Faculty Bibliography

STUDY DESIGN:Retrospective review from a single institution. OBJECTIVES:To evaluate intraoperative T1-pelvic angle (TPA), T4PA, and T9PA as predictors of postoperative global alignment after adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA:Malalignment following adult spinal surgery is associated with disability and correlates with health-related quality of life. Preoperative planning and intraoperative verification are crucial for optimal postoperative outcomes. Currently, only pelvic incidence minus lumbar lordosis (PI-LL) mismatch has been used to assess intraoperative correction. METHODS:Patients undergoing ≥4-level spinal fusion with full-length pre-, intra-, and first postoperative calibrated radiographs were included from a single institution. Alignment measurements were obtained for sagittal vertical axis (SVA), PI-LL, TPA, T4PA, and T9PA. The whole cohort was divided into upper thoracic (UT: UIV > T7) and lower thoracic fusions (LT: UIV < T7). Change was assessed between phases, and a subanalysis was included for UT and LT groups to compare alignment changes for differing extent of proximal fusion in the sagittal plane. RESULTS:Eighty patients (mean 63.4 years, 70% female, mean levels fused 11.9) underwent significant ASD correction (ΔPI-LL = 22.1°; ΔTPA = 13.8°). For all, intraoperative TPA, T4PA, and T9PA correlated with postoperative SVA (range, r = 0.41-0.59), whereas intraoperative PI-LL correlated less (r = 0.38). For UT (n = 49), all spinopelvic angles and LL were similar intraoperative to postoperatively (p > .09). For LT (n = 31), intraoperative and postoperative T9PA and LL were similar (p > .10) but TPA and T4PA differed (p < .02). For UT, all intraoperative and postoperative spinopelvic angles strongly correlated (r = 0.8-0.9). For LT, intraoperative to postoperative T9PA strongly correlated (r = 0.83) and TPA, T4PA, and LL correlated moderately (r = 0.65-0.70). LT trended toward more reciprocal kyphosis postoperatively (8.1° vs. 2.6°; p = .059). CONCLUSIONS:Intraoperative measurements of TPA, T4PA, and T9PA correlated better with postoperative global alignment than PI-LL, demonstrating their utility in confirming alignment goals. When comparing intraoperative to postoperative films, only T9PA was similar in LT whereas all spinopelvic angles were similar in UT. Reciprocal kyphosis in unfused segments of LT fusions may account for difference in TPA and T4PA from intraoperative to postoperative films. LEVEL OF EVIDENCE:Level III.

STUDY DESIGN/METHODS:Retrospective review OBJECTIVE.: Develop a simplified frailty index for CD patients SUMMARY OF BACKGROUND DATA.: To improve preoperative risk stratification for surgical cervical deformity (CD) patients, a CD frailty index (CD-FI) incorporating 40 health deficits was developed. While novel, the CD-FI is clinically impractical due to the large number of factors needed for its calculation. To increase clinical utility, a simpler, modified CD-FI (mCD-FI) is necessary. METHODS:CD patients (C2-C7 Cobb>10°, CL>10°, cSVA>4 cm, or CBVA>25°) >18yr with preoperative CD-FI component factors. Pearson bivariate correlation assessed relationships between component deficits of the CD-FI and overall CD-FI score. Top deficits contributing to CD-FI score were included in multiple stepwise regression models. Deficits from model with largest R were dichotomized, and the mean score of all deficits calculated, resulting in mCD-FI score from 0 to 1. Patients were stratified by mCD-FI: Not Frail (NF, <0.3), Frail (0.3-0.5), Severely Frail (SF, >0.5). Means comparison tests established correlations between frailty category and clinical outcomes. RESULTS:Included: 121 CD patients (61 ± 11yr, 60%F). Multiple stepwise regression models identified 15 deficits as responsible for 86% of the variation in CD-FI; these factors were used to construct the mCD-FI. Overall, mean mCD-FI was 0.31 ± 0.14. Breakdown of patients by mCD-FI category: NF: 47.9%, Frail: 46.3%, SF: 5.8%. Compared to NF and Frail, SF patients had the longest inpatient hospital stays (P = 0.042), as well as greater baseline neck pain (P = 0.033), inferior NDI scores (P<0.001) and inferior EQ-5D scores (P < 0.001). Frail patients had higher odds of superficial infection (OR:1.1[1.0-1.2]), and SF patients had increased odds of mortality (OR:8.3[1.3-53.9]). CONCLUSIONS:Increased frailty, assessed by mCD-FI, correlated with increased length of stay, neck pain, and decreased health-related quality of life. Frail patients were at greater risk for infection, and severely frail patients had greater odds of mortality. This relationship between frailty and clinical outcomes suggests that mCD-FI offers clinical utility as a preoperative risk stratification tool. LEVEL OF EVIDENCE/METHODS:3.

