Average Main Curve Research Articles

Multiple Hemivertebrae: The Natural History and Treatment of 50 Patients

Multiple hemivertebrae (MHV) is defined as three or more hemivertebrae, and is relatively uncommon among patients with congenital scoliosis. This study aimed to compare the natural history of different kinds of MHV and describe the surgical outcome of MHV. In this retrospective cohort study, a total of 50 patients diagnosed with MHV were enrolled from June 2007 to June 2018. The medical records and radiographs of these patients were reviewed to summarize the characteristics of MHV. Patients with MHV were divided into the unbalanced (UB) group, partially unbalanced (PUB) group, and completely balanced (CB) group. Medical records and radiographs of MHV patients were reviewed to collect HV position, natural history, coronal and sagittal parameters. A Mann-Whitney U test was used to compare the radiographical data, such as the cobb angle of main curve and secondary curve, and Fisher's exact test was used to compare the patients in different kinds of MHV with surgical indication or not. The average number of hemivertebrae was 3.6 and the average main curve was 57.5°. Twenty-four of 50 patients had associated anomalies, including four patients with sacral agenesis, one with tetralogy of Fallot, two with congenital imperforate anus, and 17 with Klippel-Feil syndrome. In 22 patients who underwent MRI imaging, three patients had mild syringomyelia and three patients had diastematomyelia. The UB and PUB groups had a larger main curve and compensatory curve than the CB group. Of the 25 patients with follow-up before surgery, the curve progression rate was highest in the UB group (12.1°/year) but similar in the PUB group (4.2°/year) and CB group (3.6°/year). All patients in the UB and PUB group met the criteria for surgery. In contrast, only 10 of 23 patients in the CB group had surgical indications. Eighteen of the 37 patients with surgical indications chose to undergo surgery and the correction rate of the main curve was 51.4%. Early surgical intervention should be considered for most patients with UB or PUB MHV. For patients with CB MHV, surgical treatment may not be urgently needed at the first visit. Posterior hemivertebrectomy could be used for the treatment of MHV with satisfying radiographic outcome.

Intensive bracing management combined with physiotherapeutic scoliosis-specific exercises for adolescent idiopathic scoliosis patients with a major curve ranging from 40-60° who refused surgery: a prospective cohort study.

Current guidelines for brace management of adolescent idiopathic scoliosis (AIS) are mostly recommended for curves between 25° to 40°. For AIS patients with curves >40°, surgery is often considered since bracing may be less effective; however, there are still some patients and families who refuse operation. Therefore, further research is necessary to determine optimal bracing management in this group. To date, few protocols for such have been reported in literature. The aim of this study was to introduce and evaluate the effectiveness of the treatment protocol comprising of intensive bracing management and physiotherapeutic scoliosis-specific exercises (PSSE) in AIS patients with a major curve of 40-60° who refuse surgery. This is a prospective cohort study. The study was carried out in an outpatient clinic. 10-18-year-old AIS patients having 40-60°curves and a Risser grade of 0-3, but firmly refusing surgery were eligible. Patients who had a proximal thoracic curve or had undergone any other form of treatment previously were excluded from the study. A total of 82 patients were recruited and received the treatment. The primary outcome was defined as "success" when the main curve was below 50° upon reaching skeletal maturity, and "failure" if otherwise. The secondary outcome was defined as improved (>5° reduction), unchanged (≤5° change) or progressed (>5° increase) based on the evolution of the main curve. The per protocol (PP) and intent to treat (ITT) analyses were performed to quantify success rates, while the dropouts were considered as failures. Risk factors associated with bracing failure were identified and a receiver operating characteristic (ROC) curve was used to determine the cut-off value. A total of 77 patients completed the treatment, while 5 dropped out. The average main curve was 47.40±5.93° at baseline and 38.56±11.85° at last follow-up (P<0.001). Our management was successful in 83% and 78% of patients based on the PP and ITT analyses, respectively. When compared with the curve magnitude at baseline, 65% patients improved, 30% remained unchanged, and 5% progressed when using a 5° threshold. Univariate comparison and logistic regression analysis demonstrated that patients with successful outcomes had a significantly smaller baseline curve, larger Risser Stage, and larger in-brace correction (IBC) rate. For AIS patients with 40-60° curves who refused surgery, our intensive bracing management along with PSSE was practical and effective, achieving success in 78% of patients based on an ITT analysis. A larger baseline curve, smaller Risser Stage, and smaller IBC rate were associated with treatment failure. Our intensive management provides new insights into improving the effectiveness of bracing in patients with AIS who refuse surgery. This is a promising option for patients with 40-60° curves, since their scoliosis may be treated using a non-surgical technique instead of surgery in the future.

Simultaneous Translation on Two Rods to Treat Adolescent Idiopathic Scoliosis

Retrospective analysis of a consecutive cohort of 62 adolescent patients treated by posterior spinal fusion (PSF) with a minimum follow-up of 2 years. To present sagittal and coronal results of a specific method of reduction: the simultaneous translation on 2 rods (ST2R). The long-term outcome of surgically treated scoliosis is dependent not only on the coronal correction but also on restoration of sagittal curves. Recent publications confirm the moderate correction of thoracic hypokyphosis by posterior instrumentation with hooks or pedicle screws. Radiographic parameters were measured preoperatively and at 6 weeks, 1 year, and last follow-up (between 2 and 7.4 years) in a consecutive cohort of 62 patients with adolescent idiopathic scoliosis (AIS) treated by PSF. All operative procedures were performed by the same surgeon using stable anchorages such as screws or self-stabilizing claws. The screws and claws included a polyaxial-threaded extension, which was fixed to the rod with connecting clamps. Reduction of the deformity was obtained by gradual and alternate tightening of the nuts on all threaded extensions on both rods, which allowed the vertebrae to gradually approach the rods while the translation maneuver was performed. In the coronal plane, the average main curve was reduced from 51° to 16° and maintained 70% of correction at last follow-up. In the sagittal plane, for patients with hypokyphosis (27 cases < 20°), the average kyphosis angle was significantly improved from 9° to 29° and maintained during follow-up (32°) with a mean gain of 23° (P < 0.0001). Only 1 patient reported hypokyphosis (18°) at last follow-up. For patients with normal kyphosis, the average gain was 8°. In a large consecutive cohort, reduction of scoliosis by ST2R is a simple method that allows 70% of correction in the coronal plane, equivalent to screw instrumentations, and a restoration of normal thoracic kyphosis.

Simultaneous translation on two rods is an effective method for correction of hypokyphosis in AIS: radiographic results of 24 hypokyphotic thoracic scoliosis with 2 years minimum follow-up

Recent publications confirm that moderate correction of thoracic hypokyphosis can be achieved by posterior instrumentation with hooks or pedicle screws. Twenty-four prospective and consecutive thoracic adolescent scoliosis patients with hypokyphosis (<20°) were operated on by posterior spinal fusion (PSF) with a specific method of reduction: Simultaneous translation on two rods (ST2R), performed by the same surgeon using stable anchorages such as screws or self-stabilizing claws. Radiographic parameters were measured preoperatively, at 1 month, 1 year and at 2 years minimum follow-up. In the coronal plane, the average main curve was significantly reduced from 51° to 17° and maintained at last follow-up, corresponding to an average correction of 67%. In the sagittal plane, the average kyphosis angle was significantly improved from 9° to 30° postoperatively and to 32° at last follow-up, corresponding to a mean gain of 23°. The 24 patients reported normal kyphosis at last follow-up (≥20°). Reduction of scoliosis by ST2R is an effective method that gives coronal correction equivalent to all screw constructs and allows restoration of normal thoracic kyphosis.