scholarly journals Radiographic and Clinical Outcomes From the Use of S2 Alar Screws in Surgery for Adult Spinal Deformity

2018 ◽  
Vol 8 (7) ◽  
pp. 668-675
Author(s):  
Toshiyuki Nakazawa ◽  
Gen Inoue ◽  
Takayuki Imura ◽  
Masayuki Miyagi ◽  
Wataru Saito ◽  
...  
Keyword(s):  
Spinal Deformity ◽  
Thoracic Kyphosis ◽  
Pelvic Tilt ◽  
Pelvic Incidence ◽  
Adult Spinal Deformity ◽  
Vertical Axis ◽  
Mineral Density ◽  
Severe Osteoporosis ◽  
Sagittal Vertical Axis

Study Design: Retrospective. Objectives: To evaluate the efficacy of S2 alar screws in surgery for correction of adult spinal deformity (ASD). Methods: We retrospectively reviewed the cases of 23 patients (mean follow-up: 18.5 months, minimum 12 months) who underwent corrective surgery for ASD using S2 alar screws as anchors for instrumentation of lower vertebrae. The background of the patients and their spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], lumbar lordosis [LL], thoracic kyphosis [TK], sagittal vertical axis [SVA], and PI-LL) were evaluated. Results: LL was improved from 9.7 ± 20.5° and SVA from 141.0 ± 64.0 mm before surgery to 39.0 ± 9.6° and 51.7 ± 40.8 mm immediately after surgery, respectively, and 38.2 ± 12.7° and 70.5 ± 59.2 mm at final follow-up. In 13 patients without sufficient correction (postoperative PI-LL ≥10°), bone mineral density and postoperative LL were significantly less, and PI, PI-LL, and PT were significantly greater than in patients with postoperative PI-LL <10°, suggesting that these are risk factors for undercorrection. In 5 patients, SVA increased more than 40 mm during follow-up. Postoperative LL was significantly less (31.4° vs 41.0°) and postoperative PI-LL was significantly greater (21.6° vs 9.3°) in these patients, suggesting a PI-LL mismatch induces postoperative progression of global malalignment. Conclusions: Use of S2 alar screws as anchors for instrumentation in ASD surgery should be restricted. Their use might be an option for patients with low PI, and without severe osteoporosis, in whom efficient surgical correction can be obtained.

scholarly journals Association between bicortical screw fixation at upper instrumented vertebra and risk for upper instrumented vertebra fracture

2017 ◽  
Vol 26 (5) ◽  
pp. 638-644 ◽  
Author(s):  
Young-Seop Park ◽  
Seung-Jae Hyun ◽  
Ho Yong Choi ◽  
Ki-Jeong Kim ◽  
Tae-Ahn Jahng
Keyword(s):  
Spinal Deformity ◽  
Pelvic Incidence ◽  
Screw Fixation ◽  
Adult Spinal Deformity ◽  
Vertical Axis ◽  
Sagittal Vertical Axis ◽  
The Mean ◽  
Upper Instrumented Vertebra ◽  
Bicortical Screw

OBJECTIVEThe aim of this study was to investigate the risk of upper instrumented vertebra (UIV) fractures associated with UIV screw fixation (unicortical vs bicortical) and polymethylmethacrylate (PMMA) augmentation after adult spinal deformity surgery.METHODSA single-center, single-surgeon consecutive series of adult patients who underwent lumbar fusion for ≥ 4 levels (that is, the lower instrumented vertebra at the sacrum or pelvis and the UIV of the thoracolumbar spine [T9–L2]) were retrospectively reviewed. Age, sex, follow-up duration, sagittal UIV angle immediately postoperatively including several balance-related parameters (lumbar lordosis [LL], pelvic incidence, and sagittal vertical axis), bone mineral density, UIV screw fixation type, UIV PMMA augmentation, and UIV fracture were evaluated. Patients were divided into 3 groups: Group U, 15 patients with unicortical screw fixation at the UIV; Group P, 16 with bicortical screw fixation and PMMA augmentation at the UIV; and Group B, 21 with bicortical screw fixation without PMMA augmentation at the UIV.RESULTSThe mean number of levels fused was 6.5 ± 2.5, 7.5 ± 2.5, and 6.5 ± 2.5; the median age was 50 ± 29, 72 ± 6, and 59 ± 24 years; and the mean follow-up was 31.5 ± 23.5, 13 ± 6, and 24 ± 17.5 months in Groups U, P, and B, respectively (p > 0.05). There were no significant differences in balance-related parameters (LL, sagittal vertical axis, pelvic incidence–LL, and so on) among the groups. UIV fracture rates in Groups U (0%), P (31.3%), and B (42.9%) increased in sequence by group (p = 0.006). UIV bicortical screw fixation increased the risk for UIV fracture (OR 5.39; p = 0.02).CONCLUSIONSBicortical screw fixation at the UIV is a major risk factor for early UIV compression fracture, regardless of whether a thoracolumbosacral orthosis is used. To reduce the proximal junctional failure, unicortical screw fixation at the UIV is essential in adult spinal deformity correction surgery.

