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Comparing the effectiveness of endoscopic carpal tunnel release between idiopathic and long-term hemodialysis patients
Formosan Journal of Surgery (2014) 47, 11e17
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ORIGINAL ARTICLE
Comparing the effectiveness of endoscopic carpal tunnel release between idiopathic and long-term hemodialysis patients Susan Yu-Chen Ho, Yu-Te Lin* Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Linkou, Taiwan Received 20 February 2013; received in revised form 7 March 2013; accepted 27 May 2013 Available online 30 December 2013
KEYWORDS Boston carpal tunnel questionnaire; carpal tunnel syndrome; endoscopic carpal tunnel release; hemodialysis; historical-objective scale; quickDASH questionnaire
Summary Background: Carpal tunnel syndrome (CTS) is recognized as an increasing morbidity in long-term hemodialysis patients. In general, the open method is the preferred technique of carpal tunnel release for most of the surgeons. Endoscopic carpal tunnel release (ECTR) is an alternative approach for idiopathic CTS, but its effectiveness for hemodialysisrelated patients is still under dispute. Objectives: The purpose of current study was to compare the effectiveness of ECTR in treating CTS between long-term hemodialysis patients and idiopathic patients. Methods: From November 2008 to March 2011, we consecutively collected 26 patients with idiopathic CTS and 22 long-term hemodialysis patients with CTS by a single surgeon. All patients received ECTR for decompression of the median nerve. The effectiveness between the two groups of patients was analyzed by clinical observation, historical-objective scale, two kinds of self-administered questionnaires (QuickDASH and Boston carpal tunnel questionnaires), and objectively by electrophysiological evaluation preoperatively and 3 months postoperatively. Results: With regard to the historical-objective scale, the hemodialysis group had significantly more severe grades than the idiopathic group in preoperative and postoperative evaluations. Both groups showed significant improvement after the ECTR. According to the selfadministered questionnaire results, there was no significant difference of the effectiveness of ECTR between the groups. Hemodialysis-related CTS was found to have more advanced
Conflicts of interest: The authors declare no conflicts of interest. * Corresponding author. Division of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, 5, Fu-Hsin Street, Kweishan, Taoyuan, Taiwan. E-mail address: [email protected] (Y.-T. Lin). 1682-606X/$ - see front matter Copyright ª 2013, Taiwan Surgical Association. Published by Elsevier Taiwan LLC. All rights reserved. http://dx.doi.org/10.1016/j.fjs.2013.05.007
12
S. Yu-Chen Ho, Y.-T. Lin electrophysiologic findings, and no significant improvement of electrophysiologic grading can be recognized in this group of patients. Conclusion: ECTR was effective in both groups of patients, but the severity of their preoperative status, especially with advanced involvement, may compromise the objective results. Although the results from the self-administered questionnaires and the electrophysiological findings were inconsistent in these hemodialysis-related patients, it is possible to have satisfactory results in symptoms and questionnaires but with the less satisfactory electrophysiological outcome. Copyright ª 2013, Taiwan Surgical Association. Published by Elsevier Taiwan LLC. All rights reserved.
1. Introduction
2. Materials and methods
Carpal tunnel syndrome (CTS) is the most common compression neuropathy of the upper extremity, and it accounts for 90% of all entrapment neuropathies.1,2 The typical symptoms of CTS include paresthesia, tingling sensation and/or pain on the palmar surface of the radial digits, and even motor weakness and signs of thenar muscle atrophy in an advanced disease.1e3 From a recent review by the Bureau of Health Promotion Department of Health, Taiwan, R.O.C., the incidence and prevalence of hemodialysis patients increased annually in Taiwan.4 Chronic renal failure has been recognized as one of the risk factors of CTS, and the risk increases annually in terms of duration of hemodialysis. Pathogenesis of the amyloid fibrils in the carpal tunnel was documented in 1986.5 Investigations found that one-third of chronic hemodialysis patients suffered CTS after <4 years of dialysis, a percentage that increased remarkably after 5 years, and reached nearly 100% after 20 years.6e8 In general, most surgeons prefer an open carpal tunnel release (OCTR) for long-term hemodialysis patients. The disease complexity and its progressive process were the major concerns by the surgeons when choosing the surgical technique.1e3,9,10 Nonetheless, OCTR may induce several morbidities, such as postoperative edema, bleeding, hypertrophic scar formation, infections, nerve injuries, and subsequently causes long periods of restriction of postoperative daily activities.9e11 The first endoscopic carpal tunnel release (ECTR) was described by Okutsu et al in 1989,12 and endoscopic decompression has been applied to idiopathic or any other secondary carpal tunnel syndrome ever since as a main competitor of the traditional OCTR procedure. Studies comparing OCTR and ECTR have generally concluded that, with its advantages of reduced scar pain, preservation of grip and pinch strength, and early return to work, ECTR is the beneficial application for CTS patients.12e15 The effectiveness of both procedures in idiopathic CTS patients appears to be equivalent and thus the ECTR has become a popular alternative carpal tunnel release method.16,17 However, there are not many reports discussing the efficacy of ECTR in terms of treating CTS patients with long-term hemodialysis. The purpose of the current study was to compare the effectiveness of ECTR in treating CTS between long-term hemodialysis patients and idiopathic patients.
The study was approved by the Institutional Review Board of Chang Gung Memorial Hospital, Taoyuan, Taiwan. From November 2008 to March 2011, we consecutively collected 26 patients with idiopathic CTS and 22 long-term hemodialysis patients with CTS by a single surgeon (Y.-T.L.).
2.1. Inclusion and exclusion criteria We excluded patients with risk factors of diabetes mellitus, rheumatoid arthritis, gout, and hypothyroidism. Patients with a past history of hand and wrist trauma were also excluded. Most of the patients were referred by neurologists. The diagnosis of CTS was mainly established by the typical signs and symptoms. Electrophysiology study was arranged for every patient pre- and postoperatively.
2.2. Surgical indications The surgical indications are based on the patient’s occupation, severity of clinical symptoms, advanced disease by nerve conduction tests, electrodiagnostic evidence of axon degeneration of the abductor pollicis brevis muscle, or a combination of these elements.
2.3. Operative procedures We used the CTS Relief Kit (ConMed Linvatec Biomaterials, Largo, FL, USA) and a 2.7-mm video assisted 0 endoscope for single portal ECTR (Menon’s technique).18 All surgeries were performed on an outpatient basis. The patient was placed in a supine position with the upper limb abducted on a hand table. Local anesthesia with 1% lidocaine was used to infiltrate the operative field. When there was an arterovenous fistula on the distal forearm and a rubber tourniquet could not be applied, diluted epinephrine (1:100,000) was added into the narcotics. For idiopathic patients, a rubber tourniquet was applied before incision. A 1-cm incision was made around the distal forearm crease ulnarly to the palmaris longus tendon. The incision was deepened to the antebrachial fascia. A small window was opened on the fascia. A freer was used to sound the carpal tunnel. Dilators of 5.5 mm and 7 mm were used to enlarge the carpal tunnel. A grooved cannula was then introduced
ECTR in idiopathic and hemodialysis CTS patients into the tunnel, and the transverse carpal ligament (TCL) could be observed through the endoscope. The TCL was transected by the endoscopic scalpel from proximal to distal. Complete division of the TCL was confirmed by observing fat dropping into the cannula at the proximal tunnel and observation of overlying muscle fibers at the middle and distal tunnel. Then the incision wound was closed. The average operation time was <15 minutes.
