Breton Line

Prospective multicenter assessment of perioperative and minimum 2-year postoperative complication rates associated with adult spinal deformity surgery

OBJECTIVE Although multiple reports have documented significant benefit from surgical treatment of adult spinal deformity (ASD), these procedures can have high complication rates. Previously reported complications rates associated with ASD surgery are limited by retrospective design, single-surgeon or single-center cohorts, lack of rigorous data on complications, and/or limited follow-up. Accurate definition of complications associated with ASD surgery is important and may serve as a resource for patient counseling and efforts to improve the safety of patient care. The authors conducted a study to prospectively assess the rates of complications associated with ASD surgery with a minimum 2-year follow-up based on a multicenter study design that incorporated standardized data-collection forms, on-site study coordinators, and regular auditing of data to help ensure complete and accurate reporting of complications. In addition, they report age stratification of complication rates and provide a general assessment of factors that may be associated with the occurrence of complications. METHODS As part of a prospective, multicenter ASD database, standardized forms were used to collect data on surgery-related complications. On-site coordinators and central auditing helped ensure complete capture of complication data. Inclusion criteria were age older than 18 years, ASD, and plan for operative treatment. Complications were classified as perioperative (within 6 weeks of surgery) or delayed (between 6 weeks after surgery and time of last follow-up), and as minor or major. The primary focus for analyses was on patients who reached a minimum follow-up of 2 years. RESULTS Of 346 patients who met the inclusion criteria, 291 (84%) had a minimum 2-year follow-up (mean 2.1 years); their mean age was 56.2 years. The vast majority (99%) had treatment including a posterior procedure, 25% had an anterior procedure, and 19% had a 3-column osteotomy. At least 1 revision was required in 82 patients (28.2%). A total of 270 perioperative complications (145 minor; 125 major) were reported, with 152 patients (52.2%) affected, and a total of 199 delayed complications (62 minor; 137 major) were reported, with 124 patients (42.6%) affected. Overall, 469 complications (207 minor; 262 major) were documented, with 203 patients (69.8%) affected. The most common complication categories included implant related, radiographic, neurological, operative, cardiopulmonary, and infection. Higher complication rates were associated with older age (p = 0.009), greater body mass index (p ≤ 0.031), increased comorbidities (p ≤ 0.007), previous spine fusion (p = 0.029), and 3-column osteotomies (p = 0.036). Cases in which 2-year follow-up was not achieved included 2 perioperative mortalities (pulmonary embolus and inferior vena cava injury). CONCLUSIONS This study provides an assessment of complications associated with ASD surgery based on a prospective, multicenter design and with a minimum 2-year follow-up. Although the overall complication rates were high, in interpreting these findings, it is important to recognize that not all complications are equally impactful. This study represents one of the most complete and detailed reports of perioperative and delayed complications associated with ASD surgery to date. These findings may prove useful for treatment planning, patient counseling, benchmarking of complication rates, and efforts to improve the safety and cost-effectiveness of patient care.

Evidence based medicine : Analysis of scheuermann kyphosis

Study Design. A review of the current literature using evidence-based medicine (EBM) regarding etiology, natural history, and treatment of Scheuermann kyphosis. Objective. To provide current concepts for the rational evaluation and treatment of Scheuermann kyphosis supported by EBM. Summary of Background Data. The literature concerning etiology, natural history, and treatment of Scheuermann disease has mixed views and recommendations, most of which are not strongly supported with levels of evidence. Methods. A thorough database search was performed in order to obtain the best current information and levels of evidence on etiology, natural history, and treatment options for Scheuermann kyphosis based on EBM criteria. Results and Conclusion. Scheuermann kyphosis is the most common cause of hyperkyphosis in adolescence. Its true etiology remains unknown, but there appears to be a strong genetic as well as an environmental contribution. The kyphotic deformity is frequently attributed to “poor posture” resulting in delayed diagnosis, and treatment indications remain debated because the natural history has not been clearly defined. When recognized early in adolescence with progressive kyphosis, bracing treatment will usually result in modest correction of the deformity. Symptomatic adolescents with severe deformity have demonstrated significant deformity correction following surgical intervention; however, clinical outcomes data are not yet available, and the studies available do not have strong levels of evidence.

Incidence, mode, and location of acute proximal junctional failures after surgical treatment of adult spinal deformity.

