The Association Between Electrodiagnostic Severity and Treatment Recommendations for Carpal Tunnel Syndrome

Development and validation of a clinical model for predicting the severity of carpal tunnel syndrome

OBJECTIVES

To develop a clinical instrument to assess carpal tunnel syndrome (CTS) severity before electrodiagnostic testing.

METHODS

Data from 1037 patients with CTS (39.1% male) were included. The mean (SD) age was 58.0 (10.8) years. The severity of CTS was based on electrodiagnostic findings.

RESULTS

We devised a composite index incorporating a pain numeric rating scale (NRS) rated from 0 (no pain at all) to 10 (the worst pain ever possible), thenar muscle weakness or atrophy (TW), cross-sectional area (CSA) of the median nerve (mm2), and nocturnal pain (NP). The index was calculated as [scale(NRS)+scale(CSA)+NP+TW]/4, where NP and TW are binary features (0 or 1). The accuracy and area under the curve of the index were 0.85 and 0.71, respectively (Cohen's Kappa = 0.51, McNemar's test P = 0.249). The index increased pretest probabilities by 1.6, 1.8, and 3.3 times with positive likelihood ratios of 3.3, 2.5, and 13.5, and false-positive rates of 26.6, 17.6, and 4.8% for mild, moderate, and severe CTS, respectively. The index thresholds for mild, moderate, and severe CTS were <0.8, ≥0.8 to <1.1, and ≥1.1, respectively.

CONCLUSION

Using a composite index, patients with CTS can be categorized for the severity of the syndrome.

Electrodiagnostic severity does not predict short- to midterm outcomes of cubital tunnel release surgery

HYPOTHESIS

This study aimed to explore the prognostic value of electrodiagnostic studies (EDS) to clarify their utility in clinical practice prior to cubital tunnel release surgery and to identify patient factors associated with patient-reported functional improvement after surgery. Our hypothesis was that patients with severe preoperative findings on EDS will tend to experience less functional improvement after surgery given the extent of ulnar nerve compressive injury.

METHODS

Patients with cubital tunnel syndrome and preoperative electrodiagnostic data treated from 2012 to 2022 with cubital tunnel release were assessed regarding demographic information, preoperative physical examination findings, EDS findings, postoperative complications, and patient-reported outcomes. Short- to midterm quick Disabilities of the Arm, Shoulder, and Hand questionnaire (qDASH) scores were collected for all patients for further evaluation of preoperative EDS data. Patients were grouped into those who had met the minimal clinically important difference (MCID) in delta qDASH at short- to midterm follow-up and those who did not. EDS data included sensory nerve onset latency, peak latency, amplitude, conduction velocity, as well as motor nerve latency, velocity, and amplitude. Electromyographic (EMG) studies were also reviewed, which included data pertaining to fibrillations, presence of abnormal fasciculation, positive sharp waves, variation in insertional activity, motor unit activity, duration of activity, and presence of increasing polymorphisms.

RESULTS

Of the 257 patients included, 160 (62.0%) were found to meet the MCID for short- to midterm qDASH scores. There were no significant differences between patients who did or did not meet the MCID regarding baseline demographics, comorbidities, preoperative examination findings, and operative technique. Patients who met MCID tended to have lower complication (3.80% vs. 7.20%, P = .248) and revision (0.60% vs. 4.10%, P = .069) rates, but these findings were not statistically significant. The cubital tunnel severity as determined by the EDS was similar between cohorts (14.1% vs. 14.3%, P = .498). Analysis of EMG testing showed there were no significant differences in preoperative, short- to midterm qDASH, or delta short- to midterm qDASH scores for patients with or without abnormal EMG findings. Multivariate regression suggested that only age (P = .003) was associated with larger delta qDASH scores.

CONCLUSION

Patient-reported preoperative disease severity may predict the expected postoperative change in ulnar nerve functional improvement, and EDS may not have prognostic value for patients undergoing cubital tunnel decompression. Therefore, physicians may suggest surgical treatment without positive EDS findings and still expect postoperative improvement in functional outcomes.

