Review Question - QID 218141

The presence of pantrapezial arthritis involving the scaphotrapeziotrapezoidal (STT) articulations, which defines Eaton Stage IV basilar thumb arthritis, is a contraindication to performing a CMC arthrodesis procedure in this patient.

Basilar thumb arthritis encompasses a wide range of pathology with very specific treatment indications based on the stage of disease at the time of presentation. Defined by the Eaton and Littler classification, it can be broken down into four stages, with the first involving a "pre-arthritic" joint with mild joint space widening, the second involving CMC sclerosis with osteophytes < 2mm, the third involving CMC sclerosis with osteophytes > 2mm, and the fourth involving pantrapezial arthritis inclusive of the STT joints. Stage I and II disease are typically treated conservatively but can be treated with a first metacarpal osteotomy if the CMC is not hypermobile and there is no IP hyperextension deformity exceeding 10 degrees. Most commonly, however, symptomatic patients with more advanced disease are treated with a trapeziectomy + LRTI (ligament reconstruction and tendon interposition). In patients with stage IV disease, concomitant excision of the proximal third of the trapezoid can be performed. For laborers requiring maintenance of grip strength with stage II-III disease, CMC fusion can be performed but, again, the presence of STT arthritis (stage IV disease) remains a contraindication.

Weiss et al. provide a review of basilar thumb arthritis. The authors note that the thumb basal joint is the second most common site of osteoarthritis in the hand, and osteoarthritis of this joint can contribute to painful movement and debilitating function. Though thumb basal joint arthritis can be initially managed with medications, orthoses, and steroid injections, it frequently progresses despite these interventions. They conclude that surgical management commonly consists of trapeziectomy with or without interposition or suspension, arthroplasty with implant, volar ligament reconstruction, osteotomy, or arthrodesis, with none of these techniques having been proven to be superior to the others.

Kapoutsis et al. review CMC and STT arthritis and the treatment options of arthroscopy, arthroplasty, and arthrodesis. The authors note that though arthrodesis remains the classic procedure for the heavy laborer and a good option for patients with Eaton stage III arthritis of idiopathic, rheumatic, or post-traumatic etiology, an untreated STT joint in patients with STT arthritis will produce ongoing symptoms. They also note that patients with STT arthritis may present with DISI-like midcarpal instability that could worsen after surgical intervention, leading them to suggest this instability as an additional possible cause of dissatisfaction among surgically treated patients when the STT joint is not addressed in the setting of CMC arthritis.

Eaton et al. provide an article describing their classification system as outlined above. Although the classification is useful for describing the radiographic progression of thumb CMC arthrosis, it is more of historical interest and its clinical utility may be limited, given that wide variation exists among surgeon preferences for the surgical management options of basilar thumb arthritis.

Figures A and B are PA and lateral radiographs of the hand demonstrating acute, comminuted fractures of the thumb metacarpal and the distal radius.

Incorrect Answers:
Answer 1: Chronicity of the injury does not preclude the patient from having a CMC fusion.
Answer 2: Post-traumatic arthritis would likely be an indication for, not against, CMC arthrodesis.
Answer 3: A hyperextension deformity of the IP joint is a contraindication to performing an isolated first metacarpal osteotomy, not a CMC fusion.
Answer 4: The presence of pantrapezial, not radiocarpal, arthritis is a contraindication to performing a CMC fusion due to persistent arthritis at the scaphoid articulation.