Anterior Hemivertebrectomy + PSF

A hemivertebra is an extra, wedge-shaped half-vertebra that tilts the spine and drives a curve that usually worsens with growth and does not respond to bracing. The aim of surgery is to remove the abnormal segment and correct the deformity. Historically, and in selected cases still today, this is done through a combined approach — reaching the vertebral body from the front (anteriorly) to remove it, and instrumenting and fusing the spine from the back (posteriorly) to correct and hold the alignment. The combined route can be chosen when the anatomy makes anterior access to the vertebral body advantageous, when the front of the spine needs structural support after the segment is removed — for example when a small cage or graft is used to rebuild the column and prevent over-tilting — or in certain rigid or kyphotic deformities. The underlying goal is the same as any hemivertebra operation: take away the cause of the curve and produce a balanced, stable, well-aligned spine.

This is what is generally done, although techniques vary between surgeons and centres, and the two stages may be performed in one sitting or on separate occasions. In the anterior part, the vertebral body of the hemivertebra is reached from the front — through the chest, the flank or the abdomen depending on the level — and the abnormal body and its adjoining discs are removed. In the posterior part, the spine is exposed through the back, anchors such as pedicle screws are placed into the healthy vertebrae above and below, and the remaining wedge is closed down and corrected using rods, with bone graft laid to achieve fusion. Where the front of the spine has been left with a gap, a structural support such as a small titanium cage or block of bone may be placed to rebuild the column and protect against the spine tipping into imbalance. As with all deformity surgery near the spinal cord, the nerves are monitored throughout, and the child's general health, breathing and blood loss are carefully managed.

Comparative studies show that hemivertebra excision through a combined anterior-and-posterior approach achieves curve correction essentially equivalent to the posterior-only technique — commonly in the region of 55 to 67 percent of the segmental curve — with durable results and a low rate of recurrence. However, the same comparative literature consistently shows that the combined approach involves a second incision, a longer operation, more blood loss and a somewhat higher overall complication rate than the single posterior operation. This is precisely why the posterior-only technique has, in many centres, become the more common choice for a straightforward single hemivertebra. The combined approach retains a role in selected situations — such as rigid deformities, scoliokyphosis, or where structural support of the front column with a cage helps prevent over-correction and imbalance. In very young children, surgeons also watch for the "crankshaft" effect, where continued growth of the front of the spine can gradually change the shape after a posterior fusion, which is one reason anterior surgery is sometimes considered.

Recovery mirrors that of other spinal fusions, with the added consideration of the anterior part of the operation, and the family is supported throughout. If the chest has been entered, a temporary drain may be used for a short time, and breathing is supported and monitored closely early on. Children are helped to get up and move as soon as it is safe, and a protective brace or jacket is commonly worn for a period while the fusion becomes solid. The hospital stay is usually a little longer than for a posterior-only operation because of the combined approach. Over the following months the fusion knits, activity gradually returns to normal, and the spine is followed up with periodic reviews and X-rays as the child grows. Families typically see a much straighter spine soon after surgery, with the long-term shape monitored over the years that follow.

This is major surgery through two approaches, and it carries risks the team discusses fully beforehand. These include bleeding, infection, and — because the operation is near the spinal cord and, at some levels, the chest and great vessels — a range of approach-related risks that the surgical team explains in detail; the nerves are monitored to reduce the risk of injury. Because a second, anterior incision is involved, the combined approach generally carries a somewhat higher complication burden and longer recovery than a posterior-only operation, which is why it is reserved for cases where its particular advantages are needed. This page is educational and does not recommend or advise for or against surgery, or any particular approach, in any individual case.

• —Simultaneous anterior and posterior hemivertebra excision. (PMID 10416395)
• —Hemivertebra excision with short-segment spinal fusion through combined anterior and posterior approaches for congenital spinal deformities in children. (PMID 20647938)
• —Comparison of one-stage anteroposterior and posterior-alone hemivertebra resection combined with posterior correction. (PMID 22144739 / PMC3227350)
• —Hemivertebra resection in children: results after single posterior approach and after combined anterior and posterior approach — a comparative study. (PMID 21910033)
• —Posterior vertebrectomy in kyphosis, scoliosis and kyphoscoliosis due to hemivertebra. (PMID 18043375)
• —Posterior-only hemivertebra resection with anterior structural reconstruction with titanium mesh cage and short segmental fusion for congenital scoliokyphosis. (PMID 28557818)
• —Posterior hemivertebra resection and monosegmental fusion in the treatment of congenital scoliosis. (PMID 24417829 / PMC5137654)
• —Posterior hemivertebra resection with bisegmental fusion: more than 3-year outcomes and analysis of unanticipated surgeries. (PMC3555607)
• —Posterior thoracolumbar hemivertebra resection and short-segment fusion: outcomes and complications with more than 5-year follow-up. (PMC7993516)
• —Surgical outcomes of hemivertebra resection with mono-segment fusion stratified by the crankshaft phenomenon. (PMC11871682)
• —One-stage posterior excision of lumbosacral hemivertebrae: case series and literature review. (PMC5671867)
• —Surgical and conservative treatment of congenital scoliosis: a search for long-term results. (PMC3120793)
• —Surgical outcomes in children under 10 for congenital scoliosis due to single thoracolumbar hemivertebra, by age at surgery. (PMC8686336)
• —Congenital scoliosis: a narrative review and proposal of a treatment algorithm. (PMC9142820)
• —Current concepts — congenital scoliosis. (PMC5447938)