Patients with High Pelvic Tilt Achieve the Same Clinical Success as Those with Low Pelvic Tilt After Minimally Invasive Adult Deformity Surgery

Neurosurgery ◽  
2017 ◽  
Vol 83 (2) ◽  
pp. 270-276 ◽  
Author(s):  
Juan S Uribe ◽  
Jacob Januszewski ◽  
Michael Wang ◽  
Neel Anand ◽  
David O Okonkwo ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Spinal Deformity ◽  
Pelvic Tilt ◽  
Adult Spinal Deformity ◽  
Vertical Axis ◽  
Sagittal Vertical Axis ◽  
Adult Deformity ◽  
Radiographic Outcomes ◽  
Hrqol Data

Abstract BACKGROUND Pelvic tilt (PT) is a compensatory mechanism for adult spinal deformity patients to mitigate sagittal imbalance. The association between preop PT and postop clinical and radiographic outcomes has not been well studied in patients undergoing minimally invasive adult deformity surgery. OBJECTIVE To evaluate clinical and radiographic outcomes in adult spinal deformity patients with high and low preoperative PT treated surgically using less invasive techniques. METHODS Retrospective case-control, institutional review board-approved study. A multicenter, minimally invasive surgery spinal deformity patient database was queried for 2-yr follow-up with complete radiographic and health-related quality of life (HRQOL) data. Hybrid surgery patients were excluded. Inclusion criteria were as follows: age &gt; 18 and either coronal Cobb angle &gt; 20, sagittal vertical axis &gt; 5 cm, pelvic incidence-lumbar lordosis (PI-LL) &gt; 10 or PT &gt; 20. Patients were stratified by preop PT as per Schwab classification: low (PT&lt; 20), mid (PT 20-30), or high (&gt;30). Postoperative radiographic alignment parameters (PT, PI, LL, Cobb angle, sagittal vertical axis) and HRQOL data (Visual Analog Scale Back/Leg, Oswestry Disability Index) were evaluated and analyzed. RESULTS One hundred sixty-five patients had complete 2-yr outcomes data, and 64 patients met inclusion criteria (25 low, 21 mid, 18 high PT). High PT group had higher preop PI-LL mismatch (32.1 vs 4.7; P &lt; .001). At last follow-up, 76.5% of patients in the high PT group had continued PI-LL mismatch compared to 34.8% in the low PT group (P &lt; .006). There was a difference between groups in terms of postop changes of PT (–3.9 vs 1.9), LL (8.7 vs 0.5), and PI-LL (–9.5 vs 0.1). Postoperatively, HRQOL data (Oswestry Disability Index and Visual Analog Scale) were significantly improved in both groups (P &lt; .001). CONCLUSION Adult deformity patients with high preoperative PT treated with minimally invasive surgical techniques had less radiographic success but equivalent clinical outcomes as patients with low PT.

