Adolescent idiopathic scoliosis is a structural 3-dimensional deformity of the spine and trunk that occurs in otherwise healthy children aged 10-18 years old. This is the most common form of scoliosis [1]. Historically, Cobb angle more than 50° is the indication for surgery, but this limit of Cobb angle varies greatly within the surgical community. Severe rigid idiopathic scoliosis is described as [2].

The management of severe rigid deformities has always been a major challenge to spine surgeons. There is a high risk of permanent of transient neurologic injury in the surgical correction for severe rigid scoliosis. Usually the spine surgeon use conventional staged surgery that performed first stage procedure anterior release then second stage posterior spinal fusion and instrumentation [3]. In recent years, posterior vertebra collum resection is used to treat severe and rigid scoliosis, and a correction rate of 51% to 59% can be achieved [4].

Single-stage operation in rigid scoliosis will decrease morbidity in patients The cantilever bending technique provides powerful corrective forces for overcoming the rigidity of the deformity and with this technique will decrease the need for anterior release procedures. There are some significant psychological consequences in treating patient with idiopathic adolescent scoliosis. Adolescence patients need some degree of adaptation when they had a chronic illness because of their sensitive phase of person’s development [1].

The purposes of this study was to evaluate radiological, clinical, and functional outcome patients with severe and rigid scoliosis in Sardjito General Hospital treated with a single-stage operation with Cantilever operation technique.

This was a descriptive analytical study was conducted in patients with scoliosis were treated with operatively with posterior stabilization (cantilever bending technique) that came to Orthopaedic and Traumatology department of Sardjito Hospital from January 2015 – December 2016. Data measured were radiologic parameter (Cobb Angel), enhancement body height and functional outcome were measured by and non-radiologic parameter asBarthel Index Figure 1 [5], Instrumental Activities of Daily Living (IADL) Figure 2 [6], Rosenberg Self-Esteem Scale (Table 1) [7].

Cobb angle was used in this study to quantify the magnitude of spinal deformities. It was used as a standard measurement to determine and track the progression of scoliosis. To evaluate the cobb angle, firstwe decided which vertebrae were the end-vertebrae of the curve deformity (vertebrae at the upper and lower limits of the curve) and the cobb angle was defined by the intersection of the two lines (line that parallel to the end plate of the superior end vertebrae and another line that parallel to the endplate of the inferior end vertebrae). Severe and rigid scoliosis was defined if the patient has cobb angle more that 70 degrees.

There were seven eligible subjects from January 2015 – December 2016. Six females aged 13–18 years old, one male aged 14 years old (Figures 3,4,5,6,7,8,9). We performed single-staged operation in the operating theatre setting. Cobb angle decrease from 85o to 35o, 75o to 35o, 72o to 25o, 82o to 30o , 98o to 47o and 82o to 45o. Increasing body height with result 145 cm to 150 cm, 150 cm to 154 cm, 149 cm to 151 cm, 145 cm to 150 cm, 147 cm to 153 cm, 126 cm to 139 cm, 142 cm to 147 cm, with mean increase about 2–6 cm post operatively. There were statistically significant differences functional outcome in Barthel Index, Activities of Daily Living and Rosenberg Self-Esteem Scale pre-operative and post-operative treatment using paired T-test (P<0.001) (Figures 10,11,12). Only one patient seems not require ICU treatment. Despite this successful outcome, one of the patient suffered from pulmonary problem requiring respiratory and pulmonary support in the ICU. This patient was discharged 26 days after operation. Seven other patient were discharged in 2 until 4 days post operation.

According to Silva et al, severe rigid idiopathic scoliosis is described as [2]. Only one of our patients have Cobb angle > 90o, the chief complain was asymmetrical shoulder with moderate pain.

The therapeutic of scoliosis is influenced by many factors, such as the age, type and severity of deformity, spine flexibility, and combined other deformities. Severe scoliosis is more difficult to treat than usual ones. It is difficult to complete the correction, and the probability of nerve deficit increases. The operation is of relatively high risk, because it is usually combined with heart or lung dysfunctions [3]. In our patient, there was no pulmonary problem preoperatively in all of them.

The treatment of severe and rigid scoliosis brings great challenge to surgeons, and various kinds of correction methods are developed. Shen et al. published a series of 24 patients operated with anterior release and posterior hooks and pedicle screws, with a preoperative Cobb angle of 98.8° and a Cobb angle of 68.0° on preoperative bending films, they achieved a final curve correction of 58.6% [8]. Watanabe et al reported total of 21 scoliosis patients with ≥100° curves use perioperative halo-gravity traction before underwent spinal instrumentated fusion. He reported 27.5% correction of the major curve Cobb angle with preoperative traction and 37.2% correction with staged traction after anterior release [9]. Suk et al. reported a series of 16 patients with severe scoliosis treated with posterior vertebra collum resection. The preoperative average major curve of 109 was corrected to 45.6, showing a 59% of scoliosis correction [10].

In our study we did the posterior approach only with Cantilever bending technique without anterior release. The Cantilever method has some biomechanical advantages with powerful correctives for the rigidity of the deformity so we can avoid performing anterior release procedure.[11] . The major indication for additional anterior release was large (70°) and rigid curvature (30% compensation on lateral -bending radiographs). The anterior release procedure is often used to lessen the rigidity of the deformity and to improve the correctability of the spine with Cantilever technique we achieve correction 30o until 50o and the functional outcome were good.

This study showed that single-stage operation with Cantilever technique was beneficial, important, complex, and need team approach for the treatment in severe and rigid scoliosis. The functional outcome of patient with idiopathic scoliosis treat operatively with posterior stabilization by Cantilever operation technique in Sardjito hospital is good based on Cobb Angle, Barthel Index, Instrumental Activities of Daily Living (IADL), Rosenberg Self-Esteem (RSE) Scale and body height evaluation.