Faculty Bibliography

STUDY DESIGN:Retrospective review of KID Inpatient Database (KID) from 2003, 2006, 2009, and 2012. OBJECTIVES:The aim of this study was to evaluate the impact of advances in spinal surgery on patient outcomes in the treatment of Scheuermann kyphosis (SK). SUMMARY OF BACKGROUND DATA:SK is one of the most common causes of back pain in adolescents. Trends in diagnoses and surgical treatment and approach to SK have not been well described. METHODS:SK patients aged 0-20 years in KID were identified by ICD-9 code 732.0. KID-supplied year- and hospital-trend weights were used to establish prevalence. Patient demographics, surgical details, and outcomes were analyzed with analysis of variance. RESULTS:A total of 1,070 SK patients were identified (33.2% female), with increasing incidence of SK diagnosed from 2003 to 2012 (3.6-7.5 per 100,000, p < .001). The average age of operative patients was 16.1±2.0 years and did not change (16.27-16.06 years, p = .905). The surgical rate has not changed over time (72.8%-72.8%, p = .909). Overall, 96.3% of operative patients underwent fusion, with 82.2% of cases spanning ≥4 levels; in addition, 8.6% underwent an anterior-only surgery, 74.6% posterior-only, and 13.6% combined approach. From 2003 to 2012, rates of posterior-only surgeries increased (62.4%-84.4%, p < .001) whereas the rate of combined-approach surgeries decreased (37.6%-8.8%, p < .001). Overall complication rates for SK surgeries have decreased (2003: 20.9%; 2012: 11.9%, p = .029). Concurrently, the rate of ≥4-level fusions has increased (43.5%-89.6%, p < .001), as well as the use of Smith-Peterson (7.8%-23.6%, p < .001) and three-column osteotomies (0.0%-2.7%, p = .011). In subanalysis comparing posterior to combined approaches, complication rates were significantly different (posterior: 9.88%, combined: 19.46%, p = .005). Patients undergoing a combined approach have a longer length of stay (LOS) than patients undergoing a posterior-only approach (7.8 vs. 5.6 days, p < .001). CONCLUSIONS:Despite unchanged demographics and operative rates in SK, there has been a shift from combined to isolated posterior approaches, with a concurrent increase in levels treated. A combined approach was associated with increased complication rates, LOS, and total charges compared to isolated approaches. Awareness of these inherent differences is important for surgical decision making and patient education. LEVELS OF EVIDENCE:Level III.

OBJECTIVE:Neck and back pain are highly prevalent conditions that account for major disability. The Neck Disability Index (NDI) and Oswestry Disability Index (ODI) are the two most common functional status measures for neck and back pain. However, no single instrument exists to evaluate patients with concurrent neck and back pain. The recently developed Total Disability Index (TDI) combines overlapping elements from the ODI and NDI with the unique items from each. This study aimed to prospectively validate the TDI in patients with spinal deformity, back pain, and/or neck pain. METHODS:This study is a retrospective review of prospectively collected data from a single center. The 14-item TDI, derived from ODI and NDI domains, was administered to consecutive patients presenting to a spine practice. Patients were assessed using the ODI, NDI, and EQ-5D. Validation of internal consistency, test-retest reproducibility, and validity of reconstructed NDI and ODI scores derived from TDI were assessed. RESULTS:A total of 252 patients (mean age 55 years, 56% female) completed initial assessments (back pain, n = 115; neck pain, n = 52; back and neck pain, n = 55; spinal deformity, n = 55; and no pain/deformity, n = 29). Of these patients, 155 completed retests within 14 days. Patients represented a wide range of disability (mean ODI score: 36.3 ± 21.6; NDI score: 30.8 ± 21.8; and TDI score: 34.1 ± 20.0). TDI demonstrated excellent internal consistency (Cronbach's alpha = 0.922) and test-retest reliability (intraclass correlation coefficient = 0.96). Differences between actual and reconstructed scores were not clinically significant. Subanalyses demonstrated TDI's ability to quantify the degree of disability due to back or neck pain in patients complaining of pain in both regions. CONCLUSIONS:The TDI is a valid and reliable disability measure in patients with back and/or neck pain and can capture each spine region's contribution to total disability. The TDI could be a valuable method for total spine assessment in a clinical setting, and its completion is less time consuming than that for both the ODI and NDI.

