Role of Topical Tranexamic Acid on Blood Loss and Transfusion Requirements in Spinal Fusion for Neuromuscular and Syndromic Scoliosis.

STUDY DESIGN: Retrospective case control study. OBJECTIVES: To determine the role of TXA when used as topical soaked sponges (tTXA) on peri-operative blood loss and changes in hemoglobin following posterior spinal fusion (PSF) for neuromuscular and syndromic scoliosis (NMS). METHODS: A single center review of NMS patients who underwent PSF was conducted. The initial set of patients where no tTXA (control) was used were compared to consecutive NMS patients in whom tTXA was used. In the tTXA group, sponges soaked in 1g TXA in 500 mL normal saline were packed in the wound instead of dry sponges. Estimated blood loss (EBL) was calculated intraoperatively using a standard way. Pre-operative, intra-operative and immediate post-operative variables were collected and compared between the 2 groups. RESULTS: 33 patients were included (mean age- 13.5 yrs., BMI- 21, 17 patients in tTXA and 16 patients in control group). Pre-op demographic and radiographic variables were similar between the 2 groups. EBL, EBL per level, EBVL, operative time and number of levels fused were similar in both groups. tTXA group received less intra-operative pRBC transfusion as compared to the control group (150 ± 214 vs 363 ± 186 cc, P = .004). No difference was noted in post-op blood transfusion and drain output for 3 days in both the groups. tTXA group had lesser hospital (5.1 vs 8.9 days) and ICU length of stay (2 vs 4.2 days) and fewer immediate post-operative complications (23.5 vs 52.9%) compared to the control group but not statistically significant (P > .05). CONCLUSION: Administration of tTXA-soaked sponges is an effective and safe method to reduce intraoperative blood transfusion requirements in the correction of spinal deformity in patients with NMS.

Is there an anatomic basis for the different behavior of Lenke types 1AR and 1AL in idiopathic scoliosis? A study on facet joint tropism influence.

INTRODUCTION: AIS type 1 Curves are sub-classified based on the tilt of L4 as 1AR and 1AL. These curves are different w.r.t their curve behavior, progression and level selection. Presently there is no known anatomic etiology for the different behavior. Facet tropism (FT) is defined as the asymmetry between the facet angle of the left and right facet joints. The purpose of this study was to evaluate the correlation between facet tropism in the lumbar segments and occurrence of type 1AR and 1AL curves in AIS patients. METHODS: AIS patients with diagnosis of type 1 AR and 1AL right thoracic AIS curves who underwent posterior instrumented fusion were queried from a single institutions' database. Patients needed to have an MRI of their entire spine to be included. L2-3, L3-4 and L4-5 Facet angles (FA, angle made by the facet line with the mid-sagittal line at respected vertebral level) were calculated. FT was classified as follows: ≤ 5° (minimal), 6- 10° (mild) and ≥ 11° (severe). 1AR and 1AL curves were compared for FA, FT and FT grade at each lumbar segmental levels. RESULTS: One hundred nineteen patients were included (77 females, mean age-13.85 years, mean BMI- 21.63, 73 1AL and 46 1AR). The mean thoracic Cobb was 52.5 ± 9.8°, thoracic kyphosis was 28.12 ± 12° and lumbar lordosis was 53.48 ± 12.6°. L3-4 FA on the right side was more coronally oriented in 1AR curves compared to 1AL curves (37° vs. 31°, p = 0.04). On comparing FT at each level, 1AR curves had a higher FT at L3-4 (1.5° vs. - 2.3°, p = 0.01) and L4-5 levels (5.8° vs. - 0.28°, p < 0.001) compared to 1AL patients. Similarly, 1AR patients had significantly more patients with severe FT at L3-4 (34.8% vs. 13.7%, p = 0.02) and at L4-5 (17.3% vs. 6.8%, p = 0.01) compared to 1ALcurves. CONCLUSION: L3-4 joints are more coronally oriented in 1AR curves compared to 1AL curves. 1AR patients displayed higher FT at L3-4 and L4-5 compared to 1AL patients. 1AR curves also reveal a higher percentage of severe FT at L3-4 and L4-5 levels. This may influence the curve behavior and progression in these two curve types.

Utilization of pre-operative MRI to identify AIS patients at highest risk of intra-operative neuromonitoring alert.