2.4. Postoperative care After the surgery, the patients were followed-up on the 2nd postoperative day, and after 1 month, 3 months, and 6 months. Dressings were changed on the 2nd day, and rehabilitation programs including massage and active range of motion were initiated at the same time. Offload of the hand for the 1st month was informed to the patient, and motorcycle riding was prohibited during this period.
2.5. Subjective and objective measurements The effectiveness between the two groups of patients was analyzed by clinical observation, historical-objective scale (HOS),19,20 two kinds of self-administered questionnaires [Boston carpal tunnel (BQ)21 and a short version of the disability of arm, shoulder, and hand questionnaire (QuickDASH)22] and objectively by electrophysiological evaluation preoperatively and 3 months postoperatively.
2.6. HOS Clinical assessment of the severity of CTS was made by using a 5-point clinical HOS. This scale includes any kind of paresthesia (night or day), objective sensory deficit, force of thumb abduction, and status of thenar muscles. A higher grade represents a greater severity of CTS.
13 median nerve and ulnar nerve. The amplitudes of sensory action potentials and compound muscle action potentials (CMAPs) were also measured. We then collected the DSL data and divided it into four grades according to the electrodiagnostic grade by Hankins et al.23 (Grade I, DSL: 3.7e4.19 ms, Grade II, DSL: 4.2e4.9 ms, Grade III, DSL: 5.0e7.0 ms, Grade IV, DSL: >7.0 ms.). For better confirmation, we also collected SCV and CMAP data and divided these into four grades according to the Tokyo electrodiagnostic grading of Iida et al24 (normal data: SCV 45 m/ s, CMAP 6 mV; mild: SCV < 45 m/s, CMAP 6 mV; moderate: SCV < 45 m/s, CMAP < 6 mV; severe: no sensory response).
2.10. Study protocol All the measurements were arranged at three time points as illustrated in Fig. 1. At the preoperative clinic, 3 months and 6 months after the operation, we evaluated the patients with two aspects: (1) subjectively, the clinical symptoms/signs, and complications and more specifically we graded it with HOS; and (2) objectively, we collected the preoperative and postoperative patient-oriented questionnaires (BQ and QuickDASH) and electrophysiologic studies.
2.11. Statistical analysis We used SPSS version 17 (SPSS Inc., Chicago, IL, USA) and nonparametric tests were employed for a limited case number. Wilcoxon signed rank test was used to compare HOS, electrophysiological grading (two grading systems), and questionnaire scores prior to and after the operation in each group. The ManneWhitney U test was applied to evaluate the differences of scores between the two groups at preoperative and postoperative time points. A pvalue < 0.05 was considered statistically significant.
2.7. BQ
3. Results For subjective evaluation of the severity of symptoms, the BQ (the validated Chinese version) was answered by patients. The questionnaire is divided into two parts: symptoms (11 items) and functional status (8 items). A higher score indicated a more severe impairment.
2.8. QuickDASH From the original DASH, a shorter version, the 11-item QuickDASH, was developed. Each item has five response options and, from the item scores, scale scores are calculated, ranging from 0 (no disability) to 100 (most severe disability). The validated Chinese version of QuickDASH was answered by patients.
2.9. Electrophysiologic study Neurophysiologic examination was performed by neurologists in our institute, which included a complete sensory conduction velocity (SCV) and motor conduction velocity, distal motor latency, and distal sensory latency (DSL) of the
The baseline conditions of the two patient groups are compared in Table 1. Basically, two comparable patient groups existed, except for the greater age of the hemodialysis group. No surgical complications, including nerve damage, hematoma, and wound infection, were noted in both groups. Symptoms of two patients in the hemodialysis group failed to respond to ECTR during the follow-up examinations. Extensive OCTR and neurolysis of the median nerve from the distal forearm to the palm was performed. Both patients reported partial relief of their symptoms thereafter.
3.1. HOS More than 90% of patients were noted with significant relief of pain and paresthesia on the 2nd day after the operation. In more than 95% of patients, the symptoms improved with time during the follow-ups. With regard to the HOS, the hemodialysis group had significantly more severe grades than the idiopathic group in preoperative and postoperative
14
S. Yu-Chen Ho, Y.-T. Lin
Figure 1
The study protocol.
evaluations. Both groups showed significant improvement after the ECTR (Table 2).
3.2. BQ and QuickDASH
showed less satisfactory results of hemodialysis patients after ECTR, which was statistically significant (Table 6).
4. Discussion
With regard to the evaluations by both questionnaires, neither the idiopathic group nor the hemodialysis group revealed significant improvement after ECTR (Table 3). Furthermore, when we compared the preoperative and postoperative conditions of the two groups (Table 4), the QuickDASH displayed the more advanced preoperative status of the hemodialysis group (p Z 0.015). While comparing the postoperative results of the QuickDASH, no significant difference was found between the two groups (p Z 0.811). By contrast, the BQ exhibited no difference in the disease status of the two groups preoperatively. Both groups of patients revealed similar improvement after ECTR by BQ, in both symptoms and functional status. Therefore, according to the self-administered questionnaire results, there was no significant difference in the effectiveness of ECTR between the groups.
3.3. Electrophysiological study Two grading systems were employed to measure the electrophysiological results. The Hankins grading system23 based on DSL data showed a significant improvement of the idiopathic patients after ECTR (p < 0.001), while there were limited changes in electrophysiological data of the hemodialysis patients postoperatively (Table 5). The Tokyo grading system,24 combining the SCV and CMAP data,
CTS is frequently associated with various systemic diseases, such as diabetes mellitus, hypothyroidism, chronic renal failure with long-term hemodialysis, rheumatoid arthritis, systemic lupus erythematosus, acromegaly, and gout. The etiology of CTS correlated with long-term hemodialysis would be attributed to ischemic neuropathy by steal phenomenon and chronic tenosynovitis by extensive b2 microglobulin amyloid deposition.4e8 The underlying factors, including local effect of arteriovenous fistula with edema and uremic polyneuropathy, are believed to increase the risk and contribute to more advanced symptoms of hemodialysis-related CTS.2e11 Considering the complex disease mechanism and progressively underlying polyneuropathy, it has been recognized that CTS caused by long-term hemodialysis is a more advanced and uncurable disease with active progression. The relatively limited postoperative improvement after carpal tunnel release and the high recurrence rate of CTS would be expected in these patients.4e8,11 In general consensus, patients who are refractory to nonsurgical treatment are suggested to receive surgical decompression of the carpal tunnel. For the patients associated with long-term hemodialysis, some authors
Table 2
Comparisons by HOS grading. N
Table 1
Patient demographics.
