Reliability of Metacarpal Subsidence Measurements after Thumb Carpometacarpal Joint Arthroplasty

Abstract

Measuring trapezial space is an important diagnostic tool to assess postoperative changes in thumb length. The trapezial space indexed to the capitate height method (novel) provides a simple and similarly reliable method for calculating the trapezial space ratio on a PA radiograph of the hand/wrist when other measurement techniques are unavailable and when the thumb metacarpal or proximal phalanx is not intact. The authors found a high degree of reproducibility and inter- and intraobserver reliability as measured by the ICC and the 95% limits of agreement that compare with previous agreements in the literature.

Trapeziectomy and Suture-Button Suspensionplasty for Basilar Thumb Arthritis: Is It Enough to Prevent First Ray Subsidence?

“…12 This phenomenon is not true for trapeziectomy alone or even LRTI with FCR tendon, showing the superiority of the SBS technique. 22,26 Furthermore, there is some evidence that a good outcome is reached, in terms of strength and range of motion, as long as the metacarpal subsidence is not complete and there is not a Z-deformity of the thumb. 12 Regarding function, we had a mean QuickDASH of 32 points, which is a functional score meaning that most of our patients were able to do their activities of daily living without impairment.…”

“…5,9,12 Trapezial space preservation is thought to be crucial for thumb strength, preventing thumb instability, collapse, and consequently, pain in a newly formed metacarpal-scaphoid joint. 2,25,26 Some studies show that comparing 6 weeks, 12 weeks, and 1 year postoperatively radiographs, there is no change in TSH with suture-button systems. 22 Since these results are sustained over time, an increase in strength is expected with a longer follow-up.…”

“…5 9 12 Trapezial space preservation is thought to be crucial for thumb strength, preventing thumb instability, collapse, and consequently, pain in a newly formed metacarpal–scaphoid joint. 2 25 26…”

Outcomes and recommendations for revision of thumb carpometacarpal resection arthroplasty

“…An anteroposterior radiograph of the affected hand was taken for all patients at follow-up. To quantify thumb MC subsidence, the trapezial space ratio was calculated according to Miller et al. (2018), which is known to be a reliable measurement.…”

“…An anteroposterior radiograph of the affected hand was taken for all patients at follow-up. To quantify thumb MC subsidence, the trapezial space ratio was calculated according to Miller et al (2018), which is known to be a reliable measurement. This ratio is equal to the distance between the scaphoid and the base of the thumb MC divided by the capitate height (Figure 1) or the first MC length, when the capitate height was not completely seen on the radiograph.…”