Patients treated for AIS showed persistent cervical malalignment signs at 30-year follow-up

ORLANDO, Fla. — A 30-year follow-up showed patients treated for adolescent idiopathic scoliosis between 1975 and 1992 frequently had cervical kyphosis in adulthood and nearly 60% of them had radiographic evidence of cervical spine arthritis.

“We found there was a high prevalence of cervical kyphosis in our population with adolescent idiopathic scoliosis,” Ernest Young, MD, said at the American Academy of Orthopaedic Surgeons Annual Meeting.

Young, A. Noelle Larson, MD, and colleagues conducted their study to examine the outcomes of pediatric patients treated for adolescent idiopathic scoliosis (AIS) who had a minimum 20-years follow-up. Investigators also sought to identify arthritis as defined by the Kellgren-Lawrence scale or any alterations in thoracic sagittal alignment.

AIS presents with cervical kyphosis

Initial AIS treatment was operative in 21 patients and nonoperative in 12 patients. Patients needed to have high quality anteroposterior and lateral full-spine radiographs in childhood and at final follow-up to be included in this study.

Larson noted in an interview with Spine Surgery Today that patients with AIS also typically presented with cervical kyphosis.

“Patients with AIS frequently had cervical kyphosis, up to 50% of the time, compared to 9% reported in literature controls, and also frequently had cervical arthritis,” Larson told Spine Surgery Today.

In addition, loss of thoracic kyphosis in childhood is associated with neck arthritis in adulthood, she said.

Markers for cervical disease

Young and colleagues looked at certain markers for cervical disease as defined in the literature and also rated patients’ alignment based on the parameters of cervical spine alignment, such as the extent of kyphosis or lordosis.

“There was no correlation between the cervical alignment and the eventual patient-reported outcomes for arthritis or surgery at follow-up,” Young said.

The investigators reported the mean Scoliosis Research Society (SRS), Spinal Appearance Questionnaire, Oswestry Disability Index (ODI) and EuroQual-5D scores did not differ significantly in patients who had adult cervical spine malalignment.

In terms of cervical alignment results at follow-up, “Most of our patients were kyphotic by definition of 10°, and those rates were about the same between the operative and nonoperative groups,” Young said.

Furthermore, most of the patients had normal kyphosis in the thoracic spine at follow-up, he noted.

Majority have cervical arthritis

“Nearly 60% of our patients had moderate to severe cervical arthritis at follow-up,” however, there were no differences in arthritis rates between the operative and nonoperative patients, Young said.

In addition, thoracic hypokyphosis at final follow-up was associated with worse SRS-22 and ODI scores.

In both the nonoperative and operative AIS treatment groups, cervical spine malalignment persisted into adulthood with high rates of radiographic cervical spondylosis at follow-up. Also, results of the study showed patients tended to have a higher rate of cervical fusion and severity of cervical arthritis compared to the normal population.

The study data showed lower patient-reported outcomes in adults with thoracic hypokyphosis. Thus, the long-term follow-up data suggest correction of childhood thoracic hypokyphosis should be a surgical goal when treating AIS, Larson said. – by Susan M. Rapp and Robert Linnehan

Reference:
Young E, et al. Paper #91. Presented at: American Academy of Orthopaedic Surgeons Annual Meeting; March 1-5, 2016; Orlando, Fla.

For more information:

A. Noelle Larson, MD, can be reached at Mayo Clinic, 200 1st St. SW, Rochester, MN; email: larson.noelle@mayo.edu.
Ernest Y. Young, MD, can be reached at Mayo Clinic, 200 1st St. SW, Rochester, MN; email: young.ernest@mayo.edu.

Disclosures: Larson and Young report no relevant financial disclosures. The study was funded by a Directed Research Grant from the Scoliosis Research Society.