participation in normal, age-appropriate activities is essential but often difficult for patients, a structured plan is often coordinated with the school and the psychologist. This is especially important for the adolescent who has been debilitated for a prolonged period of time and has subsequently developed signs of school avoidance. Antidepressants have neuromodulatory and analgesic properties and are frequently used in the treatment of a variety of chronic pain conditions.5–7 There is limited data, however, on the efficacy of tricyclic antidepressants (TCA) and serotonin reuptake inhibitors 1083-3188/03/$22.00 doi:10.1016/S1083-3188(03)00064-0
S18
Greco: Managing Chronic Pelvic Pain
(SSRI) for the treatment of chronic pelvic pain. Tricyclic antidepressants, such as nortriptyline and amitriptyline, may be helpful for patients with sleep disorders because of their sedative properties; however, higher doses may cause constipation and worsen pain in patients with existing constipation. Much lower doses of antidepressants are effective for pain relief than are required for the treatment of depression.8 A typical starting dose of nortriptyline or amitriptyline is 10 to 20 mg at bedtime. Because of rare cases of sudden death with the use of tricyclic antidepressants, a baseline ECG should be obtained to detect preexisting prolonged QTc or abnormal rhythm. Serotonin reuptake inhibitors have a wider safety margin than tricyclic antidepressants and may be useful for patients with chronic pain and depressed mood. Tramadol (Ultram®) is a centrally acting analgesic that is usually well tolerated by most patients. Although the exact mechanism of analgesia is not clearly understood, it is believed to involve weak binding of -receptors and inhibition of reuptake of norepinephrine and serotonin.9 Concomitant use of tramadol and TCA can potentially increase the risk of seizures. Chronic opioid use for the long-term management of nonmalignant chronic pelvic pain is controversial; however, in some cases opioids are used for short-term treatment of acute painful exacerbations in select patients. Cox-2 inhibitors, such as Celebrex® and Vioxx®, may be effective for patients who experience gastrointestinal distress with other nonsteroidal anti-inflammatory drugs (NSAIDs).10,11 There is little evidence for significant differences among NSAIDs in their analgesic effectiveness, particularly when comparisons are made with equipotent doses. There is some evidence to suggest that musculoskeletal conditions involving pelvic bones, muscles, ligaments, and joints may contribute to chronic pelvic pain and that physical therapy may provide pain relief in some patients.12,13 Further studies are needed to determine the efficacy of physical therapy approaches in the evaluation and treatment of pelvic pain. Transcutaneous electric nerve stimulation (TENS) is widely used as an adjuvant to chronic pain therapies, and many adolescents in our clinic with chronic pelvic pain have experienced pain relief with TENS.14 The pain-relieving effect of TENS is based on the Gate Control theory where stimulation of large unmyelinated A fibers by TENS inhibits the transmission of pain and other noxious stimuli through smaller unmyelinated C fibers to the dorsal horn. TENS is generally well tolerated by most patients and is associated with minimal risk. Controlled trials have given mixed results and suggest a considerable aspect of placebo effect in some settings. Additional randomized, clinical trials are needed to better define the efficacy of TENS.15 Cognitive and behavioral strategies, including guided
imagery, progressive muscle relaxation, biofeedback, and self-hypnosis, are integral components of a multidisciplinary approach to chronic pelvic pain management. Guided imagery is a form of relaxed, focused concentration that produces distraction from pain and is used as a coping mechanism.16 In progressive muscle relaxation, patients are taught to recognize and reduce muscle tension and anxiety associated with pain.17 Often, instructions are combined with suggestions of relaxing images. Through biofeedback, patients can modify the physical experience of pain through the use of specific instruments to detect and alter specific physiologic responses.18–20 Hypnosis is a technique of focused concentration used to achieve progressively deeper levels of relaxation and pain relief, and is used to achieve an altered state of consciousness.21–23 The use of self-hypnosis has been shown to improve pain and anxiety in adolescents undergoing