Scoliosis Research Society Outcomes Research Articles

Does Correction of Preoperative Coronal Imbalance Make a Difference in Outcomes of Adult Patients With Deformity?

Retrospective study with prospectively collected outcomes data. Determine the significance of coronal balance on spinal deformity surgery outcomes. Sagittal balance has been confirmed as an important radiographic parameter correlating with adult deformity treatment outcomes. The significance of coronal balance on functional outcomes is less clear. Eighty-five patients with more than 4 cm of coronal imbalance who underwent reconstructive spinal surgery were evaluated to determine the significance of coronal balance on functional outcomes as measured with the Oswestry Disability Index (ODI) and Scoliosis Research Society outcomes questionnaires. Sixty-two patients had combined coronal (>4 cm) and sagittal imbalance (>5 cm), while 23 patients had coronal imbalance alone. Postoperatively, 85% of patients demonstrated improved coronal balance. The mean improvement in the coronal C7 plumb line was 26 mm for a mean correction of 42%. The mean preoperative sagittal C7 plumb line in patients with combined coronal and sagittal imbalance was 118 mm (range, 50-310 mm) and improved to a mean 49 mm. The mean preoperative and postoperative ODI scores were 42 (range, 0-90) and 27 (range, 0-78), for a mean improvement of 15 (36%) (P = 0.00001; 95% CI, 12-20). The mean Scoliosis Research Society scores improved by 17 points (29%) (P = 0.00). Younger age (P = 0.008) and improvement in sagittal balance (P = 0.014) were positive predictors for improved ODI scores. Improvement in sagittal balance (P = 0.010) was a positive predictor for improved Scoliosis Research Society scores. In patients with combined coronal and sagittal imbalance, improvement in sagittal balance was the most significant predictor for improved ODI scores (P = 0.009). In patients with preoperative coronal imbalance alone, improvement in coronal balance trended toward, but was not a significant predictor for improved ODI (P = 0.092). Sagittal balance improvement is the strongest predictor of improved outcomes in patients with combined coronal and sagittal imbalance. In patients with coronal imbalance alone, improvement in coronal balance was not a factor for predicting improved functional outcomes.

Proximal Junctional Kyphosis in Primary Adult Deformity Surgery

: Multiple studies have reported on the prevalence of proximal junctional kyphosis (PJK) following spinal deformity surgery; however, none have demonstrated its significance with respect to functional outcome scores or revision surgery. : To evaluate if 20° is a possible critical PJK angle in primary adult scoliosis surgery patients as a threshold for worse patient-reported outcomes. : Clinical and radiographic data of 90 consecutive primary surgical patients at a single institution (2002-2007) with adult idiopathic/degenerative scoliosis and 2-year minimum follow-up were analyzed. Assessment included radiographic measurements, but most notably sagittal Cobb angle of the proximal junctional angle at preoperation, between 1 and 2 months, 2 years, and ultimate follow-up. : Prevalence of PJK ≥20° at 3.5 years was 27.8% (n = 25). Those with PJK ≥20° at ultimate follow-up were older (mean 56 vs 46 years), had lower number of levels fused (median 8 vs 11), and were proximally fused to the lower thoracic spine more often than upper thoracic spine (all P < .001). PJK ≥20° was associated with significantly higher body mass index and fusion to the sacrum with iliac screws (P < .016, P < .029, respectively). Scoliosis Research Society outcome score changes were lower for PJK patients, but not significantly different from those in the non-PJK group. : PJK ≥20° in primary adult idiopathic/degenerative scoliosis does not lead to revision surgery for PJK, but is univariately associated with older age, shorter constructs starting in the lower thoracic spine, obesity, and fusion to the sacrum. The negative results, supported by Scoliosis Research Society outcome data, provide important guidance on the postoperative management of such PJK patients. : BMI, body mass indexLIV, lowest instrumented vertebraeODI, Oswestry Disability IndexPJ, proximal junctionalPJK, proximal junctional kyphosisSRS, Scoliosis Research SocietyUIV, upper instrumented vertebra.

Reply to Letter to the Editor: Combined Anterior-Posterior Surgery is the Most Important Risk Factor for Developing Proximal Junctional Kyphosis in Idiopathic Scoliosis

