Three-Column Osteotomy for the Treatment of Rigid Cervical Deformity

Darryl Lau,Christopher P. Ames 대한척추신경외과학회 2020 Neurospine Vol.17 No.3

Adult cervical deformity (ACD) has been shown to have a substantial impact on quality of life and overall health, with moderate to severe deformities resulting in significant disability and dysfunction. Fortunately, surgical management and correction of cervical sagittal imbalance can offer significant benefits and improvement in pain and disability. ACD is a heterogenous disease and specific surgical correction strategies should reflect deformity type (driver of deformity) and patient-related factors. Spinal rigidity is one of the most important considerations as soft tissue releases and osteotomies play a crucial role in cervical deformity correction. For ankylosed, fixed, and severe deformity, 3-column osteotomy (3CO) is often warranted. A 3CO can be done through combined anteriorposterior (vertebral body resection) and posterior-only approaches (open or closed wedge pedicle subtraction osteotomies [PSOs]). This article reviews the literature for currently published studies that report results on the use of 3CO for ACD, with a special concentration on posterior based 3CO (open and closed wedge PSO). More specifically, this review discusses the indications, radiographic corrective ability, and associated complications.

Contribution of Lateral Interbody Fusion in Staged Correction of Adult Degenerative Scoliosis

Choi, Seung Won,Ames, Christopher,Berven, Sigurd,Chou, Dean,Tay, Bobby,Deviren, Vedat The Korean Neurosurgical Society 2018 Journal of Korean neurosurgical society Vol.61 No.6

Objective : Lateral interbody fusion (LIF) is attractive as a less invasive technique to address anterior spinal pathology in the treatment of adult spinal deformity. Its own uses and benefits in treatment of adult degenerative scoliosis are undefined. To investigate the radiographic and clinical outcomes of LIF, and staged LIF and posterior spinal fusion (PSF) for the treatment of adult degenerative scoliosis patients, we analyzed radiographic and clinical outcomes of adult degenerative scoliosis patients who underwent LIF and posterior spinal fusion. Methods : Forty consecutive adult degenerative scoliosis patients who underwent LIF followed by staged PSF at a single institution were retrospectively reviewed. Long-standing 36" anterior-posterior and lateral radiographs were taken preoperatively, at inter-stage, 3 months, 1 year, and 2 years after surgery were reviewed. Outcomes were assessed through the visual analogue scale (VAS), 36-Item Short Form Health Survey (SF-36), and Oswestry Disability Index (ODI). Results : Forty patients with a mean age of 66.3 (range, 49-79) met inclusion criteria. A mean of 3.8 levels (range, 2-5) were fused using LIF, while a mean of 9.0 levels (range, 3-16) were fused during the posterior approach. The mean time between stages was 1.4 days (range, 1-6). The mean follow-up was 19.6 months. Lumbar lordosis was significantly restored from $36.4^{\circ}$ preoperatively up to $48.9^{\circ}$ (71.4% of total correction) after LIF and $53.9^{\circ}$ after PSF. Lumbar coronal Cobb was prominently improved from $38.6^{\circ}$ preoperatively to $24.1^{\circ}$ (55.8% of total correction) after LIF, $12.6^{\circ}$ after PSF respectively. The mean pelvic incidence-lumbar lordosis mismatch was markedly improved from $22.2^{\circ}$ preoperatively to $8.1^{\circ}$ (86.5% of total correction) after LIF, $5.9^{\circ}$ after PSF. Correction of coronal imbalance and sagittal vertebral axis did not reach significance. The rate of perioperative complication was 37.5%. Five patients underwent revision surgery due to wound infection. No major perioperative medical complications occurred. At last follow-up, there were significant improvements in VAS, SF-36 Physical Component Summary and ODI scores. Conclusion : LIF provides significant corrections in the coronal and sagittal plane in the patients with adult degenerative scoliosis. However, LIF combined with staged PSF provides more excellent radiographic and clinical outcomes, with reduced perioperative risk in the treatment of adult degenerative scoliosis.

