Dynamic compression plate fixation: A biomechanical comparison of unicortical vs bicortical distal screw fixation

Stephen R. Davenport, Ronald W. Lindsey, Robert Leggon, Theodore Miclau, Manohar Panjabi

Research output: Contribution to journalArticle

25 Scopus citations


The use of unicortical screws instead of bicortical screws in the extreme outer holes of dynamic compression plates (DCPs) has been recommended to minimize the stress riser effect at the end of the plates. The authors examined in vitro two groups of paired canine femurs after compression plates had been applied to the anterolateral diaphyseal surface bilaterally. Group I: Intact paired femurs with bicortical peripheral screws in one DCP and unicortical peripheral screws in the other; Group II: Osteotomized paired femurs again comparing unicortical and bicortical peripheral DCP screws. All specimens were torsion tested to failure and the torque, stiffness, energy, rotation, and failure fracture length were calculated. Unicortical screws did not enhance the torsional strength in either group, and significantly compromised stiffness, energy, and rotation in the osteotomized group. The only apparent benefit of unicortical peripheral screws in a DCP was a shorter, less comminuted fracture upon failure.

Original languageEnglish (US)
Pages (from-to)146-150
Number of pages5
JournalJournal of orthopaedic trauma
Issue number2
StatePublished - Jan 1 1988
Externally publishedYes



  • Bicortical/unicortical screw fixation
  • Biomechanics
  • Complications
  • Dynamic compression plates

ASJC Scopus subject areas

  • Surgery
  • Orthopedics and Sports Medicine

Cite this