Quality of Life Improvement Following Surgery in Adolescent Spinal Deformity Patients: A Comparison Between Scheuermann Kyphosis and Adolescent Idiopathic Scoliosis

Operative choices matter: the role of UIV and sagittal balance in the development of proximal junctional kyphosis following posterior instrumentation for Scheuermann's kyphosis

PURPOSE

This study sought to investigate associations between upper instrumented vertebra (UIV) location and the risk of proximal junctional kyphosis (PJK) at 2 years following posterior spinal fusion (PSF) for Scheuermann's kyphosis (SK).

METHODS

In this retrospective cohort study, SK patients who underwent PSF and reached 2 years postop were identified in a multicenter international registry, excluding those with anterior release, prior spine surgery, neuromuscular comorbidity, post-traumatic kyphosis, or kyphosis apex below T11-T12. Location of UIV as well as the number of levels between UIV and preoperative kyphosis apex was determined. Additionally, the degree of kyphosis correction was evaluated. PJK was defined as a proximal junctional angle ≥ 10° that is ≥ 10° greater than the preoperative measurement.

RESULTS

90 patients (16.5 ± 1.9 yo, 65.6% male) were included. Preoperative and 2-year postoperative major kyphosis was 74.6 ± 11.6° and 45.9 ± 10.5°, respectively. Twenty-two (24.4%) patients developed PJK at 2 years. Patients with UIV below T2 had a 2.09 times increased risk of PJK when compared to those with UIV at or above T2, adjusting for distance between UIV and preoperative kyphosis apex [95% Confidence Interval (CI) 0.94; 4.63, p = 0.070]. Patients with UIV ≤ 4.5 vertebrae from the apex had a 1.57 times increased risk of PJK, adjusting for UIV relative to T2 [95% CI 0.64; 3.87, p = 0.326].

CONCLUSION

SK patients with UIV below T2 had an increased risk of developing PJK at 2 years following PSF. This association supports consideration of UIV location during preoperative planning.

LEVEL OF EVIDENCE

Prognostic Level II.

Back pain in adolescent idiopathic scoliosis: A comprehensive review

Purpose

Adolescent idiopathic scoliosis (AIS) is a common spinal deformity that affects millions of children worldwide. A variety of treatment algorithms exist for patients based on radiographic parameters such as the Cobb angle and the Risser stage. However, there has been a growing focus on nonradiographic outcomes such as back pain, which can cause functional disability and reduced quality of life for patients. In spite of this, back pain in AIS is poorly characterized in the literature. We aimed to summarize various factors that may influence back pain in AIS and the impact of different treatment methods on pain reduction.

Methods

A comprehensive systematic review was undertaken using the PubMed and Cochrane database. Keywords that were utilized and combined with "Adolescent Idiopathic Scoliosis" included, "back pain," "treatment," "biomechanics," "biochemistry," "epidemiology," and "biopsychosocial." The literature was subsequently evaluated and deemed relevant or not relevant for inclusion.

Results

A total of 93 articles were ultimately included in this review. A variety of contradictory literature was present for all sections related to epidemiology, underlying biomechanics and biochemistry, biopsychosocial factors, and treatment methodologies.

Conclusion

Back pain in AIS is common but remains difficult to predict and treat. The literature pertaining to causative factors and treatment options is heterogeneous and inconclusive. Longer-term prospective studies combining biopsychosocial intervention in conjunction with existing curve correction techniques would be meaningful.

Surgical treatment of young adults with idiopathic scoliosis

OBJECTIVE

In this study, the authors report on their experience with the surgical treatment of young adults with idiopathic scoliosis (YAdISs) who did not have surgical treatment in adolescence but did require intervention after skeletal maturity.

METHODS

The medical records of YAdISs between 18 and 40 years of age who had been surgically treated at two institutions between 2009 and 2018 were retrospectively evaluated. Pre- and postoperative clinical and radiographic information was gathered and compared at 2 years after treatment.