pelvic examinations.24 Adolescents with chronic pain can experience associated depression, anxiety, and fear that may perpetuate and intensify their overall pain experience. In some cases, a patient’s emotional distress can interfere with biobehavioral treatment, physical therapy, and other pain management therapies. Many patients with chronic pelvic pain experience significant school absenteeism, social isolation, and altered family and peer interactions that can serve to reinforce chronic pain behaviors. In a survey of women with chronic pelvic pain, those with endometriosis reported the most health distress and interference of normal activities because of pain.25 Individual psychological consultation can help to identify and treat issues and can improve coping skills which can promote improved functioning with respect to chronic illness and pain. Patients and families are at times reluctant to consider psychological or psychiatric treatment for fear of attributing symptoms to a psychological origin. Education may be necessary to clarify that the effectiveness of psychological therapy does not imply a psychological origin to pain. There is an increasing trend in the United States towards the use of complementary and alternative medical therapies (CAM) to treat chronic pain conditions.26,27 Acupuncture is one of the most frequently used of CAM therapies.28,29 Of the 43 pediatric pain treatment services in North American children’s hospitals, 30% offer acupuncture services.30 Acupuncture is based on traditional Chinese medicine for pain relief, where energy (Chi) flows through the body along meridians connected by acupuncture points. A National Institutes of Health consensus conference concluded that acupuncture is effective in treating certain forms of pain, including dysmenorrhea.31 A retrospective study of pediatric patients at our pain treatment service showed that adolescents with endometriosis frequently used acupuncture and 70% of patients and 59% of parents felt that acupuncture helped their symptoms.28 Some individuals
Greco: Managing Chronic Pelvic Pain
may find relief from over-the-counter topical thermal or medicinal products. Controlled trials are needed to assess the efficacy of various CAM therapies for the management of chronic pain conditions. A multidisciplinary approach in treating chronic pelvic pain in adolescents combines medication trials, individualized cognitive and behavioral therapy, physical therapy, and CAM therapy. Treatment is directed at improving quality of life by reducing pain, disability, and maladaptive behaviors while improving patients’ function and ability to cope. Additional research is needed to understand visceral pain mechanisms and causes of persistence of pain. References 1. Laufer MR, Goitein L, Bush M, et al: Prevalence of endometriosis in adolescent girls with chronic pelvic pain not responding to conventional therapy. J Pediatr Adolesc Gynecol 1997;10: 199 2. Klein JR, Litt IF: Epidemiology of adolescent dysmenorrhea. Pedatrics 1981;68:661 3. Peters AA, van Dorst E, Jellis B, et al: A randomized clinical trial to compare two different approaches in women with chronic pelvic pain. Obstet Gynecol 1991;77:740 4. Kames LD, Rapkin AJ, Naliboff BD, et al: Effectiveness of an interdisciplinary pain management program for the treatment of chronic pelvic pain. 1990;41(1):41 5. Onghena P, Houdenhove BV: Antidepressant-induced analgesia in chronic nonmalignant pain: a meta-analysis of 39 placebo controlled studies. Pain 1992;49:205 6. Gram LF: Fluoxetine. N Engl J Med 1994;20:1354 7. Su X, Gebhart GF: Effects of tricyclic antidepressants on mechanosensitive pelvic nerve afferent fibers innervating the rat colon. Pain 1998;76:105 8. Reiter RC: Evidence-based management of chronic pelvic pain. Clin Obstet Gynecol 1998;41:422 9. Sindrup SH: Pharmacologic treatment of pain in polyneuropathy. Neurology 2000;55(7):915 10. Simon LS, Weaver AK, Graham DY, et al: Anti-inflammatory and upper gastrointestinal effects of celecoxib in rheumatoid arthritis: a randomized controlled trial [see comments]. JAMA 1999;282(20): 1921 11. Laine L, Harper S, Simon T, et al, Rofecoxib Osteoarthritis Endoscopy Study Group: A randomized trial comparing the effect of rofecoxib, a cyclooxygenase 2–specific inhibitor, with that of ibuprofen on the gastroduodenal mucosa of patients with osteoarthritis [see comments]. Gastroenterology 1999; 117(4):776 12. King PM, Myers CA, Ling FW: Musculoskeletal factors in chronic pelvic pain. J Psychosom Obstet Gynecol 1991; 12:87 13. Baker PK: Musculoskeletal origins of chronic pelvic pain. Diagnosis and treatment. Obstet Gynecol Clin North Am 1993;20(4):719
