I am haunted by a client who had her fingernails grow into her palm because the nurses could not open her tight hemiplegic (paralyzed) hand. Here are tricks that make opening a tight hand easier.
Trick # 1. Using force makes spastic muscles fight harder. The instant you feel resistance slow down so movement is barely visible. Patience pays off.
Trick # 2. Try not to touch the client's palm. This may stimulate the hand to close.
Trick # 3. To open the hand, start by bending the wrist slightly 1st. This is how police get people to open their hand to drop a weapon. Bending the wrist relaxes tendons that cross over the wrist before they go to the ends of your fingers.
Caution: Aim for a small amount of wrist flexion (see angle in photo). As the tendons relax, the fingers will open slightly so you do not have to pull on fingers curled in a tight fist.
Trick # 4. A fist will relax even further if you straighten the thumb. The thumb has half the muscles in the hand so it is a bully. The trick is to wrap several fingers around the base of the client's thumb rather than pulling with the bony ends of your fingers.
Caution: Overstretching the fingers can damage muscles needed for active movement later on (lumbricals and interossei). Always keep the fingers in a straight line with the palm.
DO NOT straighten the fingers like in the photo on the left.
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When stretching the wrist, it is better to aim for partial finger extension so muscles will relax instead of fight you. I can get my wrist all the way back now, but I always keep my fingers in line with my palm (see green arrows). homeafterstroke.blogspot.com