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Francis Lovecchio, Jeffrey G. Stepan, Ajay Premkumar, Michael E. Steinhaus, Maria Sava, Peter Derman, Han Jo Kim and Todd Albert

OBJECTIVE

Patients with lumbar spine pathology are at high risk for opioid misuse. Standardizing prescribing practices through an institutional intervention may reduce the overprescribing of opiates, leading to a decrease in the risk for opioid misuse and the number of pills available for diversion. Without quantitative data on the “minimum necessary quantity” of opioids appropriate for postdischarge prescriptions, the optimal method for changing existing prescribing practices is unknown. The purpose of this study was to determine whether mandatory provider education and prescribing guidelines could modify prescriber behavior and lead to a decreased amount of opioids prescribed at hospital discharge following lumbar spine surgery.

METHODS

Qualified staff were required to attend a mandatory educational conference, and a consensus method among the spine service was used to publish qualitative prescribing guidelines. Prescription data for 2479 patients who had undergone lumbar spine surgery were captured and compared based on the timing of surgery. The preintervention group consisted of 1177 patients who had undergone spine surgery in the period before prescriber education and guidelines (March 1, 2016–November 1, 2016). The postintervention group consisted of 1302 patients who had undergone spine surgery after the dissemination of the guidelines (February 1, 2017–October 1, 2017). Surgeries were classified as decompression or fusion procedures. Patients who had undergone surgeries for infection and patients on long-acting opioids were excluded.

RESULTS

For all lumbar spine surgeries (decompression and fusion), the mean amount of opioids prescribed at discharge was lower after the educational program and distribution of prescribing guidelines (629 ± 294 oral morphine equivalent [OME] preintervention vs 490 ± 245 OME postintervention, p < 0.001). The mean number of prescribed pills also decreased (81 ± 26 vs 66 ± 22, p < 0.001). Prescriptions for 81 or more tablets dropped from 65.5% to 25.5%. Tramadol was prescribed more frequently after prescriber education (9.9% vs 18.6%, p < 0.001). Refill rates within 6 weeks were higher after the institutional intervention (7.6% vs 12.4%, p < 0.07).

CONCLUSIONS

Qualitative guidelines and prescriber education are effective in reducing the amount of opioids prescribed at discharge and encouraging the use of weaker opioids. Coupling provider education with prescribing guidelines is likely synergistic in achieving larger reductions. The sustainability of these changes is yet to be determined.

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Michael P. Kelly, Michael A. Kallen, Christopher I. Shaffrey, Justin S. Smith, Douglas C. Burton, Christopher P. Ames, Virginie Lafage, Frank J. Schwab, Han Jo Kim, Eric O. Klineberg, Shay Bess and the International Spine Study Group

OBJECTIVE

After using PROsetta Stone crosswalk tables to calculate Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) scores, the authors sought to examine 1) correlations with Scoliosis Research Society–22r (SRS-22r) scores, 2) responsiveness to change, and 3) the relationship between baseline scores and 2-year follow-up scores in adult spinal deformity (ASD).

METHODS

PROsetta Stone crosswalk tables were used to converted SF-36 scores to PROMIS scores for pain and physical function in a cohort of ASD patients with 2-year follow-up. Spearman correlations were used to evaluate the relationship of PROMIS scores with SRS-22r scores. Effect size (ES) and adjusted standardized response mean (aSRM) were used to assess responsiveness to change. Linear regression was used to evaluate the association between baseline scores and 2-year follow-up scores.

RESULTS

In total, 425 (425/625, 68%) patients met inclusion criteria. Strong correlations (all |r| > 0.7, p < 0.001) were found between baseline and 2-year PROMIS values and corresponding SRS-22r domain scores. PROMIS-PI showed a large ES (1.09) and aSRM (0.88), indicating good responsiveness to change. PROMIS-PF showed a moderate ES (0.52) and moderate aSRM (0.69), indicating a moderate responsiveness to change. Patients with greater baseline pain complaints were associated with greater pain improvement at 2 years for both SRS-22r Pain (B = 0.39, p < 0.001) and PROMIS-PI (B = 0.45, p < 0.001). Higher functional scores at baseline were associated with greater average improvements in both SRS-22r Activity (B = 0.62, p < 0.001) and PROMIS-PF (B = 0.40, p < 0.001).

