A systematic review of the clinical diagnostic tests for carpal tunnel syndrome

A Proposal for Neurography Referral in Patients with Carpal Tunnel Syndrome Based on Clinical Symptoms and Demographic Variables of 797 Patients

The clinical manifestation of median nerve entrapment at the carpal tunnel level is known as carpal tunnel syndrome (CTS). Electroneurography (ENG) is considered the gold standard in CTS evaluation. We conducted a retrospective study and analyzed some clinical and demographic variables, relating them to the degree of neuropathy using ENG, to better understand the role of ENG in this very common disease. We studied 816 patients referred to our service for neurographic evaluation. Their symptoms were classified as compatible with CTS (cCTS) (n = 646) and atypical for CTS (aCTS) (n = 170). A blind ENG was performed on 797 patients. Patient characteristics were coded as variables and analyzed to study whether they could predict neuropathy severity (sensory and motor involvement or grade ≥ 3 in our classification). We found a correlation between typical symptomatology, age over 50 years, male gender, positivity of Phalen's maneuver and Tinel's sign, and a neuropathy grade ≥ 3. We also found a correlation with CTS in the contralateral hand if the other hand showed neuropathy, despite the lack of symptoms in this hand. We propose a practical algorithm for ENG referral based on clinical symptoms, demographic factors, and neurophysiological variables.

Diagnostic criteria and outcome measures in randomized clinical trials on carpal tunnel syndrome: a systematic review

BACKGROUND

The diagnostic criteria for carpal tunnel syndrome (CTS) lack uniformity. Moreover, because CTS is a syndrome, there is no consensus as to which signs, symptoms, clinical and complementary tests are more reproducible and accurate for use in clinical research. This heterogeneity is reflected in clinical practice. Thus, establishing effective and comparable care protocols is difficult.

OBJECTIVE

To identify the diagnostic criteria and outcome measures used in randomized clinical trials (RCTs) on CTS.

DESING AND SETTING

Systematic review of randomized clinical trials carried out at the Federal University of São Paulo, São Paulo, Brazil.

METHODS

We searched the Cochrane Library, PubMed, and Embase databases for RCTs with surgical intervention for CTS published between 2006 and 2019. Two investigators independently extracted relevant data on diagnosis and outcomes used in these studies.

RESULTS

We identified 582 studies and 35 were systematically reviewed. The symptoms, paresthesia in the median nerve territory, nocturnal paresthesia, and special tests were the most widely used clinical diagnostic criteria. The most frequently assessed outcomes were symptoms of paresthesia in the median nerve territory and nocturnal paresthesia.

CONCLUSION

The diagnostic criteria and outcome measures used in RCTs about CTS are heterogeneous, rendering comparison of studies difficult. Most studies use unstructured clinical criteria associated with ENMG for diagnosis. The Boston Questionnaire is the most frequently used main instrument to measure outcomes.

REGISTRATION

PROSPERO (CRD42020150965- https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=150965).

Preoperative Evaluation of Thenar Muscles in Carpal Tunnel Syndrome by Ultrasonography

This article aims to evaluate the usefulness of ultrasonography for the measurement of thenar muscles in carpal tunnel syndrome (CTS). A total of 85 patients with CTS who had a carpal tunnel release procedure were included in this study. The transducer was applied onto the palmar surface of the hand perpendicularly to the longitudinal axis of the first metacarpal bone. Thenar atrophy was evaluated visually and classified using the visual grading scale. A nerve conduction test was performed and classified according to the electrophysiological severity scale. This technique is more precise than visual evaluation because it is a quantitative assessment.

Hand Pain and Sensory Deficits: Carpal Tunnel Syndrome

The Academy of Orthopaedic Physical Therapy and the Academy of Hand and Upper Extremity Physical Therapy have an ongoing effort to create evidence-based clinical practice guidelines (CPGs) for orthopaedic and sports physical therapy management and prevention of musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability and Health (ICF). This particular guideline focuses on hand pain and sensory deficits in carpal tunnel syndrome. J Orthop Sports Phys Ther 2019;49(5):CPG1-CPG85. doi:10.2519/jospt.2019.0301.

Correlation of ultrasound cross-sectional area of the median nerve, nerve conduction studies and 2-point discrimination

INTRODUCTION

The purpose of this study was to determine the correlation between a measure of physical performance, a measure of physiology and a measure of anatomy in the setting of carpal tunnel syndrome (CTS).

METHODS

A retrospective review of 215 consecutive patients with suspected CTS was conducted. All patients were evaluated with static 2-point discrimination (2PD), ultrasound (US) measurement of the median nerve cross-sectional area (CSA), and nerve conduction studies (NCS). Correlations between 2PD and US and NCS parameters were calculated. The ability of US/NCS to predict 2PD was evaluated.

RESULTS

Analysis failed to prove a statistically significant correlation between 2PD and median nerve CSA. A weak correlation was detected between 2PD and NCS parameters. When 2PD was used as a reference standard, NCS parameters combined had the greatest sensitivity, followed by US.

