Utilization of nerve conduction studies in the investigation and management of carpal tunnel syndrome varies according to their perceived usefulness and availability. The use of steroid injections and splinting also varies according to service availability and their perceived effectiveness. We present a three year follow up of 230 patients managed in an environment where nerve conduction testing was not readily available. The majority received splinting and a steroid injection in an effort to manage their symptoms conservatively in the first instance. Our results show that a clear majority of patients who were treated with initial splinting and steroid injections saw a recurrence of their symptoms (71.9% and 79.7% respectively) requiring eventual surgical decompression. These results would seem to suggest that conservative management of carpal tunnel does not produce the desired curative results and that there may be an argument for proceeding directly to surgery. We also showed that 55% of patients referred for Nerve Conduction Studies seem to progress to surgical decompression. This would seem to suggest that Nerve Conduction Studies could form a robust part of the standard investigation of carpal tunnel in order to identify those who would benefit from surgery

Aims. The sensitivity and specificity of electrodiagnostic parameters in diagnosing carpal tunnel syndrome (CTS) have been reported differently, and this study aims to address this gap. Methods. This case-control study was conducted on 57 cases with CTS and 58 controls without complaints, such as pain or paresthesia on the median nerve. The main assessed electrodiagnostic parameters were terminal latency index (TLI), residual latency (RL), median ulnar F-wave latency difference (FdifMU), and median sensory latency-ulnar motor latency difference (MSUMLD). Results. The mean age in cases and controls were 50.7 years (SD 9.9) and 47.9 years (SD 12.1), respectively. The CTS severity was mild in 20 patients (34.4%), moderate in 19 patients (32.8%), and severe in 19 patients (32.8%). The sensitivity and specificity of the electrodiagnostic parameters in diagnosing CTS were as follows: TLI 75.4% and 87.8%; RL 85.9% and 82.5%; FdifMU 87.9% and 82.9%; and MSUMLD 94.8% and 60.0%, respectively. Conclusion. Our findings indicated that electrodiagnostic parameters are significantly associated with the clinical manifestation of CTS, and are associated with high diagnostic accuracy in CTS diagnosis. However, further studies are required to highlight the role of electrodiagnostic parameters and their combination in CTS detection. Cite this article: Bone Jt Open 2024;5(10):898–903

To compare the efficacy of local steroid injection with surgical decompression in treatment of carpal tunnel syndrome (CTS) in terms of frequency of pain. This randomized controlled study was conducted at the Department of Orthopaedics for a duration of 01 year, i.e. from 20th April 2016 to 19th April 2017. 130 patients with carpal tunnel syndrome with moderate (Grade 2) and severe (Grade 3) pain were included. Lottery method was used to allocate the patients randomly into two groups. Group A contained 65 patients who were subjected to surgical decompression and 65 patients were in Group B who were injected with local steroid injection. Complete history was obtained from all patients. All the surgical decompressions through mini incision technique and injections procedures were performed. Information were recorded in a pre designed Performa. Efficacy was observed significantly high in group B as compared to group A (87.7% vs. 72.3%, p=0.028). Carpal Tunnel syndrome symptoms were alleviated with surgical decompression as well as local steroid injection at a follow up done after 1 month. However the steroid injections seem to have greater efficacy than surgical decompression, hence we suggest it for routine treatment of all patients with CTS. For any reader queries, please contact . virgo_r24@hotmail.com

In a prospective study, we have evaluated the impact of psychological disturbance on symptoms, self-reported disability and the surgical outcome in a series of 110 patients with carpal tunnel syndrome. Self-reported severity of symptoms and disability were assessed using the patient evaluation measure and the Boston carpal tunnel questionnaire. Psychological distress was assessed using the hospital anxiety and depression scale. There was a significant association between psychological disturbance and the pre-operative symptoms and disability. However, there was no significant association between pre-operative psychological disturbance and the outcome of surgery at six months. We concluded that patients with carpal tunnel syndrome should not be denied surgery because of pre-operative psychological disturbance since it does not adversely affect the surgical outcome

