Repeat surgical interventions following "definitive" instrumentation and fusion for idiopathic scoliosis

A 10-year perspective on the question of whether surgeries for adolescent idiopathic scoliosis are "one and done"?

PURPOSE

Posterior scoliosis fusion (PSF) for adolescent idiopathic scoliosis (AIS) is considered a highly successful surgery with excellent outcomes. However, especially as many patients "graduate" from their pediatric surgeons, there is the need to quantify the long-term outcomes of such surgeries.

METHODS

The 2010-2022 Pearldiver M161 dataset was queried for those who were 10 to 18 years old with AIS undergoing PSF with at least 10 years follow-up. Patient characteristics were abstracted. Reoperations were identified based on coding for any subsequent thoracic/lumbar surgery/revision. The 10-year reoperation rate and reasons for reoperation were determined, and multivariate regression was performed to determine risk factors.

RESULTS

In total, 3,373 AIS PSF patients were identified. Of the study cohort, 324 (9.6%) underwent reoperation within 10-years with an interquartile range for timing of surgery of 81-658 days, of which 29.6% were done for infection. Reoperations were done within the first three months for 152 (46.9% of reoperations), three months to 2 years for 97 (29.9%), and 2 years to 10 years for 74 (22.8%). Based on multivariate regression, need for reoperation was associated with male sex (OR: 1.70), asthma (OR: 1.36) and greater than thirteen segments of instrumentation (OR: 1.48) (p < 0.05 for each) but not age, other comorbidities, or insurance.

CONCLUSIONS

The current study of a large national AIS PSF population found 9.6% to undergo reoperation in the 10 years following their index operation. Although specifics about the curve pattern could not be determined, the reoperation incidence and correlation with specific risk factors are notable and important for patient counselling.

Costs of revision operations for distal junctional kyphosis following thoracic posterior spinal fusion for adolescent idiopathic scoliosis

PURPOSE

To assess direct costs and risks associated with revision operations for distal junctional kyphosis/failure (DJK) following thoracic posterior spinal instrumented fusions (TPSF) for adolescent idiopathic scoliosis (AIS).

METHODS

Children who underwent TPSF for AIS by a single surgeon (2014-2020) were reviewed. Inclusion criteria were minimum follow-up of 2 years, thoracolumbar posterior instrumented fusion with a lower instrumented vertebra (LIV) cranial to L2. Patients who developed DJK requiring revision operations were identified and compared with those who did not develop DJK.

RESULTS

Seventy-nine children were included for analysis. Of these, 6.3% developed DJK. Average time to revision was 20.8 ± 16.2 months. Comparing index operations, children who developed DJK had significantly greater BMIs, significantly lower thoracic kyphosis postoperatively, greater post-operative lumbar Cobb angles, and significantly more LIVs cranial to the sagittal stable vertebrae (SSV), despite having statistically similar pre-operative coronal and sagittal alignment parameters and operative details compared with non-DJK patients. Revision operations for DJK, when compared with index operations, involved significantly fewer levels, longer operative times, greater blood loss, and longer hospital lengths of stay. These factors resulted in significantly greater direct costs for revision operations for DJK ($76,883 v. $46,595; p < 0.01).

CONCLUSIONS

In this single-center experience, risk factors for development of DJK were greater BMI, lower post-operative thoracic kyphosis, and LIV cranial to SSV. As revision operations for DJK were significantly more costly than index operations, all efforts should be aimed at strategies to prevent DJK in the AIS population.

Repeat surgical interventions following "definitive" instrumentation and fusion for idiopathic scoliosis: a 30-year update

PURPOSE

Although spinal fusion (SF) is considered "definitive" treatment in juvenile/adolescent idiopathic scoliosis (JIS/AIS), complications requiring reoperation continue to occur. The purpose of this study was to characterize the evolving rates of reoperation following SF in JIS/AIS.

METHODS

Single-center retrospective review of patients who underwent SF for JIS/AIS as their index surgical treatment between 2013 and 2019. Patient data were collected to identify complications requiring reoperation and factors associated with reoperation. Complication rates from 2013 to 2019 were compared to patients from 1988 to 2012 at the same institution.

RESULTS

This study analyzed 934 patients (81.7% female, mean age at surgery 14.5 ± 2.1). Thirty-eight patients (4.1%) required a total of 47 reoperations, a > 50% decrease in overall complication rate from the 2008-2012 population (4.1% vs 9.6%, respectively, p < 0.001). The decrease stemmed mainly from decreases in rates of infection (1.1% vs 4.1%, p < 0.001) and symptomatic implants (0.4% vs 2.1%, p = 0.004). There were, however, non-significant increases in implant failures (0.6% vs 0.2%, p = 0.4367) and pseudoarthrosis (1.0% vs 0.4%, p = 0.5202). Both of these complications were associated with patients with a higher mean weight (implant failure: 70.4 kg ± 21.1 vs 56.1 kg ± 14.9, p = 0.002; pseudoarthrosis: 85.8 kg ± 27.9 vs 55.9 ± 14.5, p = 0.001).

CONCLUSIONS

Reoperation following SF for JIS/AIS has decreased over the past 7 years when compared to 25 years of historical controls. The changing landscape of reoperation demands further research into the risk factors for those reoperations that have become more common.

Efficiency of repeated corrective surgery in patients with spinal deformities: analysis of the immediate results of a monocenter cohort and a brief review of the literature

Objective. To analyze the results of repeated corrective surgery in patients with spinal deformities of various etiologies.

Material and Methods. The study group included 87 patients (mean age is 22.8 years, m : f = 10 : 77) who underwent repeated deformity correction using third-generation instrumentation (CDI and its analogues), and were selected from 144 patients previously operated on for spinal deformities of various etiologies using different types of spinal instrumentation. The magnitude of scoliotic deformity, thoracic kyphosis, lumbar lordosis, rotation of the apical vertebra, the volume of intraoperative blood loss, and the duration of the operation were assessed. All patients answered the questions of the SRS-24 questionnaire at the stages of treatment and postoperative follow-up, and were also examined by computer optical topography method.

Results. Out of 87 reoperated patients, 74 had idiopathic scoliosis. In 31 patients, the results were evaluated within a period of at least 2 years (average 61.8 months). As a result of the intervention, the primary curve was corrected by 29.1° (36.5 %). Loss of correction was 4.6° (p < 0.001), derotation of the apical vertebra – from 34.9° to 22.1° (p < 0.001) and loss of correction – 0.8°. The average blood loss varied from 810 to 1138 ml, and the operation time – from 187 to 289 min. Computer optical topography data convincingly confirmed the corrective effect achieved during the repeated intervention. According to the questionnaire (SRS-24), satisfaction with the results of the operation was quite high.

Conclusion. Repeated corrective interventions in patients with spinal deformities of various etiologies, even in long-term periods, can partially restore the lost primary correction and improve the quality of life of patients, which is confirmed by clinical and radiographic data, the results of computer optical topography and the SRS-24 questionnaire.

Comparison of Relative Value Units and 30-Day Outcomes Between Primary and Revision Pediatric Spinal Deformity Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to compare the relative value units (RVUs) and 30-day outcomes between primary and revision pediatric spinal deformity (PSD) surgery.

SUMMARY OF BACKGROUND DATA

PSD surgery is frequently complicated by the need for reoperation. However, there is limited literature on physician reimbursement rates and short-term outcomes following primary versus revision spinal deformity surgery in the pediatric population.

MATERIALS AND METHODS

This study utilizes data obtained from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Pediatric database. Patients between 10 and 18 years of age who underwent posterior spinal deformity surgery between 2012 and 2018 were included. Univariate and multivariate regression were used to assess the independent impact of revision surgery on RVUs and postoperative outcomes, including 30-day readmission, reoperation, morbidity, and complications.

RESULTS

The study cohort included a total of 15,055 patients, with 358 patients who underwent revision surgery. Patients in the revision group were more likely to be younger and male sex. Revision surgery more commonly required osteotomy (13.7% vs. 8.3%, P =0.002).Univariate analysis revealed higher total RVUs (71.09 vs. 60.51, P <0.001), RVUs per minute (0.27 vs. 0.23, P <0.001), readmission rate (6.7% vs. 4.0%, P =0.012), and reoperation rate (7.5% vs. 3.3%, P <0.001) for the revision surgery group. Morbidity rates were found to be statistically similar. In addition, deep surgical site infection, pulmonary embolism, and urinary tract infection were more common in the revision group. After controlling for baseline differences in multivariate regression, the differences in total RVUs, RVUs per minute, reoperation rate, and rate of pulmonary embolism between primary and revision surgery remained statistically significant.

CONCLUSIONS

Revision PSD surgery was found to be assigned appropriately higher mean total RVUs and RVUs per minute corresponding to the higher operative complexity compared with primary surgery. Revision surgery was also associated with poorer 30-day outcomes, including higher frequencies of reoperation and pulmonary embolism.

LEVEL OF EVIDENCE

Level III.

Indications and timing of revision spine surgery in adults after adolescent surgery for idiopathic scoliosis

STUDY DESIGN

Retrospective case series.

PURPOSE

To characterize the indications and timing of revision spine surgery in adulthood after adolescent surgery for idiopathic scoliosis. Previous studies have shown that revision usually occurs within 3 months or more than 5 years after the index operation. It is not clear what the indications for and timeline to revision surgery are in these patients during adulthood.

METHODS

421 patients with idiopathic scoliosis were seen as adults over a 15-year period. 81 patients who had scoliosis surgery prior to age 18 were identified. This cohort was studied for indications and time from index to revision operation. Their clinical presentation and a description of their revision operation was also documented.

RESULTS

Of the 81 patients, 18 (22.2%) had a revision surgery as an adult. Indications for revision in order of prevalence were implant malposition, subjacent segment degeneration and stenosis, pseudoarthrosis, delayed deep wound infection, spondylolisthesis, and symptomatic implants. Revisions were indicated generally within 15 years or more than 30 years after the initial operation.

CONCLUSIONS

The timeline for revision spine surgery in idiopathic scoliosis was bimodal, with revisions occurring within 15 years or over 30 years after the initial operation. Implant malposition and subjacent segment degeneration were the most prevalent indications for adulthood revision.

