SPINE Volume 40, Number 15, pp E859-E865 ©2015, Wolters Kluwer Health, Inc. All rights reserved.
RANDOMIZED TRIAL
Epidural Steroids After a Percutaneous Endoscopic Lumbar Discectomy Sang-Ha Shin, MD,* Byeong-Wook Hwang, MD, PhD,† Han-Joong Keum, MD,* Sang-Jin Lee, MD, PhD,† Sang-Joon Park, MD,† and Sang-Ho Lee, MD, PhD*
Study Design. Randomized controlled study from a single surgeon. Objective. The objective of the present study is to assess the effectiveness of the administration of epidural steroids in patients who undergo a percutaneous endoscopic lumbar discectomy (PELD) because of a herniated lumbar disc. Summary of Background Data. Steroids are drugs that show strong anti-inflammatory effects; in specific, the effects of epidural steroid application after an open lumbar discectomy have been studied extensively. However, no study has been conducted on the effects of perioperative epidural steroids after PELD. Methods. One hundred patients who had undergone a PELD because of a herniated lumbar disc were randomized into 2 groups. Patients in group 1 were subjected to an epidural steroid application after a PELD, whereas patients in group 2 were treated with saline after a PELD. Results. There was a significant decrease in visual analogue scale (VAS) scores (back, leg) and Oswestry Disability Index at all examinations (P < 0.01). When comparing the 2 groups, group 1 showed lower levels of VAS scores (back) in all examinations than group 2 but was not statistically significant (P = 0.257). In VAS score (leg), group 1 showed a significant decrease compared with the group 2 at 1 and 4 weeks of follow-up examination (P = 0.020, P = 0.032). In Oswestry Disability Index, group 1 showed a significant decrease compared with the group 2 at 1-week follow-up examination (P < 0.01). The mean hospital stay was statistically significantly shorter in group 1 (P < 0.01). The mean periods before returning to work for those who returned to work in group 1 and group 2 were 4.45 ±
From the *Department of Neurosurgery, Wooridul Spine Hospital, Seoul, Korea; and †Department of Neurosurgery, Busan Wooridul Spine Hospital, Busan, Korea. Acknowledgment date: November 5, 2013. First revision date: April 16, 2014. Second revision date: June 17, 2014. Acceptance date: July 29, 2014. The manuscript submitted does not contain information about medical device(s)/drug(s). Wooridul Spine Foundation grant funds were received to support this work. No relevant financial activities outside the submitted work. Address correspondence and reprint requests to Sang-Ha Shin, MD, Department of Neurosurgery, Wooridul Spine Hospital, 445, Hakdong-ro, Gangnam-gu, Seoul, 135-951, South Korea; E-mail: [email protected] DOI: 10.1097/BRS.0000000000000990 Spine
3.59 weeks and 6.48 ± 4.88 weeks, respectively, when measured at follow-up at 6 months; the period in group 1 was statistically significantly shorter (P = 0.024). Conclusion. Epidural steroids after a PELD reduce back pain and leg pain while improving functional outcomes in the short-term postsurgery period. Key words: steroids, endoscopic discectomy, lumbar disc herniation, clinical results. Level of Evidence: 2 Spine 2015;40:E859–E865
T
he back pain and leg pain that accompany lumbar disc herniation are known to generally occur because of physical pressure on the nerves of the herniated nucleus pulposus and inflammatory reactions.1 Patients experiencing herniated nucleus pulposus are surgically treated when they do not respond to conservative treatment. Although the removal of herniated discs through surgery removes physical pressure on the nerves, the inflammatory reactions remain even after surgery, and the perineural fibrosis that progresses after surgery can induce persistent pain and physical disabilities.2 Therefore, many studies have been conducted with a goal of finding a method to relieve pain by reducing inflammatory reactions and late peridural scar formation through the application of epidural steroids after an open lumbar discectomy.3–11 Although somewhat controversial, many studies have reported on perioperative epidural steroids as a method to relieve pain in the short-term postoperative period. After Kambin and Gellman12 reported on minimal access surgery in lumbar disc herniation in 1983, endoscopic discectomy has rapidly gained worldwide popularity because of the development of endoscopic devices and an increased need by patients. This procedure is widely performed by interventional pain physicians as well as by spine surgeons because it requires no general anesthesia or admission to a hospital. However, no study has yet focused on the effects of perioperative epidural steroids after an endoscopic discectomy. Thus, the authors performed perioperative epidural steroid application after percutaneous endoscopic lumbar discectomy (PELD) and tried to examine the effects and characteristics of the application. www.spinejournal.com
E859
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E859
03/07/15 10:04 AM
RANDOMIZED TRIAL MATERIALS AND METHODS Subjects This study was approved by our institutional review board. All procedures were performed by a single surgeon and informed consent was obtained from each patient. One hundred twenty-six eligible patients diagnosed at our institution with herniated discs during a period from October 2010 to March 2012 were assessed.
