Posterior Costoplasty (AIS)

Scoliosis is a rotational deformity as well as a sideways curve, and as the spine twists it pushes the ribs on the convex side backwards, creating the rib prominence — the rib hump. This is frequently the most visible feature of scoliosis and, for many young people, their main concern about the appearance of their back. Straightening the spine improves the rib hump but does not always remove it completely, because the rib cage itself has been reshaped by years of rotation. Costoplasty, also called thoracoplasty, directly reshapes the deformed ribs to reduce the prominence and produce a smoother, more symmetrical contour.

When I am performing a posterior spinal fusion, the convex ribs that form the hump are accessible through the same posterior approach. In that situation, when there is a significant rib prominence that needs addressing, I perform the costoplasty posteriorly at the same sitting, resecting segments of the convex ribs to bring down the hump. Doing it together with the fusion means the appearance of the back is addressed as part of the same operation, using the access I already have, rather than needing a separate procedure later. As with the anterior version, it is a considered addition, made when the rib hump warrants it.

Posterior costoplasty involves removing and reshaping short segments of the prominent convex ribs, through the same posterior incision used for the spinal fusion, so that the contour of the back is smoother once the spine has been corrected and fused. It adds to the fusion rather than replacing any part of it. Because it involves the chest wall, the lungs are protected and monitored, and the decision to include it weighs the improvement in the shape of the back against the additional surgery and its effect on breathing in the early recovery.

The evidence shows that posterior convex costoplasty, performed at the same time as a posterior fusion, reliably improves the objective rib hump and improves patients' own ratings of trunk appearance and self-image, beyond spinal correction alone, and that a costoplasty done at the primary operation gives better results than one done later. Short apical rib resection techniques can substantially increase the amount of hump correction compared with conventional methods. The principal consideration is pulmonary: costoplasty causes a temporary early reduction in breathing capacity, but in adolescents this typically recovers toward — or even above — baseline by one to two years, and by mid- to long-term follow-up lung function in those who have a costoplasty is generally no different from fusion alone. Reported complications are mainly chest-related, such as fluid around the lung or a temporary partial lung collapse, so a costoplasty is usually reserved for those with a significant residual rib hump and adequate breathing reserve.

Because the rib cage is involved, breathing is supported and monitored closely in the early days, and a temporary chest drain may sometimes be needed. Some chest-wall discomfort over the reshaped ribs is usual for a period and settles with time and pain relief. Otherwise, recovery follows that of the posterior fusion it accompanies: a hospital stay of several days, a graded return to normal life over the following months, and limitation of strenuous activity while healing. Many young people are pleased with the smoother, flatter contour of the back once the rib hump has been reduced along with the spinal correction. The chest and spine are followed up over the longer term.

• —Barrios C, et al. Costoplasty in adolescent idiopathic scoliosis: objective results in 55 patients. (PMID 8245076)
• —The use of thoracoplasty in the surgical treatment of idiopathic scoliosis. (PMID 17108447)
• —Primary thoracoplasty and pedicle screw instrumentation in thoracic idiopathic scoliosis. (PMC3489258)
• —Short apical rib resection thoracoplasty compared to conventional thoracoplasty in AIS surgery. (PMID 24719039)
• —Posterior spinal fusion with rib resection allows improved deformity correction and patient satisfaction. (PMID 40384585)
• —Pulmonary function after thoracoplasty in the surgical treatment of AIS. (PMID 20625329)
• —Thoracic deformity correction and changes of vital capacity, FEV1 and expiratory flow five years or more after posterior spinal fusion with thoracoplasty. (PMC6698512)
• —Pulmonary function improves in AIS patients who undergo posterior spinal fusion regardless of thoracoplasty: mid-term follow-up. (PMC7870321)
• —What are the effects of posterior corrective surgery, with or without thoracoplasty, on pulmonary function in AIS? Systematic review and meta-analysis. (PMC10240605)
• —Pulmonary function after convex thoracoplasty in AIS treated by posteromedial translation. (PMID 31495473)
• —Concave rib osteotomy: a modified technique revisited. (PMC2078311)
• —Isolated percutaneous thoracoplasty for skeletally mature AIS patients with rib deformity as their only concern. (PMID 23076463)