3D-printing a Cock-up Splint for Corrective Physical Therapy
3D-Printing in Medicine for Ethiopia
Here is a 5-year-old boy born with a congenital abnormality that caused his forearm bone (ulnar bone) to deform. To correct this, he is in physiotherapy and needs a nighttime cock-up splint. But unfortunately, the family couldn’t find a splint that would fit his tiny hand because the imports available are only for adult size and are a bit pricey. His physiotherapist who met us at a health exhibition recommended our 3D printing pilot study for this case. After discussing the needs and requirements for a splint, our research team came up with a design that would be molded onto the patient directly after being 3D printed. The design we modified according to our research reviews is shown in the image below (ofc with a few customizations and measurements for our patient hands).
The next step was to pick what material to use for this purpose. The item must be strong enough to hold and as durable as possible while we can also mold it onto the patient directly. The material scientist in the team recommended having a trial with just the PLA plastic (Poly Lactic Acid) which is typically used as 3D print material instead of our in-home manufactured PET plastic material recycled from plastic water bottles typically sold in the Ethiopian market. After getting the approval to print with PLA. Our mechanical engineering and design architect team designed a form that can mold onto the hand and have aesthetically functional openings in between as shown in the image. This can help in material saving as well as in increasing the comfort level of a patient wearing it because it makes it breathy. It is also useful for the doctors & physiotherapists to identify possible complications such as compartment syndrome.
The 3D-print on the first trial which was approved by his physiotherapist and casting was attempted. We then did the molding directly on the patient using a heat gun which can reach up to 60 degrees Celsius (140 Fahrenheit). The PLA plastic material is a type of polymer that changes shape with heat stimuli therefore by applying heat from the heat gun, we were able to assist his physiotherapist on the application of the 3D-printed splint onto the patient. (The white gauze on the patient hand is to prevent the slightly warm feeling while a heated 3D splint is applied directly to the patient_but apparently our brave little boy was enjoying the heat).
After about 4 trials and errors, we were able to mold a cast that perfectly fits our patient’s hand. The final stage of this process is to secure the splint so it can hold the deformed ulnar bone in place for our boy. Therefore, the design team customized these straps so the patient himself or with the help of his parents can take them out during the day and put them back on at night to hold the deformity in its corrected anatomical place.
We educated the family on the possible complications we might expect and to report any discomfort experienced by the patient. His physiotherapist was satisfied with the results and his parents were also grateful for this option being available in Ethiopia.
We were also happy to make a tiny difference in a little boy’s life. But our assignments are ever-lasting, and a lot of questions still dwell in our collective minds. We wonder to improve the customizable products we build for our patients. Currently, collecting patient-comfort level data and more reports to analyze and improve our 3D printed products. This is our first step towards a bigger, better future in medical technology and innovative solutions.
This is just our humble beginnings at CHi.
Join our team if you find this interesting!
Moy Tadesse, 3D Printing and Engineering
Salsawit Tesfaye Yigrem, Medical Innovations
Peredy Khwesa, Material Sciences
Dr. Brook, Physiotherapist
Dag, Designing & Smart Crafts
Naz, Intern at CHi