Inclusion Criteria Patients in the following cases were included in the present study: if the patient's symptom duration was at least 6 weeks and conservative treatment failed, if the patient had soft disc and contained disc herniation limited to a level that was located at the paracentral or central portion, or if the patient had low-grade extruded disc herniation, or more specifically, the degree of craniocaudal migration was smaller than the height of posterior marginal disc space measured in the magnetic resonance imaging (MRI) sagittal plane. Patients in the following cases were excluded from the present study: if the patient showed profound motor weakness, including foot drop, calcified, sequestrated, or recurrent disc herniation; if an endoscopic foraminoplasty was considered because of bony obstacles; disc herniation was accompanied by spinal stenosis or spinal instability; spondylolisthesis; or disc herniation accompanied by diabetes mellitus. Patients who were immunocompromised, under anticoagulant therapy, diagnosed with an uncontrolled acute or
Steroids After Endoscopic Discectomy • Shin et al
chronic medical illness, or in a pregnant or lactating state were also excluded. Twenty-two patients who did not meet the inclusion criteria and 4 patients who refused to participate in the study were excluded, and thus 100 patients were registered. During the registration period, patients’ age, sex, symptom duration, medical/surgical history, visual analogue scale (VAS) scores of leg and back, and previous history of epidural injections were examined; radiological, physical, and neurological examinations were also conducted. The 100 registered patients were randomly assigned to group 1 (n = 50) or group 2 (n = 50). Block randomization was done using a computerized sequence generator. The operator and the patient were blinded from group assignment. One patient in group 1 who showed uncontrolled bleeding while a PELD was performed and 1 patient in group 2 who showed persistent pain due to insufficient decompression were converted into open surgery and thus were excluded from analyses. Group 1 patients were subjected to epidural steroid application after a PELD and group 2 patients were subjected to a saline application after a PELD. VAS scores of leg and back and Oswestry Disability Index (ODI) were examined in the patients in the 2 groups at follow-up at 1 week, 4 weeks, and 26 weeks postsurgery. One patient in group 2 who underwent an open discectomy because of recurrent disc herniation was excluded from analyses. Thus, 49 patients in group 1 and 48 patients in group 2 were examined. In addition, postoperative hospital stays and returns to work were examined in all patients (Figure 1). Clinical results from follow-up were
Figure 1. Flowchart of the patient. PELD indicates percutaneous endoscopic lumbar discectomy.
E860
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August 2015
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E860
03/07/15 10:04 AM
RANDOMIZED TRIAL
Steroids After Endoscopic Discectomy • Shin et al
was encouraged for 6 weeks after the procedure. Patients were advised to refrain from sexual activities and daily ambulation of greater than 4 km for at least 2 weeks, and sitting on the floor for any amount of time or on a chair for more than 1 hour was forbidden.
Statistical Analysis Clinical results were statistically analyzed using the SPSS Win 14.0 program. Data were analyzed into arithmetic means and standard deviations, and repeated measures analysis of variance and t tests were used for statistical analyses. Repeated measures analysis of variance was used to test the differences between both groups in VAS scores (leg and back) and ODI. T tests were used to test the differences between both groups in outcomes of hospital stay and returning to work. Results were considered statistically significant if the P value was less than 0.05.
