Carpal Tunnel Syndrome: No-Stitch Endoscopic Surgery as a Treatment Option by Scott R. Gibbs, MD, Kyle O. Colle, DO, & Christine M.

Transcription

1 Scientific Carpal Tunnel Syndrome: No-Stitch Endoscopic Surgery as a Treatment Option by Scott R. Gibbs, MD, Kyle O. Colle, DO, & Christine M. Byrd, MSN Since the 1980s, CTS has become one of the most prevalent work-related injuries. Scott R. Gibbs, MD, FACS, MSMA member since 1997, is the founder of the Brain and NeuroSpine Clinic of Missouri. He is currently the Division Chief of Neurosurgery and the Director of the Regional Brain and Spine Center at Southeast Missouri Hospital in Cape Girardeau. Kyle O. Colle, DO, MSMA member since 2009, is also a neurosurgeon at the clinic and on staff at SEMO Hospital. Contact: mmcneely@brainandneurospine.com Abstract Carpal tunnel syndrome (CTS) is the most common nerve entrapment disorder causing considerable discomfort, activity limitations and even a change in occupation. Appropriate medical and surgical treatment can interrupt the progression of the syndrome and avoid permanent disability. We report here a case of a woman who was unable to work because of persistent CTS. Her disabling symptoms were completely resolved and she was able to return to work after a successful endoscopic carpal tunnel release. Introduction Carpal tunnel syndrome is the most common peripheral entrapment neuropathy encountered by health care providers. The syndrome is estimated to affect about 1-3% of the adult population, but may occur in up to 10% of high-risk populations. 1,2 It is three times more common in women than in men. 3 CTS can result in pain, restrictions in daily activities, lost time from work and significant health care costs. Since the 1980s, there has been a six fold increase in the diagnosis of CTS and it is one of the most prevalent work-related injuries. 4 Pathophysiology and Clinical Presentation The carpal tunnel is an anatomic passageway bounded dorsally and laterally by the carpal bones and on the palmar surface by the transverse carpal ligament. Nine digital flexor tendons as well as the median nerve pass through this tunnel. 5 Carpal tunnel syndrome results from compression of the median nerve within this tunnel, beneath the transverse carpal ligament. The tissue pressure in the tunnel is much higher in patients with CTS than in patients without CTS, and the pressures are raised by wrist flexion and extension, and finger flexion. The nerve becomes entrapped, essentially resulting in a mini-compartment syndrome within the carpal tunnel. 6 The classic symptoms of carpal tunnel syndrome are pain and paresthesia in the median nerve distribution. However, some patients complain of symptoms in all digits of the affected hand. The symptoms are typically worse at night or during repetitive activities involving the hand. Patients may report being awakened at night with pain and paresthesia, which in severe cases can lead to sleep deprivation. The symptoms may also be exacerbated while doing routine daily activities, such as driving, using the telephone or keyboarding. To relieve the symptoms, 107:2 Missouri Medicine March/April

2 patients will often shake their hands or flick their wrists, as if shaking down a thermometer (flick sign). 3 The symptoms are often described as ascending from the hand, and they may radiate to the forearm; approximately 5% of the patients may even have pain radiate to the shoulder. In severe cases, they will develop decreased grip strength and thenar muscle atrophy. While CTS most often occurs in the dominant hand, it is bilateral in 55-65% of the cases. 6 Risk Factors Carpal tunnel syndrome has often been associated with repetitive motion activities of the wrist, as well as forceful grasping and vibration. Work-related CTS is significantly higher in workers who report frequent bending and twisting at the wrist or the use of vibrating hand tools. Occupations with high prevalence include mail delivery, meat cutters, health care work and assembly work in factories. 7 Although computer use is commonly thought to increase the risk of CTS, the studies have not been conclusive. It seems reasonable, however, to counsel patients about avoiding frequent, intensive keyboard and mouse use. 8 Other etiologies for development of CTS include metabolic conditions, such as hypothyroidism, diabetes, rheumatoid arthritis, gout, and vitamin deficiency. Additional risk factors believed to be associated with CTS are gender (more common in women), advanced age, smoking, alcohol, caffeine, and obesity. 6 Some women develop CTS during pregnancy, usually noted during the first trimester, and the symptoms are often bilateral. These patients should be treated conservatively, as the symptoms usually subside after delivery. 3 Diagnosis The diagnosis of carpal tunnel syndrome is made by a careful medical history and physical examination, and it is confirmed by electrophysiological studies. The clinical examination should include a careful inspection of the hands, evaluating for thenar atrophy. The sensory assessment consists of evaluating for hypesthesia, particularly in the hands. The loss of superficial sensation affects the palmar aspect of the thumb, index, and middle fingers and may split the ring finger. 