Post operative outcomes of tunnel orientation in post operative ACL reconstruction patients - MRI based study

ACL reconstruction has evolved over the years into a more anatomical technique so as to replicate the original ACL origin and insertion. Tunnel position has taken preponderance in recent times as it has been identified as one of the most important aspect of the procedure that determines outcomes .Outcomes have been measured on the basis of patient-reported outcome measures, stability of the knee, and activity levels. Tunnel position has been found to be an important variable in these outcomes. Tunnel positions can be assessed via X-ray and computed tomography (CT) scan with CT being potentially more accurate as it gives a three-dimensional picture of the femoral and tibial tunnel apertures. There have been studies done in the past to assess femur and tibial tunnels positions in various techniques of doing ACL reconstructions. Femoral tunnel position has been shown to influence patient-reported outcomes more than the tibial tunnel position.  Tunnel malposition is an iatrogenic complication and studies have been done in the past which showed that when viewing the femoral footprint end on while drilling the femoral tunnel produced tunnels that were more anatomic, but it was not statistically significant.

The ultimate result of a surgery is measured by the patients return to activity and pre-operative functional levels that may be different for different individuals. However, instrumented objective methods can also be used to measure stability of individual ligaments. Studies in the past have shown that even though there may not be statistically significant differences in the objective arthrometric measurement before and after surgery, subjective scores do show a significant improvement

The age and BMI of the patients did not seem to affect outcomes, as most of  the patients were of a similar age group and there were no obese patients in this subset. There was no statistically significant difference in the age and BMI of patients in the tunnel groups compared. Patients that had their operation within 3 months of their injury had better IKDC and hop test scores. This could be attributed to the fact that lesser injuries to surrounding structures or their capacity to heal are better when operated upon early. A chronic ACL deficient knee may lead to degenerative changes and injury to secondary stabilizers over a period of time worsening outcomes.Meniscus surgery did not seem to affect outcomes as in most cases, there was either no meniscus surgery or they were repaired, that to preserve the biomechanics of the knee. The minority of cases that had a partial meniscectomy was smaller in number and could be a possible reason for not influencing outcomes. Also, the follow-up was for 34 months, longer follow-up might be necessary to conclusively identify the role of meniscus surgery on outcomes. Studies in the past have used CT and X-rays to measure tunnel positions as well as outcome measures for stability and PROM’s post-ACL reconstruction.

The primary objective of my study is to assess post operative MRI findings with functional outcomes in patients undergoing arthroscopic ACL reconstruction