Thumb Carpometacarpal Instability

Abstract

The basal joint complex of the thumb provides the framework necessary for function of the human hand. Although its unique saddle articulation allows for a wide range of motion necessary for routine function of the hand, it is rendered inherently unstable because of poor bony congruency and reliance on its capsuloligamentous support. Painful instability of this joint can stem from several causes including traumatic dislocation, various hypermobility conditions, and chronic overuse and microtrauma. A thorough history and examination as well adequate imaging is necessary for proper evaluation of instability. Treatment options range from nonoperative modalities to surgery, which entails closed, percutaneous, or open reduction with numerous ligament repair and reconstruction techniques. Arthroscopy can also serve to be a useful adjunct for assessment of the joint and stabilization of the critical capsuloligamentous structures. This review outlines the critical osseous and soft-tissue anatomy surrounding the thumb carpometacarpal joint, the key points in evaluating patients presenting with acute traumatic and chronic thumb carpometacarpal instability without fracture or arthritis, and reviews both nonoperative and operative treatments of this injury.

Radiological Influencing Factors in the Diagnosis of Painful Habitual Instability of the Thumb Basal Joint as a Precursor of Carpometacarpal Arthritis of the Thumb—A Retrospective Study

“…A high number of patients develop these symptoms at a young age. They are associated with genetic abnormalities that lead to general hyperlaxity of the connective tissue and hypermobility of the joints [ 5 , 10 , 15 ].…”

Allogeneic Tendon Ball Tamponade With The Proximal Joint Surface Of Trapezium Preservation For Treatment Of The First Carpometacarpal Joint Arthritis: A Retrospective Study

“…However, its glenoid fossa is too shallow to maintain its bony structure stability 2 . Its extensive function and special structure often leads to overuse of the rst carpometacarpal joint and ultimately leads to osteoarthritis 3,4 . The rst carpometacarpal arthritis mostly occurs in postmenopausal women.…”

Thumb Carpometacarpal Stabilization With a Dorsal Capsule Repair Augmented With an Internal Brace

“…3 If left unaddressed, repeated abnormal joint loading can result in the development of synovitis, metacarpal subluxation, cartilage injury, and ultimately arthritis. [4][5][6][7] Historically, surgical treatment of CMC instability involved grafting a strip of the flexor carpi radialis (FCR) through the first metacarpal bone, and around the abductor pollicis longus and FCR. Known as the Eaton-Littler procedure, 8 this technique emphasizes augmentation of the anterior oblique ligament of the thumb.…”

“…[9][10][11] In response, novel surgical techniques have been pioneered focusing on dorsoradial ligament reconstruction and augmentation. Dorsoradial ligament repair involving imbrication of the ligament with suture anchors and suture tape internal brace construction is being performed to treat CMC instability, 7 but there is a paucity of reported outcomes involving use of the internal brace at this location.…”

“…The amount of force measured at the CMC joint with pinch is 12 times higher than at the index/thumb tips 3 . If left unaddressed, repeated abnormal joint loading can result in the development of synovitis, metacarpal subluxation, cartilage injury, and ultimately arthritis 4–7 …”