AAEM minimonograph #26: the electrodiagnosis of carpal tunnel syndrome. American Association of Electrodiagnostic Medicine

Application of radiomics model based on ultrasound image features in the prediction of carpal tunnel syndrome severity

OBJECTIVE

The aim of our study is to develop and validate a radiomics model based on ultrasound image features for predicting carpal tunnel syndrome (CTS) severity.

METHODS

This retrospective study included 237 CTS hands (106 for mild symptom, 68 for moderate symptom and 63 for severe symptom). There were no statistically significant differences among the three groups in terms of age, gender, race, etc. The data set was randomly divided into a training set and a test set in a ratio of 7:3. Firstly, a senior musculoskeletal ultrasound expert measures the cross-sectional area of median nerve (MN) at the scaphoid-pisiform level. Subsequently, a recursive feature elimination (RFE) method was used to identify the most discriminative radiomic features of each MN at the entrance of the carpal tunnel. Eventually, a random forest model was employed to classify the selected features for prediction. To evaluate the performance of the model, the confusion matrix, receiver operating characteristic (ROC) curves, and F1 values were calculated and plotted correspondingly.

RESULTS

The prediction capability of the radiomics model was significantly better than that of ultrasound measurements when 10 robust features were selected. The training set performed perfect classification with 100% accuracy for all participants, while the testing set performed accurate classification of severity for 76.39% of participants with F1 values of 80.00, 63.40, and 84.80 for predicting mild, moderate, and severe CTS, respectively. Comparably, the F1 values for mild, moderate, and severe CTS predicted based on the MN cross-sectional area were 76.46, 57.78, and 64.00, respectively..

CONCLUSION

This radiomics model based on ultrasound images has certain value in distinguishing the severity of CTS, and was slightly superior to using only MN cross-sectional area for judgment. Although its diagnostic efficacy was still inferior to that of neuroelectrophysiology. However, this method was non-invasive and did not require additional costs, and could provide additional information for clinical physicians to develop diagnosis and treatment plans.

Is Ultrasonography a Reliable Approach for the Evaluation of Carpal Tunnel Syndrome in Patients With Mucopolysaccharidosis?

BACKGROUND

One of the most common causes of carpal tunnel syndrome (CTS) in childhood is mucopolysaccharidosis (MPS). While ultrasonography (US) can aid in the diagnosis of CTS in adult patients, there is limited experience of this in the pediatric group. We aimed to investigate the results of wrist ultrasonography, which may be a candidate alternative to electrophysiological examination.

METHODS

The participants were evaluated for symptoms, physical examination findings, electrophysiological tests and grayscale US. CTS was diagnosed in accordance with the American Academy of Orthopedic Surgeons Management of Carpal Tunnel Syndrome: Evidence-Based Clinical Practice Guideline.

RESULTS

Included in the study were 27 MPS patients aged 4.5-32 years and 30 healthy control subjects aged 4.3-26 years. Of the 54 wrists in the MPS group, 30 were diagnosed with CTS. The median cross-sectional area (CSA) at the proximal carpal tunnel, the CSA at the forearm, and the wrist-forearm ratio (WFR) were higher in the wrists of the MPS with CTS group than in those without CTS and the healthy control subjects. The WFR cutoff of ≥1.35, 56.6% (95% CI: 437.4-74.5) sensitivity, and 89.8% (95% CI: 81.0-95.5) specificity were consistent with a diagnosis of CTS (receiver operating characteristics analysis, area under the curve = 0.775, 95% CI: 0.673-0.877).

CONCLUSION

Although the US provides results with unsatisfactory specificity and sensitivity, it is a candidate for further investigation for the diagnosis of CTS because it is an innovative, noninvasive, and more accessible method. WFR value may produce more meaningful results than wrist or forearm nerve area measurements.

Carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is the most common nerve entrapment disorder worldwide. The epidemiology and risk factors, including family burden, for developing CTS are multi-factorial. Despite much research, its intricate pathophysiological mechanism(s) are not fully understood. An underlying subclinical neuropathy may indicate an increased susceptibility to developing CTS. Although surgery is often performed for CTS, clear international guidelines to indicate when to perform non-surgical or surgical treatment, based on stage and severity of CTS, remain to be elucidated. Neurophysiological examination, using electrophysiology or ultrasonography, performed in certain circumstances, should correlate with the history and findings in clinical examination of the person with CTS. History and clinical examination are particularly relevant globally owing to lack of other equipment. Various instruments are used to assess CTS and treatment outcomes as well as the effect of the disorder on quality of life. The surgical treatment options of CTS - open or endoscopic - offer an effective solution to mitigate functional impairments and pain. However, there are risks of post-operative persistent or recurrent symptoms, requiring meticulous diagnostic re-evaluation before any additional surgery. Health-care professionals should have increased awareness about CTS and all its implications. Future considerations of CTS include use of linked national registries to understand risk factors, explore possible screening methods, and evaluate diagnosis and treatment with a broader perspective beyond surgery, including psychological well-being.

The association between menopausal status and clinical outcomes of female patients with carpal tunnel release: a retrospective observational study

BACKGROUND

The relationship between menopausal status and clinical outcomes of female patients with carpal tunnel release (CTR) has been not clearly investigated. This study aimed to evaluate the clinical outcomes of CTR among women with different menopausal statuses.

METHODS

Two hundred-eighteen consecutive female patients with carpal tunnel syndrome (CTS) who underwent surgery at our hospital between May 2016 and May 2020 were included in this study. Based on whether subjects had undergone menopause before surgery, they were divided into three groups: the premenopausal group, the early postmenopausal group (less than 10 years since menopause) and the late postmenopausal group (more than 10 years since menopause). The clinical outcome was assessed before surgery and at six-month postoperative visits using the Boston Carpal Tunnel Questionnaire (BCTQ).

RESULTS

There were 86 patients in the premenopausal group, 70 patients in the early postmenopausal group and 62 patients in the late postmenopausal group. All the groups showed significant improvements in their Symptom Severity Scale (SSS) and Functional Status Scale (FSS) compared with preoperative scores. Although, there was a significant difference between the groups based and post-surgical SSS and FSS (p < 0.05). Patients in the postmenopausal group had less improvement in SSS and FSS in comparison with those in the other groups (p < 0.05).

CONCLUSIONS

Our results showed that all the groups had significant improvement in their SSS and FSS. However, the clinical outcomes were poorer in late postmenopausal patients than in premenopausal or early postmenopausal patients. These findings can be used in pre-operative counseling and interpretation of outcomes in women with CTR.

Mapping Neurophysiological Patterns in Carpal Tunnel Syndrome: Correlations With Tinel's and Phalen's Signs

Background This study aimed to observe the neurophysiological severity grading of carpel tunnel syndrome (CTS) using nerve conduction studies (NCSs) and the correlation between Tinel's and Phalen's signs. Methodology In this cross-sectional study, 240 patients of CTS were enrolled. NCSs were conducted in 480 hands. Various variables such as distal latency, amplitude, and nerve conduction velocity in both sensory and motor median nerves were recorded. The provocative tests capable of reproducing patients' symptoms such as Phalen's test and Tinel's test were performed on all 480 hands studied. Results Neurophysiological variables were affected in 449 out of 480 hands. Tinel's sign was observed in 59% of cases (265 hands) while Phalen's sign was positive in 37.2% (167 hands) of cases. Severity grading of CTS based on neurophysiological variables resulted in Grade I (mild) in 202 hands, Grade II (mild to moderate) in 56 hands, Grade III (moderate) in 39 hands, and Grade IV (severe) in 152 hands. Provocative tests (Tinel's and Phalen's) used for the diagnosis of CTS were positive in 68 hands (36.66%) and 26 hands (12.8%), respectively, in mild Grade I. However, as the CTS severity grade increased, the provocative test success rate also increased simultaneously. In severe Grade IV CTS, Tinel's and Phalen's tests were positive in 134 (88.1%) hands and 94 (61.8%) hands, respectively. Conclusions This study underscores the unreliability of Tinel's and Phalen's signs as screening methods for CTS severity. With moderate sensitivity and specificity, NCSs are deemed essential for confirming CTS diagnosis and assessing severity, especially in mild cases that might be mistakenly perceived as normal hands by consultants.

Diagnostic efficacy of high-frequency Grey-scale ultrasonography and Sono-elastography in grading the severity of carpal tunnel syndrome in comparison to nerve conduction studies

OBJECTIVES

To correlate the cross-sectional area (CSA) and elasticity of the median nerve (MN) measured at carpal tunnel inlet between healthy controls and various degrees of carpal tunnel syndrome (CTS) graded as per nerve conduction studies (NCS).

MATERIALS AND METHODS

A total of 53 patients (with 81 wrists) presenting with clinical symptoms characteristic of CTS, having their diagnosis confirmed and severity graded by NCS, and 48 healthy controls (with 96 wrists) were included in the study. All the study participants underwent wrist ultrasound which included initial Grey-scale USG followed by strain and shear wave elastography. The CSA and elasticity (in terms of strain ratio and shear modulus) of MN were measured at the carpal tunnel inlet. Statistical analysis was performed using the Mann-Whitney U test to compare between the two groups and for subgroup analysis of cases. The diagnostic performance of each variable was evaluated using the receiver operating characteristic curves.