LEVEL OF EVIDENCE

Prognostic-IV.

A Two-Surgeon Approach Improves Performance for Young Surgeons in Adolescent Idiopathic Scoliosis

Adolescent idiopathic scoliosis (AIS) is a complex 3-dimensional deformity. Previous studies have suggested a learning curve in the successful execution of this technically demanding procedure. A 2-surgeon model may be helpful for less experienced surgeons by facilitating greater consistency in surgical metrics. The objective of this study was to show no significant difference in the parameters examined for surgeries done by inexperienced primary surgeons with a 2-surgeon model compared with those done by their more experienced cohorts. All surgeries with a primary diagnosis of AIS that were performed from January 2012 to December 2015 and had a minimum of 2-year follow-up were included for analysis. Three groups were created based on surgeon experience: inexperienced surgeons (IS) group, experienced surgeons (ES) group, and a third group where the primary surgeon was in the experienced group and the assistant surgeon was in the inexperienced group (EIS). Variables included for analysis were age, Lenke classification, number of levels fused, length of surgery, length of stay, percent curve correction, ratio of estimated blood loss to levels fused, surgical blood loss, and complications. There were no significant differences between the groups in terms of operative time, blood loss, number of levels fused, lower estimated blood loss ratio to the number of levels fused, or percent curve correction (P>.05). The IS group was found to have a significant shorter length of stay (P=.004). The 2-surgeon model is an effective tool for inexperienced surgeons to achieve consistent and reproducible operative performance that is comparable with their more experienced peers. [Orthopedics. 2021;44(3):e347-e352.].

Very long-term clinical and radiographic outcomes after posterior spinal fusion with pedicular screws for thoracic adolescent idiopathic scoliosis

PURPOSE

To report radiographic and functional outcomes, with an average follow-up of 20 years, of adolescents treated surgically for thoracic idiopathic scoliosis by hybrid construct using only pedicular screws for the distal fixation.

METHODS

We retrospectively reviewed 109 patients. Radiographic data were evaluated on fullspine radiographs (Cobb angle, pelvic incidence, sacral slope, pelvic tilt, thoracic kyphosis, lumbar lordosis). Clinical data were evaluated with ODI, SF-12, SRS-30 and Analog Pain Scale. Disc height and listhesis below the arthrodesis were measured.

RESULTS

We analyzed 90 women and 19 men with a mean age of 16.9 y.o. at surgery. Radiographic data were assessed for 46 patients after 17.4 years. Mean preoperative Cobb angle was 58°, mean correction 40.1% with 5.3° of loss at final FU. Lumbar lordosis and thoracic kyphosis increased significantly at last FU. Degenerative changes below the arthrodesis were reported in 5 cases. Clinical data were assessed for 42 patients after 19.9 years: SRS-30 3.8; ODI 12.3%; SF-12 PCS 48.6 and MCS 46. Low back pain was reported in 69% of cases with low intensity (3.1). The lowest instrumented vertebrae did not influence significantly the functional outcome.

CONCLUSIONS

The correction of thoracic AIS with lumbar or thoracolumbar pedicle screw instrumentation provides good radiological and clinical outcomes at very long term. The reduction in the coronal plane is stable; the HRQoL is quite as good as the general population. The degenerative evolution below remain relatively rare, therefore global sagittal balance is not modified.

Predicting the Failure Risk of Internal Fixation Devices in Chinese Patients Undergoing Spinal Internal Fixation Surgery: Development and Assessment of a New Predictive Nomogram

The current study is aimed at developing and validating a nomogram of the risk of failure of internal fixation devices in Chinese patients undergoing spinal internal fixation. We collected data from a total of 1139 patients admitted for spinal internal fixation surgery at the First Affiliated Hospital of Guangxi Medical University from May 2012 to February 2019. Of these, 1050 patients were included in the spinal internal fixation group and 89 patients in the spinal internal fixation device failure group. Patients were divided into training and validation tests. The risk assessment of the failure of the spinal internal fixation device used 14 characteristics. In the training test, the feature selection of the failure model of the spinal internal fixation device was optimized using the least absolute shrinkage and selection operator (LASSO) regression model. Based on the characteristics selected in the LASSO regression model, multivariate logistic regression analysis was used for constructing the model. Identification, calibration, and clinical usefulness of predictive models were assessed using C-index, calibration curve, and decision curve analysis. A validation test was used to validate the constructed model. In the training test, the risk prediction nomogram included gender, age, presence or absence of scoliosis, and unilateral or bilateral fixation. The model demonstrated moderate predictive power with a C-index of 0.722 (95% confidence interval: 0.644-0.800) and the area under the curve (AUC) of 0.722. Decision curve analysis depicted that the failure risk nomogram was clinically useful when the probability threshold for internal fixation device failure was 3%. The C-index of the validation test was 0.761. This novel nomogram of failure risk for spinal instrumentation includes gender, age, presence or absence of scoliosis, and unilateral or bilateral fixation. It can be used for evaluating the risk of instrumentation failure in patients undergoing spinal instrumentation surgery.

Comparing short-term AIS post-operative complications between ACS-NSQIP and a surgeon study group

STUDY DESIGN

Prospective cohort review.

OBJECTIVE

To compare two AIS databases to determine if a performance improvement-based surgeon group has different outcomes compared to a national database. The American College of Surgeon's National Quality Improvement Program (ACS-NSQIP) and a surgeon study group (SG) collect prospective data on AIS surgery outcomes. NSQIP offers open enrollment to all institutions, and SG membership is limited to 15 high-volume institutions, with a major initiative to improve surgeon performance. While both provide important outcome benchmarks, they may reflect outcomes that are not relatable nationwide.

METHODS

The ASC-NSQIP Pediatric Spine Fusion and SG database were queried for AIS 30- and 90-day complication data for 2014 and 2015. Prospective enrollment and a dedicated site coordinator with rigorous data quality assurance protocols existed for both registries. Outcomes were compared between groups with respect to superficial and deep surgical site infections (SSI), neurologic injury, readmission, and reoperation.

RESULTS

There were a total of 2927 AIS patients included in the ASC-NSQIP data and 721 in the SG database. Total complication rate was 9.4% NSQIP and 3.6% SG. At 90 days, there were fewer surgical site infections reported by SG than ASC-NSQIP (0.6% vs. 1.6%, p = 0.03). Similarly, there were less spinal cord injuries (0.8% vs 1.5%, p = 0.006), 30-day readmissions (0.8% vs. 2.6%, p = 0.002), and 30-day reoperations (0.6% vs. 1.7%, p = 0.02) in the SG cohort.

CONCLUSIONS

Comparison of these two data sets suggests a range of complications and readmission rates, with the SG demonstrating lower values. These results are likely multi-factorial with the performance improvement initiative of the SG playing a role. Understanding the rate and ultimate risk factors for readmission and complications from big data sources has the potential to further drive quality improvement.

LEVEL OF EVIDENCE

III.

Incidence and risk factors of reoperation in patients with adjacent segment disease: A meta-analysis

Study Design:

This was a systematic review of the literature and meta-analysis.

Objective:

The objective of this study was to evaluate the current literature regarding the risk factors contributing to reoperation due to adjacent segment disease (ASD).

Summary of Background Data:

ASD is a broad term referring to a variety of complications which might require reoperation. Revision spine surgery is known to be associated with poor clinical outcomes and high rate of complications. Unplanned reoperation has been suggested as a quality marker for the hospitals.

Materials and Methods:

An electronic search was conducted using PubMed. A total of 2467 articles were reviewed. Of these, 55 studies met our inclusion criteria and included an aggregate of 1940 patients. Data were collected pertaining to risk factors including age, sex, fusion length, lumbar lordosis, body mass index, pelvic incidence, sacral slope, pelvis tilt, initial pathology, type of fusion procedure, floating versus sacral or pelvic fusion, presence of preoperative facet or disc degeneration at the junctional segment, and sagittal orientation of the facets at the junctional segment. Analysis of the data was performed using Comprehensive Meta-Analysis software (Biostat, Inc.).

Results:

The overall pooled incidence rate of reoperation due to ASD from all included studies was 0.08 (confidence interval: 0.065–0.098). Meta-regression analysis demonstrated no significant interaction between age and reoperation rate (P = 0.48). A comparison of the event rates between males and females demonstrated no significant difference between male and female reoperation rates (P = 0.58). There was a significantly higher rate of ASD in patients with longer fusion constructs (P = 0.0001).

Conclusions:

We found that 8% of patients in our included studies required reoperation due to ASD. Our analysis also revealed that longer fusion constructs correlated with a higher rate of subsequent revision surgery. Therefore, the surgeon should limit the number of fusion levels if possible to reduce the risk of future reoperation due to ASD.

Level of evidence:

IV

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.

Incidence of complete spinal instrumentation removal following surgery for spinal deformity: a 22-year single institution study

The aim of this study was to define the incidence of complete implant removal following surgical correction of spinal deformity in pediatric patients over a 22-year period and identify possible risk factors. A retrospective review of our Pediatric Orthopedic Spine Database between 1992 and 2016 was performed. We included patients undergoing complete implant removal following scoliosis correction surgery with a minimum of 2-year follow-up. Medical charts were reviewed to determine initial patient diagnosis and the indication for implant removal. Statistical analysis was carried out to determine the associations between sex and factors such as primary diagnosis and indication for removal. A review of 1117 procedures in 1114 patients identified complete instrument removal in 52 (4.7%) patients (34 females and 18 males). Mean time to removal following surgery was 2.3 years (range: 0-5.9 years). Removal occurred in 24 of 548 (4.4%) patients with adolescent idiopathic scoliosis, four of 117 (3.4%) patients with juvenile idiopathic scoliosis, 11 of 287 (3.8%) patients with neuromuscular scoliosis, and three of 79 (3.8%) patients with syndromic scoliosis. Infection was the most common indication for complete implant removal [24 (46%) patients], followed by persistent pain [8 (15%) patients], and metal intolerance [8 (15%) patients]. There were two cases of early infection (<1 year following surgery) and 22 late infections (≥1 year following surgery). The overall 22-year incidence of complete implant removal following spinal correction surgery for scoliosis was 4.7%. Infection continues to be the most common indication, followed by pain and metal intolerance.