Sex, M/F Mean age (range) Duration of symptoms Mean follow-up time Complications ECTR failure and shift to open release
Idiopathic
HD
9/17 50.16 (34e76) 3.1 (2e6)
11/13 59.12 (43e70) 3.3 (2e6)
14.2 mo (range: 6e29 mo) 0% 0%
16 mo (range: 4e28 mo) 0% 8.3% (2/24)
Idio HD p
26 21
Pre-op
Post-op
Mean SD
Mean SD
2.27 0.60 2.95 1.20 0.037
0.65 0.80 1.43 0.93 0.002
p <0.001 <0.001
Statistical results from the Wilcoxon Signed Rank test show that both groups have significantly lower severity after ECTR. Results from the Mann-Whitney U test indicate that pre-op HOS grading showed significant pre-op and post-op differences between idiopathic and long-term hemodialysis with CTS groups. The long-term hemodialysis with CTS group showed higher grade of CTS severity both preoperatively and postoperatively. Idio Z idiopathic CTS group; HD Z long-term hemodialysis with CTS group.
ECTR in idiopathic and hemodialysis CTS patients Table 3 Comparision Questionnaire. N
by
Quick
Pre op Mean SD
Idio
HD
QD BQS BQF QD BQS BQF
26 26 26 22 22 22
23.41 2.36 1.77 40.29 2.58 2.29
17.94 0.77 0.73 28.80 1.03 1.12
DASH
and
Post op
15
p
N
Pre-op Mean SD
Post-op Mean SD
25 13
1.56 1.39 2.54 1.66
0.56 1.08 1.85 1.57
Mean SD 11.91 1.50 1.33 16.63 1.48 1.47
9.80 0.44 0.30 21.59 0.59 0.74
0.009 <0.001 0.005 0.003 0.001 0.006
Two aspects of questions: symptoms and functional status related for each group with the results before and after operation. The questionnaire scores were all significantly lower after ECTR in both groups. QD Z Quick DASH; BQS Z Boston Questionnaire symptomatic aspect questionnaire; BQF Z Boston Questionnaire functional related questionnaire. Statistics by Wilcoxon Signed Rank test.
prefer ECTR, but the others advocate pursuing OCTR or extensive OCTR as a standard approach. Nonetheless, there is still no randomized trial or well-established guideline for treating CTS with long-term hemodialysis. Theoretically, extended OCTR may have better visualization of the median nerve, and decompression along with thorough neurolysis and synovectomy are feasible with the open approach. However, the effectiveness with or without thorough neurolysis and synovectomy for symptomatic relief of the hemodialysis-related CTS is still controversial. Some reports even mentioned that extensive synovectomy or neurolysis are not necessarily indicated for every hemodialysis-related CTS patient.25 Moreover, the extensive procedures may increase the risk of short-term and long-term morbidities after the operation. ECTR was first described by Okutsu et al in 1989.12 The authors further reported the effectiveness and safety of ECTR in hemodialysis-related CTS and yielded similar results as in idiopathic CTS.9 Nonetheless, evidence comparing the effectiveness between ECTR and OCTR is
Table 4
Table 5 Comparison of electrodiagnostic grade from Christopher L. Hankins, 2007.
Boston
Idio HD
DSL DSL
usually limited to Level V reports, in which a minimum of self-reported questionnaires were included for the outcomes study. The outcomes of different surgical approaches were mostly evaluated and reported by the operative surgeons. Possible observation bias in reporting a true result could not be ruled out. Therefore a standardized measurement that demonstrates reproducibility and validity is necessary. In addition to the direct response from the patients in the clinics, we also chose the selfadministered questionnaire as one of our main assessment tools. Since Levine26 devised the CTS instrument in 1993, the application of a self-administered questionnaire has been emphasized and widely used. In this study, we employed the Boston questionnaire, and we also adopted the QuickDASH, for double evaluation. Ideally, if we could recruit enough patients of hemodialysis-related CTS, we would randomize the patients to compare ECTR and OCTR in the effectiveness of symptomatic relief. However, some hemodialysis-related CTS patients were referred by the patients of the Renal Club suffering from similar symptoms. They were prone to receive a similar endoscopic approach and declined recruitment into a randomized study. Therefore, we compared the effectiveness of ECTR between idiopathic and hemodialysis-related CTS patients instead. Although hemodialysis-related patients were supposed to be more severe when they were evaluated by the HOS and both questionnaires, both groups showed significant improvement after the surgery. In general, the postoperative HOS of hemodialysis-related patients was not as good as that of idiopathic patients. Nonetheless, there was no significant difference when they were evaluated by
Comparision by Quick DASH and Boston Questionnaire between idiopathic and long-term hemodialysis groups. Idio
QD BQ-S BQ-F
<0.001 0.328
Pre-op Post-op Pre-op Post-op Pre-op Post-op
N
Mean SD
26 26 26 26 26 26
23.41 11.91 2.36 1.50 1.77 1.33
17.94 9.80 0.77 0.44 0.73 0.30
HD Mean rank
N
Mean SD
19.96 24.06 22.88 24.21 21.08 24.27
22 22 22 22 22 22
40.29 16.63 2.58 1.48 2.29 1.47
28.80 21.59 1.03 0.59 1.12 0.74
p Mean rank 29.86 25.02 26.41 24.84 28.55 24.77
0.015 0.811 0.385 0.876 0.065 0.900
Preoperatively, the Quick DASH score was much higher in the HD group, in other words, the more advanced severity of CTS in the HD group was demonstrated. But after ECTR, there was no difference in the Quick DASH score between the two groups. With regard to the Boston Questionnaire score, the preoperative and postoperative data of both groups showed no statistically significant differences. QD Z Quick DASH; BQS Z Boston Questionnaire symptomatic aspect questionnaire; BQF Z Boston Questionnaire functional related questionnaire. Statistics by Mann-Whitney U test.
16 Table 6
S. Yu-Chen Ho, Y.-T. Lin Comparison of electrodiagnostic grade by Tokyo electrodiagnostic grading from Jun-ichi Iida, 2008. Idio
Pre Post
HD
p
N
Mean SD
Mean rank
N
Mean SD
Mean rank
25 25
1.50 0.76 1.29 0.61
11.71 10.82
13 13
2.08 1.04 2 0.91
16.46 17.42
0.097 0.021
The data showed similar grade of the two groups preoperatively but the grade of the HD group was much higher compared with the result of the idiopathic group after ECTR (mean SD: 2 0.91 vs. 1.29 0.61, p Z 0.021).
the postoperative questionnaires. From our point of view, the HOS included paresthesia, objective sensory deficit, force of thumb abduction, and status of thenar muscles. Even though the paresthesia might show considerable improvement subjectively, the sensory deficit, pinch power, and wasting of thenar muscle were not improved in 3 months. On the contrary, both questionnaires assessed the symptoms and functions of patients by the performance of daily activities. The evaluations are less likely to weigh on thenar muscle performance. The extent of improvement by the questionnaires might be significantly greater in the hemodialysis-related patients, but the extent of improvement by clinical evaluations might not be as significant. Subjectively, ECTR was effective in both groups of patients, but the severity of their preoperative status, especially with advanced involvement, may compromise the objective results. In our study, hemodialysis-related patients presented inferior electrophysiological results, even though they reported the satisfactory postoperative outcome by HOS and by the self-administered questionnaires. These patients are more susceptible to compression neuropathy because of their underlying uremic polyneuropathy. Theoretically, the electrophysiological findings could be correlated to the clinical results, and perhaps it could more objectively reflect the true relief of the entrapment from CTS. Contradictory results have been reported by a few studies, suggesting that the severity of electrophysiologic findings is not parallel to the subjective symptoms, especially for mild CTS patients.27,28 Moreover, in the cases of long-term hemodialysis, proximal invasion of uremic neuropathy has been reported by some studies when hemodialysis is for longer than 10 years.29 Most of our patients have had hemodialysis for longer than 10 years (81.8%). Therefore, even though we conducted the surgical relief of the carpal tunnel, proximal nerve function may still be progressively impaired.29 Although the results from the self-administered questionnaires and the electrophysiological findings are inconsistent in these hemodialysisrelated patients, it is possible to have satisfactory results in symptoms and questionnaires but with the less satisfactory electrophysiological outcome.30 The limitations of this study include a small sample size, no randomization, and shorter-term follow-up. These patients are more vulnerable to drop out from the study when they felt subjectively better. Nonetheless, a comparison of long-term effectiveness between the ECTR and OCTR would be of more interest to surgeons. A study of the long-term effectiveness of ECTR in hemodialysis-related CTS should be encouraged.
