The Treatment of Kyphotic Deformity Using Kyphoplasty for Vertebral Compression Fractures

S. Dudeney, MD1,
I. Lieberman, MD1,
F. Phillips, MD2,
MaryKay Reinhardt, RN1,
Gordon Bell, MD1
* (a – Kyphon Incorporated)
1Cleveland Clinic Cleveland, OH,
2University of Chicago, Chicago, IL

PURPOSE:
To evaluate the early experience with inflatable balloon tamp reduction and cement augmentation, "Kyphoplasty", in the treatment of kyphotic deformity secondary to osteoporotic vertebral compression fractures.

BACKGROUND:
Kyphoplasty involves the penetration of the vertebral body with a cannula, followed by insertion of an inflatable balloon tamp. The balloon tamp restores the vertebral body back towards its original height, while creating a cavity to be filled with PMMA bone cement. The cement injection is done under relatively low pressure in an attempt to reduce the risk of extravasation. Cement augmentation of the vertebral body, “Vertebroplasty”, has been used to treat painful osteoporotic fractures in the past. Vertebroplasty makes no attempt to restore height and correct the kyphotic deformity which results from an osteoporotic compression fracture. Kyphotic deformity propagates further compression fractures in these patients by altering spinal biomechanics.

PATIENTS & METHODS:
Sixty–four consecutive kyphoplasty procedures were performed in 29 patients. The commonest indication was painful primary or secondary osteoporotic vertebral compression fractures (24 patients). Five patients presented with painful compression fractures due to multiple myeloma. Mean duration of symptoms was 3.5 months. Symptomatic levels were identified by correlating the clinical data with MRI findings. Pre–operative and post–operative x–rays were compared to calculate the percentage height restored. Outcome data was obtained by comparing preoperative and latest postoperative SF–36 data.

RESULTS:
There were no major complications related directly to use of this technique. Leakage rates were low, occurring in 5 levels (8%). The mean percentage height restored by the procedure was 38%. SF36 bodily pain scores improved from 13.6 to 47.2 (p=0.004). Physical function improved from 28.7 to 55.3 (p=0.02).

CONCLUSIONS:
Kyphoplasty is associated with early improvement of pain and function as well as restoration of vertebral body height.

* If noted, the author indicates something of value received. The codes are identified as: a research or institutional support, b–miscellaneous funding, c–royalties, d–stock options, e–consultant.