Please use this identifier to cite or link to this item:
Title: An intramedullary Echidna pin for fixation of comminuted clavicle fractures: a biomechanical study.
Authors: Patel, Minoo
Richardson, Martin
Other Authors: Ackland, David
Griggs, Ian
Hislop, Patrick
Wu, Wen
Keywords: Biomechanics
Repair Construct
Upper Limb
Clavicle Fractures
Intramedullary Echidna Pin Device
Herbert Cannulated Bone Screw System
Bi-Cortical Locking Screws
Intramedullary Fixation
Clinical Outcomes
Fracture Reduction
Removal, Post-Operative
Migration, Resistance
Clavicle Specimens
Construct Bending
Torsional Stiffness
Bending Strength
Department of Surgery, Epworth Healthcare, Melbourne, Victoria, Australia
Centre for Limb Reconstruction, The Epworth Centre, Richmond, Victoria, Australia.
Musculoskeletal Clinical Institute, Epworth HealthCare, Victoria, Australia
Issue Date: Aug-2017
Publisher: BioMed Central
Citation: J Orthop Surg Res. 2017 Aug 11;12(1):122
Abstract: BACKGROUND: Intramedullary fixation of comminuted mid-shaft clavicle fractures has traditionally been employed with satisfactory clinical outcomes; however, pins with smooth surfaces may protrude from the bone and are prone to migration, while some threaded pins are difficult to remove post-operatively. The aim of this proof-of-concept study was to develop and evaluate the biomechanical strength of a novel intramedullary Echidna pin device designed to maintain fracture reduction, resist migration and facilitate ease of post-operative removal. METHODS: Thirty human clavicle specimens were harvested and fractured in a comminuted mid-shaft butterfly configuration. Each specimen was randomly allocated to three surgical repair groups including intramedullary fixation using the Echidna pin and Herbert Cannulated Bone Screw System, as well as plate fixation using bi-cortical locking screws. Using a biomechanical testing apparatus, construct bending and torsional stiffness were measured, as well as ultimate bending strength. RESULTS: There was no significant difference in torsional stiffness and ultimate bending moment between the Echidna pin and Herbert screw repair constructs (p > 0.05); however, the Echidna pin construct demonstrated a significantly greater bending stiffness compared to that of the Herbert screw construct (mean difference 0.55 Nm/deg., p = 0.001). The plate construct demonstrated significantly greater torsional stiffness, bending stiffness and ultimate bending moment compared to those of the Herbert screw and Echidna pin (p < 0.05). CONCLUSIONS: An intramedullary Echidna pin device was designed to stabilize comminuted fractures of the clavicle, maintain fracture compression and provide ease of removal post-operatively. Since the results suggest equivalent or superior torsional and bending stability in the Echidna pin compared to that of the Herbert screw, the Echidna pin concept may represent an alternative fixation device to conventional intramedullary screws, nails and pins; however, superior plating using bi-cortical locking screws provides substantially higher construct structural rigidity than intramedullary devices, and may therefore be useful in cases of osteoporotic bone, or where high fracture stability is required.
DOI: 10.1186/s13018-017-0623-y
PubMed URL:
ISSN: 1749-799X
Journal Title: Journal of Orthopaedic Surgery and Research
Type: Journal Article
Affiliated Organisations: Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria, Australia
Department of Surgery, Southern Clinical School, Monash University, Victoria, Australia
Type of Clinical Study or Trial: Comparative Study
Appears in Collections:General Surgery and Gastroenterology

Files in This Item:
File Description SizeFormat  
Ackland et al 2017.pdf1.47 MBAdobe PDFView/Open

Items in Epworth are protected by copyright, with all rights reserved, unless otherwise indicated.