Secondary Surgery Rates After Primary Fusion for Adolescent Idiopathic Scoliosis

Instrumented spinal fusion is the gold standard treatment for surgical magnitude adolescent idiopathic scoliosis (AIS), with the goal being stable fusion without the need for additional procedures. The purpose of this study was to define the surgical return rates of AIS at a single center with respect to various instrumentation constructs used during initial spinal fusion. A retrospective chart review was performed of all patients with AIS who underwent instrumented fusion with a minimum of 2-year follow-up. Demographic information, implant type, and surgical approach for the primary surgery and all subsequent secondary operations were recorded. Four hundred eleven patients who underwent instrumented fusion for AIS during the study period met inclusion criteria. Sixty-six secondary operations were performed in 50 patients (12.2%). Symptomatic hardware, pseudarthrosis, and infection were the most common indications for secondary surgery. Posterior pedicle screw constructs had a lower secondary surgery rate (5.8%) compared with hybrid and combined fusions (P<.05). The all hook, hybrid, anterior only, and combined fusions had secondary surgery rates of 13.0%, 18.5%, 10.0%, and 20.8%, respectively, which were not statistically different. When specifically comparing pedicle screw with hook constructs, there was a statistically lower pseudarthrosis rate (P=.03) favoring pedicle screw instrumentation. Patients undergoing instrumented fusion for AIS are at some risk for subsequent surgery. To lessen that risk, pedicle screw constructs should be considered, as they have shown an overall lower secondary surgery rate and in particular a lower rate of pseudarthrosis. [Orthopedics. 2019; 42(4):235-239.].

A Technical Note on Making Patient-Specific Pedicle Screw Templates for Revision Pediatric Kyphoscoliosis Surgery with Sublaminar Wires In Situ

Introduction:

Revision deformity correction surgery of a pediatric spine, especially with sublaminar Soacing between wires in situ, is a daunting task for patient as well as treating physician. Obscured native anatomy in the presence of sublaminar wires poses a staunch intraoperative challenge for a surgeon for safe placement of pedicle screws so as to avoid neurological and vascular injury. In revision surgeries with previous implants, it’ is challenging, especially due to metal artifacts in imaging, bone loss due to previous surgery. In this note, we describe the technique of making making three-dimensional (3D)-printed patient-specific templates for safe placement of pedicle screws in pediatric patients undergoing revision kyphoscoliosis surgery with sublaminar wires in situ.

Case Report:

A 12-year-old female presented to the clinic with a history of early-onset scoliosis, for which she underwent deformity correction surgery with spinal rectangle loop and sublaminar wires 4 years ago. At presentation, she had decompensated with increase in deformity and failed implant. She underwent revision deformity correction surgery with pedicle screws. 3D-printed patient-specific pedicle screw templates were useful in this patient for appropriate pedicle screw placement, as patient had obscured native anatomy due to fusion mass and in situ sublaminar wires.

Conclusion:

3D-printed patient-specific pedicle screw templates are very useful in revision pediatric deformity correction surgeries, especially when the obscured native bony anatomy makes free-hand insertion of pedicle screw unsafe.

Repeat Surgical Interventions Following "Definitive" Instrumentation and Fusion for Idiopathic Scoliosis: 25-Year Update

STUDY DESIGN

Single-institution, retrospective review of prospectively collected data on pediatric patients with adolescent idiopathic scoliosis (AIS) undergoing spinal fusion with a minimum two-year follow-up.

OBJECTIVE

To determine the rate of reoperation in AIS patients undergoing spine fusion from 2008 to 2012.

SUMMARY OF BACKGROUND DATA

Recent trends in the surgical treatment of AIS have included increased use of all-pedicle screw constructs, smaller implants, more posterior-only approaches, and improved correction techniques.

METHODS

A retrospective review of 467 patients undergoing spinal fusion from 2008 to 2012 was performed. Demographic, clinical, radiographic, and surgical data were collected prospectively on all patients for the index procedure and any reoperations. Data were compared to previously published cohorts of patients from the authors' institution who underwent spinal fusion for AIS between 1988 and 2007.

RESULTS

The rate of reoperation in this five-year cohort of patients was 9.9%. The most common indications for reoperation were infection (4.5%: 2.4% delayed infections and 2.1% acute infections), symptomatic implants (2.1%), and misplaced pedicle screws (1.7%). When compared to the 2003-2007 cohort, the rate of reoperation for acute infection and malpositioned pedicle screws increased significantly (p = .01 and p = .04), whereas the rate of reoperation for curve progression decreased (p = .01). Reoperations for acute infections and malpositioned pedicle screws also increased significantly (p = .047 and p = .042) compared with the 1988-2002 cohort, whereas the rate of reoperation for pseudarthrosis decreased (p = .002).

CONCLUSION

Reoperation rates for AIS have not improved with more sophisticated implants and techniques, predominantly because of increased acute infections and malpositioned pedicle screws despite decreasing pseudarthrosis rates and curve progression.

LEVEL OF EVIDENCE

Level II.

Preventing Distal Junctional Kyphosis by Applying the Stable Sagittal Vertebra Concept to Selective Thoracic Fusion in Adolescent Idiopathic Scoliosis

STUDY DESIGN

Multicenter retrospective review.

OBJECTIVE

To assess the effectiveness of using the stable sagittal vertebra (SSV) for selecting the lowest instrumented vertebrae (LIV) to prevent distal junctional kyphosis (DJK) in selective thoracic fusions.

SUMMARY OF BACKGROUND DATA

Cho et al. reported that including the SSV in a fusion decreased the rate of DJK in thoracic hyperkyphosis.

METHODS

A retrospective review was performed of patients from two pediatric hospitals with adolescent idiopathic scoliosis who underwent selective posterior thoracic fusion with the LIV at L2 or above from 2000 to 2012. Patients with less than 2 years' follow-up were excluded. The primary outcome measure was DJK, defined radiographically as ≥10° between the superior end plate of the LIV and the inferior end plate of the vertebra below on a standing lateral radiograph. We investigated the SSV, which was defined as the vertebral level at which 50% of the vertebral body was in front of the posterior sacral vertical line (PSVL) on a standing lateral radiograph. This particular definition was referred to as SSV.

RESULTS

A total of 113 patients met the inclusion criteria. Mean age was 14.4 years. Mean Cobb angle was 58°. The overall rate of DJK was 7% (8/113). When the LIV was superior to SSV, the rate of DJK was 17% (8/46) versus 0% (0/67) when the LIV was at or inferior to SSV (p=.01). The rates of DJK for patients with the LIV one, two, and three levels above SSV were 17% (4/24), 7% (1/14), and 43% (3/7), respectively. There was no significant association between preoperative or postoperative maximum kyphosis, thoracic kyphosis, thoracolumbar kyphosis, pelvic incidence, sagittal balance or coronal balance, and development of DJK.

CONCLUSION

Although LIV selection is complex, choosing the LIV at or below the SSV is a simple rule that minimizes the risk of DJK.

LEVEL OF EVIDENCE

Level IV.

SRS-22r Scores in Nonoperated Adolescent Idiopathic Scoliosis Patients With Curves Greater Than Forty Degrees

STUDY DESIGN

Case control comparative series.

OBJECTIVE

Describe surgical range adolescent idiopathic scoliosis (AIS) patients electing to forgo surgery and compare health-related quality-of-life outcomes to a similar cohort of operated AIS patients by the same single surgeon.

SUMMARY OF BACKGROUND DATA

No data have been published either documenting SRS-22r scores of nonoperated patients with curves ≥40° or comparing these scores to a demographically similar operated cohort.

METHODS

Individuals with curves ≥40°, age ≥18 years, and electing to forgo surgery were identified. All patients completed an SRS-22r questionnaire. This nonoperated cohort's SRS-22r scores were compared to those of a large demographically similar cohort operated by the same surgeon. Group differences between the SRS-22r scores were evaluated by comparing these to published Minimal Clinically Important Differences (MCID) for the SRS-22r.

RESULTS

One hundred ninety subjects with nonoperated curves were compared to 166 individuals who underwent surgery. The nonoperated cohort averaged 23.5 years of age, averaged 7.7 years since curve reached 40°, and had an average 50° Cobb angle at last follow-up. No statistical significant differences were found between the groups on the Pain, Function, or Mental Health domains of the SRS-22r. Statistically significant differences in favor of the operative cohort were found for self-image, satisfaction, and total score. The observed group differences did not meet the established thresholds for minimal clinically important differences in any of the domain scores, the average total score, or raw scores.

CONCLUSION

There are no meaningful clinically significant differences in SRS-22r scores at average 8-year follow-up between AIS patients with curves ≥40° treated with or without surgery. These data in conjunction with an absence of long-term evidence of serious medical consequences with nonsurgical management of curves ≥40° should encourage surgeons to reevaluate the benefits of routine surgical care.

LEVEL OF EVIDENCE

3.

5-Year Reoperation Risk and Causes for Revision After Idiopathic Scoliosis Surgery

STUDY DESIGN

An actuarial "survivorship" analysis.

OBJECTIVE

The aim of this study was to define the incidence and cause of surgical revision 5 years after scoliosis surgery.

SUMMARY OF BACKGROUND DATA

Data on contemporary revision surgery rates after idiopathic scoliosis surgery beyond the 2 years postoperatively in the adolescent and young adult population are limited.

METHODS

Patients enrolled in a prospective, multicenter, idiopathic scoliosis surgical registry from 1995 to 2009 were reviewed. Any spine reoperation was defined as a "terminal event." An actuarial survivorship analysis that adjusts for patients lost to follow-up was performed to determine cumulative survival. Time intervals were defined as 0 to <3 months, 3 months to <1 year, 1 to <2 years, 2 to <5 years, and 5 to 10 years. Registry data and radiographs were reviewed and five categories for reoperation assigned: 1) implant failure and/or pseudarthrosis, 2) implant misplacement and/or prominence, 3) wound complication and/or infection, 4) residual deformity and/or progression, and 5) other.