Background/UNASSIGNED:A variety of techniques have been utilized to improve the accuracy of pedicle screw instrumentation. Recently, a novel handheld computerized drill system, IntelliSense Drill Technology, has been used in orthopedic trauma to improve drilling accuracy and reduce radiation and iatrogenic injury. The specialized drill technology detects changes in cortical density to prevent inadvertent cortical violation. The aim of this study is to assess the ability of this system to identify pedicle trajectories in the thoracic and lumbar spine compared to a standard freehand technique. Methods/UNASSIGNED:Two spine surgeons, including 1 senior-level and 1 junior-level attending drilled pedicle screw tracts using a freehand technique and computerized drill technology in 4 cadaveric spines from T2 to S1. A total of 134 pedicle screws were placed, including 70 by the senior surgeon and 64 by the junior surgeon. Cortical violations were assessed using computed tomography after instrumenting each pedicle tract, and procedure time for insertion of pedicle screws was recorded. Results/UNASSIGNED: = .063). Conclusions/UNASSIGNED:We demonstrate the use of a novel drill technology for placement of pedicle screws in the thoracic and lumbar spine. After an initial learning curve, this technology is comparable to use of a freehand technique by both a senior-level and a junior-level attending surgeon in a cadaveric model. Further investigation is needed to identify the clinical role of this technology in spine surgery.

Study Design/UNASSIGNED:Retrospective study of consecutive patients at a single institution.Objective: Examine the effect of minimally invasive surgery (MIS) versus open transforaminal lumbar interbody fusion (TLIF) surgery on long-term postoperative narcotic consumption. Objective/UNASSIGNED:Examine the effect of minimally invasive versus open TLIF on short-term postoperative narcotic consumption. Methods/UNASSIGNED:Differences between MIS and open TLIF, including inpatient opioid and nonopioid analgesic use, discharge opioid use, and postdischarge duration of narcotic usage were compared using appropriate statistical methods. Results/UNASSIGNED:= .018) compared with MIS TLIF. Conclusion/UNASSIGNED:Patients undergoing MIS TLIF required less inpatient opioids and had a decreased incidence of opioid dependence at 3-month follow-up. Patients with preoperative opioid use undergoing MIS TLIF are less likely to require long-term opioids.

BACKGROUND CONTEXT: Antifibrinolytic agents are used during ASD surgery to minimize blood loss and transfusion requirements. Tranexamic acid (TXA) reduces the risk of blood loss and transfusion after ASD surgery, but there persists concern for prothrombotic effects, myocardial infarction, stroke, and postoperative neurologic events including seizures. PURPOSE: To investigate perioperative blood loss and transfusion after TXA for ASD surgery. STUDY DESIGN/SETTING: Retrospective review of prospectively collected single center database. PATIENT SAMPLE: 469 patients who received TXA, and 354 patients who did not receive TXA. OUTCOME MEASURES: Perioperative blood loss and blood product transfusion rate, and complications.
METHOD(S): Using a single-institution multi-surgeon database, we performed a retrospective review of patients undergoing ASD surgery from 2011-2018. We identified 469 patients who received TXA, and 354 patients who did not receive TXA. We investigated perioperative blood loss and blood product transfusion rate, and complications occurring after surgery.
RESULT(S): There was no significant difference in age, BMI, or frailty between the TXA (age: 45 +/- 23, BMI: 25 +/- 6) and non-TXA group (age: 47 +/- 24, BMI: 26 +/- 7). The prevalence of coronary artery disease, chronic kidney disease, and history of pulmonary embolism was higher in the non-TXA group, presumably due to surgeon preoperative screening, with no difference in other medical comorbidities. There were more revision surgeries and pelvic fixation procedures in the TXA group, with no other differences in surgical complexity. The group that received TXA had significantly lower EBL (1693 +/- 1343 mL vs 2009 +/- 1892 mL, p=0.019), and were transfused less platelets intraoperatively (.07 +/-.3 U vs 0.25 +/- 0.86 U, p=0.012). There was no difference in rates of perioperative pRBC transfusion between the groups. The most common complications in both groups were ileus and urinary retention. There was no difference in rate of thrombotic, cardiac, or renal complications, or seizures between the two groups. There was no significant difference in 90-day complication, readmission, or revision rates.
CONCLUSION(S): Among patients undergoing ASD surgery, TXA was associated with a lower estimated blood loss, without a higher risk for any morbid event. To our knowledge, this is the largest study to date to evaluate the safety of TXA for ASD surgery. FDA DEVICE/DRUG STATUS: Unavailable from authors at time of publication.