STUDY DESIGN/METHODS:A retrospective analysis of a patient-reported outcomes database from a single institution from December 2016 to April 2017. OBJECTIVE:To validate the association of PROMIS with NDI in patients with neck pain and examine each instruments ability to capture concomitant arm pain and concomitant back pain. SUMMARY OF BACKGROUND DATA/BACKGROUND:PROMIS has been increasingly utilized and its computer adapted testing methodology improves assessment of pain and disability. However literature is lacking regarding how these instruments perform in neck pain patients with concomitant arm pain or back pain. METHODS:Inclusion criteria were age>18years and a primary complaint of neck pain. The NDI, VAS Back, Neck, Arm and Leg, and PROMIS Physical Function, Pain Intensity, and Pain Interference questionnaires were administered. Propensity score matching was performed to compare patients with high and low back and arm pain while controlling for neck pain. Bivariate correlations and independent samples t-tests were performed to assess linear relationships and compare back and arm pain groups with PROMIS. RESULTS:130 patients were included. NDI correlated strongly to PROMIS Physical Function (r = -0.771, p < 0.001), Pain Intensity (r = 0.605, p < 0.001), and Pain Interference (r = 0.786, p < 0.001). VAS Neck and Arm Pain also correlated to the PROMIS Pain Intensity instrument (VAS Neck: r = 0.642, p < 0.001; VAS Arm: r = 0.376, p < 0.001).Following matching for neck pain, the high and low back pain groups each included 32 patients. There were significant differences in PROMIS Physical Function when high and low back pain groups were compared (39.07 vs 43.68, p = 0.031). No significant difference was found for any outcome metric for high and low arm pain groups. CONCLUSIONS:PROMIS instruments are capable of characterizing pain and disability in patients with neck pain and are sensitive to disability in regions adjacent to the neck. LEVEL OF EVIDENCE/METHODS:3.

OBJECTIVEThe Patient-Reported Outcomes Measurement Information System (PROMIS) has become increasingly popular due to computer adaptive testing methodology. This study aims to validate the association between PROMIS and legacy outcome metrics and compare PROMIS to legacy metrics in terms of ceiling and floor effects and questionnaire burden.METHODSA retrospective review of an outcomes database was performed at a single institution from December 2016 to April 2017. Inclusion criteria were age > 18 years and a chief complaint of back pain or neck pain. The PROMIS computer adaptive testing Pain Interference, Physical Function (PF), and Pain Intensity domains; Oswestry Disability Index (ODI); Neck Disability Index (NDI); and visual analog scale (VAS) back, VAS leg, VAS neck, and VAS arm were completed in random order. PROMIS was compared to legacy metrics in terms of the average number of questions needed to complete each questionnaire and the score distributions in the lower and higher bounds of scores.RESULTSA total of 494 patients with back pain and 130 patients with neck pain were included. For back pain, ODI showed a strong correlation with PROMIS-PF (R = -0.749, p < 0.001), Pain Intensity (R = 0.709, p < 0.001), and Pain Interference (R = 0.790, p < 0.001) domains. Additionally, the PROMIS Pain Intensity domain correlated to both VAS back and neck pain (R = 0.642, p < 0.001 for both). PROMIS-PF took significantly fewer questions to complete compared to the ODI (4.123 vs 9.906, p < 0.001). When assessing for instrument sensitivity, neither survey presented a significant ceiling and floor effect in the back pain population (ODI: 0.40% and 2.63%; PROMIS-PF: 0.60% and 1.41%). In the neck pain cohort, NDI showed a strong correlation with PROMIS-PF (R = 0.771, p < 0.001). Additionally, PROMIS Pain Intensity correlated to VAS neck (R = 0.642, p < 0.001). The mean number of questions required to complete the questionnaire was much lower for PROMIS-PF compared to NDI (4.417 vs 10, p < 0.001). There were no significant differences found in terms of ceiling and floor effects for neck complaints (NDI: 2.3% and 6.92%; PROMIS-PF: 0.00% and 5.38%) or back complaints (ODI: 0.40% and 2.63%; PROMIS-PF: 1.41% and 0.60%).CONCLUSIONSPROMIS correlates strongly with traditional disability measures in patients with back pain and neck pain. For both back and neck pain, the PROMIS-PF required patients to answer significantly fewer questions to achieve similar granularity. There were no significant differences in ceiling and floor effects for NDI or ODI when compared with the PROMIS-PF instrument.

