- •Intra- and interrater reliability and known-group validity of cross-sectional area (CSA) measurements of the median nerve taken at the carpal tunnel inlet are consistently well-supported in the literature.
- •There is conflicting evidence on the concurrent validity of measures of median nerve CSA taken at the carpal tunnel inlet when electrodiagnostic studies are used as the reference standard.
- •The findings of this scoping review indicate a 3.1%-37% false negative rate and a 0-32.1% false positive rate when diagnosing carpal tunnel syndrome, using inlet CSA cutoff values between 8.5 mm2 to 12.6 mm2.
- •In comparing data on inlet and outlet CSA measurements, there is more evidence to support the use of measuring CSA at the carpal tunnel inlet. The diagnostic utility values including sensitivity, specificity, and positive and negative likelihood ratios were consistently less for outlet CSA when compared to inlet CSA.
- •There is conflicting evidence on known-group validity of the flattening ratio when measured at the level of the hamate.
Level of Evidence
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JHT Read for Credit
Quiz: # 844
- # 1.The design of the study is.
- a.prospective cohort
- b.case series
- c.systematic review
- # 2.Study scores were
- a.reached through a consensus of the team after discussion
- b.validated by computer analysis
- c.randomly reviewed by team members
- d.dictated by pre-established norms
- # 3.CSA of the median nerve was shown to have
- a.excellent sensitivity, but poor specificity
- b.little clinical value
- c.excellent correlation to the CSA of the ulnar nerve
- d.good intrarater reliability and excellent interrater reliability
- # 4.CSA measures were taken at the
- a.midpalmar level
- b.the level of the distal wrist crease
- c.carpal tunnel inlet
- d.carpal tunnel outlet
- # 5.The evidence is that ultrasound should replace EMG & NCV in the evaluation of CTS
The authors have no disclosures.