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

National trends in the initial diagnosis and management of carpal tunnel syndrome: results from the ELECTS (ELEctrophysiology in Carpal Tunnel Syndrome) study

INTRODUCTION

The optimal role of nerve conduction studies (NCS) in management of carpal tunnel syndrome (CTS) is unclear, with no standardised guidance. This study aimed to identify variation in practice in the initial diagnosis of patients with suspected CTS, alongside evaluating how NCS findings influence clinical decision making.

METHODS

A national multicentre collaborative survey was conducted in 2021. All centres providing surgery for CTS were invited to participate, primarily via social media. All middle-senior grade orthopaedic/plastic surgeons and advanced care practitioners that regularly manage new referrals for suspected CTS were eligible to respond. Local representatives at each participating site submitted their responses to a central team who collated and analysed the results.

RESULTS

A total of 137 healthcare professionals responded from 18 UK NHS Trusts. Of these 137, 124 (91%) reported not employing any validated clinical questionnaires in their routine practice, preferring to rely on clinical diagnosis and/or NCS if available, whereas 84 (61%) utilised NCS to aid diagnosis, with significant differences among professionals with differing experience (p < 0.01). The most common methods for determining the severity of CTS were history, examination and NCS. In symptomatic CTS with confirmatory NCS, over 50% of clinicians would choose surgical decompression as their first-line intervention. In cases of either negative NCS or atypical presentation, 37% and 51%, respectively, would consider conservative management (e.g. splintage) or steroid injection first line.

CONCLUSIONS

With growing waiting lists for NCS and surgery, national consensus guidelines should be developed to support decision making, while maximising efficient utilisation of increasingly constrained resources.

Assessment of the carpal tunnel and associated neural structures with superb microvascular imaging: a scoping review

INTRODUCTION

Superb microvascular imaging (SMI) is an advanced ultrasound technique that portrays microcirculation. Its clinical applications have been studied in various diseases, including carpal tunnel syndrome (CTS) i.e. the most common entrapment neuropathy. This scoping review explores the role of SMI in diagnosing CTS or the assessment of relevant neural structures.

METHODS

We conducted a comprehensive search of electronic databases (PubMed, Embase and Web of Science) up to 26 September 2023. Two independent authors conducted the literature search, quality assessment, and data extraction.

RESULTS

This review includes seven studies comprising 385 wrists. SMI consistently revealed increased intraneural vascularity in the median nerves of patients with CTS compared to healthy individuals. While SMI demonstrated higher sensitivity than traditional Doppler methods for detecting CTS, its specificity was somewhat lower. Combining SMI with B-mode ultrasound appears to enhance the diagnostic accuracy for CTS. However, the relationship between SMI findings and CTS severity remains unclear.

CONCLUSIONS

This review highlighted the ability of SMI to provide detailed vascular structures in both healthy wrists and those with CTS. Additional research is crucial to determine the typical SMI findings of the carpal tunnel and within that context, tailor more precise diagnostic/therapeutic applications for the CTS population.

Sensitivity and Specificity of Examination Maneuvers for Carpal Tunnel Syndrome: A Meta-Analysis

Our purpose was to assess the diagnostic validity (sensitivity (Sn) and specificity (Sp)) of physical examination maneuvers for carpal tunnel syndrome (CTS). This meta-analysis utilized the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Studies assessing exam maneuvers (including components of the CTS-6) for CTS were identified in MEDLINE (Medical Literature Analysis and Retrieval System Online) and Embase (Excerpta Medica Database) databases. Assessed maneuvers assessed included: Phalen's test, Tinel's sign, Durkan test, scratch-collapse test, Semmes-Weinstein monofilament (SWM), and static 2-point discrimination (2PD) test. Data extracted included: article name, total number of subjects/hands, type of exam, and exam Sn/Sp. Forest plots were presented to display the estimated Sn/Sp and boxplots were used to demonstrate the locality, spread, and skewness of the Sn/Sp through the quartiles. After screening 570 articles, 67 articles involving 8924 hands were included. Forty-eight articles assessed Phalen's test, 45 assessed Tinel's sign, 21 assessed the Durkan test, seven assessed the scratch-collapse test, 11 assessed SWM, and six assessed the static 2PD test. Phalen's test demonstrated the greatest median Sn (0.70, (Q1, Q3): (0.51, 0.85)), followed by the Durkan test (0.67, (Q1, Q3): (0.46, 0.82)). 2PD demonstrated the highest median Sp (0.90, (Q1, Q3): (0.88, 0.90)), followed by SWM (0.85, (Q1, Q3): (0.51, 0.89)). There is considerable variability with respect to the validity of physical exam tests used in the diagnosis of CTS. Upper-extremity surgeons should be aware of inherent limitations for individual exam maneuvers. In the absence of a uniformly accepted diagnostic gold standard, a combination of exams, along with pertinent patient history, should guide the diagnosis of CTS.

Diagnostic Test Accuracy of Provocative Maneuvers for the Diagnosis of Carpal Tunnel Syndrome: A Systematic Review and Meta-Analysis

OBJECTIVE

The purpose of this study was to summarize and evaluate the research on the accuracy of provocative maneuvers to diagnose carpal tunnel syndrome (CTS).

