# Three-dimensional motion analysis of the thumb after trapeziometacarpal joint surgery

## TL;DR

This study uses 3D motion analysis to compare thumb movement after different surgeries for trapeziometacarpal joint osteoarthritis.

## Contribution

It introduces 3D motion capture to evaluate post-surgical thumb kinematics during daily activities and basic motions.

## Key findings

- LRTI surgery led to altered thumb movements, especially in combined motions like opposition or circumduction.
- Osteotomy and arthroplasty preserved a greater range of motion compared to LRTI.
- Daily activities showed similar TMC joint motion across groups but different adjacent joint movements.

## Abstract

The purpose of the study was to describe thumb kinematics and function during basic motion tasks and activities of daily living following different surgical techniques for trapeziometacarpal (TMC) joint osteoarthritis using a three-dimensional motion capture system.

Included were 24 patients (29 thumbs) following Wilson osteotomy, Touch prosthesis arthroplasty and trapeziectomy with ligament reconstruction and tendon interposition (LRTI) at a minimum of 12 months postoperatively.

During basic motion tasks, it was observed that patients after LRTI showed alterations in most of the assessed movements, while osteotomy and Touch patients showed a preserved range of motion. Altered mobility of the TMC joint was more evident in the combined movements of opposition or circumduction compared with standard anatomical planes. In activities of daily living, we found a similar range of motion of the trapeziometacarpal joint in all groups, but different movements in the adjacent joints, including marked hyperextension of the metacarpophalangeal joint in the LRTI group.

Our study found different preservation of the maximal ROM following different TMC joint procedures. Information about the higher preserved range of motion following osteotomy and arthroplasty may be additional factors for consideration when choosing a procedure. Three-dimensional assessment of thumb kinematics after various trapeziometacarpal joint surgeries can enhance our understanding of expected outcomes and can also aid in postoperative assessment and patient education.

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