CONCLUSIONS

The authors found strong correlations between the SRS-22r Pain and Activity domains with corresponding PROMIS-PI and -PF scores. Pain measurements showed similar and strong ES and aSRM while the function measurements showed similar, moderate ES and aSRM at 2-year follow-up. These data support further exploration of the use of PROMIS–computer adaptive test instruments in ASD.

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Yong-Jun Cho, Chi Hern Lee, Dae Won Kim, Ki-Yeon Yoo, Won Sik Eum, Min Jea Shin, Hyo Sang Jo, Jinseu Park, Kyu Hyung Han, Keun Wook Lee and Soo Young Choi

The authors investigated the effects of a silk solution against laminectomy-induced dural adhesion formation and inflammation in a rat model. They found that it significantly reduced postlaminectomy dural adhesion formation and inflammation. Dural adhesion formation, thought to be an inevitable consequence of laminectomy, is one of the most common complications following spinal surgery, and the authors' results indicate that the silk solution might be a potential novel therapeutic agent for dural adhesion formation.

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Renaud Lafage, Ibrahim Obeid, Barthelemy Liabaud, Shay Bess, Douglas Burton, Justin S. Smith, Cyrus Jalai, Richard Hostin, Christopher I. Shaffrey, Christopher Ames, Han Jo Kim, Eric Klineberg, Frank Schwab, Virginie Lafage and the International Spine Study Group

OBJECTIVE

The surgical correction of adult spinal deformity (ASD) often involves modifying lumbar lordosis (LL) to restore ideal sagittal alignment. However, corrections that include large changes in LL increase the risk for development of proximal junctional kyphosis (PJK). Little is known about the impact of cranial versus caudal correction in the lumbar spine on the occurrence of PJK. The goal of this study was to investigate the impact of the location of the correction on acute PJK development.

METHODS

This study was a retrospective review of a prospective multicenter database. Surgically treated ASD patients with early follow-up evaluations (6 weeks) and fusions of the full lumbosacral spine were included. Radiographic parameters analyzed included the classic spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], PI−LL, and sagittal vertical axis [SVA]) and segmental correction. Using Glattes’ criteria, patients were stratified into PJK and noPJK groups and propensity matched by age and regional lumbar correction (ΔPI−LL). Radiographic parameters and segmental correction were compared between PJK and noPJK patients using independent t-tests.

RESULTS

After propensity matching, 312 of 483 patients were included in the analysis (mean age 64 years, 76% women, 40% with PJK). There were no significant differences between PJK and noPJK patients at baseline or postoperatively, or between changes in alignment, with the exception of thoracic kyphosis (TK) and ΔTK. PJK patients had a decrease in segmental lordosis at L4-L5-S1 (−0.6° vs 1.6°, p = 0.025), and larger increases in segmental correction at cranial levels L1-L2-L3 (9.9° vs 7.1°), T12-L1-L2 (7.3° vs 5.4°), and T11-T12-L1 (2.9° vs 0.7°) (all p < 0.05).

CONCLUSIONS

Although achievement of an optimal sagittal alignment is the goal of realignment surgery, dramatic lumbar corrections appear to increase the risk of PJK. This study was the first to demonstrate that patients who developed PJK underwent kyphotic changes in the L4–S1 segments while restoring LL at more cranial levels (T12–L3). These findings suggest that restoring lordosis at lower lumbar levels may result in a decreased risk of developing PJK.

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Blake N. Staub, Renaud Lafage, Han Jo Kim, Christopher I. Shaffrey, Gregory M. Mundis Jr., Richard Hostin, Douglas Burton, Lawrence Lenke, Munish C. Gupta, Christopher Ames, Eric Klineberg, Shay Bess, Frank Schwab, Virginie Lafage and the International Spine Study Group

OBJECTIVE

Numerous studies have attempted to delineate the normative value for T1S−CL (T1 slope minus cervical lordosis) as a marker for both cervical deformity and a goal for correction similar to how PI-LL (pelvic incidence–lumbar lordosis) mismatch informs decision making in thoracolumbar adult spinal deformity (ASD). The goal of this study was to define the relationship between T1 slope (T1S) and cervical lordosis (CL).

