At first a hemiplegic arm is limp (Brunnstrom Stage 1). Stage 2 is exciting because stroke survivors see small limb movements. In Stage 2 my shoulder could fling my hand onto my thigh, but my hand slid off because my elbow muscles were weak. Small movements turn into a synergy (Stage 3). Synergy means muscles work together, but a stroke creates abnormal synergies that produce one movement pattern. The photo shows a version of the flexion synergy that affects the arm. There are many versions of this synergy so your movement may look different from other stroke survivors. A trait everyone shares is that to move one joint you have to move the whole limb whether you want to or not. This is exhausting. When the flexion synergy is full blown it keeps the hand fisted and the arm close to the body.
I made Stage 3 functional with help from an electrical stimulation device called NeuroMove that has a biofeedback component and a spring-loaded hand splint called SaeboFlex. These devices helped me retrain my brain to open my hand a few inches so I can receive an object from my sound hand. Hand-to-hand transfers let my hand hold objects while my sound hand manipulates them. This manual skill is useful because many basic ADLs take place close to the body.
Stage 4 makes you more functional. It brings shoulder, elbow, and forearm control that moves the hand away from the body and turns the hand palm up. The hand is still synergy-bound. This means I cannot open my hand unless I also move my shoulder and elbow. My Stage 4 skills are keeping my hand open while reaching at waist height or lower and partially rotating my forearm to orient my hand to a few different positions objects rest in. The non-dominant hand cries out because thousands of times in a life time it reaches for an object to hold it still is so the other hand can manipulate the object.
I was stunned to learn my hand is useful without reaching Stage 5 (relative independence from synergy). The Neurodevelopment Treatment approach (NDT) says the hand needs good shoulder control. This is true when you want to swing a hammer with the precision needed to hit the nail instead of your thumb. Many ADLs do not require this kind of precision. Why defer hand use when ADLs can make do with emerging arm and hand control? As an OT I knew that millions of stroke survivors have learned to walk using the extension synergy. As an NDT certified OT I was taught the flexion synergy is BAD. I had to have a stroke to see the flexion synergy that dominates the arm and hand in a more positive light.