RESULTS

One thousand four hundred thirty-five patients from 12 sites were included. The majority were female (80%), with major thoracic curves (76% Lenke 1-4), and average age of 15 ± 2 years (10-22) at surgery. Most had posterior spinal instrumentation and fusion (81%). At this time, 75 (5.2%) patients required reoperation. Twenty-two occurred within 3 months postop, 10 more before 1 year, 12 more before 2 years, another 20 by 5 years, and 10 more after 5 years. This corresponded to an actuarial cumulative survival of 98.3% at 3 months, 97.5% at 1 year, 96.6% at 2 years, 93.9% at 5 years, and 89.8% at the final interval (5-10 yrs).

CONCLUSION

Revisions for scoliosis continue to occur well after 2 years with a 5-year survivorship of 93.9%. Reasons for reoperation are not uniformly distributed over time, with implant-related issues and infection the leading cause for early revision, while late infection was the most common cause after 2 years. Long-term follow-up of these postoperative patients remains important.

LEVEL OF EVIDENCE

3.

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

STUDY DESIGN

Retrospective cohort study of a nationwide database.

OBJECTIVE

To compare in-hospital outcomes for pediatric patients who underwent primary versus revision spinal fusion.

SUMMARY OF BACKGROUND DATA

There is limited data on outcomes after primary versus revision spinal fusion in children.

METHODS

Data from the Nationwide Inpatient Sample from 2002 to 2011 were analyzed. Pediatric patients (age <18 yr) who underwent ≥3 level spinal fusion were identified. Demographics, in-hospital complications, length of stay, and hospital charges were compared between primary and revision (refusion) procedures. All analyses were performed after application of discharge weights.

RESULTS

Data from 72,483 primary fusion and 2042 revision fusion procedures (2.7%) were analyzed. Average length of stay was 7.9 days for the revision group and 6.6 for the primary group (P = 0.022). Average total charges were $135,644 and $142,029 for the revision and primary fusion groups, respectively (P = 0.252). The percentage of patients who developed at least one in-hospital complication was 16.7% in the revision group and 8.6% in the primary fusion group (P < 0.001). Specific complications that were more common in the revision group were reintubation (4.3% vs. 2.3%, P = 0.008), hemorrhage/hematoma (5.0% vs. 2.5%, P = 0.001), wound complications (4.0% vs. 1.1%, P < 0.001), accidental vessel/nerve puncture (2.6% vs. 0.8%, P < 0.001), implant-related complications (5.3% vs. 0.4%, P < 0.001), and incidental durotomy (2.1% vs. 0.3%, P < 0.001). On multivariate analysis, revision procedures (odds ratio [OR] 2.64; 95% confidence interval [CI] 1.93-3.59; P < 0.001), male sex (OR 1.73; 95% CI 1.52-1.98; P < 0.001), and fusion of eight or more spinal levels (OR 1.27; 95% CI 1.09-1.47; P = 0.001) were risk factors for complication development.

CONCLUSION

In the present study, pediatric patients who underwent spinal refusion had significantly higher complication rates compared to patients who underwent primary fusion, consistent with previous investigations. Male patients and patients who underwent fusion of eight or more spinal levels also had higher complication rates.

LEVEL OF EVIDENCE

3.

Associations Between Body Mass and Revision Surgical Outcomes in Adult Scoliosis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine whether an association exists between high body mass index (BMI>25 kg/m) and surgical outcomes in revision adult scoliosis patients.

SUMMARY OF BACKGROUND DATA

Obesity is thought to be associated with increased surgical complications and inferior clinical outcomes in adults. There are no studies analyzing the effect of obesity on surgical outcomes in revision patients for adult scoliosis.

METHODS

Forty-five consecutive revision adult scoliosis patients (35 women and 10 men; mean age, 62.7±9.3 y) with a minimum follow-up of 2 years were included in this study. Patients were divided into 2 groups according to BMI: overweight (BMI≥25 kg/m, n=27) and nonoverweight (<25 kg/m, n=18). Radiographic measures, Oswestry Disability Index (ODI), Visual Analog Scale (VAS), as well as comorbidities and complications were reviewed and compared at preoperative and 2-year follow-up.

RESULTS

No significant differences in surgical methods, complication rates, or radiographic measures were found between the 2 groups except for the greater preoperative and final follow-up thoracic kyphosis in the overweight group (P<0.05). A higher comorbidity rate of circulatory disorders (33.3% vs. 0%, P=0.018) and diabetes (25.9% vs. 0%, P=0.053) was observed in the overweight group, as well as a higher preoperative VAS score (7.1±1.7 vs. 5.2±2.9, P=0.031). At 2-year follow-up, VAS and ODI improvements for both groups showed significant and similar improvement from preoperative (P<0.01).

CONCLUSIONS

Overweight revision adult scoliosis patients had higher thoracic kyphosis and more significant preoperative pain compared with normal-weight individuals. Overweight patients also had significantly higher rates of medical comorbidities. However, BMI did not affect the functional outcome of surgical correction or perioperative complication rates. Overweight patients benefited from surgery just as much as nonoverweight patients at 2-year follow-up.

Risk of revision surgery for adult idiopathic scoliosis: a survival analysis of 517 cases over 25 years

PURPOSE

Little is known about the long-term status of patients operated for spine deformities. The aim of this study was to determine the survival of primary fusion in adult idiopathic scoliosis and identify the risk factors of revision surgery.

METHODS

Adult patients who underwent primary fusion for idiopathic scoliosis between 1983 and 2011 were included in a continuous monocentric retrospective series. Any additional surgery was registered for survival analysis. Survival and follow-up were estimated by the Kaplan-Meier method and an analysis was performed to identify the risk factors of revision surgery.

RESULTS

This series included 447 women (86.5 %) and 70 men (13.5 %) reviewed after a mean follow-up of 7 years (range 0-26.4). Mean age was 44.4 years. Fusion was performed on a median 11 levels (range 3-15); revision rate was 13 % (CI 10-17), 18 % (CI 14-23) and 20 % (CI 16-26) at 5, 10 and 15 years, respectively. Revision surgery was associated with age, anterior release, length of fusion, the inferior limit of fusion, post-operative sagittal balance and junctional kyphosis. The length of fusion (HR 1.13 per vertebrae fused, p = 0.007) and the lower limit of fusion (HR 5.9, p < 0.001) remained independent predictors of revision surgery on multivariate analysis.

CONCLUSION

This series evaluated the risk of revision surgery following spinal fusion for idiopathic scoliosis. Our results show that the risk seemed to increase linearly with a rate of nearly 20 % after 10 years. The length and lower limit of fusion are the main risk factors for revision surgery. Level IV (e.g. case series).

Infection after anterior spinal fusion for idiopathic scoliosis using the Cotrel-Dubousset-Hopf system: A clinical case series of three patients

BACKGROUND

Three patients with late-onset infection after multilevel instrumented anterior spinal fusion for idiopathic scoliosis, using the Cotrel-Dubousset-Hopf (CDH) system, are presented. The CDH-system is an anterior instrumentation with high biomechanical stability and rigidity, ensuring a stable primary fixation. Unlike after posterior spinal fusion, infection after anterior spinal fusion (ASF) for idiopathic scoliosis has rarely been reported.

METHODS

The files of three patients who developed an infection after ASF for scoliosis using the CDH-system, were reviewed. The clinical presentation and diagnostic and therapeutic options are discussed.

RESULTS

All three patients had a late-onset infection of the CDH-system, which was difficult to diagnose because of nonspecific symptoms. Radiographs and technetium bone scan appeared to be of low value. When an abscess was present, this could accurately be diagnosed with MRI or CT imaging. Operative treatment with implant removal and antibiotic therapy was successful in all cases.

CONCLUSION

Late onset infections after ASF using the CDH-system presented with few and nonspecific symptoms. The clinical presentation was mainly characterized by vague abdominal- or back-pain after an interval of normal postoperative recovery, moderately raised infection parameters and inconclusive findings with imaging modalities. As treatment, implant removal, debridement and parenteral antibiotics are recommended. It should be noted though that implant removal poses serious risks for vascular and visceral structures.

Impact of Increasing Age on Outcomes of Spinal Fusion in Adult Idiopathic Scoliosis

OBJECTIVE

To investigate the role of advancing age on postoperative complications and revision surgery after fusion for scoliosis.

METHODS

A retrospective, cohort study was performed using the Thomson Reuters MarketScan database, examining patients with adult scoliosis who underwent spinal fusion from 2000 to 2009. Primary outcomes included infection, hemorrhage and pulmonary embolism (PE) within 90 days of surgery, and refusion. The effect of increasing age was estimated using the odds ratio (OR) of complications in a multivariate logistic regression analysis, and a Cox proportional hazard model estimated the hazard ratio of refusion.

RESULTS

A total of 8432 patients were included in this study. Overall, the average age was 53.3 years, with 26.90% males and 39% with a Charlson Comorbidity Score of ≥ 1. Most patients had commercial insurance (66.81%), with 26.03% and 7.16% covered by Medicare and Medicaid, respectively. Increasing age (per 5-year increment) was a significant predictor of hemorrhagic complication (OR, 1.06; confidence interval [CI], 1.01-1.11; P = 0.0196), PE (OR, 1.09; CI, 1.03-1.16; P = 0.0031), infection (OR, 1.04; CI, 1.01-1.07; P = 0.0053), and refusion (hazard ratio, 1.07; CI, 1.02-1.13; P = 0.0103).

CONCLUSIONS

In this study, age was associated with increased risk of hemorrhage, PE, infection, and refusion. With the aging population, the role of patient age on postoperative healing and outcomes deserves deeper investigation after repair of adult idiopathic scoliosis.

Unplanned reoperation after lumbopelvic fixation with S-2 alar-iliac screws or iliac bolts

OBJECT

S-2 alar-iliac (S2AI) screws are an attractive alternative to conventional fixation with iliac bolts because they are lower profile, require less muscle dissection, and have greater pullout strength. Few studies, however, compare outcomes between these techniques.

METHODS

The authors conducted a retrospective cohort study of consecutive adult patients at a single institution from December 2009 to March 2012 who underwent lumbopelvic fixation using S2AI screws or iliac bolts. Medical records were reviewed for patients with clinical failure, defined as an unplanned reoperation because of instrumentation failure and/or wound-related complications. Univariate, multivariate, and survival analyses were used to compare patients who required reoperation with those who did not. Method of pelvic fixation was the main predictor variable of interest, and the authors adjusted for potential confounding risk factors.