10 Two-point discrimination may also be diminished in the same distribution. The motor examination may reveal weakness in the abductor and flexor pollicis brevis as well as the opponens pollicis (weakness in abducting and opposing the thumb), and flexor digitorum profundus weakness (weakness in flexing the second and third digits). Patients may describe clumsiness of the hand or difficulty with fine motor skills, which is usually due to loss of sensation rather than a motor deficit. Clinical tests for carpal tunnel syndrome include Phalen s test, Tinel s sign and the manual carpal compression test. Phalen s test is performed by flexing the wrist to 90 degrees for a full minute. It is considered positive if sensory symptoms are elicited in the median nerve distribution. Tinel s sign is positive if percussion over the carpal tunnel at the wrist produces sensory symptoms. Patients sometimes report a shock-like sensation radiating into the hand or forearm with this test. The carpal compression test consists of applying focal pressure over the volar aspect of the carpal tunnel to induce sensory symptoms in the distribution of the median nerve. Both Phalen s test and Tinel s sign may be less reliable in advanced CTS. 6 Electrodiagnostic studies, specifically electromyogram (EMG) and nerve conduction velocity (NCV) confirm the diagnosis and location of a median nerve entrapment neuropathy. EMG/NCV studies can also help distinguish CTS from other conditions, such as cervical radiculopathy and tendonitis. Since the specificity and sensitivity of these studies varies widely in the literature, normal electrophysiological testing does not preclude a diagnosis of CTS. 10 The differential diagnosis of hand paresthesia and discomfort includes cervical radiculopathy, ulnar neuropathy, tendonitis, peripheral neuropathy, osteoarthritis and Raynaud s phenomenon. Some patients may exhibit signs of doublecrush syndrome, which is a term referring to coexisting proximal and peripheral nerve compression. 11 The symptoms of cervical radiculopathy, particularly at the C6 and C7 nerve roots, and the symptoms of CTS can overlap, making it difficult sometimes to determine the location of the nerve entrapment. Cervical imaging and EMG/NCV studies can be helpful in directing an appropriate treatment plan. 11 Non-Surgical Treatment Options It is generally recommended that a conservative, non-surgical approach should be attempted as the preferred primary treatment of CTS, particularly in mild to moderate cases. Wrist Splints Splinting is often used as a first line treatment for CTS, either alone or in combination with anti-inflammatory medications. The most common types are the cock-up splint and neutral wrist supports. 5 In patients with mild to moderate CTS, the use 120 March/April :2 Missouri Medicine

3 Figures 1 and 2 The traditional open carpal tunnel release (OCTR) procedure consists of a long, palmar curvilinear incision to divide the transverse carpal ligament. clinical trials have established the efficacy of steroids injected into the carpal tunnel. 12,19-21 Steroid injections provide significant clinical improvement for about one month after injection. There is some evidence that relief may last longer than one month, but long-term clinical improvement has not been clearly established. It appears that patients with mild to moderate CTS are more likely to obtain long-term relief than patients with more severe CTS. 5 This must be done with extreme caution as inadvertent intraneural injection and intra-arterial injection has occurred. of wrist splints, worn consistently at night, has been shown to provide relief of CTS symptoms and improvement of sensory and motor conduction velocities in the long-term. 5,12-15 Oral Medications Oral anti-inflammatory medications are often used in an effort to decrease joint and tendon sheath edema that may compress the median nerve within the carpal tunnel. Although non-steroidal antiinflammatory medications (NSAIDS) are commonly used, there is limited data regarding their effectiveness. The few studies available have not shown a significant improvement in symptoms with NSAIDS over placebo. 13,14 A day course of oral steroids, however, has shown to provide significant short-term benefit in treating symptomatic CTS Courses of steroids longer than two weeks have not shown increased benefit. 17 Steroid Injections Local corticosteroid injection is a common non-surgical treatment for carpal tunnel syndrome, and Other Non-Surgical Options A variety of other therapies have been utilized over the years for treating CTS. There is some evidence of short-term benefit from ultrasound treatment, yoga and carpal bone mobilization. 22,23 The current literature does not support the use of magnet therapy, diuretics (unless diffuse limb edema is present), laser therapy, vitamin B6 or botulinum toxin B in the treatment of carpal tunnel syndrome. 12,15,18 Surgical Treatment Options Surgical decompression of the carpal tunnel and median nerve is one of the most common operative procedures performed in the United States, and the most frequent hand surgery. The procedure was first reported by Learmouth in 1933, but may have been performed almost 10 years earlier at the Mayo Clinic. Phalen, however, brought carpal tunnel syndrome and surgical release into the mainstream of medical knowledge in the 1950s. 24 In a systematic review of outcomes of surgical versus nonsurgical treatment for CTS, it was concluded that surgical treatment seems to be better than non-surgical 107:2 Missouri Medicine March/April