RESULTS

Twenty-eight patients (9 male, 19 female) with a median age of 25 years (range 18-40 years) met the study inclusion criteria. Five patients (18%) had postoperative complications, including 2 deep venous thromboses, 1 ileus, and 2 reoperations, one for implant failure and the other for pseudarthrosis. The mean maximum coronal curve angle improved from 43° ± 12° to 17° ± 8° (p < 0.001), but there were no significant differences in sagittal vertical axis, lumbar lordosis, pelvic tilt, or thoracic kyphosis (p > 0.05). There was no relationship between the amount of correction obtained and patient age (p = 0.46). Significant improvements in the Oswestry Disability Index (31 vs 24, p = 0.02), visual analog scale score for both back pain (6.0 vs 4.0, p = 0.01) and leg pain (2.6 vs 1.1, p = 0.02), and self-image score (Δ1.1, p < 0.001) were seen.

CONCLUSIONS

YAdISs can present with pain, deformity progression, and/or appearance dissatisfaction because of their scoliosis despite successful nonoperative management during adolescence. Once the scoliosis becomes symptomatic, surgical correction can result in significant clinical and radiographic improvements at the 2-year follow-up with a relatively low complication rate compared to that for other types of adult spinal deformity.

Long-term results of surgical correction of Scheuermann’s kyphosis

Objective. To analyze long-term results of surgical correction of kyphosis due to Scheuermann’s disease.

Material and Methods. Design: retrospective cohort study. The study group included 43 patients (m/f ratio, 34/9). The mean age was 19.1 (14–32) years; the mean postoperative follow-up was 6 ± 10 (5–20) years. Two-stage surgery including discectomy and interbody fusion followed by posterior correction and fusion was conducted in 35 cases (Group A). Eight patients (Group B) underwent only posterior correction and spinal fusion. The following parameters were determined for each patient: thoracic kyphosis (TK), lumbar lordosis (LL) (scoliotic deformity of the thoracic/thoracolumbar spine, if the curve magnitude was > 5°), sagittal vertical axis (SVA), sagittal stable vertebra (SSV), first lordotic vertebra (FLV), proximal junctional angle (PJA) and distal junctional angle (DJA). All measurements were performed immediately before surgery, one week after surgery, and at the end of the follow-up period. All patients answered the SRS-24 questionnaire after surgery and at end of the follow-up period.

Results. Groups were comparable in terms of age and gender of patients, body mass index and initial Cobb angle (p < 0.05). The curve decreased from 77.8° to 40.7° in Group A and from 81.7° to 41.6° in Group B. The loss of correction was 9.1° and 6.0° in groups A and B, respectively. The parameters of lumbar lordosis remained normal during the follow-up period. At implant density less than 1.2, deformity correction and correction loss were 44.5° (54.7 %) and 3.9°, respectively (p < 0.05). Proximal junctional kyphosis (PJK) was detected in 21 out of 43 patients (48.8 %). The frequency of PJK was 45.4 % among patients whose upper end vertebra was included in the fusion and 60 % among those whose upper end vertebra was not included. PJK developed in eight (47.8 %) out of 17 patients with kyphosis correction ≥ 50 % and in 13 (50.0 %) of those with correction < 50 %. The rate of DJK development was 39.5 %. The lower instrumented vertebra (LIV) was located proximal to the sagittal stable vertebra in 16 cases, with 12 (75 %) of them being diagnosed with DJK. In 27 patients, LIV was located either at the SSV level or distal to it, the number of DJK cases was 5 (18.5 %); p < 0.05. Only two patients with complications required unplanned interventions. According to the patient questionnaires, the surgical outcome score increases between the immediate and long-term postoperative periods for all domains and from 88.4 to 91.4 in total. The same applies to answer to the question about consent to surgical treatment on the same conditions: positive answers increased from 82 to 86 %.

Conclusions. Two-stage surgery, as a more difficult and prolonged one, has no advantages over one-stage operation in terms of correction magnitude and stability of the achieved effect. Surgical treatment improves the quality of life of patients with Scheuermann’s disease, and the improvement continues in the long-term postoperative period.