The posterior tension band complex, as articulated so clearly by Dr. Yoshihara, in my opinion makes an important contribution to the etiology of proximal junctional kyphosis (PJK). However, my hesitation in attributing the posterior tension band as the most important risk factor is largely owing to the lack of supportive data in the current literature. This lack of data lies partially in the difficulty of measuring the preservation of the posterior structures and lack of consistency with which the data often are presented. For example, if the dissection of the posterior muscular attachments to transverse processes of the upper thoracic vertebrae plays a pivotal role in the development of PJK, studies should consistently show upper instrumented vertebrae of T1–T6 having a higher incidence of PJK [1]. More recent literature comparing PJK rates in those with upper thoracic (T1–T3) versus lower thoracic (T10–T12) instrumented vertebrae [4, 8] have determined that upper instrumented vertebrae in the lower thoracic spine had a higher PJK rate. In addition, some studies [4–8] have failed to show a difference in PJK rates between different upper instrumented vertebrae. The etiology of PJK is clearly multifactorial and therefore, studies should focus on conducting multivariate analyses when identifying risk factors associated with the development of PJK. We did not investigate the posterior soft tissue integrity. As mentioned by Dr. Yoshihara, the difficulty in including this as a risk factor lies in the inability to reliably quantify the extent of soft tissue dissection and facet capsule disruption at the time of the index operation. One point mentioned by Dr. Yoshihara is that pedicle screw instrumentation damages the supraadjacent facet capsule owing to the footprint of the screw head. Although I agree this is theoretically possible, this has not been supported consistently in the literature [2, 4, 7, 10]. If this were true, one would expect constructs using hooks at the upper instrumented vertebrae to have lower rates of PJK. In fact, reports are inconsistent when it comes to instrumentation type at the upper instrumented vertebrae and PJK, with one report [2] showing a difference and others [4, 7, 10] showing no difference whether a pedicle screw or a hook is used at the upper instrumented vertebrae. As our understanding of the etiology of PJK improves, the spectrum of pathologic features encompassing PJK is becoming more transparent. Earlier studies have described PJK to be a pure radiographic finding [1, 6] while more recent studies [4, 5] suggest differences in Scoliosis Research Society outcomes scores between those with and without PJK. In studies such as those referenced by Dr. Yoshihara [2, 3, 9], no differences in health-related quality of life questionnaires were noted between patients with and without PJK and therefore, the amount of increase in PJK angle noted may be of questionable clinical importance (if it is attributed solely to the posterior approach). This shows the necessity in distinguishing purely radiographic PJK versus progressive PJK causing pain versus catastrophic PJK which often can present with myelopathy and spinal cord impingement. Studies that focus on differences between these subsets of patients with PJK will be useful in determining clinically important risk factors since it is entirely plausible that the inclusion of less severe cases of PJK with more severe cases in a study cohort can have an umbrella effect and dilute otherwise important findings. At the recent Hibbs Society Meeting held during the 2012 Annual Scoliosis Research Society Meeting in Chicago, Illinois, USA, a group of surgeons met with interest on the topic of PJK. It is clear that our understanding of PJK has improved since it was first described [1] but much work remains in understanding the cause and optimal method for treating severe cases. I believe these questions will be answered in future studies and will help us tailor methods for the prevention of PJK.

Adding Thoracic Fusion Levels in Lenke 5 Curves

Multicenter; review of prospectively collected data. To determine the risks and potential benefits of nonselective versus selective fusion in a matched set of patients with Lenke 5 curves. The Lenke classification suggests a limited thoracolumbar/lumbar fusion for type 5 curves, although many experienced adolescent idiopathic scoliosis surgeons, at times, include a fusion of the thoracic curve. METHODS.: Prospectively collected cases from a multicenter database were analyzed. Patients with Lenke type 5 scoliosis curves were divided into 2 groups: 109 selective or short (only thoracolumbar/lumbar curve fused), and 41 nonselective or long (both thoracolumbar/lumbar and thoracic curves fused). Patients were then matched on the basis of the preoperative radiographical and clinical measures. Two-year postoperative radiographical and clinical outcomes were compared, using analysis of variance, with Bonferroni correction (P < 0.008). Twenty-nine matched pairs (58 patients) with Lenke 5 curves were identified. There were no preoperative differences between groups in age, thoracic or lumbar Cobb angle, curve flexibility, thoracic kyphosis, clinical trunk flexibility, or Scoliosis Research Society outcomes questionnaire scores. Postoperatively, patients in the nonselective group exhibited greater coronal correction for thoracic (residual Cobb; 22° vs. 12°) and lumbar curves (residual Cobb; 19° vs. 13°). However, the longer fusions had significantly less thoracic kyphosis (27° vs. 18°), truncal side bending (14 vs. 10 cm), and rotational flexibility (53° vs. 42°). There was no difference in clinical balance or Scoliosis Research Society questionnaire, version 22, scores. Adolescent idiopathic scoliosis surgeons attempt to achieve balanced correction with the fewest motion segments fused. Our data suggest that fusion of the thoracic curve in primary thoracolumbar scoliosis may improve coronal correction, but at the cost of decreased thoracic kyphosis and clinical flexibility 2 years postoperatively.