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BACKGROUND CONTEXT: Sagittal malalignment has been discussed extensively in adult spinal deformity (ASD) literature, while coronal malalignment (CM) and fractional curve (FC) have received less attention. As a result, little guidance currently exists for surgical indications in managing CM, despite it being a relatively common occurrence that can considerably impact patient wellbeing. Patients with CM significantly affected by FC are at particular risk for continued CM postoperatively, along with its complications. PURPOSE: Assess types of approach to fusion of the fractional curve in ASD surgery and their relation to coronal alignment and sagittal alignment. STUDY DESIGN/SETTING: Retrospective review at single institution. PATIENT SAMPLE: A total of 82 ASD patients undergoing primary spinal fusion of 4 or more levels to sacrum or pelvis. OUTCOME MEASURES: Baseline (BL), 1-year (Y1) postoperatively and BL-Y1 difference (DELTABL-Y1) in magnitudes of FC, coronal alignment (CA) and sagittal alignment (SA) parameters: pelvic incidence-LL (PI-LL), cervical sagittal vertical axis (cSVA), T1 pelvic angle (TPA).
METHOD(S): Patients >=18 years old undergoing primary >=4-level fusion to sacrum/pelvis between October 2011 and January 2018 with minimum 6-month follow-up included. Chart review performed for operative dates and details and patient follow-up information. Coronal and sagittal parameters measured using deformity measuring software program. FC measured as segmental angle between L4 and S1. CA measured as distance between C7 plumb line and central sacral vertical line. CA>=20mm designated as CM, per guidelines in literature. Chi-squared test used to compare percentages and ANOVA used to compare means, with significance set at p<0.05.
RESULT(S): A total of 82 patients studied (68.3%F, age 62.6+/-13.3, BMI 28.1+/-6.6, Charlson comorbidity index 0.80+/-1.16). Nine patients (10.98%) had anterior-posterior fusion (AP), 41 (50%) posterior-only fusion with interbody device (PIB), 32 (39.02%) PSF without interbody (PSF). Twenty-three patients (28.04%) had FC>=15degree at BL, 7 (8.54%) at Y1. Forty-one patients (50%) had CM at BL, 35 (42.68%) at Y1. AP fusion patients had least levels fused (6.4 AP, 11.4 PIB, 11.8 PSF, p<0.001). No difference in revision by approach (55.56% AP, 24.39% PIB, 28.13% PSF, p=0.179). Approach type was not associated with different BL, Y1 or DELTABL-Y1 alignment parameters for FC, CA or SA. Mean FC 9.89degree at BL, 6.91degree at Y1 and DELTABL-Y1 difference 5.77degree, no difference between approach groups (p=0.361, 0.127, 0.550, respectively). Mean value for CA 33.62mm at BL, 21.15mm at Y1 and DELTABL-Y1 difference 23.23mm, no difference between approach groups (p=0.087, 0.153, 0.206, respectively). Mean PI-LL 25.21degree at BL, 11.1degree at Y1 and DELTABL-Y1 difference -13.7degree, no difference between approach groups (p=0.503, 0.600, 0.356, respectively). Mean cSVA 27.53degree at BL, 28.85degree at Y1 and DELTABL-Y1 difference 1.29degree, no difference between approach groups (p=0.364, 0.099, 0.141, respectively). Mean TPA 28.37degree at BL, 21.12degree at Y1 and DELTABL-Y1 difference -6.63degree, no difference between approach groups (p=0.066, 0.248, 0.138, respectively).
CONCLUSION(S): Fusion to the sacrum/pelvis improves sagittal alignment, fractional curve and coronal alignment in most patients. However, while fractional curve and sagittal alignment are better corrected, coronal malalignment, particularly more severe malalignment at baseline, tends to persist postoperatively. Type of approach and use of interbody device does not appear to significantly impact these results. This should be considered in preoperative planning for patients with coronal deformity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Surgical correction of adolescent idiopathic scoliosis is advocated for severe curves to preserve or improve pulmonary function, prevent progressive deformity and pain, and improve self-appearance. Restoration of sagittal and 3D alignment, in particular thoracic kyphosis (TK), has become increasingly emphasized in efforts to improve pulmonary function, thoracic volumes, provide improved sagittal balance, and prevent adjacent segment degeneration and deformity. PURPOSE: To study the effects of thoracic kyphosis restoration in AIS type 1 and 2 curves on postoperative thoracic volume and pulmonary function. STUDY DESIGN/SETTING: Retrospective review of prospective multicenter database. PATIENT SAMPLE: Thirty-nine AIS patients with Type 1 and 2 curves with 5Y postoperative stereo-radiographic data and pulmonary function tests (PFTs). OUTCOME MEASURES: Five-year spinal and rib cage measures and PFTs.