Carpal Tunnel Syndrome Electrodiagnostic Severity is Not Associated with PROMIS Upper Extremity, PROMIS Pain Interference and PROMIS Pain Intensity

Background: The primary objective of this study was to determine the association between preoperative electrodiagnostic study (EDS) parameters and Patient-Reported Outcomes Measurement Information System (PROMIS) instruments in patients with EDS-confirmed carpal tunnel syndrome (CTS). Methods: A retrospective study of 45 patients with EDS-confirmed CTS was conducted. Patients completed the PROMIS Upper Extremity, PROMIS Pain Interference and PROMIS Pain Intensity. Explanatory variables included EDS disease severity (mild, moderate and severe), sensory peak latency, sensory amplitude, motor latency, motor amplitude, the presence of nonrecordable sensory latency and the presence of nonrecordable sensory amplitude. Explanatory variables also included patient-related factors, such as age, sex and diabetes mellitus. Associations between variables were assessed using simple linear regression, analysis of variance (ANOVA) and Student's t-test. Results: In our cohort, the EDS severity was mild in 38%, moderate in 42% and severe in 20% of patients. The mean PROMIS Upper Extremity score was 44.4, the mean PROMIS Pain Interference score was 53.5 and the mean PROMIS Pain Intensity score was 49.9. Bivariate analysis demonstrated no association between EDS severity overall or any EDS parameter individually and PROMIS Upper Extremity, PROMIS Pain Interference and PROMIS Pain Intensity. Diabetes mellitus was associated with poorer PROMIS Upper Extremity scores. Conclusions: EDS severity is not associated with PROMIS Upper Extremity, PROMIS Pain Interference and PROMIS Pain Intensity. Carpal tunnel release is commonly indicated for pain and dysfunction, but validated measures of pain and dysfunction do not correlate with EDS severity. Level of Evidence: Level III (Diagnostic).

Influence of Electrodiagnostic Studies on Surgery for Carpal Tunnel Syndrome: A Retrospective Analysis of Data from a Single Urban Institution

Background: This study aimed to clarify the influence of preoperative electrodiagnostic (EDX) utilisation and its severity on surgically treated patients with carpal tunnel syndrome (CTS). Methods: This retrospective study analysed the data of patients who underwent CTS surgery at our facility from 2012 to 2022. Data regarding age, sex, affected side, diabetes mellitus, rheumatoid arthritis, haemodialysis and insurance type were collected, along with the following clinical information: utilisation of EDX, steroid injection, number of items of preoperative physical examination and history taking, intervals between symptom onset and the initial visit and between the initial visit and surgery, type of surgical procedure and surgery categorisation (primary or revision). EDX data (EDX severity, interval between EDX and surgery and concomitant nerve lesions) were also investigated. Univariate and multivariate analyses were conducted to assess the influence of EDX utilisation and severity on clinical parameters. Results: Of the 343 hands enrolled in our study, 304 (89%) underwent preoperative EDX assessment. EDX severity was classified as normal, mild, moderate or severe in 6 (2%), 18 (6%), 102 (34%) and 178 hands (58%), respectively. After the univariate and multivariable analyses, more items of preoperative physical examination and history taking were associated with non-EDX utilisation, whereas younger age, female sex and steroid injection were associated with milder EDX. Conclusions: Increased number of items of preoperative physical examination and history taking or steroid injection were independently associated with non-EDX utilisation or milder EDX, respectively, suggesting that when thorough clinical evaluation is conducted, hand surgeons may be less likely to request for EDX before surgery. Moreover, their treatment recommendation may be influenced by EDX severity. Level of Evidence: Level III (Diagnostic).

Vasculitis presenting as carpal tunnel syndrome: a case report

BACKGROUND

Carpal tunnel syndrome is the most common focal mononeuropathy which presents with pain in the wrist and hand, paresthesia, loss of sensation in the distribution of the median nerve, and in more severe cases, weakness and atrophy of the thenar muscles. Meanwhile, carpal tunnel syndrome can present as an initial manifestation of underlying systemic vasculitis disorder and result in severe physical disabilities.

CASE PRESENTATION

A 27-year-old Iranian man was referred to our electrodiagnosis center with a clinical diagnosis of carpal tunnel syndrome in April 2020. Surgical intervention had been taken into account for him because of unsuccessful conservative therapies. On admission, thenar eminence was reduced. Electrodiagnostic findings were not compatible with median nerve entrapment at the wrist. All sensory modalities in the distribution of the right median nerve were decreased. Additionally, a mild increase in erythrocyte sedimentation rate was noted in laboratory tests. Because of the high vasculitis suspicion, we recommended the nerve biopsy and/or starting a high-dose corticosteroid. However, the surgery release was performed. After 6 months, the patient was referred for progressive weakness and numbness in the upper and lower limbs. After documentation of vasculitis neuropathy by biopsy, a diagnosis of non-systemic vasculitic neuropathy was confirmed. A rehabilitation program started immediately. Rehabilitation led to gradual improvement and recovery of function and muscle strength, and no complications remained, except mild leg paralysis.