Study Design/UNASSIGNED:Retrospective cohort study. Objective/UNASSIGNED:Determine the indications, complications, and clinical outcomes in patients requiring fusions from the cervical spine to the pelvis. Several investigators have examined fusions from the thoracic spine to the sacrum, but no similar study has been performed for cervical-to-pelvis fusions. Methods/UNASSIGNED:< .05 for all tests. Results/UNASSIGNED:< .01). Conclusion/UNASSIGNED:Proximal junctional kyphosis is the most common indication for patients requiring fusion to the cervical spine. Adult patients incur a significant risk of major complications and reoperations. However, significant improvement in SRS-22r outcomes are noted in these patients.

BACKGROUND AND IMPORTANCE/BACKGROUND:The use of nerve transfers to restore nerve function following traumatic avulsion injuries has been described, though there is still a paucity in the literature documenting technique and long-term outcomes for these procedures. The double Oberlin nerve transfer involves transferring fascicles from the median and ulnar nerves to the musculocutaneous nerve to restore elbow flexion in patients with a C5-C6 avulsion injury. The purpose of this case report is to present our indications and technique for a double Oberlin transfer in addition to exhibiting video footage at follow-up time points documenting the incremental improvement in elbow flexion following the injury. CLINICAL PRESENTATION/METHODS:The patient is a 25-yr old, left-hand dominant male who presented 5 mo following a motor vehicle accident. He had 0/5 biceps muscle strength on the left with a computed tomography myelogram that demonstrated pseudomeningoceles from C2-C3 to C7-T1 with root avulsions of C5 and C6. He was subsequently indicated for a double Oberlin nerve transfer to restore elbow flexion. CONCLUSION/CONCLUSIONS:In this case report, we present our technique and outcomes for a double Oberlin transfer with restoration of elbow flexion at 1-yr follow-up for a patient with traumatic brachial plexus injury. We believe that the double Oberlin transfer serves as a safe and effective method to restore elbow flexion in this patient population.

We developed a predictive model to describe risk factors for complications in cervical deformity surgeries. Cervical deformity (CD) surgical patients are growing in number, but remain under-studied in the literature. CD was defined as at least one of the following: C2-C7 Cobb >10°, CL >10°, cSVA >4 cm, CBVA >25°. Patient demographics and clinical data were assessed as risk factors for medical/surgical complications using multivariate regression models. 123 patients underwent CD surgery (60.6 yrs, 60.8% F). The most common complications were neurologic (24.4%), dysphagia (13.0%), cardiopulmonary (11.4%), infection (9.7%). 51 (41.5%) of patients experienced a medical complication and 73 (59.3%) had a surgical complication. An overall complication was predicted with high accuracy (AUC = 0.79) by the following combinations of factors: higher baseline EQ5D pain and lower baseline EQ5D anxiety/depression scores, and higher cervical and global SVA. A medical complication can be predicted by male gender, baseline mJOA score, and cervical SVA (AUC = 0.770). A surgical complication can be predicted by higher estimated blood loss, lower anxiety scores, and larger global SVA (AUC = 0.739). 64.2% of patients undergoing cervical deformity correction sustained any complication. While the most reliable predictor of the occurrence of a complication involved a cluster of risk factors, a radiographic baseline sagittal parameter of cervical SVA was the strongest isolated predictor for complications across categories. Although these findings are specific to a cervical population with moderate to severe deformities, collectively they can be utilized for pre-operative risk assessment and patient education.

