Carpal tunnel syndrome

PURPOSE OF REVIEW: Carpal tunnel syndrome, though generally successfully treated by surgical decompression, still results in significant morbidity. The causes remain unclear and there is uncertainty about appropriate investigations for diagnosis and assessment of severity. The best nonsurgical treatment is yet to be fully elucidated. Recent work has begun to cast some light on these uncertainties. RECENT FINDINGS: The pathology of idiopathic carpal tunnel syndrome is a noninflammatory fibrosis of the subsynovial connective tissue surrounding the flexor tendons. Biochemical studies of surgical specimens suggest that a variety of regulatory molecules may be inducing fibrous and vascular proliferation and that this may be a response to mechanical stresses. Ultrasound imaging has begun to demonstrate its ability to accurately image the carpal canal contents and the diagnostic value of measurements of median nerve cross-sectional area showing expansion of the nerve is becoming established. The sensitivity and specificity of such measurements may be comparable to those of nerve conduction studies, though their prognostic value remains unknown. Nonsurgical treatment with steroid injection may be a more effective treatment than previously recognized, and is under used. SUMMARY: Suspected carpal tunnel syndrome should be investigated first with nerve conduction studies but consideration should be given to the use of magnetic resonance imaging or ultrasound imaging when diagnostic uncertainty remains, or there is a suspicion of a space occupying lesion in the carpal canal, especially if endoscopic surgery is contemplated. Treatment by local steroid injection should be considered a valid alternative treatment, at least for milder cases.     

Prevalence of Epilepsy in Rochester, Minnesota: 1940–1980

The prevalence of epilepsy in Rochester, Minnesota has been determined for a specific date in each of 5 decennial census years. Individuals with a diagnosis of epilepsy (recurrent unprovoked seizures) who were known to have experienced a seizure or who had received antiepileptic medication in the preceding 5 years were considered active prevalence cases. By this definition, the age-adjusted prevalence per 1,000 population, increased steadily from 2.7 in 1940 to 6.8 in 1980. At each of five prevalence dates, for all prevalence cases, 60% had epilepsy manifest by partial seizures, and 75% had no known etiology. Prevalence was higher for males than females for all except the last prevalence day. After 1950, prevalence tended to increase with advancing age and was highest in the oldest age groups. On the average, the 1980 prevalence cases had epilepsy less than 10 years and greater than 50% had their first diagnosis in the first 20 years of life.     

Incidence of epileptic syndromes in Rochester, Minnesota: 1980-1984

PURPOSE: To determine the incidence and the distribution of epileptic syndromes in a well-defined population. METHODS: By using the records-linkage system of the Rochester Epidemiology Project, we screened all the residents of Rochester, Minnesota, who received a diagnosis of seizures, convulsions, or epilepsy from 1980 through 1984. One hundred fifty-seven residents with incident epilepsy (recurrent unprovoked seizures) were classified by using the International League Against Epilepsy (ILAE) Classification of the Epilepsies and Epileptic Syndromes. Residents with special syndromes were excluded. With a pretested algorithm, patients were classified at three levels of specification: major syndromic groups (e.g., localization-related syndromes), syndromic subgroups (e.g., idiopathic epilepsy with age-related onset), and whenever possible, individual syndromes. RESULTS: All but one patient were classified into major syndromic groups and subgroups. The annual age-adjusted incidence per 100,000 population was 52.3 cases (34.9 for localization-related epilepsies; 7.7 for generalized epilepsies; 9.7 for undetermined epilepsies). Incidence was 0.2 for idiopathic, 17.2 for cryptogenic, 17.5 for symptomatic localization-related epilepsies, 3.7 for idiopathic, 1.7 for symptomatic or cryptogenic (age-related), and 2.3 for symptomatic (non age-related) generalized epilepsies. CONCLUSIONS: With the exception of idiopathic epilepsies, the incidence of the major syndromic categories in our study was higher than that provided by previous population-based studies.     