RESULTS Figure 2. Fluoroscopic view. The radiocontrast agent is filled into the S1 root and into the thecal sac from the decompressed disc space.
blinded from the patient and the operator and were collected and analyzed by a separate researcher.
Surgical Technique and Epidural Steroid Application The conventional transforaminal endoscopic discectomy technique was implemented through the foraminal window in all patients.13,14 After sufficient decompression and identification of epidural pulsation, a radiocontrast agent was injected through the obturator cannulation using a syringe and the epidural filling pattern was checked (Figure 2). Thereafter, a solution made by mixing 1 mLof triamcinolone (40 mg) with 4 mL of saline was administered to each patient in group 1, and 5 mL of saline was administered to each patient in group 2 (Figure 3). The patients were taken out of the operating room after subcutaneous sutures and dressing. A postoperative MRI was conducted on the day of surgery in all patients. The patients were permitted to go home when there was no bleeding on MRI, successful decompression was shown, and the patients’ pain was tolerable. One gram of ceftezole was injected as a prophylactic antibiotic in all patients 1 hour prior to the procedure. Application of a spinal-supporting corset
Of the 50 patients assigned to group 1, 21 were male and 29 were female, and the patients’ average age was 34.52 (range: 19–57) years. Their mean symptom duration was 22.36 (range: 6–104) days and their involved levels were L3–L4, L4–L5, and L5–S1 in 4, 35, and 11 patients, respectively. Thirty-seven patients had a history of epidural steroid injection. Of the 50 patients assigned to group 2, 19 were male and 31 were female, and the patients’ average age was 35.84 (range: 18–61) years. Their mean symptom duration was 20.04 (range: 6–78) days and their involved levels were L3–L4, L4–L5, and L5–S1 in 5, 36, and 9 patients. Thirtytwo patients had a history of epidural steroid injection. The demographic data of the 2 randomized groups were not statistically significantly different (Table 1). Except for 1 patient in group 1 who showed uncontrolled bleeding during an endoscopic discectomy and 1 patient in group 2 who showed persistent pain due to insufficient decompression, successful decompression was identified through postoperative MRI in all of the patients. There was a significant decrease in VAS scores (back and leg) and ODI at all examinations (P < 0.01). When comparing the 2 groups, group 1 showed lower levels of VAS scores (back) in all examinations than those in group 2 but was not statistically significant (P = 0.257) (Figure 4A). In VAS scores (leg), group 1 showed a significant decrease compared with
Figure 3. Epidural steroid application. Epidural steroids can be easily injected through obturator cannulation using a syringe. Spine
www.spinejournal.com
E861
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E861
03/07/15 10:04 AM
RANDOMIZED TRIAL
Steroids After Endoscopic Discectomy • Shin et al
TABLE 1. Patient Demographics P
Group 1
Group 2
50
50
21/29
19/31
0.687
Mean age (yr)
34.52 (19–57)
35.84 (18–61)
0.530
Mean symptom duration (wk)
22.36 (6–104)
20.04 (6–78)
0.496
L3–L4
4
5
L4–L5
35
36
L5–S1
11
9
37
32
No. patients Sex (male/female)
Involved level
Previous history of epidural steroid injection
group 2 at 1 and 4 weeks of follow-up examination (P = 0.020, P = 0.032), but this association was not statistically significant at 26 weeks of follow-up (P = 0.347) (Figure 4B). In ODI, group 1 showed a significant decrease compared with the group 2 at 1-week follow-up examination (P < 0.01), but this association was not statistically significant at 4 and 26 weeks of follow-up (P = 0.223, P = 0.641) (Figure 5).
