Aims: There is ambiguity surrounding the degree of scaphoid union required to safely allow mobilization following scaphoid waist fracture. Premature mobilization could lead to refracture, but late mobilization may cause stiffness and delay return to normal function. This study aims to explore the risk of refracture at different stages of scaphoid waist fracture union in three common fracture patterns, using a novel finite element method.

Methods: The most common anatomical variant of the scaphoid was modelled from a CT scan of a healthy hand and wrist using 3D Slicer freeware. This model was uploaded into COMSOL Multiphysics software to enable the application of physiological enhancements. Three common waist fracture patterns were produced following the Russe classification. Each fracture had differing stages of healing, ranging from 10% to 90% partial union, with increments of 10% union assessed. A physiological force of 100 N acting on the distal pole was applied, with the risk of refracture assessed using the Von Mises stress.

Results: Overall, 90% to 30% fracture unions demonstrated a small, gradual increase in the Von Mises stress of all fracture patterns (16.0 MPa to 240.5 MPa). All fracture patterns showed a greater increase in Von Mises stress from 30% to 10% partial union (680.8 MPa to 6,288.6 MPa).

Conclusion: Previous studies have suggested 25%, 50%, and 75% partial union as sufficient for resuming hand and wrist mobilization. This study shows that 30% union is sufficient to return to normal hand and wrist function in all three fracture patterns. Both 50% and 75% union are unnecessary and increase the risk of post-fracture stiffness. This study has also demonstrated the feasibility of finite element analysis (FEA) in scaphoid waist fracture research. FEA is a sustainable method which does not require the use of finite scaphoid cadavers, hence increasing accessibility into future scaphoid waist fracture-related research.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10440191PMC
http://dx.doi.org/10.1302/2633-1462.48.BJO-2023-0058.R1DOI Listing

Publication Analysis

Top Keywords

scaphoid waist
20
fracture patterns
20
partial union
16
waist fracture
16
hand wrist
12
von mises
12
fracture
10
union
9
scaphoid
8
return normal
8

Similar Publications

Background: Achieving bony union in scaphoid nonunion fractures is challenging. Various bone grafts have been studied using headless compression screws (HCS) fixation. However, the impact of bone graft choice on bone healing with volar locking plates (VLP) use is less clear.

View Article and Find Full Text PDF

Purpose: The Evidence-Based Practice Committee of the American Society for Surgery of the Hand set out to assess the membership's practice patterns (PPs) and familiarity with evidence-based principles for scaphoid fracture and nonunion management.

Methods: Using a consensus-generated 25-item online survey, all the American Society for Surgery of the Hand members were invited to participate via email in September 2023. Two question types were used including evidence-based practice (EBP) and PPs.

View Article and Find Full Text PDF

Introduction: Scaphoid fractures are one of the most common carpal bone fractures, with most fractures involving the waist. When surgery is indicated, internal fixation with screws is the standard method for the fixation of these fractures. Accurate length and trajectory of the screw are two crucial parameters essential for optimal internal fixation.

View Article and Find Full Text PDF

Background: Scaphoid nonunion often requires surgical management involving the combination of a bone graft and internal fixation to restore the carpal alignment and length. While traditionally, the scaphoid waist nonunions have been treated with open bone grafts, with the advent of arthroscopy, bone graft reconstruction can now be carried out as an arthroscopic assisted minimally invasive procedure. We aimed to compare outcomes between open and arthroscopic bone grafting in the treatment of scaphoid nonunion.

View Article and Find Full Text PDF

Purpose Of Review: Scaphoid fractures are commonly encountered injuries in the athletic population. Conservative management is pursued for incomplete fractures and those involving the distal pole. Operative management is indicated for displaced fractures, unstable fractures, and those involving the proximal pole.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!