The tri-scaphe joint is formed by the articulations of the scaphoid, trapezoid and trapezium. This 'joint' is found at the base of the thumb and pain from it can be difficult sometimes to distinguish from pain arising from the joint immediately under the thumb, the first carpo-metacarpal (cmc) joint. It can also be confused with De Quervain's disease.
The presenting symptom is nearly always pain which early on may be related only to activity but later it can be there all the time. Your GP is likely to prescribe NSAIDS but other treatments include functional bracing and physiotherapy. Developing coping strategies is all part of the early attempts to live with the condition. Clearly if there is an activity that always causes the pain then it makes sense to modify the way you do that activity.
As with many chronic degenerative conditions a cortisone injection may give some relief for a variable length of time. It can be difficult to place a needle accurately into this narrow joint so I recommend that it is done under x-ray control. If the cortisone is placed absolutely accurately in the right spot then it has a better chance to work. There is considerable variation in the way the condition progresses. In many instances it goes through a nasty acute phase but then seems to settle down, not that it goes away but it may become tolerable. The ultimate option is always surgery.
The traditional operation for OA of the tri-scaphe joint has been a fusion. A number of older articles have confirmed this to be a predictable operation, however there have been some recent reports suggesting that the long-term results are not as good so now I favour an excision interpostion arthroplasty. Essentially this means cutting out the joint surfaces and interposing some soft tissue and making a new, fibrous joint. This procedure is not dissimilar to that in a trapeziumectomy. A cast is needed for six weeks after the surgery to allow the new joint to stabilise.