0.284
The mean hospital stays were 1.49 ± 0.68 days in group 1 and 2.14 ± 0.89 in group 2, respectively, and the value in group 1 was statistically significantly shorter (P < 0.01). At the 6-month follow-up period, 47 patients returned to work in group 1 and 46 in group 2, and their mean periods of returns to work were 4.45 ± 3.59 and 6.48 ± 4.88 in group 1 and group 2, respectively, and the value in group 1 was statistically significantly shorter (P = 0.024) (Figure 6). During the follow-up at 6 months, there was 1 patient in group 2 who had developed reherniation and thus underwent an open lumbar discectomy. No patient in either group got a postoperative infection, dural tear, or delayed neurological deterioration. No patient was observed who showed hypertension, glucose intolerance, wound problem, or gastrointestinal discomfort, which are complications related to use of steroids.
DISCUSSION
B
Steroids reduce inflammation and block afferent C fiber nociception and vascular responses toward inflammations.15–17 Based on these action mechanisms, the effects of epidural steroid application after a lumbar discectomy have been studied
9 8 7
7.80± 1.34 7.63± 1.54
VAS (leg)
6 5
Group I
4
* P=0.020
3
2.27± 1.27
2
1.59± 1.31
1
1.69± 1.11
1.38± 0.98
1.39± 1.02
1.18± 1.03
0 Pre op
Post 1w
Group II
† P=0.032
Post 4w
Post 26w
Time
Figure 4. Mean values of VAS of back (A) and leg (B) pain after percutaneous endoscopic lumbar discectomy at the follow-up. VAS indicates visual analogue scale. *Significant difference at 1 week of follow up between groups (P < 0.05).
Figure 5. Mean values of ODI scores after percutaneous endoscopic lumbar discectomy at the follow-up. ODI indicates Oswestry Disability Index.
†Significant difference at 4 weeks of follow up between groups (P < 0.05).
*Significant difference at 1 week of follow up between groups (P < 0.01).
E862
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August 2015
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E862
03/07/15 10:04 AM
RANDOMIZED TRIAL
Steroids After Endoscopic Discectomy • Shin et al
P=0.024*
7
6.48± 4.88
6
Time
5
4.45± 3.59
P
RANDOMIZED TRIAL
Epidural Steroids After a Percutaneous Endoscopic Lumbar Discectomy Sang-Ha Shin, MD,* Byeong-Wook Hwang, MD, PhD,† Han-Joong Keum, MD,* Sang-Jin Lee, MD, PhD,† Sang-Joon Park, MD,† and Sang-Ho Lee, MD, PhD*
Study Design. Randomized controlled study from a single surgeon. Objective. The objective of the present study is to assess the effectiveness of the administration of epidural steroids in patients who undergo a percutaneous endoscopic lumbar discectomy (PELD) because of a herniated lumbar disc. Summary of Background Data. Steroids are drugs that show strong anti-inflammatory effects; in specific, the effects of epidural steroid application after an open lumbar discectomy have been studied extensively. However, no study has been conducted on the effects of perioperative epidural steroids after PELD. Methods. One hundred patients who had undergone a PELD because of a herniated lumbar disc were randomized into 2 groups. Patients in group 1 were subjected to an epidural steroid application after a PELD, whereas patients in group 2 were treated with saline after a PELD. Results. There was a significant decrease in visual analogue scale (VAS) scores (back, leg) and Oswestry Disability Index at all examinations (P < 0.01). When comparing the 2 groups, group 1 showed lower levels of VAS scores (back) in all examinations than group 2 but was not statistically significant (P = 0.257). In VAS score (leg), group 1 showed a significant decrease compared with the group 2 at 1 and 4 weeks of follow-up examination (P = 0.020, P = 0.032). In Oswestry Disability Index, group 1 showed a significant decrease compared with the group 2 at 1-week follow-up examination (P < 0.01). The mean hospital stay was statistically significantly shorter in group 1 (P < 0.01). The mean periods before returning to work for those who returned to work in group 1 and group 2 were 4.45 ±
