Patient Reported Outcomes Measures (PROM) in Carpal Tunnel Therapies in Patients With Inherited Neuropathies

An online survey will be used to assess outcomes in conservative and surgical therapies used for carpal tunnel syndrome (CTS) in patients with a diagnosis of inherited neuropathy such as CMT or HNPP (Charcot-Marie-Tooth disease and Hereditary Neuropathy with liability to Pressure Palsies respectively). HNPP is an inherited neuropathy which is allelic to CMT1A. This patient reported outcome measurement will also assess symptom severity and functional status related to carpal tunnel syndrome (CTS) in various types of patients with inherited neuropathy.

The survey incorporates two validated questionnaires for the evaluation of outcomes related to carpal tunnel syndrome. The Boston Carpal Tunnel Questionnaire (BCTQ) is very specific to carpal tunnel syndrome (CTS). The Disability of Arm, Shoulder and Hand (DASH) questionnaire is less specific for CTS but has been shown to have equal validity in the assessment of outcomes in CTS. The relative non-specificity of DASH for CTS can be useful in assessing the possible contribution of CMT to the overall upper extremity symptom severity and functional outcome. Data collected from participants with a diagnosis or therapies for CTS can be compared to data collected from participants with no diagnosis or therapies for CTS.

Furthermore, the study will incorporate components from the CMTNS to assess the extent of CMT disease in the participants.

It is proposed that a retrospective analysis of patients with CMT who have symptoms in the upper extremities suggestive of carpal tunnel syndrome. Two validated questionnaires exploring changes in symptoms and functional status (BCTQ and DASH) can be used in evaluating outcomes of patients with reported symptoms or diagnosis of carpal tunnel syndrome.

The Boston Carpal Tunnel Questionnaire (BCTQ) is a 19 item scale which was developed specifically for carpal tunnel syndrome and consists of 11 questions to assess symptom severity and 8 questions to assess functional status. BCTQ has established test-retest reliability with a good Pearson's correlation of scores on re-test (0.91 for the symptoms severity component and 0.93 for the functional status component of the test). High internal consistency has also been reported for the BCTQ (0.88-9.92). Convergent validity has been demonstrated with high correlation between pre- and postoperative BCTQ scores and physical measures such as grip, key pinch and three-jaw pinch. Responsiveness of the BCTQ after carpal tunnel surgery has been demonstrated in randomized clinical trial settings. BCTQ has also been reported to be 2-4 times more responsive to clinical improvement in comparison to measures of neuromuscular impairment. High response rates have been reported with BCTQ with 80-93% at 6-12 weeks follow-up and between 67-93% at 6-12 months follow-up after carpal tunnel release. Response rates remained high at 85% at 2 years follow-up. Mailed follow-up response rate of 69% has been reported with a mean follow-up of 4.8 years. The mean time to complete BCTQ has been reported to be 5.6 minutes. There is no data to indicate the precision of BCTQ in relation to carpal tunnel syndrome.