CONCLUSIONS

Currently used diagnostic tests (NCS and US) correlate poorly with 2PD. Muscle Nerve 000: 000-000, 2018 Muscle Nerve 59:236-239, 2019.

What is the role of Semmes-Weinstein monofilament testing in the diagnosis of electrophysiologically graded carpal tunnel syndrome?

[Purpose] The aim of the study was to investigate the ability of Semmes-Weinstein Monofilament testing to detect carpal tunnel syndrome, as well as moderate-to-severe carpal tunnel syndrome using varying thresholds and methods. [Subjects] Clinical and electrophysiological data of 62 patients (124 hands) with a mean age of 49.09±10.5 years were evaluated in this study. [Methods] Sensitivity and specificity were calculated according to two threshold values (2.83 and 3.22) and two methods, a conventional method and an internal comparison method. A threshold value of 3.22 was also used to determine sensitivity and specificity in the diagnosis of electrophysiologically moderate-to-severe carpal tunnel syndrome. Data of the first three digits were averaged to reveal the mean strength value of the monofilaments for each hand. [Results] The criteria of 2.83-conventional method yielded a sensitivity of 98% and a specificity of 17% in the diagnosis of carpal tunnel syndrome. The threshold value of 3.22 using a conventional method was found to detect moderate-to-severe carpal tunnel syndrome with high sensitivity (80%) and excellent specificity (93%). A statistically significant difference was observed in the mean strength values of the monofilaments in moderate-to-severe carpal tunnel syndrome hands and hands without carpal tunnel syndrome. [Conclusion] The current study demonstrated that Semmes-Weinstein monofilament testing might be a valuable quantitative method for detecting moderate-to-severe carpal tunnel syndrome.

Neuropsychiatric manifestations in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic disease characterized by persistent synovitis, systemic inflammation, and the presence of autoantibodies. Neuropsychiatric manifestations are quite common in RA, including depression, cognitive dysfunction, behavior changes, spinal cord compression and peripheral nerve involvement. Potential causes include systemic inflammatory process, neural compression due to bone and joint destruction, side effects of medications and copying difficulties due to the chronicity of the disease. A high level of suspicious is required for an adequate diagnosis and treatment. In this review, we will discuss topographically the main neuropsychiatric manifestations described in RA patients, in an attempt to help in the management of these complex and multifaceted disease.

Carpal tunnel syndrome and work

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome, and it frequently presents in working-aged adults. Its mild form causes 'nuisance' symptoms including dysaesthesia and nocturnal waking. At its most severe, CTS can significantly impair motor function and weaken pinch grip. This review discusses the anatomy of the carpal tunnel and the clinical presentation of the syndrome as well as the classification and diagnosis of the condition. CTS has a profile of well-established risk factors including individual factors and predisposing co-morbidities, which are briefly discussed. There is a growing body of evidence for an association between CTS and various occupational factors, which is also explored. Management of CTS, conservative and surgical, is described. Finally, the issue of safe return to work post carpal tunnel release surgery and the lack of evidence-based guidelines are discussed.

Evidence-based medicine: Carpal tunnel syndrome

LEARNING OBJECTIVES

After studying this article, the participant should be able to: (1) Describe and apply the best current high-level evidence in carpal tunnel syndrome. (2) Design a treatment plan to offer tourniquet-free, sedation-free local anesthesia for patients who wish it or who are at high risk with sedation. (3) Describe the evidence and outcomes as they relate to splinting carpal tunnel patients after surgery.

SUMMARY

This is the third Maintenance of Certification article on carpal tunnel syndrome. Hentz and Lalonde summarized the best literature in 2008 in the first article. The second article, by Shores and Lee, presented the best evidence regarding assessment, surgical treatment, and outcomes from the literature published between 1999 and 2009. In this article, the author has concentrated on topics not covered in depth in the first two articles and provides an update of the highest level evidence on important topics from 2009 to 2013. Although there is some Level IV and V evidence cited in this article, most is Level I, II, and III.

Impact of distal median neuropathy on handwriting performance for patients with carpal tunnel syndrome in office and administrative support occupations

PURPOSE

This study investigates the handwriting performance of patients with carpal tunnel syndrome (CTS) and healthy controls in office and administrative support occupations, adopting both biomechanical and functional perspectives. This work also explores how surgical intervention altered the performance of the CTS patients.

METHODS

Fourteen CTS patients and 14 control subjects were recruited to complete a self-reported survey and participate in sensory tests, hand strength, dexterity and handwriting tasks using a custom force acquisition pen along with motion capture technology. Based on the results of these, the sensory measurements, along with functional and biomechanical parameters, were used to determine the differences between the groups and also reveal any improvements that occurred in the CTS group after surgical intervention.

RESULTS

The CTS patients showed significantly poorer hand sensibility and dexterity than the controls, as well as excessive force exertion of the digits and pen tip, and less efficient force adjustment ability during handwriting. After surgery and sensory recovery, the hand dexterity and pen tip force of the CTS patients improved significantly. The force adjustment abilities of the digits also increased, but these changes were not statistically significant.

