Starch et al. (A-18) wanted to show the effectiveness of a central four-quadrant sleeve and screw in anterior cruciate ligament reconstruction. The researchers performed a series of reconstructions on eight cadaveric knees. The following table shows the loads (in newtons) required to achieve different graft laxities (mm) for seven specimens (data not available for one specimen) using five different load weights. Graft laxity is the separation (in mm) of the femur and the tibia at the points of graft fixation.

Is there sufficient evidence to conclude that different loads are required to produce different levels of graft laxity? Let a ¼ :05.
Graft Laxity (mm)
Specimen 1 2345 1 297.1 297.1 297.1 297.1 297.1 2 264.4 304.6 336.4 358.2 379.3 3 188.8 188.8 188.8 188.8 188.8 4 159.3 194.7 211.4 222.4 228.1 5 228.2 282.1 282.1 334.8 334.8 6 100.3 105.0 106.3 107.7 108.7 7 116.9 140.6 182.4 209.7 215.4 Source: David W. Starch, Jerry W. Alexander, Philip C. Noble, Suraj Reddy, and David M.
Lintner, “Multistranded Hamstring Tendon Graft Fixation with a Central Four-Quadrant or a Standard Tibial Interference Screw for Anterior Cruciate Ligament Reconstruction,”
American Journal of Sports Medicine, 31 (2003), 338–344.