Dimensional changes of the carpal tunnel and the median nerve during manual mobilization of the carpal bones

A randomized clinical trial on the changing of median nerve cross-sectional area and pain after extracorporeal shock wave and low-level laser therapy added to conventional physical therapy in patients with mild-to-moderate carpal tunnel syndrome

BACKGROUND

Carpal tunnel syndrome (CTS) is the most common mononeuropathy in the upper limb. It remains uncertain whether adding extracorporeal shockwave therapy (ESWT) or low-level laser therapy (LLLT) to conventional treatment benefits CTS patients.

PURPOSE

This study aimed to compare the effectiveness of ESWT and LLLT in conjunction with conventional treatments (including carpal mobilization, transcutaneous electrical nerve stimulation, and ultrasound) on the cross-sectional area (CSA) of the median nerve and pain in mild-to-moderate CTS patients.

STUDY DESIGN

This was a single-blinded randomized clinical trial with registration number IRCT20220504054734N1.

METHODS

Thirty-six patients were randomly assigned using block balanced randomization to receive either four sessions of ESWT or 10 sessions of LLLT in addition to 10 sessions of conventional treatments over 2 weeks. Patients received numbered closed envelopes indicating their treatment group. CSA (primary) and pain (secondary) in 18 patients who completed the treatment were assessed at baseline and after 2 weeks by a blinded assessor. Paired and independent sample t-tests were used for analyses due to the normal distribution of data was checked by Kolmogorov-Smirnoff. Cohen's d effect size was used to assess the intervention's magnitude.

RESULTS

Both ESWT and LLLT groups showed significant improvements in CSA (p = 0.002) and pain (p < 0.001) from baseline to posttreatment. CSA improvement was moderate for ESWT (mean difference: 1.2, 95% CI 0.51-1.9) and mild for LLLT (mean difference: 0.76, 95% CI 0.4-1.14). Conversely, pain improvement was substantial in both groups (ESWT: mean difference 4.4, 95% CI 3.6-5.3; LLLT: mean difference 4.4, 95% CI 3.7-5.2). No substantial differences between ESWT and LLLT were observed, highlighting their comparable efficacy.

CONCLUSION

The addition of either LLLT or ESWT to conventional treatment effectively reduced pain and median nerve CSA in mild-to-moderate CTS. The absence of significant differences between ESWT and LLLT indicates their comparable efficacy in pain relief and CSA reduction.

Normative Reference Values of the Tibial Nerve in Healthy Individuals Using Ultrasonography: A Systematic Review and Meta-Analysis

BACKGROUND

High-resolution ultrasound of the tibial nerve has been used for screening of several neurologic disorders, but normative reference values of tibial nerve cross-sectional areas (CSA) have not been well established. Thus, the present meta-analysis was performed to generate normative estimates of tibial nerve CSA at various sites of the lower limb based on ultrasonography.

METHODS

Google Scholar, Scopus and PubMed were searched for potential studies. Studies were required to report tibial nerve CSA in healthy individuals to be included. A random-effect meta-analysis was performed to calculate tibial nerve CSA values. Subgroup and statistical analyses were performed to study covariates.

RESULTS

Forty-eight eligible articles consisting of 2695 limbs were included. The average tibial nerve CSA was found to be 10.9 mm2 at the ankle (95% CI: 9.9-11.8) and should not exceed 11.8 mm2 in healthy adults. At the popliteal fossa, the overall CSA was 21.7 mm2 (95% CI: 17.5-25.8) in healthy adults. At both sites, the average tibial nerve CSA was significantly larger in adults than in children, and the differences by geographical region were not statistically significant. At the ankle, tibial nerve CSA increased with age and body mass index, while at the popliteal fossa it increased with age and weight.

CONCLUSIONS

our findings indicate that the tibial nerve varied not only along its course but also among sub-variables. Establishing normal references values of tibial nerve CSA is helpful to differentiate healthy from diseased tibial nerves such as in diabetic peripheral neuropathy or tarsal tunnel syndrome.

Carpal tunnel mechanics and its relevance to carpal tunnel syndrome

The carpal tunnel is an elaborate biomechanical structure whose pathomechanics plays an essential role in the development of carpal tunnel syndrome. The purpose of this article is to review the movement related biomechanics of the carpal tunnel together with its anatomical and morphological features, and to describe the pathomechanics and pathophysiology associated with carpal tunnel syndrome. Topics of discussion include biomechanics of the median nerve, flexor tendons, subsynovial tissue, transverse carpal ligament, carpal tunnel pressure, and morphological properties, as well as mechanisms for biomechanical improvement and physiological restoration. It is our hope that the biomechanical knowledge of the carpal tunnel will improve the understanding and management of carpal tunnel syndrome.