METHODS

The MEDLINE, CINAHL, Cochrane, and Embase databases were searched, and studies that assessed the diagnostic accuracy of at least 1 provocative test for CTS were selected. Study characteristics and data about the diagnostic accuracy of the provocative tests for CTS were extracted. A random-effects meta-analysis of the sensitivity (Sn) and specificity (Sp) of the Phalen test and Tinel sign was conducted. The risk of bias (ROB) was rated using the QUADAS-2 tool.

RESULTS

Thirty-one studies that assessed 12 provocative maneuvers were included. The Phalen test and the Tinel sign were the 2 most assessed tests (in 22 and 20 studies, respectively). The ROB was unclear or low in 20 studies, and at least 1 item was rated as having high ROB in 11 studies. Based on a meta-analysis of 7 studies (604 patients), the Phalen test had a pooled Sn of 0.57 (95% CI = 0.44-0.68; range = 0.12-0.92) and a pooled Sp of 0.67 (95% CI = 0.52-0.79; range = 0.30-0.95). For the Tinel sign (7 studies, 748 patients), the pooled Sn was 0.45 (95% CI = 0.34-0.57; range = 0.17-0.97) and the pooled Sp was 0.78 (95% CI = 0.60-0.89; range = 0.40-0.92). Other provocative maneuvers were less frequently studied and had conflicting diagnostic accuracies.

CONCLUSION

Meta-analyses are imprecise but suggest that the Phalen test has moderate Sn and Sp, whereas the Tinel test has low Sn and high Sp. Clinicians should combine provocative maneuvers with sensorimotor tests, hand diagrams, and diagnostic questionnaires to achieve better overall diagnostic accuracy rather than relying on individual clinical tests.

IMPACT

Evidence of unclear and high ROB do not support the use of any single provocative maneuver for the diagnosis of CTS. Clinicians should consider a combination of noninvasive clinical diagnostic tests as the first choice for the diagnosis of CTS.

Comparison of Two Manual Therapy Programs, including Tendon Gliding Exercises as a Common Adjunct, While Managing the Participants with Chronic Carpal Tunnel Syndrome

Background

Carpal tunnel syndrome (CTS) is the symptomatic compression neuropathy of the median nerve at the wrist level that may become a reason for upper limb disability, in the women and men population.

Objective

This study aimed to compare the efficacy of the neurodynamic technique (NT) and carpal bone mobilization technique (CBMT) incorporated with tendon gliding exercises (TGE) as an effect-enhancing adjunct while managing the participants with chronic CTS.

Methods

The study followed a two-arm parallel-group randomized comparative design. Thirty participants (aged 30–59 years) with chronic CTS were recruited randomly to both the NT and CBMT groups. In addition to the TGE (a common adjunct), NT and CBMT were performed in the NT and CBMT groups, respectively, for three weeks. The primary outcome measures including pain intensity, functional status, grip strength, and motor nerve conduction study were assessed using a visual analogue scale (VAS), Boston Carpal Tunnel Questionnaire (BCTQ), hand-held dynamometer, and electromyograph, respectively, at baseline, 3 weeks postintervention, and follow-up at one week post end of the intervention. Paired and unpaired t-test were used to calculate the differences in intervention effects within and between the groups with keeping the level of significance α at 0.05.

Results

The data analysis revealed a significant (95% CI, p < 0.05) difference for all outcomes within each group compared across different time intervals. Similarly, a significant difference was found for all outcomes except pain and grip strength compared between groups at 3 weeks postintervention and follow-up at one week post end of the intervention.

Conclusions

The NT revealed more effectiveness than the CBMT when incorporated with TGE to improve nerve conduction velocity and functional status of the hand. However, both NT and CBMT were equally effective in improving pain and grip strength while managing the participants with chronic CTS. In addition, the TGE contributed as a beneficial, effect-enhancing adjunct to the NT and CBMT differently. Significance. The study will guide the physiotherapist in applying either of the combination techniques suitable for achieving treatment objectives while managing the participants with chronic CTS.

Accuracy of diagnostic clinical tests and questionnaires in screening for carpal tunnel syndrome among workers- A systematic review

OBJECTIVE

To synthesize and appraise the evidence on the diagnostic accuracy of the clinical examination tests and questionnaires for screening carpal tunnel syndrome (CTS) among workers.

DESIGN

Systematic review of diagnostic test accuracy METHODS: Electronic search of 3 online databases (CINAHL, Embase, Medline) was done on August 31, 2020. Studies reporting the diagnostic accuracy of clinical examination tests in workers, compared to a reference standard test, were included. Diagnostic accuracy measures such as sensitivity (Sn) and specificity (Sp) were extracted and reported for different clinical examination tests. The risk of bias and applicability concerns were rated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool by 2 independent reviewers. Diagnostic tests accuracy extension of the PRISMA guidelines were followed.

RESULTS

Twelve studies reporting on the diagnostic accuracy of the clinical examination tests for workers suspected of CTS were included. Fourteen different clinical examination tests were evaluated in the studies, including sensorimotor, provocative maneuvers, questionnaires, and hand symptom diagrams (HSD). Ten of the included studies had an either unclear or high risk of bias. The most accurate tests to diagnose CTS in workers were the Katz HSD (with Sn ranging from 38%-93%, and Sp ranging from 25%-89%) and Kamath and Stothard questionnaire (Sn and Sp = 100%). Combination of Katz HSD with either the Phalen's maneuver or the Tinel's sign resulted in excellent Sp (83% and 89%, respectively).