RESULTS

The mean CSA was 9.20 ± 1.64, 11.48 ± 1.05, 14.83 ± 1.19 and 19.87 ± 2.68 mm2, the mean shear modulus was 17.93 ± 2.81, 23.59 ± 2.63, 32.99 ± 4.14 and 54.26 ± 9.24 kPa and the mean strain ratio was 5.26 ± 0.68, 5.56 ± 0.70, 7.03 ± 0.47 and 8.81 ± 0.94 in control, mild, moderate and severe grades of CTS, respectively (p < 0.001).

CONCLUSION

The combined utility of Grey-scale USG and Elastography may serve as a painless and cost-effective alternative to NCS in grading the severity of CTS.

The prevalence of carpal tunnel syndrome in patients with epilepsy

Objective

Carpal tunnel syndrome (CTS) is the most common type of entrapment neuropathy caused by compression of the median nerve in the carpal tunnel. Epilepsy is characterised by recurrent seizures caused by abnormal neuronal discharges in the brain.This study aimed to investigate whether there is a link between epilepsy and carpal tunnel and, if so, the underlying factors.

Materials and methods

Two hundred patients with epilepsy were included in this study. The patients' history of epilepsy, seizure type, and seizure frequency were assessed. The Tinel, Phalen, and Flick physical examination tests were performed on patients with complaints that matched those of median nerve neuropathy. Patients with epilepsy and clinically diagnosed carpal tunnel syndrome completed the Boston Carpal Tunnel Syndrome Questionnaire, and nerve conduction studies were performed. The relationship between seizure type and frequency in patients with carpal tunnel syndrome was compared.

Results

Compared to focal-aware motor-onset seizures, the risk of detecting carpal tunnel syndrome was 88.7 times higher in focal-onset bilateral tonic-clonic seizures. Patients with a seizure frequency of one per month or more had a 0.704 times lower risk of CTS than those with a frequency of one per week or more (p = 0.026).

Discussion

Patients with epilepsy, especially those experiencing frequent seizures or specific seizure types, may be more susceptible to repetitive wrist flexion-extension postures. Therefore, during clinical follow-up, it is important to inquire about the presence of carpal tunnel syndrome in patients with epilepsy.

A revised approach for electrodiagnosis-based severity classification in carpal tunnel syndrome

BACKGROUND

An electrodiagnostic evaluation is conducted to diagnose carpal tunnel syndrome (CTS) and evaluate its severity.

OBJECTIVE

This study proposes a revised approach for classifying the severity of electrophysiological findings for patients with CTS.

METHODS

This retrospective cross-sectional study included patients with CTS confirmed through electrodiagnostic evaluations. Based on the Stevens' classification, the patients were divided into three groups (mild/moderate/severe). A new intermediate group was defined to identify patients with normal motor nerve conduction studies and abnormal electromyographic results. CTS pain was evaluated using a numeric rate scale. Physical examinations and sonographic evaluation were performed to detect anatomical abnormalities.

RESULTS

Overall, 1,069 CTS hands of 850 CTS patients were included. The mean age was 57.9 ± 10.8 years, and 336 (39.5%) were men. There were 522 (48.8%) mild cases; 281 (26.3%) moderate cases; and 266 (24.9%) severe cases. In the severe group, 49 cases were reclassified into the intermediate group. The median cross-sectional area in the intermediate group significantly differed from that in the severe group. However, the pain score significantly differed from that of the moderate group.

CONCLUSION

The intermediate CTS group showed clinical features that were intermediate to those of the moderate and severe CTS groups.

Point of care ultrasound combined with CTS-6 to diagnose idiopathic carpal tunnel syndrome

BACKGROUND

This study aimed to demonstrate the effectiveness of our new diagnostic chart using point of care ultrasound combined with CTS-6 for diagnosing idiopathic carpal tunnel syndrome.

METHODS

We conducted a retrospective analysis of the data of patients who visited our department and received point of care ultrasound combined with CTS-6 from 2020 to 2023. Data regarding age, sex, initial and final diagnosis, cross-sectional area of the median nerve, CTS-6 score, and electrodiagnostic severity were obtained and statistically analyzed.

RESULTS

Of the 177 wrists included in our study, 138 (78 %) were diagnosed with carpal tunnel syndrome, while 39 (22 %) were not (non-carpal tunnel syndrome). With our diagnostic method, 127 wrists (72 %) were diagnosed initially with carpal tunnel syndrome, 23 wrists (13 %) with non-carpal tunnel syndrome, and the rest 27 wrists (15 %) as borderline. Our initial diagnoses of carpal tunnel syndrome and non-carpal tunnel syndrome were maintained in all cases except for two. Cross-sectional area, CTS-6 score, and electrodiagnostic severity showed a positive correlation. A post hoc analysis showed that the new scoring system (CTS-6 score + 2 × cross-sectional area) with a cutoff value of 31.25 points showed a sensitivity as high as 95 % and a specificity of 100 %.

CONCLUSIONS

Our findings suggest that most suspected idiopathic carpal tunnel syndrome cases can be diagnosed correctly using the diagnostic chart. Although additional tools, including electrodiagnostic studies, may be needed for borderline cases, the use of point of care ultrasound combined with CTS-6 may be a recommendable first-line confirmatory test because point of care ultrasound and CTS-6 could be complementary tools, and this chart may be especially beneficial for atypical or outlier cases.

LEVEL OF EVIDENCE

Diagnostic III.

Safety and Efficacy of Ultrasound-Guided Perineural Hydrodissection as a Minimally Invasive Treatment in Carpal Tunnel Syndrome: A Systematic Review

Ultrasound-guided perineural hydrodissection (HD) is a novel technique that has been found to be effective in providing mechanical release of perineural adhesions and decompression of the nerve, reducing inflammation and edema and restoring its physiological function. It has a significant impact on chronic neuropathic pain (20 ± 4 weeks with VAS < 5 or VAS diminished by 2 points after the procedure). Carpal tunnel syndrome (CTS) is a common entrapment mononeuropathy, and its distribution is typically innervated by the median nerve. Patients with mild or moderate CTS may benefit from nonsurgical treatments or conservative therapies. This review was conducted following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement guidelines. Four investigators assessed each title, abstract, and full-text article for eligibility, with disagreements being resolved by consensus with two experienced investigators. The qualitative assessment of the studies was carried out using the modified Oxford quality scoring system, also known as the modified Jadad score. Furthermore, risk of possible biases was assessed using the Cochrane collaboration tool. The results of this review suggest that US-guided HD is an innovative, effective, well-tolerated, and safe technique (11 out of 923 patients had collateral or side effects after the procedure). However, further studies comparing all drugs and with a larger sample population are required to determine the most effective substance.

Surgical versus non-surgical treatment for carpal tunnel syndrome

BACKGROUND

Carpal tunnel syndrome (CTS) is a compression neuropathy of the median nerve at the wrist. Surgery is considered when symptoms persist despite the use of non-surgical treatments. It is unclear whether surgery produces a better outcome than non-surgical therapy. This is an update of a Cochrane review published in 2008.

OBJECTIVES

To assess the evidence regarding the benefits and harms of carpal tunnel release compared with non-surgical treatment in the short (< 3 months) and long (> 3 months) term.

SEARCH METHODS

In this update, we included studies from the previous version of this review and searched the Cochrane Neuromuscular Specialised Register, CENTRAL, Embase, MEDLINE, ClinicalTrials.gov and WHO ICTRP until 18 November 2022. We also checked the reference lists of included studies and relevant systematic reviews for studies.

SELECTION CRITERIA

We included randomised controlled trials comparing any surgical technique with any non-surgical therapies for CTS.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