Study Design. Multicenter, retrospective series. Objective. To analyze the incidence, mode, and location of acute proximal junctional failures (APJFs) after surgical treatment of adult spinal deformity. Summary of Background Data. Early proximal junctional failures above adult deformity constructs are a serious clinical problem; however, the incidence and nature of early APJFs remain unclear. Methods. A total of 1218 consecutive adult spinal deformity surgeries across 10 deformity centers were retrospectively reviewed to evaluate the incidence and nature of APJF, defined as any of the following within 28 weeks of index procedure: minimum 15° post-operative increase in proximal junctional kyphosis, vertebral fracture of upper instrumented vertebrae (UIV) or UIV + 1, failure of UIV fixation, or need for proximal extension of fusion within 6 months of surgery. Results. Sixty-eight APJF cases were identified out of 1218 consecutive surgeries (5.6%). Patients had a mean age of 63 years (range, 26–82 yr), mean fusion levels of 9.8 (range, 4–18), and mean time to APJF of 11.4 weeks (range, 1.5–28 wk). Fracture was the most common failure mode (47%), followed by soft-tissue failure (44%). Failures most often occurred in the thoracolumbar region (TL-APJF) compared with the upper thoracic region (UT-APJF), with 66% of patients experiencing TL-APJF compared with 34% experiencing UT-APJF. Fracture was significantly more common for TL-APJF relative to UT-APJF (P = 0.00), whereas soft-tissue failure was more common for UT-APJF (P < 0.02). Patients experiencing TL-APJF were also older (P = 0.00), had fewer fusion levels (P = 0.00), and had worse postoperative sagittal vertical axis (P < 0.01). Conclusion. APJFs were identified in 5.6% of patients undergoing surgical treatment of adult spinal deformity, with failures occurring primarily in the TL region of the spine. There is evidence that the mode of failure differs depending on the location of UIV, with TL failures more likely due to fracture and UT failures more likely due to soft-tissue failures.

Outcomes of Operative and Nonoperative Treatment for Adult Spinal Deformity: A Prospective, Multicenter, Propensity-Matched Cohort Assessment With Minimum 2-Year Follow-up

BACKGROUND High-quality studies that compare operative and nonoperative treatment for adult spinal deformity (ASD) are needed. OBJECTIVE To compare outcomes of operative and nonoperative treatment for ASD. METHODS This is a multicenter, prospective analysis of consecutive ASD patients opting for operative or nonoperative care. Inclusion criteria were age >18 years and ASD. Operative and nonoperative patients were propensity matched with the baseline Oswestry Disability Index, Scoliosis Research Society-22r, thoracolumbar/lumbar Cobb angle, pelvic incidence-to-lumbar lordosis mismatch (PI-LL), and leg pain score. Analyses were confined to patients with a minimum of 2 years of follow-up. RESULTS Two hundred eighty-six operative and 403 nonoperative patients met the criteria, with mean ages of 53 and 55 years, 2-year follow-up rates of 86% and 55%, and mean follow-up of 24.7 and 24.8 months, respectively. At baseline, operative patients had significantly worse health-related quality of life (HRQOL) based on all measures assessed (P < .001) and had worse deformity based on pelvic tilt, pelvic incidence-to-lumbar lordosis mismatch, and sagittal vertical axis (P ≤ .002). At the minimum 2-year follow-up, all HRQOL measures assessed significantly improved for operative patients (P < .001), but none improved significantly for nonoperative patients except for modest improvements in the Scoliosis Research Society-22r pain (P = .04) and satisfaction (P < .001) domains. On the basis of matched operative-nonoperative cohorts (97 in each group), operative patients had significantly better HRQOL at follow-up for all measures assessed (P < .001), except Short Form-36 mental component score (P = .06). At the minimum 2-year follow-up, 71.5% of operative patients had ≥1 complications. CONCLUSION Operative treatment for ASD can provide significant improvement of HRQOL at a minimum 2-year follow-up. In contrast, nonoperative treatment on average maintains presenting levels of pain and disability. ABBREVIATIONS ASD, adult spinal deformityHRQOL, health-related quality of lifeLL, lumbar lordosisMCID, minimal clinically important differenceNRS, numeric rating scaleODI, Oswestry Disability IndexPI, pelvic incidenceSF-36, Short Form-36SRS-22r, Scoliosis Research Society-22rSVA, sagittal vertical axis.