PURPOSE: Utility of pre-operative MRI for patients undergoing scoliosis correction has expanded to include an MRI classification for identifying patients at increased risk of experiencing intra-operative neuromonitoring (IONM) alerts based on the shape of the spinal cord and circumferential presence of CSF at the apex of the thoracic curve. In the present study, the authors explore the utility of this new MRI classification and multiple X-ray radiographic parameters in identifying the AIS sub-population at high risk of IONM alerts. METHODS: AIS patients < 18 years old who underwent posterior spinal fusion between 2018 and 2022 at a single institution. Imaging reviewed to determine main thoracic (MT) and thoraco-lumbar (TL) Cobb angles, major thoracic Apical Vertebral Translation (AVT) and lumbar/thoraco-lumbar AVT (TL AVT), thoracic kyphosis (TK), coronal main thoracic Deformity Angular Ratio (cDAR), sagittal DAR (sDAR), and MRI to determine the spinal cord type (1, 2, or 3). RESULTS: A total of 155 AIS patients who met the inclusion criteria between 2018 and 2022 were included. There was a trend to have an increased incidence of Type 3 spinal cord shape both with increase in the MT Cobb angle and MT AVT. There was also a shift toward more IONM alerts in patients with Type 3 (19.5%) spinal cords, AVT ≥ 5 cm (18.9%), and Cobb angle ≥ 650 (28.2%). CONCLUSION: Higher magnitude of thoracic Cobb angle and AVT are associated with higher likelihood of type 3 spinal cord at the apex in MRI. Patients with Type 3 spinal cord, Cobb angle ≥ 650, AVT > 5 cm, and cDAR > 10 have higher likelihood to have IONM alerts. Patient with a Type 3 spinal cord and a Cobb angle ≥ 650 (50.0%), cDAR > 10 (43.7%), and AVT > 5 cm (35.2%) have the highest risk of having IONM alerts.

The Approach to Pseudarthrosis After Adult Spinal Deformity Surgery: Is a Multiple-Rod Construct Necessary?

STUDY DESIGN: Retrospective study. OBJECTIVES: Our goal was to evaluate the rate of rod fracture and persistent pseudarthrosis in cohorts of patients treated with a dual rod or multiple-rod construct in revision surgery for pseudarthrosis. METHODS: A dual rod construct was used in 23 patients, and a multiple rod construct in 24 patients, spanning the pseudarthrosis level. Two-year fusion grading, and rates of pseudarthrosis and implant failure, were assessed. RESULTS: There were no differences in patient or surgical characteristics between the groups: (2- rod construct: Age 60 ± 14, Levels 10 ± 5, 3-column osteotomy:17%; multiple-rod construct: Age: 62 ± 11, Levels 9 ± 4, 3-column osteotomy:30%). Patients in the multiple rod construct were transfused a greater volume of packed red blood cells (pRBCs) intraoperatively (2.6 ± 2.9 vs. 1.1 ± 1.5 U, p < 0.0001). At 2 year follow up there was no difference in fusion grades at the previous level of pseudarthrosis, the rate of rod fracture or pseudarthrosis between the 2 groups, or rate of reoperation for pseudarthrosis, rod fracture, wound infection, hardware prominence, or PJK/PJF. CONCLUSIONS: Our data demonstrate no difference in fusion grade, or rates of rod fracture and revision at 2 years, after utilizing a dual rod versus multiple rod construct in revision surgery for pseudarthrosis. The low complication rates seen with either configuration warrant further investigation of the optimal instrumentation configuration.

Case Start Timing of Adult Spinal Deformity Surgeries: Does the Wait Matter?

BACKGROUND: Adult spinal deformity (ASD) surgery can entail complex reconstructive procedures. It is unclear whether there is any effect of case start time on outcomes. We sought to evaluate the effects of case start time and day of the week on 90-day complication, readmission, and revision rates after ASD surgery. METHODS: This is a retrospective study of 1040 ASD patients from a single institution. We collected start times and day of the week for cases from 2011 to 2018. Early start was designated as any case starting either before or at 7:30 am or between 7:30 and 11 am; late start was designated as any case starting at 11 am or later. Outcome measures include 90-day complication, revision, and readmission rates. RESULTS: A total of 1040 ASD patients (age, 46 ± 23 years; body mass index, 25 ± 7; American Society of Anesthesiologists classification, 2.5 ± 0.6; levels fused, 10 ± 4; three column osteotomy (3CO), 13%) were included. There was no association between surgery day of the week and length of stay, 90-day complication, readmission, or reoperation rates in the adjusted analyses. Late start cases had higher rates of 90-day readmission (10.5% vs 6.0%, P = 0.02), reoperation (11.9% vs 6.6%, P = 0.008), and neurologic injury (5.2% vs 2.1%, P = 0.019). Subanalysis of neurologic complications demonstrated that there was a higher rate of postoperative radiculopathy (P = 0.007) and residual central or foraminal stenosis (P = 0.029) in late start cases. A late start time was predictive of increased risk for 90-day readmission (OR 1.8, P = 0.02), unplanned reoperation (OR 1.9, P = 0.009), and neurologic complication (OR 2.1, P = 0.046). CONCLUSIONS: A late OR start time was predictive of increased risk for neurologic complication, 90-day readmission, and unplanned reoperation. The well-established protocols for first start OR times for elective ASD surgery may decrease outcome risk and reduce variability in complication rates. CLINICAL RELEVANCE: Understanding the impact of start time on outcomes and complications after ASD surgery is helpful for surgeons in preoperative planning and for institutions and hospitals' allocation of operating room staff and resources.

