Faculty Bibliography

OBJECTIVE:It is being increasingly recognized that adult cervical deformity (ACD) is correlated with significant pain, myelopathy, and disability, and that patients who undergo deformity correction gain significant benefit. However, there are no defined thresholds of minimum clinically important difference (MCID) in Neck Disability Index (NDI) and modified Japanese Orthopaedic Association (mJOA) scores. METHODS:Patients of interest were consecutive patients with ACD who underwent cervical deformity correction. ACD was defined as C2-7 sagittal Cobb angle ≥ 10° (kyphosis), C2-7 coronal Cobb angle ≥ 10° (cervical scoliosis), C2-7 sagittal vertical axis ≥ 4 cm, and/or chin-brow vertical angle ≥ 25°. Data were obtained from a consecutive cohort of patients from a multiinstitutional prospective database maintained across 13 sites. Distribution-based MCID, anchor-based MCID, and minimally detectable measurement difference (MDMD) were calculated. RESULTS:A total of 73 patients met inclusion criteria and had sufficient 1-year follow-up. In the cohort, 42 patients (57.5%) were female. The mean age at the time of surgery was 62.23 years, and average body mass index was 29.28. The mean preoperative NDI was 46.49 and mJOA was 13.17. There was significant improvement in NDI at 1 year (46.49 vs 37.04; p = 0.0001). There was no significant difference in preoperative and 1-year mJOA (13.17 vs 13.7; p = 0.12). Using multiple techniques to yield MCID thresholds specific to the ACD population, the authors obtained values of 5.42 to 7.48 for the NDI, and 1.00 to 1.39 for the mJOA. The MDMD was 6.4 for the NDI, and 1.8 for the mJOA. Therefore, based on their results, the authors recommend using an MCID threshold of 1.8 for the mJOA, and 7.0 for the NDI in patients with ACD. CONCLUSIONS:The ACD-specific MCID thresholds for NDI and mJOA are similar to the reported MCID following surgery for degenerative cervical disease. Additional studies are needed to verify these findings. Nonetheless, the findings here will be useful for future studies evaluating the success of surgery for patients with ACD undergoing deformity correction.

Study Design/UNASSIGNED:Retrospective review of single institution. Objective/UNASSIGNED:To assess the relationship between Patient-Reported Outcomes Measurement Information System (PROMIS) and Oswestry Disability Index (ODI) scores in thoracolumbar patients. Methods/UNASSIGNED:Included: Patients ≥18 years with a thoracolumbar spine condition (spinal stenosis, disc herniation, low back pain, disc degeneration, spondylolysis). Bivariate correlations assessed the linear relationships between ODI and PROMIS (Physical Function, Pain Intensity, and Pain Interference). Correlation cutoffs assessed patients with high and low correlation between ODI and PROMIS. Linear regression predicted the relationship of ODI to PROMIS. Results/UNASSIGNED:= 0.499) of the variance in Pain Intensity score. Conclusions/UNASSIGNED:There is a large amount of variability with PROMIS that cannot be accounted for with ODI. ODI questions regarding walking, social life, and lifting ability correlate strongly with PROMIS while sitting, standing, and sleeping do not. These results reinforce the utility of PROMIS as a valid assessment for low back disability, while indicating the need for further evaluation of the factors responsible for variation between PROMIS and ODI.

Chiari Malformation type 1 (CM-I) is congenital or an acquired anomaly of the hind brain; develops when the cerebellar tonsils recede downwards below the foramen magnum. Recurrent post tussive suboccipital headache is the common presentation in a pregnant woman and the diagnosis is usually missed or delayed due to lack of formal understanding of this neurological pathology. Much has been written regarding presentation, morphology and the treatment of CM-I; however, little is known when the etiology is acquired or an iatrogenic in its evolution. Similarly, unknown is the progression of CM-I (diagnosed or undiagnosed) in pregnancy. The objective of this study is to elucidate the causes of progression of CM-I in pregnancy, and how this can be avoided. A detailed literature review has been conducted to find the case reports or case studies on association of CM-I in pregnancy; therefore, the risk factors regarding the progression have been sought. There is a lack of literature on timing, mode of anesthesia, and the management of CM-I. Moreover, authors have sought a questionnaire to screen these patients at pre-conception, intrapartum visits if, the initial diagnosis is delayed. Crucial points of concern including but not limited to the diagnosis, pre-conception counseling, timing of intervention during pregnancy, and mode of anesthesia, have been discussed in detail. In summary, a formal management algorithm has been proposed to avoid the rapid progression of this complex neurological pathology especially, in women of child bearing age and/or during pregnancy.

