Increased Body Mass Index Negatively Affects Patient Satisfaction After a Posterior Fusion and Instrumentation for Adolescent Idiopathic Scoliosis

Effect of clinical and radiological parameters on the quality of life in adult patients with untreated adolescent idiopathic scoliosis: a cross-sectional study

PURPOSE

The aim of this study is to evaluate the factors that affect health-related quality of life (HRQoL) in untreated adolescent idiopathic scoliosis (AIS) patients in adulthood. We investigate the effect of clinical and radiological parameters on the SRS-22 results.

METHODS

A total of 286 untreated adolescent idiopathic scoliosis patients at adult age between April 2021 and April 2022 who were admitted to our clinic were included in the study. Rotational deformities were evaluated with a scoliometer. Cobb angles, coronal balance, clavicle angle, coronal pelvic tilt, trunk shift, and apical vertebral translation were measured in standing anteroposterior X-rays. The effect of each clinical and radiological parameter on SRS-22 results was evaluated.

RESULTS

No correlation was found between gender, age, curve type, presence of gibbosity or diagnosis time, and SRS-22 scores. A negative correlation was found between the BMI of the patients and the self-image scores (r =  - 0.246, p < 0.01) and function scores (r =  - 0.193, p < 0.05). Main thoracic (MT) gibbosity negatively correlates with self-image and total SRS-22 scores. Also, negative correlations were found between lumbar/thoracolumbar (LTL) gibbosity, function, and pain scores. MT Cobb angle magnitude was negatively correlated with self-image, mental health, and total SRS-22 scores. There were negative correlations between clavicle angle and mental health score, coronal pelvic tilt and self-image score, and apical vertebral translation and pain score.

CONCLUSION

BMI, MT gibbosity, LTL gibbosity, MT Cobb angle, clavicle angle, coronal pelvic tilt, and apical vertebral translation were negatively correlated with SRS-22 domains in untreated AIS patients in adulthood.

The kyphosis–lordosis difference parameter and its utility in understanding the pathogenesis of adolescent idiopathic scoliosis

Objective

The relationship of sagittal spinal shape in the pathogenesis of adolescent idiopathic scoliosis (AIS) is recognised. What is not clear is the relationship between the sagittal shape of those without scoliosis and the potential development of AIS, including the greater prevalence in females. The use of a new parameter, the kyphosis–lordosis (KL) difference, was developed to explore this further.

Results

The KL difference was calculated for 117 males and 79 females over seven years with 831 measures made. For females, the KL difference, between the ages of 9 and 12 ½ years, decreases from 5° to nearly 0° until starting to climb again from the age of 14 years, back to 5° by the age of 16 ½ years. For males, there is a gradual decline from 9° at age 9 years to 5° at age 17 years. Both age and sex were statistically significant in the development of the parameter. When comparing to previously published data around the true, de-rotated, sagittal shape of the scoliotic spine, the KL difference has utility in explaining the female predominance in the prevalence of AIS. This adds to the weight of evidence behind understanding why AIS develops.

Do Overweight Adolescent Idiopathic Scoliosis (AIS) Patients Have an Increased Perioperative Risk for Posterior Spinal Fusion (PSF) Surgery?: A Propensity Score Matching Analysis of 374 AIS Patients

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study was to compare the perioperative outcome of posterior spinal fusion (PSF) between overweight (OW) adolescent idiopathic scoliosis (AIS) patients and the healthy-weight (HW) patients using propensity score matching analysis.

SUMMARY OF BACKGROUND DATA

Obesity was found to increase postoperative surgical complications compared with the nonobese group. In scoliosis correction surgery, association of OW and perioperative risks had been explored, but most studies were retrospective in nature.

METHODS

From 374 patients, two comparable groups were matched using propensity score matching analysis with one-to-one nearest neighbor matching and a caliper of 0.2. There were 46 HW and OW patients in each group. The main outcome measures were intraoperative blood loss, use of allogeneic blood transfusion, operative time, duration of hospital stay post-surgery, total patient-controlled analgesia (PCA) morphine usage, perioperative complications, side bending flexibility (SBF), and correction rate (%).

RESULTS

The mean age was 13.3 ± 1.7 and 13.2 ± 1.7 years for HW and OW groups, respectively. The majority of the patients were Lenke 1 curves; 32.6% (HW) and 26.1% (OW) with an average Cobb angle of 69.0 ± 19.1° and 68.8 ± 18.4° for each group, respectively. The two groups were comparable. The operation time was 145.2 ± 42.2 and 154.4 ± 48.3 minutes for HW and OW groups, respectively (P > 0.05). The intraoperative blood loss was almost similar in both groups; 955.1 ± 497.7 mL (HW group) and 1011.8 ± 552.7 mL (OW group) (P > 0.05). Total PCA morphine used was higher in OW group (30.4 ± 22.7 mg) than in the HW group (16.2 ± 11.3 mg). No complication was observed in HW group, while in OW group, one patient (2.2%) developed intraoperative seizure.

CONCLUSION

OW AIS patients (≥85th percentile) had similar mean operative time, intraoperative blood loss, allogeneic transfusion rate, length of stay, and perioperative complications compared with HW AIS patients.

LEVEL OF EVIDENCE

3.

Determinants of the biomechanical and radiological outcome of surgical correction of adolescent idiopathic scoliosis surgery: the role of rod properties and patient characteristics

PURPOSE

Aim of the study was to evaluate the role of the mechanical properties of the rod and of the characteristics of the patients (age, skeletal maturity, BMI, and Lenke type) in determining the deformity correction, its maintenance over time and the risk of mechanical failure of the instrumentation.

METHODS

From March 2011 to December 2014 120 patients affected by AIS underwent posterior instrumented fusion. Two 5.5-mm CoCr rods were implanted in all patients. For every patient, age, sex, Risser grade, Lenke type curve, flexibility of the main curve, body mass index (BMI), and percentage of correction were recorded. In all patients, the Cobb angle value and rod curvature angle (RC) were evaluated. RC changes were registered and correlated to each factor to establish a possible statistically significance in a multivariate analysis. A biomechanical model was constructed to study the influence of rod diameter and material as well as the density of the anchoring implants in determining stress and deformation of rods after contouring and implantation.

RESULTS

Radiographic and biomechanical analysis showed a different mean rod deformation for concave and convex side: 7.8° and 3.9°, respectively. RC mean value at immediate follow-up was 21.8° for the concave side and 14.6° for the convex. At 2-year minimum follow-up, RC value increases 1.5° only for the concave side. At 3.5-year mean follow-up, RC value increases 2.7°, p = 0.003, for the concave side and 1.3° for the convex, p = 0.06. The use of the stiffest material as well as of the lowest diameter resulted in higher stresses in the rods. The use of either a low or a high instrumentation density resulted only in minor differences in the loss of correction.

CONCLUSIONS

Rod diameter and material as well as patient characteristics such as BMI, age, and Risser grade play an important role in deformity correction and its maintenance over time.