Comparison of Changes in SRS-22 Values with Improvement in Cobb Angles after Posterior Fusion Surgery in Adolescent Idiopathic Scoliosis

INTRODUCTION

The purpose of this study was to evaluate the relationship between the correction rate in Cobb angle and the improvement in quality of life profile in terms of Scoliosis Research Society (SRS)-22 values.

PATIENTS AND METHODS

Between January 2007 and December 2013, posterior instrumentation and fusion was performed to 30 patients with adolescent idiopathic scoliosis (AIS). Patients were grouped according to their improvement rate in Cobb angles after surgery. Patients with an improvement rate of > 80% were grouped as Group A; those with an improvement rate of > 60% and ≤ 80% as Group B and those with an improvement rate of ≤ 60% were grouped as Group C. The SRS-22 questionnaire of these three groups was calculated and their relationship with the improvement in Cobb angle was evaluated.

RESULTS

No statistical difference was found among the three groups in terms of pain, appearance, function, spirit, satisfaction, and SRS-22 values (all p > 0.05).

CONCLUSION

The results of this study demonstrate that the degree of correction rate does not correlate with the degree of improvement in the SRS-22 questionnaire in patients with AIS that underwent posterior fusion and instrumentation.

Health-related quality of life outcomes in adolescent Scheuermann's kyphosis patients treated with posterior spinal fusion: A comparison with age- and sex-matched controls

PURPOSE

To assess the health-related quality of life and radiographic outcomes of surgically treated adolescent Scheuermann's kyphosis patients after minimum of 2-year follow-up and to compare the health-related quality of life with age- and sex-matched healthy controls.

METHODS

Twenty-two consecutive adolescents (mean age = 16.7 years) undergoing posterior spinal fusion for Scheuermann's kyphosis were included and matched by age and sex with two healthy controls. The health-related quality of life was evaluated using the Scoliosis Research Society-24 questionnaire. Radiographic parameters were measured for comparison preoperatively and at 6 months and 2-year follow-ups. The health-related quality of life parameters were compared with healthy controls at 2 years of follow-up.

RESULTS

The mean maximal thoracic kyphosis improved from 79° (range = 75°-90°) to 55° (range = 45°-75°) (p < 0.001), and the mean lumbar lordosis was reduced from 71° (range = 51°-107°) to 52° (range = 34°-68°) (p < 0.001) after 2 years postoperatively. Incidence of proximal junctional kyphosis (PJK) was 18%. The scores of the Scoliosis Research Society-24 improved, with statistical significance observed in pain and self-image domains from preoperative to 2-year follow-up (p = 0.002 in both domains). The self-image and function were significantly lower in the operated patients at their 2-year follow-up visit compared to controls (p = 0.023 for self-image and p < 0.001 for function).

CONCLUSION

Instrumented posterior spinal fusion improves the health-related quality of life of Scheuermann's kyphosis patients during the 2-year follow-up. The greatest improvement is observed in pain and self-image domains. The health-related quality of life in pain and activity domains reaches the level of healthy individuals, while function and self-image remain at a statistically lower level.

Selection of the optimal distal fusion level for Scheuermann kyphosis with different curve patterns: when can we stop above the sagittal stable vertebra?

PURPOSE

To investigate the optimal lowest instrumented vertebra (LIV) in the treatment of Scheuermann kyphosis (SK) with different curve patterns.

METHODS

Fifty-two SK patients who underwent posterior surgery between January 2010 and December 2017 with a minimum follow-up of 2 years were retrospectively reviewed. Patients were divided into two groups based on the curve pattern: the Scheuermann thoracic kyphosis (STK group) or Scheuermann thoracolumbar kyphosis (STLK group). Based on the relationship between the sagittal stable vertebra (SSV) and LIV, both groups were further divided into the SSV group and SSV-1 group. Radiographic parameters, distal junctional kyphosis (DJK) incidence and SRS-22 questionnaire scores were evaluated.