CONCLUSIONS

Low to moderate quality evidence indicates variability in individual clinical examination tests used to screen for CTS in workers. Diagnostic self-report tools consisting of hand diagrams and/or diagnostic questions provide low burden and high accuracy. Still, they require more rigorous investigation about their value alone or in combination with clinical assessment tests.

Carpal tunnel decompression in patients with normal nerve conduction studies

Some patients present with typical clinical features of carpal tunnel syndrome despite normal nerve conduction studies. This study compared the preoperative and 1-year postoperative QuickDASH scores in patients with normal and abnormal nerve conduction studies, who underwent carpal tunnel decompression. Of the 637 patients included in the study, 19 had clinical features of carpal tunnel syndrome but normal nerve conduction studies, and underwent decompression after failure of conservative management. Preoperative QuickDASH scores were comparable in both groups (58 vs 54.8). However, there were significant differences between the normal and abnormal nerve conduction study groups in the QuickDASH at 1 year (34.9 vs 21.5) and change in QuickDASH postoperatively (23.1 vs 33.4). Patients with normal nerve conduction studies had comparable preoperative disability scores compared with those with abnormal studies. Although they had a significant improvement in QuickDASH at 1 year, this was significantly less than those with abnormal nerve conduction studies. Level of evidence: III.

The prevalence of metabolic syndrome among Iranian bakers

BACKGROUND

Metabolic syndrome (MetS) is a group of risk factors that are associated with increased risk for atherosclerotic cardiovascular disease.

OBJECTIVE

The objective of this study was to determine the prevalence of metabolic syndrome and its individual components among Iranian bakery workers.

METHODS

A cross-sectional study enrolling 163 randomly selected bakery workers from Semnan province (Northeast Iran), was conducted in 2017. A standard questionnaire was used for data collection. Analyses were performed using t-test, one-way ANOVA and Latent Class Analysis (LCA) in R software.

RESULTS

The prevalence of MetS was 19.8% among bakery workers. More bakery workers with MetS had no regular exercise (p = 0.001) and worked more than eight hours a day (p = 0.001). In this study, the International Diabetes Federation (IDF) diagnostic criteria had more agreement with the American Heart Association (AHA) (49.1%) than the World Health Organization (WHO) and Adult Treatment Panel (ATP) criteria. Also, the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATPIII) had the highest sensitivity for diagnosing MetS. The sensitivity of the four diagnostic methods, WHO, IDF, ATP and AHA, were 45.2%, 61.7%, 67.9% and 64.8%; and their specificity were 98.2%, 100%, 100% and 100%, respectively.

CONCLUSION

The prevalence of MetS is high among bakery workers in Iran. Increased physical activity and intake of fruit and vegetables are recommended for the prevention of MetS.

Comparison of the accuracy of three diagnostic criteria and estimating the prevalence of metabolic syndrome: A latent class analysis

Background:

Metabolic syndrome (MetS) is a growing public health problem with a worldwide distribution, and its prevalence is rapidly increasing worldwide. Hence, this study aimed to compare the prevalence of MetS based on the International Diabetes Federation (IDF), the National Cholesterol Education Program Expert Panel Adult Treatment Panel III (NCEP ATP III), and the American Association of Clinical Endocrinologists (AACE) diagnostic criteria.

Materials and Methods:

In this cross-sectional study, a total of 4737 people aged 45–69 years were enrolled in the 2^nd phase of Shahroud Eye Cohort Study. We evaluated the prevalence of MetS with 95% confidence intervals by age and sex groups and according to MetS components. The accuracy (sensitivity and specificity) of these three methods was compared using latent class analysis. Finally, kappa statistic was used to determine the agreement between the diagnostic methods.

Results:

The prevalence of MetS varied from a minimum of 47.2% (as defined by the AACE) to a maximum of 60.0% (as defined by the IDF). The sensitivity of the three diagnostic methods of IDF, NCEP ATP III, and AACE was 98.9%, 94.4%, and 91.1%, respectively, and the specificity of these three methods was 94.6%, 97.0%, and 98.4%, respectively. Moreover, the highest agreement was found between the definition of the IDF and the NCEP ATP III.

Conclusion:

The IDF diagnostic method has a higher sensitivity for the diagnosis of MetS in Iranian middle-aged people. It is recommended to use this method for identifying more people at risk of MetS.

What Are the Applications and Limitations of Artificial Intelligence for Fracture Detection and Classification in Orthopaedic Trauma Imaging? A Systematic Review

BACKGROUND

Artificial-intelligence algorithms derive rules and patterns from large amounts of data to calculate the probabilities of various outcomes using new sets of similar data. In medicine, artificial intelligence (AI) has been applied primarily to image-recognition diagnostic tasks and evaluating the probabilities of particular outcomes after treatment. However, the performance and limitations of AI in the automated detection and classification of fractures has not been examined comprehensively.

QUESTION/PURPOSES

In this systematic review, we asked (1) What is the proportion of correctly detected or classified fractures and the area under the receiving operating characteristic (AUC) curve of AI fracture detection and classification models? (2) What is the performance of AI in this setting compared with the performance of human examiners?