The 14 included studies randomised 1231 participants (1293 wrists). Eighty-four per cent of participants were women. The mean age ranged from 32 to 53 years, and the mean duration of symptoms from 31 weeks to 3.5 years. Trial sizes varied from 22 to 176 participants. The studies compared surgery with: splinting, corticosteroid injection, splinting and corticosteroid injection, platelet-rich plasma injection, manual therapy, multimodal non-operative treatment, unspecified medical treatment and hand support, and surgery and corticosteroid injection with corticosteroid injection alone. Since surgery is generally used for its long-term effects, this abstract presents only long-term results for surgery versus splinting and surgery versus corticosteroid injection. 1) Surgery compared to splinting in the long term (> 3 months) Surgery probably results in a higher rate of clinical improvement (risk ratio (RR) 2.10, 95% confidence interval (CI) 1.04 to 4.24; 3 studies, 210 participants; moderate-certainty evidence). Surgery probably does not provide clinically important benefit in symptoms or hand function compared with splinting (moderate-certainty evidence). The mean Boston Carpal Tunnel Questionnaire (BCTQ) Symptom Severity Scale (scale 1 to 5; higher is worse; minimal clinically important difference (MCID) = 1) was 1.54 with splint and 0.26 points better with surgery (95% CI 0.52 better to 0.01 worse; 2 studies, 195 participants). The mean BCTQ Functional Status Scale (scale 1 to 5; higher is worse; MCID 0.7) was 1.75 with splint and 0.36 points better with surgery (95% CI 0.62 better to 0.09 better; 2 studies, 195 participants). None of the studies reported pain. Surgery may not provide better health-related quality of life compared with splinting (low-certainty evidence). The mean EQ-5D index (scale 0 to 1; higher is better; MCID 0.074) was 0.81 with splinting and 0.04 points better with surgery (95% CI 0.0 to 0.08 better; 1 study, 167 participants). We are uncertain about the risk of adverse effects (very low-certainty evidence). Adverse effects were reported amongst 60 of 98 participants (61%) in the surgery group and 46 of 112 participants (41%) in the splinting group (RR 2.11, 95% CI 0.37 to 12.12; 2 studies, 210 participants). Surgery probably reduces the risk of further surgery; 41 of 93 participants (44%) were referred to surgery in the splinting group and 0 of 83 participants (0%) repeated surgery in the surgery group (RR 0.03, 95% CI 0.00 to 0.21; 2 studies, 176 participants). This corresponds to a number needed to treat for an additional beneficial outcome (NNTB) of 2 (95% CI 1 to 9). 2) Surgery compared to corticosteroid injection in the long term (> 3 months) We are uncertain if clinical improvement or symptom relief differs between surgery and corticosteroid injection (very low-certainty evidence). The RR for clinical improvement was 1.23 (95% CI 0.73 to 2.06; 3 studies, 187 participants). For symptoms, the standardised mean difference (SMD) was -0.60 (95% CI -1.88 to 0.69; 2 studies, 118 participants). This translates to 0.4 points better (95% CI from 1.3 better to 0.5 worse) on the BCTQ Symptom Severity Scale. Hand function or pain probably do not differ between surgery and corticosteroid injection (moderate-certainty evidence). For function, the SMD was -0.12 (95% CI -0.80 to 0.56; 2 studies, 191 participants) translating to 0.10 points better (95% CI 0.66 better to 0.46 worse) on the BCTQ Functional Status Scale with surgery. Pain (0 to 100 scale) was 8 points with corticosteroid injection and 6 points better (95% CI 10.45 better to 1.55 better; 1 study, 123 participants) with surgery. We found no data to estimate the difference in health-related quality of life (very low-certainty evidence). We are uncertain about the risk of adverse effects and further surgery (very low-certainty evidence). Adverse effects were reported amongst 3 of 45 participants (7%) in the surgery group and 2 of 45 participants (4%) in the corticosteroid injection group (RR 1.49, 95% CI 0.25 to 8.70; 2 studies, 90 participants). In one study, 12 of 83 participants (15%) needed surgery in the corticosteroid group, and 7 of 80 participants (9%) needed repeated surgery in the surgery group (RR 0.61, 95% CI 0.25 to 1.46; 1 study, 163 participants).

AUTHORS' CONCLUSIONS

Currently, the efficacy of surgery in people with CTS is unclear. It is also unclear if the results can be applied to people who are not satisfied after trying various non-surgical options. Future studies should preferably blind participants from treatment allocation and randomise people who are dissatisfied after being treated non-surgically. The decision for a patient to opt for surgery should balance the small benefits and potential risks of surgery. Patients with severe symptoms, a high preference for clinical improvement and reluctance to adhere to non-surgical options, and who do not consider potential surgical risks and morbidity a burden, may choose surgery. On the other hand, those who have tolerable symptoms, who have not tried non-surgical options and who want to avoid surgery-related morbidity can start with non-surgical options and have surgery only if necessary. We are uncertain if the risk of adverse effects differs between surgery and non-surgical treatments. The severity of adverse effects may also be different.

Long-Term Outcomes of Ultrasound-Guided Thread Carpal Tunnel Release and Its Clinical Effectiveness in Severe Carpal Tunnel Syndrome: A Retrospective Cohort Study

Ultrasound-guided thread carpal tunnel release (TCTR) was proposed as an effective and safe surgical technique with faster recovery and fewer complications. This study was conducted to confirm the long-term outcomes after TCTR and verify its clinical effectiveness in severe carpal tunnel syndrome (CTS) for more insights into TCTR procedure. A total of 168 TCTR procedures were performed in 152 individual patients by two physiatrists during 36-month period. In an assessment of 82 hands, surgical outcomes of 2 years after TCTR could be obtained, and the grade 6 CTS group of 21 hands, classified as extremely severe grade by Bland's classification, was compared with other severity groups (grade 1-5). The Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) was used to assess surgical outcomes. No adverse events occurred in all cases including the case of severe CTS and anatomical variants. TCTR showed significant improvement in BCTQ scale within 1-2 weeks, which continued up to 2 years with no recurrence (p < 0.01). Although slower and more progressive than the other severity group, there was also significant improvement relative to the BCTQ scale around 4 weeks after procedure in the grade 6 CTS group (p < 0.05). With the familiarity of ultrasound, ultrasound-guided TCTR is an effective and reliable surgical treatment for CTS in long-term outcomes and in severe CTS.

The role of electrodiagnosis in focal neuropathies

Electrodiagnostic (EDX) testing plays an important role in confirming a mononeuropathy, localizing the site of nerve injury, defining the pathophysiology, and assessing the severity and prognosis. The combination of nerve conduction studies (NCS) and needle electromyography findings provides the necessary information to fully assess a nerve. The pattern of NCS abnormalities reflects the underlying pathophysiology, with focal slowing or conduction block in neuropraxic injuries and reduced amplitudes in axonotmetic injuries. Needle electromyography findings, including spontaneous activity and voluntary motor unit potential changes, complement the NCS findings and further characterize chronicity and degree of axon loss and reinnervation. EDX is used as an objective marker to follow the progression of a mononeuropathy over time.

Nerve sonography in the diagnostic evaluation of primary and secondary carpal tunnel syndrome in rheumatoid arthritis

BACKGROUND AND PURPOSE

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy and extra-articular manifestation of rheumatoid arthritis (RA). However, in patients with RA, it is not always possible to clinically distinguish an actual CTS from other RA-based complaints.

METHODS

We evaluated the diagnostic role of nerve ultrasound (NUS) as supportive tool in the diagnostic process of CTS in patients with RA and tried to provide etiological clarification in cases of secondary CTS. Fifty-eight patients with RA and clinical suspicion of CTS were enrolled. All patients underwent a standardized clinical-neurological, electrophysiological (nerve conduction studies [NCS]), and NUS examination and completed the Boston CTS Questionnaire (BCTQ).

RESULTS

In 96 of 116 hands examined, a clinical suspicion of CTS was documented. In 43 of 96 (44.8%) CTS-positive hands, the diagnosis was primarily confirmed by NCS, whereas in another 16 of 96 (30.2%) hands, the diagnosis could only be verified by NUS, leading to a diagnosis of CTS in 59 of 116 (50.8%) hands. In 19 of 59 (32.3%) CTS-positive hands, tenosynovial hypertrophy was observed, and in 7 of 59 (11.8%), a cystic mass was identified as the underlying cause of secondary CTS. A good correlation between NCS and NUS findings was documented, but no significant correlation was found between NCS, NUS, and clinical findings/BCTQ.

CONCLUSIONS

In people with RA, a diagnosis of CTS purely on a clinical basis is nonspecific and should be supported by NCS and/or NUS. NUS markedly facilitates the diagnosis of CTS in these patients and enables differentiation between primary and secondary causes.

Use of nerve conduction studies in carpal tunnel syndrome

This review article examines the use of nerve conduction studies in the management of carpal tunnel syndrome. These studies should be understood not as a test that determines the diagnosis but as a measure of impaired nerve function. They are sensitive indicators of local demyelination and axonal loss that can detect and quantify these changes before the appearance of clinical signs, providing information that cannot be obtained with the unaided senses of the physician, nor by any other investigation. They are the best available indicator of overall disease severity, correlating with symptoms and anatomical change in the median nerve. They have some prognostic value for surgical outcome and are sufficiently sensitive to change for the evaluation of treatment response. When surgery does not yield the expected improvement in symptoms, they can help to establish whether decompression has been achieved provided preoperative results are available for comparison.

Ultrasonographic Measurement of Median Nerve Cross-Sectional Area in Evaluating Carpal Tunnel Release Outcomes

PURPOSE

Earlier research has explored carpal tunnel release (CTR) surgery outcomes using electrodiagnostic tests (EDX). However, evaluation of the median nerve before and after CTR by ultrasound (US) is understudied. This study aimed to establish the outcomes of CTR by EDX and US, and examine the correlation between the clinical improvement and US after CTR.

METHODS

The sample consisted of 172 wrists that underwent CTR. Pain was assessed using the visual analog scale (VAS). The Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), including the symptom severity and function subscales, was applied before and 3 months after CTR. The proximal and distal cross-sectional areas (CSAs) of the median nerve were measured using US, and EDX was performed before and 3 months after CTR.

RESULTS

Patients had mean preoperative and postoperative VAS scores of 7.7 ± 1.2 and 1.7 ± 1.2, respectively. The mean preoperative and postoperative proximal CSA measurements were 16.4 ± 4.5 mm2 and 12.1 ± 3.9 mm2, respectively. The mean preoperative and postoperative distal CSA measurements were 13.6 ± 3.7 mm2 and 11.0 ± 3.1 mm2, respectively. A significant improvement was observed in VAS, BCTQ, and EDX 3 months after CTR. A weak, positive correlation was observed between the improvement in the BCTQ symptom severity and function subscales and CSAs following CTR.

