Subluxed carpal bone

There are several small bones at the base of the hand that together are called the carpus – and each individual bone is a carpal bone.  That part of the wrist needs to be nice and loose to allow the hand to function and occasionally one of the bones just slightly moves out of place, i.e. becomes subluxed.  It is usually the bone in the middle of the carpus, known as the capitate, that subluxes and it appears as a bump at the back of the wrist with the hand in the dropped position.  It can happen after a sudden jolt on the outstretched hand such as in gymnastics or landing against the wall whilst playing squash.

The patient will complain of discomfort at the back of the wrist which will increase on stretching the hand downwards, with a painful block to the movement on bending the wrist upwards.

Physiotherapy can help by applying a specific technique that stretches the carpus to allow more room for the bones to move, before applying a quick thrust to the bone to put it back into place.  The technique is not painful and the result can be immediate.  Ultrasound and specific massage to the ligaments that support the bone in place can be applied if the area remains sore but this usually settles in a few days without further treatment.

Occasionally, if the joint has been out of place for several weeks or months, mobilisations may be needed to gain more movement before the technique can be applied.  The problem may recur several times but usually settles after a year or two in all.