Biomechanical evaluation of different suture techniques for arthroscopic transtibial pull-out repair of posterior medial meniscus root tears.
BACKGROUND
A tear of the posterior medial meniscus root (PMMR) is increasingly recognized as a serious knee joint injury. Several suture techniques for arthroscopic transtibial pull-out repair have been described; however, only limited data about the biomechanical properties of these techniques are currently available.


HYPOTHESIS
There are significant differences between the tested suture techniques, with more complex suture configurations providing superior biomechanical properties.


STUDY DESIGN
Controlled laboratory study.


METHODS
A total of 40 porcine medial menisci were randomly assigned to 1 of 4 groups (10 specimens each) according to suture technique: two simple stitches (TSS), horizontal mattress suture (HMS), modified Mason-Allen suture (MMA), and two modified loop stitches (TLS). Meniscus-suture constructs were subjected to cyclic loading followed by load-to-failure testing in a servohydraulic material testing machine.


RESULTS
During cyclic loading, the HMS and TLS groups showed a significantly higher displacement after 100, 500, and 1000 cycles compared with the TSS and MMA groups. After 1000 cycles, the highest displacement was found for the TLS group, with significant differences compared with all other groups. During load-to-failure testing, the highest maximum load and yield load were observed for the MMA group, with statistically significant differences compared with the TSS and TLS groups. With regard to stiffness, the TSS and MMA groups showed significantly higher values compared with the HMS and TLS groups.


CONCLUSION
The MMA technique provided the best biomechanical properties with regard to cyclic loading and load-to-failure testing. The TSS technique seems to be a valuable alternative. Both the HMS and TLS techniques have the disadvantage of lower stiffness and higher displacement during cyclic loading.


CLINICAL RELEVANCE
Using a MMA technique may improve healing rates and avoid progressive extrusion of the medial meniscus after transtibial pull-out repair of PMMR tears. The TSS technique may be used as an alternative that is easier to perform, but a more careful rehabilitation program is possibly necessary to avoid early failure.
['Feucht|Matthias J|MJ|', 'Grande|Eduardo|E|', 'Brunhuber|Johannes|J|', 'Burgkart|Rainer|R|', 'Imhoff|Andreas B|AB|', 'Braun|Sepp|S|']
D000818:Animals D001696:Biomechanical Phenomena D050724:Fractures, Cartilage D007718:Knee Injuries D008422:Materials Testing D008592:Menisci, Tibial D012421:Rupture D013536:Suture Techniques D013537:Sutures D013552:Swine D013718:Tensile Strength D000070600:Tibial Meniscus Injuries D014945:Wound Healing
biomechanics pull-out repair meniscus meniscus root root tear knee Mason-Allen biomechanical testing