Page 51 - Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints

Introduction
Osteoarthritis (OA) of the first carpometacarpal (CMC1) joint is a very common and burdensome disease, and often co-exists with OA in the scaphotrapeziotrapezoid (STT) joint. Patients are usually treated in primary care to alleviate symptoms with nonsteroidal anti-inflammatory drugs, splints, and steroid injections. However, persistent pain or severe functional impairment are indications for surgical intervention.1
Various surgical procedures have been described to treat CMC1 OA, but no 3 optimal technique has yet been determined.2-4 Most popular are complete trapeziectomy with ligament reconstruction and tendon interposition (LRTI),5
and other types of complete trapeziectomy. The complete removal of the
trapezium can alleviate symptoms from both the CMC1 and the STT joint, but can also lead to proximal migration of the first metacarpal bone and lead to lower pinch strength.6 Therefore, other surgical procedures are often performed to avoid migration and strength reduction such as hemitrapeziectomy, resection arthroplasty, CMC arthrodesis or joint prosthesis. Each of these techniques is associated with their own benefits and risks. For example, techniques in which most of the trapezium is spared, show less migration of the first metacarpal bone, but comparable other long-term results to complete trapeziectomy.7-9 However, all these procedures have in common that the STT joint is not treated and it should therefore only be applied when this joint is not affected with OA.
Radiographical assessment is used to verify the presence of OA in the CMC1 and STT joint, and to rule out other diseases. However, evaluation of the STT joint can be difficult due to overprojection of the carpal bones. It has been reported that more than half of STT OA is missed on the radiograph,10 which might lead to selecting an improper surgical procedure.
Detection of STT OA might be improved with CT (Computed Tomography) due to its better spatial resolution. In previous studies, CT was found to be more sensitive than radiography in the detection of osteophytes and cysts in knee OA,11 and CT was better in determining the positions of bony structures and anomalies in hip OA.12
CT for detection of thumb base OA
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