Here's a neat little exercise I used with a young female gymnast who experienced pain with handstands and back handsprings. While she had a multitude of physical impairments contributing to her condition, her BIGGEST movement fault was her handstand/back handspring elbow and neck position. She frequently landed with a locked and HYPEREXTENDED elbow, reproducing her bilateral elbow pain. Furthermore, she had a tendency to crank her neck into extreme EXTENSION during handstand holds in practice, which reproduced her bilateral neck and forearm pain.
The movement fault of landing in and holding a hyperextended elbow position leads to increased compressive forces through her joint. While joint stresses are not unavoidable in gymnastics, they can definitely be reduced - especially in practice and training. The movement fault of maintaining cervical extension during her handstands closes down the intervertebral foramen in her cervical spine. The nerve roots run through here, and constantly clamping down on the nerves most likely led to irritation.
So we fixed both movement faults with this ONE DRILL. First, I show landing in an extended elbow position (bad). Next, I show landing in a FLEXED elbow position and ATTENUATING THE FORCES through my triceps, not my joint. Second, we taught her to maintain a neutral spine (+ chin tuck) during the exercise. We were able to load up the reformer with the right amount of weight to 1) prevent her joint compression pain, 2) retrain an optimal movement pattern and 3) give her options to still do handstands at practice (she's a competitive gymnast and wasn't taking "no more practice/competing" for an answer).
If you were wondering, my diagnosis for her was bilateral TOS with bilateral humeral-ulnar compression. For treatment, we also worked on her lower cervical and upper thoracic joint mobility, entrapment sites in her flexor carpi ulnaris and pec minor, and ulnar nerve tensioners. We progressed from a handstand pike up position off a table, working on the movements listed above, and eventually progressed to full handstands pain free.