CONCLUSIONS

This study provides the objective measurements and novel apparatus that can be used to determine impairments in the handwriting abilities of office or administrative workers with CTS. The results can also help clinicians or patients to better understand the sensory-related deficits in sensorimotor control of the hand related to CTS, and thus develop and implement more suitable training or adaptive protocols.

The value of provocative tests for the wrist and elbow: a literature review

To describe and determine the usefulness of provocative tests for the wrist and elbow a literature search was performed. A total of 31 diagnostic studies were identified, assessed, and ranked. The highest ranking tests had a mean positive likelihood ratio of ≥2.0, or a mean negative likelihood ratio of ≤0.5, from more than one study. The highly recommended tests were found to be the Phalen's, Tinel's test for carpal tunnel and cubital tunnel, and modified compression test, scaphoid shift test, and elbow flexion test. A total of 14 tests met our requirements to be considered a recommended test. A greater number of provocative tests either do not have adequate data to support their usefulness or their clinical utility has not been assessed. This information may assist hand therapists in choosing which provocative tests are considered clinically useful in improving the probability of the presence or absence of pathology in the hand, wrist, and elbow.

LEVEL OF EVIDENCE

NA.

Value of Gilliatt's pneumatic tourniquet test for diagnosis of carpal tunnel syndrome

OBJECTIVES

In 1953, Gilliatt and Wilson described the pneumatic-tourniquet test to diagnose the carpal tunnel syndrome (CTS). It was originally carried out by inflating a brachial cuff at suprasystolic pressure, looking for the appearance of dysesthesiae; several authors later proposed to perform it at infrasystolic pressure, arguing that it would better reflect the elevated venous pressure supposed to be present in CTS. The purpose of this study was to compare both methods.

METHODS

This prospective randomized controlled study included 49 patients and compared both methods to perform Gilliatt's test with more commonly used provocative tests (Tinel, Phalen, Durkan, and Weber). The following end-points were considered: typical clinical presentation, altered neurophysiological tests, abnormal ultrasound findings and early resolution of symptoms after surgical decompression.

RESULTS

For all these end-points, no significant difference was observed in sensibility nor specificity, whether Gilliatt's test was performed supra- or infra-systolic. In addition, Gilliatt's test proved to have less diagnostic value than Phalen and Durkan tests for sensibility.

CONCLUSION

This study did not permit to distinguish the two versions of Gilliatt's test but to open a discussion about the utility of such a test to diagnose the CTS.

Comparison of research case definitions for carpal tunnel syndrome

OBJECTIVE

The aim of this study was to assess agreement between different case definitions of carpal tunnel syndrome (CTS) for epidemiological studies.

METHODS

We performed a literature search for papers suggesting case definitions for use in epidemiological studies of CTS. Using data elements based on symptom questionnaires, hand diagrams, physical examinations, and nerve conduction studies collected from 1107 newly-hired workers, each subject in the study was classified according to each of the case definitions selected from the literature. We compared each case definition to every other case definition, using the Kappa statistic to measure pair-wise agreement on whether each subject met the case definition.

RESULTS

We found six unique papers in a 20-year period suggesting a case definition of CTS for use in population-based studies. We extracted seven case definitions. Definitions included different parameters: (i) symptoms only, (ii) symptoms and physical examination, (iii) symptoms and either physical examination or median nerve conduction study, and (iv) symptoms and nerve conduction study. When applied to our study population, the prevalence of CTS using different case definitions ranged from 2.5-11.0%. The percentage of misclassification was between 1-10%, with generally acceptable levels of agreement (kappa values ranged from 0.30-0.85).

CONCLUSIONS

Different case definitions resulted in widely varying prevalences of CTS. Agreement between case definitions was generally good, particularly between those that required very specific symptoms or the combination of symptoms and physical examination or nerve conduction. The agreement observed between different case definitions suggests that the results can be compared across different research studies of risk factors for CTS.

Physical examination has a low yield in screening for carpal tunnel syndrome

BACKGROUND

physical examination is often used to screen workers for carpal tunnel syndrome (CTS). In a population of newly hired workers, we evaluated the yield of such screening.

METHODS

our study population included 1,108 newly hired workers in diverse industries. Baseline data included a symptom questionnaire, physical exam, and bilateral nerve conduction testing of the median and ulnar nerves; individual results were not shared with the employer. We tested three outcomes: symptoms of CTS, abnormal median nerve conduction, and a case definition of CTS that required both symptoms and median neuropathy.

RESULTS

of the exam measures used, only Semmes-Weinstein sensory testing had a sensitivity value above 31%. Positive predictive values were low, and likelihood ratios were all under 5.0 for positive testing and over 0.2 for negative testing.

CONCLUSION

physical examination maneuvers have a low yield for the diagnosis of CTS in workplace surveillance programs and in post-offer, pre-placement screening programs.

