In vitro Biomechanical Analysis of Proximal Phalangeal Osteotomy Fixation

Abstract

Background Corrective osteotomies of the proximal phalanx are typically stabilized with plate and screws. Although intramedullary headless screws form an alternative fixation method in the treatment of acute phalangeal fractures, reports about fixation of opening wedge corrective osteotomies with these implants are lacking.

Objective The goal of the present study was to biomechanically compare the failure force of both fixation methods for this specific indication.

Methods Twenty-four cadaver phalanges were equally distributed between apex volar and apex lateral opening wedge osteotomy groups. In each group, half of the osteotomies were fixed with a 1.3-mm dorsal locking plate, the other half with a 2.4-mm intramedullary headless screw. A three-point bending test was performed.

Results The mean maximal failure force after apex lateral osteotomy was 178.4 N for the plate-screw construct and 144.0 N after intramedullary headless screw fixation. After apex volar osteotomy, mean maximal force was 237.6 N in the plate-screw group and 160.9 N in the intramedullary headless screw group. Mean stiffness after apex lateral osteotomy was 63.3 N/mm in the plate-screw group, and 55.9 N/mm in the intramedullary headless screw group. Mean stiffness after apex volar osteotomy was 197.5 N/mm and 60.0 N/mm for the plate-screw and intramedullary headless screw group, respectively.

Conclusion For apex volar osteotomies, dorsally applied angular stable plate and screws provide significantly stronger fixation than intramedullary headless screws. For apex lateral osteotomies, fixation force is comparable.

Clinical relevance These data are useful when considering fixation of opening wedge osteotomies with intramedullary screws.

Keywords

corrective osteotomy - proximal - phalanx - intramedullary screw - plate

Ethical Approval

This study received Institutional Ethical Committee approval (Hasselt University, CME2018/073).

Publication History

Received: 22 June 2020

Accepted: 19 October 2020

Article published online:
03 January 2021

• References

• 1 Shewring DJ, Trickett RW, Smith A. Fractures at the junction of diaphysis and metaphysis of the proximal phalanges in adults. J Hand Surg Eur Vol 2018; 43 (05) 506-512
• 2 Harness NG, Chen A, Jupiter JB. Extra-articular osteotomy for malunited unicondylar fractures of the proximal phalanx. J Hand Surg Am 2005; 30 (03) 566-572
• 3 Seo BF, Kim DJ, Lee JY, Kwon H, Jung SN. Minimally invasive correction of phalangeal malunion under local anaesthesia. Acta Orthop Belg 2013; 79 (05) 592-595
• 4 Potenza V, De Luna V, Maglione P, Garro L, Farsetti P, Caterini R. Post-traumatic malunion of the proximal phalanx of the finger. Medium-term results in 24 cases treated by “in situ” osteotomy. Open Orthop J 2012; 6: 468-472
• 5 del Piñal F, Moraleda E, Rúas JS, de Piero GH, Cerezal L. Minimally invasive fixation of fractures of the phalanges and metacarpals with intramedullary cannulated headless compression screws. J Hand Surg Am 2015; 40 (04) 692-700
• 6 Prevel CD, Katona T, Eppley BL, Moore K, McCarty M, Ge J. A biomechanical analysis of the stability of titanium bone fixation systems in proximal phalangeal fractures. Ann Plast Surg 1996; 37 (05) 473-481
• 7 Abe Y. A simple, easy, and reliable technique of phalangeal corrective osteotomy for overlapping fingers. Plast Reconstr Surg Glob Open 2015; 3 (07) e454
• 8 Nunley JA, Kloen P. Biomechanical and functional testing of plate fixation devices for proximal phalangeal fractures. J Hand Surg Am 1991; 16 (06) 991-998
• 9 Schuind F, Garcia-Elias M, Cooney III WP, An KN. Flexor tendon forces: in vivo measurements. J Hand Surg Am 1992; 17 (02) 291-298
• 10 Lu SC, Vereecke EE, Synek A, Pahr DH, Kivell TL. A novel experimental design for the measurement of metacarpal bone loading and deformation and fingertip force. PeerJ 2018; 6: e5480