Reduced occurrence of primary rod fracture after adult spinal deformity surgery with accessory supplemental rods: retrospective analysis of 114 patients with minimum 2-year follow-up

2021 ◽  
pp. 1-12
Author(s):  
Emily P. Rabinovich ◽  
Thomas J. Buell ◽  
Tony R. Wang ◽  
Christopher I. Shaffrey ◽  
Justin S. Smith
Keyword(s):  
Retrospective Analysis ◽  
Spinal Deformity ◽  
Adult Spinal Deformity ◽  
Deformity Correction ◽  
Vertical Axis ◽  
Transforaminal Lumbar Interbody Fusion ◽  
Inclusion Criteria ◽  
Sagittal Vertical Axis ◽  
Rod Fracture

OBJECTIVE Rod fracture (RF) after adult spinal deformity (ASD) surgery is reported in approximately 6.8%–33% of patients and is associated with loss of deformity correction and higher reoperation rates. The authors’ objective was to determine the effect of accessory supplemental rod (ASR) placement on postoperative occurrence of primary RF after ASD surgery. METHODS This retrospective analysis examined patients who underwent ASD surgery between 2014 and 2017 by the senior authors. Inclusion criteria were age > 18 years, ≥ 5 instrumented levels including sacropelvic fixation, and diagnosis of ASD, which was defined as the presence of pelvic tilt ≥ 25°, sagittal vertical axis ≥ 5 cm, thoracic kyphosis ≥ 60°, coronal Cobb angle ≥ 20°, or pelvic incidence to lumbar lordosis mismatch ≥ 10°. The primary focus was patients with a minimum 2-year follow-up. RESULTS Of 148 patients who otherwise met the inclusion criteria, 114 (77.0%) achieved minimum 2-year follow-up and were included (68.4% were women, mean age 67.9 years, average body mass index 30.4 kg/m2). Sixty-two (54.4%) patients were treated with traditional dual-rod construct (DRC), and 52 (45.6%) were treated with ASR. Overall, the mean number of levels fused was 11.7, 79.8% of patients underwent Smith-Petersen osteotomy (SPO), 19.3% underwent pedicle subtraction osteotomy (PSO), and 66.7% underwent transforaminal lumbar interbody fusion (TLIF). Significantly more patients in the DRC cohort underwent SPO (88.7% of the DRC cohort vs 69.2% of the ASR cohort, p = 0.010) and TLIF (77.4% of the DRC cohort vs 53.8% of the ASR cohort, p = 0.0001). Patients treated with ASR had greater baseline sagittal malalignment (12.0 vs 8.6 cm, p = 0.014) than patients treated with DRC, and more patients in the ASR cohort underwent PSO (40.3% vs 1.6%, p < 0.0001). Among the 114 patients who completed follow-up, postoperative occurrence of RF was reported in 16 (14.0%) patients, with mean ± SD time to RF of 27.5 ± 11.8 months. There was significantly greater occurrence of RF among patients who underwent DRC compared with those who underwent ASR (21.0% vs 5.8%, p = 0.012) at comparable mean follow-up (38.4 vs 34.9 months, p = 0.072). Multivariate analysis demonstrated that ASR had a significant protective effect against RF (OR 0.231, 95% CI 0.051–0.770, p = 0.029). CONCLUSIONS This study demonstrated a statistically significant decrease in the occurrence of RF among ASD patients treated with ASR, despite greater baseline deformity and higher rate of PSO. These findings suggest that ASR placement may provide benefit to patients who undergo ASD surgery.

Characterizing Adult Cervical Deformity and Disability Based on Existing Cervical and Adult Deformity Classification Schemes at Presentation and Following Correction

Neurosurgery ◽  
2017 ◽  
Vol 82 (2) ◽  
pp. 192-201 ◽  
Author(s):  
Peter G Passias ◽  
Cyrus M Jalai ◽  
Justin S Smith ◽  
Virginie Lafage ◽  
Bassel G Diebo ◽  
...  
Keyword(s):  
Pelvic Tilt ◽  
Pelvic Incidence ◽  
Adult Spinal Deformity ◽  
Vertical Axis ◽  
Global Alignment ◽  
Sagittal Vertical Axis ◽  
Adult Deformity ◽  
Cervical Deformity ◽  
Curve Type ◽  
Horizontal Gaze