From the *Department of Neurosurgery, Wooridul Spine Hospital, Seoul, Korea; and †Department of Neurosurgery, Busan Wooridul Spine Hospital, Busan, Korea. Acknowledgment date: November 5, 2013. First revision date: April 16, 2014. Second revision date: June 17, 2014. Acceptance date: July 29, 2014. The manuscript submitted does not contain information about medical device(s)/drug(s). Wooridul Spine Foundation grant funds were received to support this work. No relevant financial activities outside the submitted work. Address correspondence and reprint requests to Sang-Ha Shin, MD, Department of Neurosurgery, Wooridul Spine Hospital, 445, Hakdong-ro, Gangnam-gu, Seoul, 135-951, South Korea; E-mail: [email protected] DOI: 10.1097/BRS.0000000000000990 Spine
3.59 weeks and 6.48 ± 4.88 weeks, respectively, when measured at follow-up at 6 months; the period in group 1 was statistically significantly shorter (P = 0.024). Conclusion. Epidural steroids after a PELD reduce back pain and leg pain while improving functional outcomes in the short-term postsurgery period. Key words: steroids, endoscopic discectomy, lumbar disc herniation, clinical results. Level of Evidence: 2 Spine 2015;40:E859–E865
T
he back pain and leg pain that accompany lumbar disc herniation are known to generally occur because of physical pressure on the nerves of the herniated nucleus pulposus and inflammatory reactions.1 Patients experiencing herniated nucleus pulposus are surgically treated when they do not respond to conservative treatment. Although the removal of herniated discs through surgery removes physical pressure on the nerves, the inflammatory reactions remain even after surgery, and the perineural fibrosis that progresses after surgery can induce persistent pain and physical disabilities.2 Therefore, many studies have been conducted with a goal of finding a method to relieve pain by reducing inflammatory reactions and late peridural scar formation through the application of epidural steroids after an open lumbar discectomy.3–11 Although somewhat controversial, many studies have reported on perioperative epidural steroids as a method to relieve pain in the short-term postoperative period. After Kambin and Gellman12 reported on minimal access surgery in lumbar disc herniation in 1983, endoscopic discectomy has rapidly gained worldwide popularity because of the development of endoscopic devices and an increased need by patients. This procedure is widely performed by interventional pain physicians as well as by spine surgeons because it requires no general anesthesia or admission to a hospital. However, no study has yet focused on the effects of perioperative epidural steroids after an endoscopic discectomy. Thus, the authors performed perioperative epidural steroid application after percutaneous endoscopic lumbar discectomy (PELD) and tried to examine the effects and characteristics of the application. www.spinejournal.com
E859
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E859
03/07/15 10:04 AM
RANDOMIZED TRIAL MATERIALS AND METHODS Subjects This study was approved by our institutional review board. All procedures were performed by a single surgeon and informed consent was obtained from each patient. One hundred twenty-six eligible patients diagnosed at our institution with herniated discs during a period from October 2010 to March 2012 were assessed.