RESULTS

Of the 60 patients included, 23 received S2AI screws. Seventeen patients (28%) underwent an osteotomy. The mean follow-up was 22 months. A Kaplan-Meier survival model was used to evaluate the time to reoperation from the initial placement of lumbopelvic instrumentation. The failure-free rate was 96.6% at 6 months, 87.0% at 1 year, and 73.5% at 2 years. Reoperation was more common in patients with iliac bolts than in those with S2AI screws (13 vs 2; p = 0.031). Univariate analysis identified potential risk factors for unplanned reoperation, including use of iliac bolts (p = 0.031), absence of L5–S1 interbody graft (p = 0.048), previous lumbar fusion (p = 0.034), and pathology other than degenerative disease or scoliosis (p = 0.034). After adjusting for other risk factors, multivariate analysis revealed that the use of S2AI screws (OR 8.1 [1.5–73.5]; p = 0.030) was the only independent predictor for preventing unplanned reoperation.

CONCLUSIONS

Both S2AI screws and iliac bolts were effective at improving fusion rates at the lumbosacral junction. The use of S2AI screws, however, was independently associated with fewer unplanned reoperations for wound-related complications and instrumentation failures than the use of iliac bolts.

Unplanned Hospital Readmissions and Reoperations After Pediatric Spinal Fusion Surgery

STUDY DESIGN

Retrospective review.

OBJECTIVE

To investigate the rates and reasons for unplanned readmissions and reoperation after pediatric spinal fusion surgery at our institution and to identify risk factors by analyzing patient and surgical characteristics. Unplanned readmission and reoperation were defined as unplanned events within 90 days of the index surgery.

SUMMARY OF BACKGROUND DATA

The rate of unplanned readmission and reoperation after pediatric spinal fusion surgery is not well established.

METHODS

Clinical records were reviewed for all children who underwent spinal fusion surgical procedures for spinal deformity correction performed by 1 surgeon from 2000 through 2013 at our institution. Inclusion criteria were age of 10 to 18 years at surgery, fusion spanning more than 5 vertebral levels, and 3 months of clinical or radiographical follow-up (1002 patients met these criteria). Univariate and multivariate logistic regression models were created. Statistical significance was set at a P value of less than 0.05 for all analyses.

RESULTS

The overall 90-day unplanned readmission and reoperation rates were 8.0% and 3.8%, respectively. The most common causes of readmission were wound dehiscence (1.8%), deep wound infection (1.5%), pulmonary complications (1%), and superficial wound infection (0.9%). Univariate analysis showed that readmission was significantly associated with a higher number of levels fused, greater estimated blood loss, longer length of stay, and certain diagnoses; reoperation was significantly associated with a higher number of levels fused and certain diagnoses. On multivariate analysis, only patient diagnosis was found to be significantly associated with readmission and reoperation; patients with congenital scoliosis, genetic or syndromic scoliosis, cerebral palsy, and other neuromuscular disorders had significantly higher rates.

CONCLUSION

Unplanned readmission rate after pediatric spinal fusion surgery was 8%, most commonly for wound dehiscence and deep and superficial infections. Increased intraoperative blood loss, higher number of levels fused, and certain diagnoses are risk factors for unplanned readmission.

LEVEL OF EVIDENCE

4.

Revision surgery for pediatric spine deformity: corrective osteotomies

BACKGROUND

Revision spinal deformity surgery is a considerable undertaking and should never be taken lightly. The complication rates are typically higher than index surgery and technical difficulties are of greater magnitude.

METHODS

A review of the literature on revision surgery on pediatric spine deformities is provided with technical details of vertebral column resection.

CONCLUSIONS

Careful planning and preparation as well as previous experience with such deformities are of utmost importance to achieve satisfactory results.

Risk factors for surgical site infections after pediatric spine operations

STUDY DESIGN

Matched case-control study.

OBJECTIVE

To identify modifiable risk factors for surgical site infections (SSIs) after pediatric spinal fusion.

SUMMARY OF BACKGROUND DATA

The number of SSIs after pediatric spinal fusions increased.

METHODS

Between July 2001 and July 2010, 22 of 598 pediatric patients who underwent spinal fusion at a university hospital acquired SSIs. Each patient with an SSI was matched with 2 controls by procedure date. Bivariable and multivariable analyses were used to identify risk factors for SSIs and outcomes of SSIs.

RESULTS

Gram-negative organisms caused more than 50% of the SSIs. By multivariable analysis, neuromuscular scoliosis (odds ratio [OR] = 20.8; 95% confidence interval [CI], 3.1-889.5; P < 0.0001) and weight-for-age at the 95th percentile or higher (OR = 8.6; 95% CI, 1.2-124.9; P = 0.02) were preoperative factors associated with SSIs. Blood loss (OR = 1.0; 95% CI, 1.0-1.0; P = 0.039) and allografts and allografts in combination with other grafts were operative risk factors for SSIs. The final overall risk model for SSIs was weight-for-age at the 95th percentile or higher (OR = 4.0; 95% CI, 1.4-∞; P = 0.037), American Society of Anesthesiologists score 3 or more (OR = 3.8; 95% CI, 1.6-∞; P = 0.01), and prolonged operation duration (OR = 1.0/min increase; 95% CI, 1.0-1.0; P = 0.004). SSIs were associated with 2.8 days of additional postoperative length of stay (P = 0.02). Neuromuscular scoliosis was the only factor significantly associated with hospital readmission (OR = 23.6; 95% CI, 3.8-147.3; P = 0.0007).

CONCLUSION

Our results suggest that pediatric patients undergoing spinal fusion might benefit from antimicrobial prophylaxis that covers gram-negative organisms. Surgical duration, graft implantation, and blood loss are potentially modifiable operative risk factors. Neuromuscular scoliosis, high weight-for-age, and American Society of Anesthesiologists scores 3 or more may help surgical teams identify patients at high risk for SSI.

Idiopathic scoliosis: the tethered spine II: post-surgical pain

The treatment of severe chronic pain in young people following surgery for the correction of curvatures of idiopathic scoliosis (IS) is presented through two case histories. Effective treatment involved release of myofascial trigger points (TrPs) known to refer pain into the spine, and treatment of related fascia and joint dysfunction. The TrPs found to be contributing to spinal area pain were located in muscles at some distance from the spine rather than in the paraspinal muscles. Referred pain from these TrPs apparently accounted for pain throughout the base of the neck and thoracolumbar spine. Exploratory surgery was considered for one patient to address pain following rod placement but the second surgery became unnecessary when the pain was controlled with treatment of the myofascial pain and joint dysfunction. The other individual had both scoliosis and hyperkyphosis, had undergone primary scoliosis surgery, and subsequently underwent a second surgery to remove hardware in an attempt to address her persistent pain following the initial surgery (and because of dislodged screws). The second surgery did not, however, reduce her pain. In both cases these individuals, with severe chronic pain following scoliosis corrective surgery, experienced a marked decrease of pain after myofascial treatment. As will be discussed below, despite the fact that a significant minority of individuals who have scoliosis corrective surgery are thought to require a second surgery, and despite the fact that pain is the most common reason leading to such revision surgery, myofascial pain syndrome (MPS) had apparently not previously been considered as a possible factor in their pain.

Outcomes following removal of instrumentation after posterior spinal fusion

BACKGROUND

Although there is good evidence to support the removal of instrumentation for infection following posterior spine fusion, there are few studies that report outcomes following removal for late operative site pain. The purpose of this study was 3-fold: (1) to determine whether removal of instrumentation following posterior spinal fusion resolves preoperative pain, (2) to determine whether indolent infection not detected before removal of instrumentation is related to late operative site pain, and (3) to determine whether curve progression differs when spinal hardware is removed for infection versus late operative site pain.

METHODS

A retrospective study of consecutive patients aged 10 to 21 years, who underwent removal of instrumentation after posterior spinal fusion over a 10-year-period was conducted. Patient demographics, preoperative and postoperative imaging results, laboratory studies, and operative findings were reviewed. All patients had a minimum 2-year follow-up. Statistical analysis was performed using 2-sample t test, bivariate analysis, and multivariate logistic regression models.

RESULTS

Seventy-five patients were included. Indications for removal of spinal instrumentation were pain (57%), infection (28%), hardware failure (8%), and prominent hardware (7%). The mean time from index procedure to hardware removal was 2.8 years. The average loss of curve correction following complete hardware removal was 23.1 degrees. Patients who underwent removal of hardware because of infection had bigger changes in their curves than those without infection (mean, 33.8 degrees vs. 18.8 degrees). Of the 43 patients with pain, only 40% reported relief of their symptoms following removal of hardware. Sixteen of the 43 patients were found to have indolent infection confirmed by positive intraoperative culture results.

CONCLUSIONS

Patients should be cautioned that hardware removal after posterior spinal fusion may not provide complete pain relief. Furthermore, there is risk for curve progression following removal of instrumentation, particularly in the setting of infection. Back pain may be an indicator of infection, and intraoperative cultures should be taken at the time of implant removal.

LEVEL OF EVIDENCE

Level IV; retrospective case series.

Survivorship analysis after primary fusion for adult scoliosis. Prognostic factors for reoperation

BACKGROUND CONTEXT

Adult scoliosis surgery is a challenging procedure with high rate of complications and reoperations. Reoperation rates vary widely. Long-term survival for this surgery still remains unknown, and the prognostic factors for reoperation are not well defined.

PURPOSE

To assess adult scoliosis surgery survival (without the need of reoperation) after primary fusion in adults with mainly frontal deformity and to define prognostic factors for reoperation.

STUDY DESIGN

Survival analysis of a cohort of consecutive adult patients, primarily operated on scoliosis using segmental instrumentation (retrospective cohort study).

PATIENT SAMPLE

Fifty-nine patients older than 21 years at primary surgery (median age, 42 years), who presented idiopathic or degenerative curves with frontal Cobb >40° (median preoperative frontal Cobb 59°), more than four-level fusion, and a 2-year minimum postoperative follow-up (median, 8.5 years; 41% patients had a longer than 10-year follow-up).

OUTCOME MEASURES

Clinical and preoperative radiographic parameters were analyzed preoperatively and evaluated as prognostic factors for reoperation.