Impact of Supine Radiographs to Assess Curve Flexibility in the Treatment of Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The purpose of the study is to evaluate the role of supine radiographs in determining flexibility of thoracic and thoracolumbar curves. METHODS: Ninety operative AIS patients with 2-year follow-up from a single institution were queried and classified into MT structural and TL structural groups. Equations were derived using linear regression to compute cut-off values for MT and TL curves. Thresholds were externally validated in a separate database of 60 AIS patients, and positive and negative predictive values were determined for each curve. RESULTS: MT supine values were highly predictive of MT side-bending values (TL group: 0.63, P < 0.001; MT group: 0.66, P = 0.006). Similarly, TL supine values were highly predictive of TL side-bending values (TL group: 0.56, P = 0.001 MT group: 0.68, P = 0.001). From our derived equations, MT and TL curves were considered structural on supine films if they were ≥ 30° and 35°, respectively. Contingency table analysis of external validity sample showed that supine films were highly predictive of structurality of MT curve (Sensitivity = 0.91, PPV = 0.95, NPV = 0.81) and TL curve (Sensitivity = 0.77, PPV = 0.81, NPV = 0.94). ROC analysis revealed that the area under curve for MT structurality from supine films was 0.931 (SEM: 0.03, CI: 0.86-0.99, P < 0.001) and TL structurality from supine films was 0.922 (SEM: 0.03, CI- 0.84-0.98, P < 0.001). CONCLUSIONS: A single preoperative supine radiograph is highly predictive of side-bending radiographs to assess curve flexibility in AIS. A cut-off of ≥ 30° for MT and ≥ 35° for TL curves in supine radiographs can determine curve structurality.

Pseudarthrosis and Rod Fracture Rates After Transforaminal Lumbar Interbody Fusion at the Caudal Levels of Long Constructs for Adult Spinal Deformity Surgery.

BACKGROUND: Interbody fusion at the caudal levels of long constructs for adult spinal deformity (ASD) surgery is used to promote fusion and secure a solid foundation for maintenance of deformity correction. We sought to evaluate long-term pseudarthrosis, rod fracture, and revision rates for TLIF performed at the base of a long construct for ASD. METHODS: We reviewed 316 patients who underwent TLIF as a component of ASD surgery for medical comorbidities, surgical characteristics, and rate of unplanned reoperation for pseudarthrosis or instrumentation failure at the TLIF level. Fusion grading was assessed after revision surgery for pseudarthrosis at the TLIF level. RESULTS: Rate of pseudarthrosis at the TLIF level was 9.8% (31/316), and rate of rod fractures was 7.9% (25/316). The rate of revision surgery at the TLIF level was 8.9% (28/316), and surgery was performed at a mean of 20.4 ± 16 months from the index procedure. Current smoking status (odds ratio 3.34, P = 0.037) was predictive of pseudarthrosis at the TLIF site. At a mean follow-up of 43 ± 12 months after revision surgery, all patients had achieved bony union at the TLIF site. CONCLUSIONS: At 3-year follow-up, the rate of pseudarthrosis after TLIF performed at the base of a long fusion for ASD was 9.8%, and the rate of revision surgery to address pseudarthrosis and/or rod fracture was 8.9%. All patients were successfully treated with revision interbody fusion or posterior augmentation of the fusion mass, without need for further revision procedures at the TLIF level.

Not Frail and Elderly: How Invasive Can We Go in This Different Type of Adult Spinal Deformity Patient?

STUDY DESIGN: Retrospective review of a single-center spine database. OBJECTIVE: Investigate the intersections of chronological age and physiological age via frailty to determine the influence of surgical invasiveness on patient outcomes. SUMMARY OF BACKGROUND DATA: Frailty is a well-established factor in preoperative risk stratification and prediction of postoperative outcomes. The surgical profile of operative patients with adult spinal deformity (ASD) who present as elderly and not frail (NF) has yet to be investigated. Our aim was to examine the surgical profile and outcomes of patients with ASD who were NF and elderly. METHODS: Patients with ASD 18 years or older, four or greater levels fused, with baseline (BL) and follow-up data were included. Patients were categorized by ASD frailty index: NF, Frail (F), severely frail (SF]. An elderly patient was defined as 70 years or older. Patients were grouped into NF/elderly and F/elderly. SRS-Schwab modifiers were assessed at BL and 1 year (0, +, ++). Logistic regression analysis assessed the relationship between increasing invasiveness, no reoperations, or major complications, and improvement in SRS-Schwab modifiers [Good Outcome]. Decision tree analysis assessed thresholds for an invasiveness risk/benefit cutoff point. RESULTS: A total of 598 patients with ASD included (55.3 yr, 59.7% F, 28.3 kg/m2). 29.8% of patients were older than 70 years. At BL, 51.3% of patients were NF, 37.5% F, and 11.2% SF. Sixty-sis (11%) patients were NF and elderly. About 24.2% of NF-elderly patients improved in SRS-Schwab by 1 year and had no reoperation or complication postoperatively. Binary regression analysis found a relationship between worsening SRS-Schwab, postop complication, and reoperation with invasiveness score (odds ratio: 1.056 [1.01-1.102], P = 0.011). Risk/benefit cut-off was 10 (P = 0.004). Patients below this threshold were 7.9 (2.2-28.4) times more likely to have a Good Outcome. 156 patients were elderly and F/SF with 16.7% having good outcome, with a risk/benefit cut-off point of less than 8 (4.4 [2.2-9.0], P < 0.001). CONCLUSION: Frailty status impacted the balance of surgical invasiveness relative to operative risk in an inverse manner, whereas the opposite was seen amongst elderly patients with a frailty status less than their chronologic age. Surgeons should perhaps consider incorporation of frailty status over age status when determining realignment plans in patients of advanced age.Level of Evidence: 3.