METHODS

The PubMed, Embase, and Cochrane databases were systematically searched from the start of each respective database until September 6, 2018, using terms related to "fracture", "artificial intelligence", and "detection, prediction, or evaluation." Of 1221 identified studies, we retained 10 studies: eight studies involved fracture detection (ankle, hand, hip, spine, wrist, and ulna), one addressed fracture classification (diaphyseal femur), and one addressed both fracture detection and classification (proximal humerus). We registered the review before data collection (PROSPERO: CRD42018110167) and used the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We reported the range of the accuracy and AUC for the performance of the predicted fracture detection and/or classification task. An AUC of 1.0 would indicate perfect prediction, whereas 0.5 would indicate a prediction is no better than a flip-of-a-coin. We conducted quality assessment using a seven-item checklist based on a modified methodologic index for nonrandomized studies instrument (MINORS).

RESULTS

For fracture detection, the AUC in five studies reflected near perfect prediction (range, 0.95-1.0), and the accuracy in seven studies ranged from 83% to 98%. For fracture classification, the AUC was 0.94 in one study, and the accuracy in two studies ranged from 77% to 90%. In two studies AI outperformed human examiners for detecting and classifying hip and proximal humerus fractures, and one study showed equivalent performance for detecting wrist, hand and ankle fractures.

CONCLUSIONS

Preliminary experience with fracture detection and classification using AI shows promising performance. AI may enhance processing and communicating probabilistic tasks in medicine, including orthopaedic surgery. At present, inadequate reference standard assignments to train and test AI is the biggest hurdle before integration into clinical workflow. The next step will be to apply AI to more challenging diagnostic and therapeutic scenarios when there is absence of certitude. Future studies should also seek to address legal regulation and better determine feasibility of implementation in clinical practice.

LEVEL OF EVIDENCE

Level II, diagnostic study.

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.

Scratch Collapse Test for Carpal Tunnel Syndrome: A Systematic Review and Meta-analysis

Background:

Despite the fact that carpal tunnel syndrome (CTS) is the most common entrapment neuropathy, the diagnostic accuracy of clinical screening examinations for CTS is controversial. The scratch collapse test (SCT) is a novel test that may be of diagnostic advantage. The purpose of our study was to determine the diagnostic accuracy of the SCT for CTS.

Methods:

A literature search was performed using PubMed (1966 to April 2018); Ovid MEDLINE (1966 to April 2018); EMBASE (1988 to April 2018); and Cochrane Central Register of Controlled Trials (The Cochrane Library, to April 2018). We examined the studies for the pooled sensitivity, specificity, and likelihood ratios of the SCT. This review has been registered with PROSPERO (CRD42018077115).

Results:

The literature search generated 13 unique articles. Seven articles were included for full text screening and 3 articles met our inclusion criteria, all of which were level II evidence with low risk of bias (165 patients). Pooled sensitivities, specificities, positive likelihood ratio, and negative likelihood ratios were 0.32 [95% CI (0.24–0.41)], 0.62 [95% CI (0.45–0.78)], 0.75 [95% CI (0.33–1.67)], and 1.03 [95% CI (0.61–1.74)], respectively. The calculated area under the summary receiver operating characteristic (AUSROC) curve was 0.25, indicating a low diagnostic accuracy.

Conclusion:

The SCT has poor sensitivity; however, it is moderately specific. Based on the current literature and their variable quality of the evidence, we conclude that the SCT is not an adequate screening test for detecting CTS.

Compliance assessment and flip-angle measurement of the median nerve: sonographic tools for carpal tunnel syndrome assessment?

Objectives

To assess the diagnostic performance of median nerve (MN) flip-angle measurements, deformation during wrist flexion [transit deformation coefficient (TDC)], during compression [compression deformation coefficient (CDC)] and fascicular freedom to potentially identify fibrotic MN changes in patients with carpal tunnel syndrome (CTS).

Methods

This prospective study was performed with institutional review board approval; all participants provided oral and written informed consent. Wrists in 21 healthy participants and 29 patients with CTS were examined by ultrasound. MN movement during wrist flexion, MN deformation during transition over the flexor tendons (TDC) and during controlled compression (CDC) as well as fascicular freedom were assessed. Diagnostic properties of these parameters were calculated and compared to clinical findings and cross-section area measurements (ΔCSA).

Results

Low flip angles were associated with high ΔCSA at a receiver-operator characteristics area under the curve (AUC) of 0.62 (0.51-0.74). TDC [AUC, 0.83 (0.73-0.92), 76.3% (59.8-88.6%) sensitivity, 88.5% (76.6-95.7%) specificity], restricted fascicular movement [AUC, 0.86 (0.78-0.94), 89.5% (75.2-97.1%) sensitivity, 80.8% (67.5-90.4%) specificity] and compression-based CDC [AUC, 0.97 (0.94-1.00), 82.1% (66.5-92.5%) sensitivity, 94.2% (84.1-98.8%) specificity] demonstrated substantial diagnostic power (95% confidence intervals in parentheses).

Conclusions

Fascicular mobility, TDC and CDC show substantial diagnostic power and may offer insights into the underlying pathophysiology of CTS.

Key Points

• Dynamic ultrasonography during wrist flexion and compression enables median nerve deformability assessment.

• Overall, reduced median nerve deformability is highly indicative of CTS.

• Median nerve compressibility shows higher diagnostic power than conventional cross-section area measurements.

Electronic supplementary material

The online version of this article (10.1007/s00330-018-5555-3) contains supplementary material, which is available to authorized users.