We aimed to prospectively assess the familial incidence of Carpal tunnel syndrome (CTS). 151 patients undergoing elective carpal tunnel surgery at a district general hospital were given a written questionnaire on the day of surgery. Patients were asked to give details of all adult family members and to identify relatives that had been diagnosed with CTS by a doctor or had undergone CTS surgery. CTS is commonly associated with pregnancy, trauma, hypothyroidism, diabetes, gout and rheumatoid arthritis. We asked if the patients had any of these conditions. All patients were contacted by telephone within one month of surgery to validate the data collected. The average age was 58. 4 (Range 28 – 84). The female / male ratio of patients undergoing surgery was 4A. Overall 26% of patients had a relative with CTS. 7. 8% of children (aged > 20), 2. 4% of parents and 4. 2% of siblings were affected. A study of 44, 233 US workers reported a prevalence of 1. 55%. The child of a person with CTS is therefore 5 times more at risk of developing CTS than the normal population. Many parents were deceased resulting in a lower recorded prevalence for this group. Familial CTS was more common than any of the conditions traditionally associated with CTS (Except pregnancy). Familial Carpal Tunnel Syndrome is common. Family history should be enquired about in occupations at risk of developing carpal tunnel syndrome

Introduction: Carpal tunnel syndrome is frequent in children with mucopolysaccharidosis. Diagnosis is difficult according to the slow progression of compression of the medial nerve and treatment is controversial. Material & Methods: Twelve children were studied: 8 Hurler’s, 2 Hunter’s and 2 Maroteaux-Lamy’s diseases. All had clinical and EMG evaluation. Eight of them were operated, both sides. Results: All the children had progressive and severe hypoesthesia before surgery. Nerve conduction velocity was very slow compared to normal values. After the open surgical release (16 cases) and synovectomy of flexor tendons (13 of 16 cases), all the patients were improved. The histology of the synovitis showed less glycosaminoglycans in patients who had a bone marrow transplantation. Surgical treatment must be an open release of the anterior ligament associated with a synovectomy of flexor tendons and a ventral epineurotomy. Discussion: According to the literature, carpal tunnel syndrome is observed in two third of patients of type I, II and VI mucopolysaccharidosis. Diagnosis is often difficult when cervical compression of the spinal cord is an associated factor. The diagnosis is made with clinical and EMG evaluation. Treatment must be early. MRI is an alternative to evaluate the morphology of the nerve: its compression below the carpal ligament and its bulky aspect just proximal to the carpal tunnel are clearly shown

Background. To investigate the new theory of hydroneurolysis and hydrodissection in the treatment of carpal tunnel syndrome (CTS). Independently of the fluid hydrodissolution works due to mechanical forces and it may have some positive effects in patients with ischemic damage caused by scar tissue pressure at the nerve's surface. Methods. A prospective blind clinical study of 31 patients suffering from carpal tunnel syndrome, established by nerve conduction studies and clinical tests. 14 patients (out of 29), who refused to undergo an open operation as a treatment to their disease at this point of time, were treated with a simple ultrasound-guided injection at the proximal carpal tunnel. In order to exclude the biochemical influence of the fluid in the treating disease we choosed to infiltrate 3 cc. of normal saline 0,9%. In the follow-up period our group was asked to answer to a new Q-DASH score and visual analogue scale (VAS) 100/100 in 2, 4 and 8 weeks. Results. At the end of the second month we found only 2 out of 14 patients of the infiltration's group with clinical improvement. As far as the control group (17 patients), there was just one patient with recovery of the symptoms at the end of the second month who avoided operation. The rest 16 patients experienced insistence or worsening of CTS while they were waiting to be operated (mean time till operation in our department's waiting list: 2 months) and underwent a surgical decompression of the median nerve. Comparing the two groups in Q-DASH score, VAS 100/100 and ultrasound cross sectional area measurements we found no statistical difference between the two groups at the endpoint of our follow-up period. Conclusion. As far as nerve entrapment syndromes we proved that normal saline hydrodissolution appears to be non effective as a conservative treatment. The mechanical way of action seems to have only very short term effects. Level of Evidence. II

Carpal tunnel syndrome is a common condition with a prevalence of 2.7% based on symptoms, clinical signs, and neurophysiology. The procedure to cure these patients, whether it is open or endoscopic, is usually successful in returning sensation, abolishing numbness and paraesthesiae, and improving manual dexterity. However, as many as 14%–32% of patients may have persistent symptoms. The general treatment of patients with recurrent carpal tunnel syndrome is re-exploration of the median nerve and neurolysis. Various procedures have been described to cover the median nerve with muscle or fat tissue. These include–external neurolysis, local muscle flaps, fat grafts and flaps, vein wrapping and synovial flaps. The outcome of secondary carpal tunnel surgery is only fair and many procedures are possible. In 19 patients presenting with recurrent carpal tunnel syndrome over a period of five years, silicone sheath was used to cover the median nerve following neurolysis. All of these 19 cases were performed by the senior author (ASR). We audited the results of this procedure using the carpal tunnel outcome instrument (Levine et al., 1993) for subjective assessment and grip strength, thumb key pinch force and two point discrimination sensation for Objective assessment. 17 patients were followed up for the purpose of this study. 2 were lost to follow up. Twelve patients were satisfied with their outcomes and were prepared to undergo the surgery again or recommend it to others (more than 70%). However, two were dissatisfied and three were uncertain of their feelings