Clinical photographs in the assessment of adult spinal deformity: a comparison to radiographic parameters.

OBJECTIVE: The goal of this study was to reliably predict sagittal and coronal spinal alignment with clinical photographs by using markers placed at easily localized anatomical landmarks. METHODS: A consecutive series of patients with adult spinal deformity were enrolled from a single center. Full-length standing radiographs were obtained at the baseline visit. Clinical photographs were taken with reflective markers placed overlying C2, S1, the greater trochanter, and each posterior-superior iliac spine. Sagittal radiographic parameters were C2 pelvic angle (CPA), T1 pelvic angle (TPA), and pelvic tilt. Coronal radiographic parameters were pelvic obliquity and T1 coronal tilt. Linear regressions were performed to evaluate the relationship between radiographic parameters and their photographic "equivalents." The data were reanalyzed after stratifying the cohort into low-body mass index (BMI) (< 30) and high-BMI (≥ 30) groups. Interobserver and intraobserver reliability was assessed for clinical measures via intraclass correlation coefficients (ICCs). RESULTS: A total of 38 patients were enrolled (mean age 61 years, mean BMI 27.4 kg/m2, 63% female). All regression models were significant, but sagittal parameters were more closely correlated to photographic parameters than coronal measurements. TPA and CPA had the strongest associations with their photographic equivalents (both r2 = 0.59, p < 0.001). Radiographic and clinical parameters tended to be more strongly correlated in the low-BMI group. Clinical measures of TPA and CPA had high intraobserver reliability (all ICC > 0.99, p < 0.001) and interobserver reliability (both ICC > 0.99, p < 0.001). CONCLUSIONS: The photographic measures of spinal deformity developed in this study were highly correlated with their radiographic counterparts and had high inter- and intraobserver reliability. Clinical photography can not only reduce radiation exposure in patients with adult spinal deformity, but also be used to assess deformity when full-spine radiographs are unavailable.

Operative versus nonoperative treatment for adult symptomatic lumbar scoliosis at 5-year follow-up: durability of outcomes and impact of treatment-related serious adverse events.

OBJECTIVE: Although short-term adult symptomatic lumbar scoliosis (ASLS) studies favor operative over nonoperative treatment, longer outcomes are critical for assessment of treatment durability, especially for operative treatment, because the majority of implant failures and nonunions present between 2 and 5 years after surgery. The objectives of this study were to assess the durability of treatment outcomes for operative versus nonoperative treatment of ASLS, to report the rates and types of associated serious adverse events (SAEs), and to determine the potential impact of treatment-related SAEs on outcomes. METHODS: The ASLS-1 (Adult Symptomatic Lumbar Scoliosis-1) trial is an NIH-sponsored multicenter prospective study to assess operative versus nonoperative ASLS treatment. Patients were 40-80 years of age and had ASLS (Cobb angle ≥ 30° and Oswestry Disability Index [ODI] ≥ 20 or Scoliosis Research Society [SRS]-22 subscore ≤ 4.0 in the Pain, Function, and/or Self-Image domains). Patients receiving operative and nonoperative treatment were compared using as-treated analysis, and the impact of related SAEs was assessed. Primary outcome measures were ODI and SRS-22. RESULTS: The 286 patients with ASLS (107 with nonoperative treatment, 179 with operative treatment) had 2-year and 5-year follow-up rates of 90% (n = 256) and 74% (n = 211), respectively. At 5 years, compared with patients treated nonoperatively, those who underwent surgery had greater improvement in ODI (mean difference -15.2 [95% CI -18.7 to -11.7]) and SRS-22 subscore (mean difference 0.63 [95% CI 0.48-0.78]) (p < 0.001), with treatment effects (TEs) exceeding the minimum detectable measurement difference (MDMD) for ODI (7) and SRS-22 subscore (0.4). TEs at 5 years remained as favorable as 2-year TEs (ODI -13.9, SRS-22 0.52). For patients in the operative group, the incidence rates of treatment-related SAEs during the first 2 years and 2-5 years after surgery were 22.38 and 8.17 per 100 person-years, respectively. At 5 years, patients in the operative group who had 1 treatment-related SAE still had significantly greater improvement, with TEs (ODI -12.2, SRS-22 0.53; p < 0.001) exceeding the MDMD. Twelve patients who received surgery and who had 2 or more treatment-related SAEs had greater improvement than nonsurgically treated patients based on ODI (TE -8.34, p = 0.017) and SRS-22 (TE 0.32, p = 0.029), but the SRS-22 TE did not exceed the MDMD. CONCLUSIONS: The significantly greater improvement of operative versus nonoperative treatment for ASLS at 2 years was durably maintained at the 5-year follow-up. Patients in the operative cohort with a treatment-related SAE still had greater improvement than patients in the nonoperative cohort. These findings have important implications for patient counseling and future cost-effectiveness assessments.

The Ankle-Pelvic Angle (APA) and Global Lower Extremity Angle (GLA): Summary Measurements of Pelvic and Lower Extremity Compensation.

