Application of 3D-Printed Orthopedic Cast for the Treatment of Forearm Fractures: Finite Element Analysis and Comparative Clinical Assessment

Abstract

Objective. This pilot study is aimed at investigating the mechanical characteristics of a cast-wrapped fractured forearm and performing a clinical comparative study of our own developed 3D-printed orthopedic cast. Methods. An integrated finite element (FE) model including a forearm and a 3D-printed cast wrapping the forearm was created. The distal radial ulna in this model was cut through to mimic the bone fracture. A 400 N force and 1 Nm rotation moment, which were much larger than the loading conditions encountered in daily life for a human being, were applied on the palm. We conducted a comparative clinical study by using statistical assessment. 60 patients with forearm fractures were selected and treated with manual reduction and external fixation cast. All patients were divided into three groups with equal members (20): (a) 3D-printed external cast group, (b) traditional plaster external fixation group, and (c) splint external fixation group. The clinical efficacy, wrist function, and patient satisfaction were scored and compared. Results. In the condition of 400 N loading, the fracture displacements in anterior-posterior (AP), posterior-anterior (PA), medial to lateral (ML), and lateral to medial (LM) compression directions were 1.2648, 1.3253, 0.8503, and 0.8957 (mm), respectively, and the corresponding fracture stresses were 4.5986, 3.9129, and 5.0334, 7.9197 (MPa), respectively. In the inward (IR) and outward (OR) rotations, the fracture displacements were both 0.02628 (mm), and the corresponding fracture surface stresses were 0.1733 and 0.1723 (MPa), respectively. In the clinical efficacy, wrist function, and patient comfort evaluation, the total scores of group A were both higher than those in groups B and C (P<0.05). Conclusion. A 3D-printed orthopedic cast was capable of exerting appropriate mechanical correction loads on specific areas to maintain optimal alignment of a fractured forearm and thus could achieve the favorable clinical efficacy and patient comfort.

Effectiveness of 3D-printed orthoses for traumatic and chronic hand conditions: A scoping review

“…Four RCTs [ 25 , 26 , 33 , 40 ] and four UCTs [ 24 , 32 , 34 , 38 ] were critically appraised. The quality scores, presented in Table 3 , ranged from 11 to 21.…”

In Silico of Different Gait Cycle in Customised Leg Orthosis: A Finite Element Approach

“…Chen Y et al where the displacement of cast, bone and bone fracture were compared (Chen et al, 2020). Based on their results, it shows that different loading condition produces distinctly different output, with bone fracture displacements were ten times smaller than cast displacement.…”

A Review on: 3D Printed Orthopaedic Cast for Improved Forearm Fracture Rehabilitation

“…[9]. Studies have expected the cost of the cast to be around 15,000 -35,000 INR but it is expected to decrease in coming future [10]. Few of the 3D printed cast are being used in local centres in the USA, Latvia, Brazil and Spain.…”

“…The rapid growing technology will reduce the manufacturing cost in coming future. This will make the cast clinically feasible and its application widespread [10,14].…”