Is there Light at the End of the Tunnel? Controversies in the Diagnosis and Management of Carpal Tunnel Syndrome

Carpal tunnel syndrome is a common disorder responsible for considerable patient suffering and cost to health services. Despite extensive research, controversies still exist with regards to best practice in diagnosis, treatment, and service provision. Current best practise would support the use of history, examination and electro-diagnostic studies. The role for ultrasound scanning in diagnosis of carpal tunnel syndrome is yet to be proven. It appears magnetic resonance image scanning has a role where a rare cause for carpal tunnel syndrome may be suspected and also in the detailed reconstruction of the anatomy to aid endoscopic procedures. Treatment options can be surgical or non-surgical and patient choice will dictate the decision. For non-surgical interventions many options have been trialled but until now only steroid use, acupuncture, and splinting have shown discernable benefits. Open surgical decompression of the carpal tunnel appears to be more simple and cost-effective than minimally invasive interventions. For those patients who reject surgery, splinting, acupuncture, and steroid injection can play a role. Recent work looking at different service delivery options has shown some positive results in terms of decreasing patient waiting time for definitive treatment. However, no formal cost-effectiveness analysis has been published and concerns exist about the impact of a stream-lined service on surgical training. In this review, we look at the different diagnostic and treatment options for managing carpal tunnel syndrome. We then consider the different service delivery options and finally the cost-effectiveness evidence.

Individual finger sensibility in carpal tunnel syndrome

PURPOSE

Sensibility testing plays a role in the diagnosis of carpal tunnel syndrome (CTS). No single physical examination test has proven to be of critical value in the diagnosis, especially when compared with electrodiagnostic testing (EDX). The purpose of this study was to define which digits are most affected by CTS, both subjectively and with objective sensibility testing.

METHODS

A prospective series of 35 patients (40 hands) with EDX-positive, isolated CTS were evaluated preoperatively using 2 objective sensibility tests: static 2-point discrimination (2PD) and abbreviated Semmes-Weinstein monofilament (SWMF) testing. Detailed surveys of subjective symptoms were also collected.

RESULTS

Patients identified the middle finger as the most symptomatic over all others (51%). Objective 2PD results of each digit mirrored the subjective data, with higher values for the middle finger (mean 6.07 mm, (p < .0001). Values for the index finger failed to show a significant difference from the ulnar-innervated small finger. The most symptomatic finger matched 2PD results in over two thirds of patients. The SWMF testing showed similar, statistically significant results (middle > thumb > index > small). Correlations failed between EDX, symptoms, and SWMF results or 2PD in the index finger. Positive but weak correlation (p = .002, r = .42) was found between EDX and 2PD only in the middle fingers.

CONCLUSIONS

The middle finger is the most likely to show changes in 2PD in patients with positive EDX findings for CTS. Middle finger 2PD is best able to correlate with EDX when compared with 2PD of other digits. The SWMF testing also shows the middle digit testing as more sensitive, but this finding may be difficult to use clinically.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic I.

Diagnostic strategies using physical examination are minimally useful in defining carpal tunnel syndrome in population-based research studies

OBJECTIVE

We evaluated the utility of physical examination manoeuvres in the prediction of carpal tunnel syndrome (CTS) in a population-based research study.

METHODS

We studied a cohort of 1108 newly employed workers in several industries. Each worker completed a symptom questionnaire, a structured physical examination and nerve conduction study. For each hand, our CTS case definition required both median nerve conduction abnormality and symptoms classified as "classic" or "probable" on a hand diagram. We calculated the positive predictive values and likelihood ratios for physical examination manoeuvres in subjects with and without symptoms.

RESULTS

The prevalence of CTS in our cohort was 1.2% for the right hand and 1.0% for the left hand. The likelihood ratios of a positive test for physical provocative tests ranged from 2.0 to 3.3, and those of a negative test from 0.3 to 0.9. The post-test probability of positive testing was <50% for all strategies tested.

CONCLUSION

Our study found that physical examination, alone or in combination with symptoms, was not predictive of CTS in a working population. We suggest using specific symptoms as a first-level screening tool, and nerve conduction study as a confirmatory test, as a case definition strategy in research settings.

Assessing the accuracy of a combination of clinical tests for identifying carpal tunnel syndrome

The aim of the study was to investigate whether a combination of selected provocative manoeuvres and sensory testing could improve the accuracy of clinical diagnosis of carpal tunnel syndrome (CTS). Prospective studies were undertaken in 43 of 296 consecutive patients who were referred with suspected CTS and had undergone nerve conduction studies (NCS). Responses to Phalen's test, a modified carpal compression test (MCCT), and sensory testing over the thenar eminence were assessed for each patient. For each test (Phalen's; MCCT), sensitivity (0.64; 0.14), specificity (0.75; 0.96), positive likelihood ratio (PLR) (2.54; 3.64) and negative likelihood ratio (NLR) (0.49; 0.89) were calculated. The inclusion of sensory testing did not improve sensitivity (0.55; 0.13), specificity (0.75; 0.96), PLR (2.22; 3.29) or NLR (0.60; 0.91). These data indicate that assessment of thenar sensation does not improve the diagnostic accuracy of CTS. However, a positive Phalen's test is more likely to be associated with NCS changes that are consistent with CTS.