S19
14. Hamza MA: Effect of the frequency of transcutaneous electrical nerve stimulation on the postoperative opioid analgesic requirement and recovery profile. Anesthesiology 1999;91(5):1232 15. McQuay HJ, Moore RA, Eccleston C, et al: Systematic review of outpatient services for chronic pain control. Health Technol Assess 1997; 1(6):i,1 16. Eller LS: Guided imagery interventions for symptom management. Annu Rev Nurs Res 1999;17:57 17. Rusy LM: Complementary therapies for acute pediatric pain management. Pediatr Clin North Am 2000;47(3):589 18. Allen K, Shriver M: Enhanced performance feedback to strengthen biofeedback treatment outcome with childhood migraine. Headache 1997;37(3):169 19. Binder-Madleod S: Electromyographic biofeedback to improve voluntary motor control. In: Clinical Electrophysiology: Electrotherapy and Electrophysiologic Testing. Edited by AS-ML Robinson. Baltimore, Williams & Wilkins, 1995, pp 433–439 20. Marcus DA, Scharff L, Mercer S, et al: Nonpharmacological treatment for migraine: incremental utility of physical therapy with relaxation and thermal biofeedback. Cephalalgia 1998;18(5): 266,discussion 242 21. Dingas DF, Whitehouse WG, Orne EC, et al: Self-hypnosis training as an adjunctive treatment in the management of pain associated with sickle cell disease. Int J Clin Exp Hypn 1997;45(4):417 22. Rainville P, Carrier B, Hofbauer RK, et al: Dissociation of sensory and affective dimensions of pain using hypnotic modulation. Pain 1999; 82(2):159 23. Rainville P, Hofbauer RK, Paus T, et al: Cerebral mechanisms of hypnotic induction and suggestion. J Cogn Neurosci 1999;11(1):110 24. Kohen DP, Olness KN: The use of relaxation–mental imagery in the management of 505 pediatric behavioral encounters. Dev Behav Pediatr 1984;5:21 25. Mathias SO, Kupperman M, Lieberman RF, et al: Chronic pelvic pain: prevalence, health-related quality of life, and economic correlates. Obstet Gynecol 1996;87(3):321 26. Eisenberg DM, Davis RB, Ettner SL, et al: Trends in alternative medicine use in the United States, 1990–1997: results of a follow-up national survey [see comments]. JAMA 1998;280(18): 1569 27. Kemper KJ: Complementary and alternative medicine for children: does it work? Arch Dis Child 2001;84(1):6 28. Kemper KJ, Sarah R, Silver-Highfield E, et al: On pins and needles? Pediatric pain patients’ experience with acupuncture. Pediatrics 2000;105(4 Pt 2):941 29. Spigelblatt L, Laine-Ammara G, Pless IB, et al: The use of alternative medicine by children. Pediatrics 1994;94:811 30. Lin YC, Lee AC, Kemper KJ: Acupuncture services provided by pediatric pain treatment services in North America. 1999 31. Woollam CH, Jackson AO: Acupuncture in the management of chronic pain. Anaesthesia 1998;53:593
Management of Adolescent Chronic Pelvic Pain from Endometriosis: A Pain Center Perspective Christine D. Greco, MD Children’s Hospital and Harvard Medical School, Boston, Massachusetts
Abstract. Objectives: To review the options for the treatment of chronic pelvic pain in adolescents with endometriosis. Methods: Review of publications and description of author’s experience relating to adolescent endometriosis and pain treatment. Results: Pain treatment services offer a multidisciplinary approach for the treatment of chronic pelvic pain consisting of analgesic trials, cognitive-behavioral therapy, physical therapy, and complementary and alternative therapies. Patients are also evaluated for other conditions that might contribute to their chronic pain. Medication trials of antidepressants, anticonvulsants, tramadol, and nonsteroidal anti-inflammatory drugs are frequently used; however, there are limited data on efficacy. Biobehavioral techniques such as relaxation and biofeedback can help patients modify their experience of pain. Cognitive behavioral therapy can improve coping skills and promote improved functioning, particularly in patients who are debilitated from chronic pain. Transcutaneous electrical stimulation (TENS) and physical therapy approaches may be helpful in patients with musculoskeletal conditions that contribute to their pelvic pain. Complementary and alternative therapies are frequently used in the treatment of chronic pain; controlled trials are needed to assess efficacy. Conclusions: An individualized, multidisciplinary approach may be effective in improving overall outcome in patients with chronic pelvic pain in reducing pain and normalizing function.
