Surgical site infection is a major risk factor of pseudarthrosis in adult spinal deformity surgery

Published:September 05, 2022DOI:



      Despite the evidence in appendicular skeletal surgery, the effect of infection on spinal fusion remains unclear, particularly after Adult Spinal Deformity (ASD) surgery.


      The purpose of this study was to determine the impact of surgical site infection (SSI) in ASD surgery fusion rates and its association with other risks factors of pseudarthrosis.


      We conducted an international multicenter retrospective study on a prospective cohort of patients operated for spinal deformity.


      A total of 956 patients were included (762 females and 194 males).


      Patient's preoperative characteristics, pre and postoperative spinopelvic parameters, surgical variables, postoperative complications and were recorded. Surgical site infections were asserted in case of clinical signs associated with positive surgical samples. Each case was treated with surgical reintervention for debridement and irrigation. Presence of pseudarthrosis was defined by the association of clinical symptoms and radiological signs of nonfusion (either direct evidence on CT-scan or indirect radiographic clues such as screw loosening, rod breakage, screw pull out or loss of correction). Each iterative surgical intervention was collected.


      Univariate and multivariate analysis with logistic regression models were performed to evaluate the role of risk factors of pseudarthrosis.


      Nine hundred fifty-six surgical ASD patients with more than two years of follow-up were included in the study. 65 of these patients were treated for SSI (6.8%), 138 for pseudarthrosis (14.4%), and 28 patients for both SSI and pseudarthrosis.
      On multivariate analysis, SSI was found to be a major risk factor of pseudarthrosis (OR=4.4; 95% CI=2.4,7.9) as well as other known risks factors: BMI (OR=1.1; 95% CI=1.0,1.1), smoking (OR=1.6; 95% CI=1.1,2.9), performance of Smith-Petersen osteotomy (OR = 1.6; 95% CI 1.0,2.6), number of vertebrae instrumented (OR=1.1; 95% CI=1.1,1.2) and the caudal level of fusion, with a distal exponential increment of the risk (OR max for S1=6, 95% CI=1.9,18.6).


      SSI significantly increases the risk of pseudarthrosis with an OR of 4.4.


