Where exactly does the bone break in a wrist fracture?
The break lies almost always in the last part of the radius, a few centimetres before the wrist. The radius carries most of the load running from the hand into the forearm. In a fall onto the outstretched hand that section gives way first, and the ulna often stays whole.
The forearm has two bones. The radius lies on the thumb side, the ulna on the little-finger side. Towards the wrist the radius broadens and takes over the contact with the carpal bones. That broadened section is the weakest point in the chain: soft, spongy bone inside, a thin shell outside. «Distal» means nothing other than away from the body, so near the wrist.
If someone falls forward and catches themselves on the outstretched hand, the whole force runs in fractions of a second through the palm into the radius. The fragment usually tips upwards, towards the back of the hand. That pattern is named after the surgeon who first described it, the Colles fracture. If it tips the other way, towards the palm, it is called a Smith fracture; it is rarer and counts as less stable.
This break makes up about a fifth of all fractures in adults and about a quarter in children and adolescents. Its frequency has two reasons: the hand shoots forward by reflex before the head can think, and the bone at this point loses density over the years. So there are two peak ages, between 10 and 14 and from 60 onwards, with women affected considerably more often than men from middle age.
When is a cast used and when is surgery needed?
What decides is whether the fragments sit in a good position and stay there. A stable break without notable displacement is treated in a cast. If the break is displaced, unstable, running into the joint, or pressing on a nerve, surgery with a plate is the rule.
The limits are set out in the guideline and measured on the X-ray: how far the fragment has tipped and whether the joint surface shows a step. If everything stays within those values, a cast is the simpler and equally good solution. If the position slips in the follow-up X-rays of the first two weeks, surgery follows; that is why those checks matter.
- Conservative, in a cast: stable breaks outside the joint, slightly displaced joint fractures, and breaks that can be set well.
- Surgical, with a plate: unstable and displaced breaks, steps in the joint surface, open fractures, signs of nerve pressure alongside, and a failed attempt in a cast.
- The plate is usually placed from the palm side. It holds the break firmly enough for early movement.
- In older people and where the demands on the hand are modest, a position that looks crooked on the X-ray can still give good function.
A fall is an accident; a break without an outside event is not. Report the accident to your employer or your health insurer. For accidents covered by the employer’s compulsory accident insurance, the deductible (Franchise) and the retention fee (Selbstbehalt) do not apply. If the accident is covered through the health insurer, as for pensioners, children or people not in employment, they apply as they do for illness.
How long does the hand stay immobilised?
For a break treated in a cast it is as a rule four to six weeks. After surgery with a plate, immobilisation is shorter: often one to two weeks in a removable splint, and depending on the break an orthosis after that. Your doctor sets the exact plan.
The difference has a simple reason. In a cast the dressing itself holds the fragments together, so it has to stay until the bone carries load. The plate takes over exactly that task from the inside. It is stable enough for you to move the wrist early without losing the position.
Anyone who keeps the arm tucked against the body for weeks ends up with two problems instead of one: the wrist and a stiff shoulder. The stiff shoulder can be avoided without outside help, with the movements in the list above.
Why is the hand stiff and swollen after the cast?
Because tissue that does not move sticks, and fluid does not drain without movement. Joint capsules and tendon sheaths shorten within a few weeks and the cartilage is less well supplied. At the same time the muscle pump is missing that carries lymph and blood back out of the hand. Together that gives the thick, clumsy hand after the cast comes off.
The break itself adds to it. A broken bone injures the whole area and not the bone alone: blood vessels tear, the tissue answers with inflammation, and inflammation brings fluid. That fluid is thicker than ordinary tissue water. If it stays where it is, fibres form in it, and swelling turns into sticking.
What really helps against the swelling
- Keep the hand above heart height, several times a day and consistently while resting.
- Move the fingers: the careful fist, without pain.
- Gentle compression with an elastic glove or a finger wrap.