Cross-sectional changes of the distal carpal tunnel with simulated carpal bone rotation

This study simulated the cross-sectional changes in the distal carpal tunnel resulting from inward rotations of the hamate and trapezium. Rotations which decreased the carpal arch width, increased the carpal arch area. For example, simultaneous rotation of 5 degrees around the hamate and trapezium centroids decreased the carpal arch width by 1.69 ± 0.17 mm and increased the carpal arch area by 6.83 ± 0.68 mm2. Although the bone arch area decreased, decompression of the median nerve would likely occur due to the adjacent location of the nerve near the transverse carpal ligament.

Independent risk factors of carpal tunnel syndrome: Assessment of body mass index, hand, wrist and finger anthropometric measurements

BACKGROUND: The most prevalent neuropathy in the upper extremity is carpal tunnel syndrome (CTS). A variety of related risk factors such as biomechanical exposures, body mass index (BMI), sex and hand shape are reported to be related to CTS. OBJECTIVE: We aimed to identify the role of BMI, hand, wrist and finger anthropometric dimensions in the development of CTS, and to compare these measured variables between control and CTS participants. METHODS: A cross-sectional, case control study (n = 240, CTS = 120, controls = 120) with participants recruited from a convenience sample diagnosed with CTS and referred for anthropometric measurements. The control participants were matched by age and sex. The body height, weight, hand width, hand length, wrist depth, wrist width, wrist circumference, and finger length were measured. Hand, wrist and finger indices, hand to height ratio, and BMI were calculated. Mean values of all dimensions were compared between cases and controls, and the role of independent risk factors were determined by logistic regression analysis. RESULTS: The mean BMI, age, weight, sex and height were not significant between the two groups. Among the measured dimensions and calculated indices the significantly different variables between two groups were the wrist width, wrist depth, wrist circumference, hand index, hand to height index, and wrist index. Regression analysis showed that the wrist index (β=-1.7, p = 0.0001), wrist depth (β=0.25, p = 0.0001) and wrist width (β=0.21, p = 0.0001) were the strongest factors in CTS development in the sample. CONCLUSION: Wrist parameters have a strong role in predicting the development of CTS, while BMI was not confirmed as an independent risk factor.

Diacutaneous Fibrolysis Intervention in Patients with Mild to Moderate Carpal Tunnel Syndrome May Avoid Severe Cases in Elderly: A Randomized Controlled Trial

BACKGROUND

Carpal Tunnel Syndrome (CTS) mainly affects adults of working age. The prevalence of severe cases is higher in elderly patients (>65 years old). Clinical guidelines recommend conservative treatment as the best option in the initial stages of CTS to avoid severe cases. Diacutaneous Fibrolysis (DF) has demonstrated to improve nerve conduction studies and mechanosensitivity. The main purpose was to quantify changes in the cross-sectional area (CSA) of the median nerve, transversal carpal ligament (TCL) thickness, numbness intensity, and the subjective assessment of clinical change after DF treatment in patients with CTS.

METHODS

a double-blind, randomized, placebo-controlled trial was designed. A number of 44 patients (60 wrists) with CTS were randomized to the DF group or the sham group. CSA and TCL thickness variables were registered by ultrasound. Clinical variables were assessed by the visual analogue scale and GROC scale. SPSS version 24.0 for MAC was used for statistical analysis. The group by time interaction between groups was analyzed using two-way repeated measures analysis of variance.

RESULTS

The DF group reduced CSA with a mean of 0.45 mm² (IC 95% 0.05 to 0.86) and TCL thickness with a mean reduction of 0.4 mm (IC 95% 0.6 to 2.1) compared to the sham group (p < 0.01, p < 0,03, respectively). Additionally, the DF group decreased the numbness intensity with a mean reduction of 3.47 (IC 95% 2.50 to 4.44, p < 0.01) and showed a statistically significant improvement on the GROC scale (p < 0.01).

CONCLUSIONS

DF treatment may significantly reduce CSA and TCL thickness, numbness intensity, and improved clinical perspective. DF applied in patients with mild to moderate CTS may prevent the progression of the disease as they age.

Sonographic Diagnosis of Carpal Tunnel Syndrome

Diagnostic ultrasound in the diagnosis of carpal tunnel syndrome is firmly established. Preoperative evaluation is based on quantitative parameters such as measurement of the pathologically enlarged cross-sectional area of the nerve. The value of postoperative ultrasound lies in the visualization of the anatomy and the conclusions that can be drawn from it. It focuses on the semiquantitative sonographic parameters of nerve compression. Nerve lesions and persistent strictures can be visualized and clearly localized. In recurrent disease, the primary focus is to dynamically exclude postoperative scarring, which results in a reduction of nerve gliding.

