Related Experiment Video
Updated: May 17, 2026
08:18
Engineered Vascularized Muscle Flap
Published on: January 11, 2016
The keystone flap: not an advance, just a stretch
Charles D Douglas1, Nelson C K Low, Michael J Seitz
1Discipline of Surgical Science, The University of Newcastle, Newcastle, NSW, Australia. charles.douglas@newcastle.edu.au
Annals of Surgical Oncology
|October 12, 2012
Summary
The keystone flap
Area of Science:
- Surgical Reconstruction
- Oncology
- Dermatology
Background:
- The keystone flap is a novel island flap technique for oncological surgical reconstruction.
- This flap design involves V-Y advancements intended to facilitate wound closure.
- The underlying principle suggests longitudinal axis release aids transverse skin stretching.
Purpose of the Study:
- To investigate the biomechanical principles of the keystone flap.
- To test the hypothesis that longitudinal axis relaxation enhances transverse skin stretch for wound closure.
Main Methods:
- Excised human skin specimens were used to measure tension and extension.
- Skin tension was analyzed along perpendicular axes under varying conditions.
- The effect of longitudinal axis release on transverse tension and extension was quantified.
Main Results:
- Significant interdependence was observed between longitudinal and transverse skin tensions.
- The reduction in transverse tension upon longitudinal release varied based on initial tension and specimen orientation.
- A mean increase of 0.6 mm in transverse stretch was noted after longitudinal release from in vivo length.
Conclusions:
- The observed increase in transverse stretch from longitudinal release is minimal.
- This finding questions the biomechanical rationale for the prototypical (type 1) keystone flap in wound closure.
- Further research may be needed to validate the clinical utility of this flap design.
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