Faculty Bibliography

PURPOSE/OBJECTIVE:To compare the impact of lumbar lordosis correction achieved by cephalad versus caudal distribution on radiographic alignment and surgical outcomes among adult spinal deformity (ASD) patients. METHODS:Patients who underwent ASD surgery with uppermost instrumented vertebrae (UIV) at or above L1, had preoperative pelvic incidence-lumbar lordosis (PI-LL) > 10°, and had full-body radiographs available were included. Eligible patients were categorized by the focus of lordosis correction: caudal (L4-S1 lordosis between 35 and 45°) and cephalad lordosis-based correction. Patient demographics, preoperative and 2 years spinopelvic alignment and PROMs, and 2 years postoperative surgical complications were compared. RESULTS:In total, 187 (111 caudal and 76 cephalad) patients were included, with mean age of 66.2 years, 78.6% female, and mean frailty score of 3.6. Caudally-restored patients often had an upper thoracic UIV, sacrum/ilium LIV, longer length of fusion, and no lateral lumbar interbody fusion (LLIF) while cephaladly-restored patients had two or more LLIFs above L4 (p < 0.001). Preoperatively, there were no significant differences in radiographic alignment and PROMs between the two groups (p > 0.02). Two years postoperatively, caudally-restored patients had higher L1-S1 LL (p = 0.015) and L4-S1 LL (p < 0.001), and lower PI-LL (p = 0.039) and SVA (p = 0.001). In addition, they had higher SRS-22 activity (p = 0.045), pain (p = 0.047), appearance (p = 0.046), and total (p = 0.016) scores. Finally, they had lower rates of sensory deficits (p < 0.001), motor deficits (p = 0.003), implant failure (p = 0.092), and reoperation (p = 0.020). CONCLUSION/CONCLUSIONS:Caudal lordosis-based correction of spinal deformity patients was associated with higher PROMs and lower rates of neurologic deficits, implant failure, and revisions at 2 years. These findings, while subject to unmeasured confounding, indicate that great caution should be taken when considering cephalad-based correction of ASD.

OBJECTIVE:The aim of this study was to determine the rate of postoperative new-onset sacroiliac joint pain (SIJP) following adult spinal deformity (ASD) surgery with pelvic fixation. METHODS:Patients undergoing ASD surgery with pelvic fixation, without baseline SIJP, and with a minimum 1-year follow-up were included. Patients were screened for SIJP by self-reported buttock/groin pain and/or posterior superior iliac spine (PSIS) pain scores ≥ 4. Patients with positive results on questionnaires were indicated for an SIJ examination consisting of 5 provocative maneuvers with ≥ 3 positive examination findings considered to be indicative of SIJP. Types of pelvic fixation were then compared for rates of postoperative SIJP. RESULTS:A total of 346 patients were identified, with mean age of 65 (SD 10) years and BMI of 28 (SD 5); 71% of patients were female. Thirteen patients (4%) underwent SIJ fusion at the index procedure. At the 1-year follow-up, 82 patients (24%) had positive screening responses for SIJP on the questionnaire; 63 underwent an SIJ examination and only 3 patients (1%) had a positive result. At the 2-year follow-up, 138 patients were administered the SIJP screening questionnaire; 31 (22%) had a positive questionnaire response for SIJP, 17 underwent an SIJ examination, and only 2 patients (1%) had a positive result. There was no difference in SIJP between patients with traditional iliac fixation (n = 162, 0% at 1 and 2 years) and S2-alar-iliac screws (n = 184), where 2% developed SIJP by 1 (p = 0.25) and 2 (p = 0.52) years, respectively. There was also no difference in SIJP between patients with 4 points of pelvic fixation (n = 85, 0% at 1 and 2 years) and patients with fewer than 4 points of pelvic fixation (n = 261), where 1% (p = 0.57) and 2% (p > 0.99) developed SIJP at 1 and 2 years, respectively. Of the 79 patients with iliac crest harvesting, none developed SIJP at the 1- or 2-year follow-up. CONCLUSIONS:Based on examination, the incidence of de novo SIJP following ASD surgery with pelvic fixation is low: only 1% at the 1- and 2-year follow-ups. The large discrepancy between at least moderate regional reported pain but a negative provocative examination warrants further investigation as to the source of substantial pain in nearly one-quarter of ASD patients postoperatively.