There has been limited discussion as to whether spine surgery patients are benefiting from shorter in-patient hospital stays or if they are incurring higher rates of readmission and complications secondary to shortened length of stays. Included in this study were 237,446 spine patients >18yrs and excluding infection. Patients with Clavien Grade 5 complications in 2015 had the lowest mean time to readmission after initial surgery in all years at 12.44 ± 9.03 days. Pearson bivariate correlations between LOS ≤ 1 day and decreasing days to readmission was the strongest in 2016.). Logistic regression analysis found that LOS ≤ 1 day showed an overall increase in the odds of hospital readmission from 2012 to 2016 (2.29 [2.00-2.63], 2.33 [2.08-2.61], 2.35 [2.11-2.61], 2.27 [2.06-2.49], 2.33 [2.14-2.54], all p < 0.001).

OBJECTIVE:Our aim was to define a treatment strategy for patients with severe cervical deformity(sCD). METHODS:Surgical patients with sCD were isolated based on preop radiographic parameters. We sent 10 sCD cases to 7 surgeons to find consensus on approach, upper instrumented vertebrae (UIV), lower instrumented vertebrae (LIV), osteotomy. We performed a descriptive analysis and created a treatment algorithm from the survey then analyzed a database of surgical patients to find the frequency of following our algorithm. RESULTS:We found consensus on 7 cases for posterior approach due to cervicothoracic deformity and of 15 patients within our sCD database that had cervicothoracic deformity, 13/15 had posterior approach. There was consensus on 2 cases for antero-posterior approach due to local kyphosis and of 25 patients that had local kyphosis, 18/25 had an anterior approach. In 4 cases there was consensus of UIV of C2 and of 35 cases that had posterior fusion >6 levels, 20/35 had a UIV of C2. In 3 cases there was consensus of a LIV below a previously fused spine. Of 36 patients that had a fusion of T6 or higher, 34 had a LIV below the previous UIV. In 6 cases there was consensus against an osteotomy due to cervical spine flexibility and 9/12 patients that had an osteotomy in our database had no flexibility on dynamic radiographs. CONCLUSION/CONCLUSIONS:We outline here an algorithm for deciding approach, UIV, LIV and whether to do an osteotomy for patients with sCD based on consensus recommendations amongst spine surgeons.

Hospital-acquired conditions (HACs) have been the focus of recent initiatives by the Centers for Medicare and Medicaid Services in an effort to improve patient safety and outcomes. Spine surgery can be complex and may carry significant comorbidity burden, including so called "never events." The objective was to determine the rates of common HACs that occur within 30-days post-operatively for elective spine surgeries and compare them to other common surgical procedures. Patients: >18 y/o undergoing elective spine surgery were identified in the American College of Surgeons' NSQIP database from 2005 to 2013. Patients were stratified by whether they experienced >1 HAC, then compared to those undergoing other procedures including bariatric surgery, THA and TKA. Of the 90,551 spine surgery patients, 3021 (3.3%) developed at least one HAC. SSI was the most common (1.4%), followed by UTI (1.3%), and VTE (0.8%). Rates of HACs in spine surgery were significantly higher than other elective procedures including bariatric surgery (2.8%) and THA (2.8%) (both p < 0.001). Spine surgery and TKA patients had similar rates of HACs(3.3% vs 3.4%, p = 0.287), though spine patients experienced higher rates of SSI (1.4%vs0.8%, p < 0.001) and UTI (1.3%vs1.1%, p < 0.001) but lower rates of VTE (0.8%vs1.6%, p < 0.001). Spine surgery patients had lower rates of HACs overall (3.3%vs5.9%) when compared to cardiothoracic surgery patients (p < 0.001). When compared to other surgery types, spine procedures were associated with higher HACs than bariatric surgery patients and knee and hip arthroplasties overall but lower HAC rates than patients undergoing cardiothoracic surgery.