Carpal tunnel syndrome (CTS) is the most common condition affecting the hand, with a prevalence of 2–3% in most populations, and a lifetime incidence over 10%. There is consensus that CTS results from increased pressure in the carpal tunnel, which eventually affects nerve function, but, aside from direct trauma and space occupying lesions, there is no consensus on what causes the pressure to rise. In the absence of an identifiable biological mechanism, the most common treatment involves surgical opening of the carpal tunnel. Recent data suggests that CTS patients demonstrate, in the carpal tunnel synovium and subsynovial connective tissue (SSCT), evidence of cellular senescence, with a senescence associated secretory phenotype (SASP). This finding suggests the potential for a biological treatment for CTS with senolytic drugs. This presentation will review the evidence for CTS as a disease of cellular senescence, and our preliminary data on the effects of senolytics, including in a relevant animal model of CTS and SSCT fibrosis

The aim of this study was to evaluate the morbidity associated with carpal tunnel syndrome and the outcome following surgical treatment using the Nottingham Health Profile (NHP). Between 1994 and 1996 we performed a prospective study of the effect of carpal tunnel release on the health status of 96 patients. The Nottingham Health Profile, a validated generic scoring system was used to assess quality of life, before and after surgery. 96 patients with 103 symptomatic hands were studied over this two year period. The patients completed a questionnaire before and 4 months after surgery. The notes were reviewed by an independent assessor and data collected with regard to duration and nature of symptoms, associated conditions, patients’ satisfaction and complications. 72 patients were satisfied with the results of surgery and 24patients were dissatisfied despite in the main clinical improvement. There was a significant improvement in the scores for pain, physical mobility and sleep 4 months following surgery in all patients. We observed that those patients with a significantly high pre-op NHP score fared less well than cohorts, developing more frequent complications and overall were more likely to be dissatisfied with the results of surgery. This group of dissatisfied patients had previously been indistinguishable from their cohorts and were as it were invisible. The high NHP scores provided an objective way of identifying this group of individuals. Carpal tunnel syndrome had a notable impact on the health status of our patients. There was a significant improvement in the NHP scores 4 months following surgery. Our findings show that outcome assessment tools have predictive value in identifying patients who may not benefit from surgery or in whom a poor result might be anticipated

Current opinion is divided as to whether carpal tunnel syndrome requiring operative decompression can be caused by an occupation. The aims of this study were to define the lamb freezing worker population who acquire carpal tunnel syndrome and to confirm or refute lamb boning as an occupational cause for carpal tunnel syndrome. Roles, gender age and exposure periods of all workers who had carpal tunnel decompressions over the past six seasons at the largest lamb Freezing Works in the world were examined. Kaplan-Meier survival analysis for boners, slaughter men and non-knife labourers was performed and tested for significance. Chi-square analysis and ANOVA were performed for gender and age. Age and gender-adjusted Cox regression analysis was performed to establish relative risks/hazard ratios for each of the three groups developing carpal tunnel syndrome. Incidences for boners and non-knife hands were calculated. Comparison of this population and a standard carpal tunnel population was performed. Two hundred and eighty five carpal tunnel decompressions were performed in workers who failed conservative management at the largest lamb freezing works in the world by a single surgeon after neurophyiological-test confirmation of the diagnosis. Of those having surgery 79% were men: 21% female and this was significant with Chi square testing (p< 0.01). At decompression boners were significantly younger than non-knife hands (p< 0.01). Adjusting for age and gender boners were 120% more likely to need decompression than non-knife labourers (p< 0.01). The median survival for a lamb boner’s carpal tunnel at five years was 44%. The incidence of carpal tunnel syndrome in lamb boners was 10% (person-seasons). This population is entirely different to the published idiopathic population requiring carpal tunnel decompression which is predominantly female with meanage of 55. To our knowledge this is the first study to provide sound evidence that carpal tunnel syndrome can be caused by an occupation. We have quantified this and welcome ideas for further work in this fascinating a uniquely New Zealand population

