RESUMEN
OBJECTIVE: Patients with congenital thenar hypoplasia (Cavanagh syndrome) may undergo surgical intervention with a mistaken diagnosis of severe carpal tunnel syndrome. Conversely, patients with Cavanagh syndrome can develop co-morbid median nerve entrapment at the carpal tunnel later in life and may go untreated. This study is aimed at evaluating the role of ultrasonography in confirming/ruling out median nerve entrapment at the carpal tunnel in patients with Cavanagh syndrome. METHODS: 6 patients with Cavanagh syndrome were identified during a 10-year period from among patients referred for preoperative electrodiagnostic confirmation of carpal tunnel syndrome. All patients underwent ultrasound imaging as well as electrodiagnostic studies including motor conduction study of the median nerve with recording electrodes over the lumbrical muscles. RESULTS: Age range of patients was 39-76. The right hand was affected in 5 and left hand in 1 patient. Electrodiagnostic studies (EDX) confirmed carpal tunnel syndrome in 4 of the 6 patients. In one patient the nerve conduction studies were non-diagnostic due to absence of compound muscle action potential (CMAP) over the thenar, and the 2nd lumbrical muscles and absent sensory nerve action potentials (SNAP). Ultrasound images confirmed entrapment of median nerve at the carpal tunnel in all 5 patients. The sixth patient was mistakenly diagnosed with severe carpal tunnel syndrome by the referring physician, based on the thenar atrophy; the median nerve was normal in both ultrasound and electrodiagnostic studies. CONCLUSION: Ultrasound was useful for confirming/ruling out comorbid carpal tunnel syndrome in all 6 patients with Cavanagh syndrome. SIGNIFICANCE: Ultrasound complements electrodiagnostic study findings in patients with congenital thenar hypoplasia and comorbid carpal tunnel syndrome. It is even more valuable when EDX findings are non-diagnostic due to absent CMAP and SNAP.
RESUMEN
Asymmetric crying face (ACF) is a minor congenital anomaly that is often associated with a high rate of major malformations and may be considered an indication of a syndromic clinical presentation. Here, we report a 21-month-old male presenting with left- sided ACF, thenar hypoplasia, and esophageal atresia. Ultrasonographic images of the volar surface of the left hand evidenced the absence of muscle tissue around the thenar prominence at the level of the first metacarpal bone. No pathogenic copy number variation was detected on array-comparative genomic hybridization analysis (CGH). The association of esophageal atresia, thenar hypoplasia, and ACF has not been reported before. We discuss the possibility of a distinct association or of a sequence of anomalies associated with ACF.