METHODS

This is a retrospective review of a prospective database. Surgical ASD cases were initially analyzed. Analysis across the sagittal parameters was performed. Linear regression analysis based on T1S was used to provide a clinically applicable equation to predict CL. Findings were validated using the postoperative alignment of the ASD patients. Further validation was then performed using a second, normative database. The range of normal alignment associated with horizontal gaze was derived from a multilinear regression on data from asymptomatic patients.

RESULTS

A total of 103 patients (mean age 54.7 years) were included. Analysis revealed a strong correlation between T1S and C0–7 lordosis (r = 0.886), C2–7 lordosis (r = 0.815), and C0–2 lordosis (r = 0.732). There was no significant correlation between T1S and T1S−CL. Linear regression analysis revealed that T1S−CL assumed a constant value of 16.5° (R2 = 0.664, standard error 2°). These findings were validated on the postoperative imaging (mean absolute error [MAE] 5.9°). The equation was then applied to the normative database (MAE 6.7° controlling for McGregor slope [MGS] between −5° and 15°). A multilinear regression between C2–7, T1S, and MGS demonstrated a range of T1S−CL between 14.5° and 26.5° was necessary to maintain horizontal gaze.

CONCLUSIONS

Normative CL can be predicted via the formula CL = T1S − 16.5° ± 2°. This implies a threshold of deformity and aids in providing a goal for surgical correction. Just as pelvic incidence (PI) can be used to determine the ideal LL, T1S can be used to predict ideal CL. This formula also implies that a kyphotic cervical alignment is to be expected for individuals with a T1S < 16.5°.

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Han Jo Kim, Sohrab Virk, Jonathan Elysee, Peter Passias, Christopher Ames, Christopher I. Shaffrey, Gregory Mundis Jr., Themistocles Protopsaltis, Munish Gupta, Eric Klineberg, Justin S. Smith, Douglas Burton, Frank Schwab, Virginie Lafage, Renaud Lafage and the International Spine Study Group

OBJECTIVE

Cervical deformity (CD) is difficult to define due to the high variability in normal cervical alignment based on postural- and thoracolumbar-driven changes to cervical alignment. The purpose of this study was to identify whether patterns of sagittal deformity could be established based on neutral and dynamic alignment, as shown on radiographs.

METHODS

This study is a retrospective review of a prospective, multicenter database of CD patients who underwent surgery from 2013 to 2015. Their radiographs were reviewed by 12 individuals using a consensus-based method to identify severe sagittal CD. Radiographic parameters correlating with health-related quality of life were introduced in a two-step cluster analysis (a combination of hierarchical cluster and k-means cluster) to identify patterns of sagittal deformity. A comparison of lateral and lateral extension radiographs between clusters was performed using an ANOVA in a post hoc analysis.

RESULTS

Overall, 75 patients were identified as having severe CD due to sagittal malalignment, and they formed the basis of this study. Their mean age was 64 years, their body mass index was 29 kg/m2, and 66% were female. There were significant correlations between focal alignment/flexibility of maximum kyphosis, cervical lordosis, and thoracic slope minus cervical lordosis (TS-CL) flexibility (r = 0.27, 0.31, and −0.36, respectively). Cluster analysis revealed 3 distinct groups based on alignment and flexibility. Group 1 (a pattern involving a flat neck with lack of compensation) had a large TS-CL mismatch despite flexibility in cervical lordosis; group 2 (a pattern involving focal deformity) had focal kyphosis between 2 adjacent levels but no large regional cervical kyphosis under the setting of a low T1 slope (T1S); and group 3 (a pattern involving a cervicothoracic deformity) had a very large T1S with a compensatory hyperlordosis of the cervical spine.

CONCLUSIONS

Three distinct patterns of CD were identified in this cohort: flat neck, focal deformity, and cervicothoracic deformity. One key element to understanding the difference between these groups was the alignment seen on extension radiographs. This information is a first step in developing a classification system that can guide the surgical treatment for CD and the choice of fusion level.