STUDY DESIGN/METHODS:Retrospective analysis of retrospectively collected data. OBJECTIVE:To determine the effects of preoperative nonsteroidal anti-inflammatory drug (NSAID) use on estimated blood loss (EBL) and postoperative drain output in TLIF procedures. SUMMARY OF BACKGROUND DATA/BACKGROUND:Current standards of care recommend patients prescribed NSAIDs for chronic lower back pain discontinue NSAIDs at least 1 week before spine fusion surgery. The literature surrounding the effects of preoperative NSAID use is unclear, however, with dissonant findings regarding postoperative blood loss and complications. METHODS:A retrospective case review was performed on 429 cases of 1-level or 2-level TLIF, with patient NSAID use recorded within 3 days of surgery, at a single institution. Linear and logistic regressions were used to assess associations between NSAID use, patient and surgical characteristics, EBL, and drain output. RESULTS:NSAID use was significantly positively associated with drain output (P=0.03), with an approximate increase of 21±9.7 mL/day but no significant association with any postoperative complications (P=0.77). Drain output also had significant, independent positive associations with patient age (P=0.007), male sex (P<0.001), and a number of levels fused (P<0.001), and significant negative associations with robot-assisted (P<0.001) and minimally invasive (P=0.04) procedures. No significant association was detected between NSAID use and EBL (P=0.21), though EBL had significant positive associations with operative time (P<0.001) and levels fused (P<0.001), and multiple NSAIDs had a significant positive association with EBL (P<0.001). CONCLUSIONS:NSAID use had a statistically significant, but small, effect on drain output and no detectable effect on postoperative complications within 3 days of TLIF procedures, suggesting most patients can safely continue NSAID use up until their date of surgery. Future studies should further delineate the effects of preoperative NSAID use, such that a more refined risk profile could be developed from patient and surgical characteristics and NSAID use information.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Thoracolumbar spinal deformity frequently coexists with cervical spine deformity (CD) and lower extremity osteoarthritis (OA), complicating management and compounding functional disability. This study investigates the additive burden of these conditions on patient-reported outcome measures (PROMs). METHODS:This retrospective analysis assessed primary thoracolumbar deformity patients undergoing corrective surgery. Demographics, spinopelvic alignment, and PROMs were characterized. Severe CD was defined by ≥1 Ames criterion. Hip (HOA) and knee (KOA) OA were defined as Kellgren-Lawrence grade ≥3. Hierarchical regression and mixed-effects models evaluated the incremental and longitudinal impacts of these conditions on PROMs. RESULTS:Among 816 patients (mean age 60.4 years, 67.1% female), 24.8% had CD, 43.7% HOA, and 40.4% KOA at baseline. Regression revealed that HOA worsened Oswestry Disability Index (ODI) total (R2 = 0.056, P = .008), ODI Walking (R2 = 0.121, P <.001), Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (R2 = 0.108, P = .013), and Veterans RAND 12-Item Health Survey (VR-12) Physical Component Score (PCS) (R2 = 0.098, P = .022). KOA primarily affected pain and psychosocial outcomes, including ODI Pain (R2 = 0.033, P = .001), PROMIS Depression (R2 = 0.018, P = .002), Scoliosis Research Society-22 Mental (R2 = 0.033, P = .004), and VR-12 Mental Component Score (R2 = 0.023, P = .025). CD contributed to ODI (R2 = 0.063, P = .018) and Scoliosis Research Society-22 Activity (R2 = 0.044, P = .032). Mixed-effects models showed improvements in all PROMs from baseline to 2-year follow-up (P <.001). However, HOA reduced improvements in ODI (3.41 points, P = .009), PROMIS Physical Function (1.37 points, P = .009), and VR-12 PCS (2.21 points, P = .003). KOA was associated with reduced walking tolerance (ODI Walking: 0.21 points, P = .020) and increased psychological burden (PROMIS Anxiety: 1.71 points, P = .007; VR-12 MCS: 2.01 points, P = .027). CD affected ODI Walking (0.51 points, P = .007) and VR-12 PCS (3.19 points, P = .043). CONCLUSION/CONCLUSIONS:HOA patients undergoing deformity correction have worse preoperative physical disability and impaired postoperative functional recovery. KOA is associated with greater psychological burden. Severe CD has smaller physical impact. These findings highlight the need for individualized, multidisciplinary management strategies, with particular emphasis on early identification and targeted intervention for hip pathology to optimize outcomes.