Abstract BACKGROUND Adult cervical deformity (ACD) classifications have not been implemented in a prospective ACD population and in conjunction with adult spinal deformity (ASD) classifications. OBJECTIVE To characterize cervical deformity type and malalignment with 2 classifications (Ames-ACD and Schwab-ASD). METHODS Retrospective review of a prospective multicenter ACD database. Inclusion: patients ≥18 yr with pre- and postoperative radiographs. Patients were classified with Ames-ACD and Schwab-ASD schemes. Ames-ACD descriptors (C = cervical, CT = cervicothoracic, T = thoracic, S = coronal, CVJ = craniovertebral) and alignment modifiers (cervical sagittal vertical axis [cSVA], T1 slope minus cervical lordosis [TS-CL], modified Japanese Ortphopaedic Association [mJOA] score, horizontal gaze) were assigned. Schwab-ASD curve type stratification and modifier grades were also designated. Deformity and alignment group distributions were compared with Pearson χ2/ANOVA. RESULTS Ames-ACD descriptors in 84 patients: C = 49 (58.3%), CT = 20 (23.8%), T = 9 (10.7%), S = 6 (7.1%). cSVA modifier grades differed in C, CT, and T deformities (P &lt; .019). In C, TS-CL grade prevalence differed (P = .031). Among Ames-ACD modifiers, high (1+2) cSVA grades differed across deformities (C = 47.7%, CT = 89.5%, T = 77.8%, S = 50.0%, P = .013). Schwab-ASD curve type and presence (n = 74, T = 2, L = 6, D = 2) differed significantly in S deformities (P &lt; .001). Higher Schwab-ASD pelvic incidence minus lumbar lordosis grades were less likely in Ames-ACD CT deformities (P = .027). Higher pelvic tilt grades were greater in high (1+2) cSVA (71.4% vs 36.0%, P = .015) and high (2+3) mJOA (24.0% vs 38.1%, P = .021) scores. Postoperatively, C and CT deformities had a trend toward lower cSVA grades, but only C deformities differed in TS-CL grade prevalence (0 = 31.3%, 1 = 12.2%, 2 = 56.1%, P = .007). CONCLUSION Cervical deformities displayed higher TS-CL grades and different cSVA grade distributions. Preoperative associations with global alignment modifiers and Ames-ACD descriptors were observed, though only cervical modifiers showed postoperative differences.

Asymmetrical pedicle subtraction osteotomy for correction of concurrent sagittal-coronal imbalance in adult spinal deformity: a comparative analysis

2020 ◽  
Vol 33 (6) ◽  
pp. 822-829
Author(s):  
Darryl Lau ◽  
Alexander F. Haddad ◽  
Vedat Deviren ◽  
Christopher P. Ames
Keyword(s):  
Spinal Deformity ◽  
Adult Spinal Deformity ◽  
Vertical Axis ◽  
Pedicle Subtraction Osteotomy ◽  
Sagittal Imbalance ◽  
Sagittal Vertical Axis ◽  
Coronal Imbalance ◽  
Significant Correction ◽  
Sagittal Deformity

OBJECTIVERigid multiplanar thoracolumbar adult spinal deformity (ASD) cases are challenging and many require a 3-column osteotomy (3CO), specifically asymmetrical pedicle subtraction osteotomy (APSO). The outcomes and additional risks of performing APSO for the correction of concurrent sagittal-coronal deformity have yet to be adequately studied.METHODSThe authors performed a retrospective review of all ASD patients who underwent 3CO during the period from 2006 to 2019. All cases involved either isolated sagittal deformity (patients underwent standard PSO) or concurrent sagittal-coronal deformity (coronal vertical axis [CVA] ≥ 4.0 cm; patients underwent APSO). Perioperative and 2-year follow-up outcomes were compared between patients with isolated sagittal imbalance who underwent PSO and those with concurrent sagittal-coronal imbalance who underwent APSO.RESULTSA total of 390 patients were included: 338 who underwent PSO and 52 who underwent APSO. The mean patient age was 64.6 years, and 65.1% of patients were female. APSO patients required significantly more fusions with upper instrumented vertebrae (UIV) in the upper thoracic spine (63.5% vs 43.3%, p = 0.007). Radiographically, APSO patients had greater deformity with more severe preoperative sagittal and coronal imbalance: sagittal vertical axis (SVA) 13.0 versus 10.7 cm (p = 0.042) and CVA 6.1 versus 1.2 cm (p < 0.001). In APSO cases, significant correction and normalization were achieved (SVA 13.0–3.1 cm, CVA 6.1–2.0 cm, lumbar lordosis [LL] 26.3°–49.4°, pelvic tilt [PT] 38.0°–20.4°, and scoliosis 25.0°–10.4°, p < 0.001). The overall perioperative complication rate was 34.9%. There were no significant differences between PSO and APSO patients in rates of complications (overall 33.7% vs 42.3%, p = 0.227; neurological 5.9% vs 3.9%, p = 0.547; medical 20.7% vs 25.0%, p = 0.482; and surgical 6.5% vs 11.5%, p = 0.191, respectively). However, the APSO group required significantly longer stays in the ICU (3.1 vs 2.3 days, p = 0.047) and hospital (10.8 vs 8.3 days, p = 0.002). At the 2-year follow-up, there were no significant differences in mechanical complications, including proximal junctional kyphosis (p = 0.352), pseudarthrosis (p = 0.980), rod fracture (p = 0.852), and reoperation (p = 0.600).CONCLUSIONSASD patients with significant coronal imbalance often have severe concurrent sagittal deformity. APSO is a powerful and effective technique to achieve multiplanar correction without higher risk of morbidity and complications compared with PSO for sagittal imbalance. However, APSO is associated with slightly longer ICU and hospital stays.

