Posterior Hemivertebra Resection

A hemivertebra is an extra, wedge-shaped half-vertebra. Because it is taller on one side than the other, it forces the spine to tilt and curve at that point, and as the child grows the curve above and below it tends to grow worse. Unlike the more common adolescent scoliosis, a congenital curve caused by a hemivertebra will often not respond to a brace, because the problem is a fixed, structural abnormality of the bone rather than a flexible curve. The rationale for surgery is therefore to remove the cause of the curve — the hemivertebra itself — and to correct the deformity before it becomes large and rigid and before it drags neighbouring parts of the spine into secondary curves. Removing the abnormal segment early, while the curve is still short and the child small, generally allows a shorter fusion and a better long-term shape. This is why the operation is often considered in young children, frequently between about one and six years of age.

This is what is generally done, although techniques vary between surgeons and centres. The whole operation is carried out through the back — a single, posterior approach — which avoids the need for a separate operation through the chest or abdomen. The spine is exposed at the level of the hemivertebra, and small anchors (usually pedicle screws) are placed into the healthy vertebrae immediately above and below it. The abnormal half-vertebra, together with its disc above and below, is then carefully removed, which closes down the wedge and takes away the driver of the curve. The gap that remains is gently closed using the screws and a short rod on each side, straightening the spine, and bone graft is added so that the two healthy vertebrae fuse together into one solid, well-aligned block over the following months. Because the operation is close to the spinal cord and nerves, they are monitored throughout. This technique — pioneered by Ruf and Harms — is often described as a short-segment fusion, because only a small number of levels need to be joined, preserving movement elsewhere in the spine.

Posterior hemivertebra resection with short-segment pedicle-screw fixation is now regarded as the mainstream, well-established treatment for congenital scoliosis due to a single hemivertebra. Across many published series it achieves substantial correction — commonly in the region of 60 to 85 percent of the segmental curve — with good restoration of the spine's balance and often some spontaneous improvement of the compensatory curves above and below. Long-term studies with follow-up of five to ten years show that the correction is generally well maintained, and that doing the operation early tends to give the best shape. It is considered a safe operation in experienced hands, with a low rate of lasting nerve injury; the complications most often reported are related to the implants — such as a screw loosening or a rod breaking — and occasionally some gradual loss of correction or a need for further surgery as the child grows. The overall message from the literature is that early single-stage posterior resection reliably corrects the deformity while fusing only a short segment.

Recovery in a young child is usually quicker than families expect, and the team supports the family throughout. Children often begin to get up and move within about a day of the operation. A protective brace or jacket is commonly worn for a period — frequently around three months — while the short fusion becomes solid, and the exact plan depends on how secure the fixation is. The hospital stay is typically a few days. Over the following weeks children generally return to normal play and activity as comfort allows, and because only a short segment is fused, most movement of the spine is preserved. The spine is then followed up with periodic reviews and X-rays as the child grows, to check that the correction holds and that no new curve develops. It is normal for the curve to look dramatically straighter soon after surgery and for the long-term shape to be monitored over years.

As with any spinal operation near the nerves, this surgery carries risks that the team discusses fully beforehand. These can include bleeding, infection, and — uncommonly — injury to the nerves, which is why the spinal cord is monitored during the operation. Implant-related problems such as loosening or breakage, and gradual loss of correction or the emergence of a new curve as the child continues to grow, are the issues most often needing further attention. Because congenital spine problems can be associated with abnormalities elsewhere, children are usually checked carefully before surgery. This page is educational and does not recommend or advise for or against surgery in any individual case.

• —Ruf M, Harms J. Posterior hemivertebra resection with transpedicular instrumentation: early correction in children aged 1 to 6 years. (PMID 14501925)
• —Zhuang Q et al. Posterior hemivertebra resection and short-segment fusion with pedicle screw fixation for congenital scoliosis in children younger than 10 years: greater than 7-year follow-up. (PMID 25835484)
• —Hemivertebra resection and spinal arthrodesis by single-stage posterior approach: results at 9.6 years mean follow-up. (PMID 35177526)
• —Surgical outcomes and complications of posterior hemivertebra resection in children younger than 5 years old. (PMID 27113726 / PMC4845311)
• —Clinical and radiological outcomes of hemivertebra resection for congenital scoliosis in children under age 10: more than 5-year follow-up. (PMID 32769940 / PMC7593047)
• —Posterior-approach lumbar and thoracolumbar hemivertebra resection in children under 10: results at 3 years mean follow-up. (PMID 23934348 / PMC3897828)
• —The efficacy and complications of posterior hemivertebra resection. (PMC3175869)
• —The results of hemivertebra resection by the posterior approach in children with a mean follow-up of five years. (PMC5661088)
• —Posterior hemivertebra resection with unilateral instrumented fusion in children less than 10 years old: minimum 5-year follow-up. (PMC6149002)
• —Efficacy and safety of one-stage posterior hemivertebral resection for unbalanced multiple hemivertebrae. (PMID 28727996)
• —The radiological outcomes of one-stage posterior-only hemivertebra resection and short-segment fusion for lumbosacral hemivertebra: minimum 5 years. (PMC6907193)
• —Individualized study of posterior hemivertebra excision and short-segment pedicle screw fixation for congenital scoliosis. (PMC7862179)
• —Analysis of factors affecting loss of correction after one-stage posterior hemivertebra resection and fusion. (PMC10712081)
• —Congenital scoliosis: a narrative review and proposal of a treatment algorithm. (PMC9142820)
• —Current concepts — congenital scoliosis. (PMC5447938)