Predicting short-term response to thrust and nonthrust manipulation and exercise in patients post inversion ankle sprain

STUDY DESIGN

Prospective-cohort/predictive-validity study.

OBJECTIVES

To develop a clinical prediction rule (CPR) to identify patients who had sustained an inversion ankle sprain who would likely benefit from manual therapy and exercise.

BACKGROUND

No studies have investigated the predictive value of items from the clinical examination to identify patients with ankle sprains likely to benefit from manual therapy and general mobility exercises.

METHODS AND MEASURES

Consecutive patients with a status of post inversion ankle sprain underwent a standardized examination followed by manual therapy (both thrust and nonthrust manipulation) and general mobility exercises. Patients were classified as having experienced a successful outcome at the second and third sessions based on their perceived recovery. Potential predictor variables were entered into a stepwise logistic regression model to determine the most accurate set of variables for prediction of treatment success.

RESULTS

Eighty-five patients were included in the data analysis, of which 64 had a successful outcome (75%). A CPR with 4 variables was identified. If 3 of the 4 variables were present the accuracy of the rule was maximized (positive likelihood ratio, 5.9; 95% CI: 1.1, 41.6) and the posttest probability of success increased to 95%.

CONCLUSIONS

The CPR provides the ability to a priori identify patients with an inversion ankle sprain who are likely to exhibit rapid and dramatic short-term success with a treatment approach, including manual therapy and general mobility exercises.

LEVEL OF EVIDENCE

Prognosis, level 2b.

An introduction to evidence-based practice for hand surgeons and therapists

Evidence-based practice is a methodical approach to clinical practice where experience, best research evidence, and patient goals and values are integrated to make optimal decisions when making a diagnosis, selecting a diagnostic test, picking an intervention or determining prognosis. There are five steps in this process. Hand surgeons and therapists can use the evidence-based process to attain optimal management of individual patients, manage their overall practice, guide the ongoing professional development, and deal with funding and policy makers.

Using evidence-based practice to select diagnostic tests

Diagnosis is a primary activity of hand surgeons and therapists. Diagnostic tests can be used to assist in "ruling in" or "ruling out" a condition to best direct prognosis and treatment. However, the assigning of the diagnostic label is not always obvious. Principles of evidence-based practice may help hand care professionals improve their practice in the diagnosis of their patients. Evidence-based practice can be defined in terms of five steps that serve the structure for decision making and ensure optimum use of clinicians' expertise in the diagnosis.

Diagnosing soft tissue rheumatic disorders of the upper limb in epidemiological studies of vibration-exposed populations

OBJECTIVES

To investigate approaches adopted to diagnose soft tissue rheumatic disorders of the upper limb (ULDs) in vibration-exposed populations and in other settings, and to compare their methodological qualities.

METHODS

Systematic searches were made of the Medline, Embase, and CINAHL electronic bibliographic databases, and of various supplementary sources (textbooks, reviews, conference and workshop proceedings, personal files). For vibration-exposed populations, qualifying papers were scored in terms of the provenance of their measuring instruments (adequacy of documentation, standardisation, reliability, criterion-related and content validity). Similar criteria were applied to general proposals for whole diagnostic schemes, and evidence was collated on the test-retest reliability of symptom histories and clinical signs.

RESULTS

In total, 23 relevant reports were identified concerning vibration-exposed populations--21 involving symptoms and 9 involving examination/diagnosis. Most of the instruments employed scored poorly in terms of methodological quality. The search also identified, from the wider literature, more than a dozen schemes directed at classifying ULDs, and 18 studies of test-retest reliability of symptoms and physical signs in the upper limb. Findings support the use of the standardised Nordic questionnaire for symptom inquiry and suggest that a range of physical signs can be elicited with reasonable between-observer agreement. Four classification schemes rated well in terms of content validity. One of these had excellent documentation, and one had been tested for repeatability, agreement with an external reference standard, and utility in distinguishing groups that differed in disability, prognosis and associated risk factors.

CONCLUSIONS

Hitherto, most studies of ULDs in vibration-exposed populations have used custom-specified diagnostic methods, poorly documented, and non-stringent in terms of standardisation and supporting evidence of reliability and/or validity. The broader literature contains several question sets and procedures that improve upon this, and offer scope in vibration-exposed populations to diagnose ULDs more systematically.

Subacute Nerve Compressions after Trauma and Surgery of the Hand

BACKGROUND

It is accepted that major injuries of the upper limb may require not only fasciotomies but also nerve decompressions. That nerve compression(s) may occur after less dramatic injuries and "routine" surgery distal to the elbow is less well documented in the literature but well known to experienced clinicians. The aim of this study was to identify a possible link between injuries or elective surgery to the distal upper limb and "subacute nerve compressions."

