Why do things fall out of my hand?
Things fall out of the hand for three different reasons. The muscle can be too weak, the grip can give way involuntarily because of pain, or the sensation in the fingertips no longer reports how firmly you are holding on. Which of the three it is decides the assessment.
Gripping is not pure strength. The fingertips report continuously whether something is starting to slip, and the grip tightens imperceptibly. If that feedback fails, you grip too loosely and the glass slips out, although the strength would be there.
The second route is pain inhibition. An irritated joint holds back the muscles that move it, without your being able to steer that; the strength is then not lost but locked.
The third route is real weakness: the nerve no longer arrives, or the muscle has become smaller. Only this route leaves a visible trace, and only it is the reason why a loss of strength belongs in an examination before it is trained.
What separates loss of strength with muscle wasting from one without?
A muscle that becomes thinner has either lost its nerve or is no longer being used. Visible wasting means that nerve fibres have already been damaged. Loss of strength without any wasting speaks more for pain, inhibition or a fresh irritation, and is far more reversible.
A muscle lives from its nerve. If the connection is pressed for a long time, fibres are lost and the muscle shrinks. Until then the damage stays reversible. Once the wasting is visible, part of it is often not recovered.
Where you can see the difference
- Ball of the thumb: the pad below the thumb. If it becomes flatter than on the other side, that speaks for the median nerve.
- Back of the hand: if the spaces between the metacarpal bones sink in, especially the one between thumb and index finger, that speaks for the ulnar nerve.
- Ball of the little finger: the pad on the outer edge, again the ulnar nerve.
Compare both hands side by side in daylight. It is notable when the hand used more is the weaker one.
That is why the distinction counts: loss of strength without wasting is usually a matter of training or of pain, provided it is not increasing. Loss of strength with wasting is a question for medicine, and one with a deadline. For a narrowed ulnar nerve at the elbow, the guideline recommends surgery as soon as deficits and muscle wasting are present.
Which nerve narrowings make the hand weak?
Two narrowings make the hand weak. The median nerve in the carpal tunnel at the wrist supplies muscles of the thumb pad; if it fails, the pad becomes flat and the thumb no longer reaches the tip of the little finger cleanly. The ulnar nerve in the groove at the elbow supplies the small muscles between the metacarpal bones.
In carpal tunnel syndrome the weakness comes late. First it tingles at night in thumb, index and middle finger, often over months. Only when the pressure persists do the fibres to the thumb pad muscles suffer, the ones that move the thumb away and bring it across. Then the grip around a bottle fails.
With the ulnar nerve in the groove at the elbow, strength often suffers early. The small hand muscles that spread the fingers are affected, and the muscle that presses the thumb against the index finger. So a sheet of paper slips away between thumb and index finger, and the thumb buckles.
Which fingers tingle assigns the cause long before strength is missing. Which pattern points to which nerve is set out in the article on the hand falling asleep; on splint and surgery in the article on carpal tunnel syndrome.
A narrowing is confirmed by measuring nerve conduction. With a short duration of illness it can be normal although symptoms exist. A normal result therefore does not rule a narrowing out.
Can pain alone make the hand weak?
Yes. A painful joint holds back the muscles that move it, without any doing of yours. The strength is then not lost but locked. Typical is a loss of strength that comes and goes with the pain, shows equally thick muscles on both sides, and improves quickly after the pain is treated.
Most often osteoarthritis lies behind it, especially at the thumb base joint. It carries every firm grip. If it hurts, the pinch grip falls away, meaning the bringing together of thumb and index fingertip, long before a muscle becomes thinner. What helps is set out under finger osteoarthritis.
Tendons give a different picture. An irritated tendon sheath at the thumb weakens the grip through the pain. A trigger finger locks and snaps rather than becoming weaker.
A ruptured tendon looks different again: one single movement no longer works at all, not merely more weakly. If a finger can no longer be actively straightened while staying passively mobile, that belongs quickly with hand surgery. More on this under tendon injury of the hand.
How much strength is lost through immobilisation and through age?
After immobilisation, strength is lost faster than muscle mass. A review of the immobilised upper limb found about three to five per cent less muscle mass after around three weeks, but close to twenty per cent less strength. The certainty of these figures is low, but the direction is clear.
