Shunt Fracture Following Correction of Spinal Deformity

Case Illustrations

Devon Hoover, M.D., Aruna Ganju, M.D., Christopher I. Shaffrey, M.D., Henry Bartkowski, M.D. and Michael J. Rauzzino, M.D.
 
Department of Neurosurgery, Henry Ford Hospital, Detroit, Michigan

KEY WORDS.   myelomeningocele, shunt, scoliosis, surgery–related complication

At birth this 12–year–old boy had undergone an L–3 myelomeningocele and placement of a ventriculoperitoneal shunt for hydrocephalus. The shunt remained functional throughout childhood. By the time he presented to our institution at age 12 years, he had developed progressive neuromuscular scoliosis that was refractory to brace therapy. Preoperatively, his lateral curvature measured 103° with severe pelvic obliquity (Fig. 1 figure left). He underwent placement of posterior instrumentation as well as arthrodesis in which a Luque– Galveston technique was performed by the senior authors (C.S. and H.B.). Postoperatively, his curvature was corrected to 20° (Fig. 1 figure right). Seventy–two hours after surgery, he became increasingly somnolent. A computerized tomography scan revealed acute hydrocephalus (Fig. 2 figure), and he underwent emergency shunt revision. Intraoperatively, the distal tubing in the neck was noted to be calcified and to have fractured, causing a disconnection. The ventricular catheter remained patent, and a distal revision only was performed. His postoperative course was uneventful.

Fig.1 (left & right) Click on image for full view

Fig. 2 Click on image for full view

The incidence of shunt failure after surgical correction of scoliosis in the myelodysplasia population may be as high as 9.1%.3, To our knowledge, a fracture of the shunt in these patients has not been previously described. Fracture of the catheter is related to calcification and tethering, which dispose tubing to fracture when mechanical stresses, such as torso lengthening during deformity correction, are applied.1, 2, In patients with myelodysplasia in whom neurological deterioration occurs after deformity correction, examination for disconnection or fracture of the shunt should be conducted.

 
Acknowledgments:

The authors are indebted to Renee Stacy, R.N., and Kelly Collins, R.N., for their invaluable assistance in the care of this patient and other children from our pediatric spine service.

 
References  
 
1. Boch AL, Hermelin E, Sainte–Rose C: Mechanical dysfunction of ventriculoperitoneal shunts caused by calcification of the silicone rubber catheter. J Neurosurg 88:975–982, 1998.
 
2. Cuka GM, Hellbusch LC: Fractures of the peritoneal catheter of cerebrospinal fluid shunts. Pediatr Neurosurg 22:101–103, 1995.
 
3. Geiger F, Parsch D, Carstens C: Complications of scoliosis surgery in children with myelomeningocele. Eur Spine J 8:22–26, 1999.
 
 
Manuscript received July 30, 1999.
Accepted in final form October 4, 1999.