To our knowledge, most studies on congenital kyphoscoliosis or kyphosis concern pediatric patients, there is a minority of research referring to the surgical treatment of severe rigid congenital kyphoscoliosis in adolescence. Most of congenital kyphoscoliosis in adolescence fail to be cured by conservative treatment because of an unacceptable cosmetic appearance, progression of deformity or neurological dysfunction [12–14]. Surgical correction of congenital curves is generally more successful when high-risk curves of a smaller magnitude are treated early. Compare with younger patients, the skeletal of adolescence is the nearly maturity. The delayed treatment of adolescence congenial deformity result in the secondary structural curves and therefore requires long fusion segments. In other word, it is difficulty to correct the rigid curves and associated with a higher risk of neurologic impairment .
The ideal surgical approach for severe rigid congenital kyphoscoliosis in adolescence is controversial. In the past, most surgeons confirmed that one-stage posterior hemivertebra excision with short segmental fusion is a feasible procedure for congenital kyphoscoliosis in patients [16, 17]. Nevertheless, the majority of series were younger patients in whom deformity were mild. It is unknown whether the surgery approach effectively applied in adolescent congenital deformity with rigid and severe kyphoscoliosis. Ruf and Harms  reported that hemivertebra resection by the posterior-only procedure. They reported the good results of their study. However, in the series, most of the patients were children, the spinal deformity fail to become rigid and severe. In 2003, David et al  reported two cases of adults presenting with fully segmented thoracic hemivertebrae who underwent one-stage posterior hemivertebra excision with short segmental fusion. There were no neurological complications. However, the patients present with rigid and mild deformity. In 2011, Li et al  reported that twelve patients with adolescent congenital deformity who underwent posterior unilateral pedicle subtraction osteotomy and short-segment instrumentation. The mean age of the series was 17 years (range, 15–21 years). They considered that the approach could be easily and effectively applied in adolescent congenital deformity with mild and moderate scoliosis. In our series, 12 patients underwent hemivertebra excision and long instrumentation, the mean rates of correction of the major and segmental curves were worse to the reported results of hemivertebra excision in patients. Hence, for severe rigid kyphoscoliosis in adolescence, hemivertebra excision and long instrumentation often fail to effectively correction correct combined deformities. Therefore, the authors adopted a new method, combining hemivertebra resection with wedge osteotomy in only posterior procedure, and this new method is named ‘‘HRWO’’
The posterior osteotomies approaches for the treatment of severe rigid spinal deformities have been performed in the last years. In 1979, Leatherman et al , reported that excellent correction of closing wedge osteotomy for rigid congenital deformity in pediatric patients. They reported a correction of 43% of scoliotic curves postoperatively. However, two patients having transient neurologic deficit. Gertzbein et al  reported “wedge osteotomy”; and Kawahara et al  reported “closing–opening wedge osteotomy.” However, the majority of patients presented mild angular kyphosis. Mehment et al  reported that surgical treatment of congenital kyphoscoliosis in adolescent by posterior multiple chevron osteotomies, multiple concave rib osteotomies and all-pedicle screw instrumentation. Chevron osteotomies were performed at apical segments (three to seven levels) and concave rib osteotomies (five to eight levels). They considered that the approach can effectively correct kyphoscoliosis deformities in adolescent. However, as opposed to the current study, few patients with severe rigid kyphosis caused by congenital spinal deformity was included. Therefore, in this study, we selected kyphoscoliosis cases with coronal or sagittal Cobb’s angle greater than 60° and curve flexibility less than 25%. All patients had a single nonincarcerated hemivertebra. During this procedure, we found that simply HR fail to completely removed of the disc materials located at the concave side, so the adjacent spinal segments remain rigid. We performed wedge osteotomy to removal of partly body of adjacent segments, that is, “V”shaped bone resection of the adjacent vertebral body,including the disc materials located at the concave side and both endplate of adjacent segments to obtain more motivation.
We performed posterior wedge osteotomy improve the flexibility of spine, and the spinal cord fail to be stretched because of shortening the posterior structure. Anterior column reconstruction was performed with titanium mesh in the series. We formed titanium mesh in accordance with anterior column interbody gap after wedge osteotomy and deformity correction. After that, the titanium was inserted in the anterior column interbody gap. It is no shorten the anterior column. The titanium mesh provided immediate anterior stability, and can tolerate compression forces well . The rate of solid fusion was 100% in all series at the last follow-up. No crankshaft phenomenon occurred in the series, and because not only all patients with Risser 4 or 5 which the skeleton nearly mature, but also posterior pedicle screw system.
One major concern of HRWO is the risk for blood loss during the posterior osteotomy. The previous research confirmed that a large bleeding may lead to increase postoperative complications and morbidity rates in spinal osteotomy . The following measures have been taken in order to reduce perioperative blood loss. The subperiosteal dissection was performed during the surgical exposure. The intravenous drip of tranexamic acid were routinely received and the wound are irrigated with tranexamic acid during the operation. In addition, it is critical to use Piezosurgery and bipolar electrocautery to control blood loss. Besides, the controlled hypertension is applied to decrease intraoperative blood loss during the operation. There is another issue to concern is neurological complications which may occur from spinal cord compression, dural strctching or buckling, and subluxation of the spinal column. It is critical to completely disclose nerve roots and dural tube before wedge osteotomy. In addition, the spinal cord monitoring is essential for osteotomy, especially when we performed closure of the wedge bone resection. There were 2 patients occurred MEP changes after closure of the wedge bone resection, but none was permanent. There were lower neurological complications in our cohorts. One possible reason is that anterior column reconstruction was performed with titanium mesh in the series, which have contributed to prevent overshortening of spinal column and dural buckling. Another reason may be that use of piezosurgery and spinal cord and nerve roots were under direct observation during the HRWO.