Median Nerve's Microcirculation in Carpal Tunnel Syndrome: Superb Microvascular Imaging

BACKGROUND

The objectivity of physical and electrodiagnostic tests is limited in detecting carpal tunnel syndrome and its recurrence. Predicting the median nerve blood supply using superb microvascular imaging will allow exact diagnosis and a good follow-up system. The aims of this study include using superb microvascular imaging to correlate with electromyographic diagnosis, and to determine the impact of surgery on improvement in superb microvascular imaging.

METHODS

Between July of 2019 and January of 2020, 32 wrists of 21 patients were evaluated prospectively. After preoperative electrodiagnostic studies and vascular index measurement with superb microvascular imaging, open carpal tunnel release was performed by a single surgeon, and 3 months later standardized superb microvascular imaging was performed. Preoperative vascular indexes were compared with the mild, moderate, and severe electrodiagnostic study results. Preoperative and postoperative vascular index results were compared.

RESULTS

The average of the preoperative and postoperative imaging groups was 2.77 and 1.48, respectively, and there was a statistically significant difference between the two groups (p < 0.05). Although no significant difference was found between preoperative and postoperative vascular index values in patients presenting with mild carpal tunnel syndrome (p > 0.05), there was a significant decrease in vascular index values in patients presenting with moderate and severe carpal tunnel syndrome after surgical decompression.

CONCLUSIONS

Superb microvascular imaging is emerging as a groundbreaking, new, and reliable technique. Evaluation of the median nerve blood supply is a reliable method that would be helpful for early diagnosis, planning treatment, determining the severity of carpal tunnel syndrome, and postoperative follow-up.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, IV.

Effectiveness of Conservative Treatment According to Severity and Systemic Disease in Carpal Tunnel Syndrome: A Systematic Review

(1) Background: Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy in the upper extremity. Conservative treatment has been effective for mild and moderate idiopathic CTS. However, severe CTS and systemic conditions were an exclusion criterion from the studies. The aim of this study is to review the effectiveness of conservative treatment in patients with CTS regardless of the level of severity and the presence or not of systemic diseases in the last ten years. (2) Methods: Randomized controlled clinical trials that compared the effect of conservative treatment on the Boston questionnaire and pain were selected. PubMed, PEDro, Scopus, Cochrane, and Web of Science databases were used. PRISMA statement checklist was performed. (3) Results: 876 studies were recorded, 29 were selected. Pharmacology, Electrotherapy and Manual Therapy had benefits for CTS. Electrotherapy and manual therapy could be effective for severe CTS patients with a systemic condition in the short term, but there was a low percentage of these patients included in the studies. (4) Conclusion: Some pharmacological treatments, manual therapy and electrotherapy have shown benefits for handling CTS, although the most effective combination of techniques is unknown. It would be necessary to include patients with systemic conditions in the selection criteria for future studies.

Dimensional changes of the carpal tunnel and median nerve during manual mobilization of the carpal bones - Anatomical study

STUDY DESIGN

Cross-sectional study.

BACKGROUND

The carpal tunnel is a clinically important fibro-osseous conduit for the median nerve and associated tendons. It is mechanically dynamic and therapeutic manual techniques that appear to move and change tunnel shape is part of clinical practice.

OBJECTIVES

To measure changes in dimensions of the carpal tunnel and median nerve with manual mobilization of the carpal bones in cadavers.

METHODS

A total of 20 cryopreserved upper extremities from cadaveric specimens were used in the study. The wrist was cut using an anatomical saw at the level of the pisiform. Measurements of the cross-sectional area (CSA), anteroposterior diameter (APD), transverse diameter (TD), perimeter, flattening ratio and circularity of the carpal tunnel and of the median nerve, were taken, both in the anatomical position of the wrist and during the mobilization technique of the carpal bones.

RESULTS

During the mobilization technique, the tunnel CSA (p < 0.011), APD (p < 0.001) and circularity (p < 0.001) significantly increased, while TD (p < 0.001), perimeter (p < 0.004) and flattening ratio (p < 0.001), decreased. The median nerve showed similar behavioral tendencies to the tunnel but only the CSA (p < 0.005), APD (p < 0.005) and flattening ratio (p < 0.004) of the nerve showed significant differences.

CONCLUSION

Application of external manually applied compressive force across the wrist can increase the CSA of the carpal tunnel and the median nerve in cadavers. These results are consistent with other studies in which similar results were found non-invasively using ultrasound.