Pulmonary function and health-related quality of life in patients with early onset scoliosis after repeated traditional growing rod procedures

Optimal timing of starting growing rod treatment for early-onset scoliosis

BACKGROUND CONTEXT

Growing rod (GR) systems require periodical surgical intervention and may cause associated complications, as well as worsened sagittal plane deformity. Generally, the risk of complications decreases with an increment in age at the time of the index surgery with GR construct placement. However, the optimal timing to begin GR treatment has not reached a consensus yet.

PURPOSE

This study was performed to investigate the effect of age at the index GR surgery on the complication rates and formulate clinical guidelines for the optimal timing to begin GR treatment for EOS patients.

STUDY DESIGN

Kaplan-Meier analysis was used to determine complication occurrence as a function of the age at the index surgery and to determine the survival rates for the procedures. The receiver operator characteristic (ROC) curve was used to determine optimal cut-off values for the optimal timing of index surgery based on whether complications occurred or not.

PATIENT SAMPLE

54 patients who met the criteria were enrolled in this study.

OUTCOME MEASURES

The following spinal parameters were measured: major coronal Cobb angle, global kyphosis (GK), and coronal balance (CB). CB was defined as the horizontal distance from the C7 plumb line to the center sacral vertical line.

METHODS

All patients had completed GR treatment and had a minimum 1-year follow-up duration after the final surgical intervention. Patient data were collected as follows: age at the index surgery, gender, diagnosis, type of GR construct, and the number of lengthening procedures. The standing full-spine radiographs were obtained before and after the index surgery, before and after each lengthening procedure, before and after the final surgical intervention, and at the latest follow-up. Complications were categorized as implant, alignment, and general.

RESULTS

Kaplan-Meier analysis of complications demonstrated a declining trend in complication rates with increasing age at the index surgery. The absence of perioperative complications was targeted, we constructed the ROC curve and the cut-off value was 71.0 months. Age at the index surgery was therefore categorized into two groups: younger-age group (≤ 71.0 months) and advanced-age group (> 71.0 months). There was a higher complication rate for the younger-age group than versus the advanced-age group (61.5% vs 22.0%, p=.011). PJK as a major alignment-related complication, was more frequent in the younger-age group than in the advanced-age group (30.8% vs 4.9%, p=.025). But the advanced-age group exhibited significantly more severe deformities before GR surgery compared to the younger-age group.

CONCLUSIONS

This study shows that the elevated risk of complications observed in the younger-age group, which can be attributed to the younger age at the index surgery and the increased number of lengthening procedures during treatment. We suggest deferring the initiation of GR treatment until after the age of six years for EOS patients. We hope it will serve as a basis for GR technique in the treatment of EOS, with the ultimate goal of enhancing treatment outcomes for this challenging disorder.

Patient-perceived factors on treatment satisfaction in early onset scoliosis treated surgically with a minimum of ten years

BACKGROUND

The prognosis of surgically treated subjects with early onset scoliosis (EOS) into adulthood has been lacking. We aimed to investigate the patients' perspectives on satisfaction with surgical treatment.

METHODOLOGY

We included all surgical candidates with EOS who had undergone index spinal surgery for scoliosis correction between 2009 and 2013. The minimum duration of postoperative follow-up was 10 years at the time of survey completion. Three questionnaires were used in this study, comprising the revised Scoliosis Research Society questionnaire (SRS-22r), the Patient-Reported Outcomes Measurement Information System (PROMIS-29), and the World Health Organization Quality of Life (WHOQOL-BREF). Measures of treatment satisfaction were retrieved from SRS-22r.

RESULTS

There were 29 participants who completed the survey, and thereby included in the study (i.e., a response rate of 43% and a dropout rate of 6%). Amongst them, 14, 11, and 4 individuals received posterior spinal fusion (PSF), magnetically controlled growing rods (MCGR), and traditional growing rods, respectively. The average duration after the index spinal surgery was 12.6 ± 2.2 years. Our findings revealed that self-image (across all treatment groups), sleep disruption (only in PSF), and social aspects (in both PSF and MCGR) were significantly worse when compared to the normative values. According to the multivariable linear regression model (R-square = 0.690, p < .001), an increase in SRS-22r mental health (p = .008) and PROMIS-29 social participation scores (p = .004) corresponded to 0.511 and 0.055 points increases in satisfaction. Every unit increase in PROMIS-29 fatigue (p = .043) and WHOQOL-BREF physical domain scores (p = .007) was in conjunction with 0.019 and 0.040 points decreases in satisfaction. SRS-22r self-image (p = .056) and WHOQOL-BREF environmental domain scores (p = .076) were included in the model but did not reach statistical significance.