Comparative Analysis of Hook, Hybrid, and Pedicle Screw Instrumentation in the Posterior Treatment of Adolescent Idiopathic Scoliosis

Spinal instrumentation in adolescent idiopathic scoliosis (AIS) aims to correct spinal deformity and maintain long-term spinal stability until bony healing is ensured. The purpose of this study was to compare the minimum 2-year postoperative radiographic and clinical results of posterior spine correction and fusion with all-hook instrumentation versus hybrid segmental instrumentation versus pedicle screw instrumentation for AIS from a single institution. A total of 105 patients with AIS who underwent a posterior spinal fusion with segmental pedicle screw (35), hook (35), or hybrid (35) instrumentation were sorted and matched according to the following criteria: similar age at surgery, identical Lenke curve types, curve magnitude, and Risser grade. Patients were evaluated before, immediately after, and at 2 years after surgery for radiographic parameters, complications, and outcome, as well as on the basis of the Scoliosis Research Society (SRS) questionnaire. The age and Risser grade, major curve Cobb angle, apical vertebral rotation (AVR), apical vertebral translation (AVT), lowest instrumented vertebral tilt, global coronal and sagittal balance, lumbar lordosis, and thoracic kyphosis were determined as part of preoperative evaluation. All 3 groups showed significant differences between the preoperative and postoperative major curve Cobb angle, lowest instrumented vertebral tilt, AVT, and AVR. At the latest follow-up, lumbar lordosis, thoracic kyphosis, and global coronal and sagittal balance remained similar among the 3 groups. Major curve Cobb angle, AVT, and AVR were significantly different--the hook group's measurements were significantly higher than the other groups, but there was no difference between the pedicle screw and hybrid groups. Major curve correction rate was significantly different among all groups (screw=71.9%±13.8%, hybrid=61.4%±16.6%, hook=48.1%±19.7%) (P<0.001). The pedicle screw group had the least amount of correction loss but there was no statistically significant difference between groups (screw=2.6±6.7 degrees, hybrid=4.5±7.4 degrees, hook=4.4±6.2 degrees) (P=0.35). The hook group had the least amount of AVT correction, but the screw group and the hybrid groups were similar (pedicle=67.3%±15.5%, hybrid=57.5%±22.4%, hook=39.9%±32.5%) (P<0.001). Surgery time and blood loss were higher in the screw group. No differences in global SRS-22 scores were demonstrated between the patients treated with pedicle screw, hybrid, and hook constructs; however, the satisfaction domain was higher in the screw group at the latest follow-up. Pedicle screw and hybrid instrumentations offer significantly better spinal deformity correction than hook constructs in major curve coronal correction, AVT, and AVR. Patients with pedicle screw instrumentation had the greatest curve correction percentage, maintenance of this correction in the coronal and sagittal planes, and higher patient satisfaction by the SRS outcome scores. Global SRS-22 scores were similar at 2-year follow-up in all groups. Therapeutic level III retrospective comparative study.

The Association of Patient Characteristics and Spinal Curve Parameters With Lenke Classification Types

Retrospective review. To determine the association of patient characteristics and spinal curve parameters with Lenke curve types. The Lenke curve classification may be used for surgical planning and clinical research. We retrospectively reviewed the records of 1912 patients with adolescent idiopathic scoliosis who underwent initial surgery at 21 years of age or younger; collected data on patient's age, patient's sex, primary curve magnitude (<50°, 50°-75°, and .75°), and Scoliosis Research Society (SRS) outcomes questionnaire (SRS-22) score; and compared that data by Lenke curve type. Analysis of variance and χ tests were used as appropriate (significance level, P ≤ 0.005). RESULTS.: Lenke types vary by sex: male patients had more major thoracic (types 1-4) than major thoracolumbar/lumbar (types 5 and 6) curves, fewer lumbar C-modifiers (32% vs. 44%), and less apical lumbar translation (1.1 vs. 1.7 cm). Lenke types vary by frequency: the most common type was 1 (50%); the least common, 4 (4%). Lenke types vary by magnitude: type 4 had the greatest percentage of large curves (52% of curves .75°), most smaller curves were types 1 and 5, and type 4 had the largest mean magnitude (78° ± 17°). Lenke types vary by patient age: type 5 curves occurred in the oldest patients (average age at surgery: 15.4 ± 2.2 vs. 14.3 ± 14.6 years for all others) despite having the lowest mean magnitude (P = 0.001); curve size was negatively correlated with age at surgery (r = -0.16, P = 0.001). Lenke types vary by patient self-image: patients with type 4 curves had lower preoperative SRS outcome scores for self-image than did patients with type 1 curves (P = 0.005). Lenke types vary by sex, frequency magnitude, patient age, and patient self-image, which should be considered in designing studies.