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Themistocles S. Protopsaltis, Justin K. Scheer, Jamie S. Terran, Justin S. Smith, D. Kojo Hamilton, Han Jo Kim, Greg M. Mundis Jr., Robert A. Hart, Ian M. McCarthy, Eric Klineberg, Virginie Lafage, Shay Bess, Frank Schwab, Christopher I. Shaffrey, Christopher P. Ames and International Spine Study Group

OBJECT

Regional cervical sagittal alignment (C2–7 sagittal vertical axis [SVA]) has been shown to correlate with health-related quality of life (HRQOL). The study objective was to examine the relationship between cervical and thoracolumbar alignment parameters with HRQOL among patients with operative and nonoperative adult thoracolumbar deformity.

METHODS

This is a multicenter prospective data collection of consecutive patients with adult thoracolumbar spinal deformity. Clinical measures of disability included the Oswestry Disability Index (ODI), Scoliosis Research Society-22 Patient Questionnaire (SRS-22), and 36-Item Short-Form Health Survey (SF-36). Cervical radiographic parameters were correlated with global sagittal parameters within the nonoperative and operative cohorts. A partial correlation analysis was performed controlling for C-7 SVA. The operative group was subanalyzed by the magnitude of global deformity (C-7 SVA ≥ 5 cm vs < 5 cm).

RESULTS

A total of 318 patients were included (186 operative and 132 nonoperative). The mean age was 55.4 ± 14.9 years. Operative patients had significantly worse baseline HRQOL and significantly larger C-7 SVA, pelvic tilt (PT), mismatch between pelvic incidence and lumbar lordosis (PI-LL), and C2-7 SVA. The operative patients with baseline C-7 SVA ≥ 5 cm had significantly larger C2-7 lordosis (CL), C2-7 SVA, C-7 SVA, PI-LL, and PT than patients with a normal C-7 SVA. For all patients, baseline C2-7 SVA and CL significantly correlated with baseline ODI, Physical Component Summary (PCS), SRS Activity domain, and SRS Appearance domain. Baseline C2-7 SVA also correlated with SRS Pain and SRS Total. For the operative patients with baseline C-7 SVA ≥ 5 cm, the 2-year C2-7 SVA significantly correlated with 2-year Mental Component Summary, SRS Mental, SRS Satisfaction, and decreases in ODI. Decreases in C2-7 SVA at 2 years significantly correlated with lower ODI at 2 years. Using partial correlations while controlling for C-7 SVA, the C2-7 SVA correlated significantly with baseline ODI (r = 0.211, p = 0.002), PCS (r = −0.178, p = 0.009), and SRS Activity (r = −0.145, p = 0.034) for the entire cohort. In the subset of operative patients with larger thoracolumbar deformities, the change in C2-7 SVA correlated with change in ODI (r = −0.311, p = 0.03).

CONCLUSIONS

Changes in cervical lordosis correlate to HRQOL improvements in thoracolumbar deformity patients at 2-year follow-up. Regional cervical sagittal parameters such as CL and C2–7 SVA are correlated with clinical measures of regional disability and health status in patients with adult thoracolumbar scoliosis. This effect may be direct or a reciprocal effect of the underlying global deformities on regional cervical alignment. However, the partial correlation analysis, controlling for the magnitude of the thoracolumbar deformity, suggests that there is a direct effect of cervical alignment on health measures. Improvements in regional cervical alignment postoperatively correlated positively with improved HRQOL.

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Justin K. Scheer, Peter G. Passias, Alexandra M. Sorocean, Anthony J. Boniello, Gregory M. Mundis Jr., Eric Klineberg, Han Jo Kim, Themistocles S. Protopsaltis, Munish Gupta, Shay Bess, Christopher I. Shaffrey, Frank Schwab, Virginie Lafage, Justin S. Smith, Christopher P. Ames and The International Spine Study Group

OBJECT

A high prevalence of cervical deformity (CD) has been identified among adult patients with thoracolumbar spinal deformity undergoing surgical treatment. The clinical impact of this is uncertain. This study aimed to quantify the differences in patient-reported outcomes among patients with adult spinal deformity (ASD) based on presence of CD prior to treatment.