BACKGROUND: Adult sagittal spinal deformity (SSD) leads to the recruitment of compensatory mechanisms to maintain standing balance. After regional spinal compensation is exhausted, lower extremity compensation is recruited. Knee flexion, ankle flexion, and sacrofemoral angle increase to drive pelvic shift posterior and increase pelvic tilt. We aim to describe 2 summary angles termed ankle-pelvic angle (APA) and global lower extremity angle (GLA) that incorporate all aspects of lower extremity and pelvic compensation in a comprehensive measurement that can simplify radiographic analysis. METHODS: Full-body sagittal stereotactic radiographs were retrospectively collected and digitally analyzed. Spinal and lower extremity alignment were quantified with existing measures. Two angles-APA and GLA-were drawn as geometrically complementary angles to T1-pelvic angle (TPA) and global sagittal axis (GSA), respectively. Regression analysis was used to represent the predictive relationship between TPA and APA and between GSA and GLA. RESULTS: A total of 518 propensity score-matched patient records were available for analysis. Patients with lower extremity compensation had higher APA (21.83° versus 19.47°, P = .007) and GLA (6.03° versus 1.19°, P < .001) than those without compensation. APA and GLA demonstrated strong correlation with TPA (r = 0.81) and GSA (r = 0.77), respectively. Furthermore, the change between preoperative and postoperative values were strongly correlative between ΔAPA and ΔTPA (r = 0.71) and between ΔGLA and ΔGSA (r = 0.77). APA above 20.6° and GLA above 3.6° were indicative of lower extremity compensation. Patients with increased GLA values had significantly higher Oswestry Disability Index scores (48.67 versus 41.04, P = .005). CONCLUSIONS: TPA and GSA are measures of global spinal alignment and APA and GLA, respectively, and are geometrically complementary angles that vary proportionately to SSD and balance the body. APA and GLA increase in SSD patients with lower extremity compensation and decrease with corrective surgery. LEVEL OF EVIDENCE: 4. CLINICAL RELEVANCE: APA and GLA offer a concise and simple method of communicating pelvic and lower extremity compensation.

Complications After Adult Spinal Deformity Surgeries: All Are Not Created Equal.

BACKGROUND: Data on timing of complications are important for accurate quality assessments. We sought to better define pre- and postdischarge complications occurring within 90 days of adult spinal deformity (ASD) surgery and quantify the effect of multiple complications on recovery. METHODS: We performed a review of 1040 patients who underwent ASD surgery (age: 46 ± 23; body mass index: 25 ± 7, American Society of Anesthesiologists [ASA] score: 2.5 ± 0.6, levels: 10 ± 4, revision: 9%, 3-column osteotomy: 13%). We assessed pre- and postdischarge complications and risk factors for isolated versus multiple complications, as well as the impact of multiple complications. RESULTS: The 90-day complication rate was 17.7%. 85 patients (8.2%) developed a predischarge complication, most commonly ileus (12%), and pulmonary embolism (PE; 7.1%). The most common causes of predischarge unplanned reoperation were neurologic injury (12.9%) and surgical site drainage (8.2%). Predictors of a predischarge complication included smoking (odds ratio [OR]: 2.2, P = .02), higher ASA (OR: 1.8, P = .008), hypertension (HTN; OR: 2.0, P = .004), and iliac fixation (OR: 4.3, P < .001). Ninety-nine patients (9.5%) developed a postdischarge complication, most commonly infection (34%), instrumentation failure (13.4%), and proximal junctional failure (10.4%). Predictors of postdischarge complications included chronic obstructive pulmonary disease (OR: 3.6, P < .0001), congestive heart failure (OR: 4.4, P = .016), HTN (OR: 2.3, P < .0001), and multiple rod construct (OR: 1.8, P = .02). Patients who developed multiple complications (9.3%) had a longer length of stay, and increased risk for readmission and unplanned reoperation. CONCLUSIONS: Knowledge regarding timing of postoperative complications in relation to discharge may better inform quality improvement measures. PE and implant-related complications play a prominent role in perioperative complications and need for readmission, with several modifiable risk factors identified. LEVEL OF EVIDENCE: Level 3. CLINICAL RELEVANCE: Advances in surgical techniques and instrumentation have improved postoperative radiographic and clinical outcomes after ASD surgery. The rate of complications after complex ASD surgery remains high, both at early postoperative and long term follow-up. This study reviews complications within 90 days of surgery, with an assessment of patient and surgical risk factors. We found that modifiable risk factors for early complications after ASD surgery include COPD, and current smoking. The data presented in this study also provide surgeons with knowledge of the most common complications encountered after ASD surgery, to aid in preoperative patient discussion.

Topical tranexemic acid reduces intra-operative blood loss and transfusion requirements in spinal deformity correction in patients with adolescent idiopathic scoliosis.