CONCLUSIONS

The results of this study demonstrate that preoperative median nerve CSA values may be used in evaluating CTR outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Preoperative electrodiagnostic studies and postoperative outcomes for ulnar mononeuropathy at the elbow: A systematic review

OBJECTIVE

To analyze the association between preoperative electrodiagnostic (EDX) studies and postoperative pain and functional outcomes following ulnar nerve decompression and/or transposition for ulnar neuropathy at the elbow (UNE).

LITERATURE SURVEY

Protocol was submitted and database search was conducted by an experienced librarian of all available studies in the English language from 1990 to June 8, 2022. Databases included Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, and Scopus.

METHODOLOGY

Inclusion criteria consisted of randomized controlled trials, prospective and retrospective longitudinal studies, and studies involving adults ≥18 years of age who underwent ulnar nerve decompression and/or transposition for UNE. Study quality and risk of bias were assessed using the National Heart, Lung, and Blood Institute (NHLBI) Study Quality of Assessment Tool. Certainty in evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. A meta-analysis was not performed.

SYNTHESIS

A total of 289 studies were screened, and 8 retrospective cohort studies met inclusion criteria comprising 762 patients. A decreased or absent preoperative sensory nerve action potential amplitude (SNAP) showed significance with worse postoperative outcomes. The presence of preoperative conduction block showed significance in higher quality studies. There was limited evidence for slow preoperative motor conduction velocities or preoperative electromyography (EMG) abnormalities and postoperative outcomes. Overall quality assessment demonstrated that two studies had "good," four "fair," and two "poor" quality of evidence. Certainty in evidence was "low" due to risk of bias.

CONCLUSIONS

A decreased or absent preoperative ulnar SNAP may predict worse postoperative outcomes. Per higher quality studies, preoperative conduction block at the elbow may also predict worse postoperative outcomes. Careful interpretation is required with a full understanding of the limited evidence, risk of bias, and low certainty in evidence to support the use of preoperative EDX to predict postoperative outcomes in UNE.

Characteristics of diabetic and non-diabetic carpal tunnel syndrome in terms of clinical, electrophysiological, and Sonographic features: a cross-sectional study

BACKGROUND

Although diabetes is considered a major risk factor for carpal tunnel syndrome (CTS), the characteristics of diabetic CTS have not been fully understood.

OBJECTIVE

This study is aimed at evaluation of the clinical, electrophysiological, and ultrasonographic findings of non-diabetic and diabetic CTS.

METHODS

This retrospective, cross-sectional study included patients diagnosed with CTS. Patient age, sex, involved side, body mass index, clinical and electrophysiological findings, and median nerve cross-sectional area (CSA) were identified. Diabetes was identified through patient or guardian interviews, medical records, and medication history. Linear and binary logistic regression models were established to confirm the associations between the electrophysiological findings, median nerve CSA, and clinical outcomes. Covariates, such as age, sex, body mass index, diabetes, symptom duration, and thenar muscle weakness were adjusted.

RESULTS

Out of the 920 hands, 126 and 794 belonged to the diabetic and non-diabetic CTS groups, respectively. The patients were significantly older in the diabetic CTS group (P < 0.001). The rate of thenar weakness in the diabetic CTS group was also significantly higher than that in the non-diabetic CTS group (P = 0.009). The diabetic CTS group had a more severe electrodiagnostic grade (P = 0.001). The prolonged onset latency of the compound motor nerve action potential (CMAP) and median nerve CSA were well associated with the degree of clinical symptoms. Increased median nerve CSA was significantly associated with prolonged CMAP onset latency (β = 0.64; P = 0.012), prolonged transcarpal latency (β = 0.95; P = 0.044), and decreased CMAP amplitude (β = -0.17; P = 0.002) in the non-diabetic CTS group.

CONCLUSION

Diabetic CTS had more profound electrophysiological abnormalities. Distal motor latency and median nerve CSA were not only associated with each other, but also with clinical symptoms. Further studies are needed to investigate the pathophysiological mechanisms underlying diabetic CTS.

Wide-awake local anesthesia no tourniquet and dexamethasone (WALANT-D) for modified Camitz opponens plasty in severe carpal tunnel syndrome-a retrospective study of 30 cases

Background

To analyze the outcome of modified Camitz opponens plasty using the wide-awake local anesthesia no tourniquet with dexamethasone (WALANT-D) technique in severe carpal tunnel syndrome (CTS).

Methods

A retrospective review was performed in 30 hands of 27 patients who underwent Camitz opponens plasty for severe CTS between 2019 and 2021. All patients had 8 mg of dexamethasone mixed with WALANT. Preoperative active palmar abduction, grip strength, side, and pulp pinch strength, Kapandji score, and electrophysiological assessment of compound muscle action potential (CMAP) for abductor pollicis brevis (APB) were compared with the postoperative values. The palmaris longus had dual insertion into the abductor pollicis brevis and extensor expansion. The time interval of post-operative pain-free was noted. The Disabilities of the Arm, Shoulder, and Hand (DASH) and Carpal Tunnel Syndrome instrument (CTSI) also assessed the functional outcome.

Results

The mean age of patients was 35 years (range 32-58 years). There were five male and 22 female patients. Of the female patients, three females had severe bilateral CTS. Twenty right and ten left hands were affected. The mean follow-up of our study was 12.5 months (range 10-14 months). The patients were pain-free for an average of 19.5 h postoperatively. There was a significant improvement in the thumb palmar abduction, grip strength, side, and pulp pinch strength, DASH score, CTSI, and APB-CMAP (p < 0.05) at the final follow-up.

Conclusions

Modified Camitz opponens plasty with a dual insertion into APB and extensor expansion effectively improves thumb opposition and daily activities. The tendon tensioning, checking the pulley impingement, appreciation of active movements, and a comfortable patient operative experience are advantages of the WALANT. Adding dexamethasone as an adjuvant to WALANT prolongs the analgesia and duration of the nerve block.

Level of evidence

IV, Retrospective case study.

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).

Bilateral Idiopathic Carpal Tunnel Syndrome: Clinical-Functional Characterization and Efficacy of Two Combined Postoperative Physiotherapeutic Treatments

OBJECTIVE

To evaluate the efficacy of combined association instrument myofascial mobilization (IASTM) and stretching in patients with idiopathic bilateral carpal tunnel syndrome (CTS) operated on one hand and to analyze the response of the operated (OH) and non-operated (NH) hand according to the sequence of therapies. Research on these parameters has not yet been found in the literature.

METHODS

Randomized controlled crossover study with 43 participants using the objective and subjective outcome variables. Patients were randomly assigned to two groups: starting with stretching followed by IASTM and starting with IASTM followed by stretching. Then patients underwent surgery on the hand with more severe involvement and physical therapy rehabilitation was started 30 days after for a period of 4 weeks. After the 1-week interval the participants who started with stretching were referred to IASTM and vice versa, following the same previous patterns. The outpatient reassessments took place at 3 to 6 months. Crossover ANOVA and effect sizes were used as analysis methods.

RESULTS

Time was the most significant outcome for all variables both during therapies and at 6-month follow-up. Regarding response to the combined therapies between OH and NH, there were differences for both OH and NH, with the greatest impact on NH for the palmar grip and VAS variables. The treatment sequences were significant for pain on the NH and mental SF-12, suggesting that starting with IASTM followed by stretching had a superior outcome for these outcomes.

CONCLUSION

The combination of IASTM with stretching, used in the postoperative period of bilateral idiopathic CTS, proved to be supplementary, with significant results and large effect sizes for most of the outcomes assessed, both during the time of application of the therapies and in the 6-month follow-up for both hands, and may constitute a viable therapeutic alternative for this population.

The significance of wrist immobilization for endoscopic carpal tunnel release

Background

Over the years, endoscopic carpal tunnel release (ECTR) has gained significant interest as an alternative to surgery. However, no consensus has been reached on the necessity of postoperative wrist immobilization. This study aims to compare the outcomes of wrist immobilization for a period of 2 weeks to immediate wrist mobilization after ECTR.

Methods

A total of 24 patients with idiopathic carpal tunnel syndrome undergoing dual-portal ECTR from May 2020 to Feb 2022 were enrolled and randomly divided into two groups postoperatively. In one group, patients wore a wrist splint for 2 weeks. In another group, wrist mobilization was allowed immediately after surgery. The two-point discrimination test (2PD test); the Semmes-Weinstein monofilament test (SWM test); the occurrence of pillar pain, digital and wrist range of motion (ROM); grip and pinch strength; the visual analog score (VAS), the Boston Carpal Tunnel Questionnaire (BCTQ) score; the Disabilities of the Arm, Shoulder, and Hand (DASH) score; and complications were evaluated at 2 weeks and 1, 2, 3, and 6 months after the surgery.

Results

All 24 subjects finished this study with no dropouts. During the early follow-up, patients with wrist immobilization demonstrated lower VAS scores, lower occurrence of pillar pain, and higher grip and pinch strength compared with the immediate mobilization group. No significant difference was obtained between these two groups in terms of the 2PD test, the SWM test, digital and wrist ROM, BCTQ, and the DASH score. In total, two patients without splints reported transient scar discomfort. No one complained of neurapraxia, injury of the flexor tendon, median nerve, and major artery. At the final follow-up, no significant difference was found in any parameters between both groups. The local scar discomfort mentioned above disappeared and left no serious sequela.

