Mid-term outcomes of one-stage posterior-only jumping hemivertebra resections and short fusions for children with congenital scoliosis secondary to multiple hemivertebrae / 中华骨科杂志

ABSTRACT

Objective:To evaluate the safety and efficacy of one-stage posterior-only jumping hemivertebra (HV) resection combined with respective short fusions in the treatment of congenital scoliosis (CS) caused by multiple HVs.Methods:All of 13 consecutive patients with multiple HVs treated surgically from January 2010 to December 2017 were retrospectively reviewed, including 4 males and 9 females with a mean age of 3.7±1.2 years. One child had 4 HVs, and the rest had 2 HVs. The responsible HVs causing local scoliosis/kyphosis deformity or coronal plane deviation were selected as the target of resection. The distal HV was removed firstly and then the proximal one was resected; both of the fixation vertebraes were horizontalized during surgery. The clinical and imaging data of the children before the initial operation, immediately after the operation and at the latest follow-up were collected, and the short-term and long-term complications related to surgery were recorded. The data were evaluated on the whole-standing spine anteroposterior and lateral films, including the corrections of proximal and distal main curves, coronal balance, local kyphosis, and the improvement of spinal growth height (upper and lower internal fixation length, T 1-S 1 length). At the same time, the re-progression of coronal and sagittal deformities of the spine during growth was recorded (coronal decompensation emerging postoperative curve progression more than 20°; kyphosis progression kyphosis aggravation between upper and lower internal fixation more than 40°) and internal-fixation-related complications (screw cutting, screw malposition) were recorded. Results:Dual HVs were resected in each child, of which 8 (61.5%) were located on contralateral side of the spine, and 5 (38.5%) were located on ipsilateral side of the spine. The follow-up time was 6.2±3.3 years (range 2.0-10.5 years) after surgery. The Cobb angles of proximal and distal main curves were 36.7°±11.8° and 35.2°±7.8° respectively before surgery and were corrected to 9.7°±6.6° and 6.1°±4.1° respectively after surgery ( F=31.249, F=93.83, P< 0.001) ( t=6.888, t=10.954, P<0.001), and the correction rates was 73.6%±19.6% and 82.7%±11.7%, respectively. They were maintained at 14.3°±5.4° and 8.0°±4.6° at the latest follow-up, showing the correction rates loss of 15.8%±26.9% and 6.9%±7%, respectively. The coronal balance improved from 17.2±14.8 mm pre-operatively to -0.2±15.7 mm postoperatively ( t=2.703, P=0.008), and it remained at 0±18.4 mm at the final follow-up ( F=4.137, P=0.024). The T 1-S 1 length was corrected to 273.8±27.3 mm postoperatively, slightly increased compared with pre-operation 256.3±24.0 mm, ( t=0.680, P=0.527), and significantly increased to 333.2±33.4 mm at the latest follow-up ( t=2.986, P<0.001; F=6.704, P=0.003). Seven patients had local kyphosis before operation, which was significantly improved from 32.2°±13.6° to 6.1°±9.8° with a correction rate of 93.4%±27.0% after surgery ( t=3.355, P=0.004), which showed no significant loss of correction at the latest follow-up (5.4°±10.4°) ( F=11.187, P=0.002). Six patients (46.2%) developed coronal decompensation (Curve magnitude >20 °), with an average of 21.7°±1.9°. Two cases (15.4%) had progressive kyphosis between the thoracic regional internal fixations at 3 months after surgery, which were 68° and 58° respectively. After bracing, both coronal decompensation and sagittal kyphosis were improved. At the last follow-up, the coronal decompensation was improved to 14.7±8.9° and the kyphosis was alleviated to 55° and 46°, respectively. Conclusion:Posterior-only skipping hemivertebra resection and short fusion is a safe, effective procedure yielding significantly improvement of the growth imbalance and reginal spinal deformities of CS with multiple HVs. The mid-term follow-up results showed that the progress of the scoliosis was common during the growth period, which could be further controlled by supplementary brace treatment.