Culture and Ethnicity Influence Outcomes of the Scoliosis Research Society Instrument in Adolescent Idiopathic Scoliosis

Retrospective comparative study. To report preoperative differences in the Scoliosis Research Society Outcomes Instrument (SRS-30) between multiple US ethnicities and native Japanese and Korean children with adolescent idiopathic scoliosis (AIS). The SRS-24 was developed in a US cohort with AIS. Comparative studies using the SRS-24 between US and Japanese patients showed differences, suggesting that culture might affect functional outcome. Preoperative SRS-30 outcomes were collected from 1853 children with AIS from 6 different ethnic groups: US white (1234), black (213), Hispanic (78), and Asian (29), as well as native Japanese (192) and Koreans (107). Analysis of covariance of 4 SRS-30 domains (pain, appearance, activity, and mental) was compared between groups adjusting for differences in age, sex, major curve magnitude, and body mass index. Pairwise comparisons of the 4 SRS-30 domains were adjusted for multiple comparisons, using Bonferroni correction. A P value of less than 0.05 was considered significant. Significant differences between ethnicities were found in all domains (P < 0.001). Whites reported more pain than Japanese or Koreans (Japanese = 4.52, Korean = 4.47, white = 4.04). Korean and Japanese patients had the lowest appearance scores (Japanese = 2.89, Korean = 2.73, US Asian = 3.55, Hispanic = 3.11, black = 3.47, white = 3.29). Koreans also had the lowest activity (Korean = 3.64, Japanese = 4.24, US Asian = 4.07, Hispanic = 4.02, black = 4.06, white = 4.16), mental (Korean = 3.70, Japanese = 4.23, US Asian = 4.05, Hispanic = 3.75, black = 4.03, white = 3.94), and total scores (Korean = 3.63, Japanese = 3.92, US Asian = 4.02, Hispanic = 3.75, black = 3.92, and white = 3.84). Culture and ethnicity influence SRS-30 outcomes in AIS. Whites reported more pain than Japanese and Koreans. Japanese and Koreans had the lowest appearance scores. Koreans additionally were distinguished by the lowest activity, mental, and total scores. These cultural and ethnic differences must be taken into account when counseling patients with AIS and studying functional outcomes.

Idiopathic scoliosis and pelvic floor dysfunction

Background: Research suggests that trunk and pelvic floor muscles work as a functional unit for postural and continence activities. Back pain increases the risk of incontinence, and practitioners treating incontinence often treat trunk muscles, while those treating back and sacroiliac problems often incorporate pelvic floor treatments in management programmes. It was hypothesized that women with scoliosis might have pelvic floor dysfunction. Methods: Pelvic floor function was evaluated in a convenience sample of four nulliparous women with idiopathic scoliosis. Evaluation included scoliometer and perineometer measures, manual muscle testing of the pelvic floor, the Pelvic Floor Distress Inventory-Short Form 20 (PFDI-20), and the Scoliosis Research Society Outcomes Instrument (SRS-22) Findings: Half the participants reported clinically significant PFDI-20 score elevations. All had back pain, attributed to their scoliosis. Conclusion: Pelvic floor strength assessments lacked sensitivity in this population of young women, but PFDI-20 scores identified who might benefit from further evaluation. Practitioners treating women with scoliosis should be aware of possible co-existing pelvic floor disorders and of the known link between back pain and incontinence. By raising this issue or using a sensitive tool like the PFDI-20 it may be possible to identify and treat problems early, and implement pelvic floor disorder prevention programmes.

Quality of life for Chinese patients with adolescent idiopathic scoliosis: evaluation of the Chinese version of the Scoliosis Research Society's outcomes instrument 22

Objective To evaluate the health-related quality of life ( HRQL) of patients with adolescent idiopathic scoliosis ( AIS) before treatment. Methods Sixty-two female patients with AIS were evaluated using the Chinese version of Scoliosis Research Society's outcomes instrument 22 ( SRS-22) HRQL questionnaire before treatment. The patients were categorized into thFee groups: a mild deformity group with a major curve Cobb angle less than 30° ( n =14),a moderate deformity group with Cobb angles of 30° to 50° ( n =42), and a severe deformity group with Cobb angles more than 50° ( n =6). Results The severe deformity group scored lowest in the self-image domain.There was,however,no significant difference in the functional activity,pain or mental health domain scores between the three groups. Conclusions The Chinese version of the SRS-22 HRQL questionnaire can be used to assess the HRQL of Chinese AIS patients.AIS patients with a major curve Cobb angle more than 50° have relatively low self-image scores. Key words: Adolescent idiopathic scoliosis ; Assessment ; Quality of life ; Questionnaires

Instrumentation Constructs in Pediatric Patients Undergoing Deformity Correction Correlated With Scoliosis Research Society Scores