Background: Median nerve motor branch compression in patients with Carpal Tunnel Syndrome is usually characterised by reduced finger grip and pinch strength, loss of thumb abduction and opposition strength and thenar atrophy. Surgical decompression is usually necessary in these patients but may result in poor outcomes due to irreversible intraneural changes. Hypothesis: The aim of this study was to investigate patient-reported symptoms which may enable a clinical diagnosis of median nerve motor branch compression to be made irrespective of the presence of advanced signs. Methods: One-hundred-and-twelve patients (166 hands) with a clinical diagnosis of Carpal Tunnel Syndrome were referred to the neurophysiology department and completed symptom severity questionnaires with subsequent neurophysiological testing. Results: An increasing frequency of pain experienced by patients was significantly associated with an increased severity of median nerve motor branch compression with prolonged motor latencies measured in patients that described pain as a predominant symptom. An increasing frequency of paraesthesia and numbness and weakness associated with dropping objects was significantly associated with both motor and sensory involvement but not able to distinguish between them. Conclusion: This study suggests that patients presenting with a clinical diagnosis of carpal tunnel syndrome with pain as a frequently experienced and predominant symptom require consideration for urgent investigation and surgical treatment to prevent chronic motor branch compression with permanent functional deficits. Level of evidence: Prognostic study level 2

Objective: This article describes the outcome of a nurseled service developed to manage patients referred with a presumptive diagnosis of carpal tunnel syndrome. We also describe the implementation of a nurse-led preoperative assessment and postoperative care clinic. Design: We assess the safety, efficacy and outcomes of 402 patients referred to the Department of Orthopaedic, University Hospital Lewisham for carpal tunnel decompression surgery prospectively. Patients and Methods: The service was developed around the role of a nurse practitioner providing a single practitioner pathway from first clinic appointment to discharge. General practitioners were advised of the service and the criteria for referral, which included patients with symptoms and physical signs, and some response to conservative treatment. Patients were assessed in the nurse-led preoperative assessment clinic and those deemed suitable for surgery were listed for operation. Results: 12.7 % patients (51 patients) were referred for electromyographic studies and 5.2% patients (21 patients) were referred to doctors for further consultations. Only 4 patients had trigger finger and a further 4 patients had De Quervians syndrome. Of the remaining 373 patients, 7 patients (1.8%) choose to wait before considering surgery, and 2 patients (0.5%) declined surgery. Waiting times improved considerably whilst the standard and quality of care was maintained. Conclusions: We developed a rapid-access service in response to unacceptable waiting times for patients with carpal tunnel syndrome. Implementing such a clinic improved access to care for patients with this particular problem. The safety and efficacy of the program and patient-centred outcomes commend its adaptation and implementation to other institutions. As the clinical diagnosis of Carpal tunnel syndrome is often easily made, a system of direct referral for carpal tunnel surgery was introduced. The service was an alternative to standard consultants’ outpatient referral. Direct access to a nurse-led carpal tunnel syndrome assessment clinic works well and it will reduce delays and the costs of treatment. Adequate patient information is vital to make the best of the service. There is a role for nurses to perform certain clinic within a well-defined environment

Background & Objectives. Sensory and motor manifestations in carpal tunnel syndrome (CTS) are well documented, whereas the associated autonomic dysfunction is often overlooked. The aim of this study is to demonstrate that autonomic dysfunction of the CTS hands can be quantified by measuring skin capacitance. Methods. Patients with clinical and electrophysiological signs of idiopathic carpal tunnel syndrome meeting the inclusion criteria were recruited. The patients were also scored based on the Brigham carpal tunnel severity score. Skin capacitance was measured using Corneometer CM825 (C&K Electronic, GmbH). The measurements were taken from the palmar aspect of distal phalanx of the index and little finger of the affected hand. Normal healthy patients with no signs and symptoms of carpal tunnel syndrome were recruited as controls and skin capacitance was measured in a similar fashion as the CTS group. Results. The CTS group consisted of 25 patients (18 female & 7 male) and 35 hands with an average age of 59.2 years (33-83 years). The mean symptom severity score was 2.80 (1.27-4.18; SD 0.82) and functional status score was 2.53 (1-4.26; SD 1.08). The mean ratio of skin hydration between the index and little finger was 0.85 (0.6-1.25; SD 0.155). Using the paired t-test to determine paired differences between index and little finger measurements, the mean difference was 12.6 (p<0.001). The control group consisted of 15 people (9 female and 6 male) and 30 hands. The average age was 47.3 years. The mean ratio of skin hydration between the index and little finger was 0.97 (0.77-1.42 SD 0.105). Using the paired t-test to determine paired differences between index and little finger measurements, the mean difference was 1.31 (p=0.317). The difference in skin hydration between the index and little finger was directly compared between the controls and CTS group, this difference was statistically significant, p=0.002. Conclusion. A simple method to determine dysautonomia, using Corneometer CM825, by the clinician has been demonstrated. Measurement of skin capacitance will reduce the dependence on electrophysiological studies, thus reducing the time for arriving at a diagnosis, improved patient satisfaction and cost-effectiveness