Inclusion Criteria Patients in the following cases were included in the present study: if the patient's symptom duration was at least 6 weeks and conservative treatment failed, if the patient had soft disc and contained disc herniation limited to a level that was located at the paracentral or central portion, or if the patient had low-grade extruded disc herniation, or more specifically, the degree of craniocaudal migration was smaller than the height of posterior marginal disc space measured in the magnetic resonance imaging (MRI) sagittal plane. Patients in the following cases were excluded from the present study: if the patient showed profound motor weakness, including foot drop, calcified, sequestrated, or recurrent disc herniation; if an endoscopic foraminoplasty was considered because of bony obstacles; disc herniation was accompanied by spinal stenosis or spinal instability; spondylolisthesis; or disc herniation accompanied by diabetes mellitus. Patients who were immunocompromised, under anticoagulant therapy, diagnosed with an uncontrolled acute or
Steroids After Endoscopic Discectomy • Shin et al
chronic medical illness, or in a pregnant or lactating state were also excluded. Twenty-two patients who did not meet the inclusion criteria and 4 patients who refused to participate in the study were excluded, and thus 100 patients were registered. During the registration period, patients’ age, sex, symptom duration, medical/surgical history, visual analogue scale (VAS) scores of leg and back, and previous history of epidural injections were examined; radiological, physical, and neurological examinations were also conducted. The 100 registered patients were randomly assigned to group 1 (n = 50) or group 2 (n = 50). Block randomization was done using a computerized sequence generator. The operator and the patient were blinded from group assignment. One patient in group 1 who showed uncontrolled bleeding while a PELD was performed and 1 patient in group 2 who showed persistent pain due to insufficient decompression were converted into open surgery and thus were excluded from analyses. Group 1 patients were subjected to epidural steroid application after a PELD and group 2 patients were subjected to a saline application after a PELD. VAS scores of leg and back and Oswestry Disability Index (ODI) were examined in the patients in the 2 groups at follow-up at 1 week, 4 weeks, and 26 weeks postsurgery. One patient in group 2 who underwent an open discectomy because of recurrent disc herniation was excluded from analyses. Thus, 49 patients in group 1 and 48 patients in group 2 were examined. In addition, postoperative hospital stays and returns to work were examined in all patients (Figure 1). Clinical results from follow-up were
Figure 1. Flowchart of the patient. PELD indicates percutaneous endoscopic lumbar discectomy.
E860
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August 2015
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E860
03/07/15 10:04 AM
RANDOMIZED TRIAL
Steroids After Endoscopic Discectomy • Shin et al
was encouraged for 6 weeks after the procedure. Patients were advised to refrain from sexual activities and daily ambulation of greater than 4 km for at least 2 weeks, and sitting on the floor for any amount of time or on a chair for more than 1 hour was forbidden.
Statistical Analysis Clinical results were statistically analyzed using the SPSS Win 14.0 program. Data were analyzed into arithmetic means and standard deviations, and repeated measures analysis of variance and t tests were used for statistical analyses. Repeated measures analysis of variance was used to test the differences between both groups in VAS scores (leg and back) and ODI. T tests were used to test the differences between both groups in outcomes of hospital stay and returning to work. Results were considered statistically significant if the P value was less than 0.05.
RESULTS Figure 2. Fluoroscopic view. The radiocontrast agent is filled into the S1 root and into the thecal sac from the decompressed disc space.
blinded from the patient and the operator and were collected and analyzed by a separate researcher.
Surgical Technique and Epidural Steroid Application The conventional transforaminal endoscopic discectomy technique was implemented through the foraminal window in all patients.13,14 After sufficient decompression and identification of epidural pulsation, a radiocontrast agent was injected through the obturator cannulation using a syringe and the epidural filling pattern was checked (Figure 2). Thereafter, a solution made by mixing 1 mLof triamcinolone (40 mg) with 4 mL of saline was administered to each patient in group 1, and 5 mL of saline was administered to each patient in group 2 (Figure 3). The patients were taken out of the operating room after subcutaneous sutures and dressing. A postoperative MRI was conducted on the day of surgery in all patients. The patients were permitted to go home when there was no bleeding on MRI, successful decompression was shown, and the patients’ pain was tolerable. One gram of ceftezole was injected as a prophylactic antibiotic in all patients 1 hour prior to the procedure. Application of a spinal-supporting corset