Data collected prospectively from the Prospective Pediatric Scoliosis Study (PPSS) were analyzed statistically to address the hypothesis that covered specific aspects of treatment and its outcome. To assess and contrast Scoliosis Research Society (SRS) outcome scores for patients assigned to one of three types of spinal instrumentation constructs. The study hypothesis was that the instrumentation strategy that provides the best curve correction will be associated with the best SRS scores. Surgical treatment of scoliosis has evolved over time using implants and surgical techniques; however, quality of life indicators have not typically been analyzed to assess whether surgery and instrumentation will improve quality of life in pediatric patients. Patients were assigned to one of three instrumentation groups depending on the type of construct used. The Scoliosis Research Society's SRS-30 survey was used to measure patient outcomes comparing preoperative results to a 2-year follow-up. Changes in the SRS Pain, Activity, Appearance, Mental, Satisfaction, and SRS Total domains did not differ significantly among instrumentation groups for any time intervals. However, analysis of SRS Pain did show a significant change over time for all instrumentation patterns. The analysis of SRS Activity showed a significant change over time for all instrumentation patterns preoperatively to 2 years postoperatively. Analysis of SRS Appearance showed a significant change over time for all groups but no difference between instrumentation groups. The analysis of SRS Mental based on instrumentation types showed a significant change over time, but only the pedicle screw group's change was statistically significant. Finally, analysis of SRS Satisfaction by instrumentation type showed a statistically significant change over time for all instrumentation patterns. There were no statistically significant baseline differences among the three instrumentation construct groups based on mean scores for the six SRS domains. None of the SRS domains had differences among the instrumentation constructs in change scores or significant differences among the instrumentation constructs.

Validation and Clinical Relevance of a French-Canadian Version of the Spinal Appearance Questionnaire in Adolescent Patients

Prospective validation study of a crosscultural adaptation of the Spinal Appearance Questionnaire (SAQ). To provide a French-Canadian version of the SAQ. The SAQ is widely used for the assessment of appearance in adolescent idiopathic scoliosis patients. French translation/back-translation of the Spinal Appearance Questionnaire-French version (SAQ-fv) was done by an expert committee. Its reliability was measured using the intradomain correlation coefficient, concurrent validity by using the Scoliosis Research Society (SRS) Outcomes Questionnaire, and discriminant validity using analysis of variance, on 182 consecutive patients attending a scoliosis clinic. Intradomain correlations were weak to excellent (ρ = 0.34-0.76, P < 0.01), indicating that the scales' items demonstrated a satisfactory internal coherence. Scores comparison between SAQ-fv items and SRS Outcomes Questionnaire domains showed weak to moderate correlations (ρ = 0.35-0.53, P < 0.01) for the self-image domain, as expected in this test of convergent validity. A clear gradient in SAQ-fv scores according to Cobb angles was found in every domain, and patients' perception of their rib prominence was significantly related to the rib hump measurement, showing good discriminant validity. Body mass index, age, Risser, and gender did not influence the questionnaire scores. Preoperative patients' and parents' scores were significantly more affected when compared with other groups (observation, braced, and postoperative). Distribution of scores in the first section of the questionnaire shows a positive skew toward the wellbeing end of the response scales. However, the other section shows an inversed bell-shape distribution. The SAQ-fv showed satisfactory reliability and validity in French-Canadian adolescents with different severity of idiopathic scoliosis. Spinal deformity appearance evaluation using this tool was found to be independent of patient's general characteristics. In addition, the SAQ-fv is able to discriminate between relevant clinical values, thus providing useful information for the clinical management of adolescent idiopathic scoliosis patients.

Patient Self-Assessment of Appearance Is Improved More by All Pedicle Screw Than by Hybrid Constructs in Surgical Treatment of Adolescent Idiopathic Scoliosis

A multicenter prospective cohort study. To compare the effect of all pedicle screw versus hybrid constructs on patient self-assessment of appearance after posterior spinal fusion with instrumentation for adolescent idiopathic scoliosis (AIS). This will contribute to future cost-effective analyses on surgical management of AIS. For surgical management of AIS, the Spinal Appearance Questionnaire (SAQ) and the Scoliosis Research Society outcomes instrument (SRS-30) are reliable surveys of patient satisfaction, but neither tool has been used to assess outcome by implant type. Patients received either all pedicle screws or hybrid instrumentation. Self-assessment of appearance pre- and after surgery was measured by SAQ and SRS-30. Statistical significance was evaluated through P values (P < 0.01 in the SAQ, P < 0.05 in the SRS-30) and effect sizes. There were 93 patients in the all pedicle screw cohort and 61 in the hybrid cohort. There were no significant preoperative differences between the cohorts in the SAQ or SRS-30. All pedicle screw patients tended to see more improvement in shoulder level than hybrid patients in 2 separate SAQ questions (P = 0.025, Cohen's D = 0.20; P = 0.013, D = 0.24). The screw patients also tended to have better scores than hybrid patients in the category, "looking better in clothes" (P = 0.017, V = 0.24) at 2 years postoperative. All pedicle screw patients self-reported significant greater improvement than hybrid patients in the SRS-30 Appearance and Mental domains (P = 0.016, ES = 0.038; P = 0.005, ES = 0.051). There were no significant differences between cohorts in age, gender, baseline curve, or major curve magnitude. All pedicle screw constructs lead to better self-assessment of appearance in operative treatment of AIS, as determined by SAQ and SRS-30.