Carpal tunnel syndrome is the most common compressive neuropathy of the upper limb. Various methods are used to diagnose this condition including clinical examination and neurophysiologic tests. The DASH (Disability of Arm, Shoulder and Hand) score is also commonly used to quantify the symptoms from the patients’ perspective. The aim of this study was to determine any correlation between the neurophysiology and the various questions in the DASH score. To the best of our knowledge this potential association has not been studied previously. Methods: We reviewed 55 patients who underwent carpal tunnel surgery under the care of the senior author. Case notes were reviewed to extract the DASH score, clinical signs and neurophysiology results. DASH questionnaires are routinely given to all our new patients in the hand clinic and we used these questionnaires for the study (pre operative scores). All the patients were examined clinically by the senior author. The clinical signs used included direct compression, Tinel’s and Phalen’s test. Neurophysiologic testing was conducted by two specialists using a standard format which allowed us to extract the data consistently. Analysis: The data was analysed using linear and logistical regression methods. Results: Of 55 patients, 9 had bilateral surgery, resulting in 64 sets of data. There were 44 females and 11 males, with a mean age of 62 (range 36 – 86) years. The mean DASH score was 38.0 (range 0.8 – 85.0). The relationship between the component scores of the DASH questionnaire and neurophysiology tests will be presented in further detail. Conclusion: The results of this study may facilitate an abbreviation of the DASH questionnaire, making it more focused to patients with carpal tunnel syndrome

Aims. The aim of this study was to compare the efficacy of a corticosteroid injection for the treatment of carpal tunnel syndrome (CTS) in patients with and without Raynaud’s phenomenon. Patients and Methods. In a prospective study, 139 patients with CTS were treated with a corticosteroid injection (10 mg triamcinolone acetonide); 34 had Raynaud’s phenomenon and 105 did not (control group). Grip strength, perception of touch with a Semmes-Weinstein monofilament and the Boston Carpal Tunnel Questionnaires (BCTQ) were assessed at baseline and at six, 12 and 24 weeks after the injection. The Cold Intolerance Severity Score (CISS) questionnaire was also assessed at baseline and 24 weeks after the injection

Introduction: Carpal tunnel syndrome is the most commonly occurring peripheral nerve entrapment syndrome and perhaps also the commonest peripheral nerve to be released. Increasingly there is a suggestion that carpal tunnel syndrome (CTS) is a bilateral disease with the reported incidence of between 16% and 87% and hence the enthusiasts favour bilateral simultaneous carpal tunnel decompression (CTD). Our hypothesis is that there is an increased likelihood of over-treating these patients with this approach of simultaneous carpal tunnel decompression. Materials and Methods: A retrospective study was conducted to review records of 245 patients who underwent CTD at the Regional Hand Surgery Unit between April 2005 and August 2007. Patients who were referred with symptoms of bilateral CTS and underwent open CTD on at least one wrist were included in the study. The two groups hence formed were Group A comprising patients who underwent consecutive CTD where as Group B comprised patients who underwent only unilateral CTD before discharge. All patients booked for surgery were provided with a resting splint preoperatively. They were reviewed on one or more occasion before listing for decompression on the other side or discharged. Results: A total of 131 met the inclusion criterion. Group A includes 76 (58%) patients and had symptoms on both sides and signs in 64 (84%) patients. Nerve conduction tests confirmed median nerve compression in 59/60 (98%) patients. Group B includes 55 (42%) patients and had symptoms suggestive of CTS on both sides and signs in 45 (82%) patients. Nerve conduction studies confirmed nerve compression in 38/41 (93%) patients. All patients were followed up for minimum of 6 months before being discharged from further review. At the end of the study, 48/131 (37 %) patients were successfully discharged after a minimum of six months follow up without an operation on the contralateral side. Discussion: Our study has confirmed the bilateral nature of the disease. Current literature supports simultaneous CTD as it has been shown to be economic to the patient, employers and the healthcare industry. Studies have shown that symptoms are usually severe on one side and sometimes treatment of one hand may lead to the improvement, exacerbation or absence of effect in the other hand regardless of electromyographic findings. 45/131 (37 %) patients in our study were successfully discharged without an operation on the contralateral side after a minimum of six months follow up. Hence, this supports our hypothesis that by following an approach of simultaneous bilateral CTD, there is a increased likelihood of over-treating these patients and exposing them to the potential complications