The gap between the two figures is the good news. A large part of the loss after a cast or a splint is not lost muscle substance but lost control: the nervous system has unlearned switching many fibres on at once. That share comes back quickly as soon as the hand is loaded again.
What the build-up looks like after a fracture is set out under wrist fracture, and the build-up after an operation under hand therapy after surgery.
Loss of strength in later life: sarcopenia
Muscle mass and strength decline slowly from middle age. If daily life suffers from it, this is called sarcopenia. The European working group on it sets the threshold at hand strength: below 27 kilograms in men, below 16 in women.
- Standing up from a chair five times without using the arms: 15 seconds or more counts as notable.
- A walking speed of 0.8 metres per second or less speaks for a severe form.
- What is recommended is strength training and around 1.2 grams of protein per kilogram of body weight a day.
Sarcopenia affects the whole body, not the hand alone. Someone who stands up with difficulty and walks more slowly usually does not have a pure hand problem, and someone with trouble in one hand only is more likely to have another cause.
When does an illness of the whole body lie behind it?
When both hands weaken at the same time, when legs, shoulders or swallowing are affected too, or when the weakness increases over days. Then the cause is sought not in the hand but in the nervous system or in an illness of the whole body, such as the thyroid or a rheumatic disease.
Neurologically, much comes into question. After a stroke one side of the body is affected and the weakness begins abruptly; that is the subject of the article after a stroke. A polyneuropathy weakens both sides and usually begins at the feet. A narrowing of the spinal canal at the cervical spine can cause clumsy hands and an unsteady gait.
Two findings point to damage of the motor nerve cells: muscle wasting, and visible twitching of single muscle bundles under the skin. If both appear and the weakness spreads, that belongs quickly in a neurological assessment.
Weakness that increases with repetition and improves again after rest is a pattern of its own. It speaks for a disturbed transmission from nerve to muscle.
Thyroid, rheumatism and medication
- Both an underactive and an overactive thyroid can cause muscle weakness; the underactive one also favours carpal tunnel syndrome. A blood test shows both.
- In rheumatoid arthritis grip strength is often markedly reduced, partly through pain and swelling, partly through damaged joints. Morning stiffness lasting over an hour and involvement on both sides are clues.
- If a weakness fits with a new medicine, have it assessed as promptly as possible, and do not stop the medicine on your own.
At the appointment, how much weaker the hand became counts for less than over what period. A weakness since yesterday and one of five years lead to quite different investigations.
How is grip strength measured, and what does training achieve?
It is measured with a hand dynamometer: sitting, elbow bent at ninety degrees, upper arm at the body, three attempts per hand, best value counts. Training the hand works, but more slowly and more modestly than widespread grip exercises promise. Reckon in months, not weeks.
What carries meaning is less the single number than the comparison of the two hands and of the same hand over time. For that, the position has to be the same every time. Grip strength is popular because it is quick and gives a single number. In a study with around 140,000 participants it was more strongly linked with mortality than the upper blood pressure value.
So hand therapy rarely measures only the coarse grip. Pinch grip and key grip come with it, in which the thumb presses against the side of the index finger, because these are exactly the ones that fall away first with damage to the median or ulnar nerve. The value at the start serves as the reference point for the course.
The largest study on training, an exercise programme in rheumatoid arthritis, needed a daily home programme over months and showed more coarse grip strength after four months and more pinch grip strength after twelve. The difference in hand function was statistically clear but modest in size, and after a good two years it had become smaller without disappearing.
Where training is the wrong answer
- With visible muscle wasting. A muscle without a working nerve does not get thicker through practice, and the time in which taking pressure off the nerve would help is passing.
- With a weakness that increases over weeks. Progression is a reason to assess, not to train.
- With a movement that is missing entirely. Behind that lies a ruptured tendon or a failed nerve.
- With severe pain during the exercise. Then the cause of the pain is treated first.
A large area remains in which practice is right: after immobilisation, after an operation, with osteoarthritis, with strength declining in later life. Our hand therapy builds that up in measured steps; appointments through the booking page.