BACKGROUND:Little is known of how frailty, a dynamic measure of physiological age, progresses relative to age or disability status. Operative treatment of adult spinal deformity (ASD) may play a role in frailty remediation and maintenance. PURPOSE/OBJECTIVE:Compare frailty status, severe frailty development, and factors influencing severe frailty development among ASD patients undergoing operative or non-operative treatment. DESIGN/METHODS:Retrospective review with maximum follow up of 3 years. SETTING/METHODS:Prospective, multicenter, ASD database. PARTICIPANTS/METHODS:Patients were consecutively enrolled from 13 participating centers. INCLUSION CRITERIA/METHODS:≥18 years undergoing either operative or non-operative treatment for ASD, exclusion criteria: spinal deformity of neuromuscular etiology, presence of active infection, or malignancy. The mean age of the participants analyzed were 54.9 for the operative cohort and 55.0 for the non-operative cohort. MAIN OUTCOMES/RESULTS:Frailty status, severe frailty development and factors influencing severe frailty development. METHODS:ASD patients (coronal scoliosis≥20°, sagittal vertical axis (SVA)≥5cm, Pelvic Tilt (PT)≥25°, or thoracic kyphosis≥60°) >18y/o, with Base Line (BL) frailty scores were included. Frailty was scored from 0-1 (not frail: <0.3, frail 0.3-0.5, severe frailty >0.5) through the use of ASD-FI which has been validated using the International Spine Study Group (ISSG) ASD database, European Spine Study Group (ESSG) ASD database, and the Scoli-RISK-1 Patient Database. The International Spine Study Group (ISSG) is funded through research grants from DePuy Synthes and individual donations, and supported the current work. Operative (Op) and Non-Operative (Non-Op) patients were propensity matched. T-tests compared frailty among treatment groups and BL, 1Y, 2Y, and ≥3Y. An actuarial Kaplan-Meier survivorship analysis with Log Rank (Mantel-Cox) test, adjusting for patients lost to follow-up, determined probability of severe frailty development. Multivariate Cox Regressions gauged the effect of sagittal malalignment, patient and surgical details on severe frailty development. RESULTS:The analysis includes 472 patients (236 Op, 236 Non-Op) selected by propensity score matching from a cohort of 1172. Demographics and comorbidities were similar between groups (p>0.05). Op exhibited decreased frailty at all follow up intervals compared to BL (BL:0.22 vs Y1:0.18; Y2:0.16; Y3:0.15, all p<0.001). Non-Op displayed similar frailty from BL to 2Y follow up, and increased frailty at 3Y follow up (0.23 vs 0.25, p=0.014). Compared to Non-Op, Op had lower frailty at 1Y (0.18 vs 0.24), 2Y (0.16 vs 0.23) and 3Y (0.15 vs 0.25) (all p<0.001). Cumulative probability of maintaining non-severe frailty was (Op:97.7%, Non-Op:94.5%) at 1Y, (Op:95.1%, Non-Op:90.4%) at 2Y, and (Op:95.1%, Non-Op:89.1%) at ≥3Y, (p=0.018). Amongst all patients, baseline depression (HR: 2.688[1.172-6.167], p=0.020), NRS back pain scores (HR: 1.247[1.012-1.537], p=0.039), and non-operative treatment (HR: 2.785[1.167-6.659], p=0.021) predicted severe frailty development with having a HR>1.0 and p-value<0.05. Among operative patients, 6-week postoperative residual SVA malalignment (SRS-Schwab SVA + modifier) (HR: 15.034[1.922-116.940], p=0.010) predicted severe frailty development indicated by having a HR>1.0 and p-value <0.05. CONCLUSIONS:Non-Op patients were more likely to develop severe frailty, and at a quicker rate. Baseline depression, increased NRS back pain scores, non-operative treatment, and postoperative sagittal malalignment at 6-week follow-up significantly predicted severe frailty development. Operative intervention and postoperative sagittal balance appear to play significant roles in frailty remediation and maintenance in adult spinal deformity patients. Frailty is one factor, in a multifactorial conservation, that may be considered when determining operative or non-operative values for ASD patients. Operating before the onset of severe frailty, may result in a lower complication risk and better long term clinical outcomes. LEVEL OF EVIDENCE/METHODS:III.