scholarly journals Clinical and radiographic parameters associated with best versus worst clinical outcomes in minimally invasive spinal deformity surgery

2016 ◽  
Vol 25 (1) ◽  
pp. 21-25 ◽  
Author(s):  
Khoi D. Than ◽  
Paul Park ◽  
Kai-Ming Fu ◽  
Stacie Nguyen ◽  
Michael Y. Wang ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Spinal Deformity ◽  
Pelvic Incidence ◽  
Sagittal Plane ◽  
Adult Spinal Deformity ◽  
Vertical Axis ◽  
Leg Pain ◽  
Sagittal Vertical Axis ◽  
Pain Scores ◽  
Spinal Deformity Surgery

OBJECTIVE Minimally invasive surgery (MIS) techniques are increasingly used to treat adult spinal deformity. However, standard minimally invasive spinal deformity techniques have a more limited ability to restore sagittal balance and match the pelvic incidence–lumbar lordosis (PI-LL) than traditional open surgery. This study sought to compare “best” versus “worst” outcomes of MIS to identify variables that may predispose patients to postoperative success. METHODS A retrospective review of minimally invasive spinal deformity surgery cases was performed to identify parameters in the 20% of patients who had the greatest improvement in Oswestry Disability Index (ODI) scores versus those in the 20% of patients who had the least improvement in ODI scores at 2 years' follow-up. RESULTS One hundred four patients met the inclusion criteria, and the top 20% of patients in terms of ODI improvement at 2 years (best group, 22 patients) were compared with the bottom 20% (worst group, 21 patients). There were no statistically significant differences in age, body mass index, pre- and postoperative Cobb angles, pelvic tilt, pelvic incidence, levels fused, operating room time, and blood loss between the best and worst groups. However, the mean preoperative ODI score was significantly higher (worse disability) at baseline in the group that had the greatest improvement in ODI score (58.2 vs 39.7, p < 0.001). There was no difference in preoperative PI-LL mismatch (12.8° best vs 19.5° worst, p = 0.298). The best group had significantly less postoperative sagittal vertical axis (SVA; 3.4 vs 6.9 cm, p = 0.043) and postoperative PI-LL mismatch (10.4° vs 19.4°, p = 0.027) than the worst group. The best group also had better postoperative visual analog scale back and leg pain scores (p = 0.001 and p = 0.046, respectively). CONCLUSIONS The authors recommend that spinal deformity surgeons using MIS techniques focus on correcting a patient's PI-LL mismatch to within 10° and restoring SVA to < 5 cm. Restoration of these parameters seems to impact which patients will attain the greatest degree of improvement in ODI outcomes, while the spines of patients who do the worst are not appropriately corrected and may be fused into a fixed sagittal plane deformity.

