Anterior cervical discectomy and fusion: is surgical education safe?

Operative skills are key to neurosurgical resident training. They should be acquired in a structured manner and preferably starting early in residency. The aim of this study was to test the hypothesis that the outcome and complication rate of anterior cervical discectomy and fusion with or without instrumentation (ACDF(I)) is not inferior for supervised residents as compared to board-certified faculty neurosurgeons (BCFN).

This was a retrospective single-center study of all consecutive patients undergoing ACDF(I)-surgery between January 2011 and August 2014. All procedures were dichotomized into two groups according to the surgeon's level of experience: teaching cases (postgraduate year (PGY)-2 to PGY-6 neurosurgical residents) and non-teaching cases operated by BCFN. The primary study endpoint was patients' clinical outcome 4 weeks after surgery, categorized into a binary responder and non-responder variable. Secondary endpoints were complications, need for re-do surgery, and clinical outcome until the last follow-up.

After exclusion of six cases because of incomplete data, a total of 287 ACDF(I) operations were enrolled into the study, of which 82 (29.2 %) were teaching cases and 199 (70.8 %) were non-teaching cases. Teaching cases required a longer operation time (131 min (95 % confidence interval (CI) 122-141 min) vs. 102 min (95-108 min; p < 0.0001) and were associated with a slightly higher estimated blood loss (84 ml (95 % CI 56-111 ml) vs. 57 ml (95 % CI 47-66 ml); p = 0.0017), while there was no difference in the rate of intraoperative complications (2.4 vs. 1.5 %; p = 0.631). Four weeks after surgery, 92.7 and 93 % of the patients had a positive response to surgery (p = 1.000), respectively. There was no difference in the postoperative complication rate (4.9 vs. 3.0 %; p = 0.307). Around 30 % of the study patients were followed up in outpatient clinics for more than once up until a mean period of 6.4 months (95 % CI 5.3-7.6 months). At the last follow-up, the clinical outcome was similar with a 90 % responder rate for both groups (p = 0.834). In total, five patients from the teaching group and eight patients from the non-teaching group required re-do surgery (p = 0.602).

Short- and mid-term outcomes and complication rates following microscopic ACDF(I) were comparable for patients operated on by supervised neurosurgical residents or by senior surgeons. Our data thus indicate that a structured neurosurgical education of operative skills does not lead to worse outcomes or increase the complication rates after ACDF(I). Confirmation of the results by a prospective study is desired.