Casting Versus Flexible Intramedullary Nailing in Displaced Pediatric Forearm Shaft Fractures

Casting Versus Flexible Intramedullary Nailing in Displaced Forearm Shaft Fractures in 7 to 12 Years Old Children: A Study Protocol for a Randomized Controlled Trial

The forearm is the most common fracture location in children, with an increasing incidence. Displaced forearm shaft fractures have traditionally been treated with closed reduction and cast immobilization. Diaphyseal fractures in children have poor remodeling capacity, and malunion can thus cause permanent cosmetic and functional disability. Internal fixation especially with flexible intramedullary nails has gained increasing popularity, without evidence of a better outcome compared to closed reduction and cast immobilization.

This is a multicenter, randomized superiority trial comparing closed reduction and cast immobilization to flexible intramedullary nails in 7-12 year old children with > 10° of angulation and/or > 10mm of shortening in displaced both bone forearm shaft fractures (AO-pediatric classification: 22D/2.1-5.2). A total of 78 patients with minimum 2 years of expected growth left are randomized in 1:1 ratio to either treatment group. The study has a parallel non-randomized patient preference arm. Both treatments are performed under general anesthesia. In the cast group a long arm cast is applied for 6 weeks. The flexible intramedullary nail group is immobilized in a collar and cuff sling for 4 weeks. Data is collected at baseline and at each follow-up until 1 year. Primary outcome is 1) PROMIS Pediatric Item Bank v2.0 - Upper Extremity and 2) forearm pronation-supination range of motion at one-year follow-up. Secondary outcomes are Quick DASH, Pediatric pain questionnaire, Cosmetic VAS, wrist range of motion as well as any complications (malunion, delayed union, non-union or deep wound infection, peripheral nerve injury, need for re-intervention during 1-year follow-up) and costs of treatment. The investigators hypothesize that flexible intramedullary nailing results in a superior outcome.

Fracture reduction and fixation using flexible intramedullary nails. Nails size is 0.4 times the smallest diameter of the medullary canal of radius or ulna measured in radiographs.

Fractures are reduced under general anesthesia within 3 days from injury and a synthetic circular above elbow cast in neutral pro-supination is applied for six weeks.

Fracture reduction and fixation using flexible intramedullary nails. Nails size is 0.4 times the smallest diameter of the medullary canal of radius or ulna measured in radiographs.

Fractures are reduced under general anesthesia within 3 days from injury and a synthetic circular above elbow cast in neutral pro-supination is applied for six weeks.

We aim to confirm that 75 percent of FIN patients have a better PROMIS UE score than what the mean score of the cast patients will be assuming both groups have the same standard deviation. PROMIS (Patient-Reported Outcomes Measurement Information System) scores are normalized to a mean score of 50, standard deviation of 10, with a theoretical range of 0 to 100. A higher score corresponds to a greater amount of the domain being measured.

Difference (percent) in forearm pronation-supination range of motion (ROM) at one-year follow-up in comparison to uninjured side.

Minimum value is 0 and maximum 100. Higher value indicates worse function. Statistically significant difference in QuickDASH score is 6.8 (18) at 12 months FU.

Minimum value is 0 and maximum value is 100. Higher score indicates better health related quality of life.

Measurement Model for the Pediatric Quality of Life Inventory Pediatric Pain Questionaire (PEDS QL PPQ)

malunion, delayed union (defined as nonunion at 3 months or later), pseudoarthrosis (defined as 3 cortices out of 4 not united at 6 months or later)

Difference (percent) in elbow, wrist flexion extension and pronation-supination in comparison to uninjured side

Level of practiced sport or musical instrument before and at end of trial, as well as time from injury to return to hobby is registered.

Inclusion Criteria: 7 to12 year old children Open distal radial physis Both bone forearm shaft fractures (AO-pediatric classification: 22D/2.1-5.2) More than 10 degrees of angulation with or without less than 10mm of shortening Exclusion Criteria: Patients with bilateral fractures Gustilo-Anderson grade I-III open fracture Neurovascular deficit Compartment syndrome Pathologic fracture Patient not able to give a written informed consent

Study protocol is published in BMJ open. What can not be found there can be shared by contacting the main investigator.

Grahn P, Sinikumpu JJ, Nietosvaara Y, Syvanen J, Salonen A, Ahonen M, Helenius I. Casting versus flexible intramedullary nailing in displaced forearm shaft fractures in children aged 7-12 years: a study protocol for a randomised controlled trial. BMJ Open. 2021 Aug 20;11(8):e048248. doi: 10.1136/bmjopen-2020-048248.