CONCLUSIONS

Physicians should be suspicious of the median nerve vasculitis mononeuropathy in a patient with carpal tunnel syndrome-like symptoms. Median nerve vasculitis mononeuropathy as an initial presenting feature of vasculitis neuropathy can further result in severe physical impairments and disabilities.

The Preoperative Cost of Carpal Tunnel Syndrome

PURPOSE

Carpal tunnel syndrome is a common condition, with well-defined diagnostic and treatment guidelines. Despite these guidelines, continued variation in care exists, with providers variably using diagnostic tests and nonsurgical treatment modalities prior to surgery. The purpose of this study was to evaluate the variation and cost associated with the diagnosis and nonsurgical treatment of patients prior to undergoing carpal tunnel release.

METHODS

We queried the Truven MarketScan database to identify patients who underwent carpal tunnel release from 2010 to 2017. Patients were identified using common current procedural terminology codes and included if they were enrolled in the database for a minimum of 12 months prior to surgery to allow all preoperative data to be captured. All associated current procedural terminology codes during the 1-year preoperative period were refined to codes related to median neuropathy and categorized as office visits, diagnostic imaging (x-ray, ultrasound, and magnetic resonance imaging), electrodiagnostic testing, injections, occupational or physical therapy, durable medical equipment, and preoperative laboratory tests.

RESULTS

In total, 378,381 patients were included in the study. A per-patient average cost of $858.74 was spent on preoperative workup and nonsurgical treatment. Electrodiagnostic testing represented 44.6% of the cost, and office visits represented 31.9%. Regarding nonsurgical treatment, 16.1% of the patients received an injection during the 1-year preoperative period, 26.8% received a medical brace, and 6.6% used physical therapy. When analyzed based on age group, the per-patient average cost for patients aged 70 years or older was significantly less than those younger than 70 years ($723.92 vs $878.76).

CONCLUSIONS

Despite robust clinical practice guidelines and high volumes, significant variation in presurgical care exists. These data are useful to begin to critically analyze the causes of variation in the diagnosis and treatment of carpal tunnel syndrome and move toward a more effective, efficient, and informed treatment strategy.

TYPE OF STUDY/LEVEL OF EVIDENCE

Economic/decision analysis II.

Effectiveness of ultrasound-guided local steroid injection to the wrist for the treatment of carpal tunnel syndrome: Is it worth it?

Background

Carpal tunnel syndrome (CTS) is caused by compression of the median nerve at the wrist level and the most frequent entrapment neuropathy in the upper limb. It can be treated with surgical or non-surgical methods. When nonsurgical treatment is indicated, a local corticosteroid injection into the carpal tunnel can be used to reduce pain and tingling sensation. To assess the clinical outcomes and effectiveness of patient satisfaction following ultrasound-guided steroid injection for the treatment of carpal tunnel syndrome.

Results

The study comprises 44 female (73%) and 16 (27%) male patients, with a mean age of 57 (27–84) years. Thirty-one patients were left-handed and 29 right-handed. Twenty-six (43%) injections were performed on the right side, 8 (13%) on the left, and 26 were bilateral. Fifty-six hands of thirty-seven (70%) patients reported significant improvement symptoms, five (8%) had temporary improvement with recurrence, seventeen patients (28%) failed to improve, and one patient’s symptoms have resolved before intervention. Among temporary responders and nonresponders, two were referred to the neurologist for further evaluation. Out of twenty patients, fourteen patients (23%) had surgical decompression of carpal tunnel with complete resolution of symptoms, four patients had opted for repeat injections, and two patients refused any further intervention.

Conclusions

The use of ultrasound-guided injection for the treatment of mild to moderate carpal tunnel syndrome is a practical procedure before offering surgical treatment. It is also appropriate for the patient with significant medical problems or not willing to undergo surgical intervention. Its ultrasound guide reduces injection-related complications, improves patient satisfaction, is cost-effective, and improves patient compliance.

