SpineUniverse Case Study Library

Progressive 90-degree Scoliosis

This case study is brought to you by:
What is this?

Patient History

The patient is a 12-year-old female, premenarcheal, who stands 4'-5" and weighs 61 pounds. She presents with a rapidly progressive large scoliosis; 38-degrees at age 10 and 88-degrees at age 12.


She has significant cardiopulmonary disease with admissions for heart failure and is treated with Digoxin, Lasix®, and Vasotec®. The patient has demonstrated restrictive pattern on pulmonary tests.

Prior Treatment

Previously, the patient underwent cardiac surgery.


The patient's 90-degree curve (Figure 2) is extremely stiff, bending only to 76-degrees. A CT scan revealed extremely small and dysmorphic pedicles on the concavity of the main curve.

anterior posterior x-ray, progressive scoliosis
Figure 1

90-degree progressive scoliosis
Figure 2

anterior posterior x-ray, progressive scoliosis
Figure 3

lateral x-ray, progressive scoliosis
Figure 4

90-degree progressive scoliosis

40-degrees C6-T3 (22)




90-degrees T4-L2 (76)





45-degrees L2-L5 (35)




lateral x-ray, progressive scoliosis


Large progressive thoracic / lumbar scoliosis with concomitant cardiopulmonary disease.

Suggest Treatment

Indicate how you would treat this patient by completing the following brief survey. Your response will be added to our survey results below.

Selected Treatment

A preoperative CT scan revealed extremely small and dysmorphic pedicles on the concavity of the main curve. Therefore, pedicle screw fixation at this apex would present a significant challenge.

The patient's cardiac team indicated the need for future cardiac MRI studies, which guided my choice of a titanium system. Since the patient weighs only 61 pounds, I determined a 5.5 system would be an appropriate profile choice, although there was concern about correcting a large stiff curve with such a system.

Clearly, osteotomies are necessary at the curve apex. Given her cardiac disease, asymmetrical pedicle subtraction was not an ideal choice. Multiple Smith Peterson osteotomies (SPO) were planned at the apex. Universal Clamps® were passed during the osteotomies and tightened after standard application of the first rod.

Difficult apical pedicles suggested the need for additional segmental fixation at the apex. Multiple apical SPOs make the passage of sublaminar fixation convenient. Zimmer Spine's Universal Clamp® was a natural choice given the clinical considerations.

The operative time was about 5.5 hours. Estimated blood loss was about 750 cc; Cell Saver® and antifrinolytics were used.

The patient's surgery was uneventful with a smooth recovery.


Financial Disclosure
Michael Vitale, MD, MPH served as a consultant and clinical educator to Abbott Spine (now Zimmer Spine).



Postoperatively, she is 30-degrees at T4-L2 on standing AP with good balance in both planes.

postoperative anterior posterior x-ray
Figure 5

postoperative anterior posterior x-ray
Figure 6

Case Discussion

This is a very nice case to highlight the major change in spinal deformity surgical treatment over the last 10 years. In the 1990's, this 12-year-old patient with a 90-degree stiff (side-bending to only 76-degrees) scoliosis, who is skeletally immature, (premenarcheal) would invariably have been recommended to have an anterior (either via open thoracotomy or endoscopic approach) release and spinal fusion along with a concomitant posterior instrumentation and fusion. Given her precarious cardiac and pulmonary status, this would have been a very challenging medical, as well as surgical undertaking. Perhaps consideration, for several weeks, of prolonged halo traction to avoid an anterior procedure would have been advisable. However, currently, many centers across North America and the world have been treating these types of patients with a single stage posterior segmental spinal instrumentation and fusion as was elegantly done here.

The two main keys to this approach are the posterior release performed, here via multilevel, periapical facet and ligament releases (Smith Petersen Osteotomies (SPOs) or Ponte osteotomies), and segmental pedicle screw fixation. In numerous studies, this approach has been shown to obviate a preliminary anterior release and fusion for large and stiff idiopathic scoliosis (Luhmann et al Spine 2005, Arlet et al Euro Spine J 2004).

The approach utilized in this case takes advantage of the posterior release by placement of a type of sublaminar cable / clamp device utilized on the apical concavity, thus avoiding the potential dangers of apical concave pedicle screw placement. This is a very nice alternative to the use of apical concave pedicle screws and, along with the use of multilevel screws cephalad and caudad in the construct, has led to an excellent correction of the frontal plane deformity.

We have found that placement of apical concave pedicle screws in all types of pediatric and adult scoliosis is feasible, especially with a preliminary posterior ligament and facet release, which allows access to the spinal canal with palpation of the medial concave aspect of the pedicle. Thus, screws can be placed with greater safety in this region.

One issue that is not resolved is the long-term risk of crankshaft in an immature patient, such as the one presented. Although her triradiate cartilages appear fully ossified on the radiographs, she may still be at some risk of crankshaft due to her premenarcheal, Risser 0 status. Thus, theoretically, three-column purchase of the apical vertebrae by pedicle screws would lessen that risk, and if apical concave Universal Clamps are chosen for fixation there, convex sided pedicle screws can still be placed for a three-column purchase of the convex pedicle / body.

Overall, this was an excellent approach for this very challenging small and unhealthy girl with cardiac and pulmonary disease, along with a very large and stiff scoliotic deformity. By obviating an anterior procedure, the short- and long-term complications of a circumferential approach were avoided, which has been shown in numerous studies to have a significantly greater postoperative complication rate versus single-stage posterior procedures for various pediatric and adult deformities (Lee et al, Spine 2006, Dobbs et al, Spine 2006, Carreon et al Journal of Bone and Joint Surgery 2007, and Kuklo et al Spine 2007). The operative time and blood loss, two factors that consistently negatively correlate with postoperative complications, were also quite commendable. I congratulate the authors on this excellent approach to this problem.


Get new patient cases delivered to your inbox

Sign up for our healthcare professional eNewsletter, SpineMonitor.
Sign Up!