The utility of supine radiographs in the assessment of thoracic flexibility and risk of proximal junctional kyphosis

2021 ◽  
pp. 1-7
Author(s):  
Francis Lovecchio ◽  
Renaud Lafage ◽  
Jonathan Charles Elysee ◽  
Alex Huang ◽  
Bryan Ang ◽  
...  
Keyword(s):  
Thoracic Spine ◽  
Lumbar Lordosis ◽  
Pelvic Tilt ◽  
Pelvic Incidence ◽  
Vertical Axis ◽  
Control Analysis ◽  
Proximal Junctional Kyphosis ◽  
Sagittal Vertical Axis ◽  
Significant Difference ◽  
Junctional Kyphosis

OBJECTIVE Supine radiographs have successfully been used for preoperative planning of lumbar deformity corrections. However, they have not been used to assess thoracic flexibility, which has recently garnered attention as a potential contributor to proximal junctional kyphosis (PJK). The purpose of this study was to compare supine to standing radiographs to assess thoracic flexibility and to determine whether thoracic flexibility is associated with PJK. METHODS A retrospective study was conducted of a single-institution database of patients with adult spinal deformity (ASD). Sagittal alignment parameters were compared between standing and supine and between pre- and postoperative radiographs. Thoracic flexibility was determined as the change between preoperative standing thoracic kyphosis (TK) and preoperative supine TK, and these changes were measured over the overall thoracic spine and the fused portion of the thoracic spine (i.e., TK fused). A case-control analysis was performed to compare thoracic flexibility between patients with PJK and those without (no PJK). The cohort was also stratified into three groups based on thoracic flexibility: kyphotic change (increased TK), lordotic change (decreased TK), and no change. The PJK rate was compared between the cohorts. RESULTS A total of 101 patients (mean 63 years old, 82.2% female, mean BMI 27.4 kg/m2) were included. Preoperative Scoliosis Research Society–Schwab ASD classification showed moderate preoperative deformity (pelvic tilt 27.7% [score ++]; pelvic incidence–lumbar lordosis mismatch 44.6% [score ++]; sagittal vertical axis 42.6% [score ++]). Postoperatively, the average offset from age-adjusted alignment goals demonstrated slight overcorrection in the study sample (−8.5° ± 15.6° pelvic incidence–lumbar lordosis mismatch, −29.2 ± 53.1 mm sagittal vertical axis, −5.4 ± 10.8 pelvic tilt, and −7.6 ± 11.7 T1 pelvic angle). TK decreased between standing and supine radiographs and increased postoperatively (TK fused: −25.3° vs −19.6° vs −29.9°; all p < 0.001). The overall rate of radiographic PJK was 23.8%. Comparisons between PJK and no PJK demonstrated that offsets from age-adjusted alignment goals were similar (p > 0.05 for all). There was a significant difference in the PJK rate when stratified by thoracic flexibility cohorts (kyphotic: 0.0% vs no change: 18.4% vs lordotic: 35.0%; p = 0.049). Logistic regression revealed thoracic flexibility (p = 0.045) as the only independent correlate of PJK. CONCLUSIONS Half of patients with ASD experienced significant changes in TK during supine positioning, a quality that may influence surgical strategy. Increased thoracic flexibility is associated with PJK, possibly secondary to fusing the patient’s spine in a flattened position intraoperatively.

scholarly journals Normal Age-Adjusted Sagittal Spinal Alignment Is Achieved with Surgical Correction in Adolescent Idiopathic Scoliosis

2017 ◽  
Vol 11 (5) ◽  
pp. 770-779 ◽  
Author(s):  
Subaraman Ramchandran ◽  
Norah Foster ◽  
Akhila Sure ◽  
Thomas J. Errico ◽  
Aaron J. Buckland
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Lumbar Lordosis ◽  
Thoracic Kyphosis ◽  
Pelvic Incidence ◽  
Sagittal Alignment ◽  
Vertical Axis ◽  
Surgical Correction ◽  
Sagittal Vertical Axis