Acknowledgments The authors are grateful for the help of Miss Tseng HsiaoJung, Biostatistical Center for Clinical Research, Taoyuan, Taiwan.
References 1. Lin HH, Chen HT, Chen YC, Fang JT, Huang CC. Carpal tunnel syndrome in long-term hemodialysis patients. Acta Nephrologica. 2001;15:111e114. 2. Teitz CC, DeLisa JA, Halter SK. Results of carpal tunnel release in renal hemodialysis patients. Clin Orthop Rel Res. 1985;198: 197e200. 3. Gilbert MS, Robinson A, Baez A, et al. Carpal tunnel syndrome in patients who are receiving long-term hemodialysis. J Bone Joint Surg. 1988;70A:1145e1153. 4. Health Promotion Administration, Ministry of Health and Welfare. Available at: www.bhp.doh.gov.tw/ Accessed 14.02.2013. 5. Gejyo F, Odani S, Yamada T, et al. Beta 2-microglobulin: a new form of amyloid protein associated with chronic hemodialysis. Kidney Int. 1986;30:385e390. 6. Charra B, Calemard E, Laurent G. Chronic renal failure treatment duration and mode: their relevance to the late dialysis periarticular syndrome. Blood Purif. 1988;6:117e124. 7. Jadoul M. Dialysis-related amyloidosis: importance of biocompatibility and age. Nephrol Dial Transplant. 1998; 13(Suppl. 7):61e64. 8. Drueke TB, Zingraff J, Noe ¨l LH, Bardin T, Kuntz D. Amyloidosis and dialysis: pathophysiological aspects. Contr Nephrol. 1988; 62:60e66. 9. Okutsu I, Hamanaka I, Ninomiya S, Takatori Y, Shimizu K, Ugawa Y. Results of endoscopic management of carpal tunnel syndrome in long-term hemodialysis versus idiopathic patients. Nephrol Dial Transplant. 1993;8:1110e1114. 10. Kim SJ, Shin SJ, Kang ES. Endoscopic carpal tunnel release in patients receiving long-term hemodialysis. Clin Orthop Relat Res. 2000;376:141e148. 11. Wilson SW, Pollard RE, Lees VC. Management of carpal tunnel syndrome in renal dialysis patients using an extended carpal tunnel release procedure. J Plast Reconstr Aesthet Surg. 2008; 61:1090e1094. 12. Okutsu I, Ninomiya S, Takatori Y, Ugawa Y. Endoscopic management of carpal tunnel syndrome. Arthroscopy. 1989;5: 11e18. 13. Chow JC, Hantes ME. Endoscopic carpal tunnel release: thirteen years’ experience with the Chow technique. J Hand Surg Am. 2002;27:1011e1018. 14. Agee JM, McCarroll Jr HR, Tortosa RD, Berry DA, Szabo RM, Peimer CA. Endoscopic release of the carpal tunnel: a randomized prospective multicenter study. J Hand Surg Am. 1992; 17:987e995.
ECTR in idiopathic and hemodialysis CTS patients 15. Brown RA, Gelberman RH, Seiler III JG, et al. Carpal tunnel release. A prospective, randomized assessment of open and endoscopic methods. J Bone Joint Surg Am. 1993;75: 1265e1275. 16. Scholten RJPM, Mink van der Molen A, Uitdehaag BMJ, et al. Surgical treatment options for carpal tunnel syndrome. The Cochrane Library. 2012;3. 17. Giannini F, Cioni R, Mondelli M, et al. A new clinical scale of carpal tunnel syndrome: validation of the measurement and clinical-neurophysiological assessment. Clin Neurophysiol. 2002;113:71e77. 18. Menon J. Endoscopic carpal tunnel release: a single-portal technique. Contemp Orthop. 1993;26:109e116. 19. Mondelli M, Ginanneschi F, Rossi S, Reale F, Padua L, Giannini F. Inter-observer reproducibility and responsiveness of a clinical severity scale in surgically treated carpal tunnel syndrome. Acta Neurol Scand. 2002;106:263e268. 20. Katz JN, Simmons BP. Clinical practice. Carpal tunnel syndrome. N Engl J Med. 2002;346:1807e1812. 21. Liu YF, Lin GT, Lu YM, et al. Cross-cultural adaptation of the Chinese version of the Boston carpal tunnel questionnaire. Formos J Phys Ther. 2008;33:75e85 [Chinese]. 22. Beaton DE, Wright JG, Katz JN. Upper Extremity Collaborative Group. Development of the QuickDASH: comparison of the three item-reduction approaches. J Bone Joint Surg Am. 2005; 87:1038e1046. 23. Hankins CL, Brown MG, Lopez RA, Lee AK, Dang J, Harper RD. A 12-year experience using the Brown two-
17
24.
25.
26.
27.
28.
29.
30.
portal endoscopic procedure of transverse carpal ligament release in 14,722 patients: defining a new paradigm in the treatment of carpal tunnel syndrome. Plast Reconstr Surg. 2007;120:1911e1921. Iida J, Hirabayashi H, Nakase H, Sakaki T. Carpal tunnel syndrome: electrophysiological grading and surgical results by minimum incision open carpal tunnel release. Neurol Med Chir (Tokyo). 2008;48:554e559. Shiota E, Tsuchiya K, Yamaoka K, Kawoma O. Open carpal tunnel decompression in long-term haemodialysis patients. J Hand Surg Br. 2001;26:529e532. Levine DW, Simmons BP, Koris MJ, et al. A self-administered questionnaire for the assessment of severity of symptoms and functional status in carpal tunnel syndrome. J Bone Joint Surg Am. 1993;75:1585e1592. Chan L, Turner JA, Comstock BA, et al. The relationship between electrodiagnostic findings and patient symptoms and function in carpal tunnel syndrome. Arch Phys Med Rehabil. 2007;88:19e24. Dudley Porras AF, Rojo Alaminos P, Vinuales JI, Ruiz Villamanan MA. Value of electrodiagnostic tests in carpal tunnel syndrome. J Hand Surg Br. 2000;25:361e365. Hirasawa Y, Ogura T. Carpal tunnel syndrome in patients on long-term hemodialysis. Scand J Plast Reconstr Surg Hand Surg. 2000;34:373e381. Mondelli M, Reale F, Padua R, Aprile I, Padua L. Clinical and neurophysiological outcome of surgery in extreme carpal tunnel syndrome. Clin Neurophysiol. 2001;112:1237e1242.
