Middle Finger Abduction Exercise Focusing on the Intrinsic Muscles as Components of the Hand Arch
1)Department of Rehabilitation Medicine, Nippon Medical School Chiba Hokusoh Hospital
2)Department of Orthopaedic Surgery, Inada Hospital
3)Department of Orthopaedic Surgery, Nippon Medical School Chiba Hokusoh Hospital
4)Department of Rehabilitation Medicine, Tokyo Metropolitan Rehabilitation Hospital
5)Department of Rehabilitation and Physical Medicine, Graduate School of Medicine, Nippon Medical School
Background: We have observed that patients with restricted thumb opposition sometimes develop dysfunction of the intrinsic muscles around the metacarpal joint of the middle finger. Therefore, we developed a middle finger abduction exercise program which focuses on improvement of intrinsic muscle function during post-operative rehabilitation after thumb carpometacarpal arthroplasty. We report on the efficacy of the program herein.
Methods: Three patients with Eaton stage III-IV thumb carpometacarpal arthritis were included in the study. The effects of the exercise program were recorded. Ultrasonography and surface electromyography were used to evaluate the effects of the exercise in two healthy volunteers.
Results: Five minutes of exercise resulted in a 1- to 2-point improvement in the Kapandji opposition score, and a 1- to 3-cm improvement in thumb opposition to the base of the small finger. Ultrasonography and electromyography revealed that adductor pollicis, abductor pollicis brevis, opponens pollicis, and abductor digiti minimi contractions became more synchronous.
Conclusion: Our middle finger abduction exercise program improves thumb opposition significantly. The program may be particularly useful for post-operative rehabilitation after thumb surgeries: thumb opposition can be improved without thumb motion, which can be painful in the early post-operative period.
日医大医会誌 2018; 14(3), 125-130
intrinsic muscles, hand arch, thumb carpometacarpal arthritis, middle finger abduction exercise, opposition improvement
Yusuke Hagiwara, Department of Orthopaedic Surgery, Inada Hospital, 46 Omori-cho, Nara-shi, Nara 630-8131, Japan