Percutaneous Endoscopic Lumbar Discectomy (PELD) / 한양의대학술지

The percutaneous endoscopic lumbar discectomy (PELD) is already being applied to treat almost all types of lumbar disc herniations, ranging from soft contained disc herniation, to migrated disc herniation, and eventually to foraminal and extraforaminal disc herniations. Its concept has already shifted from an indirect central decompression to a direct epidural targeted fragmentectomy with its clinical outcomes comparable to those of conventional open surgery. However, despite the good surgical outcomes reported for this endoscopic procedure for various lumbar spinal pathologies, its procedure still appears to be somewhat complicated for most spine surgeons. This phenomenon might be attributable to the fact that, apart from the technical aspect of the procedure, the surgeons are not familiar with the proper selection of patients. In this article, we have dealt with the basic principle and technique for various surgical conditions. Although these descriptions are totally based on our experiences and therefore have not been statistically analyzed.

Percutaneous Endoscopic Lumbar Discectomy (PELD) Using Interlaminar Approach in Lumbar Disc Herniation: Endoscopic Laminotomy / 대한척추외과학회지

STUDY DESIGN: Retrospective study OBJECTIVES: This study examined the post-operative results of interlaminar percutaneous endoscopic lumbar discectomy (PELD) with or without endoscopic laminotomy in lumbar disc herniation. SUMMARY OF LITERATURE REVIEW: In addition to the technical feasibility, the indications of PELD surgery are usually the same as those for open discectomy. MATERIALS AND METHODS: From January 2005 to August 2006, 62 cases treated with PELD using an interlaminar approach due to lumbar disc herniation were examined. The mean age of the subjects was 40.1 years (18-70) and the mean follow up period was 32.6 months (24-44). Thirty-four and 28 herniated discs were extracted from L4-L5 and L5-S1, respectively. The clinical results were evaluated using MacNab's criteria. RESULTS: The herniated discs were accessible in all cases. Excellent and good results were obtained in 85% (53 cases) of patients but 15% of patients (9 cases) showed unsatisfactory results or needed revision. There were 4 cases of incomplete removal, 2 cases of recurrence and 4 cases of persistent low back pain due to associated degenerative pathologies. Additional surgery was required in 7 cases which were open discectomy in 5 cases (3 cases of 4 incomplete removal and 2 of recurrence). There was one case of PLIF and 1 additional decompression. Cauda equina syndrome occurred in one case who underwent subsequent wide decompression and open discectomy. CONCLUSIONS: interlaminar PELD using endoscopic laminotomy is an effective method for treating lumbar disc herniation with moderate up and down migration. The clinical success rate can be improved by selecting patients with accessible discs and excluding those with an associated pathology.

Entry Point and Approaching Angle of Working Cannula in Endoscopic Lumbar Disecectomy / 대한척추외과학회지

STUDY DESIGN: A retrospective study. OBJECTIVES: We report the efficacy of the entry point and approach angle of a working cannula using preoperative prone abdominal computer tomography (PACT). SUMMARY OF LITERATURE REVIEW: To date, there are no reports on the entry point and approach angle of a working cannula when performing transforaminal percutaneous endoscopic lumbar discectomy (TPELD) with consideration of the individual anatomic variations and characteristics of herniated disc and surgical instruments. MATERIALS AND METHODS: Cases of herniated intervertebral discs from L4-5, who have previously undergone PACT before TPELD, were included. A total of 25 patients were observed over a 1 year period. The entry point and approaching angle of the working cannula with PACT were calculated, and the results were applied to the TPELD. The clinical results were assessed 1 month after surgery using the VAS, ODI and MacNab criteria, and were confirmed by a radiology and MRI examination. RESULTS: The preoperative measured data using PACT showed that the mean approaching distance and mean approaching angle of the working cannula were 12.4 cm and 75.4 degree, respectively. The VAS improved from a mean of 8.1 preoperatively to a mean of 2.3 12 months after surgery. The ODI improved from a mean of 59 preoperatively to a mean of 24 at 12 months after surgery. According to the MacNab criteria, all patients were classified as either excellent and good during the follow up periods. The extruded disc of all patients had been well removed according to the MRI scan performed 1 month after surgery. CONCLUSIONS: The scientific approach method using PACT based on the characteristics of patients and surgical instruments can be performed easily and accurately, and access and decompress the extruded disc directly.

