Purpose
Although the Roussouly classification of common variants in spinal sagittal alignment is well accepted, no studies have implemented it in an asymptomatic adult population. In addition, no ...study investigated the radiographic features of asymptomatic patients with an anteverted pelvis. The aim of this prospective radiographic study of 296 asymptomatic adults without spinal pathology was to investigate how the Roussouly classification could include the anteverted pelvis concept.
Methods
Pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), and the lumbar parameters lumbar lordosis (Global LL), lordosis tilt angle (LTA), total number of lordotic vertebra (LL verteb), and C7 plumbline/sacrofemoral distance ratio (C7PL ratio) were evaluated in 296 healthy volunteers (126 males, 170 females; mean age, 27 years; range 18–48 years). Comparison between the five types of the Roussouly classification used Student, ANOVA, and Tukey tests for quantitative variables and
χ
2
, Fischer, and Holm tests for qualitative variables.
Results
Mean PI and PT were, respectively, (39°, 10°) for type 1, (41°, 10°) for type 2, (53°, 13°) for type 3, and (62°, 12°) for type 4 (
p
< 0.0001 and
p
< 0.01). A sizable portion (16%) of the population (type 3 AP) showed low-grade PI (mean, 48° ± 6°) despite having SS > 35°. PT was low or negative (mean 4° ± 3°). C7PL ratio was >1 (in front of the hip axis) in 13% of all cases, and between 0 and 1 (between sacrum and hip axis) in 49%.
Conclusion
Although asymptomatic adults stood with stable global balance, the sagittal spinal alignment of healthy subjects, newly divided in 5 sagittal types, varied significantly. Type 3 AP appears as a new and unusual sagittal shape with low-grade PI, very low or negative PT, and hyperlordosis. Whereas most asymptomatic adults stood with C7PL behind the hip axis, a sizeable portion had C7 in front of the hip axis. This could be a new controversial aspect of ideal spinal balance.
Purpose
To evaluate the incidence of mechanical complications in patients with adult spine deformity (ASD) treated by restoring the normal shape according to the Roussouly classification.
Methods
...This is a retrospective multicentric study with a minimum follow-up of 2 years. Patients operated on with fusion for ASD (minimum performed fusion: L2 to sacrum) were included. Patients with a history of previous spinal fusion of more than three levels were excluded. Spinal and pelvic parameters were measured on the preoperative and the immediate postoperative follow-up. All mechanical complications were recorded.
Results
A total of 290 patients met the criteria of inclusion with a minimum follow-up of 2 years. Mechanical complications occurred in 30.4% of the cohort. The most common complication was PJK with an incidence of 18% while nonunion or instrumentation failure (rod breakage, implant failure) occurred in 12.4%. 66% of the patients were restored to the normal shape according to the Roussouly classification based on their PI and had a mechanical complication rate of 22.5%, whereas the remaining 34% of patients had a complication rate of 46.8% (
p
< 0.001). The relative risk for developing a mechanical complication if the algorithm was not met was 3 (CI 1.5–4.3;
p
< 0.001)
Conclusion
In the recent literature, there are no clear guidelines for ASD correction. Restoring the sagittal spinal contour to the normal shapes of Roussouly according to the PI could serve as a guideline for ASD treatment. Ignoring this algorithm has a threefold risk of increased mechanical complications. We recommend this algorithm for treatment of ASD.
Level of evidence
IV cross-sectional observational study.
Graphic abstract
These slides can be retrieved under Electronic Supplementary Material.
The efficacy of bracing larger curves in adolescent idiopathic scoliosis (AIS) patients is uncertain. We aimed to assess the influence of night-time bracing in AIS patients with main curves exceeding ...40° Cobb angle at brace initiation.
We reviewed AIS patients treated with nighttime braces between 2005 and 2018. Patients with curves ≥ 25° and estimated growth potential were included. Patients were monitored with radiographs from brace initiation until brace weaning at skeletal maturity. Patients were grouped based on curve magnitude at initial evaluation: a control group (25-39°) and a large-curves group (≥ 40°). Progression was defined as > 5° increase.
We included 299 patients (control group, n = 125; large-curves group, n = 174). In the control group, 65 (52%) patients progressed compared with 101 (58%) in the large-curves group (P = 0.3). The lower-end vertebra (LEV) shifted distally post-bracing in 41 (23%) patients in the largecurves group. Patients with progressive large curves were younger (age 13.2 SD 1.5 vs. 13.9 SD 1.1, P = 0.009) and more premenarchal (n = 36 42% vs. n = 6 9%, P < 0.001) compared with non-progressive large curves.
Progression risk in patients with curves exceeding 40° treated with night-time bracing is similar to smaller curves. The LEV moved distally in almost one-fourth of the larger curves, possibly affecting fusion levels in cases of surgery.
