Convex short segment instrumentation and hemi-chevron osteotomies for Putti type 1 thoracic hemivertebrae: a simple treatment option for patients under 5 years old

Correlation between Age and Surgical Approach for Thoracic and Lumbar Hemivertebra

Objective Hemivertebra (HV) is a congenital defect of the formation of the spinal vertebra, which can result in scoliosis or kyphosis along with the related symptomatology of spine deformity. More often than not, it is linked to other abnormalities and requires attention. Its management is surgical and it is of great importance for the physician to choose the right approach at the right time, due to its deteriorative prognosis.

Methods Due to the interest of the subject, the authors investigated the world literature between 1990 and 2018 and found 45 articles, reporting thoracic, thoracolumbar, and lumbar HV in children and its postsurgical outcome, aiming to show whether the approaches are equal in terms of the final outcome.

Results The chosen surgical method depends much on the level of the pathology. Despite this fact, after analyzing the included data, we found that the surgical techniques are unequal with regard to the purpose of achieving improvement. Age, caudal and cranial curves, segmental kyphosis, and scoliosis are factors playing a major role in this.

Conclusion If not treated, HV leads to deterioration and dysfunction. The most optimal result, however, is achieved only when the surgical approach is applied according to age and rest of the accompanying factors, which should be considered in future management planning.

Posterior hemivertebra resection with unilateral instrumented fusion in children less than 10 years old: preliminary results at minimum 5-year follow-up

Background

The main treatment for congenital hemivertebra is posterior hemivertebrectomy with bilateral transpedicular fixation. To date, studies describing posterior unilateral fusion are few, especially in younger children. The modified method by posterior hemivertebrectomy combined with unilateral transpedicular instrumentation and fusion was described. The purpose was to present the clinical and radiological outcome of children less than 10 years treated for congenital scoliosis with posterior hemivertebrectomy and unilateral instrumented fusion.

Methods

A study of 43 consecutive patients through Jan. 2006 to Mar. 2013 for hemivertebrae in children less than 10 years was performed. Patients undergoing hemivertebrectomy and posterior convex short-segment fusion, which had been followed up for at least 60 months, were included. Coronal main curve, kyphosis, T1-S1 height, fused vertebra height, and concave height were measured at preoperation, immediate postoperation, and final follow-up. The outcome and efficacy of the correction provided and growth of the non-fused concave side of the spine was investigated.

Results

The average follow-up period was 73.88 ± 16.77 months. The mean Cobb angle of the coronal curve was improved from 46.1 to 8.1° (correction rate 82.4%). At final follow-up, there was 7.8% loss of correction. The average concave height, fusion segment height, and T1-S1 height were 60.1 ± 19.7 mm, 56.9 ± 22.9 mm, and 326.6 ± 64.5 mm in immediate postoperation, which improved to 73.1 ± 23.7 mm, 71.2 ± 22.0 mm, and 388.7 ± 78.9 mm at the last follow-up. These parameters were significantly different between the immediate postoperation and at final follow-up. The rate of reoperation was 9.3% (4/43), mainly in PJK and curve progression after surgery.

Conclusions

Despite with some complications, posterior hemivertebrectomy and unilateral instrumented fusion are commendable procedures. We concluded that it is a simple, secure, reliable, less-invasive, and well-tolerated technique that can successfully resolve this kind of congenital scoliosis in children.

Risk factors for construct/implant related complications following primary posterior hemivertebra resection: Study on 116 cases with more than 2 years' follow-up in one medical center

Background

Posterior hemivertebra resection has become a safe and effective procedure for congenital scoliosis due to hemivertebra. However, there are still complications following primary posterior hemivertebra resection in recent reports. No risk factors associated with construct/implant related complications were identified so far. The purpose of this study is to analyze complications following primary posterior hemivertebra resection and to investigate the possible risk factors associated with construct/implant related complications in congenital scoliosis cases due to hemivertebra.

Methods

One hundred and sixteen congenital scoliosis cases with hemivertebra (male: female = 62:54), who underwent primary posterior hemivertebra resection from January 2003 to January 2012 in our medical center, were retrospectively evaluated in this study. Medical records were reviewed and long cassette standing spinal radiographs were measured before surgery, after surgery and at the final follow-up. Complications, including construct/implant related complications and non-construct/implant related ones, were recorded by chart review. Potential risk factors, including sex, age, segmental and main scoliosis and their correction rates, usage of cage (yes or not), fusion levels (bisegmental fusion or not), location of hemivertebra and contralateral bar/rib synostosis (with or without), were also collected.

Results

The mean age of initial surgery was 9.8 years old (range, 2–19 years), and the average follow-up was 67 months (range, 24–133 months). The segmental scoliosis was corrected from 34.7° ± 11.9° to 7.1° ± 5.6° post-operatively, and 9.5° ± 7.0° at the latest follow-up, with a correction rate of 79.5 %. The total main scoliosis was corrected from 43.0° ±15.6° to post-operative 11.4° ± 6.8°, and 13.9° ± 7.5° at the latest follow-up, with a mean correction rate of 73.5 %. Complications occurred in 11 out of 116 cases (9.5 %), including 7 (63.6 %) construct/implant related complications (two pedicle misplacement, one rod breakage and four implant removals due to screw dislodgement with the growth) and 4 (36.4 %) non-construct/implant related ones (one proximal adjacent kyphosis, one progressive kyphosis, and two wound non-union). Younger age (≤5 years old), lumbar hemivertebra resection, or bisegmental fusion may contribute to a higher prevalence of construct/implant related complications than other cases, although the number of cases was too small to perform statistical analysis.

Conclusions

The occurrence of construct/implant related complications in patients with hemivertebra resection is most likely multifactorial. Cases with younger age, bisegmental fusion, or lumbar hemivertebra may increase the risk of construct/implant related complications. Measures, such as careful preoperative evaluation and surgical plan with CT scan, sophisticated operation during surgery, usage of cage or cross-links to improve postoperative instant stability, protection in brace and regular follow-up postoperatively, should be taken to reduce construct/implant related complication rate.