Primary Versus Revision Spinal Fusion in Children: An Analysis of 74,525 Cases From the Nationwide Inpatient Sample

Incidental dural tears during pediatric posterior spinal fusions

PURPOSE

To characterize the frequency of incidental dural tears in pediatric spine surgery, their treatment, complications, and results of long-term follow-up.

METHODS

A retrospective review of all pediatric patients who underwent a posterior spinal fusion (PSF) between 2004-2019 at a tertiary children's hospital was conducted. Electronic medical records were reviewed for patient demographics, intra-operative data, presence of an incidental dural tear, repair method, and patient outcomes.

RESULTS

3043 PSFs were reviewed, with 99 dural tears identified in 94 patients (3.3% overall incidence). Mean follow-up was 35.7 months (range 0.1-142.5). When the cause of the dural tear was specified, 69% occurred during exposure, 5% during pedicle screw placement, 4% during osteotomy, 2% during removal of implants, and 2% during intra-thecal injection of morphine. The rate of dural tears during primary PSF was significantly lower than during revision PSF procedures (2.6% vs. 6.2%, p < 0.05). 86.9% of dural tears were repaired and/or sealed intraoperatively, while 13.1% had spontaneous resolution. Postoperative headaches developed in 13.1% of patients and resolved at a mean of 7.6 days. There was no difference in the incidence of headaches in patients that were ordered bedrest vs. no bedrest (p > 0.99). Postoperative infections occurred in 9.5% of patients and 24.1% patients were identified to have undergone a revision surgery.

CONCLUSIONS

Incidence of intra-operative dural tears in pediatric spine surgery is 3.3%. Although complications associated with the dural tear occur, most resolve over time and there were no long-term sequelae in patients with 2 years of follow up.

LEVEL OF EVIDENCE

Level IV.

Incidence and causes of instrument-related complications after primary definitive fusion for pediatric spine deformity

OBJECTIVE

Various complications have been reported in the treatment of pediatric spinal deformities. Among these, instrument-related complications could be critical concerns and risks of reoperation. This study aimed to identify the incidence and causes of complications after primary definitive fusion for pediatric spine deformities.

METHODS

The authors retrospectively collected data from 14 institutions about patients who underwent primary definitive fusion between 2015 and 2017. There were 1490 eligible patients (1184 female and 306 male), with a mean age of 13.9 years. The incidence, causes, and reoperation rates were analyzed according to 4 etiologies of pediatric spine deformity (congenital, neuromuscular, syndromic, idiopathic). The complications were also categorized as screw-, hook-, or rod-related complications, implant loosening or backout, and junctional problems.

RESULTS

The incidence of overall instrument-related complications was 5.6% (84 cases). Regarding etiology, the incidence rates were 4.3% (idiopathic), 6.8% (syndromic), 7.9% (congenital), and 10.4% (neuromuscular) (p < 0.05). The most common causes were pedicle screw malposition (60.7%), followed by implant backout or loosening (15.4%), junctional problems (13.1%), rod breakage (4.8%), and other complications (6.0%). Univariate analysis showed that etiology, type of deformity (kyphosis), surgical procedure, operation time, and estimated blood loss were significant factors. Multivariate analysis revealed that etiology (neuromuscular), surgical procedure (combined approach), and operation time (> 5 hours) remained as significant risk factors. Among all patients with instrument-related complications, 45% (38/84) required revision surgery. Of these cases, > 50% were related to pedicle screw malposition. Medial breach was the most common complication regardless of location, from upper thoracic to lumbar spine.

CONCLUSIONS

Pedicle screw malposition was the primary cause of overall complications and subsequent reoperation. In addition to more precise screw insertion techniques, meticulous confirmation of pedicle screw placement, especially of medial breach, may reduce the overall instrument-related complications and revision rates.

Incidence and Risk Factors for Unplanned Return to the Operating Room Following Primary Definitive Fusion for Pediatric Spinal Deformity: A Multicenter Study with Minimum 2-year Follow-Up

STUDY DESIGN

A retrospective multicenter cohort study.

OBJECTIVE

The aim of this study was to identify the incidence and risk factors for UPROR within minimum 2-year follow-up in primary definitive fusion for pediatric spinal deformity.

