COMPARISON OF CONTINUOUS ADDUCTOR CANAL AND FEMORAL NERVE BLOCKS FOR ANALGESIA AND SPORTS READINESS AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION IN ADOLESCENT PATIENTS

BACKGROUND: Continuous femoral nerve blocks (cFNB) have become a popular method for post-operative analgesia for patients undergoing anterior cruciate ligament reconstruction (ACLR). However, early weight-bearing and the return of quadriceps function favor a motor sparing block, such as a continuous adductor canal nerve block (cACB). HYPOTHESIS/PURPOSE: We retrospectively compared cACB to cFNB in adolescent patients undergoing ACLR, assessing early post-operative pain scores, narcotic usage, and patient satisfaction; and return of quadriceps function and sports readiness at six months post-surgery. We hypothesized that cACB compared to cFNB would result in in a greater likelihood of sports readiness at six months without having compromised analgesia in the early post-operative period. METHODS: We retrospectively reviewed a consecutive series of adolescent patients who underwent ACLR between January 2016 and September 2018 and received either a cACB or cFNB for post-operative pain management. Patient demographic and surgical data, post-operative pain scores, opioid consumption, satisfaction and complications, dates and results of the Return to Sports (RTS) evaluations were collected from the medical record. Comparisons of categorical and continuous variables between groups were made using the χ (2) test, Spearman correlation test, and one-way ANOVA with Bonferroni adjustment. RESULTS: Ninety-one patients (53 with cFNB, 38 with cACB) were reviewed for post-operative analgesia outcomes and quadriceps function at six months and beyond. Analysis of demographic and surgical data revealed no difference in the make-up of the two groups. There were no significant differences between groups in the total oxycodone use PODs 1-3 (p = 0.213), daily post-operative pain scores (p > 0.25), or satisfaction with the blocks (p = 0.93). There was no difference in time to RTS nor in the percentage of patients who achieved a 90% limb symmetry index for quadriceps strength when comparing the two groups at the six-month mark and beyond (p = 0.384). CONCLUSIONS: We found no difference in post-operative analgesic requirements and high satisfaction in both groups when comparing patients who underwent ACLR with hamstring autograft with a cACB to those who underwent a similar procedure with a cFNB. Readiness for return to sports and return of quadriceps function at six months and beyond does not appear to vary with regional technique, either cACB or cFNB, employed at surgery.