Derivation and validation of a diagnostic test for irritable bowel syndrome using latent class analysis

BACKGROUND

The accuracy of symptom-based diagnostic criteria for irritable bowel syndrome (IBS) is modest.

AIMS

To derive and validate a new test that utilises latent class analysis.

METHODS

Symptom, colonoscopy, and histology data were collected from 1981 patients and 360 patients in two cohorts referred to secondary care for investigation of their gastrointestinal symptoms in Canada and the UK, respectively. Latent class analysis was used to identify naturally occurring clusters in patient-reported symptoms in the Canadian dataset, and the latent class model derived from this was then applied to the UK dataset in order to validate it. Sensitivity, specificity, and positive and negative likelihood ratios (LRs) were calculated for the latent class models.

RESULTS

In the Canadian cohort, the model had a sensitivity of 44.7% (95% CI 40.0-50.0) and a specificity of 85.3% (95% CI 83.4-87.0). Positive and negative LRs were 3.03 (95% CI 2.57-3.56) and 0.65 (95% CI 0.59-0.71) respectively. A maximum positive LR of 3.93 was achieved following construction of a receiver operating characteristic curve. The performance in the UK cohort was similar, with a sensitivity and specificity of 52.5% (95% CI 42.2-62.7) and 84.3% (95% CI 79.3-88.6), respectively. Positive and negative LRs were 3.35 (95% CI 2.38-4.70) and 0.56 (95% CI 0.45-0.68), respectively, with a maximum positive LR of 4.15.

CONCLUSIONS

A diagnostic test for IBS, utilising patient-reported symptoms incorporated into a latent class model, performs as accurately as symptom-based criteria. It has potential for improvement via addition of clinical markers, such as coeliac serology and faecal calprotectin.

Cost-Minimization Analysis of Open and Endoscopic Carpal Tunnel Release

BACKGROUND

Carpal tunnel release is the most common upper-limb surgical procedure performed annually in the U.S. There are 2 surgical methods of carpal tunnel release: open or endoscopic. Currently, there is no clear clinical or economic evidence supporting the use of one procedure over the other. We completed a cost-minimization analysis of open and endoscopic carpal tunnel release, testing the null hypothesis that there is no difference between the procedures in terms of cost.

METHODS

We conducted a retrospective review using a private-payer and Medicare Advantage database composed of 16 million patient records from 2007 to 2014. The cohort consisted of records with an ICD-9 (International Classification of Diseases, Ninth Revision) diagnosis of carpal tunnel syndrome and a CPT (Current Procedural Terminology) code for carpal tunnel release. Payer fees were used to define cost. We also assessed other associated costs of care, including those of electrodiagnostic studies and occupational therapy. Bivariate comparisons were performed using the chi-square test and the Student t test.

RESULTS

Data showed that 86% of the patients underwent open carpal tunnel release. Reimbursement fees for endoscopic release were significantly higher than for open release. Facility fees were responsible for most of the difference between the procedures in reimbursement: facility fees averaged $1,884 for endoscopic release compared with $1,080 for open release (p < 0.0001). Endoscopic release also demonstrated significantly higher physician fees than open release (an average of $555 compared with $428; p < 0.0001). Occupational therapy fees associated with endoscopic release were less than those associated with open release (an average of $237 per session compared with $272; p = 0.07). The total average annual reimbursement per patient for endoscopic release (facility, surgeon, and occupational therapy fees) was significantly higher than for open release ($2,602 compared with $1,751; p < 0.0001).

CONCLUSIONS

Our data showed that the total average fees per patient for endoscopic release were significantly higher than those for open release, although there currently is no strong evidence supporting better clinical outcomes of either technique.

CLINICAL RELEVANCE

Value-based health-care models that favor delivering high-quality care and improving patient health, while also minimizing costs, may favor open carpal tunnel release.

Median nerve behavior at different wrist positions among older males

The effect of wrist flexion-extension on the median nerve appearance, namely the cross-sectional area (MNCSA) and the longitudinal (D1) and vertical (D2) diameters, was investigated among older adults (N = 34). Ultrasound examination was conducted to examine the median nerve at different wrist angles (neutral; and 15°, 30°, and 45° extension and flexion), in both the dominant and nondominant hand. Median nerve behavior were significantly associated with wrist angle changes. The MNCSA at wrist flexion and extension were significantly smaller (P < .001) compared with the neutral position in both the dominant and nondominant hand. The D1 and D2 were significantly reduced at flexion (P < .001) and extension (P < .001), respectively, in both the dominant and nondominant hand. Our results suggest that a larger flexion-extension angle causes higher compression stress on the median nerve, leading to increased deformation of the MNCSA, D1, and D2 among older adults.

Effect of wrist angle on median nerve appearance at the proximal carpal tunnel

This study investigated the effects of wrist angle, sex, and handedness on the changes in the median nerve cross-sectional area (MNCSA) and median nerve diameters, namely longitudinal diameter (D1) and vertical diameter (D2). Ultrasound examination was conducted to examine the median nerve at the proximal carpal tunnel in both dominant and nondominant hands of men (n = 27) and women (n = 26). A total of seven wrist angles were examined: neutral; 15°, 30°, and 45° extension; and 15°, 30°, and 45° flexion. Our results indicated sexual dimorphism and bilateral asymmetry of MNCSA, D1 and D2 measurements. MNCSA was significantly reduced when the wrist angle changed from neutral to flexion or extension positions. At flexion positions, D1 was significantly smaller than that at neutral. In contrast, at extension positions, D2 was significantly smaller than that at neutral. In conclusion, this study showed that MNCSA decreased as the wrist angle changed from neutral to flexion or extension positions in both dominant and nondominant hands of both sexes, whereas deformation of the median nerve differed between wrist flexion and extension.

