Steroid injection for carpal tunnel with different nerve shapes

Carpal tunnel syndrome is a common condition that causes pain, numbness, and weakness in your hand. This trial is testing whether a steroid injection called betamethasone, guided by ultrasound imaging, works equally well for everyone—or whether it works differently depending on whether the median nerve (the nerve affected in carpal tunnel) has an unusual branching pattern. The study will compare results between patients whose nerves have this variation and those whose nerves have a typical shape.

Some people have a naturally different shape to the median nerve in their wrist, and doctors want to know if this medication works the same way for everyone, or if certain nerve shapes affect how well the treatment works.