The Health Impact of Symptomatic Adult Spinal Deformity: Comparison of Deformity Types to United States Population Norms and Chronic Diseases

Study Design. A retrospective analysis of a prospective, multicenter database. Objective. The aim of this study was to evaluate the health impact of symptomatic adult spinal deformity (SASD) by comparing Standard Form Version 2 (SF-36) scores for SASD with United States normative and chronic disease values. Summary of Background Data. Recent data have identified radiographic parameters correlating with poor health-related quality of life for SASD. Disability comparisons between SASD patients and patients with chronic diseases may provide further insight to the disease burden caused by SASD. Methods. Consecutive SASD patients, with no history of spine surgery, were enrolled into a multicenter database and evaluated for type and severity of spinal deformity. Baseline SF-36 physical component summary (PCS) and mental component summary (MCS) values for SASD patients were compared with reported U.S. normative and chronic disease SF-36 scores. SF-36 scores were reported as normative-based scores (NBS) and evaluated for minimally clinical important difference (MCID). Results. Between 2008 and 2011, 497 SASD patients were prospectively enrolled and evaluated. Mean PCS for all SASD was lower than U.S. total population (ASD = 40.9; US = 50; P < 0.05). Generational decline in PCS for SASD patients with no other reported comorbidities was more rapid than U.S. norms (P < 0.05). PCS worsened with lumbar scoliosis and increasing sagittal vertical axis (SVA). PCS scores for patients with isolated thoracic scoliosis were similar to values reported by individuals with chronic back pain (45.5 vs 45.7, respectively; P > 0.05), whereas patients with lumbar scoliosis combined with severe sagittal malalignment (SVA >10 cm) demonstrated worse PCS scores than values reported by patients with limited use of arms and legs (24.7 vs 29.1, respectively; P < 0.05). Conclusions. SASD is a heterogeneous condition that, depending upon the type and severity of the deformity, can have a debilitating impact on health often exceeding the disability of more recognized chronic diseases. Health care providers must be aware of the types of SASD that correlate with disability to facilitate appropriate diagnosis, treatment, and research efforts. Level of Evidence: 3.

Does Recombinant Human Bone Morphogenetic Protein-2 Use in Adult Spinal Deformity Increase Complications and Are Complications Associated With Location of rhbmp-2 Use? A Prospective, Multicenter Study of 279 Consecutive Patients

Study Design. Multicenter, prospective analysis of consecutive patients with adult spinal deformity (ASD). Objective. Evaluate complications associated with recombinant human bone morphogenetic protein-2 (rhBMP-2) use in ASD. Summary of Background Data. Off-label rhBMP-2 use is common; however, underreporting of rhBMP-2 associated complications has been recently scrutinized. Methods. Patients with ASD consecutively enrolled into a prospective, multicenter database were evaluated for type and timing of acute perioperative complications. Inclusion criteria: age 18 years and older, ASD, spinal arthrodesis of more than 4 levels, and 3 or more months of follow-up. Patients were divided into those receiving rhBMP-2 (BMP) or no rhBMP-2 (NOBMP). BMP divided into location of use: posterior (PBMP), interbody (IBMP), and interbody + posterior spine (I + PBMP). Correlations between acute perioperative complications and rhBMP-2 use including total dose, dose/level, and location of use were evaluated. Results. A total of 279 patients (mean age: 57 yr; mean spinal levels fused: 12.0; and mean follow-up: 28.8 mo) met inclusion criteria. BMP (n = 172; average posterior dose = 2.5 mg/level, average interbody dose = 5 mg/level) had similar age, smoking history, previous spine surgery, total spinal levels fused, estimated blood loss, and duration of hospital stay as NOBMP (n = 107; P > 0.05). BMP had greater Charlson Comorbidity Index (1.9 vs. 1.2), greater scoliosis (43° vs. 38°), longer operative time (488.2 vs. 414.6 min), more osteotomies per patient (4.0 vs. 1.6), and greater percentage of anteroposterior fusion (APSF; 20.9% vs. 8.4%) than NOBMP, respectively (P < 0.05). BMP had more total complications per patient (1.4 vs. 0.6) and more minor complications per patient (0.9 vs. 0.2) than NOBMP, respectively (P < 0.05). NOBMP had more complications requiring surgery per patient than BMP (0.3 vs. 0.2; P < 0.05). Major, neurological, wound, and infectious complications were similar for NOBMP, BMP, PBMP, IBMP, and I + PBMP (P > 0.05). Multivariate analysis demonstrated small to nonexistent correlations between rhBMP-2 use and complications. Conclusion. RhBMP-2 use and location of rhBMP-2 use in ASD surgery, at reported doses, do not increase acute major, neurological, or wound complications. Research is needed for higher rhBMP-2 dosing and long-term follow-up. Level of Evidence: 2