METHODS

A retrospective review was conducted of a multicenter prospective database of patients with ASD who underwent surgical treatment with 2-year follow-up. Patients were grouped by the presence of preoperative CD: 1) cervical positive sagittal malalignment (CPSM) C2–7 sagittal vertical axis ≥ 4 cm; 2) cervical kyphosis (CK) C2–7 angle > 0; 3) CPSM and CK (BOTH); and 4) no baseline CD (NONE). Health-related quality of life (HRQOL) scores included the Physical Component Summary and Mental Component Summary (PCS and MCS) scores of the 36-Item Short Form Health Survey (SF-36), Oswestry Disability Index (ODI), Scoliosis Research Society-22 questionnaire (SRS-22), and minimum clinically important difference (MCID) of these scores at 2 years. Standard radiographic measurements were conducted for cervical, thoracic, and thoracolumbar parameters.

RESULTS

One hundred eighty-two patients were included in this study: CPSM, 45; CK, 37; BOTH, 16; and NONE, 84. Patients with preoperative CD and those without had similar baseline thoracolumbar radiographic measurements and similar correction rates at 2 years. Patients with and without preoperative CD had similar baseline HRQOL and on average both groups experienced some HRQOL improvement. However, those with preoperative CPSM had significantly worse postoperative ODI, PCS, SRS-22 Activity, SRS-22 Appearance, SRS-22 Pain, SRS-22 Satisfaction, and SRS-22 Total score, and were less likely to meet MCID for ODI, PCS, SRS-22 Activity, and SRS-22 Pain scores with the following ORs and 95% CIs: ODI 0.19 (0.07–0.58), PCS 0.17 (0.06–0.47), SRS-22 Activity 0.23 (0.09–0.62), SRS-22 Pain 0.20 (0.08–0.53), and SRS-22 Appearance 0.34 (0.12–0.94). Preoperative CK did not have an effect on outcomes. Interestingly, despite correction of the thoracolumbar deformity, 53.3% and 51.4% of patients had persistent CPSM and persistent CK, respectively.

CONCLUSIONS

Patients with thoracolumbar deformity without preoperative CD are likely to have greater improvements in HRQOL after surgery than patients with concomitant preoperative CD. Cervical positive sagittal alignment in adult patients with thoracolumbar deformity is strongly associated with inferior outcomes and failure to reach MCID at 2-year follow-up despite having similar baseline HRQOL to patients without CD. This was the first study to assess the impact of concomitant preoperative cervical malalignment in adult patients with thoracolumbar deformity. These results can help surgeons educate patients at risk for inferior outcomes and direct future research to identify an etiology and improve patient outcomes. Investigation into the etiology of the baseline cervical malalignment may be warranted in patients who present with thoracolumbar deformity.

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Michael P. Kelly, Lukas P. Zebala, Han Jo Kim, Daniel M. Sciubba, Justin S. Smith, Christopher I. Shaffrey, Shay Bess, Eric Klineberg, Gregory Mundis Jr., Douglas Burton, Robert Hart, Alex Soroceanu, Frank Schwab, Virginie Lafage and International Spine Study Group

OBJECT

The goal of this study was to examine the effectiveness of preoperative autologous blood donation (PABD) in adult spinal deformity (ASD) surgery.

METHODS

Patients undergoing single-stay ASD reconstructions were identified in a multicenter database. Patients were divided into groups according to PABD (either PABD or NoPABD). Propensity weighting was used to create matched cohorts of PABD and NoPABD patients. Allogeneic (ALLO) exposure, autologous (AUTO) wastage (unused AUTO), and complication rates were compared between groups.

RESULTS

Four hundred twenty-eight patients were identified as meeting eligibility criteria. Sixty patients were treated with PABD, of whom 50 were matched to 50 patients who were not treated with PABD (NoPABD). Nearly one-third of patients in the PABD group (18/60, 30%) did not receive any autologous transfusion and donated blood was wasted. In 6 of these cases (6/60, 10%), patients received ALLO blood transfusions without AUTO. In 9 cases (9/60, 15%), patients received ALLO and AUTO blood transfusions. Overall rates of transfusion of any type were similar between groups (PABD 70% [42/60], NoPABD 75% [275/368], p = 0.438). Major and minor in-hospital complications were similar between groups (Major PABD 10% [6/60], NoPABD 12% [43/368], p = 0.537; Minor PABD 30% [18/60], NoPABD 24% [87/368], p = 0.499). When controlling for potential confounders, PABD patients were more likely to receive some transfusion (OR 15.1, 95% CI 2.1-106.7). No relationship between PABD and ALLO blood exposure was observed, however, refuting the concept that PABD is protective against ALLO blood exposure. In the matched cohorts, PABD patients were more likely to sustain a major perioperative cardiac complication (PABD 8/50 [16%], NoPABD 1/50 [2%], p = 0.046). No differences in rates of infection or wound-healing complications were observed between cohorts.