Pedicle subtraction osteotomy for rigid kyphosis of the dorsolumbar spine

Pedicle subtraction osteotomy is one of the well established and popular techniques for kyphosis correction. 52 patients with dorsolumbar kyphosis followed up for a minimum period of 2 years after pedicle subtraction osteotomy were assessed prospectively for clinico-radiological and functional outcomes. Unacceptable cosmesis and severe back pain were the chief complaints preoperatively. The average kyphosis at last follow-up was 8.4° compared to preoperative kyphosis of 58°. Union at the osteotomy site was achieved in all patients, and there were no major neurological complications. All patients showed a significant improvement in all subsets of Scoliosis Research Society (SRS-30) outcome measures following the surgery. A greater degree of kyphosis correction (>40°) can be obtained with a single pedicle subtraction osteotomy at the dorsolumbar level with minimal neurological complications.

The Relationship Between Deformity Correction and Clinical Outcomes After Thoracoscopic Scoliosis Surgery

Prospective clinical case series of 100 patients receiving thoracoscopic anterior scoliosis correction. To evaluate the relationship between clinical outcomes of thoracoscopic anterior scoliosis surgery and deformity correction, using the Scoliosis Research Society (SRS) outcomes instrument. Surgical treatment of scoliosis is quantitatively assessed in the clinic, using radiographic measures of deformity correction and the rib hump, but it is important to understand the extent to which these quantitative measures correlate with self-reported improvements in patients' quality of life after surgery. A series of 100 consecutive adolescent idiopathic scoliosis patients received a single anterior rod via a thoracoscopic approach at the Mater Children's Hospital, Brisbane, Australia. Patients completed SRS outcomes questionnaires before surgery and at 24 months after surgery. Multiple regression and t tests were used to investigate the relationship between SRS scores and deformity correction achieved (radiographic measurements and rib hump) after surgery. There were 94 females and 6 males with a mean age of 16.1 years. The mean Cobb angle improved from 52° before surgery to 25° after surgery (52%) and the mean rib hump improved from 16° to 8° (51%). The mean total SRS score for the cohort was 99.4/120. None of the deformity-related parameters in the multiple-regression were significant. However, patients with the lowest postoperative major Cobb angles reported significantly higher SRS scores than those with the highest postoperative Cobb angles, but there was no difference on the basis of rib hump correction. There were no significant differences between patients with either rod fractures or screw-related complications compared to those without complications. Patients undergoing thoracoscopic anterior scoliosis correction reported good SRS scores which are comparable with those in previous studies. Postoperative major Cobb angle is a significant predictor of patient satisfaction when comparing subgroups of patients with the highest and lowest postoperative Cobb angles.

Surgical Treatment of Main Thoracic Scoliosis with Thoracoscopic Anterior Instrumentation

The surgical outcomes in patients with scoliosis at two years following anterior thoracoscopic spinal instrumentation and fusion have been reported. The purpose of this study was to evaluate the results at five years. A consecutive series of forty-one patients with major thoracic scoliosis treated with anterior thoracoscopic spinal instrumentation was evaluated at regular intervals. Prospectively collected data included patient demographics, radiographic measurements, clinical deformity measures, pulmonary function, an assessment of intervertebral fusion, and the scores on the Scoliosis Research Society (SRS-24) outcomes instrument. Perioperative and postoperative complications were recorded. Patient data for the preoperative, two-year, and five-year postoperative time points were compared. In addition, a univariate analysis compared selected two-year radiographic, pulmonary function, and SRS-24 data of the study cohort and those of the patients lost to follow-up. Twenty-five (61%) of the original forty-one patients had five-year follow-up data and were included in the analysis. Between the two-year and five-year follow-up visits, no significant changes were observed with regard to the average percent correction of the major Cobb angle (56% +/- 11% and 52% +/- 14%, respectively), average total lung capacity as a percent of the predicted value (95% +/- 14% and 91% +/- 10%), and the average total SRS-24 score (4.2 +/- 0.4 and 4.1 +/- 0.7). Radio-graphic evaluation of intervertebral fusion at five years revealed convincing evidence of a fusion with remodeling and trabeculae present at 151 (97%) of the 155 instrumented motion segments. No postoperative infections or clinically relevant neurovascular complications were observed. Rod failure occurred in three patients, and three patients required a surgical revision with posterior spinal instrumentation and fusion. Thoracoscopic anterior instrumentation for main thoracic idiopathic scoliosis results in five-year outcomes comparable with those reported previously for open anterior and posterior techniques. The radiographic findings, pulmonary function, and clinical measures remain stable between the two and five-year follow-up time points. Thoracoscopic instrumentation provides a viable alternative to treat spinal deformity; however, the risks of pseudarthrosis, hardware failure, and surgical revision should be considered along with the advantages of limited muscular dissection and improved scar appearance.

