Spine Deformity With Fused Ribs Treated With Proximal Rib- Versus Spine-Based Growing Constructs

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To compare the use of spine-based versus rib-based implants for the treatment of early-onset scoliosis (EOS) in the setting of rib fusions.

SUMMARY OF BACKGROUND DATA

Treatment for severe early-onset spinal deformity with rib fusions includes growing spine devices with proximal rib or spine anchors. The results of treatment, however, have not been compared between spine-based versus rib-based proximal anchors.

METHODS

169 patients with rib fusions treated with rib-based or spine-based constructs and minimum two-year follow-up were included. Sixteen patients were treated with proximal spine-based anchors and 153 with proximal rib-based devices (VEPTRs). Overall, 104 of the patients with rib-based fixation underwent thoracoplasty at the index surgery. We evaluated change in T1-T12 and T1-S1 height, coronal Cobb angle, kyphosis, and number of lengthening/revision surgeries.

RESULTS

Kyphosis increased a mean of 7° in the rib-based group and decreased a mean of 20 degrees in the spine-based group (p = .002). Major Cobb angle decreased in both groups (p < .0001); however, the spine-based group had greater Cobb angle improvement (24 vs. 11 degrees, p = .04). From implant and lengthening of distraction devices, there was a mean 3.3-cm (22%) increase in T1-T12 height and a mean of 8.0 lengthenings in the rib-based group compared with a 5.7-cm increase and 6.3 lengthening surgeries in the spine-based group. Patients with rib-based constructs had a mean of 11 total procedures, whereas spine-based patients had a mean of 8.

CONCLUSIONS

Patients underwent a mean of eight lengthening surgeries before final fusion or cessation of lengthening with a modest 2.3-cm increase in T1-T12 height. Compared with proximal rib anchors, proximal spine anchors controlled kyphosis and improved Cobb angle correction for early-onset scoliosis with rib fusions.

Nutritional improvement following growing rod surgery in children with early onset scoliosis

PURPOSE

We aimed to evaluate the nutritional status of children with early onset scoliosis (EOS) and to determine if treatment with growing rod instrumentation improves weight percentile.

METHODS

Data was retrospectively collected on 88 EOS patients treated with growing rods at six institutions. Mean age at surgery was 5.8 years, and mean Cobb angle was 75°. All patients were followed for at least 2 years (mean 4 years). Weights were converted to normative percentiles based on the patients' age and gender.

RESULTS

Preoperatively, 47 % (41/88) of patients were <5 percentile for weight, thus failing to thrive. There was a significant increase in mean postoperative weight percentiles at latest follow-up (p = 0.004). 49 % of patients gained weight, with a mean of 18 percentile. A significant relationship exists between age at initial surgery and percentile weight gain (p < 0.005), with children <4 years old not demonstrating postoperative improvement. This relationship was not confounded by preoperative weight, preoperative Cobb angle, or years of follow-up (p > 0.05). Children with neuromuscular and syndromic diagnoses do not appear to improve their mean nutritional status after surgery when compared to patients with idiopathic or congenital/structural scoliosis (p = 0.006).

CONCLUSION

Following growing rod treatment, there was significant improvement in nutritional status in approximately 50 % of patients, similar to that reported with VEPTR. Neuromuscular and syndromic patients did not experience nutritional improvement post-operatively. These findings support the theory that growing rods improve the clinical status of EOS patients, as nutritional improvement is one outcome of improved clinical status. The relationship between age at initial surgery and nutritional improvement is intriguing.