Development of Validated Computer-based Preoperative Predictive Model for Proximal Junction Failure (PJF) or Clinically Significant PJK With 86% Accuracy Based on 510 ASD Patients With 2-year Follow-up.

Study Design. A retrospective review of large, multicenter adult spinal deformity (ASD) database. Objective. The aim of this study was to build a model based on baseline demographic, radiographic, and surgical factors that can predict clinically significant proximal junctional kyphosis (PJK) and proximal junctional failure (PJF). Summary of Background Data. PJF and PJK are significant complications and it remains unclear what are the specific drivers behind the development of either. There exists no predictive model that could potentially aid in the clinical decision making for adult patients undergoing deformity correction. Methods. Inclusion criteria: age ≥18 years, ASD, at least four levels fused. Variables included in the model were demographics, primary/revision, use of three-column osteotomy, upper-most instrumented vertebra (UIV)/lower-most instrumented vertebra (LIV) levels and UIV implant type (screw, hooks), number of levels fused, and baseline sagittal radiographs [pelvic tilt (PT), pelvic incidence and lumbar lordosis (PI-LL), thoracic kyphosis (TK), and sagittal vertical axis (SVA)]. PJK was defined as an increase from baseline of proximal junctional angle ≥20° with concomitant deterioration of at least one SRS-Schwab sagittal modifier grade from 6 weeks postop. PJF was defined as requiring revision for PJK. An ensemble of decision trees were constructed using the C5.0 algorithm with five different bootstrapped models, and internally validated via a 70 : 30 data split for training and testing. Accuracy and the area under a receiver operator characteristic curve (AUC) were calculated. Results. Five hundred ten patients were included, with 357 for model training and 153 as testing targets (PJF: 37, PJK: 102). The overall model accuracy was 86.3% with an AUC of 0.89 indicating a good model fit. The seven strongest (importance ≥0.95) predictors were age, LIV, pre-operative SVA, UIV implant type, UIV, pre-operative PT, and pre-operative PI-LL. Conclusion. A successful model (86% accuracy, 0.89 AUC) was built predicting either PJF or clinically significant PJK. This model can set the groundwork for preop point of care decision making, risk stratification, and need for prophylactic strategies for patients undergoing ASD surgery. Level of Evidence: 3

A Posterior Tether for Fusionless Modulation of Sagittal Plane Growth in a Sheep Model

Study Design. This was an in vivo and in vitro investigation of a minimally invasive posterior tether system for fusionless modulation of sagittal plane growth in an immature sheep model. Objective. To determine whether fusionless modulation of spinal growth in the sagittal plane of an immature sheep model can be successfully performed. Summary of Background Data. Scheuermann’s disease has been reported to affect 1% to 8% of the pediatric population. Varying degrees of spinal bone growth modulation has been successfully performed in the coronal plane of animal models. This represents the first attempt to modulate spinal growth in the sagittal plane in an animal model. Modulation of spinal growth in the sagittal plane may play a role in the treatment of pediatric kyphosis when brace treatment is unsuccessful. Methods. There were nine immature sheep posteriorly tethered and five control animals, all with identical follow-ups. Pedicle screws were placed in adjacent vertebrae, bilaterally, at the thoracolumbar junction and the lower lumbar spine. Polyethylene cords were passed subcutaneously, and tensioned to 20 lbs. Tethers were released in four sheep at 6 months and four at 12 months. At 12 months and 2 weeks, all animals were sacrificed. Results. At 13 months after surgery, the tethered groups had significantly less kyphosis and vertebral body wedging than the control group. In both the tethered groups, at 13 months after surgery, there was significantly less vertebral body wedging compared with the preoperative values. There was no evidence of facet arthropathy, but heterotopic ossification was seen in several specimens. Tethered spines had significantly less motion than control spines. Histologic evaluation demonstrated no detrimental results. Conclusions. Fusionless modulation of sagittal plane growth in an immature sheep model was successfully performed with changes in the overall sagittal profile of the instrumented segments and vertebral body wedging. Increased stiffness of the instrumented segments posttether release was thought to be related to heterotopic ossification. Results suggest that this may be a potential treatment for adolescents with Scheuermann’s disease.

