Science News: Current and Emerging Prostheses for Partial Hand Amputation: A Narrative Review

Submitted by: Oksana Sayko, MD
Edited by: Pritikanta Paul, MD

Citation: Kim GM, Powell JE, Lacey SA, Butkus JA, Smith DG. Current and emerging prostheses for partial hand amputation: A narrative review. PM R. 2023;15(3):392-401. doi:10.1002/pmrj.12764

Summary: Partial hand amputation leads to significant impacts on a person's life, causing a wide range of functional losses. Various partial hand prosthetic devices exist, differing in function and appearance. However, there is no ideal replacement for the lost hand. Often, those with partial hand amputation need multiple prosthetic devices. This review examines and compares different prosthetic choices, including passive, body-powered, activity-specific, and externally powered options.

Passive prostheses do not provide active movement but are designed to look like natural hand and fingers. Although passive partial hand prostheses lack active movement, such as a grip or release, they still do provide support for pushing, pulling, or holding objects. Realistic silicone partial hand prostheses can offer impressive cosmetic results. They are offered by various companies and are typically suction fitting.

Among trans-radial amputees, there is an abundance of activity-specific prosthetic tools utilized for activities of daily living, sports, and occupation.

Body-powered prostheses harness power from the residual limb using a system of cables, spring, and harnesses. Loss of function from multiple digital amputations or partial hand amputation presents unique challenges for prosthetic design and implementation, and this is frequently addressed using body-powered prostheses. Some body-powered prostheses are driven by the residual hand itself, rather than a more proximal aspect of the limb.

Externally powered prostheses utilize motor and batteries to provide movement and power to the prosthesis. Although externally powered prosthetic hands have been commercially available for decades, externally powered digit systems have been challenged by their innate spatial limitations. The externally powered prosthesis typically allows substantially stronger grip strength with less physiological cost on the surrounding joints. This type of prostheses typically uses signals from the user’s muscle activation to predict their intention to control the hand. Among the commercially available ones, surface electromyography (EMG) or myoelectrode, is more frequently used due to its portability and non-invasiveness.

Comments: To choose the best prosthesis amongst many options for patients with partial hand amputation, it is vital to consider the patient’s current functional levels, impact of the aesthetic loss and disfigurement, and desired functional and aesthetic goals while being cognizant of the benefits and limitations. Individuals with partial hand amputation may need multiple devices to address their needs. Finally, it is important to work in a multidisciplinary setting with physiatrists, hand surgeons, occupational therapists, and prosthetists.