Functional Anterior Knee Pain and Return to Sport Following Bone-Patellar Tendon-Bone Anterior Cruciate Ligament Reconstruction

Background: Bone-patellar tendon-bone (BPTB) anterior cruciate ligament (ACL) reconstruction is a frequently used technique but has been associated with a high incidence of postoperative anterior knee pain. However, previous studies have not evaluated if this anterior knee pain is functionally limiting for patients. This study introduces the concept of functional anterior knee pain, or kneecap pain that limits patients' ability to return to their prior level of activity or sport. Methods: We reviewed BPTB ACL reconstructions from April 2013 to May 2017. Patients included in the analysis had a minimum of 1 year of clinical follow-up and 3 years of survey follow-up. Statistical analyses were performed using paired t tests and binomial test. Results: Sixty-seven patients met the inclusion criteria. Compared to the mean preoperative visual analog scale (VAS) pain score of 6.1, patients reported statistically significant reductions in VAS scores at 1 year and 3 years postoperatively to 0.9 and 1.8, respectively (P<0.01). The incidence (28.4%) of anterior knee pain was highest at the 3-month time point. This incidence decreased to 6.0% at 1 year and 7.5% at 3 years postoperatively. At 3 years postoperatively, 94% (63/67) of the patients in this study were not limited by functional anterior knee pain and returned to preoperative levels of activity and sport. Conclusion: To our knowledge, this investigation is the first to define and quantify the relationship between postoperative anterior knee pain and resultant functional limitations. This study shows that ACL reconstruction with BPTB autograft was not significantly associated with functional anterior knee pain in our population and that the incidence of postoperative anterior knee pain following BPTB ACL reconstruction may be less than previously reported.