PURPOSE: To evaluate the effectiveness of the use of topical tranexamic acid (tTXA) in spinal deformity correction in AIS patients METHODS: Sixty consecutive operative AIS patients were reviewed from a single institution and divided into two groups with similar demographics. Standardized peri-operative blood salvage techniques were utilized in all 60 patients. In the latter 30 patients, tTXA soaked sponges (1 g mixed in 500 ml Normal Saline) was utilised for wound packing during the entire surgical procedure compared to dry sponges as used in the former 30 patients. Both the groups were compared for the magnitude of deformity corrected, EBL per level fused, total EBL, blood transfused, drain output and peri-operative events. RESULTS: Sixty AIS patients (mean age 14.4 yrs, 43 females, mean BMI 21.5, mean levels 10.7) were included. Both groups achieved similar change in Coronal Cobb correction. The EBVL (Estimated blood volume loss) % lost in the topical TXA group was 38% less than the control group (11.2 vs. 18.3%, p = 0.006). Similarly, the EBL/level was significantly lower in the topical TXA group (41 ± 30 ml vs. 57 ± 26 ml, p = 0.03). Three of 30 patients in the control group required at least 1 unit of blood transfusion, whereas only 1 patient in the topical TXA group required transfusion (10 vs. 3.3%, p = 0.001). No differences were noted in post-operative drain output, change in hemoglobin levels, and peri-operative complication rates. CONCLUSION: When used as an adjunct to the conventional blood salvage techniques in spinal deformity correction procedures, the use of tTXA resulted in reduced operative blood loss, and blood transfusion requirements.

Residual lumbar hyperlordosis is associated with worsened hip status 5 years after scoliosis correction in non-ambulant patients with cerebral palsy.

BACKGROUND: Cerebral palsy (CP) is a static encephalopathy with progressive musculoskeletal pathology. Non-ambulant children (GMFCS IV and V) with CP have high rates of spastic hip disease and neuromuscular scoliosis. The effect of spinal fusion and spinal deformity on hip dislocation following total hip arthroplasty has been well studied, however in CP this remains largely unknown. This study aimed to identify factors associated with worsening postoperative hip status (WHS) following corrective spinal fusion in children with GMFCS IV and V CP. METHODS: Retrospective review of GMFSC IV and V CP patients in a prospective multicenter database undergoing spinal fusion, with 5 years follow-up. WHS was determined by permutations of baseline (BL), 1 year, 2 years, and 5 years hip status and defined by a change from an enlocated hip at BL that became subluxated, dislocated or resected post-op, or a subluxated hip that became dislocated or resected. Hip status was analyzed against patient demographics, hip position, surgical variables, and coronal and sagittal spinal alignment parameters. Cutoff values for parameters at which the relationship with hip status was significant was determined using receiver operating characteristic curves. Logistic regression determined odds ratios for predictors of WHS. RESULTS: Eighty four patients were included. 37 (44%) had WHS postoperatively. ROC analysis and logistic regression demonstrated that the only spinopelvic alignment parameter that significantly correlated with WHS was lumbar hyperlordosis (T12-L5) > 60° (p = 0.028), OR = 2.77 (CI 1.10-6.94). All patients showed an increase in pre-to-postop LL. Change in LL pre-to-postop was no different between groups (p = 0.318), however the WHS group was more lordotic at BL and postop (pre44°/post58° vs pre32°/post51° in the no change group). Age, sex, Risser, hip position, levels fused, coronal parameters, global sagittal alignment (SVA), thoracic kyphosis, and reoperation were not associated with WHS. CONCLUSION: Postoperative hyperlordosis(> 60°) is a risk factor for WHS at 5 years after spinal fusion in non-ambulant CP patients. WHS likely relates to anterior pelvic tilt and functional acetabular retroversion due to hyperlordosis, as well as loss of protective lumbopelvic motion causing anterior femoracetabular impingement. LEVEL OF EVIDENCE: III.

Age and Gender Confound PROMIS Scores in Spine Patients With Back and Neck Pain.

STUDY DESIGN: This was a single-center retrospective review. OBJECTIVES: To explore how age and gender affect PROMIS scores compared with traditional health-related quality of life (HRQL) in spine patients. METHODS: Patients presenting with a primary complaint of back pain (BP) or neck pain (NP) were included. Legacy HRQLs were Oswestry Disability Index (ODI), Neck Disability Index (NDI), and Visual Analogue Scale (VAS). PROMIS Physical Function (PF), Pain Intensity (Int), and Pain Interference (Inf) were also administered to patients in a clinical setting. Patients were grouped by chief complaint, age (18-44, 45-64, 65+ years) and gender. Two parallel analyses were conducted to identify the effects of age and gender on patient-reported outcomes. Age groups were compared after propensity-score matching by VAS-pain and gender. Separately, genders were compared after propensity-score matching by age and VAS-pain. RESULTS: A total of 484 BP and 128 NP patients were matched into gender cohorts (n = 201 in each BP group, 46 in each NP group). Among BP patients, female patients demonstrated worse disability by ODI (44.15 vs 38.45, P = .005); PROMIS-PF did not differ by gender. Among NP patients, neither legacy HRQLs nor PROMIS differed by gender when controlling for NP and age. BP and NP patients were matched into age cohorts (n = 135 in each BP group and n = 14 in each BP group). Among BP patients, ANOVA revealed differences between groups when controlling for BP and gender: ODI (P < .001), PROMIS-PF (P = .018), PROMIS-Int (P < .001) PROMIS-Inf (P < .001). Among NP patients, matched age groups differed significantly in terms of NDI (P = .032) and PROMIS-PF (P = .022) but not PROMIS-Int or PROMIS-Inf. CONCLUSIONS: Age and gender confound traditional HRQLs as well as PROMIS domains. However, PROMIS offers age and gender-specific scores, which traditional HRQLs lack.