Conclusion

Wrist immobilization during the early postoperative period demonstrated significant pain alleviation along with stronger grip and pinch strength. However, wrist immobilization yielded no obvious superiority regarding clinical outcomes at the final follow-up.

Median nerve ultrasound cross sectional area and wrist-to-forearm ratio in relation to carpal tunnel syndrome related axonal damage and patient age

Objective

Primary objective was to retrospectively examine the effects of patient age and carpal tunnel syndrome (CTS) related axon loss on median nerve (MN) high resolution ultrasound (HRUS) in younger and older patients. HRUS parameters evaluated in this study were MN cross sectional area at the wrist (CSA) and wrist-to-forearm ratio (WFR).

Methods

The material comprised 467 wrists of 329 patients. The patients were categorized into younger (<65 years) and older (≥65 years) groups. Patients with moderate to extreme CTS were included in the study. Axon loss of the MN was assessed by needle EMG and graded by the interference pattern (IP) density. The association between axon loss and CSA and WFR was studied.

Results

The older patients had smaller mean CSA and WFR values compared to the younger patients. CSA correlated positively to the CTS severity only in the younger group. However, WFR correlated positively to CTS severity in both groups. In both age groups, CSA and WFR correlated positively with IP reduction.

Conclusions

Our study complemented recent findings on the effects of patient age on the CSA of the MN. However, although the MN CSA did not correlate with the CTS severity in older patients, the CSA increased in respect to the amount of axon loss. Also, as a new result, we presented the positive association of WFR with CTS severity among older patients.

Significance

Our study supports the recently speculated need for different MN CSA and WFR cut-off values for younger and older patients in assessing the severity of CTS. With older patients, WFR may be a more reliable parameter to assess the CTS severity than the CSA. CTS related axonal damage of the MN is associated to additional nerve enlargement at the carpal tunnel intel site.

Potential Relationships between the Median Nerve Cross-Sectional Area and Physical Characteristics in Unilateral Symptomatic Carpal Tunnel Syndrome Patients

Background: The present study investigated the relationships between the median nerve cross-sectional area (CSA) and physical characteristics in patients with unilateral symptomatic carpal tunnel syndrome (CTS). Methods: Height, weight, body mass index (BMI), disease duration, results of electrodiagnostic testing (EDX), and median nerve CSA at the level of the wrist crease were recorded in 81 patients with CTS who presented with symptoms on only one side. Correlation coefficients between median nerve CSA and physical characteristics, disease duration, and results of EDX were analyzed. Results: Median nerve CSA at the wrist crease (mm2) was significantly larger on the symptomatic side (14.1 ± 3.8) than on the asymptomatic side (11.5 ± 2.9). Median nerve CSA correlated with body weight (correlation coefficient = 0.39) and BMI (correlation coefficient = 0.44) on the asymptomatic side, but not on the symptomatic side. These correlations were slightly stronger in females (correlation coefficient = 0.46) than in males (correlation coefficient = 0.40). No correlations between median nerve CSA and disease duration and the results of EDX were observed in both sides. Conclusions: In patients with unilateral symptomatic CTS, median nerve CSA correlated with BMI only on the asymptomatic side. The present results suggest that the relationship between median nerve CSA and BMI in CTS is significant until symptom onset but may be masked by edema and pseudoneuroma after its onset. A higher BMI is associated with a larger CSA of the median nerve, which may be a risk factor for the development of CTS.

Application of deep learning algorithms in automatic sonographic localization and segmentation of the median nerve: A systematic review and meta-analysis

OBJECTIVE

High-resolution ultrasound is an emerging tool for diagnosing carpal tunnel syndrome caused by the compression of the median nerve at the wrist. This systematic review and meta-analysis aimed to explore and summarize the performance of deep learning algorithms in the automatic sonographic assessment of the median nerve at the carpal tunnel level.

METHODS

PubMed, Medline, Embase, and Web of Science were searched from the earliest records to May 2022 for studies investigating the utility of deep neural networks in the evaluation of the median nerve in carpal tunnel syndrome. The quality of the included studies was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies. The outcome variables included precision, recall, accuracy, F-score, and Dice coefficient.

RESULTS

In total, seven articles were included, comprising 373 participants. The deep learning and related algorithms comprised U-Net, phase-based probabilistic active contour, MaskTrack, ConvLSTM, DeepNerve, DeepSL, ResNet, Feature Pyramid Network, DeepLab, Mask R-CNN, region proposal network, and ROI Align. The pooled values of precision and recall were 0.917 (95 % confidence interval [CI], 0.873-0.961) and 0.940 (95 % CI, 0.892-0.988), respectively. The pooled accuracy and Dice coefficient were 0.924 (95 % CI, 0.840-1.008) and 0.898 (95 % CI, 0.872-0.923), respectively, whereas the summarized F-score was 0.904 (95 % CI, 0.871-0.937).

CONCLUSION

The deep learning algorithm enables automated localization and segmentation of the median nerve at the carpal tunnel level in ultrasound imaging with acceptable accuracy and precision. Future research is expected to validate the performance of deep learning algorithms in detecting and segmenting the median nerve along its entire length as well as across datasets obtained from various ultrasound manufacturers.

The sensitivity of median versus ulnar palmar mixed nerve study in the early diagnosis of carpal tunnel syndrome

Background

Electrodiagnostic tests (EDX) are the most frequent and applicable studies in early diagnosis of carpal tunnel syndrome (CTS), but the definitive sensitive and specific tests are still under study. We aimed to evaluate the role of the median versus ulnar palmar mixed nerve study (Mix M-U), and its sensitivity in comparison to other provocative comparison studies, in supporting the early diagnosis of CTS. This cross-sectional study included 142 idiopathic early CTS hands from 100 patients and 71 hands from 50 healthy subjects as a control group. We did routine median motor and sensory studies and 4 comparative tests namely median versus radial sensory study (MVR), Mix M-U, median versus ulnar sensory study (MVU), and median versus ulnar lumbrical-interossei motor study (LU-IN).

Results

The routine median motor and sensory latency and amplitude showed a statistically significant difference between CTS and control groups as (p< 0.05) and a highly statistically significant difference between the 2 groups as regards the 4 comparative tests as (p< 0.0001). The specificities of all the 4 comparative tests were higher than 90%. MVR test had the highest sensitivity (92.2%) and followed by Mix M-U study (82.2%) and MVU (78.7%), and the least sensitive test was the LM-IN (66.9%).

Conclusions

Although the patients’ results fall within the normal range according to the reference range in the literature, it showed a statistically significant difference when compared to controls. A high percentage of those symptomatic patients showed results of typical CTS when tested with the comparative studies so there is a need to use these sensitive tests to diagnose cases with early CTS. According to sensitivity studies, the selection of which tests to do in order is a challenging choice. For the diagnosis of cases with early CTS with a normal ordinary motor and sensory studies, MVR comparative technique appeared as the best sensitive and specific provocative electrophysiological test followed by the Mix M-U test. We recommend the use of a combination of both tests first in the diagnosis of early CTS and if one of them was negative we can use the other comparative studies MVU and then LM-IN studies.

Infrared thermographic changes after decompression surgery in patients with carpal tunnel syndrome

BACKGROUND

Digital infrared thermal imaging (DITI), which detects infrared rays emitted from body surface to create a body heat map, has been utilized at various musculocutaneous conditions. Notably, DITI can demonstrate autonomic vasomotor activity in the nerve-innervated area, and thus may be of use in carpal tunnel syndrome (CTS). In this study, we compared DITI findings before and after carpal tunnel release (CTR) surgery in patients with unilateral CTS to investigate the corresponding neurophysiological changes.

METHODS

In this retrospective cohort study, DITI parameters such as the temperature differences between the median and ulnar nerve territories and median nerve-innervated digital anisometry were measured. Subjective symptom duration, pain scale, and ultrasonographic findings were also compared before and after CTR. Patients were evaluated before and 6 weeks after CTR, respectively.

RESULTS

A total of 27 patients aged 59.0 ± 11.2 years were finally included. After CTR, median nerve-innervated thermal anisometry was improved (2.55 ± 0.96 °C to 1.64 ± 1.34 °C; p = 0.003). The temperature differences between the median and ulnar nerve territories were not significantly changed. Subjective pain, the Simovic Weinberg Clinical Scale, and palmar bowing of the flexor retinaculum were also significantly improved (p <  0.001 for all comparisons).

CONCLUSIONS

Our results demonstrated that DITI findings could reflect an improvement in autonomic function after CTR. Therefore, DITI can be an objective method to assess pre- and post-operative neurophysiologic changes in CTS.

Ultrasonographic Assessment of the Safe Zone for Carpal Tunnel Intervention: A Comparison Between Healthy Individuals and Patients With Carpal Tunnel Syndrome

OBJECTIVE

To compare transverse and longitudinal safe zones using ultrasonography between healthy individuals and patients with carpal tunnel syndrome (CTS).