METHODS

Survival was estimated using Kaplan-Meier method. Prognostic factors (clinical and radiographic) for reoperation were evaluated. Logistic regression using backward elimination was used for multivariate analysis.

RESULTS

Survival was 89.8% at 1 year, 79.4% at 2 years, 73.4% at 3 years, 64% at 5 years, and 60.9% at 10 years. Overall, 21 patients (35.6%) underwent revision surgery. The most common reasons for reoperation were painful/prominent implants, adjacent-segment degeneration, and infection. American Society of Anesthesiologists Type II patients and double surgical approach were associated with a higher revision rate. Preoperative thoracic kyphosis was significantly higher in reoperated patients.

CONCLUSIONS

The 10-year survival rate of primary scoliosis surgery in adult patients is 61%. Risk factors identified for reoperation included patients with higher morbidity, double surgical approach, and preoperative thoracic hyperkyphosis.

Unplanned reoperation within 30 days of fusion surgery for spinal deformity

No recent studies have analyzed the rates of or reasons for unanticipated revision surgery within 30 days of primary surgery in spinal deformity patients. Our aim was to examine the incidence, characteristics, reasons, and risk factors for unplanned revision surgery in spinal deformity patients treated at one institution. All patients with a diagnosis of spinal deformity presenting for primary instrumented spinal fusion at a single institution from 1998 to 2012 were reviewed. All unplanned reoperations performed within 30 days after primary surgery were analyzed in terms of demographics, surgical data, and complications. Statistical analyses were performed to obtain correlations and risk factors for anticipated revision. Of 2758 patients [aged 16.07 years (range, 2–71), 69.8% female] who underwent spinal fusion surgery, 59 (2.1%) required reoperation within 30 days after primary surgery. The length of follow up for each patient was more than 30 days. Of those that required reoperation, 87.0% had posterior surgery only, 5.7% had anterior surgery, and 7.3% underwent an anteroposterior approach. The reasons for reoperation included implant failure (n = 20), wound infection (n = 12), neurologic deficit (n = 9), pulmonary complications (n = 17), and coronal plane imbalance (n = 1). The risk factors for reoperation were age, diagnosis, and surgical procedure with osteotomy.

Unplanned return to the operating room in patients with adolescent idiopathic scoliosis: are we doing better with pedicle screws?

STUDY DESIGN

Prospective, longitudinal cohort.

OBJECTIVE

To evaluate the incidence, timing, and risk factors for reoperation in patients with adolescent idiopathic scoliosis (AIS) treated with pedicle screws (PSs) compared with hybrid (Hb) constructs.

SUMMARY OF BACKGROUND DATA

Rates of return to the operating room (OR) after definitive fusion for AIS vary, with a paucity of data on PS constructs.

METHODS

A prospective multicenter database was retrospectively queried to identify consecutive patients with AIS who underwent posterior spinal fusion with either PS or Hb constructs with a minimum 2-year follow-up. All reoperations were stratified into an early group (<60 d) or a late group (>60 d). Univariate and multivariate logistical analyses were performed to identify potential risk factors related to reoperation.

RESULTS

A total of 627 patients met the inclusion criteria (PS = 540, Hb = 87). There was a statistically significant difference in the rate of reoperations between the PS (3.5%) and Hb groups (12.6%), P < 0.001. Early return to the OR occurred in 2.0% of the patients with PS compared with 3.4% in the Hb group, P = 0.43. Late returns to the OR occurred in 1.5% of PS group versus 9.2% of the Hb group, P < 0.001. Multivariate analysis revealed longer operating time as an independent risk factor for an unplanned return to the OR in patients treated with PSs (P < 0.05).

CONCLUSION

Our results suggest that patients with AIS treated with PS have decreased rates of unplanned return to the OR when compared with patients with Hb constructs. The majority of returns to the OR were early (<60 d) for the PS group compared with late (>60 d) for the Hb group. Longer operative times increased the risk of unplanned reoperation for the PS group.

LEVEL OF EVIDENCE

3.

Complications of surgical treatment of pediatric spinal deformities

Surgery in a child with spinal deformity is challenging. Although current orthopedic practice ensures good long-term surgical results, complications occur. Idiopathic scoliosis represents the most extensively investigated deformity of the pediatric spine. Nonidiopathic deformities of the spine are at higher risk for perioperative and long-term complications, mainly because of underlying comorbidities. A multidisciplinary treatment strategy is helpful to assure optimization of medical conditions before surgery. Awareness of complications that occur during or after spine surgery is essential to avoid a poor outcome and for future surgical decision making. This article summarizes the complications of surgical treatment of the growing spine.

Selection of fusion levels in adults with spinal deformity: an update

BACKGROUND CONTEXT

Adult spinal deformity (ASD) is commonly associated with disability and represents a challenging condition for physicians. Although surgical management has been reported as superior to conservative care, the choice of patient-specific optimal strategy has been poorly defined. A key question remains selection of fusion levels as this implies careful balance of risks and benefits.

PURPOSE

The aim of this review is to propose an update on current knowledge related to optimal fusion levels in the surgical treatment of ASD.

STUDY DESIGN

Literature review.

METHODS

Based on a comprehensive literature search, recent studies focusing on the management of ASD were reviewed to establish current concepts on fusion levels in the management of symptomatic ASD.

RESULTS

Despite numerous published studies, the management of ASD and specifically optimal fusion levels is incompletely defined. Described approaches carry benefits and risks. However, the need for detailed analysis and preoperative planning is confirmed as a prerequisite to obtaining realignment objectives and good outcomes.

CONCLUSIONS

The treatment of ASD is emerging as an important health-care issue of the 21st century because of prevalence and cost. Despite technical advances related to ASD surgery, complication rates remain elevated, particularly in the older population. Recent research, mostly driven by outcome measures, has improved our understanding of optimal treatment approaches to ASD. The development of a widely accepted classification system will help to share knowledge and improve our ability to treat these complex patients.

Repeat surgical interventions following "definitive" instrumentation and fusion for idiopathic scoliosis: five-year update on a previously published cohort

STUDY DESIGN

A retrospective case series.

OBJECTIVE

To identify the overall reoperation rate and factors contributing to reoperation in a recent 5-year cohort of patients (2003-2007) undergoing spinal deformity surgery. These patients were compared with a previously published 15-year cohort of consecutive patients (1988-2002) from the same institution to assess for any significant differences in reoperation rates.

SUMMARY OF BACKGROUND DATA

In a previously published report from this institution, the reoperation rate for patients with idiopathic scoliosis treated during a 15-year period (1988-2002) was 12.9%. That group was predominantly treated with first-generation TSRH (Medtronic, Memphis, TN) implants and CD implants. Lower profile, more rigid implant systems are now used along with refined techniques for correction of scoliosis deformity. We hypothesized that these factors would lead to lower rates of reoperation. METHODS.: The medical records of 452 consecutive patients (older than 9 yr) surgically treated for idiopathic scoliosis at one institution during 5 years (2003-2007) were reviewed to identify those who required reoperation.

RESULTS

The reoperation rate for this cohort was 7.5% (34 of 452 patients). Compared with the prior cohort, significant decreases were noted with regard to total reoperation rate as well as reoperation due to infection and pseudarthrosis. Trends were noted toward decreased rates of reoperation due to prominent implants, dislodged implants, and implant proximity to vital structures. Within the newer cohort, a trend toward decreased reoperation rate was also noted for lower profile implant systems compared with first-generation TSRH implants.

CONCLUSION

With the evolution of newer lower profile segmental implant systems that provide more rigid fixation and with the advancements in techniques for deformity correction, the repeat surgical intervention rate for idiopathic scoliosis has decreased.

Unanticipated revision surgery in adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective case series.

OBJECTIVE

The objective of this study was to share our experience in the surgical treatment of adolescent idiopathic scoliosis (AIS), specifically the rate of revision surgeries and their indications.

SUMMARY OF BACKGROUND DATA

Minimizing AIS surgical morbidity includes prevention of short- and long-term complications that could require an unanticipated revision. There have been an increasing number of reports about revision rates and their causes in AIS. This study summarizes the experience of a large patient population treated by a single surgeon in a single institution.

METHODS

All patients who underwent surgical treatment for AIS between 10 and 20 years of age during 1983 to 2005 were reviewed. All revision surgeries performed during the same period were searched. The indications for revision and type of procedure performed were recorded.

RESULTS

A total of 502 patients with AIS underwent spinal fusion with instrumentation at an average age of 14.3 years at initial surgery. In 485 patients, the surgery consisted of posterior-only spinal fusion. A total of 24 revision surgeries were performed for 23 patients (4.9%; cumulative probability of revision = 8%). The primary indications for revision were residual rib deformity (n = 8), instrumentation dislodgement (n = 4), compensatory curve progression (n = 3), junctional kyphosis (n = 3), and symptomatic implants (n = 3). One patient had a late infection. There was 1 case of pseudoarthrosis. One patient requested scar revision. There were no cases of neurological deficit.

CONCLUSION

In this single-surgeon series, revision after the index spinal fusion was required for a relatively low proportion of patients. The main indications for revision were residual rib deformity, hook dislodgment, and progression of the unfused compensatory curve.

The utility of erythrocyte sedimentation rate values and white blood cell counts after spinal deformity surgery in the early (≤3 months) post-operative period

PURPOSE

The erythrocyte sedimentation rate (ESR) and white blood cell (WBC) count are frequently obtained in the work-up of post-operative fever. However, their diagnostic utility depends upon comparison with normative peri-operative trends which have not yet been described. The purpose of this study is to define a range of erythrocyte sedimentation rates and white blood cell counts following spinal instrumentation and fusion in non-infected patients.

METHODS

Seventy-five patients underwent spinal instrumentation and fusion. The erythrocyte sedimentation rate and white blood cell count were recorded pre-operatively, at 3 and 7 days post-operatively, and at 1 and 3 months post-operatively.