Percutaneous Endoscopic Discectomy for Lumbar Disc Herniation / 대한척추외과학회지

Percutaneous endoscopic lumbar discectomy is a widely used procedure. In addition to the surgical techniques, the proper selection of the patients and appropriate approaching portal is important improving the clinical results. The choice of the approaching portal is related to the distance of migration and spinal canal encroachment in addition to the type of herniation type. In addition, it is essential to know the anatomic characteristics at each level of the lumbar spine in addition to the indications of the various approaching portals.

Percutaneous Endoscopic Interlaminar Discectomy for L5-S1 Disc Herniation: Axillary Approach and Preliminary Results

OBJECTIVE: The purpose of this study was to describe a surgical technique of axillary approach of percutaneous endoscopic interlaminar discectomy for L5-S1 disc herniation and its preliminary results. METHODS: From July 2002 to September 2003, 101 patients with lumbar radiculopathy due to L5-S1 disc herniation, who were treated by percutaneous interlaminar endoscopic discectomy, were retrospectively reviewed. There were 57 males and 44 females with a mean age of 44.8 years (range, 18 to 62 years). The surgery consisted of needle insertion into the epidural space via the interlaminar space, sequential dilatation, and endoscopic discectomy through the axillary area of the S1 root. RESULTS: The mean follow-up period was 14.5 months and the average surgical time was 41 min. According to the modified Macnab criteria, 44 patients (43.6%) had excellent outcomes, 49 (48.5%) had good results and only 8 (7.8%) had fair or poor outcomes. Four patients had a revision microdiscectomy due to incomplete removal of disc fragment. There were no major complications related to this surgical approach. CONCLUSION: Axillary approach of percutaneous endoscopic interlaminar discectomy is safe and effective procedure for the treatment of L5-S1 disc herniation. It combines the advantages of MED and conventional percutaneous endoscopic discectomy.

Percutaneous Endoscopic Thoracic Discectomy: Posterolateral Transforaminal Approach

OBJECTIVE: Development of diagnostic tools has resulted in early detection of thoracic disc herniations(TDH) even when the herniated disc is soft in consistency. In some of the cases, it is considered better not to opt for surgical treatment due to the unduly high morbidity and potential complications associated with conventional approaches. The authors have applied percutaneous endoscopic thoracic discectomy(PETD) technique to soft TDHs in order to avoid the morbidity associated with conventional approaches. METHODS: Eight consecutive patients (range, 31 to 75 years) with soft lateral or central TDH (from T2-3 to T11-12) underwent PETD between May 2001 and June 2004. The patient was positioned in a prone position with intravenous sedation and local anesthetic infiltration. The authors introduced a cannula into the thoracic intervertebral foramen using endoscopic foraminoplasty technique. Discectomy was performed with mechanical tools and a laser under continuous endoscopic visualization and fluoroscopic guidance. Functional status was assessed preoperatively and postoperatively using the Oswestry Disability Index(ODI). RESULTS: The mean ODI scores improved from 52.8 before the surgery to 25.8 at the final follow-up. In cases of myelopathy, long tract signs showed improvement. The mean operative time was 55 minutes, and no patient required conversion to open surgery. CONCLUSION: The technique allows a smaller incision and less morbidity. Soft TDH is amenable to this minimally invasive approach in selected patients with myeloradiculopathy.

Cauda Equina Syndrome After Percutaneous Endoscopic Discectomy At L5-S1: A case Report / 대한척추외과학회지

The Cauda Equina syndrome after spine surgery is a relatively uncommon condition, but it is a serious complication that needs emergency treatment. A 35-year-old woman was transferred to our hospital and she presented with decreased perianal sensation and rectal tone after percutaneous endoscopic discectomy. Magnetic resonance image showed that the dura sac was compressed by herniated disc material at L5-S1. After performing emergency open discectomy for the cauda eguina syndrome, the patient's neurologic symptoms were completely resolved at 12 months follow-up. There has been no previous report on Cauda Equina syndrome after percutaneous endoscopic discectomy, and so we report here on one case.