4 Figures 3 and 4 A newer procedure, the endoscopic carpal tunnel release divides the transverse carpal ligament, but leaves the overlying structures intact. low complication rates as the open procedure There is evidence that endoscopic carpal tunnel release patients may have less incisional discomfort and improved grip strength as compared to patients undergoing the open technique. 30 The ECTR procedure enables people to return to their work or daily activities approximately a week earlier. 28 treatment for relieving symptoms of carpal tunnel syndrome. 25 In particular, surgical decompression is more successful than non-surgical treatment in patients with constant numbness, neurological deficits, or long duration of symptoms. 2 In patients with severe CTS, who are unresponsive to conservative measures, it may be the only alternative that will provide a definitive treatment. Surgery consists of dividing the transverse carpal ligament, thereby increasing the tunnel volume and reducing the pressure on the nerve. The traditional open carpal tunnel release (OCTR) procedure consists of a long, palmar curvilinear incision to divide the transverse carpal ligament. (See Figures 1 and 2) In addition to the transverse carpal ligament, the overlying structures from the skin to the median nerve are divided. 26 A newer procedure, the endoscopic carpal tunnel release (ECTR), divides the transverse carpal ligament, but leaves the overlying structures intact. (See Figures 3 and 4) The ECTR procedure provides similar degrees of symptom relief and Case Report SD is a 66-year-old female who presented to the neurosurgical clinic with complaints of neck pain and numbness in her right hand for over three months. Her medical history included Type II diabetes, mild obesity, hyperlipidemia, and arthritis. She had a surgical history of bilateral knee replacements the previous year. She had worked as a hairdresser, but had been unable to work for several months because of difficulty with right hand dexterity. She had been evaluated by her family physician who ordered cervical X-rays and EMG/NCV studies of her upper extremities. The neurophysiologic studies demonstrated early axonal injury of the right median nerve, consistent with moderate to severe right carpal tunnel syndrome. There was no evidence of cervical radiculopathy. The X-rays revealed degenerative changes in the cervical spine. During her initial visit, the patient reported constant numbness in her right hand, as well as wrist and hand pain that ascended into her forearm. Tinel s sign and Phalen s test were positive. Because of her neck pain, and degenerative changes in the cervical spine, an MRI of her cervical spine was ordered. The MRI revealed moderate spondylosis and stenosis at C5-6 and C6-7. Since her prevailing complaints were hand symptoms, both non-surgical and surgical treatment 122 March/April :2 Missouri Medicine

5 options for CTS were discussed with the patient. Since her hand symptoms had prevented her from working and the EMG/NCV showed early axonal injury, surgery for carpal tunnel release was offered. The options of an open carpal tunnel release and an endoscopic carpal tunnel release were discussed with the patient and she elected to proceed with an ECTR. After the procedure, she noted almost immediate improvement of her paresthesias, except for some mild residual numbness in the thumb. Occupational therapy (OT) was ordered for her hand, and after several weeks of occupational therapy, she successfully returned to full-time work as a hairdresser. During the postoperative period, she was also sent to physical therapy for her neck complaints and her cervical symptoms improved significantly. The patient was very pleased with her surgical outcome and her ability to return to gainful employment at her previous occupation. Discussion Carpal tunnel syndrome is a common problem encountered in primary care as well as specialty care practice. In mild to moderate CTS, a common sense, evidence-based approach should include conservative medical management prior to considering surgical decompression. Wrists splints, oral corticosteroids, judicious steroid injections, ultrasound and physiotherapy are all potentially beneficial non-surgical treatment options. In patients with severe CTS, or those who have failed to improve with