Available online at www.sciencedirect.com
ScienceDirect journal homepage: www.e-fjs.com
ORIGINAL ARTICLE
Comparing the effectiveness of endoscopic carpal tunnel release between idiopathic and long-term hemodialysis patients Susan Yu-Chen Ho, Yu-Te Lin* Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Linkou, Taiwan Received 20 February 2013; received in revised form 7 March 2013; accepted 27 May 2013 Available online 30 December 2013
KEYWORDS Boston carpal tunnel questionnaire; carpal tunnel syndrome; endoscopic carpal tunnel release; hemodialysis; historical-objective scale; quickDASH questionnaire
Summary Background: Carpal tunnel syndrome (CTS) is recognized as an increasing morbidity in long-term hemodialysis patients. In general, the open method is the preferred technique of carpal tunnel release for most of the surgeons. Endoscopic carpal tunnel release (ECTR) is an alternative approach for idiopathic CTS, but its effectiveness for hemodialysisrelated patients is still under dispute. Objectives: The purpose of current study was to compare the effectiveness of ECTR in treating CTS between long-term hemodialysis patients and idiopathic patients. Methods: From November 2008 to March 2011, we consecutively collected 26 patients with idiopathic CTS and 22 long-term hemodialysis patients with CTS by a single surgeon. All patients received ECTR for decompression of the median nerve. The effectiveness between the two groups of patients was analyzed by clinical observation, historical-objective scale, two kinds of self-administered questionnaires (QuickDASH and Boston carpal tunnel questionnaires), and objectively by electrophysiological evaluation preoperatively and 3 months postoperatively. Results: With regard to the historical-objective scale, the hemodialysis group had significantly more severe grades than the idiopathic group in preoperative and postoperative evaluations. Both groups showed significant improvement after the ECTR. According to the selfadministered questionnaire results, there was no significant difference of the effectiveness of ECTR between the groups. Hemodialysis-related CTS was found to have more advanced
Conflicts of interest: The authors declare no conflicts of interest. * Corresponding author. Division of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, 5, Fu-Hsin Street, Kweishan, Taoyuan, Taiwan. E-mail address: [email protected] (Y.-T. Lin). 1682-606X/$ - see front matter Copyright ª 2013, Taiwan Surgical Association. Published by Elsevier Taiwan LLC. All rights reserved. http://dx.doi.org/10.1016/j.fjs.2013.05.007
12
S. Yu-Chen Ho, Y.-T. Lin electrophysiologic findings, and no significant improvement of electrophysiologic grading can be recognized in this group of patients. Conclusion: ECTR was effective in both groups of patients, but the severity of their preoperative status, especially with advanced involvement, may compromise the objective results. Although the results from the self-administered questionnaires and the electrophysiological findings were inconsistent in these hemodialysis-related patients, it is possible to have satisfactory results in symptoms and questionnaires but with the less satisfactory electrophysiological outcome. Copyright ª 2013, Taiwan Surgical Association. Published by Elsevier Taiwan LLC. All rights reserved.
1. Introduction
2. Materials and methods
Carpal tunnel syndrome (CTS) is the most common compression neuropathy of the upper extremity, and it accounts for 90% of all entrapment neuropathies.1,2 The typical symptoms of CTS include paresthesia, tingling sensation and/or pain on the palmar surface of the radial digits, and even motor weakness and signs of thenar muscle atrophy in an advanced disease.1e3 From a recent review by the Bureau of Health Promotion Department of Health, Taiwan, R.O.C., the incidence and prevalence of hemodialysis patients increased annually in Taiwan.4 Chronic renal failure has been recognized as one of the risk factors of CTS, and the risk increases annually in terms of duration of hemodialysis. Pathogenesis of the amyloid fibrils in the carpal tunnel was documented in 1986.5 Investigations found that one-third of chronic hemodialysis patients suffered CTS after <4 years of dialysis, a percentage that increased remarkably after 5 years, and reached nearly 100% after 20 years.6e8 In general, most surgeons prefer an open carpal tunnel release (OCTR) for long-term hemodialysis patients. The disease complexity and its progressive process were the major concerns by the surgeons when choosing the surgical technique.1e3,9,10 Nonetheless, OCTR may induce several morbidities, such as postoperative edema, bleeding, hypertrophic scar formation, infections, nerve injuries, and subsequently causes long periods of restriction of postoperative daily activities.9e11 The first endoscopic carpal tunnel release (ECTR) was described by Okutsu et al in 1989,12 and endoscopic decompression has been applied to idiopathic or any other secondary carpal tunnel syndrome ever since as a main competitor of the traditional OCTR procedure. Studies comparing OCTR and ECTR have generally concluded that, with its advantages of reduced scar pain, preservation of grip and pinch strength, and early return to work, ECTR is the beneficial application for CTS patients.12e15 The effectiveness of both procedures in idiopathic CTS patients appears to be equivalent and thus the ECTR has become a popular alternative carpal tunnel release method.16,17 However, there are not many reports discussing the efficacy of ECTR in terms of treating CTS patients with long-term hemodialysis. The purpose of the current study was to compare the effectiveness of ECTR in treating CTS between long-term hemodialysis patients and idiopathic patients.
The study was approved by the Institutional Review Board of Chang Gung Memorial Hospital, Taoyuan, Taiwan. From November 2008 to March 2011, we consecutively collected 26 patients with idiopathic CTS and 22 long-term hemodialysis patients with CTS by a single surgeon (Y.-T.L.).
2.1. Inclusion and exclusion criteria We excluded patients with risk factors of diabetes mellitus, rheumatoid arthritis, gout, and hypothyroidism. Patients with a past history of hand and wrist trauma were also excluded. Most of the patients were referred by neurologists. The diagnosis of CTS was mainly established by the typical signs and symptoms. Electrophysiology study was arranged for every patient pre- and postoperatively.
2.2. Surgical indications The surgical indications are based on the patient’s occupation, severity of clinical symptoms, advanced disease by nerve conduction tests, electrodiagnostic evidence of axon degeneration of the abductor pollicis brevis muscle, or a combination of these elements.
2.3. Operative procedures We used the CTS Relief Kit (ConMed Linvatec Biomaterials, Largo, FL, USA) and a 2.7-mm video assisted 0 endoscope for single portal ECTR (Menon’s technique).18 All surgeries were performed on an outpatient basis. The patient was placed in a supine position with the upper limb abducted on a hand table. Local anesthesia with 1% lidocaine was used to infiltrate the operative field. When there was an arterovenous fistula on the distal forearm and a rubber tourniquet could not be applied, diluted epinephrine (1:100,000) was added into the narcotics. For idiopathic patients, a rubber tourniquet was applied before incision. A 1-cm incision was made around the distal forearm crease ulnarly to the palmaris longus tendon. The incision was deepened to the antebrachial fascia. A small window was opened on the fascia. A freer was used to sound the carpal tunnel. Dilators of 5.5 mm and 7 mm were used to enlarge the carpal tunnel. A grooved cannula was then introduced
ECTR in idiopathic and hemodialysis CTS patients into the tunnel, and the transverse carpal ligament (TCL) could be observed through the endoscope. The TCL was transected by the endoscopic scalpel from proximal to distal. Complete division of the TCL was confirmed by observing fat dropping into the cannula at the proximal tunnel and observation of overlying muscle fibers at the middle and distal tunnel. Then the incision wound was closed. The average operation time was <15 minutes.