Among adolescents seen at pediatric pain management clinics, pelvic pain is a common symptom and is frequently caused by endometriosis, affecting 45% to 70% of adolescents with chronic pelvic pain.1 One survey of 70,000 adolescents showed that almost 60% experienced dysmenorrhea and 50% of patients reported school absences because of severe pelvic pain.2 Many Address reprint requests to: Christine D. Greco, MD, Pain Treatment Service, Department of Anesthesia, 300 Longwood Ave., Boston, MA 02115; E-mail: [email protected] © 2003 North American Society for Pediatric and Adolescent Gynecology Published by Elsevier Science Inc.
adolescents with pelvic pain from endometriosis maintain normal activity, but those seen at pain clinics tend to represent a subgroup of patients who, despite aggressive medical and surgical therapy, continue to experience significant pain and disability. Patients typically have experienced moderate to severe pain for at least several months, have seen a variety of physicians, and usually have tried a number of analgesics. The Pain Treatment Service at Children’s Hospital, Boston uses a multidisciplinary treatment approach in the treatment of chronic pelvic pain consisting of selected medication trials, physical therapy, biobehavioral therapy, and complementary and alternative therapies. As with other chronic pain conditions, there is evidence to suggest that a multidisciplinary approach to the treatment of chronic pelvic pain is effective in improving patients’ response to therapy and in their overall outcome.3,4 Because pain associated with chronic pelvic pain may be multifactorial, patients are evaluated for other conditions in addition to endometriosis that might contribute to their chronic pain such as constipation, irritable bowel symptoms, lactose intolerance, myofascial pain, and psychosocial stressors. A biobehavioral approach is recommended, emphasizing the patient’s return to school, participation in social and family activities, and recognition of reinforcers of maladaptive behaviors. Because returning to school and participation in normal, age-appropriate activities is essential but often difficult for patients, a structured plan is often coordinated with the school and the psychologist. This is especially important for the adolescent who has been debilitated for a prolonged period of time and has subsequently developed signs of school avoidance. Antidepressants have neuromodulatory and analgesic properties and are frequently used in the treatment of a variety of chronic pain conditions.5–7 There is limited data, however, on the efficacy of tricyclic antidepressants (TCA) and serotonin reuptake inhibitors 1083-3188/03/$22.00 doi:10.1016/S1083-3188(03)00064-0
S18
Greco: Managing Chronic Pelvic Pain
(SSRI) for the treatment of chronic pelvic pain. Tricyclic antidepressants, such as nortriptyline and amitriptyline, may be helpful for patients with sleep disorders because of their sedative properties; however, higher doses may cause constipation and worsen pain in patients with existing constipation. Much lower doses of antidepressants are effective for pain relief than are required for the treatment of depression.8 A typical starting dose of nortriptyline or amitriptyline is 10 to 20 mg at bedtime. Because of rare cases of sudden death with the use of tricyclic antidepressants, a baseline ECG should be obtained to detect preexisting prolonged QTc or abnormal rhythm. Serotonin reuptake inhibitors have a wider safety margin than tricyclic antidepressants and may be useful for patients with chronic pain and depressed mood. Tramadol (Ultram®) is a centrally acting analgesic that is usually well tolerated by most patients. Although the exact mechanism of analgesia is not clearly understood, it is believed to involve weak binding of -receptors and inhibition of reuptake of norepinephrine and serotonin.9 Concomitant use of tramadol and TCA can potentially increase the risk of seizures. Chronic opioid use for the long-term management of nonmalignant chronic pelvic pain is controversial; however, in some cases opioids are used for short-term treatment of acute painful exacerbations in select patients. Cox-2 inhibitors, such as Celebrex® and Vioxx®, may be effective for patients who experience gastrointestinal distress with other nonsteroidal anti-inflammatory drugs (NSAIDs).10,11 There is little evidence for significant differences among NSAIDs in their analgesic effectiveness, particularly when comparisons are made with equipotent doses. There is some evidence to suggest that musculoskeletal conditions involving pelvic bones, muscles, ligaments, and joints may contribute to chronic pelvic