Sonographic follow-up after endoscopic carpal tunnel release for severe carpal tunnel syndrome: a one-year neuroanatomical prospective observational study

Changes in Cross-sectional Area of the Median Nerve and Boston Carpal Tunnel Questionnaire Scores After Carpal Tunnel Release

BACKGROUND

We hypothesized that postoperative Boston Carpal Tunnel Questionnaire (BCTQ) scores and ultrasound (US) measurements of the median nerve cross-sectional area (CSA) at the distal wrist crease are significantly decreased at 2-week, 6-week, and ≥ 6 months follow-up appointments, compared with baseline values.

METHODS

This study was a retrospective chart review of patients who presented to a single hand clinic with evidence of carpal tunnel syndrome over a 6-year period (2014-2020). Patients received baseline US measurements of the median nerve CSA as well as completion of the BCTQ, and for the patients who underwent carpal tunnel release (CTR), postoperative US measurements and questionnaire scores were obtained at 2 weeks, 6 weeks, or ≥ 6 months postoperatively.

RESULTS

This study included 224 separate wrists. Median Nerve CSA measurements were 13.2 ± 4.5 mm2 at baseline, 11.9 ± 3.6 mm2 at 2 weeks postoperatively, 11.6 ± 4.5 mm2 at 6 weeks postoperatively, and 11.7 ± 4.3 mm2 at 6 months or more (P = .002). The BCTQ Symptom Severity Scale scores were 3.14 ± 0.76 at baseline, 1.76 ± 0.63 at 2 weeks, 1.68 ± 0.70 at 6 weeks, and 1.41 ± 0.64 at 6 months or longer (P < .001). The BCTQ Functional Status Scale scores were 2.56 ± 0.89 at baseline, 2.03 ± .1.0 at 2 weeks, 1.65 ± 0.77 at 6 weeks, and 1.36 ± 0.61 at 6 months or longer (P < .001).

CONCLUSIONS

These findings demonstrated a sustained decrease in median nerve CSA and patient-reported outcomes following CTR at 2 weeks, 6 weeks, and between 6 and 12 months.

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.

Endoscopic carpal surgery in carpal tunnel syndrome: A systematic review

Objective

Endoscopic carpal tunnel release has become increasingly popular and has shown the advantage of early recovery of hand function with minimal morbidity. In this systematic review, we aimed to summarize the currently available data and describe the reported advantages and disadvantages of endoscopic carpal tunnel surgery for treating carpal tunnel syndrome.

Methods

In this study, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, which is a set of reporting requirements for systematic reviews and meta-analyses. The search strategy with MeSH terms was "MeSH (carpal tunnel syndrome) AND (endoscopic)" Filters: in the last 5 years, English-on February 27th, 2022. A total of 131 articles fulfilled the first screening criteria. A detailed analysis of those articles identified 39 that matched the criteria, of which 14 were considered appropriate for this analysis after applying the complete inclusion and exclusion criteria.

Results

A total of 14 studies met the eligibility criteria. Analysis of those studies found that all types of portals in endoscopic carpal tunnel release reduced postoperative pain at a short-term follow-up. There was no evidence to suggest the superiority of the single- or two-portal techniques in terms of outcomes. In terms of pain relief, symptom resolution, patient satisfaction, duration to return to work, and adverse events, this early use of endoscopic carpal tunnel release produced satisfactory outcomes. Further studies comparing the number of portals are needed.

Conclusion

Endoscopic carpal tunnel surgery for treating carpal tunnel syndrome is effective and both single- and dual-portal techniques provide advantages in terms of early recovery and minimal morbidity.

Nerve Echogenicity: Changes in High-Resolution Nerve Ultrasound in Carpal Tunnel Syndrome after Surgery

The aim of our prospective study was to detect changes in nerve echogenicity of the median nerve before and after successful surgery in patients with carpal tunnel syndrome (CTS) using high-resolution ultrasound. Fifteen patients with a definite diagnosis of CTS who underwent surgery were scanned by one examiner with high-resolution ultrasound, and images were analyzed by two blinded raters using ImageJ to assess the echogenicity of the median nerve (fraction of black) with a semiautomated thresholding technique before and 3 mo after surgery compared with 15 controls. In CTS patients, nerve echogenicity before surgery was significantly lower compared with that of controls (fraction of black: mean 63.9 vs. 44.6, p < 0.0001). Three months after surgery nerve echogenicity significantly increased (fraction of black was lower, mean 55.5; p < 0.0001) as a possible sign of reduction of intraneural edema, but did not reach the values of healthy controls. Semi-automated evaluation of the echogenicity of the median nerve may be used as a marker of successful carpal tunnel release. Further studies are warranted to detect how nerve echogenicity changes after unsuccessful carpal tunnel release.

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.

Usefulness of ultrasonography for diagnosing iatrogenic spinal accessory nerve palsy after lymph node needle biopsy: a case report

Background

Spinal accessory nerve (SAN) palsy is rare in clinical settings. Iatrogenicity is the most common cause, with cervical lymph node biopsy accounting for > 50% of cases. However, SAN palsy after lymph node needle biopsy is extremely rare, and the injury site is difficult to identify because of the tiny needle mark.

Case presentation

A 26-year-old woman was referred to our hospital with left neck pain and difficulty abducting and shrugging her left shoulder after left cervical lymph node needle biopsy. Five weeks earlier, a needle biopsy had been performed at the surgery clinic because of suspected histiocytic necrotizing lymphadenitis. No trace of the needle biopsy site was found on the neck, but ultrasonography (US) showed SAN swelling within the posterior cervical triangle. At 3 months after the injury, her activities of daily living had not improved. Therefore, we decided to perform a surgical intervention after receiving informed consent. We performed neurolysis because the SAN was swollen in the area consistent with the US findings, and nerve continuity was preserved. Shoulder shrugging movement improved at 1 week postoperatively, and the trapezius muscle manual muscle testing score recovered to 5 at 1 year postoperatively. The swelling diameter on US gradually decreased from 1.8 mm preoperatively to 0.9 mm at 6 months.

Conclusion

We experienced a rare case in which US was useful for iatrogenic SAN palsy. Our results suggest that preoperative US is useful for localization of SAN palsy and that postoperative US for morphological evaluation of the SAN can help assess recovery.