Commentary on Vertebral Body Sliding Osteotomy for Cervical Myelopathy With Rigid Kyphosis: A Technical Note

Michael M. Safaee,Christopher P. Ames 대한척추신경외과학회 2020 Neurospine Vol.17 No.3

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Diversity in Surgical Decision Strategies for Adult Spine Deformity Treatment: The Effects of Neurosurgery or Orthopedic Training Background and Surgical Experience

강지인,Naobumi Hosogane,Christopher Ames,Frank Schwab,Robert Hart,Douglas Burton,Christopher Shaffrey,Justin S. Smith,Shay Bess,조규정,하윤 대한척추신경외과학회 2018 Neurospine Vol.15 No.4

Objective: This study is aimed to investigate whether surgical strategies for adult spinal deformity (ASD) treatment differed among Korean physicians. Methods: This study is retrospective questionnaire-based study. ASD is challenging to manage, with a broad range of clinical and radiological presentations. To investigate possible nationality- or ethnicity-related differences in the surgical strategies adopted for ASD treatment, the International Spine Study Group surveyed physicians’ responses to 16 cases of ASD. We reviewed the answers to this survey from Korean physicians. Korean orthopedic surgeons (OS) and neurosurgeons (NS) received a questionnaire containing 16 cases and response forms via email. After reviewing the cases, physicians were asked to indicate whether they would treat each case with decompression or fusion. If fusion was chosen, physicians were also asked to indicate whether they would perform 3-column osteotomy. Retrospective chi-square analyses were performed to investigate whether the answers to each question differed according to training specialty or amount of surgical experience. Results: Twenty-nine physicians responded to our survey, of whom 12 were OS and 17 were NS. In addition, 18 (62.1%) had more than 10 years of experience in ASD correction and were assigned to the M10 group, while 11 (37.9%) had less than 10 years of experience and were assigned to the L10 group. We found that for all cases, the surgical strategies favored did not significantly differ between OS and NS or between the M10 and L10 groups. However, for both fusion surgery and 3-column osteotomy, opinions were divided regarding the necessity of the procedures in 4 of the 16 cases. Conclusion: The surgical strategies favored by physicians were similar for most cases regardless of their training specialty or experience. This suggests that these factors do not affect the surgical strategies selected for ASD treatment, with patient clinical and radiological characteristics having greater importance.

Sagittal Spinopelvic Malalignment in Parkinson Disease: Prevalence and Associations With Disease Severity

Oh, Jae Keun,Smith, Justin S.,Shaffrey, Christopher I.,Lafage, Virginie,Schwab, Frank,Ames, Christopher P.,Matsumoto, Morio,Baik, Jong Sam,Ha, Yoon by Lippincott Williams Wilkins 2014 1528-1159) Vol.39 No.14

