Somehow it’s another week and another woe. This time my cmc joint fusion which was done March 2023 so it’s 18 months old.

What is Extensor Carpi Ulnaris? 

(ECU) Subsheath Rupture.  Tendons are strong, fibrous tissues that connect muscles to bones. They glide through a tunnel, or sheath, when muscles contract. The extensor carpi ulnaris (ECU) is a major tendon which connects the forearm to the wrist. This is located on the ulnar side (small finger side) of the forearm, the ECU tendon runs from the elbow to the top of the ulna bone, where it’s held in place at the base of the small finger by the ECU tendon subsheath. A sudden twisting of the wrist can cause the subsheath to rupture, allowing the tendon to snap in and out of place

Bizarrely I’ve noticed it’s also making the inner elbow bone tender to finger touch. Are they connected? Same tendon perhaps?

Pain in the inner elbow can be caused by a number of conditions, including golfer’s elbow and ECU subluxation:

Golfer’s elbow
Also known as medial epicondylitis, this condition causes pain in the inner elbow from damage to the tendons that bend the wrist. The pain is usually felt where the tendons attach to the bony bump on the inside of the elbow. It can be caused by repetitive actions like lifting weights or throwing a ball. Symptoms include pain, tenderness, stiffness, weakness, numbness, or tingling.

ECU subluxation
This condition occurs when the sheath of the Extensor Carpi Ulnaris (ECU) tendon is trapped between the radius and ulna. The ECU is a muscle and tendon that runs along the outside of the upper hand. It’s often caused by movements and strain from tennis or golf, or trauma to the lower forearm.