METHODS

Over a 5-year period, data of patients who developed clinical symptoms of nerve compressions distal to the elbow within 6 months after trauma or elective surgery to the same upper limb that affected postoperative management were collected prospectively.

RESULTS

This study identified 91 patients (49 after trauma and 42 after elective surgery). Compression of the median nerve in the carpal tunnel was the most common syndrome (73 cases). Fasciectomy for Dupuytren's disease was the most frequent operation involved (23 cases). The average time from injury or surgery to diagnosis of nerve compression(s) was 8 weeks (range, 1 to 24 weeks). Surgical decompression of the involved nerves was performed in 43 patients (47.2 percent), with an average time from diagnosis to surgery of 30.4 weeks (range, 28 to 44 weeks). In the carpal tunnel syndrome group (47 men and 26 women), mean age was 49 years (men, 48 years; women, 50 years) and the male-to-female ratio was 1.8:1.

CONCLUSION

Subacute nerve compressions should be considered as a complication during the recovery period after injury and surgery of the upper limb.

Carpal tunnel syndrome--a comprehensive review

PURPOSE

To provide a comprehensive review of the management of carpal tunnel syndrome.

METHODS AND RESULTS

A systematic literature review is provided of the history, anatomy, pathophysiology, epidemiology, diagnostic criteria, investigative surgical techniques, results and complications for carpal tunnel syndrome.

CONCLUSION

Surgery for carpal tunnel syndrome requires meticulous attention to history-taking, investigation, counseling, training and surgical technique if unsatisfactory results and complications are to be avoided.

Diagnosing carpal tunnel syndrome—clinical criteria and ancillary tests

Damage to the median nerve within the carpal tunnel gives rise to carpal tunnel syndrome (CTS), which is associated with a wide spectrum of symptoms. The predominant classic symptoms are nocturnal pain of the hand, and sensory disturbances within the distribution of the median nerve, both of which are characteristically relieved by hand movements. Ancillary tests, including nerve conduction studies (NCS) and imaging techniques, are mainly indicated when the classic defining features are absent. NCS are less accurate in the early stages of CTS, and in younger patients. Imaging tests (ultrasound and MRI), while still having a lower diagnostic accuracy than NCS, are proving to be useful for explaining persistence of symptoms following surgical relief. Supplementary tests of small nerve fiber function and measurement of intracarpal pressure might, in the future, improve early recognition of CTS, especially in the absence of well-defined symptoms.

The thenar index: an objective assessment and classification of thenar atrophy based on static hand imprints and clinical implications

BACKGROUND

The aims of this study were to test the effectiveness of the subjective clinical evaluation and to search for any possibility of constituting an objective assessment system for the diagnosis of thenar atrophy based on static hand imprints.

METHODS

Static hand imprints were obtained from normal subjects (group A, n = 116) and carpal tunnel syndrome patients with thenar atrophy (group B, n = 26). Thenar index and the bilateral thenar index ratio were defined. Cutoff values were considered by analyses with receiver operating characteristic curves.

RESULTS

No statistically significant difference could be demonstrated in thenar index values of dominant and nondominant hands between genders and age groups (p > 0.05). A statistically significant difference was observed between severity groups in group B (p < 0.05). There was a statistically significant difference between thenar index and bilateral thenar index ratio values of groups A and B (p < 0.05). Cutoff values were considered a thenar index of 31 and a bilateral thenar index ratio of 0.8, which revealed acceptable specificity (95.3 percent) and sensitivity (77.4 percent). A new quantitative classification for thenar atrophy severity is proposed.

CONCLUSIONS

Understanding the true onset and natural progression of thenar atrophy can only be anticipated with the aid of an objective assessment system. Currently, this method should be regarded as a system for patient records and comparison for presurgical and postsurgical data. The authors believe that the thenar index classification has some merit for future use. It seems that additional objective and scientific evaluation systems and novel approaches are still needed to demystify the true nature of carpal tunnel syndrome.

Determining the Sensitivity and Specificity of Common Diagnostic Tests for Carpal Tunnel Syndrome Using Latent Class Analysis

BACKGROUND

The accuracy of a diagnostic test used to classify a patient as having disease or being disease-free is a valuable piece of information to be used by the physician when making treatment decisions. If a standard reference test is available, determining the sensitivity and specificity of a new test is straightforward. However, if that reference test is incorrectly assumed to be perfectly sensitive and specific, the errors of the reference test can result in an underestimation of the accuracy of the test being evaluated. Latent class analysis can be applied to determine the sensitivity and specificity of a new test when no standard exists.

METHODS

Latent class analysis was used to determine the accuracy rates of three commonly used measures of carpal tunnel syndrome: Tinel's sign, Phalen's test, and the nerve conduction velocity test. Data included 162 wrists from 81 patients seeking treatment for symptoms associated with carpal tunnel syndrome.