METHODS

This was a prospective observational case-control study. Forty wrists from 20 healthy individuals and 40 wrists from 24 patients with CTS were examined. Patients with CTS were classified into three groups (mild, moderate, and severe CTS) based on electrodiagnostic findings. Using ultrasonography, we measured the distance between the median nerve and ulnar vessels to identify the transverse safe zone, and between the distal flexor retinaculum and superficial palmar artery arch to identify the longitudinal safe zone.

RESULTS

The transverse and longitudinal safe zones were significantly different between participants with CTS and those without CTS. The transverse safe zone significantly differed between the mild and severe CTS groups, while the longitudinal safe zone was not significantly different between the groups. The cross-sectional area of the median nerve negatively correlated with the transverse and longitudinal safe zones.

CONCLUSION

Transverse and longitudinal safe zones were narrower in patients with CTS than in the healthy group. A significant difference was observed between patients with mild CTS and those with severe CTS. Furthermore, the cross-sectional area of the median nerve was directly proportional to the degree of narrowing of the transverse and longitudinal safe zones.

Ultrasound of the Median Nerve in the Surgical Treatment of Severe Carpal Tunnel Syndrome

BACKGROUND

High-resolution ultrasound (HRU) has demonstrated utility in the diagnosis and treatment of carpal tunnel syndrome (CTS) by measuring the cross-sectional area (CSA) of the median nerve. We investigated whether HRU could be helpful in evaluating outcomes of carpal tunnel release in patients with severe CTS.

METHODS

Patients greater than 18 years of age with severe CTS on electrodiagnostic (EDX) studies and scheduled to have carpal tunnel release were enrolled. At baseline visit within 6 weeks preoperatively, HRU was used to measure median nerve CSA at the carpal tunnel inlet and forearm, and the wrist/forearm ratio (WFR) was calculated. Patients also completed the Boston Carpal Tunnel Questionnaire (BCTQ). Ultrasound and BCTQ were repeated at 6 weeks and 6 months postoperatively.

RESULTS

Twelve patients completed the study (average age, 69 years; range, 52-80 years). The WFR improved significantly at 6 weeks and reached normal levels at 6 months. The CSA at the wrist also improved at 6 months, although this did not reach statistical significance (P = .059). Boston Carpal Tunnel Questionnaire symptoms and function scores improved significantly at 6 weeks and 6 months.

CONCLUSIONS

High-resolution ultrasound provides an objective assessment of surgical outcomes in cases of severe CTS, demonstrating normalization of WFR in our series of successful cases. Future study of poor outcomes may help determine whether improvement in WFR and CSA can provide reassurance and support for observation rather than reoperation. Ultrasound also provides anatomical evaluation and may be helpful in cases with medicolegal or psychosocial issues while potentially being less costly and better tolerated than EDX or magnetic resonance imaging.

A prospective cohort study: platelet-rich plasma combined with carpal tunnel release treating carpal tunnel syndrome

Background

PRP injection was proved to promote the health condition of individuals with mild to moderate Carpal Tunnel Syndrome (CTS). However, carpal tunnel release (CTR) was still a necessary treatment for individuals with moderate and severe CTS.

Methods

To explore whether adjuvant PRP treatment would improve the prognosis while using CTR, we included 82 patients in this study. Preoperative and postoperative visual analog scale (VAS), Boston carpal tunnel syndrome questionnaire-symptom severity scale (BCTQ-SSS), Boston carpal tunnel syndrome questionnaire-functional status scale (BCTQ-FSS), and grip strength were used to examine the patient's symptoms and function.

Results

CTR combined with PRP treatment improved the VAS (1.9 ± 0.5 versus 1.4 ± 0.4, P < .05), BCTQ-SSS (1.8 ± 0.4versus 1.5 ± 0.3, P < .05) and BCTQ-FSS (1.8 ± 0.5 versus 1.4 ± 0.6, P < .05) in patients with moderate symptoms within one month after surgery. At the same time, it does not show any advantages in treating individuals with severe carpal tunnel syndrome.

Conclusions

PRP does not affect long-term prognosis while increasing the surgery cost. To conclude, PRP as an adjuvant treatment of CTR has limited effect. Considering the additional financial burden on patients, CTR combined with PRP should be cautious in CTS treatment.

Long-Term Outcome of Electrodiagnostic Values and Symptom Improvement After Carpal Tunnel Release: A Retrospective Cohort Study

PURPOSE

The aim of this study was to evaluate electrodiagnostic studies and clinical outcomes after carpal tunnel release surgery in moderate and severe cases of carpal tunnel syndrome (CTS).

METHODS

Seventy-two patients with moderate or severe CTS who underwent carpal tunnel release surgery (46 unilateral; 26 bilateral; total, 98 surgeries) between 2009 and 2014 were included in the study. The cases were divided into 2 groups according to electrodiagnostic results: those with moderate CTS and those with severe CTS. Michigan Hand Outcomes Questionnaire scores and electrodiagnostic data (sensory nerve action potentials and compound muscle action potentials) were recorded before surgery and in postoperative follow-up studies obtained at 3 months, 1 year, and 5 years.

RESULTS

There were 56 surgeries in the moderate CTS group and 42 surgeries in the severe CTS group. Sensory nerve action potentials and compound muscle action potentials were significantly lower in the severe CTS group when compared to the moderate CTS group at all follow-up times. There was a significant difference in Michigan Hand Outcomes Questionnaire scores between the groups before surgery, but no significant differences at the final follow-up. It was found that the values of all parameters (sensory nerve action potentials, compound muscle action potentials, and Michigan Hand Outcomes Questionnaire score) demonstrated significant improvements with time in both the severe and the moderate CTS groups.

CONCLUSIONS

Carpal tunnel release surgery improves symptoms, regardless of the preoperative severity. Postoperative electrodiagnostic study results of patients with moderate CTS improve to a greater degree than those of patients with severe CTS, but all remain abnormal.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognosis IIb.

Ultrasound-guided 5% dextrose prolotherapy versus corticosteroid injection in carpal tunnel syndrome: a randomized, controlled clinical trial

Aim: The main assessment of this study is to analyze the efficiency of ultrasound-guided dextrose prolotherapy against corticosteroid injections for the treatment of carpal tunnel syndrome. Materials & methods: A total of 54 patients with carpal tunnel syndrome were included. Patients who were assigned into the prolotherapy group were injected with 5cc 5% dextrose water under ultrasound guidance. Patients in the corticosteroid group received ultrasound-guided 1 ml triamcinolone 40 mg/ml injection. Results: The inter-group analysis revealed that dextrose prolotherapy has a similar efficacy as corticosteroid for improving pain intensity, functional limitation in daily life, electrophysiologic parameters and ultrasonographic outcomes. No remarkable difference was found between the two treatments until 3 months of follow-up. Conclusion: Dextrose 5% has similar efficacy as triamcinolone for improving pain intensity, functional limitation in daily life, electrophysiologic parameters and ultrasonographic outcomes.

Comparison of Radial Extracorporeal Shock Wave Therapy and Local Corticosteroid Injection Effectiveness in Patients With Carpal Tunnel Syndrome: A Randomized Controlled Study

OBJECTIVE

The aim of the study was to compare the effectiveness of radial extracorporeal shock wave therapy and local corticosteroid injection on pain, function, and nerve conduction studies in the treatment of idiopathic carpal tunnel syndrome.

DESIGN

A total of 72 patients who were diagnosed as having carpal tunnel syndrome were included in the study. The radial extracorporeal shock wave therapy group received radial extracorporeal shock wave therapy, the local corticosteroid injection group received local corticosteroid injection, and the control group only used a resting hand splint. The patients were evaluated using a Visual Analog Scale-pain, a Visual Analog Scale-numbness, the Boston Symptom Severity Scale, the Boston Functional Status Scale, and handgrip strength tests before treatment 1 and 12 wks after the treatment.

RESULTS

Both clinical and nerve conduction study parameters improved with all three groups, and this effect continued at the 12th-week follow-up of the patients. The Visual Analog Scale-pain, Visual Analog Scale-numbness, Boston Symptom Severity Scale, and Boston Functional Status Scale scores in the first week after the treatment, as well as Visual Analog Scale-pain and Boston Functional Status Scale scores in the 12th week after the treatment, were significantly lower in the local corticosteroid injection group compared with the other two groups.

CONCLUSIONS

Our study revealed the success of radial extracorporeal shock wave therapy, splint, and local corticosteroid injection, but symptom relief was greater in the first week and 12th week with local corticosteroid injection.

Hydrodissection for Carpal Tunnel Syndrome: A Systematic Review

ABSTRACT

Hydrodissection is an ultrasound-guided technique that has received more attention recently for its role in nerve entrapment syndromes. The purposes of this systematic review were to evaluate the safety and effectiveness of hydrodissection in carpal tunnel syndrome and to investigate the ideal parameters for injectate type, dosage, volume, and frequency; injection approach and technique; as well as operator experience and training required. We searched the Embase, MEDLINE, and PubMed databases with supplemental searches in the CINAHL, Web of Science, and Google Scholar databases for relevant randomized controlled trials. Primary outcome measures were adverse outcomes and clinical effectiveness. Six randomized controlled trials involving 356 wrists were included. All studies used ultrasound guidance in their interventions. No safety-related adverse outcomes were found, although not all studies declared this. Only one study was placebo controlled and revealed symptomatic as well as functional improvements at 6 mos, whereas the rest investigated hydrodissection with different injectate types. We concluded that nerve hydrodissection for carpal tunnel syndrome can be safely performed under ultrasound guidance. However, it is unclear whether the hydrodissection mechanism truly causes improvements in clinical outcomes. We were also unable to draw conclusions regarding the ideal procedure-related parameters. We recommend that future work should not only investigate safety and clinical effectiveness but also attempt to clarify the ideal procedure-related parameters.

