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3D-printed splint for mallet finger injury
used in the treatment of this condition. Either cast splints in the treatment of mallet finger has been
molded products known as “off the shelf,” which reported by O’Brien . All three types of splints
[13]
are manufactured in three ready-made sizes or are required to be worn for 6 – 8 weeks. Treatment
personalized molded thermoplastic products that failure or complications include skin irritation,
a health professional makes for the patient at the poor splint fit, splint breakage, pain, or discomfort
clinic. The stack splint is generally made from wearing the splint or patient dissatisfaction with
polypropylene and is largely enclosed with limited splint appearance or cumbersome nature. When
holes in the top section for airflow. The stack splint worn for the entirety of this period, there was no
is applied to the patient’s finger and then attached extensor lag difference found between the three
to the skin on the proximal phalange with skin splint types, but custom-made thermoplastic
tape or strapping tape to help prevent movement. splints were significantly less likely to result in
However, the “off the shelf” splints embody a one treatment failure .
[13]
size fits all approach which cannot accommodate This suggests that customized splints, fitted to
all patients. the exact dimensions of a patient’s finger, have
The dorsal aluminum splint is a commonly the ability to provide successful treatment in more
prescribed method for treating mallet finger. This cases than the other two splint types. This finding
method utilizes a splint on the dorsal section of propelled the current study to use AM technology
the finger and then taped onto the finger at the to rapidly produce the personalized fitted shape
distal phalange and the intermediate phalange. splint customized to the patient. This technology
This method provides greater airflow than the could provide a standardized and efficient
stack splint as the ventral section of the finger approach to manufacturing mallet splints that may
and the fingertip is left open to the air. This reduce cost, improve adherence, and have less
theoretically provides an advantage over stack impact on patient’s hand function while wearing
splint in that decreased pressure is exerted to the the splint.
distal interphalangeal joint, allowing better blood 1.3 AM
supply .
[7]
Personalized thermoplastic splints are applied AM is a promising and developing manufacturing
by trained health professionals, which involves method. Historically, AM technology was utilized
taking the measurements of a patient’s finger and for prototype creation; increasingly, however, it is
then cutting a piece of thermoplastic to a specific being seen and has become a production technique
splint design. The thermoplastic is heated, and the in its own right [14,15] . The AM groups a large number
finger is wrapped in the thermoplastic with the tabs of technologies and techniques that can utilize
joining the piece over the top of the finger. Using different materials with vastly differing properties
scissors, a health professional can trim the ends to create parts for a range of applications .
[16]
further to better fit the patient. The thermoplastic The three-dimensional (3D) printing has become
conforms to the skin and sets when it cools, a large part of the new frontier of medical technology
maintaining the finger in the position that it has and treatment. Medical treatments that use 3D
been molded to. There are several complexities printing techniques include: Facial reconstruction,
with this manufacturing process, including that the orthodontics, exoskeletons, prosthesis, tumor
manufacturing process is manual and highly skill detection, chirurgical optimization and biocompatible
dependent. The splint received from a graduate organ, and tissue printing [17,18] . In the medical field,
health professional may be completely different using traditional manufacturing methods take a lot
in quality to the veteran therapist who has been of production time and are not easily customizable
creating these splints by hand for years. The to patients; hence, its use is becoming more limited.
splint, if poorly fitted, can result in shear stress, FDM, also known as fused filament fabrication, is
directional misalignment, and pressure over bony one of the most common AM technologies using
prominences . A comparison study of these three numerous varieties of thermoplastic materials [19,20] .
[9]
18 International Journal of Bioprinting (2020)–Volume 6, Issue 2