Effect of femoral tunnel length on the safety of anterior cruciate ligament graft fixation using cross-pin technique: a cadaveric study.
BACKGROUND
A more oblique placement of the anterior cruciate ligament (ACL) graft has been related to better control of rotatory knee stability. Femoral fixation with a transverse system might injure its posterolateral structures.


OBJECTIVE
A cross-pin system, originally developed for transtibial reconstruction of the ACL, can safely be used when creating a lower femoral tunnel through the anteromedial portal. However, a long femoral tunnel must be created to protect the posterolateral structures of the knee.


METHODS
Controlled laboratory study.


METHODS
An ACL was arthroscopically reconstructed with a hamstring graft in 22 fresh cadaveric knees. The femoral tunnel was anatomically drilled in all cases. Knee flexion angle was set at 110 degrees . Femoral fixation was performed with a cross-pin system. A 30-mm-long femoral tunnel was created in 11 knees (group A). In the remaining 11 knees, the femoral tunnel was drilled as long as each lateral condyle permitted (group B). For both groups, the relationships were compared between the cross-pin and the lateral collateral ligament (LCL), popliteus tendon, articular cartilage, and peroneal nerve.


RESULTS
In 5 cases of group A, the cross-pin was placed either through the LCL or between the LCL and popliteus tendon, whereas in group B it was always posterior to the LCL (P = .035). The cross-pin was closer to the articular cartilage in group A than in group B (7.14 mm versus 16.9 mm; P < .001). The minimal distance to the peroneal nerve in all specimens was 23.89 mm.


CONCLUSIONS
Hamstring graft fixation with a cross-pin system from the anteromedial portal with a 30-mm femoral tunnel presents a higher risk of injury to the LCL. The femoral tunnel should be drilled as long as possible.


CONCLUSIONS
A long femoral tunnel is required for safe transverse femoral fixation in an anatomical ACL reconstruction.
Gelber
Pablo Eduardo
PE
Department of Orthopaedic Surgery, Hospital de Sant Pau, Universitat Autònoma de Barcelona, C/Sant Antoni Maria Claret, 167, 08025 Barcelona, Spain. pablogelber@gmail.com
Reina
Francisco
F
Torres
Raúl
R
Monllau
Juan Carlos
JC
D000368:Aged; D000369:Aged, 80 and over; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D001182:Arthroscopy; D002102:Cadaver; D017885:Collateral Ligaments / Q000293:injuries; D004210:Dissection; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D007718:Knee Injuries / Q000517:prevention & control; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D019637:Orthopedic Procedures / Q000009:adverse effects / Q000379:methods*; D053441:Suture Anchors / Q000009:adverse effects; D013710:Tendons / Q000637:transplantation*