A Novel Passive Implantable Differential Mechanism to Restore Individuated Finger Flexion during Grasping following Tendon Transfer Surgery: A Pilot Study
Abstract
Tendon transfer surgery is often used to restore hand grasp function following high median-ulnar nerve palsy. This surgery typically reroutes and sutures the tendon of the extensor carpi radialis longus (ECRL) muscle to all four flexor digitorum profundus (FDP) tendons of the hand, coupling them together. This makes it difficult to grasp irregularly shaped objects. We propose inserting a novel implantable passive device between the FDP tendons to surgically construct a differential mechanism, enabling the fingers to individually adapt to the irregular contours during grasping. These passive implants with no moving parts are fabricated from biocompatible materials. We tested the implants’ ability to create differential flexion between the index and middle fingers when actuated by a single muscle in two human cadaver hands using a computerized closed-loop control paradigm. In these cadaveric models, the implants enabled significantly more differential flexion between the index and middle fingers for a wide range of donor tendon tensions. The implants also redistributed fingertip forces between fingers. When grasping uneven objects, the difference in contact forces between fingers reduced by nearly 23% compared to the current suture-based surgery. These results suggest that self-adaptive grasp is possible in tendon transfers that drive multiple distal flexor tendons.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 08, 2023
- Source ID
- 10.3390/app13095804
Entities
People
- Francisco J Valero-Cuevas
- Justin C. Casebier
- Kian Jalaleddini
- Nina Lightdale-Miric
- Ravi Balasubramanian
- Suraj Chakravarthi Raja
- Vincent R. Hentz
- Won Suk You
Organizations
- Children's Hospital Los Angeles
- Congressionally Directed Medical Research Programs
- National Institute of Arthritis and Musculoskeletal and Skin Diseases
- National Science Foundation
- Oregon State University
- Stanford University
- University of Southern California