Carpal tunnel syndrome & cubital tunnel syndrome]

Carpal tunnel syndrome (CTS) and cubital tunnel syndrome (Cub.TS) are the two most common entrapment syndromes. Development of several validated outcome assessments have allowed conducting large scale epidemiological studies worldwide for the last decade regarding CTS, which have been providing reliable basic information. These studies have shown that CTS is more common than had been expected. It is estimated that lifetime risk of acquiring CTS is 10%, the annual incidence is 0.1% among adults, and overall prevalence is 2.7% among the general population. The most common cause is idiopathic inflammation of the flexor tendon sheath induced by activities involving repetitive wrist movement. In contrast, they are not available for Cub.TS and most data are derived from case series or expert opinion, therefore, information concerning Cub.TS is less reliable. In this lecture, the author is trying to offer up-date information of these entrapment neuropathies regarding their pathophysiology, epidemiology, and tips & pitfalls of diagnosis and treatment.     

Carpal tunnel syndrome and metabolic syndrome

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Many factors such as diabetes mellitus, hypothyroidism, hormonal replacement therapy, corticosteroid use, rheumatoid arthritis and wrist fractures may cause CTS. Metabolic syndrome includes abdominal obesity, dyslipidemia, hyperglycemia, and hypertension that may cause CTS. In this study, we aimed to evaluate the relation between CTS and metabolic syndrome. We studied 107 (96 female and 11 male) right-handed patients who had a clinical and electrophysiologically confirmed diagnosis of CTS. We then divided the patients into two groups (patients with and without metabolic syndrome) according to the criteria of ATP III definition. Eighty (75%) of the patients with CTS had metabolic syndrome. Among the 80 patients with metabolic syndrome, CTS was found in 150 hands (43 mild, 58 moderate and 49 severe cases). Among the 27 patients without metabolic syndrome, CTS was found in 43 hands (27 mild, 14 moderate and 2 severe cases). The electrophysiological parameters (median nerve distal motor latency, median nerve motor amplitude, median nerve motor conduction velocity, median nerve sensory onset latency, median nerve sensory amplitude and median nerve sensory conduction velocity) were worse in patients with metabolic syndrome (P < 0.05). In conclusion, metabolic syndrome was found to be three times more common in patients with CTS and CTS was more severe in patients with metabolic syndrome when compared with those without metabolic syndrome.     

Carpal tunnel syndrome in older adults

The clinical and electrophysiologic characteristics of carpal tunnel syndrome (CTS) in elderly adults are not well established. We examined age differences in clinical, functional, and electrophysiologic features in elderly adults referred to a neuromuscular service for evaluation of symptoms suggestive of CTS. Of 415 consecutive subjects referred over an 18-month period, 343 met clinical criteria for CTS. There were 158 young (or=65 years). There were no age differences in the duration of CTS symptoms, hand function, or presence of autonomic symptoms. The elderly adults had a higher prevalence of thenar weakness and thenar atrophy than younger subjects. Electrophysiologic abnormalities were more common and more severe in the older subjects. Our study shows that although there are no age differences in subjective complaints of CTS, older adults had objective clinical and electrophysiologic evidence of a more severe median nerve entrapment. The findings suggest that greater attention needs to be paid to objective evidence of CTS severity rather than subjective complaints when evaluating elderly adults presenting for clinical evaluation of CTS.     

Carpal tunnel syndrome in postmenopausal women

OBJECTIVE: Hormonal changes that accompany menopause have a significant impact on the nervous and other physiological systems. Our objective was to evaluate the relationship between carpal tunnel syndrome (CTS) and the clinical features of menopause in postmenopausal women, in comparison to age-matched healthy controls. METHODS: Overall, 6230 women were seen during the study period. Of these, 5587 were not eligible because they were premenopausal or perimenopausal. 537 women did not meet the criteria used in the study for a diagnosis of idiopathic CTS and were excluded. Finally, one hundred and six patients with CTS and 115 controls were examined. The presence of CTS was confirmed both clinically and electrophysiologically. Socio-demographic variables and reproductive histories were evaluated via a structured interview. RESULTS: In comparison to healthy controls, patients with CTS showed a significantly greater number of pregnancies and an earlier age at menopause. Regarding the type of menopause, patients and controls showed similar frequencies for natural versus surgical menopause. The frequency of natural menopause was significantly higher than that of surgical menopause in both groups. CONCLUSION: Our results suggest that age at menopause may be a significant factor in the development of CTS. Pregnancy-related hormonal changes may have long-term effects that increase the incidence of CTS in postmenopausal women.     