Changes in treatment plan for carpal tunnel syndrome based on electrodiagnostic test results

This study evaluated how often the treatment plan for carpal tunnel syndrome (CTS) changed based on electrodiagnostic test results. Secondly, we assessed factors associated with a change in the treatment plan for CTS. One-hundred-and-thirty English-speaking adult patients underwent electrodiagnostic testing in a prospective cohort study. Treatment plan was recorded before and after testing. Treatment plan changed in 25 patients (19%) based on electrodiagnostic test results. The plan for operative treatment before testing decreased significantly after testing (83% versus 72%). The best logistic regression model for no change in treatment plan included a prolonged or non-recordable median distal sensory latency (normal, prolonged, or non-recordable), and explained 24% of the variation. For surgeons that manage CTS on the basis of objective pathophysiology rather than symptoms, electrodiagnostic test results often lead to changes in recommended treatment.

Evaluation of the scratch collapse test for the diagnosis of carpal tunnel syndrome

This prospective study measured and compared the diagnostic performance characteristics of various clinical signs and physical examination manoeuvres for carpal tunnel syndrome (CTS), including the scratch collapse test. Eighty-eight adult patients that were prescribed electrophysiological testing to diagnose CTS were enrolled in the study. Attending surgeons documented symptoms and results of standard clinical manoeuvres. The scratch collapse test had a sensitivity of 31%, which was significantly lower than the sensitivity of Phalen's test (67%), Durkan's test (77%), Tinel's test (43%), CTS-6 lax (88%), and CTS-6 stringent (54%). The scratch test had a specificity of 61%, which was significantly lower than the specificity of thenar atrophy (96%) and significantly higher than the specificity of Durkan's test (18%) and CTS-6 lax (13%). The sensitivity of the scratch collapse test was not superior to other clinical signs and physical examination manoeuvers for CTS, and the specificity of the scratch collapse test was superior to that of Durkan's test and CTS-6 lax. Further studies should seek to limit the influence of a patient's clinical presentation on scratch test performance and assess the scratch test's inter-rater reliability.

Symptoms, signs and nerve conduction velocities in patients with suspected carpal tunnel syndrome

BACKGROUND

To inform the clinical management of patients with suspected carpal tunnel syndrome (CTS) and case definition for CTS in epidemiological research, we explored the relation of symptoms and signs to sensory nerve conduction (SNC) measurements.

METHODS

Patients aged 20-64 years who were referred to a neurophysiology service for investigation of suspected CTS, completed a symptom questionnaire (including hand diagrams) and physical examination (including Tinel's and Phalen's tests). Differences in SNC velocity between the little and index finger were compared according to the anatomical distribution of symptoms in the hand and findings on physical examination.

RESULTS

Analysis was based on 1806 hands in 908 patients (response rate 73%). In hands with numbness or tingling but negative on both Tinel's and Phalen's tests, the mean difference in SNC velocities was no higher than in hands with no numbness or tingling. The largest differences in SNC velocities occurred in hands with extensive numbness or tingling in the median nerve sensory distribution and both Tinel's and Phalen's tests positive (mean 13.8, 95% confidence interval (CI) 12.6-15.0 m/s). Hand pain and thumb weakness were unrelated to SNC velocity.

CONCLUSIONS

Our findings suggest that in the absence of other objective evidence of median nerve dysfunction, there is little value in referring patients of working age with suspected CTS for nerve conduction studies if they are negative on both Tinel's and Phalen's tests. Alternative case definitions for CTS in epidemiological research are proposed according to the extent of diagnostic information available and the relative importance of sensitivity and specificity.

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.

Correspondence between clinical presentation and electrophysiological testing for potential carpal tunnel syndrome

The diagnosis of carpal tunnel syndrome (CTS) is often applied in the absence of objectively verifiable pathophysiology (i.e. electrophysiologically normal carpal tunnel syndrome). The primary purpose of this study was to determine whether depressive symptoms, heightened illness concern, and pain catastrophizing are associated with an absence of electrophysiological abnormalities. The secondary purpose was to examine the correspondence between the Levine scale, the CTS-6, and electrophysiological abnormalities. Ninety-eight participants completed validated questionnaires assessing psychosocial factors at the initial visit, and surgeons recorded clinical data and their confidence that the diagnosis was carpal tunnel syndrome. Symptoms and signs that are characteristic of carpal tunnel syndrome (e.g. the CTS-6 and Levine scale) significantly, but incompletely coincided with electrophysiological testing. Psychological factors did not help distinguish patients with normal and abnormal objective testing and it remains unclear if symptoms that do not coincide with abnormal tests represent very mild, immeasurable median nerve dysfunction or a different illness altogether. Future studies should address whether outcomes are superior and resource utilization is optimized when surgery is offered based on symptoms and signs (e.g. the CTS-6) or when surgery is offered on the basis of measurable pathophysiology.