pain and that physical therapy may provide pain relief in some patients.12,13 Further studies are needed to determine the efficacy of physical therapy approaches in the evaluation and treatment of pelvic pain. Transcutaneous electric nerve stimulation (TENS) is widely used as an adjuvant to chronic pain therapies, and many adolescents in our clinic with chronic pelvic pain have experienced pain relief with TENS.14 The pain-relieving effect of TENS is based on the Gate Control theory where stimulation of large unmyelinated A fibers by TENS inhibits the transmission of pain and other noxious stimuli through smaller unmyelinated C fibers to the dorsal horn. TENS is generally well tolerated by most patients and is associated with minimal risk. Controlled trials have given mixed results and suggest a considerable aspect of placebo effect in some settings. Additional randomized, clinical trials are needed to better define the efficacy of TENS.15 Cognitive and behavioral strategies, including guided
imagery, progressive muscle relaxation, biofeedback, and self-hypnosis, are integral components of a multidisciplinary approach to chronic pelvic pain management. Guided imagery is a form of relaxed, focused concentration that produces distraction from pain and is used as a coping mechanism.16 In progressive muscle relaxation, patients are taught to recognize and reduce muscle tension and anxiety associated with pain.17 Often, instructions are combined with suggestions of relaxing images. Through biofeedback, patients can modify the physical experience of pain through the use of specific instruments to detect and alter specific physiologic responses.18–20 Hypnosis is a technique of focused concentration used to achieve progressively deeper levels of relaxation and pain relief, and is used to achieve an altered state of consciousness.21–23 The use of self-hypnosis has been shown to improve pain and anxiety in adolescents undergoing pelvic examinations.24 Adolescents with chronic pain can experience associated depression, anxiety, and fear that may perpetuate and intensify their overall pain experience. In some cases, a patient’s emotional distress can interfere with biobehavioral treatment, physical therapy, and other pain management therapies. Many patients with chronic pelvic pain experience significant school absenteeism, social isolation, and altered family and peer interactions that can serve to reinforce chronic pain behaviors. In a survey of women with chronic pelvic pain, those with endometriosis reported the most health distress and interference of normal activities because of pain.25 Individual psychological consultation can help to identify and treat issues and can improve coping skills which can promote improved functioning with respect to chronic illness and pain. Patients and families are at times reluctant to consider psychological or psychiatric treatment for fear of attributing symptoms to a psychological origin. Education may be necessary to clarify that the effectiveness of psychological therapy does not imply a psychological origin to pain. There is an increasing trend in the United States towards the use of complementary and alternative medical therapies (CAM) to treat chronic pain conditions.26,27 Acupuncture is one of the most frequently used of CAM therapies.28,29 Of the 43 pediatric pain treatment services in North American children’s hospitals, 30% offer acupuncture services.30 Acupuncture is based on traditional Chinese medicine for pain relief, where energy (Chi) flows through the body along meridians connected by acupuncture points. A National Institutes of Health consensus conference concluded that acupuncture is effective in treating certain forms of pain, including dysmenorrhea.31 A retrospective study of pediatric patients at our pain treatment service showed that adolescents with endometriosis frequently used acupuncture and 70% of patients and 59% of parents felt that acupuncture helped their symptoms.28 Some individuals
Greco: Managing Chronic Pelvic Pain