Ultrasound improves motor distal latency on patients with carpal tunnel syndrome: systematic review and meta-analysis

INTRODUCTION

Is the application of ultrasound effective on pain, the severity of the symptoms, physical function, strength, and neurophysiological parameters of the median nerve conduction in patients with carpal tunnel syndrome?

EVIDENCE ACQUISITION

A systematic review and meta-analysis of randomized controlled trials was performed by using a structured search strategy in Scopus, CINAHL, Web of Science and PEDro databases. All the primary studies included samples with carpal tunnel syndrome treated by: ultrasound versus no treatment, therapeutic ultrasound versus sham ultrasound, ultrasound and usual care versus usual care, or ultrasound and other intervention versus the same intervention. The outcomes measures registered were pain, severity of symptoms, function, strength, and neurophysiological parameters (motor distal latency and sensory distal latency) of the median nerve. Methodological quality was evaluated by PEdro Scale.

EVIDENCE SYNTHESIS

Ten clinical trials met the inclusion criteria for the systematic review. Eight trials were meta-analyzed, which included a total of 2069 patients with carpal tunnel syndrome. The methodological quality of the included studies ranged among limited (5 trials), moderate (3 trials), and high (2 trials). In one of the electrophysiological parameters (motor distal latency), a significant difference between groups after the use of ultrasound was observed (MD=-0.10; fixed 95% CI=-0.20, -0.01; P=0.04). No significant differences between groups were observed at post-treatment for pain (P=0.29), severity of symptoms (P=0.99), function (P=0.54), strength (P=0.27) and for the rest of the electrophysiological parameters evaluated (P>0.05).

CONCLUSIONS

The use of ultrasound on patients with carpal tunnel syndrome seems to improve motor distal latency. This finding implies a partial improvement at the neurophysiological level, representing a reduction in the grade of clinical severity. Additional clinical trials with a high methodological quality are needed to investigate the doses at which ultrasound are most effective.

Return to work following ultrasound guided thread carpal tunnel release versus open carpal tunnel release: a comparative study

A retrospective review of hospital employees at a single employer institution who underwent ultrasound guided thread carpal tunnel release (TCTR) or open carpal tunnel release (OCTR) between January 2018 and August 2020 was performed to ascertain differences in return-to-work status. Patient age, sex, occupation, handedness, severity of carpal tunnel syndrome, prior treatments and surgical outcomes were reviewed. A total of 18 patients underwent TCTR and 17 patients underwent OCTR. The TCTR group averaged 12 days to return to work without restrictions, as opposed to 33 days for the OCTR group. Resolution of symptoms was afforded in all patients without any complications regardless of surgical technique. While both TCTR and OCTR were effective, our data indicates that TCTR resulted in a shorter return to work.Level of evidence: III.

Contradições diagnósticas na síndrome do túnel do carpo

Objetivo Diante da divergência sobre a necessidade de exames complementares, como ultrassonografia (US) e eletroneuromiografia (ENMG) para o diagnóstico da síndrome do túnel do carpo (STC), objetivamos elucidar qual deles apresenta maior precisão na confirmação da presença ou não desta afecção.

Métodos Um total de 175 pacientes de um ambulatório de cirurgia da mão foram avaliados clinicamente, e os resultados dos testes clínicos (Tinel, Phalen e Durkan), da US (normal ou alterada) e da ENMG (normal, leve, moderada e grave) foram anotados, cruzados, e submetidos a análise estatística para verificar a concordância entre eles.

Resultados A idade média da amostra era de 53 anos, sendo prevalente o sexo feminino (159 casos). Dos pacientes com teste clínico positivo, 43,7% apresentavam US normal, e 41,7%, ENMG sem alterações. Foram encontrados resultados negativos no Tinel em 46,9% no Phalen em 47,4%, e no Durkan em 39,7%. No cruzamento entre a ENMG e os demais métodos diagnósticos, houve pouca concordância estatística.

Conclusão Não houve concordância entre os resultados dos exames clínicos, da US e da ENMG no diagnóstico da STC, e não há exame clínico ou complementar para STC que determine a conduta terapêutica com precisão.

Nível de Evidência IV, Série de Casos.

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.

Ultrasound Measurements of the Median Nerve at the Distal Wrist Crease Correlate With Electrodiagnostic Studies

Background: Carpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy and is commonly evaluated using electrodiagnostic studies (EDSs). Ultrasound (US) has emerged as a potentially easier and more comfortable alternative to EDSs. The purpose of this study is to evaluate whether measurements of the cross-sectional area (CSA) of the median nerve via US correlate with the severity rating of CTS based on EDSs. Methods: A retrospective review of patients aged 18 years or older who underwent US and EDSs of the median nerve for CTS was performed. Sensory nerve action potential, distal motor latency, and compound muscle action potential were measured, and severity was graded on American Association of Neuromuscular and Electrodiagnostic Medicine guidelines. Cross-sectional area of the median nerve was measured via US at the wrist crease. Results: There was a significant association between increasing CSA and increasing EDS severity (P < .0001). The mean CSA for normal, mild, moderate, and severe CTS was 7.48 ± 2.00, 10.36 ± 2.53, 12.01 ± 3.64, and 14.34 ± 4.77 mm², respectively. The area under the curve demonstrated the ability of median nerve CSA to discriminate between normal and abnormal EDSs with an optimal cutoff CSA of ≥10 mm², as well as, the ability to discriminate between mild CTS and moderate to severe CTS at a cutoff CSA of greater than or equal to 12 mm². Conclusions: The results of this study show that US measurements of the median nerve at the distal wrist crease discriminate between normal and abnormal EDSs, and between mild CTS and moderate to severe CTS.

Cross-sectional Area Ratio of Median-to-Ulnar and Median-to-Superficial Radial Nerve at the Wrist for Diagnosis of Carpal Tunnel Syndrome

Objectives:

This study aimed to evaluate the diagnostic properties for carpal tunnel syndrome (CTS) of the median-to-ulnar cross-sectional area ratio (MUR) and the median-to-superficial radial cross-sectional area ratio (MRR).

Methods:

A case–control study was conducted. A physiatrist, blinded to the CTS status of the subjects, assessed the cross-sectional area of the median nerve (CSA-m), MUR, and MRR at the distal wrist crease for the CTS and control groups. The relationship of CSA-m, MUR, and MRR with CTS severity was tested using Spearman’s correlation. The overall diagnostic accuracy was determined using the area under the receiver operating characteristic curve (AUC). The cut-off values to diagnose CTS were chosen to achieve similar values for sensitivity and specificity.

Results:

There were 32 hands in the CTS group and 33 hands in the control group. The correlations of CSA-m, MUR, and MRR with CTS severity were 0.66, 0.56, and 0.34, respectively. The AUCs of CSA-m, MUR, and MRR were 0.86 (95%CI: 0.77–0.95), 0.79 (0.69–0.90), and 0.69 (0.56–0.82), respectively. The cut-off values of CSA-m, MUR, and MRR were 12 mm² (sensitivity, 81.3%; specificity, 81.8%), 2.6 (sensitivity, 68.8%; specificity, 69.7%), and 10 (sensitivity, 65.6%; specificity, 63.6%), respectively.

Conclusions

: MUR and MRR had acceptable diagnostic abilities but did not show superiority over CSA-m for CTS diagnosis.

Diagnosis of carpal tunnel syndrome in non-diabetic patients with hemodialysis using ultrasound: Is it a useful adjunctive tool?

OBJECTIVE

(1) To examine the ultrasound (US) characteristics in patients with hemodialysis-related carpal tunnel syndrome (H-CTS) and (2) to evaluate the accuracy of a proposed US parameter-dynamic ratio of median nerve-to-hamate hook distance (RMHD) in diagnosis of H-CTS.

DESIGN

A case-control study.

SETTING

In a tertiary medical center and a secondary hospital from Nov. 2017 to Mar. 2021.

PARTICIPANTS

Consecutive non-diabetes patients under hemodialysis were recruited and divided into a hemodialysis without CTS (H-Control) group and an H-CTS group. Age-matched volunteers without diabetes or upper extremity disorders were enrolled as the Control group.

INTERVENTION

Ultrasound examinations by two operators blinded to the patient's clinical information.

MAIN OUTCOME MEASURES

US parameters including cross-sectional area of the median nerve at the carpal tunnel inlet (CSA-I) and outlet (CSA-O), the flattening ratio of the median nerve at the inlet (FR-I) and outlet (FR-O), and RMHD.