RESULTS

Both erythrocyte sedimentation rate and white blood cell count trends demonstrated an early peak, followed by a gradual return to normal. Peak erythrocyte sedimentation rates occurred within the first week post-operatively in 98% of patients. Peak white blood cell counts occurred with the first week in 85% of patients. In the absence of infection, the erythrocyte sedimentation rate was abnormally elevated in 78% of patients at 1 month and in 53% of patients at 3 months post-operatively. The white blood cell count was abnormally elevated in only 6% of patients at 1 month post-operatively. Longer surgical time was associated with elevated white cell count at 1 week post-operatively. The fusion of more vertebral levels had a negative relationship with elevated erythrocyte sedimentation rate at 1 week post-operatively. The anterior surgical approach was associated with significantly lower erythrocyte sedimentation rate at 1 month post-operatively and with lower white cell count at 1 week post-operatively.

CONCLUSION

In non-infected spinal fusion surgeries, erythrocyte sedimentation rates are in the abnormal range in 78% of patients at 1 month and in 53% of patients at 3 months post-operatively, suggesting that the erythrocyte sedimentation rate is of limited diagnostic value in the early post-operative period.

Clinical and demographic characteristics of online community members--does it represent reality?

BACKGROUND

The decision to undergo surgery for scoliosis is shared between the physician, patient, and family. In an effort to obtain objective data regarding scoliosis surgery, patients often use the Internet, which includes sharing experiences in online communities. To this end, physicians have limited knowledge about disease-specific online communities.

PURPOSE

To analyze the clinical and demographic characteristics of patients who use disease-specific online communities.

STUDY DESIGN

A retrospective clinical study.

PATIENT SAMPLE

One hundred ninety-five patients with scoliosis who are also members of a popular scoliosis-specific online community.

MAIN OUTCOME MEASURES

Five domains of the Scoliosis Research Society-22 (SRS-22) quality-of-life questionnaire: function, pain, mental health, self-image, and satisfaction.

METHODS

An online questionnaire was submitted by members of a scoliosis-specific online community. One hundred ninety-five patients with scoliosis fulfilled the inclusion criteria, which represented 54% of all active members who have logged into this community during the time of data collection. A descriptive analysis was performed for demographic and clinical characteristics.

RESULTS

Analysis revealed a bimodal age distribution. Most online members were female (74%) and underwent surgical treatment (78%). Of all surgical patients, 52% had surgery between the age of 10 and 18 years. The average time since surgery (follow-up) was 10 years and 9 months. A revision rate of 17% was calculated, which increased with longer follow-up. Five of nine surgical subgroups significantly outperformed nonsurgical patients in regards of SRS-22 total scores.

CONCLUSION

This study supports that members from an online scoliosis community may be the representative sample of the general scoliosis patient population. The information obtained may be useful for physicians to understand patient concerns and mitigate treatment expectations when counseling patients.

Anticipating complications in pediatric deformity surgery: is any preparation necessary in healthy children?

STUDY DESIGN

Review article.

OBJECTIVE

The goal of this review article is to discuss the steps taken to minimize and reduce complications from surgery in children and adolescents with idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

A majority of children and adolescents with idiopathic scoliosis are otherwise healthy. Most lead relatively normal active lives. Assessing the functional impact of surgery is difficult due to the fact that most patients function at a high level before surgery. Surgery is geared to prevent the long-term problems associated with scoliosis. Complications do occur in the treatment of idiopathic scoliosis. Understanding the nature of these complications may help to improve long-term outcome.

METHODS

Children and adolescents with idiopathic scoliosis were assessed using radiographs, magnetic resonance imaging, computed tomography scans, pain assessment, pulmonary assessment, surgical notes, history, and physical examinations.

RESULTS

No true agreement exists in the literature for standard preoperative assessment of idiopathic scoliosis to reduce and prevent adverse events and surgical complications.

CONCLUSION

The treating surgeon must be aware of the potential risks, adverse events, and complications associated with the procedure, and must be able to convey this to the patient and their family in a clear and concise manner.

Revision spine surgery to manage pediatric deformity

Revision deformity surgery in the growing child is a complex clinical problem. Excellent outcomes can be obtained with meticulous patient evaluation followed by well-planned and well-executed treatment. A multidisciplinary team is crucial to a satisfactory overall outcome. Diagnosis of failed index spine fusion requires a thorough patient history and physical examination, careful patient assessment, and imaging between the index procedure and the presentation for revision and confirmatory testing that validates the diagnosis. Revision surgery may include irrigation and débridement, implant removal, or revision spine fusion with deformity correction. Correction may require either an anterior approach or a posterior approach with osteotomy. For best results, the planned revision must address the mechanism of the failure of the index procedure. If the symptoms or observations are not explained by the diagnosis, then alternative etiologies should be considered.

Pediatric revision spinal deformity surgery: issues and complications

STUDY DESIGN

A review of issues and concerns associated with pediatric revision surgery.

OBJECTIVES

To describe: (1) the incidence, causes, and prevention of spine revision surgery in the pediatric population; and (2) the preoperative planning and imaging necessary for such surgeries and the associated intraoperative and technical complications (e.g., infection, blood loss, and incomplete deformity correction).

SUMMARY OF BACKGROUND DATA

Revision surgery may be needed for pediatric spinal deformity because of many factors. This article describes the assessment and performance of revision surgery to optimize results.

METHODS

The literature and the author's personal experience were reviewed.

RESULTS

Rates of reoperation range from 4% to 25% for adolescent idiopathic scoliosis and are higher for neuromuscular or syndromic diagnoses. The most common indications for revision are infection, increased deformity, late operative site pain, pseudarthrosis, and implant dislodgement. Because revision cases are unique, preoperative planning should include a review of previous records and imaging for a thorough understanding of the bony and neurologic anatomy and instrumentation. Preoperative discussion with colleagues may help prevent the need for additional revision. Measures to minimize blood loss should be taken. Deformity correction may include mobilization by multiple osteotomies for long sweeping curves, or focal osteotomies (e.g., vertebral column resection or pedicle subtraction osteotomies) for focal deformity. If fusing additional levels, instrumentation should have adequate fixation and should connect to existing anchors so that the corrective force can be applied to the site of deformity. The possibility of occult infection should be considered; in the event of a late deep infection, options include removing implants and debriding the spine. However, there is a risk of increased deformity in the coronal and sagittal planes after implant removal. Because revision surgery itself may have a higher subsequent reoperation rate, thorough preparation should be done to ensure success.

CONCLUSION

Cases of spine revision surgery in the pediatric population are best undertaken by an experienced surgeon and should involve thorough preoperative planning, proper equipment, and skilled assistance.

Infection rate after spine surgery in cerebral palsy is high and impairs results: multicenter analysis of risk factors and treatment

Infection is a serious complication of surgery to correct scoliosis in patients with cerebral palsy (CP). We obtained multicenter representative figures for deep and superficial infection rates, analyzed risk factors and treatment outcomes, and compared deformity correction relative to infection. We retrospectively reviewed 157 patients who had posterior spinal fusion for CP at one of eight centers. Preoperative and intraoperative variables were subjected to multivariate analysis to determine factors predictive of infection. There were 16 wound infections (10%; nine deep, seven superficial). Only two study factors predicted infection: higher preoperative white blood cell count (8.5 versus 6.4 [in those without infection] x 10(3)) and use of a unit rod (15% versus 5% for bent rods). Fourteen patients underwent irrigation and débridement procedures. Five infections required 2 months or longer to resolve. Two had implant removal. Final curve correction was lower for those with deep infections than those without (67% versus 53%, respectively). We noted a trend toward greater percentages of pain at last followup in those with deep infection than in those without infection (50% versus 18%, respectively) but the study was not adequately powered to confirm this point. Our infection rate in scoliosis surgery for CP was higher than that for most elective spinal deformity surgery.

LEVEL OF EVIDENCE

Level III, retrospective case-control study. See Guidelines for Authors for a complete description of levels of evidence.

Revision rates following primary adult spinal deformity surgery: six hundred forty-three consecutive patients followed-up to twenty-two years postoperative

STUDY DESIGN

Retrospective study.

OBJECTIVE

To analyze the prevalence of and reasons for unanticipated revision surgery in an adult spinal deformity population treated at one institution.

SUMMARY OF BACKGROUND DATA

No recent studies exist that analyze the rate or reason for unanticipated revision surgery for adult spinal deformity patients over a long period.

METHODS

All patients presenting for primary instrumented spinal fusion with a diagnosis of adult deformity at a single institution from 1985 to 2008 were reviewed using a prospectively acquired database. All surgical patients with instrumented fusion of > or =5 levels using hooks, hybrid, or screw-only constructs were identified. Patient charts and radiographs were reviewed to provide information as to the indication for initial and any subsequent reoperation. A total of 643 patients underwent primary instrumented fusion for a diagnosis of adult idiopathic scoliosis (n = 432), de novo degenerative scoliosis (n = 104), adult kyphotic disease (n = 63), or neuromuscular scoliosis (n = 45). The mean age was 37.9 years (range, 18-84). Mean follow-up for the entire cohort was 4.7 years, and 8.2 years for the subset of the cohort requiring reoperation (range, 1 month-22.3 years).

RESULTS

A total of 58 of 643 patients (9.0%) underwent at least one revision surgery and 15 of 643 (2.3%) had more than one revision (mean 1.3; range, 1-3). The mean time to the first revision was 4.0 years (range, 1 week-19.7 years). The most common reasons for revision were pseudarthrosis (24/643 = 3.7%; 24/58 = 41.4%), curve progression (13/643 = 2.0%; 13/58 = 20.7%), infection (9/643 = 1.4%; 9/58 = 15.5%), and painful/prominent implants (4/643 = 0.6%; 4/58 = 6.9%). Uncommon reasons consisted of adjacent segment degeneration (3), implant failure (3), neurologic deficit (1), and coronal imbalance (1). Revision rates over the follow-up period were: 0 to 2 years (26/58 = 44.8%), 2 to 5 years (17/58 = 29.3%), 5 to 10 years (7/58 = 12.1%), >10 years (8/58 = 13.8%).

CONCLUSION

Repeat surgical intervention following definitive spinal instrumented fusion for primary adult deformity performed at a single institution demonstrated a relatively low rate of 9.0%. The most common reasons for revision were predictable and included pseudarthrosis, proximal or distal curve progression, and infection.