Clinical Results of Percutaneous Endoscopic Discectomy in Herniated Intervertebral disc of Lumbar Spine / 대한척추외과학회지

STUDY DESIGN: A retrospective study. OBJECTIVES: To assess the clinical outcomes and roentgenographic changes after an percutaneous endoscopic discetomy of an intervertebral disc herniation of the lumbar spine. SUMMARY OF LITERATURE REVIEW: Percutaneous endoscopic discectomy can preserve normal posterior element in the treatment for herniated intervertebral disc of lumbar spine. MATERIALS AND METHODS: Fifty two patients (41 men, 11 women), who had been treated with percutaneous endoscopic discectomy due to a herniated intevertebral disc of the lubar spine and were followed at least 1 year, were enrolled in this study. The mean age was 26.5 years (21~45) and the mean follow-up period was 42 months (12~76). Fifteen, 28 and 9 herniated discs were extracted from L3-L4, L4-L5 and L5-S1, respectively. RESULTS: After the percutaneous endoscopic discectomy, excellent and good results were obtained in 71% (37 cases) of patients but 9% (5 cases) of patients reported poor results. A roentgenographic assessment at the final follow-up showed no instability and no degenerative spondylotic finding. However, the intervertebral disc space was decreased in only 1 case. CONCLUSION: An percutaneous endoscopic discectomy is an effective method for treating a herniated intervertebral disc of the lumbar spine. However, prudent patient selection is very important for achieving good results.

Safe Approaching Angle and Distance in Percutaneous Endoscopic Discectomy / 대한척추외과학회지

STUDY DESIGN: A retrograde study, using Computerized Tomography (CT), to evaluate a safer approaching angle and distance for a percutaneous endoscopic discectomy. OBJECTIVES: To measure the safest approaching angle and distance in a percutaneous endoscopic discectomy at each vertebra level in Koreans. LITERATURE REVIEW SUMMARY: Some authors have shown an approaching angle of between 25 to 30 degrees, but reports on Koreans patients are very rare. MATERIALS AND METHODS: 200 cases of abdomino-pelvic CT were investigated. The minimal angle of safe approach was composed of two lines, one horizontal line passing through the mid point in the posterior cortex of upper vertebra, with the other extending passed the mid point of posterior cortex in the upper vertebra to the dorsal margin of the retroperitoneal fat or peritoneum. The maximal distance for a safe approach was measured from the end of spinous process to the point where the extended former second line crosses the skin. The minimal angles and maximal distances for safe approaches in males and females, from the right and left sides, at each level of the intervertebral space and in groups according to the BMI were compared. RESULTS: Females had a larger mean minimal angle for a safe approach (14.7 degrees) than that for males (9.6 degrees). However, no differences were observed between the right (12.0 degrees) and left sides (12.4 degrees). At each vertebral level, L2-3(16.4 degrees), L3-4(11.3 degrees) and L4-5(8.8 degrees), significant differences were observed. However, obesity had no influence on the different angles for a safe approach. The maximal distances for safe approaches were 12.9 and 12,6cm in males and female, 12.8 cm in for both of the right and left sides, and 11.8, 13.0 and 13.6cm in L2-3, L3-4 and L4-5, respectively. No differences were observed in any of the above group, but the more obese group had a longer distance. CONCLUSIONS: Females and the upper level of the intervertebral space had larger minimal angles for a safe approach, but there were no differences in relation to gender, direction and obesity. All the maximal distances for safe approaches were the same in males, females, right and left, and at each level of the intervertebral space, but the more obese group had a longer distance. A safer zone for the approach in a percutaneous endoscopic lumbar discectomy can be taken, considering the gender, vertebra level and obesity.

Safe Approaching Angle and Distance in Percutaneous Endoscopic Discectomy / 대한척추외과학회지