SUMMARY OF BACKGROUND DATA

Several previous reports have elucidated the incidence of complications after pediatric scoliosis surgery; however, there has been no study that described the incidence and risk factors for unplanned return to the operating room (UPROR) with long-term follow-up in surgery for pediatric scoliosis with every etiology.

METHODS

We retrospectively extracted data of patients aged <19 years, from 14 institutes in Japan, who underwent primary definitive fusion surgery for spinal deformity between January 1, 2015 and December 31, 2017. The primary outcomes were the incidence of UPROR within the minimum 2-year follow-up period for any reason. Univariate and multivariate logistical analyses were conducted to identify potential risk factors associated with UPROR.

RESULTS

We identified 1417 eligible patients (287 males and 1130 females) with a mean age of 13.9 years. UPROR for any reason within minimum 2-year follow-up was identified in 68 patients (4.8%). The most frequent cause for UPROR was implant failure found in 29 patients, followed by surgical site infection in 14 patients, junctional problems in 10 patients, and neurological complications in six patients. The multivariate logistic regression analysis revealed that a diagnosis of kyphosis (odds ratio [OR], 2.65; 95% confidence interval [CI] 1.16-6.04), etiology of congenital or structural type (OR 2.21; 95% CI 1.08-4.53), etiology of syndromic type (OR 2.67; 95% CI 1.27-5.64), and increased operation time of ≥300 minutes (OR 1.81; 95% CI 1.07-3.07) were the risk factors for the incidence of UPROR.

CONCLUSION

The present multicenter study identified for the first time the incidence and risk factors for UPROR with minimum 2-year follow-up after primary definitive fusion surgery for pediatric spinal deformity with every etiology.Level of Evidence: 3.

Revision risk after pediatric spinal deformity surgery: a nationwide study with 2-year follow-up

BACKGROUND CONTEXT

Revision risk after pediatric spine surgery is not well established and varies between deformity etiologies.

PURPOSE

To report the 2-year revision risk following surgery for primary pediatric spinal deformity in a nationwide cohort and to evaluate potential risk factors and reasons for revision surgery.

DESIGN

Retrospective nationwide cohort study.

PATIENT SAMPLE

A national registry study of all pediatric spinal deformity patients undergoing surgery during 2006-2015 (n=1310).

OUTCOME MEASURES

Two-year revision risk.

METHODS

All patients ≤21 years of age undergoing spinal deformity surgery in Denmark during 2006-2015 were identified by procedure and diagnosis codes in the Danish National Patient Registry (DNPR). Data on revision surgery were retrieved from the DNPR. Patients were categorized in six groups according to etiology. Medical records were reviewed for reason for revision in all patients. Potential risk factors for revision were assessed with multiple logistic regression analyses and included age, etiology, sex, Charlson comorbidity index (CCI), and growth-preserving treatment.

RESULTS

Patients were categorized according to etiology: idiopathic deformity (53%), neuromuscular deformity (23%), congenital/structural deformity (9%), spondylolisthesis (7%), Scheuermann's kyphosis (5%), and syndromic deformity (3%). Of 1,310 included patients, 9.2% underwent revision surgery within 2 years and 1.5% was revised more than once. Median time to revision was 203 (interquartile range 35-485) days. The multivariable logistic regression found significantly higher odds ratio (OR) for revision in patients with growth-preserving treatment (OR=5.1, 95% confidence interval [CI] 2.6-10.1), congenital deformity (OR=2.7, 95% CI 1.3-5.3), spondylolisthesis (OR=3.5, 95% CI 1.9-6.7), Scheuermann kyphosis (OR=3.9, 95% CI 1.9-8.3), and CCI score ≥3 (OR=2.5 95% CI 1.1-5.6). The most common reason for revision was implant failure (32.5%) followed by residual deformity and/or curve progression (15.8%).

CONCLUSIONS

In this nationwide study, the 2-year revision risk after primary pediatric spinal deformity surgery is 9.2%. Risk factors for revision are etiology of congenital deformity, spondylolisthesis, Scheuermann kyphosis as well as patients with growth-preserving treatment and higher CCI. The most common reason for revision is implant failure.