RESULTS

Handedness and arteriovenous fistula showed no associations with CSA-I/O and FR-I/O. Compared with Control group (n=69), the CSA-I was significantly larger in the H-Control group (n=63) and H-CTS group (n=76) (p<0.05). There were no significant differences in the FR-I/-O among the three groups. For the second aim, in the H-CTS group(n=38), there was a significantly lower RMHD compared with both the Control (n=20) and H-Control groups (n=30) (0.1%±2.2% versus 3.5±2.3% and 3.8±1.7%, p<0.05). An RMHD cutoff value of <2.7% yielded a specificity of 80.0%, a sensitivity of 94.7%, and an overall accuracy of 88.2% in the diagnosis of H-CTS.

CONCLUSIONS

Neither CSA-I/-O or FR-I/-O have a role in the diagnosis of H-CTS. RMHD might be a useful US parameter in the diagnosis of CTS in non-diabetic patients undergoing hemodialysis.

Brain Structural Changes in Carpal Tunnel Syndrome Patients: From the Perspectives of Structural Connectivity and Structural Covariance Network

BACKGROUND

Carpal tunnel syndrome (CTS) is a common peripheral entrapment neuropathy. However, CTS-related changes of brain structural covariance and structural covariance networks (SCNs) patterns have not been clearly studied.

OBJECTIVE

To explore CTS-related brain changes from perspectives of structural connectivity and SCNs.

METHODS

Brain structural magnetic resonance images were acquired from 27 CTS patients and 19 healthy controls (HCs). Structural covariance and SCNs were constructed based on gray matter volume. The global network properties including clustering coefficient (Cp), characteristic path length (Lp), small-worldness index, global efficiency (Eglob), and local efficiency (Eloc) and regional network properties including degree, betweenness centrality (BC), and Eloc of a given node were calculated with graph theoretical analysis.

RESULTS

Compared with HCs, the strength of structural connectivity between the dorsal anterior insula and medial prefrontal thalamus decreased (P < .001) in CTS patients. There was no intergroup difference of area under the curve for Cp, Lp¸ Eglob, and Eloc (all P > .05). The real-world SCN of CTS patients showed a small-world topology ranging from 2% to 32%. CTS patients showed lower nodal degrees of the dorsal anterior insula and medial prefrontal thalamus, and higher Eloc of a given node and BC in the lateral occipital cortex (P < .001) and the dorsolateral middle temporal gyrus (P < .001) than HCs, respectively.

CONCLUSION

CTS had a profound impact on brain structures from perspectives of structural connectivity and SCNs.

Application of digital infrared thermography for carpal tunnel syndrome evaluation

We investigated the thermographic findings of carpal tunnel syndrome (CTS). We enrolled 304 hands with electrodiagnostically identified CTS and 88 control hands. CTS hands were assigned to duration groups (D1, < 3 months; D2, 3‒6 months; D3, 6‒12 months; D4, ≥ 12 months) and severity groups (S1, very mild; S2, mild; S3, moderate; S4, severe). The temperature difference between the median and ulnar nerve territories (ΔM-U territories) decreased as CTS duration and severity increased. Significant differences in ΔM-U territories between the D1 and D3, D1 and D4, D2 and D4, and S1 and S4 groups (P = 0.003, 0.001, 0.001, and < 0.001, respectively) were observed. Thermal anisometry increased as CTS duration and severity increased. Significant differences in thermal anisometry between the D1 and D4 as well as the D2 and D4 groups (P = 0.005 and 0.04, respectively) were noted. Thermal anisometry was higher in the S4 group than in the S1, S2, and S3 groups (P = 0.009, < 0.001, and 0.003, respectively). As CTS progresses, skin temperature tends to decrease and thermal variation tends to increase in the median nerve-innervated area. Thermographic findings reflect the physiological changes of the entrapped median nerve.

Diabetic polyneuropathy and carpal tunnel syndrome together affect hand strength, tactile sensation and dexterity in diabetes patients

AIMS/INTRODUCTION

Carpal tunnel syndrome (CTS) and diabetic polyneuropathy (DPN) can occur together, and this concomitance is thought to be higher in diabetes patients. We aimed to examine and compare hand function in type 2 diabetes mellitus patients without CTS and DPN (CTS-DPN-), patients with CTS without DPN (CTS+DPN-), patients with DPN without CTS (CTS-DPN+), and patients with CTS and DPN (CTS+DPN+).

MATERIALS AND METHODS

A total of 161 type 2 diabetes mellitus patients underwent physical examination and electrodiagnostic tests. Grip and pinch strengths, tactile sensory thresholds were measured for each participant. Purdue pegboard test was used in evaluating the hand dexterity of the participants.

RESULTS

Of the 161 type 2 diabetes mellitus participants, 36 (22.4%) had both CTS and DPN. CTS participants had lower grip (26.6 ± 10.6 vs 35.2 ± 14.3, P < 0.001) and pinch (6.3 ± 2.6 vs 7.5 ± 2.9, P = 0.026) strengths compared with non-CTS participants, whereas DPN participants had elevated tactile sensory thresholds of both the second (2.8 [2.8-3.6] vs 2.4 [2.4-2.8], P < 0.001) and the fifth (2.8 [2.8-3.6] vs 2.4 [2.4-2.8], P < 0.001) fingers compared with non-DPN participants. The CTS+DPN+ group had lower Purdue pegboard test scores than other groups. Grip (r = 0.482, 0.530, 0.467, 0.498, all P < 0.001) and pinch (r = 0.246, P = 0.003; r = 0.265, P = 0.001; r = 0.264, P = 0.001; r = 0.235, P = 0.005) strengths were positively correlated with Purdue pegboard test scores, whereas tactile sensory thresholds were negatively correlated with Purdue pegboard test scores (r = -0.447 to -0.359, all P < 0.001).

CONCLUSION

Type 2 diabetes mellitus patients with both DPN and CTS had lower grip and pinch strengths and decreased tactile sensation, both of which were correlated with poorer hand dexterity.

Ultrasonographic and electrophysiological outcomes of carpal tunnel syndrome treated with low-level laser therapy: A double-blind, prospective, randomized, sham-controlled study

Objectives

The aim of this study was to investigate the therapeutic effects of low-level laser therapy (LLLT) on clinical, ultrasonographic (US), and electrophysiological findings in carpal tunnel syndrome (CTS).

Patients and methods

Between January 2015 and August 2015, 42 patients (7 males, 35 females; mean age: 50.4±8.7 years; range, 32 to 65 years) with mild-to-moderate CTS were randomly assigned to one of two groups: active LLLT (therapy group, n=22) 0.8 J/painful point and sham LLLT groups (n=20). Both groups wore neutral wrist orthoses. The patients were evaluated before and after 15 sessions of therapy (670 nm, 4 J/session over the carpal tunnel). Follow-up parameters included the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) Symptom Severity Scale (SSS), Functional Status Scale (FSS), nerve conduction studies and US evaluation of the median nerve cross-sectional area (CSA), vascularization (via power Doppler), flattening ratio (FR), and palmar bowing of the flexor retinaculum.

Results

Nocturnal paresthesia improved in both groups; however, pain and patients with a positive Phalen’s test reduced only in the therapy group (p=0.031). The FSS and SSS scores also improved only in the therapy group (p<0.001). Electrophysiologically, median sensory nerve conduction velocities showed a significant improvement only in the therapy group (p=0.002). The CSA, FR, and vascularization of the median nerve showed a significant improvement in the therapy group alone (p<0.001, p=0.048, and p=0.021, respectively).

Conclusion

Improvements in the signs and symptoms of CTS and hand function, the improvements in sensory nerve conduction studies, and reduction in median nerve CSA, FR and vascularity in the LLLT group can be attributed to the anti-inflammatory and analgesic effects of LLLT. This study provides new US data demonstrating efficacy of LLLT along with a clinical and electrophysiological improvement. The LLLT seems to be an easily applied, non-invasive treatment option.

Molecular and Clinical Elucidation of the Mechanism of Action of Steroids in Idiopathic Carpal Tunnel Syndrome

BACKGROUND

Carpal tunnel steroid injection is a nonoperative intervention for the treatment for idiopathic carpal tunnel syndrome (CTS). The antifibrotic, anti-inflammatory, and antiedematous properties of steroids account for their therapeutic effects in the context of CTS; however, their relative contribution has not been clarified.

METHODS

Fibroblasts from subsynovial connective tissues (SSCT) were intraoperatively collected from patients with idiopathic CTS and were incubated with or without the steroid triamcinolone acetonide (TA) for 1, 3, and 7 days; the expression of fibrosis-related genes and inflammatory cytokines was evaluated using quantitative reverse transcription-polymerase chain reaction. A clinical prospective study was conducted with patients who received carpal tunnel TA injections. We performed clinical and electrophysiological evaluations before and 1, 3, and 5 months after TA injection; and we compared the median nerve, flexor tendon, and SSCT areas and the median nerve flattening ratio before and 1 month after TA injection using 3-T magnetic resonance imaging (MRI).

RESULTS

TA induced downregulation of the fibrosis-related genes Col1A1 (collagen type I alpha 1 chain), Col1A2, and Col3A1 but not the inflammation-related genes. The nerve flattening ratio did not change after TA injection according to the MRI-based observation of the median nerve, flexor tendon, and SSCT areas.

CONCLUSIONS

The therapeutic effects of injected TA are apparently mediated by its antifibrotic rather than its anti-inflammatory and antiedematous properties. TA probably alters the properties but not the morphology of SSCT.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.