Carpal tunnel syndrome in paraplegic patients

Median nerve compression at the wrist (Carpal Tunnel Syndrome) is commonly associated with local trauma around the flexor retinaculum. Repeated manual activity also exacerbates the disease severity. We undertook a prospective study of the incidence of Carpal Tunnel Syndrome (CTS) in 47 paraplegic patients who have used their hands extensively for daily activity. Since surgical decompression generally provides excellent relief of symptoms, early detection of CTS will be particularly important in these patients. Of the 47 patients studied, 19 had clinical CTS (40%). A total of 91 hands (nerves) were tested with motor and sensory nerve conduction of the median and ulnar nerves. Electrophysiological evidence of CTS was noted in 57 hands (63%). The incidence of CTS appears to be related to the duration of Spinal Cord Injury. Concurrent ulnar neuropathy at the elbow was noted in 19 patients (40%). There was no predisposing factor such as diabetes mellitus in any of these patients, and the compressive neuropathy appears to be purely mechanical.     

Carpal tunnel syndrome in Lyme borreliosis

Neurophysiologic evidence of median nerve entrapment in the carpal tunnel was present in 25% of patients with late Lyme borreliosis. Sixty-eight of 76 consecutive, prospectively studied patients with late Lyme underwent neurophysiologic testing. Nineteen reported intermittent hand paresthesias; 17 had neurophysiologically confirmed carpal tunnel syndrome. This was not consistently associated with clinically apparent wrist arthritis or with neurophysiologically evident peripheral neuropathy. We conclude that a significant proportion of patients with late Lyme borreliosis develop carpal tunnel syndrome.     

Carpal tunnel syndrome and hyperthyroidism

We carried out a prospective study to determine the frequency and evolution of carpal tunnel syndrome (CTS) in patients with hyperthyroidism. An initial survey revealed CTS in 5% of these patients when hyperthyroidism was diagnosed. During the clinical and neurophysiologic follow-up for a two-year period, four more patients developed CTS; of these, two had uncontrolled hyperthyroidism, and the other two had iatrogenic hypothyroidism. The clinical and neurophysiologic evolution suggests a relationship between both diseases. The symptoms of CTS remitted if endocrinopathy is controlled. Surgery is, in general, not necessary. CTS can be considered another peripheral neurological manifestation associated with hyperthyroidism.     

Psychologic and social adjustment to epilepsy in Rochester, Minnesota

The psychologic and social aspects of epilepsy have rarely been assessed in community-based samples. We administered the Washington Psychosocial Seizure Inventory in 1985-1986 to 125 nonretarded adults, 18 to 59 years of age, who in 1980 had active epilepsy and resided in Rochester, Minnesota. Individuals having seizures or taking anticonvulsant medications within the past 12 months had somewhat poorer adjustment than those without recent seizures or medications, but even this more severely affected group appeared relatively well adjusted.     

Carpal tunnel syndrome in children with mucopolysaccaridoses

Carpal tunnel syndrome in children is uncommon. Mucopolysaccharidosis is the most common cause of carpal tunnel syndrome in this age group. With new treatment modalities available for mucopolysaccaridoses, the prognosis of the disease has greatly improved. The musculoskeletal manifestations including carpal tunnel syndrome now assume more importance. Early diagnosis and treatment of carpal tunnel syndrome in these children are important to achieve a good outcome. The authors present their experience in the management of children with mucopolysaccharidosis and carpal tunnel syndrome.     

Carpal tunnel syndrome secondary to ganglion cyst in a child

Carpal tunnel syndrome is uncommon in children and is associated with an underlying etiology in the majority of cases. The diagnosis of the condition in childhood is dependent on a high degree of clinical suspicion, careful clinical examination, and judicious use of confirmatory investigations. The authors report a novel cause of carpal tunnel syndrome in a child, and discuss the investigation and management strategies in childhood carpal tunnel syndrome.     

Carpal tunnel syndrome related to antebrachial Cimino-Brescia fistula.

Two patients are described in whom symptoms of the carpal tunnel syndrome were provoked by haemodialysis for which an antebrachial arteriovenous fistula had been established. The symptoms in one case were partially relieved by ligation of the radial artery distal to the fistula, and in both they were abolished by decompression of the median nerve by section of the flexor retinaculum at the wrist. There is evidence that the median nerve is abnormally susceptible to ischaemia in the carpal tunnel syndrome, and it is suggested that in these patients the symptoms were provoked by a vascular steal mechanism related to the fistula.