STUDY DESIGN.: Prospective study. OBJECTIVE.: Our objectives were to evaluate the prevalence of sagittal spinopelvic malalignment in a consecutive series of patients with Parkinson disease (PD) and to identify factors associated with sagittal spinopelvic deformity in this population. SUMMARY OF BACKGROUND DATA.: PD is a degenerative neurological condition characterized by tremor, rigidity, bradykinesia, and loss of postural reflexes. The prevalence of spinal deformity in PD is higher than that of age-matched adults without PD. METHODS.: This study was a prospective assessment of consecutive patients with PD presenting to a neurology clinic during 12 months. Inclusion criteria included age more than 21 years and diagnosis of PD. Age- and sex-matched control group was selected from patients with cervical spondylosis. Clinical and demographic factors were collected including Unified Parkinson Disease Rating Scale score and Hoehn and Yahr stage. Full-length standing spine radiographs were assessed. Patients were grouped into either low C7 sagittal vertical axis (SVA) (<5 cm) or high C7 SVA (≥5 cm) and into matched (≤10°) or mismatched (>10°) pelvic incidence (PI)-lumbar lordosis. RESULTS.: Eighty-nine patients met criteria (41 males/48 females), including 52 with low C7 SVA and 37 with high C7 SVA. Significantly higher prevalence of high C7 SVA was found in PD (41.6 vs. 16.8%; P < 0.001). The high C7 SVA group was significantly older (72.4 vs. 65.1 yr; P < 0.001) and had a higher proportion of females (68% vs. 44%; P = 0.034), greater severity of PD based on Hoehn and Yahr stage (1.89 vs. 1.37; P < 0.001) and Unified Parkinson Disease Rating Scale (30.5 vs. 17.2; P = 0.002. Unified Parkinson Disease Rating Scale significantly correlated with C7 SVA (r = 0.474). Compared with the matched (≤10°) PI-lumbar lordosis group, the mismatch PI-lumbar lordosis group had higher C7 SVA, higher PI, higher pelvic tilt, lower lumbar lordosis, and lower thoracic kyphosis (P ≤ 0.003). CONCLUSION.: Patients with PD have a high prevalence of sagittal spinopelvic malalignment than control group patients. Greater severity of PD is associated with sagittal spinopelvic malalignment.Level of Evidence: 3

Prevalence and type of cervical deformities among adults with Parkinson's disease: a cross-sectional study

Moon, Bong Ju,Smith, Justin S.,Ames, Christopher P.,Shaffrey, Christopher I.,Lafage, Virginie,Schwab, Frank,Matsumoto, Morio,Baik, Jong Sam,Ha, Yoon Journal of Neurosurgery Publishing Group 2016 Journal of Neurosurgery: Spine Vol.24 No.4

<B>OBJECT</B><P>To identify the characteristics of cervical deformities in Parkinson's disease (PD) and the role of severity of PD in the development of cervical spine deformities, the authors investigated the prevalence of the cervical deformities, cervical kyphosis (CK), and cervical positive sagittal malalignment (CPSM) in patients with PD. They also analyzed the association of severity of cervical deformities with the stage of PD in the context of global sagittal spinopelvic alignment.</P><B>METHODS</B><P>This study was a prospective assessment of consecutively treated patients (n = 89) with PD. A control group of the age- and sex-matched patients was selected from patients with degenerative cervical spine disease but without PD. Clinical and demographic parameters including age, sex, duration of PD, and Hoehn and Yahr (H&Y) stage were collected. Full-length standing radiographs were used to assess spinopelvic parameters. CK was defined as a C2-7 Cobb angle < 0°. CPSM was defined as C2-7 sagittal vertical axis (SVA) > 4 cm.</P><B>RESULTS</B><P>A significantly higher prevalence of CPSM (28% vs 1.1%, p < 0.001), but not CK (12% vs 10.1%, p = 0.635), was found in PD patients compared with control patients. Among patients with PD, those with CK were younger (62.1 vs 69.0 years, p = 0.013) and had longer duration of PD (56.4 vs 36.2 months, p = 0.034), but the severity of PD was not significantly different. Logistic regression analysis revealed that the presence of CK was associated with younger age, higher mismatch between pelvic incidence and lumbar lordosis, and lower C7-S1 SVA. The patients with CPSM had significantly greater thoracic kyphosis (TK) (p < 0.001) and a trend toward more advanced H&Y stage (p = 0.05). Logistic regression analysis revealed that CPSM was associated with male sex, greater TK, and more advanced H&Y stage.</P><B>CONCLUSIONS</B><P>Patients with PD have a significantly higher prevalence of CPSM compared with age- and sex-matched control patients with cervical degenerative disease but without PD. Among patients with PD, CK is not associated with the severity of PD but is associated with overall global sagittal malalignment. In contrast, the presence of CPSM is associated more with the severity of PD than it is with the presence of global sagittal malalignment. Collectively, these data suggest that the neuromuscular pathogenesis of PD may affect the development of CPSM more than of CK.</P>

