Anterior cruciate ligament reconstruction: Effect of graft tunnel position on early to mid-term clinical outcomes

Abstract

BACKGROUND Patient reported outcome measures (PROMs) can be used to assess knee function following anterior cruciate ligament (ACL) reconstruction. Intra-operatively, femoral and tibial tunnels are created to accommodate the new ACL graft. It is postulated that there is an optimum position and orientation of these tunnels and that outcomes from this procedure are affected by their position. AIM To evaluate the influence of graft tunnel position on early to mid-term clinical outcomes following ACL reconstruction. METHODS Six PROMs were collected following ACL reconstruction which included the Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee, Lysholm, Tegner, EuroQol-5 Dimension-5 level, and Short Form 12-item Health Survey. A total of 8 radiological parameters were measured from post-operative X-rays relating to graft tunnel positions. This data was analysed to assess for any correlations between graft tunnel position and post-operative PROMs. RESULTS A total of 87 patients were included in the study with a mean post-operative follow-up of 2.3 years (range 1 to 7 years). Posterior position of tibial tunnel was associated with improved KOOS quality of life (rho = 0.43, P = 0.002) and EQ-5D VAS (rho = 0.36, P = 0.010). Anterior position of EndoButton femoral tunnel was associated with an improved EQ-5D index (rho = -0.38, P = 0.028). There were no other significant correlations between any of the other radiological parameters and PROM scores. CONCLUSION Overall, graft tunnel position had very little correlation with clinical outcomes following ACL reconstruction. A few (posterior) tibial tunnel and (anterior) EndoButton femoral tunnel measurements were associated with better PROMs.