Compression and entrapment neuropathies

Peripheral nerve entrapments are frequent. They usually appear in anatomical tunnels such as the carpal tunnel. Nerve compressions may be due to external pressure such as the fibular nerve at the fibular head. Malignant or benign tumors may also damage the nerve. For each nerve from the upper and lower limbs, detailed clinical, electrophysiological, imaging, and therapeutic aspects are described. In the upper limbs, carpal tunnel syndrome and ulnar neuropathy at the elbow are the most frequent manifestations; the radial nerve is less frequently involved. Other nerves may occasionally be damaged and these are described also. In the lower limbs, the fibular nerve is most frequently involved, usually at the fibular head by external compression. Other nerves may also be involved and are therefore described. The clinical and electrophysiological examination are very important for the diagnosis, but imaging is also of great use. Treatments available for each nerve disease are discussed.

Diagnostic performance tests for suspected scaphoid fractures differ with conventional and latent class analysis

BACKGROUND

Evaluation of the diagnostic performance characteristics of radiographic tests for diagnosing a true fracture among suspected scaphoid fractures is hindered by the lack of a consensus reference standard. Latent class analysis is a statistical method that takes advantage of unobserved, or latent, classes in the data that can be used to determine diagnostic performance characteristics when there is no consensus reference (gold) standard.

PURPOSES

We therefore compared the diagnostic performance characteristics of MRI, CT, bone scintigraphy, and physical examination to identify true fractures among suspected scaphoid fractures.

PATIENTS AND METHODS

We used data from two studies, one that prospectively studied 34 patients who had MRI and CT of the wrist, and a second that studied 78 patients who had MRI, bone scintigraphy, and structured physical examination. We compared the diagnostic performance characteristics calculated by latent class analysis with those calculated using formulas based on a reference standard.

RESULTS

In the first cohort, the calculated sensitivity and specificity with latent class analysis were different than those with traditional reference standard-based calculations for the CT in the scaphoid planes (sensitivity, 0.78 versus 0.67; specificity, 1.0 versus 0.96) and the MRI (sensitivity, 0.80 versus 0.67; specificity, 0.93 versus 0.89). In the second cohort, the greatest differences were in the sensitivity of MRI (0.84 versus 0.75) and the sensitivities of physical examination maneuvers (range, 0.63-0.73 versus 1.0).

CONCLUSIONS

The diagnostic performance characteristics calculated using latent class analysis may differ from those calculated according to formulas based on a reference standard. We believe latent class analysis merits further study as an option for assessing diagnostic performance characteristics for orthopaedic conditions when there is no consensus reference standard.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Assessment of the suspected fracture of the scaphoid

A suspected fracture of the scaphoid remains difficult to manage despite advances in knowledge and imaging methods. Immobilisation and restriction of activities in a young and active patient must be balanced against the risks of nonunion associated with an undiagnosed and undertreated fracture of the scaphoid.

The assessment of diagnostic tests for a suspected fracture of the scaphoid must take into account two important factors. First, the prevalence of true fractures among suspected fractures is low, which greatly reduces the probability that a positive test will correspond with a true fracture, as false positives are nearly as common as true positives. This situation is accounted for by Bayesian statistics. Secondly, there is no agreed reference standard for a true fracture, which necessitates the need for an alternative method of calculating diagnostic performance characteristics, based upon a statistical method which identifies clinical factors tending to associate (latent classes) in patients with a high probability of fracture.

The most successful diagnostic test to date is MRI, but in low-prevalence situations the positive predictive value of MRI is only 88%, and new data have documented the potential for false positive scans. The best strategy for improving the diagnosis of true fractures among suspected fractures of the scaphoid may well be to develop a clinical prediction rule incorporating a set of demographic and clinical factors which together increase the pre-test probability of a fracture of the scaphoid, in addition to developing increasingly sophisticated radiological tests.

Avaliação da sensibilidade cutânea em pacientes com síndrome do túnel do carpo relacionada à hemodiálise

OBJETIVO: Descrever a utilização do PSSD (Pressure specified sensory device) para a realização do diagnóstico de Síndrome do Túnel do Carpo. MÉTODOS: O PSSD consiste de aparelho que incorpora um transdutor de pressão com duas extremidades rombas e com regulagem de distância entre elas, acoplado a um computador capaz de determinar os limiares cutâneos de pressão. Para tanto, os pacientes foram divididos em três grupos: Grupo 1- grupo controle, pacientes sem neuropatia no membro superior ou insuficiência renal. Grupo 2- pacientes com síndrome do túnel do carpo relacionada à hemodiálise. Grupo 3 - pacientes com síndrome do túnel do carpo sem insuficiência renal. RESULTADOS: Os resultados demonstraram haver um maior benefício do uso do PSSD para o diagnóstico da síndrome para os pacientes do grupo dois em dois dos quatro parâmetros avaliados quando comparados com os pacientes do grupo 3. CONCLUSÃO: O PSSD é útil para o diagnóstico da síndrome do túnel do carpo em pacientes hemodialíticos. Nível de Evidência II. Estudos diagnósticos.

Service development and evaluation of a new carpal tunnel syndrome education class

Introduction

A carpal tunnel syndrome (CTS) education class was developed to enhance both patient care and the treatment pathway. In order to determine the efficiency and efficacy of the management of patients with CTS within a class setting, the results were assessed and reviewed over a one-year period.

