Objective
To investigate stiffness-related disability (SRD) following surgical treatment in adolescent idiopathic scoliosis (AIS) patients particularly with respect to the lowest instrumented vertebra (LIV).
Summary of Background
Extensive spinal fusion inevitably results in loss of mobility which may induce SRD during activities of daily living. Few studies have examined SRD after surgical correction for AIS.
Methods
Patients who underwent surgical correction for AIS between 2014 and 2021 and were followed up for two years were included. The degree of SRD was evaluated using the Stiffness-Related Disability Index (SRDI) which consists of four categories, each containing three questions, giving a total of 12 components of the questionnaire. The SRDI scores were compared according to the (LIV) levels. Correlation analysis was performed to examine the relationship between the SRDI and legacy health-related quality of life (HRQOL) measurements.
Results
This study included 174 patients (47 males, 127 females) with a mean age of 13.8 years. Among the 12 items of the SRDI, the scores of nine items showed a significant increase after surgery. The total sum of the SRDI scores also significantly increased after surgery. Pearson correlation analysis showed that the SRDI scores were significantly correlated with ODI (Oswestry disability index), nearly all domains, and the total sum of SRS-22 (Scoliosis Research Society-22 questionnaire), and SF-36 (Short Form 36 health questionnaire). No differences in the SRDI score were found among cases with the LIV between T12 and L3. However, The SRDI scores of patients with LIV at L4 were significantly higher than those of patients with other LIV levels. .
Conclusions
Various degree of SRD occurred after spinal fusion for AIS. The SRDI significantly correlated with the HRQOL measures. The SRDI score was highest in patients with the LIV at L4 compared to those with other LIV levels.

Background
The Selective thoracic fusion (STF) may be associated with risk of postoperative coronal decompensation, lumbar decompensation and adding-on phenomenon, which can lead to persistence of the lumbar curve and consequently to deviation of the trunk. Therefore, the STF is the most debatable issue as the optimal surgical correction in adolescent idiopathic scoliosis with Lenke 1C curves.
Methods
A total of 30 patients with adolescent idiopathic scoliosis with Lenke 1C curves who underwent STF between 1996 and 2017 were included. Minimum follow-up duration was five years. We analyzed the incidence of coronal decompensation, lumbar decompensation, distal adding-on phenomenon and trunk shift in these patients for radiographic adverse event. Clinical outcome was assessed by using the Scoliosis Research Society (SRS)-22r scores.
Results
The mean age at the time of surgery was 13.8±2.9 years. The mean follow-up duration was 80.4±12.3 months. The Cobb’s angle for main thoracic curve improved by 59.6% (p<0.001), and also The Cobb’s angle for thoracolumbar/ lumbar curve improved by 40.5% comparing preoperative and postoperative values (p<0.001). There was significant improvement in the Cobb’s angle for main thoracic and Thoracolumbar/lumbar curve comparing preoperative and last follow-up values (p<0.001). At last follow-up, the coronal balance was 10.3 ± 9.1 that significant improved from the immediate postoperative value (p=0.033). The incidence of coronal decompensation, lumbar decompensation, adding-on and trunk shift in our cohort was 16.7%, 10.0%, 13.3% and 10.0% respectively. The average SRS score at last follow-up in patients with radiographic adverse events was 4.3±0.5. That of patients without adverse events was 4.4±0.6. All domains between patients with and without adverse events had no statistical significance difference.
Conclusions
Selective thoracic fusion in Lenke 1C curves have acceptable risk of coronal decompensation, lumbar decompensation, distal adding-on, trunk shift. However, no revision surgery was required in these patients after long term follow-up. Therefore, STF in Lenke 1C curves seems to be enough.

Purpose
To evaluate the impacts of regional and socioeconomic factors on adolescent idiopathic scoliosis (AIS) diagnosis and treatment using national datasets of the Korean National Health Insurance System. The prevalence of, and therapeutic trends in, AIS are affected by a variety of environmental factors.
Materials and Methods
We analyzed random samples from datasets (10% of all entries) between 2012 and 2018, including in terms of patient demographics, residential status (a “special city”, and urban, and rural regions) and socioeconomic status (SES) based on health insurance premiums (which distinguish National Health Insurance and Medical Aid [MA] beneficiaries).
Results
The AIS prevalence was approximately 1.6-fold higher in females than in males, whereas the rate of male surgery was approximately 1.5-fold higher than that in females. AIS prevalence was higher among National Health Insurance beneficiaries (in all years), whereas the surgery rate was higher among MA beneficiaries (in most years). In all years, AIS prevalence was significantly higher among special city residents than in urban and rural residents. However, the surgical treatment rates were higher in the latter regions.
Conclusions
Our nationwide evaluation revealed AIS prevalence rates and therapeutic trends. AIS epidemiology varies by region and economic status.