Does Three-Dimensional Printed Patient-Specific Templates Add Benefit in Revision Surgeries for Complex Pediatric Kyphoscoliosis Deformity with Sublaminar Wires in Situ? A Clinical Study

STUDY DESIGN

Case-control study.

PURPOSE

To evaluate the accuracy of three-dimensional (3D) printed patient-specific templates (PSTs) for placement of pedicle screws (PAs) in patients undergoing revision surgeries for complex kyphoscoliosis deformity with sublaminar wires in situ.

OVERVIEW OF LITERATURE

Revision kyphoscoliosis correction surgery in pediatric patients is a challenging task for the treating surgeon. In patients with sublaminar wires in situ, the native anatomical landmarks are obscured, thus making the freehand screw placement technique a highly specialized task. Hence, the concept of using PSTs for insertion of PAs in such surgeries is always intriguing and attractive.

METHODS

Five consecutive patients undergoing revision deformity correction with sublaminar wires in situ were included in this study. Patients were divided in two groups based on the technique of PA insertion. A total of 91 PAs were inserted using either a freehand technique (group A) or 3D printed templates (group B) (34 vs. 57). The placement of PAs was classified according to a postoperative computed tomography scan using Neo's classification. Perforation beyond class 2 (>2 mm) was termed as a misplaced screw. The average time required for the insertion of screws was also noted.

RESULTS

Mean age, surgical time, and blood loss were recorded. The change in mean Cobb's angle in both groups was also recorded. The difference in rates of misplaced screws was noted in group A and group B (36.21% vs. 2.56%); however, the mean number of misplaced PAs per patient in group A and group B was statistically insignificant (6.5±3.54 vs. 4.67±1.53, p =0.4641). The mean time required to insert a single PA was also statistically insignificant (120±28.28 vs. 90±30 seconds, p =0.3456).

CONCLUSIONS

Although 3D printed PSTs help to avoid the misplacement of PAs in revision deformity correction surgeries with sublaminar wires in situ, the mean number of misplaced screws per patient using this technique was found to be statistically insignificant when compared with the freehand technique in this study.

Predictors of a Non-home Discharge Destination Following Spinal Fusion for Adolescent Idiopathic Scoliosis (AIS)

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Analyze risk factors associated with a non-home discharge following spinal fusions in adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Current evidence is limited with regard to which patient-level and provider/hospital-level factors predict a non-home discharge disposition following spinal fusions in AIS. Identifying these factors can allow providers to identify which patients would ultimately require facility care and can be discharged early to these facilities to reduce hospital costs.

METHODS

The 2012 to 2016 American College of Surgeons-National Surgical Quality Improvement Program Pediatric database was queried using Current Procedural Terminology codes for posterior spinal fusions (22800, 22802, and 22804) and anterior spinal fusions (22808, 22810, and 22812). Patients were categorized into those receiving a posterior-only fusion, anterior-only fusion, and combined anterior-posterior fusion. Only patients aged 10 to 18 undergoing corrective surgery for idiopathic scoliosis were included in the study.

RESULTS

Out of a total of 8452 patients-90 (1.1%) were discharged to a destination other than home (skilled-care facility, separate acute care unit, and/or rehabilitation unit). Following multivariate analysis, children with a body mass index of 20 to 30 (P = 0.002) or >30 (P = 0.003), structural pulmonary abnormality (P = 0.030), past history of childhood cancer (P = 0.018), an ASA grade >II (P<0.001), undergoing a revision surgery versus a primary surgery (P = 0.039), a length of stay >4 days (P<0.001), and the occurrence of a predischarge complication (P = 0.003) were independent predictors associated with a non-home discharge disposition.

CONCLUSION

In the current era of evolving health-care in which there is an increased focus toward decreasing costs, providers should consider utilizing these data to preoperatively identify patients who can be discharged to facility, and tailor an appropriate postoperative course of care aimed at expediting discharge processes to curb the financial burden of a prolonged length of stay.

LEVEL OF EVIDENCE

3.

30-day Outcomes in Primary vs. Revision Posterior Spinal Fusion for Pediatric Spinal Deformity

OBJECTIVES

Current evidence, with regard to primary vs. revision spinal fusions in pediatric spine deformities, is limited to inpatient outcomes only. The current study aims to analyze and compare 30-day outcomes in pediatric spine deformity patients undergoing a primary vs. a revision posterior spinal fusion.

