Study Outcome
In an initial Phase I Cleveland Clinic Institutional Review Board-approved study,
published in Spine, (Lieberman et al, Spine Vol 26 No 14 July 2001), 70 consecutive
kyphoplasty procedures were performed in 30 patients over 38 sessions. Of these
patients, 24 had painful primary (n=19) or secondary (n=5) osteoporotic vertebral
compression fractures unresponsive to nonoperative modalities. Six patients
presented with painful compression fractures due to multiple myeloma. The average
duration of symptoms was 5.9 months (range 0.5 - 24). Symptomatic levels were
identified by correlating the clinical data with magnetic resonance imaging
findings of marrow signal changes consistent with compression fractures. The
levels treated ranged from T6 to L5, with the majority at the thoracolumbar
junction.
Outcome data were obtained by comparing preoperative and latest postoperative
SF-36 data. All 30 patients tolerated the procedure well and improvement in
pain and mobility was seen early. Virtually all patients subjectively reported
immediate relief of their typical fracture pain, and no patient complained of
worse pain at the treated levels. Radiological height measurement of all 70
levels treated (regardless of fracture age) demonstrated that in 70% of the
vertebral bodies, kyphoplasty restored on average 47% of the lost height. Cement
extravasation into the perivertebral veins was noted in only six vertebral bodies
(8%) in the early cases, and they were all clinically insignificant. SF-36 scores
for bodily pain, physical function, role physical, vitality and mental health
all showed statistically significant improvement either reaching or approaching
the age-matched SF-36 historical controls. At final follow-up, no major complications
related directly to use of this technique or the inflatable bone tamp were reported.
Since August 1998, orthopaedic surgeons here have treated more than 100 patients
and 250 vertebral bodies. Results of the initial series have been maintained
in the most recent follow-up of over 70 consecutive patients out to 14 months.
It appears, like hip fracture surgery, that kyphoplasty will be most successful
with early intervention.
Vertebral Body Compression Fractures Adversely Impact Overall Health
An estimated 700,000 pathological vertebral body compression fractures occur
in the United States each year. Of these, more than one-third become chronically
painful. The majority of these fractures (about 85%) are the result of primary
osteoporosis; the remainder are due to secondary osteoporosis or osteolytic
spinal metastases. These compression fractures lead to progressive deformity
and changes in spinal biomechanics and are believed to contribute to increased
risk of further fracture.
Whether the fracture is painful or not, the spinal deformity caused by two
or more fractures dramatically impacts health, daily living and medical costs
through loss of lung capacity, reduced mobility, chronic pain, loss of appetite
and/or clinical depression. With each osteoporotic vertebral compression fracture,
a 9% loss in predicted forced vital capacity and a 15% age-adjusted increase
in mortality can be expected.
Traditionally, vertebral body compression fractures were treated medically
and rarely with surgical modalities. Unfortunately, the medical management of
painful fractures (bed rest, hospitalization, narcotic analgesics and bracing)
does nothing to restore spinal alignment and compounds problems associated with
osteoporosis. Due to the poor quality of osteoporotic bone and the inherent
risks and invasive nature of surgical treatment of vertebral body compression
fractures, the procedure has been limited to cases in which there is concurrent
spinal instability or neurologic deficit.
