The Ligament Injury That Gets Called a Sprain and Ends in Arthritis
There’s a small ligament deep in your wrist holding two of the little carpal bones together, the scaphoid and the lunate. It’s a few millimetres across and it does an unreasonable amount of work.
Fall on an outstretched hand and it can tear.
The X-ray usually looks normal. The wrist is swollen and sore. It gets called a wrist sprain, and everybody goes home.
Left alone, this one has a known ending, and the ending is a wrist full of arthritis roughly a decade later. It’s the single most consequential thing hiding behind the word sprain.
What’s actually happening in there
Your wrist isn’t one joint. It’s eight small bones arranged in two rows, sliding and rotating against each other in a choreography held together entirely by short, tough ligaments.
The scaphoid and the lunate sit side by side in the first row, and they naturally want to rotate in opposite directions under load. The ligament between them is what stops that.
Tear it, and they start doing exactly what they always wanted to do. The scaphoid tips forward, the lunate tips back, and the neat spacing between the bones opens into a gap.
Now the load paths through the wrist are wrong. Cartilage that was designed to be loaded across a broad surface gets loaded on an edge instead, and it wears through at that edge over years.
The wear follows a predictable sequence that hand surgeons have mapped and named. It starts at one corner of the scaphoid, spreads across the wrist, and ends as advanced arthritis in a wrist that was “just sprained” in someone’s twenties.
(Predictable is the important word. This isn’t bad luck. It’s mechanics running their course.)
How to suspect it
The location is the first clue. Pain on the BACK of the wrist, in the middle-to-thumb side, just past the end of the forearm bone. Press along there and there’s a specific tender spot.
Then the behaviour:
- A click or a clunk with certain movements, especially rotating the wrist side to side.
- Pain and weakness specifically when loading the wrist bent backwards: push-ups, pressing up out of a chair, a plank, leaning on a counter.
- Grip that’s noticeably weaker than the other side, and painful at the end of the squeeze.
- And the giveaway: it’s still doing all of this at six weeks, when a real sprain would be long finished.
Important thing to know about the imaging: a standard X-ray often misses this. Early on, the gap only opens when the wrist is under load, so it can look perfectly normal at rest. Getting it caught frequently needs specific stress views, a clenched-fist view, or an MRI or arthroscopy.
Which means “the X-ray was normal” does not clear this injury, in exactly the same way it doesn’t clear a scaphoid fracture. Same fall, same normal X-ray, two different things that both bite you later.
Why the window is real
Caught within roughly the first six weeks, the torn ligament ends are still there and still healthy enough to be stitched back together. Repairing something that exists is a fundamentally easier operation with better results.
Months later, those ends have retracted and scarred. There is nothing left to sew. The operation becomes a reconstruction, borrowing tendon to build a substitute ligament, and reconstructions are longer, harder and less reliable than repairs.
Years later, once the arthritis has arrived, the conversation stops being about the ligament at all. It becomes about salvage: fusing part of the wrist, or removing a row of bones. Those operations work, in the sense that they reduce pain. They also permanently cost you movement.
Six weeks buys a repair. Six months buys a reconstruction. Six years buys a fusion.
What treatment actually looks like
Partial tears where the bones haven’t shifted can often be managed without surgery: a period of splinting, then a specific strengthening programme aimed at the muscles that help hold the scaphoid in position. Done properly this is genuinely effective, and it’s skilled work rather than generic wrist exercises.
Complete tears with the bones already separating are surgical, and the sooner the better for the reasons above.
Either way, recovery is long. Expect several weeks of immobilisation after surgery, then months of graded rehab, and a realistic return to full loading somewhere around six months to a year. Some permanent loss of the extremes of wrist movement is common.
The short version
A fall, pain on the back of the wrist, a click, weakness pressing up on it, and still going at six weeks: that is not a sprain, and a normal X-ray does not settle it.
Ask for proper imaging while the ligament is still repairable. This is one of the few injuries on this site where the difference between six weeks and six months is the difference between a stitch and a fusion.
Written by Nigel Chua, hand occupational therapist in practice since 2005. Tens of thousands of hands, wrists and elbows assessed and treated. My credentials are here. This article explains; it doesn’t examine. A wrist still painful and clicking at six weeks after a fall needs imaging, not more patience.