OBJECTIVE:While health-related quality of life (HRQOL) measures have been extensively quantified in cervical deformity (CD), this clinical dimension has not yet been fully integrated into understanding CD radiographic subtypes prior to surgery. The aim of this study was to identify distinct patterns of HRQOL deficits among patients with CD by focusing on clinical scores and to examine the association of these patterns with radiographic morphotypes of CD. METHODS:This was a retrospective analysis of a prospective multicenter database of patients with CD aged 18 years or older. Patient-reported outcome measures consisted of the Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA) scale, and Swallowing Quality of Life (SWAL-QOL) questionnaire. After performing a principal component analysis on the individual questions of the NDI, mJOA, and SWAL-QOL, 4 factors with eigenvalues > 1 were retained and included in a cluster analysis to assign patients into homogeneous groups of outcomes. Moreover, a subgroup of patients with severe deformity was described and analyzed. RESULTS:Overall, 134 patients (59% female, mean age ± SD 60.9 ± 10.8 years) were included in this analysis. The mean HRQOL scores were NDI, 49.1 ± 17.6; mJOA, 13.5 ± 2.7; and EQ-5D, 0.7 ± 0.1). The factor analysis involving NDI, SWAL-QOL, and mJOA revealed 4 clusters. Cluster A represented patients with a predominant sleep problem. Cluster B was patients with the lowest neck disability. Cluster C represented the most disabled patients in terms of dysphagia and neck disability. Cluster D represented patients with myelopathy. Among the 71 patients with severe deformity, the distribution of cervical morphotypes significantly differed across the 4 clusters of disability (p = 0.009). Cluster C mainly consisted of patients with cervicothoracic deformity (66.7%, p = 0.002). Cluster D had a large proportion of patients (66.7%) with focal deformity (p = 0.007). In clusters A and B, 57.9% and 46.4% of patients, respectively, presented with "flat neck" deformity (p = 0.02). CONCLUSIONS:Distinct patterns of HRQOL deficits were observed across a heterogeneous population of patients with CD, and these patterns were associated with specific radiographic morphotypes. These findings provide a framework for the next generation of CD classification, wherein HRQOL measures are combined with radiographic parameters.

STUDY DESIGN/METHODS:Retrospective cohort. OBJECTIVE:The ISSG-AO Spinal Deformity Complication Classification System (SDCCS) predicts Diagnosis Related Group (DRG) coding and cost. BACKGROUND:Inconsistent definitions of complications contribute to variation in reported surgical complication rates. Incorrect complication reporting can lead to over or under DRG reimbursement. The ISSG-AO SDCCS provides improved complication reporting reproducibility and may help predict complication costs. METHODS:ASD patients were grouped into: DRG without complication or comorbidity (CC) or Major CC (MCC) (DRGs 455 & 458), with CC (DRGs 454 & 457), and with MCC (DRGs 453 & 456). Complications were graded by intervention severity per ISSG-AO system: grade 0 (none), 1 (mild-e.g., med change), 2 (moderate-e.g., ICU), 3 (severe-e.g., reoperation). Cost were based on Medicare inpatient prospective payment system (IPSS, Medicare Allowable rate). A multinomial logistic model identified key predictors of DRG assignment by complication grades. RESULTS:Of the 675 patients, 14% were in DRGs without CC/MCC, 71% in DRGs with CC, and 15% were DRGs with MCC. Patients with complications requiring intervention mostly fell into the higher DRG categories (97%). Patients who received an intervention are approximately 6.75 (2.01-22.75, P<.0021) times more likely to be classified under DRG with CC and 15.72 (95% CI, 4.23-58.45, P<.0001) times more likely to be classified with DRG with MCC compared to those who did not receive an intervention. Each unit increase in Edmonton Frailty Score raises the odds of being in DRG with MCC by 1.24 (95% CI 1.04-1.48, P 0.017). Similar trends were seen for OR time and LOS. Reimbursement showed incremental increase from $49.5K to $56K to $70K across DRG categories. CONCLUSIONS:Patients with elevated ISSG-AO scores are more likely to be categorized into higher DRGs, experience extended lengths of stay and generate greater healthcare expenditures. The ISSG-AO SDCCS predicts DRG thereby helping standardize complication reporting.

