Ultrasound
The median nerve shows continuity. There is nerve kink about 15 - 20 mm proximal end of the carpal tunnel. The kink nearly disappeared with finger flexion. The nerve shows mild edema proximal to the tunnel and is compressed in the distal tunnel region. Flexor retinaculum shows defect at proximal tunnel level. However, there is intact retinaculum at distal tunnel level causing nerve compression. There is no fibrosis causing nerve entrapment. There is no tenosynovitis/ mass lesion in the tunnel. The palmar cutaneous branch could not be identified. However, there was no neuroma along the expected course of the palmar cutaneous branch.
The contralateral side was examined for comparison. It shows normal flexor retinaculum covering proximal to distal tunnel without defect.