OBJECT/OBJECTIVE:This case series examined patients undergoing caudal extension of prior fusion without alteration of the prior UIV to assess patient outcomes and rates of PJK/PJF. METHODS:Patients eligible for 2-year minimum follow-up undergoing caudal extension of prior fusion with unchanged UIVs were identified. These patients were evaluated for PJK/PJF, and patient reported outcomes were recorded. RESULTS:In total, 40 patients were included. Mean follow-up duration was 2.2 years (SD 0.3). Patients in this cohort had poor preoperative sagittal alignment (PI-LL 26.7°, TPA 29.0°, SVA 93.4mm) and achieved substantial sagittal correction (ΔSVA -62.2mm, ΔPI-LL -19.8°, ΔTPA -11.1°) following caudal extension surgery. At final follow-up, there was a 0% rate of PJF among patients undergoing caudal extension of previous fusion without creation of a new UIV, but 27.5% of patients experienced PJK. Patients experienced significant improvement in both ODI and SRS-22r total score at 2-years post-operatively (p<0.05). In total, 7.5% (n=3) of patients underwent further revision, at an average of 1.1 years (SD 0.54) after the surgery with unaltered UIV. All three of these patients underwent revision for rod fracture with no revisions for PJK/PJF. CONCLUSIONS:Patients undergoing caudal extension of previous fusions for sagittal alignment correction have high rates of clinical success, low revision surgery rates, and very low rates of PJF. Minimizing repetitive tissue trauma at the UIV may result in decreased PJF risk, as the PJF rate in this cohort of unaltered UIV patients is below historical PJF rates of patients undergoing sagittal balance correction.

OBJECT/OBJECTIVE:Sexual function is an important factor which contributes to quality of life. ASD patients may have sexual limitations due to lumbar spinal stiffness which may be affected by long-segment fusion. METHODS:This study utilized a multi-center, prospectively defined, consecutive cohort of ASD patients. The primary outcome in this study was the LSDI question 10: "Choose the statement that best describes the effect of low back stiffness on your ability to engage in sexual intercourse". RESULTS:In total, 368 patients were included in this study, including 76 males and 292 females of which 80.7% (n=293) underwent 9 or more level fusion and 74.4% (n=270) had pelvic fixation. Baseline LSDI sexual function scores averaged 1.7 (SD 1.3), which improved to 1.3 (SD 1.2) at 2-year follow-up (p = 0.0008). After adjusting for confounding factors, worse LSDI sexual function score was strongly associated with worse ODI, SRS total, and SF-36 PCS and MCS scores at both baseline and 2-year follow-up (p<0.05 for all comparisons). Predictors of poorer baseline sexual function included older age, increased SVA, and increased back pain (p<0.05 for all comparisons). Predictors of improvement in sexual function at 2-year follow-up included SVA improvement (p=0.0032) and decreased postoperative back pain (p<0.0001). CONCLUSIONS:This study found that sexual dysfunction scores due to lumbar stiffness significantly improved following surgery for ASD. Additionally, lumbar stiffness related sexual dysfunction is strongly related to overall outcome measured by ODI and SRS total score, highlighting the importance of sexual health on overall outcome in ASD patients.