PATIENTS AND METHODS

The 2012-2016 American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) Pediatric database was queried using Current Procedural Terminology (CPT) codes for patients undergoing posterior spinal fusions (22800, 22802 and 22804). Patients undergoing concurrent anterior fusion/combined fusion and anterior-only fusions were removed from the study. Revision spinal fusions were captured using CPT codes for re-insertion of spinal fixation device (22830), exploration of spinal fusions (22849), 22850 and 22852 (removal of posterior instrumentation).

RESULTS

Out of a total of 13,398 patients, 332 (2.5%) underwent a revision posterior spinal fusion and the remained underwent primary spinal fusion. Following adjustment for baseline clinical characteristics, patients undergoing revision posterior spinal fusions were at a higher risk of deep surgical site infections (OR 2.43 [95% CI 1.10-5.35]; p = 0.028), organ/space surgical site infections (OR 4.09 [1.19-14.04]; p = 0.025) and 30-day unplanned re-operations (OR 1.87 [95% CI 1.17-3.00].

CONCLUSIONS

Pediatric spine deformity patients undergoing revision spinal fusions are at a higher risk of experiencing wound-complications and subsequent unplanned re-operations within 30-days of surgery. Providers should promote careful wound-care and/or awareness among care-givers to minimize the risks and costs associated with these specific adverse outcomes.

A National Analysis on Predictors of Discharge to Rehabilitation After Corrective Surgery for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Retrospective study of a national database.

OBJECTIVE

To identify the incidence and risk factors for discharge to a rehabilitation facility after corrective surgery for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

The vast majority of patients who undergo surgery for AIS are discharged home, with limited data on rates and causes for discharge to a rehabilitation facility.

METHODS

The United States National Inpatient Sample (NIS) database was queried for the years 2012 to 2014. Inclusion criteria were children aged 10 to 18 who underwent surgery for idiopathic scoliosis. Studied data included patient demographics, operative parameters, length of stay, and hospital charges. Perioperative complications were also examined, along with their association with discharge to an inpatient rehabilitation facility. Statistical analysis was performed via chi-squared testing and multivariate analysis, with significance defined as a P-value <0.05.

RESULTS

A total of 17,275 patients were included (76.3% female, mean age 14 yr). Out of the entire cohort, 4.8% of patients developed a complication and 0.6% were discharged to a rehabilitation facility. The most common complications included respiratory failure (2.3%), reintubation (0.8%), and postoperative hematoma (0.8%). Following multivariate analysis, male sex (Odds ratio (OR) 4.7; 95% Confidence Interval (CI), 1.8-12.2; P = 0.002), revision surgery (OR 29.6; 95% CI, 5.7-153.5; P < 0.001), and development of a perioperative complication (OR 12.3; 95% CI, 4.7-32.4; P < 0.001) were found to be significant predictors of discharge to rehabilitation. Average length of stay was 8 ± 6 versus 5 ± 3 days and hospital charges were $254,425 versus $186,273 in the complication and control groups, respectively (both P < 0.001).

CONCLUSION

Discharge to rehabilitation after AIS surgery is uncommon. However, patients who are male, undergo revision procedures, or develop a complication may have a higher risk of a non-routine discharge. Complication occurrence also resulted in significantly longer lengths of stay and healthcare costs.

LEVEL OF EVIDENCE

3.