may find relief from over-the-counter topical thermal or medicinal products. Controlled trials are needed to assess the efficacy of various CAM therapies for the management of chronic pain conditions. A multidisciplinary approach in treating chronic pelvic pain in adolescents combines medication trials, individualized cognitive and behavioral therapy, physical therapy, and CAM therapy. Treatment is directed at improving quality of life by reducing pain, disability, and maladaptive behaviors while improving patients’ function and ability to cope. Additional research is needed to understand visceral pain mechanisms and causes of persistence of pain. References 1. Laufer MR, Goitein L, Bush M, et al: Prevalence of endometriosis in adolescent girls with chronic pelvic pain not responding to conventional therapy. J Pediatr Adolesc Gynecol 1997;10: 199 2. Klein JR, Litt IF: Epidemiology of adolescent dysmenorrhea. Pedatrics 1981;68:661 3. Peters AA, van Dorst E, Jellis B, et al: A randomized clinical trial to compare two different approaches in women with chronic pelvic pain. Obstet Gynecol 1991;77:740 4. Kames LD, Rapkin AJ, Naliboff BD, et al: Effectiveness of an interdisciplinary pain management program for the treatment of chronic pelvic pain. 1990;41(1):41 5. Onghena P, Houdenhove BV: Antidepressant-induced analgesia in chronic nonmalignant pain: a meta-analysis of 39 placebo controlled studies. Pain 1992;49:205 6. Gram LF: Fluoxetine. N Engl J Med 1994;20:1354 7. Su X, Gebhart GF: Effects of tricyclic antidepressants on mechanosensitive pelvic nerve afferent fibers innervating the rat colon. Pain 1998;76:105 8. Reiter RC: Evidence-based management of chronic pelvic pain. Clin Obstet Gynecol 1998;41:422 9. Sindrup SH: Pharmacologic treatment of pain in polyneuropathy. Neurology 2000;55(7):915 10. Simon LS, Weaver AK, Graham DY, et al: Anti-inflammatory and upper gastrointestinal effects of celecoxib in rheumatoid arthritis: a randomized controlled trial [see comments]. JAMA 1999;282(20): 1921 11. Laine L, Harper S, Simon T, et al, Rofecoxib Osteoarthritis Endoscopy Study Group: A randomized trial comparing the effect of rofecoxib, a cyclooxygenase 2–specific inhibitor, with that of ibuprofen on the gastroduodenal mucosa of patients with osteoarthritis [see comments]. Gastroenterology 1999; 117(4):776 12. King PM, Myers CA, Ling FW: Musculoskeletal factors in chronic pelvic pain. J Psychosom Obstet Gynecol 1991; 12:87 13. Baker PK: Musculoskeletal origins of chronic pelvic pain. Diagnosis and treatment. Obstet Gynecol Clin North Am 1993;20(4):719
S19
14. Hamza MA: Effect of the frequency of transcutaneous electrical nerve stimulation on the postoperative opioid analgesic requirement and recovery profile. Anesthesiology 1999;91(5):1232 15. McQuay HJ, Moore RA, Eccleston C, et al: Systematic review of outpatient services for chronic pain control. Health Technol Assess 1997; 1(6):i,1 16. Eller LS: Guided imagery interventions for symptom management. Annu Rev Nurs Res 1999;17:57 17. Rusy LM: Complementary therapies for acute pediatric pain management. Pediatr Clin North Am 2000;47(3):589 18. Allen K, Shriver M: Enhanced performance feedback to strengthen biofeedback treatment outcome with childhood migraine. Headache 1997;37(3):169 19. Binder-Madleod S: Electromyographic biofeedback to improve voluntary motor control. In: Clinical Electrophysiology: Electrotherapy and Electrophysiologic Testing. Edited by AS-ML Robinson. Baltimore, Williams & Wilkins, 1995, pp 433–439 20. Marcus DA, Scharff L, Mercer S, et al: Nonpharmacological treatment for migraine: incremental utility of physical therapy with relaxation and thermal biofeedback. Cephalalgia 1998;18(5): 266,discussion 242 21. Dingas DF, Whitehouse WG, Orne EC, et al: Self-hypnosis training as an adjunctive treatment in the management of pain associated with sickle cell disease. Int J Clin Exp Hypn 1997;45(4):417 22. Rainville P, Carrier B, Hofbauer RK, et al: Dissociation of sensory and affective dimensions of pain using hypnotic modulation. Pain 1999; 82(2):159 23. Rainville P, Hofbauer RK, Paus T, et al: Cerebral mechanisms of hypnotic induction and suggestion. J Cogn Neurosci 1999;11(1):110 24. Kohen DP, Olness KN: The use of relaxation–mental imagery in the management of 505 pediatric behavioral encounters. Dev Behav Pediatr 1984;5:21 25. Mathias SO, Kupperman M, Lieberman RF, et al: Chronic pelvic pain: prevalence, health-related quality of life, and economic correlates. Obstet Gynecol 1996;87(3):321 26. Eisenberg DM, Davis RB, Ettner SL, et al: Trends in alternative medicine use in the United States, 1990–1997: results of a follow-up national survey [see comments]. JAMA 1998;280(18): 1569 27. Kemper KJ: Complementary and alternative medicine for children: does it work? Arch Dis Child 2001;84(1):6 28. Kemper KJ, Sarah R, Silver-Highfield E, et al: On pins and needles? Pediatric pain patients’ experience with acupuncture. Pediatrics 2000;105(4 Pt 2):941 29. Spigelblatt L, Laine-Ammara G, Pless IB, et al: The use of alternative medicine by children. Pediatrics 1994;94:811 30. Lin YC, Lee AC, Kemper KJ: Acupuncture services provided by pediatric pain treatment services in North America. 1999 31. Woollam CH, Jackson AO: Acupuncture in the management of chronic pain. Anaesthesia 1998;53:593