2.4. Postoperative care After the surgery, the patients were followed-up on the 2nd postoperative day, and after 1 month, 3 months, and 6 months. Dressings were changed on the 2nd day, and rehabilitation programs including massage and active range of motion were initiated at the same time. Offload of the hand for the 1st month was informed to the patient, and motorcycle riding was prohibited during this period.
2.5. Subjective and objective measurements The effectiveness between the two groups of patients was analyzed by clinical observation, historical-objective scale (HOS),19,20 two kinds of self-administered questionnaires [Boston carpal tunnel (BQ)21 and a short version of the disability of arm, shoulder, and hand questionnaire (QuickDASH)22] and objectively by electrophysiological evaluation preoperatively and 3 months postoperatively.
2.6. HOS Clinical assessment of the severity of CTS was made by using a 5-point clinical HOS. This scale includes any kind of paresthesia (night or day), objective sensory deficit, force of thumb abduction, and status of thenar muscles. A higher grade represents a greater severity of CTS.
13 median nerve and ulnar nerve. The amplitudes of sensory action potentials and compound muscle action potentials (CMAPs) were also measured. We then collected the DSL data and divided it into four grades according to the electrodiagnostic grade by Hankins et al.23 (Grade I, DSL: 3.7e4.19 ms, Grade II, DSL: 4.2e4.9 ms, Grade III, DSL: 5.0e7.0 ms, Grade IV, DSL: >7.0 ms.). For better confirmation, we also collected SCV and CMAP data and divided these into four grades according to the Tokyo electrodiagnostic grading of Iida et al24 (normal data: SCV 45 m/ s, CMAP 6 mV; mild: SCV < 45 m/s, CMAP 6 mV; moderate: SCV < 45 m/s, CMAP < 6 mV; severe: no sensory response).
2.10. Study protocol All the measurements were arranged at three time points as illustrated in Fig. 1. At the preoperative clinic, 3 months and 6 months after the operation, we evaluated the patients with two aspects: (1) subjectively, the clinical symptoms/signs, and complications and more specifically we graded it with HOS; and (2) objectively, we collected the preoperative and postoperative patient-oriented questionnaires (BQ and QuickDASH) and electrophysiologic studies.
2.11. Statistical analysis We used SPSS version 17 (SPSS Inc., Chicago, IL, USA) and nonparametric tests were employed for a limited case number. Wilcoxon signed rank test was used to compare HOS, electrophysiological grading (two grading systems), and questionnaire scores prior to and after the operation in each group. The ManneWhitney U test was applied to evaluate the differences of scores between the two groups at preoperative and postoperative time points. A pvalue < 0.05 was considered statistically significant.
2.7. BQ
3. Results For subjective evaluation of the severity of symptoms, the BQ (the validated Chinese version) was answered by patients. The questionnaire is divided into two parts: symptoms (11 items) and functional status (8 items). A higher score indicated a more severe impairment.
2.8. QuickDASH From the original DASH, a shorter version, the 11-item QuickDASH, was developed. Each item has five response options and, from the item scores, scale scores are calculated, ranging from 0 (no disability) to 100 (most severe disability). The validated Chinese version of QuickDASH was answered by patients.
2.9. Electrophysiologic study Neurophysiologic examination was performed by neurologists in our institute, which included a complete sensory conduction velocity (SCV) and motor conduction velocity, distal motor latency, and distal sensory latency (DSL) of the
The baseline conditions of the two patient groups are compared in Table 1. Basically, two comparable patient groups existed, except for the greater age of the hemodialysis group. No surgical complications, including nerve damage, hematoma, and wound infection, were noted in both groups. Symptoms of two patients in the hemodialysis group failed to respond to ECTR during the follow-up examinations. Extensive OCTR and neurolysis of the median nerve from the distal forearm to the palm was performed. Both patients reported partial relief of their symptoms thereafter.
3.1. HOS More than 90% of patients were noted with significant relief of pain and paresthesia on the 2nd day after the operation. In more than 95% of patients, the symptoms improved with time during the follow-ups. With regard to the HOS, the hemodialysis group had significantly more severe grades than the idiopathic group in preoperative and postoperative
14
S. Yu-Chen Ho, Y.-T. Lin
Figure 1
The study protocol.
evaluations. Both groups showed significant improvement after the ECTR (Table 2).
3.2. BQ and QuickDASH
showed less satisfactory results of hemodialysis patients after ECTR, which was statistically significant (Table 6).
4. Discussion
With regard to the evaluations by both questionnaires, neither the idiopathic group nor the hemodialysis group revealed significant improvement after ECTR (Table 3). Furthermore, when we compared the preoperative and postoperative conditions of the two groups (Table 4), the QuickDASH displayed the more advanced preoperative status of the hemodialysis group (p Z 0.015). While comparing the postoperative results of the QuickDASH, no significant difference was found between the two groups (p Z 0.811). By contrast, the BQ exhibited no difference in the disease status of the two groups preoperatively. Both groups of patients revealed similar improvement after ECTR by BQ, in both symptoms and functional status. Therefore, according to the self-administered questionnaire results, there was no significant difference in the effectiveness of ECTR between the groups.
3.3. Electrophysiological study Two grading systems were employed to measure the electrophysiological results. The Hankins grading system23 based on DSL data showed a significant improvement of the idiopathic patients after ECTR (p < 0.001), while there were limited changes in electrophysiological data of the hemodialysis patients postoperatively (Table 5). The Tokyo grading system,24 combining the SCV and CMAP data,
CTS is frequently associated with various systemic diseases, such as diabetes mellitus, hypothyroidism, chronic renal failure with long-term hemodialysis, rheumatoid arthritis, systemic lupus erythematosus, acromegaly, and gout. The etiology of CTS correlated with long-term hemodialysis would be attributed to ischemic neuropathy by steal phenomenon and chronic tenosynovitis by extensive b2 microglobulin amyloid deposition.4e8 The underlying factors, including local effect of arteriovenous fistula with edema and uremic polyneuropathy, are believed to increase the risk and contribute to more advanced symptoms of hemodialysis-related CTS.2e11 Considering the complex disease mechanism and progressively underlying polyneuropathy, it has been recognized that CTS caused by long-term hemodialysis is a more advanced and uncurable disease with active progression. The relatively limited postoperative improvement after carpal tunnel release and the high recurrence rate of CTS would be expected in these patients.4e8,11 In general consensus, patients who are refractory to nonsurgical treatment are suggested to receive surgical decompression of the carpal tunnel. For the patients associated with long-term hemodialysis, some authors
Table 2
Comparisons by HOS grading. N
Table 1
Patient demographics.