CONCLUSIONS

To improve the long term quality of life in surgical candidates with EOS, we demonstrated that mental health, social participation, fatigue, and physical health were significant factors associated with treatment satisfaction. Interestingly, demographic and radiographic parameters did not have a significant effect in our cohort.

Early Onset Scoliosis and Adolescent Idiopathic Scoliosis: A Review of the Literature and Correlations With Pulmonary Dysfunction

In the management of early onset scoliosis (EOS) and adolescent idiopathic scoliosis (AIS), orthopedic surgeons are tasked with considering the effects that curves and their treatment can have on the respiratory system, possibly the most relevant being pulmonary dysfunction due to thoracic cage changes. The pulmonary impairment that occurs as a result of scoliosis varies widely and requires a multimodal response, including physiologic testing, such as pulmonary function tests (PFTs) and consistent psychosocial monitoring of the patient. This forces healthcare providers to consider all factors affecting the patient's quality of life (QOL) and not just the primary pathology they are treating. One method that could be utilized to ensure a more holistic approach to treatment is the use of patient-reported outcome measures (PROMs) to assess the QOL domains. Thus, this review serves to highlight the importance of addressing and correcting pulmonary dysfunction in the care of children with EOS and AIS in a holistic manner.

Thoracic insufficiency syndrome: Approaches to assessment and management

Thoracic insufficiency syndrome (TIS) was described in 2003 as the inability of the thorax to support normal respiration or lung growth. TIS includes a broad and disparate group of typically degenerative thoracospinal conditions. Although TIS arises due to a heterogeneous group of disorders and thus its incidence is not well quantified, general approaches to management and treatment exist. Evolving imaging techniques and measurements of health-related quality of life augment tests of pulmonary function to quantify disease burden, longitudinally and pre- and post-intervention. Intervention is primarily via growth-sparing surgery, for which several device options exist, to preserve vertical growth prior to a definitive spinal fusion at skeletal maturity.

The application of finite element analysis to determine the optimal UIV of growing-rod treatment in early-onset scoliosis

Objectives: To analyze the stress distribution in the proximal vertebral body and soft tissue of dual growing-rod (GR) with different upper instrumented vertebra (UIV) to determine the optimal UIV.

Methods: A ten-year-old male EOS case treated with GR was selected. Based on spiral computed tomography (CT) scanning performed in 0.6 mm thick slices, a finite element model (FEM) of the preoperative state (M0, the original spine state) of the patient was created. Subsequently, four models with different UIV fixations were numerically analyzed by FEM, including M1 (UIV = T1, i.e., the upper-end vertebrae (UEV) of the upper thoracic curve), M2 (UIV = T2), M3 (UIV = T3) and M4 (UIV = T4, i.e., the lower end vertebrae (LEV) of the upper thoracic curve). Displacement and maximum stress in the proximal vertebral body and soft tissue were measured and compared among the five models.

Results: The spine model was fixed with the sacrum, and the gravity conditions were imposed on each vertebral body according to the research of Clin and Pearsall. The results are as follows:M4 model has the largest overall displacement, while M1 has the least displacement among the four models. Except M2, the maximum normalized stress of UIV increases with the downward movement of UIV. M1 has the lowerest annulus fibrosus stress and highest joint capsule stress, which is characterized by the vertebrae backward leaning, while M4 is the opposite. The supraspinous ligament stress of M3 and M4 is significantly higher than that of M1 and M2. This suggests that UIV downshift increases the tendency of the proximal vertebral bodies to bend forward, thereby increasing the tension of the posterior ligaments (PL).

Conclusion: The UIV of the GR is recommended to be close to the UEV of the upper thoracic curve, which can reduce the stress of the proximal PL, thereby reducing the occurrence of proximal junctional kyphosis (PJK).