BACKGROUND:Surgical treatments for adult cervical spinal deformity (ACSD) are often complex and have high complication rates. OBJECTIVE:To assess all-cause mortality following ACSD surgery. METHODS:ACSD patients presenting for surgical treatment were identified from a prospectively collected multicenter database. Clinical and surgical parameters and all-cause mortality were assessed. RESULTS:Of 123 ACSD patients, 120 (98%) had complete baseline data (mean age, 60.6 yr). The mean number of comorbidities per patient was 1.80, and 80% had at least 1 comorbidity. Surgical approaches included anterior only (15.8%), posterior only (50.0%), and combined anterior/posterior (34.2%). The mean number of vertebral levels fused was 8.0 (standard deviation [SD] = 4.5), and 23.3% had a 3-column osteotomy. Death was reported for 11 (9.2%) patients at a mean of 1.1 yr (SD = 0.76 yr; range = 7 d to 2 yr). Mean follow-up for living patients was 1.2 yr (SD = 0.64 yr). Causes of death included myocardial infarction (n = 2), pneumonia/cardiopulmonary failure (n = 2), sepsis (n = 1), obstructive sleep apnea/narcotics (n = 1), subsequently diagnosed amyotrophic lateral sclerosis (n = 1), burn injury related to home supplemental oxygen (n = 1), and unknown (n = 3). Deceased patients did not significantly differ from alive patients based on demographic, clinical, or surgical parameters assessed, except for a higher major complication rate (excluding mortality; 63.6% vs 22.0%, P = .006). CONCLUSION/CONCLUSIONS:All-cause mortality at a mean of 1.2 yr following surgery for ACSD was 9.2% in this prospective multicenter series. Causes of death were reflective of the overall high level of comorbidities. These findings may prove useful for treatment decision making and patient counseling in the context of the substantial impact of ACSD.

BACKGROUND CONTEXT/BACKGROUND:Distal Junctional Kyphosis (DJK) is a primary concern of surgeons correcting cervical deformity. Identifying patients and procedures at higher risk for developing this condition is paramount in improving patient selection and care. PURPOSE/OBJECTIVE:Develop a risk index for DJK development in the first year after surgery. STUDY DESIGN/SETTING/METHODS:Retrospective review of a prospective multicenter cervical deformity database. PATIENT SAMPLE/METHODS:). OUTCOME MEASURES/METHODS:Development of DJK at any time before 1 year. METHODS:distal vertebra, as well as a change in this angle by <-10 from baseline. Conditional Inference Decision Trees were used to identify factors predictive of DJK incidence and the cut-off points at which they have an effect. A conditional Variable-Importance table was constructed based on a non-replacement sampling set of 2000 Conditional Inference Trees. 12 influencing factors were found, binary logistic regression for each variable at significant cut-offs indicated their effect size. RESULTS:(OR:5.4 CI:2.20-13.23), and [6] C4_Tilt >56.7 (OR:5.0 CI:1.90-13.1).Clinically, combined approaches (OR:2.67 CI:1.21-5.89) and usage of Smith Petersen osteotomy (OR:2.55 CI:1.02-6.34) were the most important predictors for DJK. CONCLUSIONS:In a surgical cohort of cervical deformity patients, we found a 23.8% incidence of DJK. Different procedures and patient malalignment predicted incidence of DJK up to 1-year. Preoperative TS-CL, Cervical Kyphosis, SVA, and Cervical Lordosis all strongly predicted DJK at specific cut-off points. Knowledge of these factors will potentially help direct future study and strategy aimed at minimizing this potentially dramatic occurrence.

Purpose/UNASSIGNED:Evaluate the presence of new-onset cervical deformity (CD) in nonoperative adult spinal deformity (ASD) patients with extended follow-up, with consideration for predictors, prevalence, and impact on patient-reported outcomes. Methods/UNASSIGNED:Retrospective review of a prospective nonoperative ASD cohort. New onset CD patients at 1- (CD-1Y) and 2-year (CD-2Y) follow-up were defined as displaying baseline cervical alignment. Univariate analyses determined differences in radiographic parameters and outcome scores of CD and maintained-cervical-alignment patients. Multivariate binary logistic regression models determined new-onset CD predictors. Results/UNASSIGNED: > .05). Conclusions/UNASSIGNED:Cervical deformity can manifest in nonoperative ASD patients: 30.0% at 1-year follow-up, and 41.7% at 2-year follow-up. Progressive CD manifested independently of thoracolumbar profile changes. Increased baseline C2-C7 SVA, C2 slope, and prior surgical history increased new-onset CD odds at 1 and 2 years.