Methods

Patients referred to Guys and St Thomas' Hand Therapy Department over a one-year period with CTS were provided with an appointment for the CTS class. All attendees completed an initial assessment form and a 1:1 assessment by a physiotherapist. A computer-based presentation was delivered within the class and patients were provided with prefabricated wrist splints in a neutral position and an education leaflet. Eighty-nine patients were followed up by a telephone call at six weeks and completed a telephone outcome form. A discharge letter was completed and sent to the referrer advising of the patients' outcome with further treatment recommendations if appropriate.

Results

At six-week telephone follow-up, 42 (47%) patients required no further treatment, 37 (42%) patients were recommended for further investigation, and 10 (11%) patients either had or planned to have carpal tunnel decompression.

Discussion

The new CTS class provides an efficient and effective treatment pathway for patients with CTS. It enables a comprehensive assessment and treatment application within the same session and aids early identification of other pathologies that may require intervention or appropriate onward referral.

When is the Phalen's test of diagnostic value: an electrophysiologic analysis?

The authors performed nerve conduction studies on 54 hands in patients referred with the clinical diagnosis of carpal tunnel syndrome. The authors studied the motor and sensory latencies of the median and ulnar nerves and compared them with each other. The authors divided the results into hands with no, mild, moderate, or severe carpal tunnel syndrome. The authors correlated these results with the presences or absence of the Phalen's sign. The authors concluded that the Phalen's sign is present mostly in the moderate to severe median nerve entrapment, but still can sometimes be present as a false positivity in normal hands.

Scratch collapse test for evaluation of carpal and cubital tunnel syndrome

PURPOSE

The purpose of this study was to evaluate the clinical usefulness of a new test, the scratch collapse test, for the diagnosis of carpal tunnel syndrome and cubital tunnel syndrome.

METHODS

The scratch collapse test was prospectively compared with Tinel's sign and flexion/nerve compression in 169 patients and 109 controls. One hundred nineteen patients were diagnosed with carpal tunnel syndrome and 70 patients were diagnosed with cubital tunnel syndrome based on history, examination, and positive electrodiagnostic test. For the new test, the patient resisted bilateral shoulder external rotation with elbows flexed. The area of suspected nerve compression was lightly "scratched," and then resisted shoulder external rotation was immediately repeated. Momentary loss of shoulder external rotation resistance on the affected side was considered a positive test. The sensitivity, specificity, and predictive values were calculated.

RESULTS

For carpal tunnel syndrome, sensitivities were 64%, 32%, and 44% for the scratch collapse test, Tinel's test, and wrist flexion/compression test, respectively. For cubital tunnel syndrome, sensitivities were 69%, 54%, and 46% for the scratch collapse test, Tinel test, and elbow flexion/compression test, respectively. The scratch collapse test had the highest negative predictive value (73%) for carpal tunnel syndrome. Tinel's test had the highest negative predictive value (98%) for cubital tunnel syndrome. Specificity and positive predictive values were high for all of the tests.

CONCLUSIONS

The scratch collapse test had significantly higher sensitivity than Tinel's test and the flexion/nerve compression test for carpal tunnel and cubital tunnel syndromes. Accuracy for this test was 82% for carpal tunnel syndrome and 89% for cubital tunnel syndrome. This novel test provides a useful addition to existing clinical maneuvers in the diagnosis of these common nerve compression syndromes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

The pneumatic compression test and modified pneumatic compression test in the diagnosis of carpal tunnel syndrome

There are no precise criteria for the diagnosis of carpal tunnel syndrome (CTS): the history is useful but the value of the various provocative tests is questionable. The purpose of this study was to examine the diagnostic value of a new provocative test, the 'modified pneumatic compression test' in CTS. The study group consisted of 37 patients with 50 symptomatic CTS hands. A control group of 50 healthy volunteers was recruited. The diagnosis was based on a combination of the history, the clinical findings on examination and electrophysiological criteria. Sensitivity for the pneumatic compression and the modified pneumatic compression tests were 68% and 84%, respectively. Specificities for these tests were 97% and 95%, respectively. The modified pneumatic compression test demonstrated high sensitivity and specificity for CTS. This test facilitated the diagnosis and was easy to use. It may reduce referrals for neurophysiology testing, and so reduce costs.

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.

Repetitive strain injury

Repetitive strain injury remains a controversial topic. The term repetitive strain injury includes specific disorders such as carpal tunnel syndrome, cubital tunnel syndrome, Guyon canal syndrome, lateral epicondylitis, and tendonitis of the wrist or hand. The diagnosis is usually made on the basis of history and clinical examination. Large high-quality studies using newer imaging techniques, such as MRI and ultrasonography are few. Consequently, the role of such imaging in diagnosis of upper limb disorders remains unclear. In many cases, no specific diagnosis can be established and complaints are labelled as non-specific. Little is known about the effectiveness of treatment options for upper limb disorders. Strong evidence for any intervention is scarce and the effect, if any, is mainly short-term pain relief. Exercise is beneficial for non-specific upper limb disorders. Immobilising hand braces and open carpal tunnel surgery release are beneficial for carpal tunnel syndrome, and topical and oral non-steroidal anti-inflammatory drugs, and corticosteroid injections are helpful for lateral epicondylitis. Exercise is probably beneficial for neck pain, as are corticosteroid injections and exercise for shoulder pain. Although upper limb disorders occur frequently in the working population, most trials have not exclusively included a working population or assessed effects on work-related outcomes. Further high-quality trials should aim to include sufficient sample sizes, working populations, and work-related outcomes.