RESUMO
STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To characterize the timing of complications after spinal fusion procedures. SUMMARY OF BACKGROUND DATA: Despite many publications on risk factors for complications after spine surgery, there are few publications on the timing at which such complications occur. METHODS: Patients undergoing anterior cervical decompression and fusion (ACDF) or posterior lumbar fusion (PLF; with or without interbody) procedures during 2011-2013 were identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. For each of 8 different complications, the median time from surgery until complication was determined, along with the interquartile range and middle 80%. RESULTS: A total of 12,067 patients undergoing ACDF and 11,807 patients undergoing PLF were identified. For ACDF, the median day of diagnosis (and interquartile range; middle 80%) for anemia requiring transfusion was 0 (0-1; 0-2), myocardial infarction 2 (1-5; 0-15), pneumonia 4 (2-9; 1-14), pulmonary embolism 5 (2-9; 1-10), deep vein thrombosis 10.5 (7-16.5; 5-21), sepsis 10.5 (4-18; 1-23), surgical site infection 13 (8-19; 5-25), and urinary tract infection 17 (8-22; 4-26). For PLF, the median day of diagnosis (and interquartile range; middle 80%) for anemia requiring transfusion was 0 (0-1; 0-2), myocardial infarction 2 (1-4; 1-8), pneumonia 4 (2-9; 1-17), pulmonary embolism 5 (3-11; 2-17), urinary tract infection 7 (4-14; 2-23), deep vein thrombosis 8 (5-16; 3-20), sepsis 9 (4-16; 2-22), and surgical site infection 17 (13-22; 9-27). CONCLUSION: These precisely described postoperative time periods enable heightened clinical awareness among spine surgeons. Spine surgeons should have the lowest threshold for testing for each complication during the time period of greatest risk. Authors, reviewers, and surgeons utilizing research on postoperative complications should carefully consider the impact that the duration of follow-up has on study results. LEVEL OF EVIDENCE: 3.
Assuntos
Descompressão Cirúrgica/efeitos adversos , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/etiologia , Fusão Vertebral/efeitos adversos , Cirurgiões , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/etiologia , Estudos Retrospectivos , Fatores de Risco , Fusão Vertebral/métodos , Fatores de Tempo , Adulto JovemRESUMO
STUDY DESIGN: Survey of spine surgeons and biomechanical comparison of screw pullout forces. OBJECTIVE: To investigate what may be a suboptimal practice regularly occurring in spine surgery. SUMMARY OF BACKGROUND DATA: In order for a tap to function in its intended manner, the pitch of the tap should be the same as the pitch of the screw. Undertapping has been shown to increase the pullout force of pedicle screws compared with line-to-line tapping. However, given the way current commercial lumbar pedicle screw systems are designed, undertapping may result in a tap being used that has a different pitch from that of the screw (incongruent pitch). METHODS: A survey asked participants questions to estimate the proportion of cases each participant performed in the prior year using various hole preparation techniques. Participant responses were interpreted in the context of manufacturing specifications of specific instrumentation systems. Screw pullout forces were compared between undertapping with incongruent pitch and undertapping with congruent pitch using 0.16 g/cm polyurethane foam block and 6.5-mm screws. RESULTS: Of the 3679 cases in which participants reported tapping, participants reported line-to-line tapping in 209 cases (5%), undertapping with incongruent pitch in 1156 cases (32%), and undertapping with congruent pitch in 2314 cases (63%). The mean pullout force for undertapping with incongruent pitch was 56 N (8%) less than the mean pullout force for undertapping with congruent pitch. This is equivalent to 13 lb. CONCLUSION: This study estimates that for about 1 out of every 3 surgical cases with tapping of lumbar pedicle screws in the United States, hole preparation is being performed by undertapping with incongruent pitch. This study also shows that undertapping with incongruent pitch results in a decrease in pullout force by 8% compared with undertapping with congruent pitch. Steps should be taken to correct this suboptimal practice. LEVEL OF EVIDENCE: 3.