Analysis of instrumentation/fusion survivorship without reoperation after primary posterior multiple anchor instrumentation and arthrodesis for idiopathic scoliosis

BACKGROUND

During the past 25 years, spinal instrumentation systems and surgical techniques used to treat idiopathic scoliosis have evolved, achieving fewer patient restrictions during arthrodesis healing, shorter constructs, and better correction. The purposes of this retrospective comparative study were to determine the survivorship of the implant/fusion without reoperation and the risk factors influencing such survival.

METHODS

From 1989 through 2002, 208 consecutive patients (index patient included, age 10-20 years) underwent primary posterior instrumentation and arthrodesis with the same multiple anchor implant system by one surgeon, a co-designer of the system. Two hundred seven were followed for more than 2 years; reoperation status was available for them at an average follow-up of 8.3 years. Twenty-one independent demographic, deformity, instrumentation, and process variables possibly influencing the need for reoperation were studied by comparing the reoperated group with the unreoperated group.

RESULTS

Nineteen patients (9.2%) had reoperation; 16 (7.7%) were for indications related to posterior spine instrumentation. Survival of the implant/fusion without reoperation for spine instrumentation-related indications was 96% (95% confidence interval [CI], 93.2-98.7%) at 5 years, 91.6% (95% CI, 86.9-96.3%) at 10 years, 87.1% (95% CI, 79.5-94.6%) at 15 years, and 73.7% (95% CI, 48.6-98.6%) at 16 years, when the number at risk was nine. Reoperation need was significantly influenced by two implant variables: transverse connector design (p=.0012) and the lower instrumented vertebra anchors used (p=.0004). At 9 years, the longest interval allowing comparison, survival of the implant/fusion without reoperation for these two variables was 100% (six subjects at risk) compared to 82% (95% CI, 74.2-90.3%) with 59 patients still at risk for reoperation for those who did not have them, p=.0014.

CONCLUSIONS

The most stable lower instrumented vertebra anchor configuration, bilateral pedicle screws, and the stronger transverse connector design, closed drop entry, provided the best survival of the implant/fusion without reoperation with this system and the techniques used at 9-year follow-up. We hope that this post-market study using survivorship techniques will be a guide for studies of other spinal implants.

Posterior spinal fusion versus anterior/posterior spinal fusion for adolescent idiopathic scoliosis: a decision analysis

STUDY DESIGN

Decision analysis.

OBJECTIVE

To determine the optimum surgical strategy for skeletally immature females with large idiopathic spinal curves.

SUMMARY OF BACKGROUND DATA

Curve progression after posterior instrumentation is a concern for skeletally immature patients with large scoliotic curves. Anterior/posterior spinal fusion is preferred by some surgeons to treat this specific population. Combined fusions carry higher inherent risk of pulmonary and neurologic complication. Large data sets of complication rates have only recently become available. To date no direct comparison between the 2 approaches has been made using the most recent data.

METHODS

A model was constructed to compare the effectiveness of the 2 surgical approaches. Rates of complications and revisions were acquired from the surgical literature. Utilities were obtained from earlier studies and conversion of SF-36 data for the health states included the model. Effectiveness was measured by quality-adjusted life years. Sensitivity analysis was used to test the robustness of the model and identify variables that impact the clinical decision.

RESULTS

The results of our model showed anterior/posterior spinal fusion to be the preferred surgical approach for treating scoliosis in skeletally immature females. Anterior/posterior spinal fusion resulted in a net gain of 6.17 quality-adjusted life years. Variables that impacted the results of the model were the probability of curve progression for the 2 surgical approaches and the surgical mortality of anterior/posterior spinal fusion. Curve progression rates vary considerably in the literature and are based on small samples and dated surgical techniques.

CONCLUSION

Our model favors anterior/posterior spinal fusion for surgical correction of large thoracic curves in skeletally immature females. The probability of curve progression after spinal fusion is the main variable that dictates the optimal surgical approach and rates in the literature are based on outdated surgical instrumentation. Future observational studies are warranted to acquire more accurate curve progression rates.

Revision surgery after primary spine fusion for idiopathic scoliosis

STUDY DESIGN

Retrospective case series.

OBJECTIVE

The objective of this study was to review the overall prevalence of, and indications for, reoperations after the index spine fusion for idiopathic scoliosis at our center.

SUMMARY OF BACKGROUND DATA

Spine fusions for idiopathic scoliosis are expected to be the final therapeutic intervention in management. In a recent publication in 2006, reoperations after index spine fusion for idiopathic scoliosis were reported in 12.9% of patients at a single institution (n = 1046).

METHODS

A spinal deformity database search at our center identified all primary anterior, posterior, and circumferential spinal fusions performed for idiopathic scoliosis (1985-2003). A total of 1057 patients were identified whose mean age was 14.4 years (7-22 years) with minimum 2 year follow-up after index surgery. Study cohort consisted patients who underwent reoperation for any reason after index fusion procedure.

RESULTS

Of the 1057 spinal fusions for idiopathic scoliosis, 41 (3.9%) underwent reoperation. Primary surgeries were: 11 anterior spinal fusions, 25 posterior spinal fusions, and 5 circumferential spinal fusions. Mean follow-up was 5.7 years (2-10.8). Forty-seven additional procedures were performed during 46 reoperations at an average of 26 months after index procedure (1 week-73 months). Of the 47 reoperations, 20 (43%) were revision spinal fusions (for pseudarthroses, uninstrumented curve progression or junctional kyphosis), 16 (34%) because of infections (5 acute, 11 chronic), 7 (15%) for implant removals due to pain and/or prominence (4 complete, 3 partial), 2 (4%) were revision of loosened implants, and 2 (4%) were elective thoracoplasties.

CONCLUSION

This study documented a 3.9% overall reoperation rate at our medical center, a 3-fold lower reoperation rate than the previously reported 12.9%. The most common reoperations were for infections (34%), pseudarthroses (26%), and postoperative curve progression of the adjacent unfused spine (17%).

Inpatient complications, mortality, and discharge disposition after surgical correction of idiopathic scoliosis: a national perspective

BACKGROUND CONTEXT

Information about complications and mortality after surgery for correction of idiopathic scoliosis has been largely derived from single-institution series. Regional or national studies have been lacking.

PURPOSE

To report inpatient mortality, complications, and discharge disposition after surgical correction of idiopathic scoliosis on a national level.

STUDY DESIGN

Retrospective cohort study using National Inpatient Sample (NIS) administrative data.

PATIENT SAMPLE

All patients in the NIS with the primary diagnosis of idiopathic scoliosis who underwent a spinal fusion between 1993 and 2002 were included.

OUTCOME MEASURES

Inpatient complication rate, mortality rate, and adverse outcome defined by death or discharge to institution other than home.

METHODS

Outcome measures were abstracted from the NIS. Univariate and multivariate analyses were performed to analyze the effects of patient and hospital characteristics on outcome measures.

RESULTS

The NIS was used to identify 51,911 patients who underwent spinal fusion for idiopathic scoliosis in the United States from 1993 to 2002. The total inhospital complication rate was 14.9% for pediatric patients and 25.1% for adult patients. The inhospital mortality rate was 0.17% and 0.40% for pediatric and adult patients, respectively. Adverse outcome was noted in 2.3% of pediatric patients and 20.4% of adult patients. Pulmonary and postoperative hemorrhages/hematomas were the most common complications reported. Multivariate analysis for complications showed that morbidity was significantly lower for pediatric patients (odds ratio [OR] = 0.80; confidence interval [CI] = 0.68-0.94) and female patients (OR = 0.77; CI = 0.68-0.88). Patients with a preoperative comorbidity were 1.53 (CI = 1.32-1.76) times more likely to develop a complication. A single postoperative complication increased the mean length of stay by more than 2 days and increased the mortality rate, adverse outcome, and hospital charges significantly.

CONCLUSIONS

We have provided a national perspective on inpatient complications, mortality, and discharge disposition after spinal fusion for idiopathic scoliosis in the United States. The significant negative effects of postoperative complications on mortality and resource utilization have been demonstrated. Furthermore, we have identified adult age, male gender, and preoperative comorbidity as important risk factors and defined their impact on patient outcomes.

Rate of complications in scoliosis surgery - a systematic review of the Pub Med literature

Background

Spinal fusion surgery is currently recommended when curve magnitude exceeds 40–45 degrees. Early attempts at spinal fusion surgery which were aimed to leave the patients with a mild residual deformity, failed to meet such expectations. These aims have since been revised to the more modest goals of preventing progression, restoring 'acceptability' of the clinical deformity and reducing curvature.

In view of the fact that there is no evidence that health related signs and symptoms of scoliosis can be altered by spinal fusion in the long-term, a clear medical indication for this treatment cannot be derived. Knowledge concerning the rate of complications of scoliosis surgery may enable us to establish a cost/benefit relation of this intervention and to improve the standard of the information and advice given to patients. It is also hoped that this study will help to answer questions in relation to the limiting choice between the risks of surgery and the "wait and see – observation only until surgery might be recommended", strategy widely used. The purpose of this review is to present the actual data available on the rate of complications in scoliosis surgery.

Materials and methods

Search strategy for identification of studies; Pub Med and the SOSORT scoliosis library, limited to English language and bibliographies of all reviewed articles. The search strategy included the terms; 'scoliosis'; 'rate of complications'; 'spine surgery'; 'scoliosis surgery'; 'spondylodesis'; 'spinal instrumentation' and 'spine fusion'.

Results

The electronic search carried out on the 1^st February 2008 with the key words "scoliosis", "surgery", "complications" revealed 2590 titles, which not necessarily attributed to our quest for the term "rate of complications". 287 titles were found when the term "rate of complications" was used as a key word. Rates of complication varied between 0 and 89% depending on the aetiology of the entity investigated. Long-term rates of complications have not yet been reported upon.

Conclusion

Scoliosis surgery has a varying but high rate of complications. A medical indication for this treatment cannot be established in view of the lack of evidence. The rate of complications may even be higher than reported. Long-term risks of scoliosis surgery have not yet been reported upon in research. Mandatory reporting for all spinal implants in a standardized way using a spreadsheet list of all recognised complications to reveal a 2-year, 5-year, 10-year and 20-year rate of complications should be established. Trials with untreated control groups in the field of scoliosis raise ethical issues, as the control group could be exposed to the risks of undergoing such surgery.