The Point Digit: A ratcheting prosthetic finger using advanced rapid manufacturing technology

The goal of the proposed project is to develop and commercialize a purely mechanical, ratcheting prosthetic
finger – the Point Digit – which 1) has an industry leading strength to weight ratio, 2) can be operated unilaterally
(one-handed), 3) offers anatomical rotation and flexion around the patient’s metacarpophalangeal (MCP) joint,
and 4) can be custom-made for each patient using advanced metal 3D printing technology.
The care of upper limb amputees requires a highly individualized approach to medicine. Each patient brings
unique needs to the clinic including various levels of amputation, lifestyles, personal experience, and other
medical indicators. Prosthetists and occupational therapists work with each patient to provide a personalized
medical solution using whatever components and technologies are available on the open market. Very often, the
bottleneck in this system is the development of clinically sound prosthetic components that can be readily
sourced by the prosthetists to provide an optimal prosthetic limb system.
The largest population of upper limb amputees are those with partial hand amputations. This population
outnumbers all other levels of upper limb amputees by a factor of 10. Therefore, we can make a significant
clinical impact if a product serves this population effectively. However, current commercial products for partial
hand amputees do not satisfy all of the needs of these patients; passive fingers are seen as being fragile and
difficult to use while powered fingers are expensive and require additional components like batteries and
electronics that can be cumbersome to the user.
In this Fast Track effort, we propose to 1) internally verify the Point Digit through a battery of mechanical tests,
2) validate the user needs of the Point Digit with partial hand amputees for regulatory requirements and 3) assess
the utility of the Point Digit through a clinical take-home study of partial hand amputees.
The mission of Point Designs LLC is to innovate devices and algorithms in the field of upper limb prosthetic
design. We develop products that provide prosthetists and patients with solutions to meet the unique needs of
each patient in this dynamic and challenging healthcare setting. The Point Digit will provide an effective and
durable solution for many upper limb amputees with finger loss and ensure their ability to enjoy their work, family,
and life to the fullest.Point Designs LLC proposes to develop and commercialize a purely mechanical, ratcheting prosthetic finger –
independent from electronics and batteries, thereby reducing cost, size, and complexity while increasing
reliability and durability – that can be custom-made for each patient using advanced metal 3D-printing
technology. The amputation of full or partial fingers can cause physical, psychosocial, and economic damage to
an individual. Replacement of a finger requires a mechanical design that can withstand the forces, torques, and
environmental conditions of everyday life.