Sex, M/F Mean age (range) Duration of symptoms Mean follow-up time Complications ECTR failure and shift to open release
Idiopathic
HD
9/17 50.16 (34e76) 3.1 (2e6)
11/13 59.12 (43e70) 3.3 (2e6)
14.2 mo (range: 6e29 mo) 0% 0%
16 mo (range: 4e28 mo) 0% 8.3% (2/24)
Idio HD p
26 21
Pre-op
Post-op
Mean SD
Mean SD
2.27 0.60 2.95 1.20 0.037
0.65 0.80 1.43 0.93 0.002
p <0.001 <0.001
Statistical results from the Wilcoxon Signed Rank test show that both groups have significantly lower severity after ECTR. Results from the Mann-Whitney U test indicate that pre-op HOS grading showed significant pre-op and post-op differences between idiopathic and long-term hemodialysis with CTS groups. The long-term hemodialysis with CTS group showed higher grade of CTS severity both preoperatively and postoperatively. Idio Z idiopathic CTS group; HD Z long-term hemodialysis with CTS group.
ECTR in idiopathic and hemodialysis CTS patients Table 3 Comparision Questionnaire. N
by
Quick
Pre op Mean SD
Idio
HD
QD BQS BQF QD BQS BQF
26 26 26 22 22 22
23.41 2.36 1.77 40.29 2.58 2.29
17.94 0.77 0.73 28.80 1.03 1.12
DASH
and
Post op
15
p
N
Pre-op Mean SD
Post-op Mean SD
25 13
1.56 1.39 2.54 1.66
0.56 1.08 1.85 1.57
Mean SD 11.91 1.50 1.33 16.63 1.48 1.47
9.80 0.44 0.30 21.59 0.59 0.74
0.009 <0.001 0.005 0.003 0.001 0.006
Two aspects of questions: symptoms and functional status related for each group with the results before and after operation. The questionnaire scores were all significantly lower after ECTR in both groups. QD Z Quick DASH; BQS Z Boston Questionnaire symptomatic aspect questionnaire; BQF Z Boston Questionnaire functional related questionnaire. Statistics by Wilcoxon Signed Rank test.
prefer ECTR, but the others advocate pursuing OCTR or extensive OCTR as a standard approach. Nonetheless, there is still no randomized trial or well-established guideline for treating CTS with long-term hemodialysis. Theoretically, extended OCTR may have better visualization of the median nerve, and decompression along with thorough neurolysis and synovectomy are feasible with the open approach. However, the effectiveness with or without thorough neurolysis and synovectomy for symptomatic relief of the hemodialysis-related CTS is still controversial. Some reports even mentioned that extensive synovectomy or neurolysis are not necessarily indicated for every hemodialysis-related CTS patient.25 Moreover, the extensive procedures may increase the risk of short-term and long-term morbidities after the operation. ECTR was first described by Okutsu et al in 1989.12 The authors further reported the effectiveness and safety of ECTR in hemodialysis-related CTS and yielded similar results as in idiopathic CTS.9 Nonetheless, evidence comparing the effectiveness between ECTR and OCTR is
Table 4
Table 5 Comparison of electrodiagnostic grade from Christopher L. Hankins, 2007.
Boston
Idio HD
DSL DSL
usually limited to Level V reports, in which a minimum of self-reported questionnaires were included for the outcomes study. The outcomes of different surgical approaches were mostly evaluated and reported by the operative surgeons. Possible observation bias in reporting a true result could not be ruled out. Therefore a standardized measurement that demonstrates reproducibility and validity is necessary. In addition to the direct response from the patients in the clinics, we also chose the selfadministered questionnaire as one of our main assessment tools. Since Levine26 devised the CTS instrument in 1993, the application of a self-administered questionnaire has been emphasized and widely used. In this study, we employed the Boston questionnaire, and we also adopted the QuickDASH, for double evaluation. Ideally, if we could recruit enough patients of hemodialysis-related CTS, we would randomize the patients to compare ECTR and OCTR in the effectiveness of symptomatic relief. However, some hemodialysis-related CTS patients were referred by the patients of the Renal Club suffering from similar symptoms. They were prone to receive a similar endoscopic approach and declined recruitment into a randomized study. Therefore, we compared the effectiveness of ECTR between idiopathic and hemodialysis-related CTS patients instead. Although hemodialysis-related patients were supposed to be more severe when they were evaluated by the HOS and both questionnaires, both groups showed significant improvement after the surgery. In general, the postoperative HOS of hemodialysis-related patients was not as good as that of idiopathic patients. Nonetheless, there was no significant difference when they were evaluated by
Comparision by Quick DASH and Boston Questionnaire between idiopathic and long-term hemodialysis groups. Idio
QD BQ-S BQ-F
<0.001 0.328
Pre-op Post-op Pre-op Post-op Pre-op Post-op
N
Mean SD
26 26 26 26 26 26
23.41 11.91 2.36 1.50 1.77 1.33
17.94 9.80 0.77 0.44 0.73 0.30
HD Mean rank
N
Mean SD
19.96 24.06 22.88 24.21 21.08 24.27
22 22 22 22 22 22
40.29 16.63 2.58 1.48 2.29 1.47
28.80 21.59 1.03 0.59 1.12 0.74
p Mean rank 29.86 25.02 26.41 24.84 28.55 24.77
0.015 0.811 0.385 0.876 0.065 0.900
Preoperatively, the Quick DASH score was much higher in the HD group, in other words, the more advanced severity of CTS in the HD group was demonstrated. But after ECTR, there was no difference in the Quick DASH score between the two groups. With regard to the Boston Questionnaire score, the preoperative and postoperative data of both groups showed no statistically significant differences. QD Z Quick DASH; BQS Z Boston Questionnaire symptomatic aspect questionnaire; BQF Z Boston Questionnaire functional related questionnaire. Statistics by Mann-Whitney U test.
16 Table 6
S. Yu-Chen Ho, Y.-T. Lin Comparison of electrodiagnostic grade by Tokyo electrodiagnostic grading from Jun-ichi Iida, 2008. Idio
Pre Post
HD
p
N
Mean SD
Mean rank
N
Mean SD
Mean rank
25 25
1.50 0.76 1.29 0.61
11.71 10.82
13 13
2.08 1.04 2 0.91
16.46 17.42
0.097 0.021
The data showed similar grade of the two groups preoperatively but the grade of the HD group was much higher compared with the result of the idiopathic group after ECTR (mean SD: 2 0.91 vs. 1.29 0.61, p Z 0.021).
the postoperative questionnaires. From our point of view, the HOS included paresthesia, objective sensory deficit, force of thumb abduction, and status of thenar muscles. Even though the paresthesia might show considerable improvement subjectively, the sensory deficit, pinch power, and wasting of thenar muscle were not improved in 3 months. On the contrary, both questionnaires assessed the symptoms and functions of patients by the performance of daily activities. The evaluations are less likely to weigh on thenar muscle performance. The extent of improvement by the questionnaires might be significantly greater in the hemodialysis-related patients, but the extent of improvement by clinical evaluations might not be as significant. Subjectively, ECTR was effective in both groups of patients, but the severity of their preoperative status, especially with advanced involvement, may compromise the objective results. In our study, hemodialysis-related patients presented inferior electrophysiological results, even though they reported the satisfactory postoperative outcome by HOS and by the self-administered questionnaires. These patients are more susceptible to compression neuropathy because of their underlying uremic polyneuropathy. Theoretically, the electrophysiological findings could be correlated to the clinical results, and perhaps it could more objectively reflect the true relief of the entrapment from CTS. Contradictory results have been reported by a few studies, suggesting that the severity of electrophysiologic findings is not parallel to the subjective symptoms, especially for mild CTS patients.27,28 Moreover, in the cases of long-term hemodialysis, proximal invasion of uremic neuropathy has been reported by some studies when hemodialysis is for longer than 10 years.29 Most of our patients have had hemodialysis for longer than 10 years (81.8%). Therefore, even though we conducted the surgical relief of the carpal tunnel, proximal nerve function may still be progressively impaired.29 Although the results from the self-administered questionnaires and the electrophysiological findings are inconsistent in these hemodialysisrelated patients, it is possible to have satisfactory results in symptoms and questionnaires but with the less satisfactory electrophysiological outcome.30 The limitations of this study include a small sample size, no randomization, and shorter-term follow-up. These patients are more vulnerable to drop out from the study when they felt subjectively better. Nonetheless, a comparison of long-term effectiveness between the ECTR and OCTR would be of more interest to surgeons. A study of the long-term effectiveness of ECTR in hemodialysis-related CTS should be encouraged.