RESULTS

In STK and STLK groups, there were no significant differences in most pre- and postoperative radiographic assessments between SSV and SSV-1 subgroups. DJK incidence showed no significant differences between groups during follow-up (P > 0.05). LIV-PSVL was significantly more negative in the SSV-1 group than that in the SSV group (P < 0.001). Within the SSV-1 group, patients with DJK showed a more negative LIV-PSVL (P = 0.039). Moderate correlation was observed between preoperative LIV-PSVL and DJK with a Spearman coefficient of - 0.474 (P = 0.035). Receiver operative characteristic curve analysis showed that the threshold value of preoperative LIV-PSVL to predict DJK was - 37.35 mm (area under the curve 0.882).

CONCLUSION

Shorter fusion stopping at SSV-1 achieved comparable clinical outcomes and did not increase the risk of DJK for both STK and STLK patients. For patients whose preoperative LIV-PSVL <  - 37.35 mm, extending fusion to SSV is an acceptable solution to prevent DJK.

Assessment of Quality of Life for Scheuermann’s Kyphosis Patients with Cobb’s Angle 50°–65° Treated Conservatively or Surgically in North Jordan: A Prospective Comparative Study

Background

Scheuermann’s disease is the most common cause of hyperkyphosis of the thoracic spine during the adolescence period. It causes neck and lower back pain, restriction of lung expansion, traction of the spinal cord, increased vulnerability to vertebral fracture, and a hump. Patients with curves < 60° are treated conservatively, while surgery is used for patients with curves > 60°. The purpose of this prospective cohort study was to assess the quality of life and functional changes in conservatively or surgically treated Scheuermann’s disease patients with a curve size of 50°–65° in north Jordan.

Methods

Sixty-three adolescent patients with Scheuermann’s kyphosis (aged between 10 and 18 years) were treated at our hospital between January 2014 and August 2018. All patients were investigated clinically, radiologically (Cobb’s angle), and functionally (Oswestry Disability Index [ODI], Scoliosis Research Society 22 revision [SRS-22r] questionnaire, and pulmonary function test [PFT]) pre- and post-treatment (final follow-up). Patients were randomly selected for treatment method (conservative versus surgical).

Results

There were 31 patients (mean age, 15.48 ± 2.50 years) and 32 patients (mean age, 16.19 ± 1.51 years) treated conservatively and surgically, respectively. Mean ± standard deviation of ODI, SRS-22r, and Cobb’s angle of the surgical group improved from 16.8% ± 14.3%, 3.5 ± 0.5, and 58.75° ± 3.59°, respectively, pre-surgery to 13.4% ± 10.8%, 4.2 ± 0.5, and 41.53° ± 3.94°, respectively, post-surgery, while those of the conservative group became worse from 12.6% ± 13.4%, 3.9 ± 0.7, and 56.1° ± 3.3°, respectively, to 20.1% ± 13.6%, 3.5 ± 0.7, and 58.8° ± 5.8°, respectively. The surgical group showed better improvement in all scores than the conservative group (p < 0.05), as well as in PFT.

Conclusions

Surgical treatment of Scheuermann’s kyphosis with curves of 50°–65° resulted in better QOL, Cobb’s angle, and PFT than conservative treatment. This was because of lower patient cooperation in the conservative management group, which made the curve less flexible for exercises and bracing.

The body image disturbance questionnaire-scoliosis better correlates to quality of life measurements than the spinal assessment questionnaire in pediatric idiopathic scoliosis

PURPOSE

Idiopathic scoliosis (IS) patients can have body dissatisfaction which can affect their perception of health. Two body image measures, the Spinal Appearance Questionnaire (SAQ) and the Body Image Disturbance Questionnaire-Scoliosis (BIDQ-S), have been used in pediatric IS with variable correlation to the SRS-22r and radiographs, but have not been compared to each other. As patient reported outcomes (PROs) continue to be highlighted in large database studies and national hospital ranking system scoring, we should narrow use to the best and most efficient. We aim to determine which of two better correlates to pediatric IS patients' radiographs and quality of life (QoL) scores.

METHODS

Consecutive IS patients aged 10-19 years old without surgery prospectively completed BIDQ-S, SAQ, SRS-22r, and PedsQL self-reported outcome measures. BIDQ-S and SAQ were compared in correlation to the two QoL surveys, as well as to radiographic major curve, shoulder asymmetry, lateral upright ribcage offset at apex, and coronal/sagittal balance. Spearman's r was used for correlations.

