Temperatures within the lumbar disc and endplates during intradiscal electrothermal therapy: formulation of a predictive temperature map in relation to distance from the catheter.
METHODS
Temperatures were measured in human cadaveric lumbar discs during intradiscal electrothermal therapy.


OBJECTIVE
To determine if sufficient temperatures for collagen denaturation and nociceptive ablation can be achieved at clinically significant distances from the intradiscal electrothermal therapy heating catheter.


BACKGROUND
Previous cadaveric studies have contested the ability of the intradiscal electrothermal therapy catheter to produce sufficient temperatures to denature collagen and cause neural ablation within the posterior anulus of the disc. However, these experiments used clinically unrepresentative device placements along the anterolateral anulus.


METHODS
Intradiscal electrothermal therapy was performed in 14 human cadaveric discs. Devices were inserted using a standard posterolateral approach to orient the heating catheter along the posterior anulus. Temperature recordings were collected using multiple sensors placed along the posterior anulus, anterior anulus, and endplates.


RESULTS
Temperatures greater than 60 C and 65 C were achieved in 14 and 5 specimens, respectively, at distances up to 2 mm from the catheter. Between 2 and 4 mm, more than 60 C was achieved in all specimens. More than 45 C was achieved in all specimens at distances of 9 to 14 mm from the device.


CONCLUSIONS
Temperatures sufficient for collagen denaturation and nociceptive ablation were detected at distances greater than previously documented. These data suggest that intradiscal electrothermal therapy's proposed heat-dependent mechanisms of action are achievable in most discs. Among other factors, interspecimen variability of maximum temperatures may help explain the somewhat inconsistent clinical results following intradiscal electrothermal therapy.
Bono
Christopher M
CM
Department of Orthopaedic Surgery, Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts 02118-2393, USA. bonocm@prodigy.net
Iki
Kobi
K
Jalota
Anjali
A
Dawson
Kathryn
K
Garfin
Steven R
SR
D000328:Adult; D000368:Aged; D000818:Animals; D002102:Cadaver; D017115:Catheter Ablation / Q000009:adverse effects; D002404:Catheterization; D002417:Cattle; D003094:Collagen / Q000737:chemistry; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000502:physiology / Q000601:surgery*; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000209:etiology / Q000628:therapy; D011489:Protein Denaturation; D013696:Temperature; D013814:Thermal Conductivity
D003094:Collagen