Grading of complications after cervical deformity-corrective surgery: Are existing classification systems applicable?

Study Design:This is a retrospective review of prospective multicenter cervical deformity (CD) database.Objective:Assess the impact of complication type and Clavien complication (Cc) grade on clinical outcomes of surgical CD patientsBackground:Validated for general surgery the Clavien-Dindo complication classification system allows for broad comparison of postoperative complications; however the applicability of this system is unclear in CD-specific populations.Methods:Surgical CD patients above 18 years with baseline and postoperative clinical data were included. Primary outcomes were complication type (renal infection cardiac pulmonary gastrointestinal neurological musculoskeletal implant-related radiographic operative wound) and Cc grade (I II III IV V). Secondary outcomes were estimated blood loss (EBL) length of stay (LOS) reoperation and health-related quality of life (HRQL) score. The univariate analysis assessed the impact of complication type and Cc grade on improvement markers and 1-year postoperative HRQL outcomes.Results:In total 153 patients (61±10 y 61% female) underwent surgery for CD (8.1±4.6 levels fused; surgical approach included 48% posterior 18% anterior 34% combined). Overall 63% of patients suffered at least 1 complication. Complication breakdown by type: renal (2.0%) infection (5.2%) cardiac (7.2%) pulmonary (3.9%) gastrointestinal (2.0%) neurological (26.1%) musculoskeletal (0.0%) implant-related (3.9%) radiographic (16.3%) operative (7.8%) and wound (5.2%). Of complication types only operative complications were associated with increased EBL (P=0.004) whereas renal cardiac pulmonary gastrointestinal neurological radiographic and wound infections were associated with increased LOS (P<0.050). Patients were also assessed by Cc grade: I (28%) II (14.3%) III (16.3%) IV (6.5%) and V (0.7%). Grades I and V were associated with increased EBL (both P<0.050); Cc grade V was the only complication not associated with increased LOS (P=0.610). Increasing complication severity was correlated with increased risk of reoperation (r=0.512; P<0.001) but not inferior 1-year HRQL outcomes (all P>0.05).Conclusions:Increasing complication severity assessed by the Clavien-Dindo classification system was not associated with increased EBL inpatient LOS or inferior 1-year postoperative HRQL outcomes. Only operative complications were associated with increased EBL. These results suggest a need for modification of the Clavien system to increase applicability and utility in CD-specific populations.