Biomechanical analysis of percutaneous all lateral pinning (Dorgan's technique) technique for supracondylar humerus fractures in children

• Published in: Journal of biomechanics 2011-01, Vol.44, p.10-10
• Main Authors: Memisoglu, Kaya, Musaoglu, Resul, Cengiz, Abdulkadir, Kesemenli, Cumhur C
• Format: Article
• Language: English
• Subjects: Biomechanical stability; Biomechanics; Bones; Children; Dorgan's; Fixation; Fracture mechanics; Humerus; Nerves; Physical Medicine and Rehabilitation; Pinning; Supracondylar humerus fracture
• ISSN: 0021-9290; 1873-2380
• DOI: 10.1016/j.jbiomech.2011.02.044

We tried to compare biomechanical properties of all lateral pinning (Dorgan's technique) with other pinning configurations used for humerus supracondylar fractures in children. In all lateral pinning technique iatrogenic nerve injury risk is minimized with secure fixation compared with other pin fixation configurations. Biomechanical testing was performed on 50 synthetic humeral bones (Keklikoglu). Transverse supracondylar humeral fractures were made with a hand-held saw above the olecranon fossa. Five different pin configurations were selected for fracture stabilization: 2 lateral pins and 1 medial pin (3 crossed), 2 laterally divergent pins, 2 crossed pins, 2 all laterally crossed pins (Dorgan's technique), 2 laterally parallel pins. All the pin configurations were fluoroscopically confirmed. The fractures were stabilized with 0.062″ Kirschner wires. Biomechanical tests were performed by torsional load producing machine with internal rotation of the distal fragment. All the models were subjected to torsional loads for 10 times between 5 and 50 N and rotation in degrees and corresponding torques were recorded for statistical analysis. The differences of the stiffness of the pin configurations [2 lateral pins and 1 medial pin (3 crossed), 2 laterally divergent pins, 2 crossed pins, 2 all lateral crossed pins (Dorgan's technique), 2 laterally parallel pins] were found, respectively, 0.06, 0.043, 0.039, 0.012 and 0.013 N m/degree. All lateral crossed pins (Dorgan's technique) showed biomechanically equal properties to the medio-lateral, lower to the 2 lateral and 1 medial pin, and superior to the other pin configurations. All lateral crossed pins do not jeopardize the ulnar nerve during insertion of the pins percutaneously and fix the fracture with low learning curve.