Eight cases of carpal tunnel syndrome are reported, all of which developed in patients on haemodialysis for chronic renal failure. In each case the arm involved had been used for a fistula. The aetiology of the syndrome in these patients is discussed; it is multifactorial, but related to the sites of arteriovenous fistulae. Decompressing the carpal tunnel provides effective and lasting relief

Carpal tunnel syndrome is the most frequent form of median nerve entrapment, accounting for 90% of all entrapment neuropathies. Routinely nerve conduction study (NCS) tests are ordered to confirm the diagnosis however; there are issues of long waiting periods and costs with it. We aimed to compare carpal tunnel questionnaire score (CTQS) by Kamath and Stothard (2003) to nerve conduction study result in the diagnosis of carpal tunnel syndrome. This prospective study involved analysis of data from all the patients referred to NHS Tayside (Dundee) hand clinic with signs and symptoms of Carpal tunnel syndrome (CTS) from September 2016 to February 2017. Statistical analysis was done using SPSS and sensitivity and specificity was calculated. The questionnaires were filled in by a team of specialist physiotherapists. Nerve conduction study tests were done by a team of consultant neurophysiologists. Both the groups were blinded to each other's assessment. We analysed 88 patients who filled in CTQS and also underwent NCS. We noted that CTQS of less than 3 correlated 100% to negative nerve conduction result. When the carpal tunnel questionnaire score was more than or equal to 5, 54 patients had positive NCS result and 6 patients had negative NCS result, giving a 90% predictability of a positive NCS result. Mean waiting period of carpal tunnel patients for NCS was 141 days. We noted from this prospective study that CTQS was sensitive enough to exclude carpal tunnel syndrome when the questionnaire score was less than 3. In addition, the questionnaire revealed a 90% probability of having carpal tunnel syndrome when CTQS was more than or equal to 5. Based on the present study, we would recommend that patients in grey zone of 3 to 4 on questionnaire should undergo NCS, resulting in only 20% of patients (based on the figures from the current study) being referred for NCS. The questionnaire can be used in primary health care or specialist physiotherapy screening clinic as a tool for diagnosing CTS with implications of cost saving and avoiding long waiting periods

Introduction. Carpal tunnel syndrome is a common neuropathy of the median nerve. Occupation has been widely examined as a risk factor for the development of carpal tunnel syndrome. The aim of this study was to examine the validity of the United Kingdom (UK) NS-SEC (National Statistics Socioeconomic Classification) in the assessment of correlation between occupation and CTS. Methods. A prospective audit database was collected of patients diagnosed with CTS over a 6 year period. Occupation was assessed using the NS-SEC self coded method, where occupation is classified depending on the type of job and the size of the employer. UK Census data from 2001 was used to compare the occupation profile of the cohort with the regional population. Results. There were 1564 patients diagnosed with CTS over a 6 year period. There were fewer patients with CTS in managerial and professional occupations (OR 0.77 95% CI 0.66 to 0.9), lower supervisory and technical occupations (OR 0.33, 0.23 to 0.45), and semi-routine and routine occupations (OR 0.68, 95% CI 0.58 to 0.79). There was a higher proportion of patients who were self-employed (OR 4.60, 3.93 to 5.30). Discussion. The NS-SeC is superficially attractive to assess occupational differences between a general population and a study group due to the availability of census data. This study has shown a higher proportion of patients having CTS in the self-employed category than in the general population. Such occupational classifications that are based on economic inidicators may not be useful in assessing exposure to risk factors for musculoskeletal disorders. Caution should be exercised in their use and more accurate scores developed that address physical intensity of an occupation