A multicenter retrospective study was conducted. For a study, the researchers sought to determine the primary postoperative problems associated with Scheuermann kyphosis (SK) versus adolescent idiopathic scoliosis (AIS) in a large group that was matched by demographics, levels fused, and operational method. Between 2006 and 2018, AIS patients were compared to SK patients in real-time. About 6 surgeons from 2 institutions performed all of the procedures. It was calculated how many complications and adjustments there would be. A sub-analysis matched by levels fused solely in 1-to-1 matched pairs was done to compare SK and AIS patients by age, sex, and levels fused in 1-to-1 matched pairings. Total 1,322 patients were looked at (1222 AIS; 100 SK). The AIS group had 52 (4.3%) complications compared to 20 (20%) in the SK group (P<0.001), with infections and revisions accounting for the majority of complication rates in both cohorts. When the AIS and SK groups were matched by age, sex, and levels fused, the AIS group had 8 problems and the SK group had 11 (P=0.63), with infection and revision rates similar (P=0.29) and (P=0.26), respectively. EBL, surgical duration, and complication rates remained similar when amounts fused solely were matched (P>0.05). In contrast to past research, the outcomes showed that postoperative complication rates (i.e., infection and revision rates) were not substantially different between SK and AIS patients in a matched cohort.