<sec><title>Study Design</title><p>Retrospective analysis.</p></sec><sec><title>Purpose</title><p>Our hypothesis is that the surgical correction of adolescent idiopathic scoliosis (AIS) maintains normal sagittal alignment as compared to age-matched normative adolescent population.</p></sec><sec><title>Overview of Literature</title><p>Sagittal spino-pelvic alignment in AIS has been reported, however, whether corrective spinal fusion surgery re-establishes normal alignment remains unverified.</p></sec><sec><title>Methods</title><p>Sagittal profiles and spino-pelvic parameters of thirty-eight postsurgical correction AIS patients ≤21 years old without prior fusion from a single institution database were compared to previously published normative age-matched data. Coronal and sagittal measurements including structural coronal Cobb angle, pelvic incidence, pelvic tilt, thoracic kyphosis, lumbar lordosis, sagittal vertical axis, C2–C7 cervical lordosis, C2–C7 sagittal vertical axis, and T1 pelvic angles were measured on standing full-body stereoradiographs using validated software to compare preoperative and 6 months postoperative changes with previously published adolescent norms. A sub-group analysis of patients with type 1 Lenke curves was performed comparing preoperative to postoperative alignment and also comparing this with previously published normative values.</p></sec><sec><title>Results</title><p>The mean coronal curve of the 38 AIS patients (mean age, 16±2.2 years; 76.3% female) was corrected from 53.6° to 9.6° (80.9%, <italic>p</italic>&lt;0.01). None of the thoracic and spino-pelvic sagittal parameters changed significantly after surgery in previously hypo- and normo-kyphotic patients. In hyper-kyphotic patients, thoracic kyphosis decreased (<italic>p</italic>=0.003) with a reciprocal decrease in lumbar lordosis (<italic>p</italic>=0.01), thus lowering pelvic incidence-lumbar lordosis mismatch mismatch (<italic>p</italic>=0.009). Structural thoracic scoliosis patients had slightly more thoracic kyphosis than age-matched patients at baseline and surgical correction of the coronal plane of their scoliosis preserved normal sagittal alignment postoperatively. A sub-analysis of Lenke curve type 1 patients (n=24) demonstrated no statistically significant changes in the sagittal alignment postoperatively despite adequate coronal correction.</p></sec><sec><title>Conclusions</title><p>Surgical correction of the coronal plane in AIS patients preserves sagittal and spino-pelvic alignment as compared to age-matched asymptomatic adolescents.</p></sec>

scholarly journals Revision Strategies for Harrington Rod Instrumentation: Radiographic Outcomes and Complications

2020 ◽  
pp. 219256822096075
Author(s):  
Philip K. Louie ◽  
Sravisht Iyer ◽  
Krishn Khanna ◽  
Garrett K. Harada ◽  
Alina Khalid ◽  
...  
Keyword(s):  
Adolescent Idiopathic Scoliosis ◽  
Idiopathic Scoliosis ◽  
Revision Surgery ◽  
Lumbar Lordosis ◽  
Pelvic Incidence ◽  
Vertical Axis ◽  
Sagittal Vertical Axis ◽  
Radiographic Outcomes ◽  
Harrington Rod

Study Design: Retrospective case series. Objective: The purpose of this study is to evaluate the clinical and radiographic outcomes following revision surgery following Harrington rod instrumentation. Methods: Patients who underwent revision surgery with a minimum of 1-year follow-up for flatback syndrome following Harrington rod instrumentation for adolescent idiopathic scoliosis were identified from a multicenter dataset. Baseline demographics and intraoperative information were obtained. Preoperative, initial postoperative, and most recent spinopelvic parameters were compared. Postoperative complications and reoperations were subsequently evaluated. Results: A total of 41 patients met the inclusion criteria with an average follow-up of 27.7 months. Overall, 14 patients (34.1%) underwent a combined anterior-posterior fusion, and 27 (65.9%) underwent an osteotomy for correction. Preoperatively, the most common lower instrumented vertebra (LIV) was at L3 and L4 (61%), whereas 85% had a LIV to the pelvis after revision. The mean preoperative pelvic incidence–lumbar lordosis mismatch and C7 sagittal vertical axis were 23.7° and 89.6 mm. This was corrected to 8.1° and 28.9 mm and maintained to 9.04° and 34.4 mm at latest follow-up. Complications included deep wound infection (12.2%), durotomy (14.6%), implant related failures (14.6%), and temporary neurologic deficits (22.0%). Eight patients underwent further revision surgery at an average of 7.4 months after initial revision. Conclusions: There are multiple surgical techniques to address symptomatic flatback syndrome in patients with previous Harrington rod instrumentation for adolescent idiopathic scoliosis. At an average of 27.7 months follow-up, pelvic incidence–lumbar lordosis mismatch and C7 sagittal vertical axis can be successfully corrected and maintained. However, complication and reoperation rates remain high.

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