Functional limitations due to lumbar stiffness in adults with and without spinal deformity

Study Design. Cross-sectional analysis. Objective. To compare Lumbar Stiffness Disability Index (LSDI) scores between asymptomatic adults and patients with spinal deformity. Summary of Background Data. The LSDI was designed and validated as a tool to assess functional impacts of lumbar spine stiffness and diminished spinal flexibility. Baseline disability levels of patients with adult spinal deformity (ASD) are high as measured by multiple validated outcome tools. Baseline lumbar stiffness-related disability has not been assessed in adults with and without spinal deformity. Methods. The LSDI and Scoliosis Research Society-22r (SRS-22r) were submitted to a group of asymptomatic adult volunteers. Additionally, a multicenter cross-sectional cohort analysis of patients with ASD from 10 centers was conducted. Baseline LSDI and SRS-22r were completed for both operatively and nonoperatively treated patients with deformity. Results. The LSDI was completed by 176 asymptomatic volunteers and 693 patients with ASD. Mean LSDI score for asymptomatic volunteers was 3.4 +/− 6.3 out of a maximum score of 100, with significant correlation between increasing age and higher (worse) LSDI score (r = 0.30, P = 0.0001). Of the patients with spinal deformity undergoing analysis, 301 subsequently underwent surgery and 392 were subsequently treated nonoperatively. Operative patients had significantly higher preoperative LSDI scores than both nonoperative patients and asymptomatic volunteers (29.9 vs. 17.3 vs. 3.4, P < 0.0001 for both). For patients with ASD, significant correlations were found between LSDI and SRS-22 Pain and Function subscales (r = −0.75 and −0.76, respectively; P < 0.0001 for both). Conclusion. LSDI scores are low among asymptomatic volunteers, although stiffness-related disability increases with increasing age. Patients with ASD report substantial stiffness-related disability even prior to surgical fusion. Stiffness-related disability correlates with pain- and function-related disability measures among patients with spinal deformity. Level of Evidence: 1

The Health Impact of Adult Cervical Deformity in Patients Presenting for Surgical Treatment: Comparison to United States Population Norms and Chronic Disease States Based on the EuroQuol-5 Dimensions Questionnaire

BACKGROUND: Although adult cervical spine deformity (ACSD) is associated with pain and disability, its health impact has not been quantified in comparison to other chronic diseases. OBJECTIVE: To perform a comparative analysis of the health impact of symptomatic ACSD to US normative and chronic disease values using EQ‐5D (EuroQuol‐5 Dimensions questionnaire) scores. METHODS: ACSD patients presenting for surgical treatment were identified from a prospectively collected multicenter database. Baseline demographics and EQ‐5D scores were collected and compared with US normative and disease state values. RESULTS: Of 121 ACSD patients, 115 (95%) completed the EQ‐5D (60% women, mean age 61 years, previous spine surgery in 44%). Diagnoses included kyphosis with mid‐cervical (63.4%), cervico‐thoracic (23.5%), or thoracic (8.7%) apex and primary coronal deformity (4.3%). The mean ACSD EQ‐5D index was 0.511 (standard definition = 0.224), which is 34% below the bottom 25th percentile (0.780) for similar age‐ and gender‐matched US normative populations. Mean ACSD EQ‐5D index values were worse than the bottom 25th percentile for several other disease states, including chronic ischemic heart disease (0.708), malignant breast cancer (0.708), and malignant prostate cancer (0.708). ACSD mean index values were comparable to the bottom 25th percentile values for blindness/low vision (0.543), emphysema (0.508), renal failure (0.506), and stroke (0.463). EQ‐5D scores did not significantly differ based on cervical deformity type (P = .66). CONCLUSION: The health impact of symptomatic ACSD is substantial, with negative impact across all EQ‐5D domains. The mean ACSD EQ‐5D index was comparable to the bottom 25th percentile values for blindness/low vision, emphysema, renal failure, and stroke.