an adequate trial of medical management, surgical decompression is recommended. Although the open carpal tunnel release and the endoscopic carpal tunnel release have equally high clinical improvement rates, the endoscopic technique may allow the patient to return to normal activities and work in a more timely fashion. The senior neurosurgeon (SRG) of this neurosurgical practice has performed nearly 1000 endoscopic carpal tunnel releases over the last 15 years with excellent results. In his experience, there have been no nerve, tendon or vascular injuries and no postoperative infections. Early in this experience, two patients had persistent symptoms and suboptimal relief of symptoms with the endoscopic procedure. They subsequently underwent open release without significant improvement of their symptoms. References 1. Mondelli M, Giannini F, Giacchi M. Carpal tunnel syndrome incidence in a general population. Neurology 2002;58: Katz JN, Keller RB, Simmons BP, et al. Maine carpal tunnel study: outcomes of operative and nonoperative therapy for carpal tunnel syndrome in a community-based cohort. J Hand Surg 1998;23A: Viera AJ. Management of carpal tunnel syndrome. Am Fam Physician 2003;68: Jarvik JG, Yuen E, Haynor DR, et al. MR nerve imaging in a prospective cohort of patients with suspected carpal tunnel syndrome. Neurology 2002;58: Wilson JK, Sevier TL. A review of treatment for carpal tunnel syndrome. Disability and Rehabilitation 2003;25: Bland JDP. Carpal tunnel syndrome. BMJ 2007;335: MacFarlane GJ. Identification and prevention of work-related carpal-tunnel syndrome. The Lancet 2001;357: Andersen JH. Computer use and carpal tunnel syndrome. JAMA 2003;289: Ropper AH, Brown RH. Adams and Victor s principles of neurology, 8th Ed. New York, NY: McGraw-Hill Atroshi I, Gummesson C, Johnsson R, Ornstein E. Diagnostic properties of nerve conduction tests in population-based carpal tunnel syndrome. BMC Musculoskeletal Disorders 2003;4: Flak M, Durmala J, Czernicki K, Dobosiewicz K. Double crush syndrome evaluation in the median nerve in clinical, radiological and electrophysiological examination. Stud Health Technol Inform 2006;123: Sevim S, Dogu O, Camdeviren H, et al. Longterm effectiveness of steroid injections and splinting in mild and moderate carpal tunnel syndrome. Neurol Sci 2004;25: Piehl JH. Which nonsurgical treatments for carpal tunnel syndrome are beneficial? Am Fam Physician 2003;68: O Connor D, Marshal S, Massy-Westropp N. Non-surgical treatment (other than steroid injection) for carpal tunnel syndrome. Cochrane Database Syst Rev. 2003:CD Piazzini DB, Aprile I, Ferrara PE, Bertolini C, Tonali P, Maggi L, Rabini A, Piantelli S, Padua L. A systematic review of conservative treatment of carpal tunnel syndrome. Clinical Rehabilitation 2007;21: Hui ACF, Wong SM, Wong KS, et al. Oral steroid in the treatment of carpal tunnel syndrome. Ann Rheum Dis 2001;60: Chang MH, Ger LP, Hsieh PF, Huang SY. Two weeks of prednisolone was as effective as four weeks in improving carpal tunnel syndrome symptoms. J Neurol Neursurg Psychiatry 2002;73: Aufiero E, Stitik TP, Foye PM, Chen B. Pyridoxine hydrochloride treatment of carpal tunnel syndrome: a review. Nutrition Reviews 2004;62: Marshall S, Tardif G, Ashworth N. Local corticosteroid injection for carpal tunnel syndrome. Cochrane Database Sys Rev 2003:CD O Gradeigh D, Merry P. Corticosteroid injection for the treatment of carpal tunnel syndrome. Ann Rheum Dis 2000;59: Ly-Pen D, Andreu JL, de Blas G, Sanchez-Olaso A, Millan I. Steroid injection equivalent to surgery for carpal tunnel syndrome. Arthritis Rheum 2005;52: McKeon JMM, Yancosek KE. Neural gliding techniques for the treatment of carpal tunnel syndrome: a systematic review. Journal of Sport Rehabilitation 2008;17: O Connor D, Marshall SC, Massy-Westropp N. Non-surgical treatment (other than steroid injection) for carpal tunnel syndrome. Cochrane Database of systematic Reviews 2003, CD Wardle NS, Pourgiezis N, Ashwood N, Gain GI. A history of carpal tunnel syndrome. British Journal of Hospital Medicine 2008;69: Verdugo RJ, Salinas RA, Castillo JL, Cea JG. Surgical versus non-surgical treatment for carpal tunnel syndrome. Cochrane Database Sys Rev 2008, Issue 4: CD Gerritsen AAM, Uitdehaag BMJ, van Geldere D, Scholten RJPM, de Vet HCW, Bouter LM. Systematic review of randomized clinical trials of surgical treatment for carpal tunnel syndrome. British Journal of Surgery 2001;88: McNally SA, Hales PF. Results of 1245 endoscopic carpal tunnel decompressions. Hand Surgery 2003;8: Scholten RJPM, Mink van der Molen A, Uitdehaag BMJ, Bouter LM, de Vet HCW. Surgical treatment options for carpal tunnel syndrome. Cochrane Database Sys Rev 2007, Issue 4:CD Ferdinand RD, MacLean JGB. Endoscopic versus open carpal tunnel release in bilateral carpal tunnel syndrome. J Bone Joint Surg (Br) 2002;84B: Pajardi G, Pegoli L, Pivato G, Zerbinati P. Endoscopic carpal tunnel release: our experience with 12,702 cases. Hand Surgery 2008;13(1): Disclosure None reported. MM 107:2 Missouri Medicine March/April