Acknowledgments The authors are grateful for the help of Miss Tseng HsiaoJung, Biostatistical Center for Clinical Research, Taoyuan, Taiwan.
References 1. Lin HH, Chen HT, Chen YC, Fang JT, Huang CC. Carpal tunnel syndrome in long-term hemodialysis patients. Acta Nephrologica. 2001;15:111e114. 2. Teitz CC, DeLisa JA, Halter SK. Results of carpal tunnel release in renal hemodialysis patients. Clin Orthop Rel Res. 1985;198: 197e200. 3. Gilbert MS, Robinson A, Baez A, et al. Carpal tunnel syndrome in patients who are receiving long-term hemodialysis. J Bone Joint Surg. 1988;70A:1145e1153. 4. Health Promotion Administration, Ministry of Health and Welfare. Available at: www.bhp.doh.gov.tw/ Accessed 14.02.2013. 5. Gejyo F, Odani S, Yamada T, et al. Beta 2-microglobulin: a new form of amyloid protein associated with chronic hemodialysis. Kidney Int. 1986;30:385e390. 6. Charra B, Calemard E, Laurent G. Chronic renal failure treatment duration and mode: their relevance to the late dialysis periarticular syndrome. Blood Purif. 1988;6:117e124. 7. Jadoul M. Dialysis-related amyloidosis: importance of biocompatibility and age. Nephrol Dial Transplant. 1998; 13(Suppl. 7):61e64. 8. Drueke TB, Zingraff J, Noe ¨l LH, Bardin T, Kuntz D. Amyloidosis and dialysis: pathophysiological aspects. Contr Nephrol. 1988; 62:60e66. 9. Okutsu I, Hamanaka I, Ninomiya S, Takatori Y, Shimizu K, Ugawa Y. Results of endoscopic management of carpal tunnel syndrome in long-term hemodialysis versus idiopathic patients. Nephrol Dial Transplant. 1993;8:1110e1114. 10. Kim SJ, Shin SJ, Kang ES. Endoscopic carpal tunnel release in patients receiving long-term hemodialysis. Clin Orthop Relat Res. 2000;376:141e148. 11. Wilson SW, Pollard RE, Lees VC. Management of carpal tunnel syndrome in renal dialysis patients using an extended carpal tunnel release procedure. J Plast Reconstr Aesthet Surg. 2008; 61:1090e1094. 12. Okutsu I, Ninomiya S, Takatori Y, Ugawa Y. Endoscopic management of carpal tunnel syndrome. Arthroscopy. 1989;5: 11e18. 13. Chow JC, Hantes ME. Endoscopic carpal tunnel release: thirteen years’ experience with the Chow technique. J Hand Surg Am. 2002;27:1011e1018. 14. Agee JM, McCarroll Jr HR, Tortosa RD, Berry DA, Szabo RM, Peimer CA. Endoscopic release of the carpal tunnel: a randomized prospective multicenter study. J Hand Surg Am. 1992; 17:987e995.
ECTR in idiopathic and hemodialysis CTS patients 15. Brown RA, Gelberman RH, Seiler III JG, et al. Carpal tunnel release. A prospective, randomized assessment of open and endoscopic methods. J Bone Joint Surg Am. 1993;75: 1265e1275. 16. Scholten RJPM, Mink van der Molen A, Uitdehaag BMJ, et al. Surgical treatment options for carpal tunnel syndrome. The Cochrane Library. 2012;3. 17. Giannini F, Cioni R, Mondelli M, et al. A new clinical scale of carpal tunnel syndrome: validation of the measurement and clinical-neurophysiological assessment. Clin Neurophysiol. 2002;113:71e77. 18. Menon J. Endoscopic carpal tunnel release: a single-portal technique. Contemp Orthop. 1993;26:109e116. 19. Mondelli M, Ginanneschi F, Rossi S, Reale F, Padua L, Giannini F. Inter-observer reproducibility and responsiveness of a clinical severity scale in surgically treated carpal tunnel syndrome. Acta Neurol Scand. 2002;106:263e268. 20. Katz JN, Simmons BP. Clinical practice. Carpal tunnel syndrome. N Engl J Med. 2002;346:1807e1812. 21. Liu YF, Lin GT, Lu YM, et al. Cross-cultural adaptation of the Chinese version of the Boston carpal tunnel questionnaire. Formos J Phys Ther. 2008;33:75e85 [Chinese]. 22. Beaton DE, Wright JG, Katz JN. Upper Extremity Collaborative Group. Development of the QuickDASH: comparison of the three item-reduction approaches. J Bone Joint Surg Am. 2005; 87:1038e1046. 23. Hankins CL, Brown MG, Lopez RA, Lee AK, Dang J, Harper RD. A 12-year experience using the Brown two-
17
24.
25.
26.
27.
28.
29.
30.
portal endoscopic procedure of transverse carpal ligament release in 14,722 patients: defining a new paradigm in the treatment of carpal tunnel syndrome. Plast Reconstr Surg. 2007;120:1911e1921. Iida J, Hirabayashi H, Nakase H, Sakaki T. Carpal tunnel syndrome: electrophysiological grading and surgical results by minimum incision open carpal tunnel release. Neurol Med Chir (Tokyo). 2008;48:554e559. Shiota E, Tsuchiya K, Yamaoka K, Kawoma O. Open carpal tunnel decompression in long-term haemodialysis patients. J Hand Surg Br. 2001;26:529e532. Levine DW, Simmons BP, Koris MJ, et al. A self-administered questionnaire for the assessment of severity of symptoms and functional status in carpal tunnel syndrome. J Bone Joint Surg Am. 1993;75:1585e1592. Chan L, Turner JA, Comstock BA, et al. The relationship between electrodiagnostic findings and patient symptoms and function in carpal tunnel syndrome. Arch Phys Med Rehabil. 2007;88:19e24. Dudley Porras AF, Rojo Alaminos P, Vinuales JI, Ruiz Villamanan MA. Value of electrodiagnostic tests in carpal tunnel syndrome. J Hand Surg Br. 2000;25:361e365. Hirasawa Y, Ogura T. Carpal tunnel syndrome in patients on long-term hemodialysis. Scand J Plast Reconstr Surg Hand Surg. 2000;34:373e381. Mondelli M, Reale F, Padua R, Aprile I, Padua L. Clinical and neurophysiological outcome of surgery in extreme carpal tunnel syndrome. Clin Neurophysiol. 2001;112:1237e1242.