Dissecting the Effects of Spinal Fusion and Deformity Magnitude on Quality of Life in Patients With Adolescent Idiopathic Scoliosis

A retrospective review of scores from the Scoliosis Research Society outcomes instrument (SRS-24 questionnaire). To quantify the isolated effects of spinal fusion and deformity magnitude on quality of life in patients with adolescent idiopathic scoliosis (AIS). Significant improvements in 2-year postoperative SRS-24 questionnaire scores have been reported despite the loss of spinal motion due to instrumentation and arthrodesis. As deformity reduction may influence patient perception, it has been difficult to isolate the effect of spinal fusion on quality of life after scoliosis surgery. SRS-24 scores were compared between 3 cohorts of AIS patients (preoperative, postoperative, and nonoperative) using an ANOVA (P < 0.05) to determine the isolated effects of spinal fusion and deformity magnitude. Preoperative SRS-24 scores were collected from a group of patients with preoperative major Cobb angles greater than 40 degrees (n = 194). Postoperative SRS-24 scores were collected from patients with preoperative major Cobb angles greater than 40 degrees and 2-year postoperative major Cobb angles between 20 degrees and 40 degrees (n = 196). Finally, SRS-24 scores were collected from a nonoperative group of patients with major Cobb angles between 20 degrees and 40 degrees (n = 112). Spinal fusion was found to have a negative isolated effect on the Activity domain (-0.3) and on the Total score (-0.2) (P = 0.001) of the SRS-24 questionnaire (score range: 1-5). A smaller deformity magnitude, on the other hand, was found to have a significantly positive isolated effect on all 4 preoperative domains (P < 0.001) and on the Total score (P < 0.001). The combined effect of surgery (spinal fusion and deformity correction) was found to be significantly positive for the Total score (P < 0.001) and for the domains of Pain, Self-Image, and Function (P < 0.001). Spinal fusion has an isolated negative effect on AIS patients' quality of life (Total score) mostly due to a decrease in scores of the Activity domain. The overall positive effect of surgery depends on the individual effects of spinal fusion (slight reduction in quality of life) and deformity reduction (modest improvement in quality of life).

Adapted Simplified Chinese (Mainland) Version of Scoliosis Research Society-22 Questionnaire

Validation study to define validity and reliability of an adapted and translated questionnaire. This study attempted to validate the traditional Chinese (Hong Kong) version of the modified Scoliosis Research Society (SRS) Outcomes Instrument, SRS-22, into simplified Chinese for use in mainland China. Although a traditional Chinese (Hong Kong) adaptation of the SRS-22 has been previously validated, no culturally adapted, validated SRS-22 exists for use in mainland China. Adhering to International Quality of Life Assessment Project guidelines, the adapted traditional Chinese SRS-22 was translated into simplified Chinese while referencing the original English questionnaire. To examine the psychometric properties and clinical application of the adapted simplified Chinese SRS-22, a survey was conducted in a group of randomly selected 87 patients previously surgically treated at an outpatient clinic. Reliability assessment of the simplified Chinese version of the SRS-22 was determined by calculating Cronbach's alpha and intraclass coefficient (ICC) values. Concurrent validity was evaluated by comparing SRS-22 domains with relevant domains of the simplified Short-Form-36 questionnaire; correlation was made using Pearson correlation coefficients. Cronbach's alpha, applied to each of the 22 questions of the adapted SRS-22, revealed very satisfactory internal consistency (Cronbach's alpha = 0.80-0.89) for function/activity and pain, and good consistency (Cronbach's alpha = 0.50-0.79) for the remaining domains. The test/retest reproducibility was found to be good (ICC > or =0.40-0.75) in the function/activity domain, and excellent (ICC > or =0.75) in the remaining domains. In terms of concurrent validity, 3 domains had excellent correlation, while 10 had good correlation, and 21 had moderate correlation. The authors report the validation of a simplified Chinese SRS-22 for use in mainland China, which is culturally relevant, reliable, repeatable, psychometrically sound, and suitable for immediate clinical use.

