A Biomechanical Comparison of a Tendon Repair Device and 4 Stranded, Cruciate Repair Sutures for Flexor Tendon Ruptured
Surachet Tantadprasert MD*, Polasak Jeeravipoolvarn MD*, Weerachai Kosuwon MD*, Kowit Chaiyasivamongkon MD**
Affiliation : * Department of Orthopedic, Faculty of Medicine, Srinakarind hospital, Khon Kaen University, Khon Kaen, Thailand ** Department of Anatomy, Faculty of Medicine, Srinakarind hospital, Khon Kaen University, Khon Kaen, Thailand
Objective : To compare the biomechanical properties of the single strand monofilament Nylon 2-0 Khon Kaen
tendon repair device for flexor tendon repair and standard 4-stranded cruciate repair sutures.
Material and Method: 80 flexor digitorum longus tendons from fresh cadavers, were cut and sutured by Khon
Kaen tendon repair device (core nylon) or 4-stranded, cruciate repair (3-0 monofilament nylon) and both
groups were divided into two groups; the first group combined with 5-0 monofilament nylon circumferential
epitendinous suture and the second group without epitendinous suture. The sutured tendons were tested by
using biomechanical testing machine (LLOYD instruments, LR30K), in rate 5 mm/s. Force, stiffness and energy
absorbed at peak force (calculated from the force-displacement curves) and mode of failure were compared.
Results : The Khon Kaen tendon repair device (core nylon) without epitendinous sutured group has 2 mm gap
force, peak force and stiffness significantly lower than standard 4-stranded, cruciate repair, but with no
statistical difference in the epitendinous sutured group; 90% of Khon Kaen tendon repair device failed by
suture breakage and 10% failed by ankle pullout.
Conclusion : Although the strength of Khon Kaen tendon repair device (core nylon) alone is lower than the
strength of 4-stranded, cruciate repair, and 90% mode of failure was core suture breakage, the authors
recommended to change core suture from nylon to a stiffer material and re-inforced with epitendinous suture.
Keywords : Flexor tendon repair device, Tendon biomechanics, Suture techniques