RESULTS

Tinel's sign and Phalen's test were both highly sensitive (0.97 and 0.92, respectively) and specific (0.91 and 0.88, respectively). The sensitivity and specificity of the nerve conduction velocity test were 0.93 and 0.87, respectively.

CONCLUSION

Estimates of the sensitivity and specificity of these common tests for carpal tunnel syndrome support their widespread clinical use.

Development of a clinical prediction rule for the diagnosis of carpal tunnel syndrome

OBJECTIVES

To develop a clinical prediction rule (CPR) and to assess the reliability and diagnostic accuracy of individual clinical examination items for the diagnosis of carpal tunnel syndrome (CTS).

DESIGN

Prospective diagnostic test study with blind comparison to a reference criterion of a compatible clinical presentation and abnormal electrophysiologic findings.

SETTING

Multicenter medical center and community hospital with patient referrals from ambulatory primary care and specialty practice settings.

PARTICIPANTS

Eight-two consecutively referred patients (50% men; mean age, 45+/-12 y) with suspected cervical radiculopathy or CTS referred for electrophysiologic examination.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Sensitivity, specificity, and likelihood ratios.

RESULTS

The CPR identified in this study consisted of 1 question (shaking hands for symptom relief), wrist-ratio index greater than .67, Symptom Severity Scale score greater than 1.9, reduced median sensory field of digit 1, and age greater than 45 years. The likelihood ratio for the CPR was 18.3 when all 5 tests were positive. Interrater reliability was acceptable for all but 2 clinical examination items.

CONCLUSIONS

The CPR identified was more useful for the diagnosis of CTS than any single test item and resulted in posttest probability changes of up to 56%. Further investigation is required both to validate the test-item cluster and to improve point-estimate precision.

Clinical diagnosis of carpal tunnel syndrome: a systematic review

The purposes of this systematic review were to examine the properties of clinical tests used in the diagnosis of carpal tunnel syndrome (CTS) and to provide estimates of their sensitivity and specificity. A literature search was conducted using two databases-PubMed and the Cumulative Index to Nursing and Allied Health Literature (CINAHL)-from 1986 to June 2003, and hand-searching reference lists of retrieved articles. Two reviewers evaluated the papers for quality using an evaluation tool developed by one of the authors. Estimates of sensitivity and specificity were determined by averaging values across studies weighted by sample size. Although 60 studies were reviewed in detail, many were of poor quality (mean quality score was 6.6 of 12, with only 15 of 60 obtaining a score of 8 or greater). The most frequently studied test was Phalen's, with an overall estimate of 68% sensitivity and 73% specificity. Next was Tinel's, with estimates of 50% and 77%, and then carpal compression, with estimates of 64% and 83% for sensitivity and specificity, respectively. Two-point discrimination and testing of atrophy or strength of the abductor pollicis brevis proved to be specific but not very sensitive. The estimates determined in this review should help therapists choose clinical tests with the appropriate balance of sensitivity and specificity required for diagnosing carpal tunnel syndrome in their specific clinical environments.

Clinical and electrodiagnostic testing of carpal tunnel syndrome: a narrative review

Carpal Tunnel Syndrome (CTS) is a pressure-induced neuropathy that causes sensorimotor disturbances of the median nerve, which impair functional ability. A clear history that elicits relevant personal and work exposures and the nature of symptoms can lead to a high probability of a correct diagnosis. Hand diagrams and diagnostic questionnaires are available to provide structure to this process. A variety of provocative tests have been described and have variable accuracy. The Phalen's wrist flexion and the carpal compression tests have the highest overall accuracy, while Tinel's nerve percussion test is more specific to axonal damage that may occur as a result of moderate to severe CTS. Sensory evaluation of light touch, vibration, or current perception thresholds can detect early sensory changes, whereas 2-point discrimination changes and thenar atrophy indicate loss of nerve fibers occurring with more severe disease. Electrodiagnosis can encompass a variety of tests and is commonly used to assess the presence/severity of neuropathic changes and to preclude alternative diagnoses that overlap with CTS in presentation. The pathophysiologic changes occurring with different stages of nerve compression must be considered when interpreting diagnostic test results and predicting response to physical therapy management.

The relationship among five common carpal tunnel syndrome tests and the severity of carpal tunnel syndrome

The purpose of this research was to examine the relationship among clinical carpal tunnel syndrome (CTS) tests and the severity of CTS. A total of 66 subjects with electrodiagnostically confirmed CTS were tested on five CTS tests, then classified according to the severity of CTS. An association was found between testing positive on Phalen's test and the severity of CTS (p < 0.05). In contrast, no association was found between the severity of CTS and results on Tinel's sign, manual version of the carpal compression test (mCCT), Katz-Stirrat hand diagram, or carpal tunnel outcomes assessment tool. The more severe the CTS, the more likely one is to test positive on Phalen's test. Tinel's sign and the mCCT are not influenced by the severity of CTS. This study suggests that Tinel's sign and mCCT may not be useful in assessing the effectiveness of treatment. The Katz-Stirrat hand diagram and the carpal tunnel outcomes assessment tool are not influenced by the severity of CTS, indicating that numerous factors can influence a patient's response on subjective questionnaires.