The minimally invasive technique to correct deformity in scoliosis is not a familiar concept among spine surgeons but is interesting, as this innovative surgery, if it proves successful, will have the advantages of the minimally invasive technique in the final outcomes and will be the future of scoliosis surgery. We operated on 18 adolescent idiopathic scoliosis (AIS) patients using a newly designed technique which utilizes two or three 1-inch midline incisions to insert pedicle screws with a rod, facet fusion and de-rotation maneuver to correct the deformity. Post-operative complications were minimal and the results of the deformity corrections were comparable to the open scoliosis surgery in the follow up. The advantages of minimally invasive surgery observed in all cases include cosmetically fainter scars, reduced blood loss, shorter hospital stay, early mobilization and minimal need of analgesics for pain. Even though many challenges were faced in executing this procedure, the goal of inventing this novel approach was accomplished. We feel this technique is a good alternative to open surgery in certain curve types of AIS but large scale studies are needed in the future to recommend its routine use.

Purpose
Preoperative and postoperative trunk asymmetry were measured by 3-D full body scanner in scoliosis patients. Measured variables between operation were compared. And also compared with radiologically measured varaibles.
Materials and Methods
From february 2011 to august 2011, 20 patients with idiopathic scoliosis were treated by surgical operation. Mean age was 17.2. Using 3-D full body scanner (Medicube®), left and right side difference of weight balance, shoulder height, shoulder volume, shoulder gradient, rib hump gradient between operation were measured. Radiologically measured apical vertebra rotation (by Nash-Moe method) and 3-D scanned rib hump gradient were compared. Also radiologically measeured shoulder height (coracoid height difference) and 3-D scanned shoulder height were compared.
Results
Mean left and right side difference between operation is ; 3.2% in weight balance, 1.1% in shoulder height, 15% in shoulder volume, 3.24° in shoulder gradient, 4.72° in rib hump gradient. Differences except shoulder height were statistically significant. Rib hump gradient has the strongest significance (p-value<0.001), and improved averagely 3.4° in 15 patients. Apical vertebra rotation and rib hump gradient showed positive relation.
Conclusion
After deformity correction operation in idiopathic scoliosis patient, most of trunk measures showed significant difference, and rib hump gradient reflected apical vertebra rotation. In conclusion, 3-D full body scanner can be useful method to evaluate trunk symmetry in idiopathic scoliosis patient.

We reviewed literatures relating to minimally invasive lateral lumbar interbody fusion for the treatment of adult degenerative spinal deformity. Most of literatures were retrospective case series with a small numbers of patients. A prospective multicenter study was published in two separate papers. This procedure was effective in treating the coronal deformity. On the other hand, restoring the sagittal plane remains an issue. Pseudarthrosis was problematic, especially in the cases without use of the human recombinant bone morphogenetic protein-2 (rhBMP-2) and bilateral pedicle screw fixation. Temporary sensory deficits and transient leg weakness was the most common complication after lateral lumbar interbody fusion. Careful patient selection is important for the application of lateral minimally invasive techniques for adult degenerative scoliosis.

Lumbar degenerative scoliosis (LDS) has been increased with increased aging population. The conventional surgical treatment method of LDS was posterior decompression followed by lumbar fusion. However, these surgeries usually require long-level fusion with increased risk of much bleeding and perioperative morbidity especially in old patients. The correction of sagittal or coronal imbalance is also important in the surgical treatment of LDS, thus osteotomy may be sometimes required. Direct lateral interbody fusion (DLIF) has been introduced as a part of minimally invasive surgery. With DLIF technique, the stenotic canal or foramen can be decompressed indirectly without laminectomy and the lumbar lordosis can be restored through the disc height distraction. Recently, DLIF has been also used for the surgical treatment of LDS. With use of DLIF for LDS, it has been reported that the lumbar lordosis and coronal curve angle were restored and the clinical outcome was also favorable without significant surgical morbidities. The lateral approach sometimes carries the risk of the lumbar plexus palsy or vessel injuries. DLIF can be a good alternative to the posterior fusion technique for the treatment of LDS in that it can minimize the perioperative morbidity and it can also restore the sagittal or coronal radiographic profiles effectively.