Study design: Two consecutive prospective case series. Study population: Part 1 will enroll 10 healthy volunteers (50 years or older). Part 2 will enroll 10 elderly patients (50 years or older) with a dorsally displaced distal radius fracture (AO type 23-A-C) that is acceptably reduced. In both parts, participants should have no restrictions in activities of daily living pre-fracture and no evident anatomical difference between both wrists.

Intervention:

Part 1: Participants will wear the brace continuously for one week. Part 2: Participants will wear the brace as treatment of the fracture for five weeks (instead of a plaster cast).

Main study parameters/endpoints: In parts 1 and 2, the primary outcome measure will be a Visual Analog Scale (VAS) score for wearing comfort. Secondary outcome measures are the occurrence of fracture redislocation (part 2 only), pain (VAS), inconvenience during NL61002.078.17 / DRFB-Tolerability Distal Radius Fracture Brace Tolerability Version number: 1.1, d.d. April 24, 2017 8 of 34 activities of daily living (Katz Index), and adverse reactions like pain, skin pressure, skin irritation/redness, sensibility issues, or device-related problems.

Rationale: Each year, approximately 34,500 adults in The Netherlands sustain a fracture of the distal radius (wrist fracture). Incidence peaks in the elderly. The currently preferred treatment is closed reduction and nonoperative treatment by immobilization in a plaster cast for 4-6 weeks. Surgery is only performed if closed reduction fails or redislocation occurs. Plaster immobilization is inconvenient and interferes with daily activities. More importantly, standard nonoperative treatment often fails; in 40-60% of the fractures, redislocation requires surgery. Surgical treatment is about 9 times more expensive than nonoperative treatment and not without risks. This project aims to develop an innovative nonoperative treatment option. The central idea is to produce a 3D-printed brace for the fractured wrist using a mirrored CT-scan of the contralateral, unfractured wrist as a model. This innovative approach has the advantage that it does not depend on surgery and provides a better and potentially more durable positioning than the currently applied plaster cast. We expect that redislocation will occur less frequently, so surgery may be avoided. In contrast to a traditional plaster cast, the newly developed brace is water resistant/repellant, lighter, and enables movement of the hand. It enables daily activities and improves independency in the elderly with a wrist fracture. The treatment has been successfully evaluated in an ex vivo model. The clinical implementation will follow a step-wise approach.

Objective: Part 1 aims to determine the tolerability of the 3D-printed brace when worn by healthy volunteers (50 years of order), performing their normal daily activities. In part 2, the objective is to determine tolerability of the 3D-printed brace in patients (50 years or older) with an extra-articular distal radius fracture with dorsal displacement, performing their normal daily activities.

Inclusion Criteria:

Part 1:

1. Age 50 years or older
2. Healthy volunteer without distal radius fracture
3. No restrictions in activities of daily living prior to enrolment*
4. Signed informed consent by participant * Participant should exercises complete self-control over urination and defecation, but use of incontinence material is allowed.

Part 2:

1. Patients (50 years or older) with an acute**, unilateral distal radius fracture with dorsal displacement (AO type 23-A, B, or C) that is acceptably reduced (by simple closed reduction with vertical longitudinal traction)

2. No restrictions in activities of daily living pre-fracture*

3. Signed informed consent by patient

   • Participant should exercises complete self-control over urination and defecation, but use of incontinence material is allowed. ** Patients should report to the Emergency Department within 48h post-trauma.

Exclusion Criteria:

Part 1:

1. Preexisting anatomical deviation of the ipsi- or contralateral wrist
2. Conditions that affect function of the wrist or hand
3. Insufficient comprehension of the Dutch or language to understand the study documents
4. Participant unwilling or unable to comply with the study protocol and follow-up visit schedule
5. Known allergy for brace material (PLA or alternative)

Part 2:

1. Preexisting anatomical deviation of the ipsi- or contralateral wrist
2. Additional traumatic injuries that affect treatment, rehabilitation, or function of the affected hand
3. Pathological, recurrent, or open fracture
4. Impaired wrist function pre-trauma at either wrist (e.g., arthrosis, rheumatoid disorder, or neurological disorder)
5. Bone disorder that may impair bone healing, excluding osteoporosis
6. Patient unwilling or unable to comply with the treatment protocol and follow-up visit schedule
7. Insufficient comprehension of the Dutch language to understand the study documents
8. Known allergy for brace material (PLA or alternative).

For part 1, a randomization list will be generated using an online program. For the 10 participants, five braces will be developed for the dominant side and five for the nondominant side. The physician and participant will be concealed for allocated side until the scan will be made.