Characteristics and Trends of the Most Cited Spine Publications.

STUDY DESIGN: Bibliometric literature review. OBJECTIVE: The aim of this study was to recognize and analyze the most frequently cited manuscripts published in the journal Spine. SUMMARY OF BACKGROUND DATA: Although the journal Spine is considered a premiere location for distributing influential spine research, no previous study has evaluated which of their publications have had the most impact. Knowledge and appreciation of the most influential Spine publications can guide and inspire future research endeavors. METHODS: Using the Scopus database, the 100 most cited articles published in Spine were accessed. The frequency of citations, year of publication, country of origin, level-of-evidence (LOE), article type, and contributing authors/institutions were recorded. The 10 most cited articles (per year) from the past decade were also determined. RESULTS: "Guidelines For The Process Of Cross-Cultural Adaptation Of Self-Report Measures" by Beaton DE was the most cited article with 2960 citations. 2000 to 2009 (n = 46) was the most productive period. A LOE of III (n = 35) followed by II (n = 34) were the most common. Deyo RA (n = 8), Bombardier C (n = 6), and Waddell G (n = 6) produced the most articles. University of Washington (n = 8) and University of Toronto (n = 8) ranked first for institutional output. Clinical Outcome (n = 28) was the most recurring article topic. The United States (n = 51) ranked first for country of origin. CONCLUSION: Using citation analysis as an objective proxy for influence, certain publications can be distinguished from others due to their lasting impact and recognition from peers. Of the top cited Spine publications, many pertained to clinical outcomes (28%) and had a LOE of I, II, or III (60%). Although older publications have had longer time to accrue citations, those in the most recent decade comprise this list almost 2:1. Knowledge of these "classic" publications allows for a better overall understanding of the diagnosis, management, and future direction of spine health care.Level of Evidence: 3.

A Focused Gap Year Program in Orthopaedic Research: An 18-Year Experience.

INTRODUCTION: Students seek gap years to enhance knowledge and improve chances of professional success. Although many institutions offer research opportunities, no studies have examined outcomes after these experiences. This study evaluates a dedicated year of orthopaedic research on a cohort's ultimate orthopaedic surgery match rate. METHODS: From 2001 to 2018, 129 learners spent a year with our Department of Orthopedic Surgery at a major academic medical center. The students were either completing a gap year after college, during or after medical school, or after an unsuccessful match. Participants were asked to respond to a survey, which included demographics, educational information, and metrics related to the program. For the subcohort of students who ranked orthopaedic surgery, the match rate was compared with the mean for the US orthopaedic surgery match rates from 2006 to 2018 using a chi-square analysis. In addition, a Mann-Whitney U test was used to compare the number of publications before and after the year. RESULTS: One hundred three students (80%) returned completed questionnaires. Of all learners who applied to and ranked orthopaedic surgery, 91% matched into an orthopaedic surgery residency program. These results compared favorably with the US orthopaedic match from 2006 to 2018 (67.9%; P < 0.001), despite a 4-point lower United States Medical Licensing Examination (USMLE) Step 1 score for the research cohort. Finally, the research cohort had a greater percentage of women (23%) and minorities (40%) than the proportion of woman and minority practicing orthopaedic surgeons. CONCLUSION: Students who completed a gap year in research matched into orthopaedics at a higher rate than the national average, despite a lower Step score. Mentors may also target traditionally underrepresented groups to help increase the pool of diverse applicants.

The Relationship Between 3-dimensional Spinal Alignment, Thoracic Volume, and Pulmonary Function in Surgical Correction of Adolescent Idiopathic Scoliosis: A 5-year Follow-up Study.