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        • Weistroffer JK
        • Perra JH
        • Lonstein JE
        • Schwender JD
        • Garvey TA
        • Transfeldt EE
        • et al.
        Complications in long fusions to the sacrum for adult scoliosis: minimum five-year analysis of fifty patients.
        Spine (Phila Pa 1976). 2008; 33: 1478-1483
        • Pitter FT
        • Lindberg-Larsen M
        • Pedersen AB
        • Dahl B
        • Gehrchen M.
        Revision risk after primary adult spinal deformity surgery: a nationwide study with two-year follow-up.
        Spine Deform. 2019; 7 (.e2): 619-626
        • Zhu F
        • Bao H
        • Liu Z
        • Bentley M
        • Zhu Z
        • Ding Y
        • et al.
        Unanticipated revision surgery in adult spinal deformity: an experience with 815 cases at one institution.
        Spine (Phila Pa 1976). 2014; 39: B36-B44
        • Mok JM
        • Cloyd JM
        • Bradford DS
        • Hu SS
        • Deviren V
        • Smith JA
        • et al.
        Reoperation after primary fusion for adult spinal deformity: rate, reason, and timing.
        Spine (Phila Pa 1976). 2009; 34: 832-839
        • Fanous AA
        • Kolcun JPG
        • Brusko GD
        • Paci M
        • Ghobrial GM
        • Nakhla J
        • et al.
        Surgical site infection as a risk factor for long-term instrumentation failure in patients with spinal deformity: a retrospective cohort study.
        World Neurosurg. 2019; 132: e514-e519
        • How NE
        • Street JT
        • Dvorak MF
        • Fisher CG
        • Kwon BK
        • Paquette S
        • et al.
        Pseudarthrosis in adult and pediatric spinal deformity surgery: a systematic review of the literature and meta-analysis of incidence, characteristics, and risk factors.
        Neurosurg Rev. 2019; 42: 319-336
        • Shillingford JN
        • Laratta JL
        • Reddy H
        • Ha A
        • Lehman RA
        • Lenke LG
        • et al.
        Postoperative surgical site infection after spine surgery: an update from the scoliosis research society (SRS) morbidity and mortality database.
        Spine Deform. 2018; 6: 634-643
        • Soroceanu A
        • Burton DC
        • Oren JH
        • Smith JS
        • Hostin R
        • Shaffrey CI
        • et al.
        Medical complications after adult spinal deformity surgery: incidence, isk factors, and clinical impact.
        Spine (Phila Pa 1976). 2016; 41: 1718-1723
        • Haddad S
        • Núñez-Pereira S
        • Pigrau C
        • Rodríguez-Pardo D
        • Vila-Casademunt A
        • Alanay A
        • et al.
        The impact of deep surgical site infection on surgical outcomes after posterior adult spinal deformity surgery: a matched control study.
        Eur Spine J. 2018; 27: 2518-2528
        • Andrés-Cano P
        • Cerván A
        • Rodríguez-Solera M
        • Antonio Ortega J
        • Rebollo N
        • Guerado E
        Surgical infection after posterolateral lumbar spine arthrodesis: CT analysis of spinal fusion.
        Orthop Surg. 2018; 10: 89-97
        • Yadla S
        • Maltenfort MG
        • Ratliff JK
        • Harrop JS.
        Adult scoliosis surgery outcomes: a systematic review.
        Neurosurg Focus. 2010; 28: E3
        • Bradford DS
        • Tay BK
        • Hu SS.
        Adult scoliosis: surgical indications, operative management, complications, and outcomes.
        Spine (Phila Pa 1976). 1999; 24: 2617-2629
        • Hollern DA
        • Woods BI
        • Shah NV
        • Schroeder GD
        • Kepler CK
        • Kurd MF
        • et al.
        Risk factors for pseudarthrosis after surgical site infection of the spine.
        Int J Spine Surg. 2019; 13: 507-514
        • Shen FH
        • Mason JR
        • Shimer AL
        Arlet VM. Pelvic fixation for adult scoliosis.
        Eur Spine J. 2013; 22: S265-S275
        • Cho W
        • Mason JR
        • Smith JS
        • Shimer AL
        • Wilson AS
        • Shaffrey CI
        • et al.
        Failure of lumbopelvic fixation after long construct fusions in patients with adult spinal deformity: clinical and radiographic risk factors: clinical article.
        J Neurosurg Spine. 2013; 19: 445-453
        • Kim YJ
        • Bridwell KH
        • Lenke LG
        • Cho K-J
        • Edwards CC
        • Rinella AS.
        Pseudarthrosis in adult spinal deformity following multisegmental instrumentation and arthrodesis.
        J Bone Joint Surg Am. 2006; 88: 721-728
        • Joaquim AF
        • Helvie P
        • Patel AA.
        Bariatric surgery and low back pain: a systematic literature review.
        Global Spine J. 2020; 10: 102-110
        • Goyal A
        • Elminawy M
        • Kerezoudis P
        • Lu VM
        • Yolcu Y
        • Alvi MA
        • et al.
        Impact of obesity on outcomes following lumbar spine surgery: a systematic review and meta-analysis.
        Clin Neurol Neurosurg. 2019; 177: 27-36
        • Islam NC
        • Wood KB
        • Transfeldt EE
        • Winter RB
        • Denis F
        • Lonstein JE
        • et al.
        Extension of fusions to the pelvis in idiopathic scoliosis.
        Spine (Phila Pa 1976). 2001; 26: 166-173
        • Singh D
        • Park W
        • Hwang D
        • Levy MS.
        Severe obesity effect on low back biomechanical stress of manual load lifting.
        Work. 2015; 51: 337-348
        • Greco EA
        • Fornari R
        • Rossi F
        • Santiemma V
        • Prossomariti G
        • Annoscia C
        • et al.
        Is obesity protective for osteoporosis? Evaluation of bone mineral density in individuals with high body mass index.
        Int J Clin Pract. 2010; 64: 817-820
        • Okuyama K
        • Abe E
        • Suzuki T
        • Tamura Y
        • Chiba M
        • Sato K
        Influence of bone mineral density on pedicle screw fixation: a study of pedicle screw fixation augmenting posterior lumbar interbody fusion in elderly patients.
        Spine J. 2001; 1: 402-407
        • Wing KJ
        • Fisher CG
        • O'Connell JX
        • Wing PC
        Stopping nicotine exposure before surgery. The effect on spinal fusion in a rabbit model.
        Spine (Phila Pa 1976). 2000; 25: 30-34
        • Grubb SA
        • Lipscomb HJ
        • Suh PB.
        Results of surgical treatment of painful adult scoliosis.
        Spine (Phila Pa 1976). 1994; 19: 1619-1627
        • Aleem IS
        • Tan LA
        • Nassr A
        • Riew KD.
        Surgical site infection prevention following spine surgery.
        Global Spine J. 2020; 10: 92S-98S
        • Smith JS
        • Shaffrey E
        • Klineberg E
        • Shaffrey CI
        • Lafage V
        • Schwab FJ
        • et al.
        Prospective multicenter assessment of risk factors for rod fracture following surgery for adult spinal deformity.
        J Neurosurg Spine. 2014; 21: 994-1003
        • Barton C
        • Noshchenko A
        • Patel V
        • Cain C
        • Kleck C
        • Burger E.
        Risk factors for rod fracture after posterior correction of adult spinal deformity with osteotomy: a retrospective case-series.
        Scoliosis. 2015; 10: 30
        • Kim HJ
        • Boachie-Adjei O
        • Shaffrey CI
        • Schwab F
        • Lafage V
        • Bess S
        • et al.
        Upper thoracic versus lower thoracic upper instrumented vertebrae endpoints have similar outcomes and complications in adult scoliosis.
        Spine (Phila Pa 1976). 2014; 39: E795-E799
        • Riouallon G
        • Bouyer B
        • Wolff S.
        Risk of revision surgery for adult idiopathic scoliosis: a survival analysis of 517 cases over 25 years.
        Eur Spine J. 2016; 25: 2527-2534
        • Croes M
        • van der Wal BCH
        • Vogely HC.
        Impact of bacterial infections on osteogenesis: evidence from in vivo studies.
        J Orthop Res. 2019; 37: 2067-2076
        • Santolini E
        • West R
        • Giannoudis PV.
        Risk factors for long bone fracture non-union: a stratification approach based on the level of the existing scientific evidence.
        Injury. 2015; 46: S8-19
        • Agarwal A
        • Mooney M
        • Agarwal AG
        • Jayaswal D
        • Saakyan G
        • Goel V
        • et al.
        High prevalence of biofilms on retrieved implants from aseptic pseudarthrosis cases.
        Spine Surg Relat Res. 2021; 5: 104-108
        • Agarwal A
        • Kelkar A
        • Agarwal AG
        • Jayaswal D
        • Schultz C
        • Jayaswal A
        • et al.
        Implant retention or removal for management of surgical site infection after spinal surgery.
        Global Spine J. 2020; 10: 640-646