Historical controlled trial.
To clarify the usefulness of cryotherapy after spine surgery.
Cryotherapy has generally been performed subsequent to surgery on joints and in this application its clinical effects are well understood. However, cryotherapy has yet to be used following spine surgery. Its clinical efficacy in this context is unknown.
Thirty six patients had undergone one level microendoscopic surgery. Sixteen were enrolled into the cooling group, with the remaining 20 making up the no postoperative cryotherapy control group. Cryotherapy was performed at 5℃ using an icing system. A silicone balloon catheter with a thermo sensor on the tip was placed in the surgical wound. The temperature in the wound was recorded every 30 minutes until the next morning. The relationship between the depth of the sensor and the temperature in the wound were investigated using simple linear regression analysis. Laboratory data, visual analogue scale (VAS) for wound pain and postoperative bleeding were investigated.
The mean temperature in the surgical wound was 37.0 in the control group and 35.0℃ in the cooling group (
The temperature in the wound was decreased significantly by spinal surgery cryotherapy.
Cryotherapy has generally been performed subsequent to joint surgery. Tissue metabolism is suppressed because the temperature of tissues decreases, which lessens pain, edema and postoperative bleeding, and promotes rapid recovery of range of motion after surgery [
The current study examined subjects following spinal surgery cryotherapy to assess whether the temperature of the deep tissues in the surgical wound decreases, whether clinical benefits including reduction of inflammation, pain and postoperative bleeding are obtained and complications or unpleasant conditions, such as limitation in postural movement.
From January 2008 to April 2009, 37 consecutive patients (24 males and 13 females) who had undergone one level microendoscopic decompression for lumbar spinal stenosis or one level microendoscopic discectomy for lumbar disc herniation were included in this study. All procedures were performed at our institution by a single surgeon who was experienced in microendoscopic spinal surgery. Exclusion criteria included patient refusal of cryotherapy, two or more levels of microendoscopic decompression or discectomy and multiple operations on the back. One patient was excluded due to conversion to open surgery. No patient refused cryotherapy and none had undergone multiple operations on the back. All subjects who received cryotherapy consented to participate.
Postoperative cryotherapy was performed in 16 consecutive patients (10 males and 6 females) between September 2008 and April 2009 (cooling group), and postoperative cryotherapy was not performed for 20 consecutive patients (13 males and 7 females) between January 2008 and August 2008 (control group) (
Cryotherapy was performed by using an Icing System CF3000 (Japan Sigmax, Tokyo, Japan). After surgery, a cooling pad (288 mm×330 mm) was applied to the wound site over a light dressing and clothes, and secured with a bust band (
A 4.0 mm-diameter silicone balloon catheter with a thermo sensor on the tip (Terumo, Tokyo, Japan) was placed in the surgical wound and used for suction drainage. The temperature in the wound was automatically recorded repeatedly every 30 minutes until the next morning by using a Coretemp CM-210 (Terumo). In the cooling group, the depth of the thermo sensor was measured on the lateral view of a postoperative plain roentgenogram. Relationships between the depth of the thermo sensor and the temperature in the wound were investigated using simple linear regression analysis.
Laboratory data of creatine phosphokinase (CPK) (preoperation, postoperative day 1) and C-reactive protein (CRP) (postoperative day 3), visual analogue scale (VAS) assessing wound pain (postoperative day 1 and 7) and the amount of postoperative bleeding until the next morning were recorded. We performed statistical analyses between the two groups using the Mann-Whitney U-test and the Fisher exact probability test were used, with
Complications and unpleasantness during cryotherapy were also investigated. Our institutional review board approved this study.
In the control group, the temperature in the surgical wound gradually increased after surgery, reaching a thermostatic phase several hours after surgery. In the cooling group, the temperature in the surgical wound gradually decreased after surgery, reaching a thermostatic phase a few hours after surgery (
CPK, CRP, VAS, and the amount of postoperative bleeding were not significantly different between the groups (
This is the first report of the measurement of temperature of the deep tissue of the body trunk directly during cryotherapy. Cryotherapy has generally been performed with an ice bag. However, it has been difficult to cool the body trunk, especially the spine in the supine or lateral position, which is why ice bag cryotherapy has not been employed after spinal surgery.
The icing system CF3000 is a device that can establish a liquid temperature from 0℃ to 13℃ by the Peltier effect, circulating the liquid to the pad and cooling the wound once the pad is attached. In this study, use of the icing system CF3000 enabled cryotherapy in the supine or lateral position following spinal surgery. None of the patients complained of unpleasantness or sensory disturbance, and there were no complications including infection or delayed healing of the surgical wound.
There have been only a few reports concerning cryotherapy with a cooling pad post spinal surgery. Reduced postoperative pain and decreased length of hospital stay have been reported [
Presently, the temperature in the wound in the cooling group was decreased to a statistically significant degree compared with the control group. However, the difference was small (2.0℃) and there were no clinical benefits, such as reduction of inflammation, pain, or postoperative bleeding. In addition, the regression line between the depth of the thermo sensor and the temperature in the wound demonstrated that the cooling effect to the deep tissues of the body trunk was very small.
Warren et al. [
There are some potential limitations of this study. First, this study was not a randomized trial. However, since all procedures were performed by a single surgeon with experience in microendoscopic surgery, and because in our institutions spinal microendoscopic surgery has been performed on more than 100 patients, it is likely that there was no difference in surgical technique and postoperative therapy among the subjects. Second, the subjects were treated using less invasive microendoscopic procedures. The effects of cryotherapy in patients who undergo more invasive spinal surgery, such as spinal fusion, need to be determined. Finally, we were not able to find significant differences between the groups in the laboratory data or the amount of postoperative bleeding, possibly due to the small sample size. Power analysis using G*Power 3.1 software (freely available on the Internet) showed that approximately 58 patients in the cooling group and 72 patients in the control group would be necessary to obtain sufficient power, around 0.8, an effect size of 0.5, and an a error probability of 0.05. Consequently, the results of previous studies [
We performed cryotherapy after one level microendoscopic lumbar spine surgery using the Icing System CF3000. This is the first report measuring temperature of the deep tissue of the body trunk directly during cryotherapy. Although no significant differences between the groups in the laboratory data and the amount of postoperative bleeding were observed, wound temperature decreased significantly after spinal surgery cryotherapy.
No potential conflict of interest relevant to this article was reported.
Use of the cooling pad. The cooling pad (288 mm×330 mm)
Transition of the wound temperature.
The temperature of the shallow tissues in the surgical wound was lower, but the temperature of the deep tissues was higher.
Demographic data
Values are presented as average±standard deviation.
a)Mann-Whitney U-test; b)Fisher exact probability test.
Comparison of measurement value
Values are presented as average±standard deviation.
CPK, creatine phosphokinase; POD, postoperative day; CRP, C-reactive protein; VAS, visual analogue scale.