- Stroking towards the armpit, in the direction of the lymph nodes, with very light pressure.
- Use the hand in daily life: holding a cup or doing up buttons.
Heat and vigorous kneading are not a good idea in this phase; they increase the blood flow and with it the swelling. Cooling is allowed, but never directly on the skin and not for longer than about ten minutes at a time.
What is done in the first weeks after the cast?
First the swelling and finger movement, then the wrist, and strength last. In the first weeks after removal the hand is moved actively, not stretched and not loaded. It matters here that the finger muscles sit in the upper forearm and their tendons run straight through the injured area.
- Week one to two after removal: reduce the swelling, bend and straighten the fingers fully, move the wrist actively and without much pain. No pulling force, no pushing up. Just as important and part of occupational therapy: the upper arm and shoulder muscles should stay as relaxed as possible; medically they are not part of the injury.
- Week three to four: extend the range of wrist and forearm rotation, first everyday tasks against light resistance, scar treatment after an operation.
- From about week six after the cast came off or after the operation, once your doctor clears it: building strength, pushing up, heavier objects, and returning to work and sport in stages.
Practise the forearm rotation with the elbow tucked in: upper arm close to the body, elbow at a right angle, then turn the palm slowly up and down again. Without the elbow tucked in, the shoulder takes over and the movement looks better than it is. The same goes for bending the wrist: the forearm rests, only the hand moves.
In hand therapy this phase is less about instructing exercises than about where the progress gets stuck and why. We measure the range of movement, watch the swelling, and match the build-up of load to what you actually do at home and at work. The guideline notes that an advantage of supervised therapy over well instructed self-training has not been shown. Anyone who understands the exercises and does them reliably gets a long way alone in a straightforward case.
The exercises for home are in the patient information sheets to print out. Short sessions work best, five to ten minutes, spread several times over the day. One long session in the evening achieves less and often leaves the hand swollen again.
How long does recovery take altogether?
Most of the symptoms settle within about two months. Anyone still troubled after that can expect that six months after the break only a little pain and a little limitation remain. Until strength and fine movement are fully back, a year often passes.
That range unsettles many people because it is so wide. It has a factual reason: the patterns of break differ greatly. A clean break outside the joint in a 45-year-old runs differently from a comminuted fracture involving the joint in a 78-year-old. The movement you started with counts too, and whether the dominant hand is affected.
Progress does not come evenly. The first weeks after the cast comes off bring visible jumps, after that it gets slow, and in that slow phase many people stop the exercises. Full movement and final grip strength are usually reached only three months to a year after the injury. In some people it takes longer than a year for function to be fully back, and that too is within the normal range.
Comparing the strength of the injured hand with the other side is a usable measure, and it usually lags the movement by weeks. As long as the range of movement is still growing, the strength comparison is no cause for concern.
Which complications do I need to know about?
Three are important enough to know: complex regional pain syndrome, pressure on the median nerve in the carpal tunnel, and rupture of the long thumb extensor tendon. All three are uncommon and treatable, and with all three what counts is noticing them early.
CRPS develops in about two to five of a hundred people after a radius fracture treated in a cast. It is marked by pain too strong for the expected course of healing, along with stubborn swelling, changed skin colour and temperature, changed sweating, and a restriction of movement that does not fit the findings. Strong pain still a week after the break counts as a warning sign. Treatment includes occupational therapy, and the earlier it starts the better.
In carpal tunnel syndrome the swelling presses on the median nerve, which runs through a narrow channel at the wrist. Typical are tingling and numbness in thumb, index and middle finger, often at night. Rupture of the long thumb extensor tendon affects a small proportion of people, after cast treatment as well, and usually shows itself weeks later when the tip of the thumb can suddenly no longer be lifted. Both belong in a medical assessment.
Your doctor makes the diagnosis, never the therapy. We see the hand regularly and report back what we notice; the interpretation and the follow-up X-rays belong in the medical consultation.