Recently carbon spinal implants have been introduced in the treatment of patients with metastatic spinal cord compression (MSCC). This is expected to decrease the deflection of radiation and improve ...diagnostic imaging and radiotherapy when compared to titanium implants. The aim of this study was to determine the safety and effectiveness of spinal carbon instrumentation (CI) in patients with MSCC in a large cohort study. A total of 163 patients received instrumentation between 1 January 2017 and 31 December 2021. A total of 80 were stabilized with CI and 83 with TI. The outcome measures were surgical revision, postsurgical survival, peri-operative bleeding, and surgery time. The peri-operative blood loss in the CI-group was significantly lower than that in the TI-group: 450mL vs. 630mL, (
= 0.02). There were no significant differences between the groups in mean survival (CI 9.9) vs. (TI 12.9) months (
= 0.39), or the number of patients needing a revision (CI 6) vs. (TI 10), (
= 0.39). The median duration of surgery was 121 min, (
= 0.99) with no significant difference between the two groups. Surgical treatment with CI for MSCC is safe and an equally sufficient treatment when compared to TI.
Abstract Background Context Most literature on complications in spine surgery has been retrospective or based on national databases with few variables. The Spine AdVerse Events Severity (SAVES) ...system has been found reliable and valid in two Canadian centers, providing precise information regarding all adverse events (AEs). Purpose This study aimed to determine the mortality and examine the incidence of morbidity in patients undergoing complex spinal surgery, including pediatric patients, and to validate the SAVES system in a European population. Study design A prospective, consecutive cohort study was conducted using the SAVES version 2010 in the period from January 1, 2013 until December 31, 2013. A retrospective analysis was performed on all patients operated from November 1, 2011 until October 31, 2012 for comparison. Patient sample Patients undergoing spinal surgery at a tertiary referral center comprised the patient sample. Outcome measures Morbidity and mortality were determined according to the newest version of the SAVES system and compared with the Canadian cohort. Other outcomes were length of stay, readmission, unplanned second surgery during index admission, as well as wound infections requiring revision. Methods All patients undergoing spinal surgery at an academic tertiary referral center in the study period were prospectively included. The newest version of SAVES system was used, and a research coordinator collected all intraoperative and perioperative data prospectively. Once a week all patients were reviewed for additional events, validation of the data, and clarification of any questions. Patients were grouped according to the type of admission (elective of emergency) and age, and subgrouped according to a major diagnostic group. The survival status was registered on January 31, 2014 to obtain 30-day survival. Results A total of 679 consecutive cases were included with 100% data completion. The in-hospital mortality was 1.3% and the 30-day mortality was 2.7%; all occurring after emergency procedures. The number of intraoperative AEs was 162 (overall incidence 20%), and the number of postoperative AEs was 1,415 (overall incidence 77%). Of the patients, 2.2% had postoperative infections requiring surgical revision. Conclusions A prospective registration improves AE recognition, and our data confirm the generalizability of the SAVES system to pediatric and non-Canadian populations.
Objective: The demand for spinal fusion is increasing, with concurrent reports of iatrogenic adult spinal deformity (flatback deformity) possibly due to inappropriate lordosis distribution. This ...distribution is assessed using the lordosis distribution index (LDI) which describes the upper and lower arc lordosis ratio. Maldistributed LDI has been associated to adjacent segment disease following interbody fusion, although correlation to later-stage deformity is yet to be assessed. We therefore aimed to investigate if hypolordotic lordosis maldistribution was associated to radiographic deformity-surrogates or revision surgery following instrumented lumbar fusion.Methods: All patients undergoing fusion surgery ( ≤ 4 vertebra) for degenerative lumbar diseases were retrospectively included at a single center. Patients were categorized according to their postoperative LDI as: “normal” (LDI 50–80), “hypolordotic” (LDI < 50), or “hyperlordotic” (LDI > 80).Results: We included 149 patients who were followed for 21 ± 14 months. Most attained a normally distributed lordosis (62%). The hypolordotic group had increased postoperative pelvic tilt (PT) (p < 0.001), pelvic incidence minus lumbar lordosis (PI–LL) mismatch (p < 0.001) and decreased global lordosis (p = 0.007) compared to the normal group. Survival analyses revealed a significant difference in revision surgery (p = 0.03), and subsequent multivariable logistic regression showed increased odds of 1-year revision in the hypolordotic group (p = 0.04). There was also a negative, linear correlation between preoperative pelvic incidence (PI) and postoperative LDI (p < 0.001).Conclusion: In patients undergoing instrumented lumbar fusion surgery, hypolordotic lordosis maldistribution (LDI < 50) was associated to increased risk of revision surgery, increased postoperative PT and PI–LL mismatch. Lordosis distribution should be considered prior to spinal fusion, especially in high PI patients.
The surgical treatment of adolescent idiopathic scoliosis (AIS) involves 3-dimensional curve correction with multisegmental pedicle screws attached to contoured bilateral rods. The substantial ...corrective forces exert a high level of stress on the rods, and the ability of the rod to withstand these forces without undergoing permanent deformation relies on its biomechanical properties. These properties, in turn, are dependent on the material, diameter, and shape of the rod. The surgical treatment of AIS is characterized by the requirement for a special biomechanical profile that may differ substantially from what is needed for adult deformity surgery. This overview summarizes the current knowledge of rod biomechanics in frequently used rod constructs, with a particular focus on translational research between biomechanical studies and clinical applicability in AIS patients.