PURPOSE/OBJECTIVE:Vertebral body tethering (VBT) offers a fusion-less alternative for adolescent idiopathic scoliosis (AIS) patients, with tether breakage being a common concern, particularly in single-row VBT. Limited data exist on double-row VBT's impact on tether breakage. This study evaluates a two-row vertebral body tethering (2RVBT) technique, comparing cases with and without broken tethers in patients with over 2 year follow-up. METHODS:A single-center, retrospective review (2019-2022) included AIS patients who underwent mini-open thoracoscopic-assisted 2RVBT. Inclusion criteria were idiopathic scoliosis < 65° flexible curves, residual post-operative curves < 30°, and ≥ 2 year follow-up. Patients were divided into broken-tether (BT) and non-broken-tether (NBT) groups. Radiographic measures included thoracic (T) and thoracolumbar (TL) Cobb angles, coronal balance, L5 tilt, and sagittal parameters. Tether breakage was defined by > 5° change in screw angulation, with or without associated loss of correction. RESULTS:Among 109 patients (NBT = 94, BT = 15), the overall tether breakage rate was 13.7%. The BT group had significantly larger pre-operative TL Cobb angles (53.4 ± 14.0° vs 43.7 ± 13.8°, p = 0.02), greater TL correction (- 36.2 ± 9.1° vs -2 3.7 ± 15.9°, p = 0.002), and higher post-operative coronal imbalance (21.2 ± 14.6 mm vs 11.9 ± 9.4 mm, p = 0.049). They also had significantly lower skeletal maturity (mean Risser stage 2.0 ± 1.1 vs 3.2 ± 1.3, p = 0.019; Sanders 4.0 ± 1.5 vs 5.4 ± 2.0, p = 0.019). Most broken tethers did not require revision, but some cases underwent re-tethering or fusion. CONCLUSION/CONCLUSIONS:Double tether constructs may reduce the rate of tether breakage following VBT. The main risk factors for tether breakage following double tether VBT are residual post-operative coronal imbalance, larger corrections in the lumbar spine, large rigid thoracic curves, and skeletal immaturity. Furthermore, most broken tethers did not require revision, which may indicate that curves maintained appropriate correction post-breakage due to the functional lifespan of double tether constructs. Although these are preliminary findings that must be supported with further multicenter studies that include single-tether constructs, these findings should be taken into consideration when indicating patients for VBT.

This review analyzes enabling technology in Adult Spinal Deformity (ASD), with a focus on optimizing safety and teaching. The prevalence of ASD is rising, and recent technological advancements can empower surgeons to improve outcomes for ASD patients but also each comes with specific challenges. The paper highlights opportunities and potential obstacles in effective technology integration and assesses key enabling technologies, including surgical planning software, machine leaning, three-dimensional printing, augmented and virtual reality, patient-specific instrumentation as well as navigation and robotics.