METHOD(S): A multicenter prospective registry of patients undergoing surgical correction of Type 1- and 2- AIS curves was queried for patients with 5-year postoperative visits including stereoradiographic assessment and PFTs. 3-dimensional (3D) radiographic analysis was performed to assess spinal alignment and chest wall dimensions at preoperative, first erect and 5 year postoperative time points. Variables were analyzed between time points with a one-way ANOVA and post-hoc Tukey analysis, and between variables with linear regression analysis.
RESULT(S): A total of 39 patients met the inclusion criteria (37F, age 14.4+/-2.2). 3D spine alignment analyses demonstrated significant reduction in pre-op to 1st erect upper thoracic (41.3degree to 11.6degree), mid-thoracic (48.6degree to 9.55degree) and lumbar Cobb angles (19.7degree to 8.9degree), an increase in TK:T2-12 (20.0degree to 39.8degree) and TK:T5-12 (9.8 to 28.2degree), and reduction in proximal and mid-thoracic apical vertebral rotation (9.5degree to 2.1degree) from preoperative to 1st erect postoperative (p<0.001 for all). 3D spinal alignment remained stable from 1st erect to 5 years (p>0.05 for all). 3D rib cage analysis demonstrated there was a small reduction in maximal depth (144 mm to 138 mm), maximum width (235 mm to 232 mm), and increase in thoracic height (220 mm to 230 mm, p<0.01 for all), but no significant change in rib cage volume (5136 to 5202 cm³ p=0.184). There was no correlation between change in coronal or sagittal alignment parameters and perioperative change in rib cage volume. From first erect to 5-year a significant increase in max depth (138 mm to 144 mm), width (232 mm to 242 mm), thoracic height (230 mm to 233 mm) and rib cage volume (5202 cm to 5912 cm, p<0.001 for all) occurred. Pulmonary function analysis showed significant improvement in FEV1 (2.73 to 2.98 L, p=0.003) and FVC (3.22 to 3.46 L, p=0.006) from preoperative to 5-year, however, TLC did not change (4.54 to 4.59 L, p=0.517). Percent predicted TLC was reduced (Pre:101.3% to 5Y:89.1%, p<0.001), however, % predicted FEV and FVC did not (89% to 86.4%, p=0.227 & 92.5% to 87.7%, p=0.10 respectively). PFTs at 5-year follow-up correlated most closely with rib cage volume at 5-year follow-up (FEV r=0.643, FVC r=0.800, TLC r=0.73, p<0.001).
CONCLUSION(S): While thoracic kyphosis increases, coronal Cobb and apical vertebral rotation decrease postoperatively, these do not directly influence chest wall volume. Chest wall volume continues to increase between from first erect to 5 years due to presumed growth, which corresponds with an improvement in FEV1 and FVC at 5 year follow-up. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Cerebral palsy (CP) can be described as a "static encephalopathy with progressive musculoskeletal pathology." Nonambulant children (GMFCS IV&V) have high rates of both spastic hip disease and neuromuscular scoliosis. Adult sagittal spinal deformity correction is known to cause acetabular retroversion and reduced pelvic tilt, resulting in increased rates of prosthetic hip dislocation; however, the role of spinal alignment on hip status in CP remains unknown. PURPOSE: To identify surgical factors and postoperative spinal alignment parameters that are associated with worsening postoperative hip status (WHS) (ie, subluxation, dislocation or resection) after spinal fusion. STUDY DESIGN/SETTING: Prospective multicenter outcomes study of nonambulant CP patients (GMFCS IV&V) requiring spinal fusion. PATIENT SAMPLE: A total of 142 operative CP patients with preoperative, 6-week, 1Y, 2Y and 5Y postoperative follow-up. OUTCOME MEASURES: Postoperative spinal alignment parameters associations with WHS up to 5Y postoperatively.
METHOD(S): WHS was defined by permutations of baseline and 1Y, 2Y and 5Y hip status of left and right hips by a change from either a normal hip at baseline (BL) that became subluxated, dislocated or resected at postop intervals; or if a subluxated hip at BL became dislocated or resected at postop intervals. Hip status up to 5Y postop was analyzed according to age, sex, coronal spinal alignment (major curve Cobb, pelvic obliquity), sagittal spinal alignment (thoracic kyphosis, T12-S1 lumbar lordosis, C7-S1 sagittal vertical axis), Risser score, hip position at rest, upper and lower- instrumented vertebrae (UIV&LIV), levels fused and fusion to the sacrum. Potential cutoff values for alignment parameters at which the relationship with hip status was determined using receiver operating characteristic (ROC) curves. Logistic regression was used to determine odds ratios for predictors of WHS.