Of the 50 patients assigned to group 1, 21 were male and 29 were female, and the patients’ average age was 34.52 (range: 19–57) years. Their mean symptom duration was 22.36 (range: 6–104) days and their involved levels were L3–L4, L4–L5, and L5–S1 in 4, 35, and 11 patients, respectively. Thirty-seven patients had a history of epidural steroid injection. Of the 50 patients assigned to group 2, 19 were male and 31 were female, and the patients’ average age was 35.84 (range: 18–61) years. Their mean symptom duration was 20.04 (range: 6–78) days and their involved levels were L3–L4, L4–L5, and L5–S1 in 5, 36, and 9 patients. Thirtytwo patients had a history of epidural steroid injection. The demographic data of the 2 randomized groups were not statistically significantly different (Table 1). Except for 1 patient in group 1 who showed uncontrolled bleeding during an endoscopic discectomy and 1 patient in group 2 who showed persistent pain due to insufficient decompression, successful decompression was identified through postoperative MRI in all of the patients. There was a significant decrease in VAS scores (back and leg) and ODI at all examinations (P < 0.01). When comparing the 2 groups, group 1 showed lower levels of VAS scores (back) in all examinations than those in group 2 but was not statistically significant (P = 0.257) (Figure 4A). In VAS scores (leg), group 1 showed a significant decrease compared with
Figure 3. Epidural steroid application. Epidural steroids can be easily injected through obturator cannulation using a syringe. Spine
www.spinejournal.com
E861
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E861
03/07/15 10:04 AM
RANDOMIZED TRIAL
Steroids After Endoscopic Discectomy • Shin et al
TABLE 1. Patient Demographics P
Group 1
Group 2
50
50
21/29
19/31
0.687
Mean age (yr)
34.52 (19–57)
35.84 (18–61)
0.530
Mean symptom duration (wk)
22.36 (6–104)
20.04 (6–78)
0.496
L3–L4
4
5
L4–L5
35
36
L5–S1
11
9
37
32
No. patients Sex (male/female)
Involved level
Previous history of epidural steroid injection
group 2 at 1 and 4 weeks of follow-up examination (P = 0.020, P = 0.032), but this association was not statistically significant at 26 weeks of follow-up (P = 0.347) (Figure 4B). In ODI, group 1 showed a significant decrease compared with the group 2 at 1-week follow-up examination (P < 0.01), but this association was not statistically significant at 4 and 26 weeks of follow-up (P = 0.223, P = 0.641) (Figure 5).
0.284
The mean hospital stays were 1.49 ± 0.68 days in group 1 and 2.14 ± 0.89 in group 2, respectively, and the value in group 1 was statistically significantly shorter (P < 0.01). At the 6-month follow-up period, 47 patients returned to work in group 1 and 46 in group 2, and their mean periods of returns to work were 4.45 ± 3.59 and 6.48 ± 4.88 in group 1 and group 2, respectively, and the value in group 1 was statistically significantly shorter (P = 0.024) (Figure 6). During the follow-up at 6 months, there was 1 patient in group 2 who had developed reherniation and thus underwent an open lumbar discectomy. No patient in either group got a postoperative infection, dural tear, or delayed neurological deterioration. No patient was observed who showed hypertension, glucose intolerance, wound problem, or gastrointestinal discomfort, which are complications related to use of steroids.
DISCUSSION
B
Steroids reduce inflammation and block afferent C fiber nociception and vascular responses toward inflammations.15–17 Based on these action mechanisms, the effects of epidural steroid application after a lumbar discectomy have been studied
9 8 7
7.80± 1.34 7.63± 1.54
VAS (leg)
6 5
Group I
4
* P=0.020
3
2.27± 1.27
2
1.59± 1.31
1
1.69± 1.11
1.38± 0.98
1.39± 1.02
1.18± 1.03
0 Pre op
Post 1w
Group II
† P=0.032
Post 4w
Post 26w
Time
Figure 4. Mean values of VAS of back (A) and leg (B) pain after percutaneous endoscopic lumbar discectomy at the follow-up. VAS indicates visual analogue scale. *Significant difference at 1 week of follow up between groups (P < 0.05).
Figure 5. Mean values of ODI scores after percutaneous endoscopic lumbar discectomy at the follow-up. ODI indicates Oswestry Disability Index.
†Significant difference at 4 weeks of follow up between groups (P < 0.05).
*Significant difference at 1 week of follow up between groups (P < 0.01).
E862
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August 2015
Copyright © 2015 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. SPINE131309_LR E862
03/07/15 10:04 AM
RANDOMIZED TRIAL
Steroids After Endoscopic Discectomy • Shin et al
P=0.024*
7
6.48± 4.88
6
Time
5
4.45± 3.59
P