OBJECTIVE:The aim of this study was to determine if there are any specific procedural, demographic, and/or radiographic factors that are associated with an improved postoperative lower extremity (LE) motor score (LEMS) among patients with adult spinal deformity (ASD) and abnormal baseline LEMS undergoing surgical correction. METHODS:Patients with ASD enrolled in an observational prospective study from 2018 to 2023 at 13 spinal deformity centers in North America were queried. Eligible participants met at least one of the following radiographic and/or procedural inclusion criteria: pelvic incidence minus lumbar lordosis mismatch ≥ 25°, T1 pelvic angle ≥ 30°, SVA ≥ 15 cm, thoracic scoliosis ≥ 70°, thoracolumbar scoliosis ≥ 50°, global coronal malalignment ≥ 7 cm, underwent 3-column osteotomy (3CO), spinal fusion ≥ 12 levels, and/or age ≥ 65 years with ≥ 7 levels of instrumentation. Patients with a baseline abnormal LEMS were dichotomized based on whether the LEMS improved or deteriorated from baseline by the 6-week postoperative visit. Patients with a maintained LEMS by 6 weeks compared with baseline were excluded. Patient and operative characteristics were compared through bivariate analyses to assess differences in treatment. A multivariable logistic regression model was built to discern independent factors associated with improved LEMS while controlling for potential confounders. RESULTS:Of 121 patients (77 female, mean age 62.9 years) included in the study, 109 (90.1%) improved and 12 (9.9%) experienced further deterioration from baseline to 6 weeks. Both groups had similar baseline LEMS by laterality and per nerve root. The groups were similar in age, sex, comorbidities, baseline LEMS, BMI, surgical indication, number of instrumented levels, estimated blood loss, operating room time, and hospital length of stay (p > 0.05). No differences in radiographic parameters at baseline and 6 weeks were observed aside from patients whose score had deteriorated experiencing greater change in the L1 pelvic angle (∆L1PA) (-8.0° ± 8.3° vs -1.6° ± 7.6°, p = 0.0413). Despite having similar frequencies of lumbar decompressions performed across a similar number of levels, patients whose conditions had deteriorated at 6 weeks had fewer lumbar posterior column osteotomies (PCOs) performed (50% vs 82.6%, p = 0.0169). No differences in in the frequency and number of 3COs performed were observed. Patients whose score had deteriorated experienced greater intraoperative neurophysiological monitoring (IONM) changes (41.7% vs 8.3%, p = 0.0050), all of which were motor deficits. Controlling for ∆L1PA and IONM changes revealed lumbar PCOs to be an independent driver of improved LEMS (OR 4.99 [95% CI 1.05-23.70]), with excellent model performance (p = 0.0031, area under the receiver operating characteristic curve of 0.77, Hosmer-Lemeshow goodness-of-fit test p = 0.3017). CONCLUSIONS:Performing lumbar decompressions alone might not be enough to improve LE weakness in patients with ASD and preoperative motor impairment, while the use of PCO was beneficial for improvement. Thus, more aggressive and thorough decompressions afforded by a combined approach of lumbar PCOs and decompression should be considered in this patient population to optimize postoperative motor strength.

STUDY DESIGN/METHODS:Single-center retrospective study. OBJECTIVE:To evaluate the risks associated with postoperative kyphosis and loss of range of motion after cervical disc replacement (CDR). SUMMARY OF BACKGROUND DATA/BACKGROUND:One of the main benefits of CDR is that it maintains physiological range of motion (ROM) and lordosis while achieving decompression. However, some patients experience loss in segmental ROM or postoperative segmental kyphosis. This study analyzes the radiographic outcomes of these patients. METHODS:Adult patients who underwent CDR were included. The cohort was divided into patients with poor x-ray outcomes (PXR) and successful x-ray outcomes (SXR). The PXR group was defined as patients who had a loss in segmental ROM (≥11 degress decrease in Δ segmental ROM) after CDR and/or postoperative segmental kyphosis at the operative level at 2-year follow-up. Sagittal alignment and other measures were compared. RESULTS:A total of 151 (PXR=47; SXR=104) patients met the inclusion criteria. Pre- and postoperative segmental lateral Cobb angles were more kyphotic in the PXR group (3.5 vs. -1.4 degress, P<0.001; 2.6 vs. -5.6 degress, P<0.001). There was a larger Δ in segmental lateral Cobb angle in the SXR group (-4.2 vs. -0.9 degress, P<0.001). The PXR group had more flexion and less extension (11.3 degress vs. 6.5 degress, P<0.001; -2.2 vs. -6.1 degress, P=0.049). Segmental ROM loss was significant in the PXR group (-5.7 degress vs. 1.5 degress, P<0.001). Pre- and postoperative C2-C7 lateral Cobb angles were more kyphotic in the PXR group (-1.2 vs. -9.4 degress, P<0.001; -2.9 vs. -13.9 degress, P<0.001). Pre- and postoperative cSVA were larger in the PXR group (29.6 vs. 25.3 mm, P=0.047; 30.1 vs. 22.8 mm, P=0.004). Multiple variable regressions showed higher preoperative segmental lateral Cobb angle increased odds of SXR (OR=1.217, 95% CI: 1.083-1.369, P<0.001), while larger preoperative C2-C7 ROM decreased them (OR=0.970, 95% CI: 0.994-0.996, P=0.024). No significant differences in postoperative complications were observed. CONCLUSIONS:Patients with postoperative kyphosis or loss of ROM were more likely to have less segmental and regional C2-7 lordosis and a larger cSVA. Surgeons should consider these preoperative parameters when indicating CDR and counseling patients.