RESULTS

104 surveys with mean age 14.4 years and mean major curve 42° (14°-74°) were included. BIDQ-S and SAQ scores strongly correlated to each other (r = 0.76), but BIDQ-S had a stronger correlation to total SRS-22r (- 0.75 vs - 0.61 SAQ), PedsQL total (- 0.76 vs - 0.55) and better or no difference in each SRS-22r and PedsQL domain. Both poorly correlated to radiographs (main curve: r = 0.32 BIDQ-S, 0.31 SAQ).

CONCLUSION

The BIDQ-S correlates better to SRS-22r and PedsQL for pediatric IS patients than the SAQ. Neither correlate well to radiographs.

LEVEL OF EVIDENCE

III.

Reliability and validity of a kyphosis-specific spinal appearance questionnaire

PURPOSE

Hyperkyphosis, including Scheuermann and postural kyphosis, is associated with decreased perceived cosmesis and well being. No patient reported outcome questionnaire specific to kyphosis exists. We sought to assess the internal consistency, test-retest reliability and concurrent validity of a new Kyphosis-specific Spinal Appearance Questionnaire (K-SAQ).

METHODS

A K-SAQ was developed from a modified SAQ to measure kyphosis-specific aspects of appearance. Patients with hyperkyphosis (ages 10-20 years) curves ≥ 50° completed the K-SAQ and SRS-22R at baseline and the K-SAQ 2 weeks later.

RESULTS

55 patients completed the K-SAQ and SRS-22R. 28 patients completed the K-SAQ 2 weeks later. The K-SAQ total averages showed excellent internal consistency (Cronbach's α = 0.91) and test-retest reliability (ICC = 0.84). Moderate associations were seen between the SRS-22R subtotal average score and K-SAQ total average score and (r = - 0.62, p < 0.001) and the SRS-22R self-image domain with the K-SAQ total average score (r = - 0.57, p < 0.001). Higher BMI and increased age scored worse on the K-SAQ total average, whereas only higher BMI scored worse on the SRS-22R subtotal average.

CONCLUSION

The K-SAQ is a reliable patient reported outcome measure of kyphosis-specific aspects of appearance.

The variability in location of the most prominent points on the posterior torso of those without abnormal surface topography, those with Adolescent Idiopathic Scoliosis and those with Scheuermann's Kyphosis: a seven year longitudinal analysis

The correction of adolescent scoliosis involves the recreation of torso symmetry. A symmetrical torso has equivalent areas of shape on either side of the midline. The posterior torso has two areas of prominence, known as the 'most prominent points' on either side of the midline which can be used as reference points to measure symmetry of the posterior torso. This study used the three-dimensional (3D) coordinates of the most prominent points, measured using ISIS2 surface topography and standardised by torso size, in children without abnormal surface topography, with adolescent idiopathic scoliosis (AIS) (right thoracic curves) and with Scheuermann's kyphosis (SK). The purpose was to demonstrate the variability of the position of the points in these three groups. The variability of the 3D coordinates was calculated for each group (mean, standard deviation and range in millimetres) and the standardised data were illustrated using 3D 95% confidence interval ellipsoids. In those without deformity, the position of the left and right point was mirrored with little difference. The AIS group showed a difference between the left and right points, with the right becoming further from the midline and more prominent than the left but with the left becoming more superior than the right. For the SK cohort, both left and right points moved inwards towards the midline and became more prominent. Linear mixed effect modelling was used to examine the contribution of age, kyphosis and scoliosis to the position of the most prominent points. In the cohort without abnormal surface topography, the x parameter increases with the covariates of age and kyphosis, with the covariate of age likely reflecting torso growth. The left side becomes more prominent and inferior compared to the right. In the AIS cohort, age follows the cohort without abnormal surface topography. This is added to by the scoliosis which is observed to make the right side more lateral, less inferior and more prominent, whereas the left becomes more medial, less inferior and less prominent. Kyphosis in the AIS cohort leads to the right point becoming more lateral, less inferior and less prominent whereas in the left becomes more lateral, more inferior and more prominent. In the SK cohort, the effects of the covariates of age and kyphosis are not clear reflecting the small number of cases with more than one surface topography image over time.