STUDY DESIGN: A retrograde study, using Computerized Tomography (CT), to evaluate a safer approaching angle and distance for a percutaneous endoscopic discectomy. OBJECTIVES: To measure the safest approaching angle and distance in a percutaneous endoscopic discectomy at each vertebra level in Koreans. LITERATURE REVIEW SUMMARY: Some authors have shown an approaching angle of between 25 to 30 degrees, but reports on Koreans patients are very rare. MATERIALS AND METHODS: 200 cases of abdomino-pelvic CT were investigated. The minimal angle of safe approach was composed of two lines, one horizontal line passing through the mid point in the posterior cortex of upper vertebra, with the other extending passed the mid point of posterior cortex in the upper vertebra to the dorsal margin of the retroperitoneal fat or peritoneum. The maximal distance for a safe approach was measured from the end of spinous process to the point where the extended former second line crosses the skin. The minimal angles and maximal distances for safe approaches in males and females, from the right and left sides, at each level of the intervertebral space and in groups according to the BMI were compared. RESULTS: Females had a larger mean minimal angle for a safe approach (14.7 degrees) than that for males (9.6 degrees). However, no differences were observed between the right (12.0 degrees) and left sides (12.4 degrees). At each vertebral level, L2-3(16.4 degrees), L3-4(11.3 degrees) and L4-5(8.8 degrees), significant differences were observed. However, obesity had no influence on the different angles for a safe approach. The maximal distances for safe approaches were 12.9 and 12,6cm in males and female, 12.8 cm in for both of the right and left sides, and 11.8, 13.0 and 13.6cm in L2-3, L3-4 and L4-5, respectively. No differences were observed in any of the above group, but the more obese group had a longer distance. CONCLUSIONS: Females and the upper level of the intervertebral space had larger minimal angles for a safe approach, but there were no differences in relation to gender, direction and obesity. All the maximal distances for safe approaches were the same in males, females, right and left, and at each level of the intervertebral space, but the more obese group had a longer distance. A safer zone for the approach in a percutaneous endoscopic lumbar discectomy can be taken, considering the gender, vertebra level and obesity.

The Long Term Outcome of Percutaneous Endoscopic Discectomy

Between January 1995 and May 1998, 177 patients with proven lumbar disc herniation were treated by microdiscectomy or by percutaneous endoscopic discectomy(PED). Among them, 43(24.2%) patients underwent PED and were followed for long term outcome. We included only those patients who were followed up more than 13 months. Three patients who did not improved immediately after PED and underwent microdiscectomy were excluded for this study. Of remaining 40 patients, there were 22 men and 18 women who ranged in age from 23 to 68 years (mean 38.1 years). The disc herniations were located at L1-2(1), L2-3(1), L3-4(1), L4-5(26) and L5-S1(11). Three patients were treated by biportal approach. The mean follow up period was 34.7 months(range 13-47 months). Overall, excellent and good results were achieved in 12(30%) and 19(47.5%) patients, and fair and poor results in 7(17.5%) and 2(5%) patients, respectively. Thirty-eight(95%) patients returned to their previous works and the mean duration was 5.7 months. Thirty-three(82.5%) patients answered that they would recommend this procedure to others. There was no complication except for one patient who suffered from discitis. The indication of PED is restricted to contained or small subligamentous lumbar disc herniation without stenosis, spondylolisthesis and sequestration. PED can be performed under local anesthesia and tissue trauma, risk of epidural scarring, hospitalization time and postoperative morbidity are minimal. The result of the present study justify the assumption that PED can be a surgical alternative for patients suitable for its indications.

Percutaneous Endoscopic Discectomy Compared to Microsurgical Discectomy: Preliminary Results

To help clarify the comparative effects of percutaneous endoscopic discectomy and microsurgical discectomy in the treatment of lumbar disc herniation, the authors studied 37 consecutive patients with discogenic symptoms who had not responded to conservative treatment. Their indications are restricted to discogenic root compression with"contained"or small"noncontained"lumbar disc. Patients with sequestrated disc, spinal stenosis, or spondylolisthesis were excluded. All patients underwent magnetic resonance imaging and if the radiological interpretation was confused with extruded migrated disc, a discogram was also obtained. Of the 37 patients, 18 underwent percutaneous endoscopic discectomy and 19, microsurgical discectomy. In order to compare the efficacy of the two methods, both groups were investigated. Disc herniations were located at L4-5(24 patients), L5-S1(11 patients), or L4-5 and L5-S1(2 patients). With regard to age and sex distribution, preoperative complaints, and clinical symptoms, there were no differences between the two groups. At the last follow-up evaluation after percutaneous endoscopic discectomy, low back pain had disappeared in three patients(17.6%), sciatica in nine(50.0%), sensory deficits in two(16.7%), motor deficits in three(42.5%), and reflex differences in one (50%). After microsurgical discectomy, low back pain had disappeared in one patient(5.6%), sciatica in nine(47.4%), sensory deficits in five(33.3%), motor deficits in six(66.7%), and reflex differences in three(75.0%). In 83.3% of patients in the percutaneous endoscopic discectomy group, the outcome was successful(excellent or good result), compared with 78.9% of those who had undergone microsurgical discectomy. One patient in the percutaneous endoscopic discectomy group suffered from discitis. For patients with"contained"or slight subligamentous lumbar disc herniations, percutaneous endoscopic discectomy offers a surgical alternative.