Pedicle Screw Instrumentation for Adult Idiopathic Scoliosis

A matched cohort comparison of adult idiopathic scoliosis (AdIS) patients treated with all pedicle screw constructs compared to hook/hybrid constructs. To compare clinical and radiographic results of AdIS treatment using all pedicle screw constructs versus hook/hybrid constructs. Pedicle screw instrumentation has demonstrated excellent clinical efficacy in the treatment of pediatric spinal deformity. No prior reports have compared the outcomes of pedicle screw only constructs to hook/hybrid constructs in the treatment of AdIS. We analyzed 34 consecutive patients undergoing posterior-only correction for AdIS, using pedicle screw instrumentation at minimum 2-year follow-up. Thirty-four matching patients (11 with anterior releases) were selected from a cohort of 58 patients treated with hook/hybrid constructs based on similar age, curve type, magnitude, and fusion levels. Significantly greater curve correction was seen in the pedicle screw compared to the hook/hybrid group (56 vs. 40%, P < 0.01). Coronal and sagittal imbalance were equivalent between the groups (P = 0.91 and 0.23, respectively). Thoracic kyphosis (T5-T12) was maintained in the pedicle screw patients but significantly increased in the hybrid/hook patients over time (P < 0.05). Scoliosis Research Society outcome scores significantly improved in both groups. Blood loss was equivalent but operative time was longer in the hook/hybrid patients.No pedicle screw patients were revised for instrumentation complications with 1 lumbosacral nonunion revised at 5 years postoperative (3% revision rate). Eight of 58 patients among the hook/hybrid cohort underwent 9 revisions for instrumentation failure (n = 3) or nonunion (n = 6) (14% revision rate; P = 0.04). Pedicle screw correction of AdIS is safe and effective. Compared to hook/hybrid constructs, these patients displayed significantly improved correction of the major curve (even in the absence of anterior releases), maintenance of thoracic kyphosis, and a lower revision rate. Similar SRS scores and blood loss were noted. The hook/hybrid patients had significantly longer operative times. The use of BMP-2 in 7 patients and TLIF/ALIF also in 7 of the pedicle screw patients may have decreased the need for revision surgery up to the latest follow-up.

Reliability and Validity of Adapted French Canadian Version of Scoliosis Research Society Outcomes Questionnaire (SRS-22) in Quebec

Prospective validation study of a cross-cultural adaptation of the Scoliosis Research Society (SRS) Outcomes Questionnaire. To provide a French Canadian version of the SRS Outcomes Questionnaire and to empirically test its response in healthy adolescents and adolescent idiopathic scoliosis (AIS) patients in Québec. The SRS Outcomes Questionnaire is widely used for the assessment of health-related quality of life in AIS patients. French translation and back-translation of the SRS-22 (SRS-22-fv) were done by an expert committee. Its reliability was measured using the coefficient of internal consistency, construct validity with a factorial analysis, concurrent validity by using the short form-12 and discriminant validity using ANOVA and multivariate linear regression, on 145 AIS patients, 44 patients with non clinically significant scoliosis (NCSS), and 64 healthy patients. The SRS-22-fv showed a good global internal consistency (AIS: Cronbach alpha = 0.86, NCSS: 0.81, and controls: 0.79) and in all of its domains for AIS patients. The factorial structure was coherent with the original questionnaire (47.4% of explained variance). High correlation coefficients were obtained between SRS-22-fv and short form-12 corresponding domains. Boys had higher scores than girls, scores worsened with age, and with increasing body mass index. Mean Total, Pain, Self-image, and Satisfaction scores, were correlated with Cobb angle. Adjusted regression models showed statistically significant differences between the AIS, NCSS, and control groups in the Total, Pain, and Function scores. The SRS-22-fv showed satisfactory reliability, factorial, concurrent, and discriminant validity. This study provides scores in a significant group of healthy adolescents and demonstrates a clear gradient in response between subjects with AIS, NCSS, and controls.

Video-Assisted Anterior Thoracoscopic Spinal Fusion Versus Posterior Spinal Fusion

Retrospective, matched cohort. The purpose of this study was to compare the Scoliosis Research Society's Outcomes measures (SRS-22) scores, as well as radiographic outcomes of patients with adolescent idiopathic scoliosis who had a single thoracic structural curvature treated by either posterior spinal fusion (PSF) or video-assisted thoracoscopic (VATS) fusion. To our knowledge, there has been no prior matched-pair study comparing outcomes between 2 different surgical approaches for the same curve type using the SRS-22 outcomes instrument. Patients were evaluated before surgery and at 2-year follow-up. A total of 52 patients with Lenke type I curvature were paired by age, gender, and major Cobb angle into 2 groups: PSF (8 men, 18 women, mean age 14.7, mean Cobb angle 48.7) and VATS (mean age 14.8, mean Cobb angle 49.1). All questionnaire scores were classified based on domains of activity, pain, self-image, mental health, satisfaction, and total scores. The patients in the VATS group scored higher than the PSF group in the domains of self-image (P < 0.02), mental health (P < 0.03), and total score (P < 0.05), but not activity, pain, or satisfaction at 2 years. There was no difference in percent curve correction between the match-paired groups. Within-group analyses revealed that VATS patients experienced insignificant improvements compared with PSF in most SRS-22 domains and a trend toward significant overall mean score improvement (P = 0.06). Based on the SRS-22 questionnaire data, the VATS patients scored higher in the self-image, mental health, and total domains despite similar curve corrections. We hypothesize that this may be related to the smaller surgical scar and less invasive nature of VATS.