RESULT(S): Of 142 patients (mean age 13.7+/-2.5, 48.3% female), 36 (25.4%) had WHS postoperatively. 7 had reoperation of their spinal fusion, 3 for loose screws/bolts and 4 for prominent instrumentation. ROC curve analysis and multivariate logistic regression demonstrated that the only spino-pelvic alignment parameter that significantly correlated with WHS was lumbar hyperlordosis (T12-L5) >60degree (p=.015), OR=2.61 (CI 1.19-5.75). Assessment of all patients demonstrated an increase in pre- to postop LL. Change in LL pre- to postoperative was no different between groups (p=.643), however the WHS group was more lordotic at baseline and postop (pre 44degree, post 58degree) compared to the no change group (pre 36degree, post 50degree). Age at surgery (p=0.214), sex (p=0.955), Risser score (p=0.205), major coronal cobb angle (p=0.907), thoracic kyphosis (p=0.717), global sagittal alignment (C7-S1 SVA p=0.320), levels fused (p=0.064), fusion to the sacrum (p=.548), coronal pelvic obliquity (p=0.652), or hip position at rest (adducted/abducted/neutral; p=.284) were not associated with WHS. Reoperation was not associated with WHS (p=.304).
CONCLUSION(S): Postoperative hyperlordosis (>60degree) is the only determined risk for WHS at 5Y after spinal fusion in nonambulant patients with cerebral palsy (GMFCS IV&V). WHS likely relates to anterior pelvic tilt and functional acetabular retroversion due to hyperlordosis, as well as loss of protective lumbo-pelvic motion causing anterior femoracetabular impingement. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Although the health impact of adult symptomatic lumbar scoliosis (ASLS) is substantial, these patients often have other orthopedic disease burden that may further negatively impact their health-related quality of life (HRQL) and recovery following ASLS treatment. This additional disease burden has not been well quantified in the ASLS population. PURPOSE: To assess nonthoracolumbar orthopedic (NTO) disease burden in ASLS patients enrolled in a prospective multicenter study. STUDY DESIGN/SETTING: Retrospective review of prospective multicenter cohort. PATIENT SAMPLE: Patients enrolled in the ASLS prospective multicenter study of operative vs nonoperative treatment. OUTCOME MEASURES: Occurrence of non-thoracolumbar orthopedic events, Scoliosis Research Society-22r (SRS-22), Oswestry Disability Index (ODI), SF-12 physical component summary (PCS).
METHOD(S): The ASLS study is a prospective multicenter study to assess operative vs nonoperative treatment for ASLS, with randomized and observational arms. Patients recruited were 40-80 years old with ASLS, defined as a lumbar coronal Cobb >30degree and ODI >20 or SRS-22 <4.0 in pain, function and/or self-image domains. Incidence of NTO disease burden was assessed in the overall study population from enrollment up to 4-yr follow-up, with comparisons between as-treated operative and nonoperative patients combining randomized and observational cohorts. NTO events for this study only included orthopedic conditions requiring surgical treatment and fractures.
RESULT(S): Two hundred eighty-six patients (mean age 60 yrs, 90% women) were enrolled, with as-treated cohorts of 173 operative and 113 nonoperative patients, and 4-yr follow-up rate of 81%. At a mean follow-up of 3.8 yrs (SD=0.9 yrs), 108 NTO events were reported, affecting 71 (24.8%) patients. The most common NTO events included: arthroplasty (n=39), fractures (n=26), joint ligament/cartilage repair (n=13), cervical surgery (n=7), and carpal tunnel release (n=5). Patients with an NTO event were significantly older (63 vs 59 yrs, p<0.001), more likely to have any history of smoking (50.7% vs 32.1%, p=0.007), had worse baseline deformity based on SRS-Schwab PI-LL (p=0.002) and PT (p=0.012) modifiers, and had worse baseline function (SF-12 PCS, p=0.009). Patients with and without an NTO event did not differ based on ASLS operative vs nonoperative treatment (p=0.405), gender (p=0.491), BMI (p=0.441), or femoral neck t score (p=0.512). Patients undergoing an arthroplasty following study enrollment were not older (p=0.09) but were more likely to have any history of smoking (15.2% vs 7.2%, p=0.041), had worse baseline deformity based on SRS-Schwab PI-LL modifier (p=0.002), and had worse baseline pain (SRS-22 pain, p=0.017) and function (ODI, p=0.003).
CONCLUSION(S): ASLS patient have a high NTO disease burden, with almost 25% of patients in this prospective multicenter study having an orthopedic condition requiring surgical treatment or a fracture within 3.8 yrs following study enrollment. Patients with an NTO event were more likely to have any history of smoking and had worse baseline spinal deformity and disability. These conditions may further impact HRQL and recovery following ASLS treatment. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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