Validity of a one-item drawing-based instrument to assess trunk deformity perception in kyphotic deformities

INTRODUCTION

Body image and trunk appearance perception are two crucial attributes in determining the quality of life of individuals with spinal deformities. The Trunk Appearance Perception Scale (TAPS) is a drawing-based instrument used to evaluate this feature. The TAPS does not include a sagittal view of the trunk so it is never been used to assess trunk deformity perception in hyperkyphotic patients. This study aims to analyze the effect of introducing a new drawing on the TAPS scale representing the trunk view in the sagittal plane.

PATIENTS

170 non-surgical patients were included (mean age 16.9 years and 77.4% women) distributed in three groups. CONTROL group (no deformity): 22 cases; KYPHOSIS group (sagittal deformity): 49 cases and SCOLIOSIS group (coronal deformity): 99 cases (mean Cobb 42.4º).

METHOD

Cross-sectional study. A new drawing (TAPS4) was designed to represent the deformity in the sagittal plane with five response options. Clinical (SRS-22 and TAPS 4-items) and radiological (kyphosis T4-T12) data were collected in all patients. The statistical analysis consisted in determining for each group the internal consistency of the 3-items TAPS vs 4-items TAPS, as well as the discriminant validity (correlation with kyphosis magnitude) and convergent validity (correlation with the SRS-22 image subscale). In addition, test-retest reliability of new item 4 was determined in a subgroup of 30 kyphotic patients. During control visit, the patients received a complete physical examination and a full-spine AP and lateral X-ray in standing position using a low-radiation technique and fulfilled instruments TAPS 4 items and SRS-22r.

RESULTS

The three groups were found to have statistically significant differences in the magnitude of kyphosis, quality of life, body image perception, the 3-items TAPS, 4-items TAPS and new item 4 score. The addition of the item 4 to TAPS 3 items did not cause a significant change in the internal consistency of the scales (Cronbach's alpha) (TAPS 3-items 0.8 vs. TAPS 4-items 0.8). Kyphosis magnitude was not correlated with the 3-items TAPS and 4-items TAPS scores; however, in the KYPHOSIS group, a significant negative correlation was observed between kyphosis and item 4 (Rho = - 0.4, p = 0.0001). A significant correlation was found in all groups between TAPS 3-items and TAPS 4-items and SRS-22 image domain; the correlation between item 4 and SRS-22 body image domain was 0.3 in the Scoliosis group and 0.7 in the Kyphosis group.

CONCLUSIONS

The 4-items TAPS scale does not provide advantages in the assessment of trunk deformity over the 3-items scale. However, in patients with kyphosis, the item 4 (Kypho-TAPS) alone is a valid and reliable instrument to monitor the perception of the trunk deformity.

Prospective Comparison of Patient-selected Operative Versus Nonoperative Treatment of Scheuermann Kyphosis

BACKGROUND

Scheuermann kyphosis (SK) can be managed operatively or nonoperatively. Few studies compare the effect of operative versus nonoperative treatment on patient health-related quality of life. We compare 2-year radiographic and the Scoliosis Research Society-22 questionnaire (SRS-22) results of patients who self-selected either conservative or surgical treatment.

METHODS

Single institution review of prospectively collected data for patients presenting with SK from 2006 to 2014. Forty-five of 55 patients returned for 2-year follow-up. Patients were divided into operative (n=27) or nonoperative (n=18) groups based upon their self-selected method of treatment. Radiographic data and SRS-22 scores were collected at initial presentation and 2-year follow-up.

RESULTS

Operatively treated patients had larger initial sagittal Cobb angles and lower SRS-22 scores in the pain and appearance domains. Two years postoperatively, surgically treated patients had smaller Cobb angles and improved scores in these SRS-22 domains. Nonoperatively treated patients did not deteriorate over time.