Lordosis Distribution Index (LDI) is a new radiographic parameter associated with postoperative residual symptoms in patients undergoing Transforaminal Lumbar Interbody Fusion (TLIF). Recently, it ...has been applied on patients undergoing instrumented spine surgery, however not correlated to Patient Related Outcome Measures (PROMs). This study investigates whether the obtained the postoperative LDI after TLIF surgery correlates with the clinical outcome measured with PROMs.
This study was based on prospectively obtained data in patients undergoing TLIF throughout 2017 at a Danish university hospital. Medical records and the DaneSpine Database were accessed to obtain preoperative, operative and follow-up data. Primary outcome was Oswestry Disability Index (ODI) 12 months postoperatively. Secondary outcomes included revision rate and additional PROMs.
126 patients were included. 70 patients were classified with normolordosis (56 %), 42 hypolordosis (33 %) and 14 hyperlordosis (11 %). All groups experienced significant radiological changes undergoing surgery. Average reduction in ODI at 12 months postoperatively was −15.3 (±20.0). Minimally clinical important difference was achieved in 68 patients (54.0 %). No significant difference in PROMs between LDI-groups was observed in unadjusted or adjusted analyses. Revision surgery was performed in 8 patients with normolordosis (11.4 %), 7 hypolordosis (16.7 %) and 4 hyperlordosis (28.6 %).
We found no significant correlation between postoperative LDI subgroups of normolordotic, hypo- or hyperlordotic patients and the clinical outcome of posterolateral fusion and TLIF surgery. A trend towards lower rate of revision surgery in the normolordotic group compared to the hypo- and hyperlordotic group was observed.
Purpose:
The objective of this study was to assess the outcome of patients treated with magnetically controlled growing rods (MCGRs) using a standardized distraction procedure with intended ...distraction-to-stall and to compare the outcomes between idiopathic and nonidiopathic patients.
Methods:
This was a retrospective single-center cohort study. Conversion cases were excluded. Distractions were performed with 2- to 3-month intervals with the intention of distraction-to-stall on both rods. Distraction length was measured on X-rays every 6 months. Spinal height was assessed using T1-T12 and T1-S1 annual increase.
Results:
19 patients (eight idiopathic and 11 nonidiopathic) were included. Mean age at surgery was 9.7 ± 1.9 years, and median follow-up was 1.9 years (interquartile range (IQR): 1.3–2.2). Major curve improved from median 76° (IQR: 64–83) preoperatively to 42° (IQR: 32–51) postoperatively (p < 0.001) corresponding to a curve correction of 43% (IQR: 33–51). Correction was maintained at 1- and 2-year follow-up. Median annual T1-T12 and T1-S1 height increase were 10 mm (IQR: 6–16) and 11 mm (IQR: 7–33), respectively. A total of 159 distraction procedures were performed; 83.5% of these were distracted-to-stall, and 16.5% were stopped due to discomfort. Median rod distraction per procedure was 2.0 mm (IQR: 1.6–2.7) for the concave side and 1.7 mm (IQR: 1.4–2.5) for the convex side. Five patients had implant-related complications. Patients with nonidiopathic etiology were significantly younger and had lower flexibility compared with idiopathic patients (p ≤ 0.040). However, we found no statistically significant difference in curve correction, spinal height increase, distraction length, or complications between the two groups (p ≥ 0.109).
Conclusion:
MCGR effectively corrected the deformity and increased spinal height using a distraction procedure with intended distraction-to-stall. Five of 19 patients had implant-related complications, and we found no difference in the outcomes between idiopathic and nonidiopathic patients.
Purpose:
To compare treatment efficacy between the Boston full-time brace and the Providence part-time brace in main thoracic adolescent idiopathic scoliosis (AIS).
Methods:
Patients were treated ...with either the Boston brace (n = 37) or the Providence brace (n = 40). Inclusion criteria were Risser grade ≤2, major curve between 25° and 40° with the apex of the curve between T7 and T11 vertebrae. Two-year follow-up was available in all patients unless brace treatment had reached endpoint. The primary outcome measure was main curve progression to ≥45°.
Results:
Median age was 12.6 years and median treatment length at follow-up was 25 months (interquartile range (IQR): 18–32)) with no difference between the groups (p ≥ 0.116). Initial median main Cobb angle was 29° (IQR: 27–33) and 36° (IQR: 33–38) in the Boston and Providence groups, respectively (p < 0.001). At follow-up, 13 patients (35%) had progressed to ≥45° in the Boston group versus 16 patients (40%) in the Providence group (p = 0.838). Twenty-three patients (62%) had progressed by more than 5° in the Boston group versus 22 patients (55%) in the Providence group (p = 0.685). The secondary thoracolumbar/lumbar curve progressed by more than 5° in 14 (38%) and 18 (45%) in the Boston and Providence groups, respectively (p = 0.548).
Conclusions:
Despite a larger initial curve size in the Providence group, progression of more than 5° or to surgical indication area was similar in the Boston group. Our results indicate that nighttime bracing is a viable alternative to full-time bracing also in main thoracic AIS.
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