Clinical examination as a tool for identifying the origin of regional musculoskeletal pain

A knowledge of the physiopathology of the processing of noxious stimuli in regional musculoskeletal disorders is useful for an understanding of the clinical history. In regional musculoskeletal pain (RMP) the physiopathology of the pain may be separated into two main features. First, the nociceptive pain which results from the activation of nociceptors diffusely distributed among the anatomical structures in and around the joint, apart from the cartilage; the nociceptive pain has a protective role. Second, the abnormal impulses from a nervous tissue lesion give rise to a neuropathic pain which offers no biological advantage and is a maladaptive pain. This chapter describes the main physiological characteristics of these two kinds of pain. From these, in the majority of cases, the clinical history and the physical examination must specify the diagnosis of the RMP and localize the source of pain. Furthermore, the clinical characteristics permit diagnosis of different complex situations where these two types of pain are associated.

Aberrant protective force generation during neural provocation testing and the effect of treatment in patients with neurogenic cervicobrachial pain

BACKGROUND

Observation of the occurrence of protective muscle activity is advocated in assessment of the peripheral nervous system by means of neural provocation tests. However, no studies have yet demonstrated abnormal force generation in a patient population.

OBJECTIVES

To analyze whether aberrations in shoulder girdle-elevation force during neural tissue provocation testing for the median nerve (NTPT1) can be demonstrated, and whether possible aberrations can be normalized following cervical mobilization.

STUDY DESIGN

A single-blind randomized comparative controlled study.

SETTING

Laboratory setting annex in a manual therapy teaching practice.

PARTICIPANTS

Twenty patients with unilateral or bilateral neurogenic cervicobrachial pain.

METHODS

During the NTPT1, we used a load cell and electrogoniometer to record continuously the shoulder-girdle elevation force in relation to the available range of elbow extension. Following randomization, we analyzed the immediate treatment effects of a cervical contralateral lateral glide mobilization technique (experimental group) and therapeutic ultrasound (control group).

RESULTS

On the involved side, the shoulder-girdle elevation force occurred earlier, and the amount of force at the end of the test was substantially, though not significantly, greater than that on the uninvolved side at the corresponding range of motion. Together with a significant reduction in pain perception after cervical mobilization, a clear tendency toward normalization of the force curve could be observed, namely, a significant decrease in force generation and a delayed onset. The control group demonstrated no differences.

CONCLUSIONS

Aberrations in force generation during neural provocation testing are present in patients with neurogenic pain and can be normalized with appropriate treatment modalities.

Lack of utility of Semmes-Weinstein monofilament testing in suspected carpal tunnel syndrome

OBJECTIVE

To investigate the value of Semmes-Weinstein monofilament (SWM) testing in patients with electrodiagnostically confirmed carpal tunnel syndrome in a group of patients with symptoms compatible with carpal tunnel syndrome.

DESIGN

A total of 119 consecutive patients with symptoms compatible with carpal tunnel syndrome were assessed. Blinded comparison of two Semmes-Weinstein monofilament testing protocols with orthodromic midpalm electrodiagnostic testing was performed. The electrodiagnostic test was considered the standard to which the results of the Semmes-Weinstein monofilament testing were measured.

RESULTS

Fifty three percent of our patients had electrodiagnostically confirmed carpal tunnel syndrome. Using a conservative Semmes-Weinstein monofilament testing protocol the sensitivity was 98% and the specificity was 15%. The positive predictive value was 56% and the negative predictive value was 88%. Using a liberal Semmes-Weinstein monofilament testing protocol the sensitivity was 13% and the specificity was 88%. The positive predictive value was 53% and the negative predictive value was 47%.

CONCLUSION

Semmes-Weinstein monofilament testing was not shown to have utility in diagnosing electrodiagnostically confirmed carpal tunnel syndrome in our population of predominantly male veterans.

Splinting or surgery for carpal tunnel syndrome? Design of a randomized controlled trial [ISRCTN18853827]

BACKGROUND

Carpal tunnel syndrome is a common disorder, which can be treated with surgery or conservative options. However, there is insufficient evidence and no consensus among physicians with regard to the preferred treatment for carpal tunnel syndrome. Therefore, a randomized controlled trial is conducted to compare the short- and long-term efficacy of surgery and splinting in patients with carpal tunnel syndrome. An attempt is also made to avoid the (methodological) limitations encountered in earlier trials on the efficacy of various treatment options for carpal tunnel syndrome.

METHODS

Patients of 18 years and older, with clinically and electrophysiologically confirmed idiopathic carpal tunnel syndrome, are recruited by neurologists in 13 hospitals. Patients included in the study are randomly allocated to either open carpal tunnel release or wrist splinting during the night for at least 6 weeks. The primary outcomes are general improvement, waking up at night and severity of symptoms (main complaint, night and daytime pain, paraesthesia and hypoesthesia). Outcomes are assessed up to 18 months after randomization.