Biomechanical evaluation of cross-pin versus interference screw tibial fixation using a soft-tissue graft during transtibial posterior cruciate ligament reconstruction.
OBJECTIVE
This article reports the biomechanical demonstration of a technique for transtibial posterior cruciate ligament (PCL) reconstruction using a soft-tissue graft with cross-pin fixation in the tibia and compares this with the biomechanical properties achieved with other methods.


METHODS
We used 5 paired cadaveric knees and another 10 tibias. Soft-tissue grafts were randomized. The femoral side of the anterior cruciate ligament was fixed with a Bio-TransFix device (Arthrex, Naples, FL) (group I), and the tibial side of the PCL was fixed with a Bio-TransFix device (group II). In another 10 tibias, tibial fixations were performed by use of a bio-interference screw (group III). Biomechanical testing was carried out on a testing machine, and maximal failure load, stiffness, and displacement were analyzed. The lengths of the slots of the TransFix device (Arthrex) from the near cortex were measured to compare the proper length of the device.


RESULTS
Maximal mean failure loads in groups I, II, and III were 549.3 +/- 55.4 N, 570.8 +/- 96.9 N, and 371.3 +/- 106.2 N, respectively, showing a significant difference (P = .0003). Stiffnesses were 47.52 +/- 16.84 N/mm, 59.14 +/- 17.09 N/mm, and 27.60 +/- 16.73 N/mm, respectively, showing a significant difference (P = .01). Mean displacements were 19.99 +/- 5.79 mm, 19.09 +/- 8.51 mm, and 17.58 +/- 7.10 mm, respectively, showing no significant difference (P = .7535). The mean lengths of the slots of the TransFix device of the femurs and tibias were similar at 20.3 +/- 1.25 mm and 20.2 +/- 1.32 mm, respectively, showing no significant difference (P = .8637).


CONCLUSIONS
The transtibial technique by use of cross-pin tibial fixation with a Bio-TransFix device in PCL reconstruction provides stable fixation that is comparable to that achieved by use of conventional bio-interference screw fixation and femoral fixation in an anterior cruciate ligament reconstruction, an already well-established technique.


CONCLUSIONS
Biomechanically, tibial cross-pin fixation compares favorably with interference screw fixation and is useful when a graft is short. However, safety issues have not yet been resolved.
Lee
Yong Seuk
YS
Korea University Ansan Hospital, Anam-dong Seongbuk-Gu, Seoul, Korea. smcos1@hanmail.net
Wang
Joon Ho
JH
Bae
Ji Hoon
JH
Lim
Hong Chul
HC
Park
Jung Ho
JH
Ahn
Jin Hwan
JH
Bae
Tae Soo
TS
Lim
Bee-Oh
BO
D001696:Biomechanical Phenomena; D001843:Bone Cements; D002102:Cadaver; D016267:External Fixators; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D016119:Posterior Cruciate Ligament / Q000601:surgery*; D019736:Prostheses and Implants; D013977:Tibia / Q000601:surgery*
D001843:Bone Cements