CONCLUSIONS

Patients who elect to receive operative treatment for SK have improved radiographic and SRS-22 parameters at 2-year follow-up compared with patients who elect nonoperative treatment. Not surprisingly, patients selecting surgical treatment had greater sagittal Cobb angles and greater levels of pain and dissatisfaction with their appearance. However, at 2-year follow-up, surgical patients experience greater (and significant) change on all parameters; exhibiting smaller Cobb angles, less pain, and greater satisfaction with their outcomes. Nonoperatively treated patients do not deteriorate over 2 years.

LEVEL OF EVIDENCE

Level II-prognostic study.

Curve patterns deserve attention when determining the optimal distal fusion level in correction surgery for Scheuermann kyphosis

BACKGROUND CONTEXT

The surgical strategy to decide distal fusion level for Scheuermann kyphosis (SK) is controversial. Some spinal surgeons advocate that instrumentation should end at the first lordotic vertebra (FLV), whereas others recommend extending spinal fusion to the sagittal stable vertebra (SSV). Scheuermann kyphosis has two curve patterns: Scheuermann thoracic kyphosis (STK), with the curve apex above or at T10; and Scheuermann thoracolumbar kyphosis (STLK), with the curve apex below T10. To our knowledge, curve patterns have not been taken into consideration when determining the distal fusion level.

PURPOSE

This study aims to analyze the clinical and radiographic outcomes, including the distal junctional problems, in pediatric patients with STK and STLK who underwent fusion with different distal fusion levels.

STUDY DESIGN

This is a retrospective, single-center, institutional review board-approved study.

PATIENT SAMPLE

A total of 45 consecutive pediatric patients with STK or STLK.

OUTCOME MEASURES

The following parameters were evaluated: global kyphosis (GK), deformity angular ratio (DAR), correction rate of GK and DAR, thoracolumbar kyphosis (TLK), lumbar lordosis (LL), sagittal vertical axis (SVA), T1 pelvic angle (TPA), the distance from the center of the lower instrumented vertebra (LIV) to the posterior sacral vertical line, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and distal junctional kyphosis (DJK).

METHODS

This work was supported by the National Natural Science Foundation of China (Grant No. 81171672), Nanjing Clinical Medical Center, and Jiangsu Provincial Key Medical Center. Patients with STK were fused to SSV at the distal level (Group STK), whereas patients with STLK were fused to FLV (Group STLK). Whole spine x-rays obtained before surgery, immediately after operation, and at the latest follow-up were evaluated. The radiographic and clinical data were compared between Groups STK and STLK. All patients had a minimum of 2 years of follow-up.

RESULTS

Before surgery, Groups STK and STLK were comparable in terms of age, gender, body mass index, fusion levels, follow-up time, some radiographic parameters and the 22-item Scoliosis Research Society questionnaire (SRS-22) evaluation. DAR and TLK were significantly smaller, whereas PI was significantly greater, in Group STK than those in Group STLK. Despite different distal fusion strategies, STK and STLK were corrected to an equivalent extent, with similar GK, correction rate, LL, SVA, TPA, PT, and SS immediately after operation and at the final follow-up. The DAR and TLK retained were smaller, whereas the PI retained was greater, in Group STK than STLK after surgery. Distal junctional kyphosis complications were found in five patients with STK curve type. In Group STK, patients with DJK were found to have significantly larger preoperative GK (87.5±7.0 vs. 77.5±9.0, p=.024), correction rate of GK (62.9±10.2% vs. 51.3±8.5%, p=.021), and correction rate of DAR (55.9±4.5% vs. 36.6±13.7%, p=.011) than those without DJK. Pre- and postoperative SRS-22 assessments did not show any significant difference between Groups STK and STLK or between patients with and without DJK.

CONCLUSIONS

Curve patterns should be taken into attention when determining the optimal distal fusion level in correction surgery for SK. For patients with STLK, relatively shorter fusion stopping at FLV is enough to correct SK with the preservation of more lumbar motility and less development of DJK. For patients with STK, we suggest extending fusion to the SSV, which could restrict more distal junctional problems than fusion to the FLV. Large GK and correction degree might be the associated factors of developing DJK in STK patients.