STUDY DESIGN: Retrospective review of a prospective multicenter database. OBJECTIVE: The aim of this study was to study the effects of thoracic kyphosis (TK) restoration in adolescent idiopathic scoliosis (AIS) Type 1 and 2 curves on postoperative thoracic volume (TV) and pulmonary function. SUMMARY OF BACKGROUND DATA: Surgical correction of AIS is advocated to preserve or improve pulmonary function, prevent progressive deformity and pain, and improve self-appearance. Restoration of sagittal and 3D alignment, particularly TK, has become increasingly emphasized in efforts to improve pulmonary function, TVs, sagittal balance, and prevent adjacent-segment degeneration and deformity. METHODS: AIS patients 10 to 21years undergoing surgical correction of Lenke Type 1 and 2 curves with baseline, 1-erect-postoperative, and 5-year (5Y) postoperative visits including stereoradiographic assessment and pulmonary function tests (PFTs) were included. 3D-radiographic analysis was performed to assess spinal-alignment, chest-wall, and rib-cage dimensions at each time point. Outcome variables were analyzed between time points with one-way analysis of variance and between variables with linear regression analysis. RESULTS: Thirty-nine patients (37 females, 14.4 ± 2.2 years) were included. 3D-spinal-alignment analyses demonstrated significant reduction in preoperative to first-erect thoracic and lumbar Cobb-angles, an increase in TK:T2-12 (19.67°-39.69°) and TK:T5-12 (9.47°-28.05°), and reduction in apical vertebral rotation (AVR) (P < 0.001 for all). Spinal-alignment remained stable from 1-erect to 5Y. 3D rib-cage analysis demonstrated small reductions in baseline to first-erect depth (145-139 mm), width (235-232 mm), and increase in height (219-230 mm, P < 0.01), but no significant change in volume (5161-5222 cm,P = 0.184). From 1-erect to 5Y, significant increases in depth, width, height, and volume (all P < 0.001) occurred. PFTs showed preoperative to 5Y improvement in first second of Forced Expiratory Volume (FEV1) (2.74-2.98 L, P = 0.005) and forced vital capacity (FVC) (3.23-3.47 L, P = 0.008); however, total lung capacity (TLC) did not change (P = 0.517). Percent-predicted TLC decreased (Pre: 101.3% to 5Y: 89.3%, P < 0.001); however, percent-predicted forced expiratory volume and FVC did not (P = 0.112 and P = 0.068). CONCLUSION: Although TK increases, coronal-Cobb and AVR decrease postoperatively; these do not directly influence TV, which increases from 1-erect to 5Y due to growth, corresponding with increases in FEV1 and FVC at 5Y; however, surgical restoration of kyphosis does not directly improve pulmonary function. LEVEL OF EVIDENCE: 3.

Spino-femoral muscles affect sagittal alignment and compensatory recruitment: a new look into soft tissues in adult spinal deformity.

OBJECTIVE: To quantify muscle characteristics (volumes and fat infiltration) and identify their relationship to sagittal malalignment and compensatory mechanism recruitment. METHODS: Female adult spinal deformity patients underwent T1-weighted MRI with a 2-point Dixon protocol from the proximal tibia up to the T12 vertebra. 3D reconstructions of 17 muscles, including extensors and flexors of spine, hip and knee, were obtained. Muscle volume standardized by bone volume and percentage of fat infiltration (Pfat) were calculated. Correlations and regressions were performed. RESULTS: A total of 22 patients were included. Significant correlations were observed between sagittal alignment and muscle parameters. Fat infiltration of the hip and knee flexors and extensors correlated with larger C7-S1 SVA. Smaller spinal flexor/extensor volumes correlated with greater PI-LL mismatch (r = - 0.45 and - 0.51). Linear regression identified volume of biceps femoris as only predictor for PT (R2 = 0.34, p = 0.005) and Pfat of gluteus minimus as only predictor for SVA (R2 = 0.45, p = 0.001). Sagittally malaligned patients with larger PT (26.8° vs. 17.2°) had significantly smaller volume and larger Pfat of gluteus medius, gluteus minimus and biceps femoris, but similar values for gluteus maximus, the hip extensor. CONCLUSION: This study is the first to quantify the relationship between degeneration of spino-femoral muscles and sagittal malalignment. This pathoanatomical study identifies the close relationship between gluteal, hamstring muscles and PT, SVA, which deepens our understanding of the underlying etiology that contributes to adult spinal deformity.

Mandibular slope: a reproducible and simple measure of horizontal gaze.

STUDY DESIGN: This study is a single-center retrospective radiographic review. OBJECTIVES: The objective of this study is to evaluate a novel measurement parameter, mandibular slope (MS), as a measure of horizontal gaze. INTRODUCTION: Assessment of sagittal spinal alignment is essential in the evaluation of spinal deformity patients. Ability to achieve a horizontal gaze, a parameter of sagittal alignment, is needed for the performance of daily activities. Standard measures of horizontal gaze, including the gold-standard chin-brow to vertical angle (CBVA) and the surrogate measures McGregor's line (McGS) and Chamberlain's line (CS), require high-quality imaging, precise head positioning, and reliance on difficult to view visual landmarks. A novel measurement parameter, MS, utilizing the caudal margin of the mandible on standard lateral spine radiographs is proposed. METHODS: 90 radiographs from spine deformity patients with or without spinal implants from a single center were evaluated. Three spine surgery fellows independently measured CBVA, McGS, CS, and MS at two timepoints at least one week apart to assess accuracy and reliability. MS was measured as the angle created by the inferior edge of the mandibular body and the horizontal. Formulas for calculating CBVA based on the above parameters were derived and compared to the actual CBVA. RESULTS: Mean age was 49.7 years, 76 females and 14 males. CBVA correlated with CS, McGS, and MS, r = 0.85, 0.81, and 0.80, respectively (p < 0.001). Standard error between real CBVA and calculated CBVA using CS (0.4 ± 4.79) and McGS (0.4 ± 3.9) was higher than that calculated using MS (- 0.2 ± 4.3). ICC demonstrated the highest inter-observer reliability with MS (0.999). MS had the highest intra-observer reliabilities 0.975, 0.981, and 0.988 (p < 0.001); CS and McGS also demonstrated high intra-observer reliability. CONCLUSIONS: MS is a promising measure of horizontal gaze that correlates highly with CBVA, has excellent intra- and inter-observer reliability with CBVA, and is easily measured using standard lateral spine radiographs.