A Systematic Review of the Outcomes of Carpal Ligament Release in Severe Carpal Tunnel Syndrome

PURPOSE

Indications for surgical treatment of severe carpal tunnel syndrome (CTS) are controversial. The aim of this study was to review the outcomes reported in the literature of carpal tunnel release in patients with severe CTS.

METHODS

A systematic review of the outcomes of carpal tunnel release in patients with severe CTS was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Outcome measures included change in symptoms, sensation (2-point discrimination, light touch), thenar atrophy, strength (power and pinch grip), electrophysiology, median nerve morphology, and patient-reported outcome measures. Outcomes are reported by ranges of the percentage of patients/hands improved in the included studies.

RESULTS

Thirty-eight papers were selected, representing 2,531 patients and 2,712 hands. Demographic information on age and sex were available for a total of 1,542 patients. Mean age ranged from 49.8 to 83 years and 72% were female. All studies that assessed patient-reported outcome measures before and after surgery reported significant improvements. Complete resolution of paresthesia occurred in 55%-98% of hands across different studies. Resolution of numbness occurred in between 39% and 94% of hands. Pain completely resolved in 64%-100% and weakness in 60%-75% of hands. Two-point discrimination and light touch improved postoperatively. Power grip, key, tripod, index-thumb pulp pinch, and thumb opposition increased. Motor and sensory amplitudes, distal motor latencies, and sensory conduction velocities improved. Patient-reported outcomes indicated symptomatic improvement and reduced disability.

CONCLUSIONS

Symptomatic improvement following carpal tunnel release in patients with severe CTS can occur. Patients should be counseled about the unpredictability of the outcomes and factors that might affect outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

The top 50 most cited articles in carpal tunnel syndrome research: A bibliometrics study

BACKGROUND

Citation analysis was applied to identify the influential studies in the specific field. More and more literature related to carpal tunnel syndrome (CTS) have been published in recent years. To our knowledge, no one has performed a citation analysis of CTS. Thus, our study identified the top 50 influential articles pertaining to CTS and conduct an analysis of their characteristics.

METHODS

The Web of Science database was used to identify all the articles from 1900 to 2020. We obtained the top 50 articles ranked by citation times, and articles were included and excluded based on the relevance to CTS. Also, we collected the information about journal name, level of evidence, source country and institution, and research type for further analysis.

RESULTS

The top 50 articles were published between 1959 and 2012. The number of citations ranged from 151 to 1083. The citation density was between 3.23 and 40.27 per year. Muscle Nerve published most articles in CTS research, followed by Journal of Bone and Joint Surgery American Volume. The USA was the leading country, and all the top 5 institutions were from the USA. Katz JN with the highest h-index published most articles. Level III was the most common evidence level.

CONCLUSIONS

We identified the top 50 cited articles related to CTS. These influential articles might provide researchers with a comprehensive list of the major contribution related to CTS research.

Meta-analysis of the normal diffusion tensor imaging values of the median nerve and how they change in carpal tunnel syndrome

Carpal tunnel syndrome (CTS) leads to distortion of axonal architecture, demyelination and fibrosis within the median nerve. Diffusion tensor imaging (DTI) characterises tissue microstructure and generates reproducible proxy measures of nerve 'health' which are sensitive to myelination, axon diameter, fiber density and organisation. This meta-analysis summarises the normal DTI values of the median nerve, and how they change in CTS. This systematic review included studies reporting DTI of the median nerve at the level of the wrist in adults. The primary outcome was to determine the normal fractional anisotropy (FA) and mean diffusivity (MD) of the median nerve. Secondarily, we show how the FA and MD differ between asymptomatic adults and patients with CTS, and how these differences are independent of the acquisition methods. We included 32 studies of 2643 wrists, belonging to 1575 asymptomatic adults and 1068 patients with CTS. The normal FA was 0.58 (95% CI 0.56, 0.59) and the normal MD was 1.138 × 10^-3 mm²/s (95% CI 1.101, 1.174). Patients with CTS had a significantly lower FA than controls (mean difference 0.12 [95% CI 0.09, 0.16]). Similarly, the median nerve of patients with CTS had a significantly higher mean diffusivity (mean difference 0.16 × 10^-3 mm²/s [95% CI 0.05, 0.27]). The differences were independent of experimental factors. We provide summary estimates of the normal FA and MD of the median nerve in asymptomatic adults. Furthermore, we show that diffusion throughout the length of the median nerve becomes more isotropic in patients with CTS.