Incidental durotomy in the pediatric spine population

OBJECTIVESpine surgery is less common in children than adults. These surgeries, like all others, are subject to complications such as bleeding, infection, and CSF leak. The rate of incidental durotomy in the pediatric population, and its associated complications, has scarcely been reported in the literature.METHODSThis is a retrospective chart review of all pediatric patients operated on at Wake Forest Baptist Health from 2012 to 2017 who underwent spine surgeries. The authors excluded any procedures with intended durotomy, such as tethered cord release or spinal cord tumor resection.RESULTSFrom 2012 to 2017, 318 pediatric patients underwent surgery for a variety of indications, including adolescent idiopathic scoliosis (51.9%), neuromuscular scoliosis (27.4%), thoracolumbar fracture (2.83%), and other non-fusion-related indications (3.77%). Of these patients, the average age was 14.1 years, and 71.0% were female. There were 6 total incidental durotomies, resulting in an overall incidence of 1.9%. The incidence was 18.5% in revision operations, compared to 0.34% for index surgeries. Comparison of the revision cohort to the durotomy cohort revealed a trend toward increased length of stay, operative time, and blood loss; however, the trends were not statistically significant. The pedicle probe was implicated in 3 cases and the exact cause was not ascertained in the remaining 3 cases. The 3 durotomies caused by pedicle probe were treated with bone wax; 1 was treated with dry Gelfoam application and 2 were treated with primary repair. Only 1 patient had a persistent leak postoperatively that eventually required wound revision.CONCLUSIONSIncidental durotomy is an uncommon occurrence in the pediatric spinal surgery population. The majority occurred during placement of pedicle screws, and they were easily treated with bone wax at the time of surgery. Awareness of the incidence, predisposing factors, and treatment options is important in preventing complications and disability.

In-hospital mortality and morbidity of pediatric scoliosis surgery in Japan: Analysis using a national inpatient database

Several previous reports have elucidated the mortality and incidence of complications after pediatric scoliosis surgery using nationwide databases. However, all of these studies were conducted in North America. Hence, this study aimed to identify the incidence and risk factors for in-hospital mortality and morbidity in pediatric scoliosis surgery, utilizing the Diagnosis Procedure Combination database, a national inpatient database in Japan.We retrospectively extracted data for patients aged less than 19 years who were admitted between 01 June 2010 and 31 March 2013 and underwent scoliosis surgery with fusion. The primary outcomes were in-hospital death and postoperative complications, including surgical site infection, ischemic heart disease, acute renal failure, pneumonia, stroke, disseminated intravascular coagulation, pulmonary embolism, and urinary tract infection.We identified 1,703 eligible patients (346 males and 1,357 females) with a mean age of 14.1 years. There were no deaths among the patients. At least one postoperative complication was found in 49 patients (2.9%). The most common complication was surgical site infection (1.4%). The multivariable logistic regression analysis showed that male sex (odds ratio, 2.22; 95% confidence interval, 1.28-3.70), comorbid diabetes (7.00; 1.56-31.51), and use of allogeneic blood transfusion (3.43; 1.86-6.41) were associated with the occurrence of postoperative complications. The present nationwide study elucidated the incidence and risk factors for in-hospital mortality and morbidity following surgery for pediatric scoliosis in an area other than North America. Diabetes was identified for the first time as a risk factor for postoperative complications in pediatric scoliosis surgery.

Instrumented cervical spinal fusions in children: indications and outcomes

PURPOSE

To report indications, outcomes and complications of instrumented cervical spinal fusion in a consecutive series of children at major university hospitals.

METHODS

A retrospective, single surgeon series identified 35 consecutive children with a mean follow-up (FU) of 2.5 years undergoing instrumented cervical spinal fusion between 2005 and 2015.

RESULTS

The main indications were skeletal dysplasia and trauma associated cervical instability. Surgical complications were observed in 12 (34%) patients with multiple complications in four (11%). Four (11%) children required at least one revision surgery, three for nonunion and one for graft dislodgement. All were fused at FU. Surgical complications were more common in children undergoing occipitocervical (OC) fusion than in those avoiding fusion of the OC junction (60% versus 24%) (p = 0.043). Complications were found significantly more in children operated on under the age of ten years than above (50% versus 18%) (p = 0.004). The risk of complications was not dependent on the indications for surgery (skeletal dysplasia versus trauma) (p = 0.177).

CONCLUSION

Skeletal dysplasia associated cervical instability and cervical spine injuries represented the most common indications for instrumented cervical spinal fusion in children. Complications were observed in one-third of these children and 11% required revision surgery for complications. OC spinal fusion and spinal fusion before the age of ten years are associated with higher risk of surgical complications and increased mortality than non-OC fusions and cervical spinal fusions at an older age. We urge surgeons to employ caution to the patient, timing and procedure selection when treating paediatric cervical spine.