CONCLUSIONS

Preoperative autologous blood donation was associated with a higher probability of perioperative transfusions of any type in patients with ASD. No protective effect of PABD against ALLO blood exposure was observed, and no risk of perioperative infectious complications was observed in patients exposed to ALLO blood only. The benefit of PABD in patients with ASD remains undefined.

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Christopher P. Ames, Justin S. Smith, Robert Eastlack, Donald J. Blaskiewicz, Christopher I. Shaffrey, Frank Schwab, Shay Bess, Han Jo Kim, Gregory M. Mundis Jr., Eric Klineberg, Munish Gupta, Michael O’Brien, Richard Hostin, Justin K. Scheer, Themistocles S. Protopsaltis, Kai-Ming G. Fu, Robert Hart, Todd J. Albert, K. Daniel Riew, Michael G. Fehlings, Vedat Deviren, Virginie Lafage and International Spine Study Group

OBJECT

Despite the complexity of cervical spine deformity (CSD) and its significant impact on patient quality of life, there exists no comprehensive classification system. The objective of this study was to develop a novel classification system based on a modified Delphi approach and to characterize the intra- and interobserver reliability of this classification.

METHODS

Based on an extensive literature review and a modified Delphi approach with an expert panel, a CSD classification system was generated. The classification system included a deformity descriptor and 5 modifiers that incorporated sagittal, regional, and global spinopelvic alignment and neurological status. The descriptors included: “C,” “CT,” and “T” for primary cervical kyphotic deformities with an apex in the cervical spine, cervicothoracic junction, or thoracic spine, respectively; “S” for primary coronal deformity with a coronal Cobb angle ≥ 15°; and “CVJ” for primary craniovertebral junction deformity. The modifiers included C2–7 sagittal vertical axis (SVA), horizontal gaze (chin-brow to vertical angle [CBVA]), T1 slope (TS) minus C2–7 lordosis (TS–CL), myelopathy (modified Japanese Orthopaedic Association [mJOA] scale score), and the Scoliosis Research Society (SRS)-Schwab classification for thoracolumbar deformity. Application of the classification system requires the following: 1) full-length standing posteroanterior (PA) and lateral spine radiographs that include the cervical spine and femoral heads; 2) standing PA and lateral cervical spine radiographs; 3) completed and scored mJOA questionnaire; and 4) a clinical photograph or radiograph that includes the skull for measurement of the CBVA. A series of 10 CSD cases, broadly representative of the classification system, were selected and sufficient radiographic and clinical history to enable classification were assembled. A panel of spinal deformity surgeons was queried to classify each case twice, with a minimum of 1 intervening week. Inter- and intrarater reliability measures were based on calculations of Fleiss k coefficient values.

RESULTS

Twenty spinal deformity surgeons participated in this study. Interrater reliability (Fleiss k coefficients) for the deformity descriptor rounds 1 and 2 were 0.489 and 0.280, respectively, and mean intrarater reliability was 0.584. For the modifiers, including the SRS-Schwab components, the interrater (round 1/round 2) and intrarater reliabilities (Fleiss k coefficients) were: C2–7 SVA (0.338/0.412, 0.584), horizontal gaze (0.779/0.430, 0.768), TS-CL (0.721/0.567, 0.720), myelopathy (0.602/0.477, 0.746), SRS-Schwab curve type (0.590/0.433, 0.564), pelvic incidence-lumbar lordosis (0.554/0.386, 0.826), pelvic tilt (0.714/0.627, 0.633), and C7-S1 SVA (0.071/0.064, 0.233), respectively. The parameter with the poorest reliability was the C7–S1 SVA, which may have resulted from differences in interpretation of positive and negative measurements.

CONCLUSIONS

The proposed classification provides a mechanism to assess CSD within the framework of global spinopelvic malalignment and clinically relevant parameters. The intra- and interobserver reliabilities suggest moderate agreement and serve as the basis for subsequent improvement and study of the proposed classification.