Brief History of Spinal Neurosurgical Societies in the United States: Part 1

Sasha Vaziri,Daniel K. Resnick,Christopher P. Ames,James S. Harrop,Christopher I. Shaffrey,Kern Singh,Justin S. Smith,Daniel J. Hoh 대한척추신경외과학회 2019 Neurospine Vol.16 No.4

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Artificial Intelligence and the Future of Spine Surgery

Rushikesh S. Joshi,Darryl Lau,Christopher P. Ames 대한척추신경외과학회 2019 Neurospine Vol.16 No.4

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Is Sacral Extension a Risk Factor for Early Proximal Junctional Kyphosis in Adult Spinal Deformity Surgery?

Sebastian Decker,Renaud Lafage,Christian Krettek,Robert Hart,Christopher Ames,Justin S. Smith,Douglas Burton,Eric Klineberg,Shay Bess,Frank J. Schwab,Virginie Lafage,International Spine Study Group 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.2

Study Design: Retrospective cohort study. Purpose: To investigate the role of sacral extension (SE) for the development of proximal junctional kyphosis (PJK) in adult spinal deformity (ASD) surgery. Overview of Literature: The development of PJK is multifactorial and different risk factors have been identified. Of these, there is some evidence that SE also affects the development of PJK, but data are insufficient. Methods: Using a combined database comprising two propensity-matched groups of fusions following ASD surgery, one with fixation to S1 or S1 and the ilium (SE) and one without SE but with a lower instrumented vertebra of L5 or higher (lumbar fixation, LF), PJK and the role of further parameters were analyzed. The propensity-matched variables included age, the upper-most instrumented vertebra (UIV), preoperative sagittal alignment, and the baseline to 1 year change of the sagittal alignment. Results: Propensity matching led to two groups of 89 patients each. The UIV, pelvic incidence minus lumbar lordosis, sagittal vertical axis, pelvic tilt, age, and body mass index were similar in both groups (p>0.05). The incidence of PJK at postoperative 1 year was similar for SE (30.3%) and LF (22.5%) groups (p=0.207). The PJK angle was comparable (p=0.963) with a change of −8.2° (SE) and −8.3° (LF) from the preoperative measures (p=0.954). A higher rate of PJK after SE (p=0.026) was found only in the subgroup of patients with UIV levels between T9 and T12. Conclusions: Instrumentation to the sacrum with or without iliac extension did not increase the overall risk of PJK. However, an increased risk for PJK was found after SE with UIV levels between T9 and T12.

Artificial Intelligence for Adult Spinal Deformity

Rushikesh S. Joshi,Alexander F. Haddad,Darryl Lau,Christopher P. Ames 대한척추신경외과학회 2019 Neurospine Vol.16 No.4

Adult spinal deformity (ASD) is a complex disease that significantly affects the lives of many patients. Surgical correction has proven to be effective in achieving improvement of spinopelvic parameters as well as improving quality of life (QoL) for these patients. However, given the relatively high complication risk associated with ASD correction, it is of paramount importance to develop robust prognostic tools for predicting risk profile and outcomes. Historically, statistical models such as linear and logistic regression models were used to identify preoperative factors associated with postoperative outcomes. While these tools were useful for looking at simple associations, they represent generalizations across large populations, with little applicability to individual patients. More recently, predictive analytics utilizing artificial intelligence (AI) through machine learning for comprehensive processing of large amounts of data have become available for surgeons to implement. The use of these computational techniques has given surgeons the ability to leverage far more accurate and individualized predictive tools to better inform individual patients regarding predicted outcomes after ASD correction surgery. Applications range from predicting QoL measures to predicting the risk of major complications, hospital readmission, and reoperation rates. In addition, AI has been used to create a novel classification system for ASD patients, which will help surgeons identify distinct patient subpopulations with unique risk-benefit profiles. Overall, these tools will help surgeons tailor their clinical practice to address patients’ individual needs and create an opportunity for personalized medicine within spine surgery.