Transforaminal endoscopic decompression for radiculopathy secondary to intracanal noncontained lumbar disc herniations: outcome and technique

Clinical outcomes of percutaneous endoscopic surgery for lumbar discal cyst

OBJECTIVE

Discal cyst is rare and causes indistinguishable symptoms from lumbar disc herniation. The clinical manifestations and pathological features of discal cyst have not yet been completely known. Discal cyst has been treated with surgery or with direct intervention such as computed tomography (CT) guided aspiration and steroid injection. The purpose of this study is to evaluate the safety and efficacy of the percutaneous endoscopic surgery for lumbar discal cyst over at least 6 months follow-up.

METHODS

All 8 cases of discal cyst with radiculopathy were treated by percutaneous endoscopic surgery by transforaminal approach. The involved levels include L5-S1 in 1 patient, L3-4 in 2, and L4-5 in 5. The preoperative magnetic resonance imaging and 3-dimensional CT with discogram images in all cases showed a connection between the cyst and the involved intervertebral disc. Over a 6-months period, self-reported measures were assessed using an outcome questionaire that incorporated total back-related medical resource utilization and improvement of leg pain [visual analogue scale (VAS) and Macnab's criteria].

RESULTS

All 8 patients underwent endoscopic excision of the cyst with additional partial discectomy. Seven patients obtained immediate relief of symptoms after removal of the cyst by endoscopic approach. There were no recurrent lesions during follow-up period. The mean preoperative VAS for leg pain was 8.25±0.5. At the last examination followed longer than 6 month, the mean VAS for leg pain was 2.25±2.21. According to MacNab' criteria, 4 patients (50%) had excellent results, 3 patients (37.5%) had good results; thus, satisfactory results were achieved in 7 patients (87.5%). However, one case had unsatisfactory result with persistent leg pain and another paresthesia.

CONCLUSION

The radicular symptoms were remarkably improved in most patients immediately after percutaneous endoscopic cystectomy by transforaminal approach.

Percutaneous endoscopic lumbar discectomy via contralateral approach: a technical case report

STUDY DESIGN

Technical case report.

OBJECTIVE

The authors report a new percutaneous endoscopic lumbar discectomy (PELD) technique for the treatment of lumbar disc herniation via a contralateral approach.

SUMMARY OF BACKGROUND DATA

When there are highly down-migrated lumbar disc herniation along just medial to pedicle and narrow ipsilateral intervertebral foramen, the conventional PELD is not easily accessible via ipsilateral transforaminal route.

METHODS

Five patients manifested gluteal and leg pain because of a soft disc herniation at the L4-L5 level. Transforaminal PELD via a contralateral approach was performed to remove the herniated fragment, achieving complete decompression of the nerve root.

RESULTS

The symptom was relieved and the patient was discharged the next day.

CONCLUSION

When a conventional transforaminal PELD is difficult because of some anatomical reasons, PELD via a contralateral route could be a good alternative option in selected cases.

Endoscopic discectomy of L5-S1 disc herniation via an interlaminar approach: Prospective controlled study under local and general anesthesia

Background:

Open discectomy remains the standard method for treatment of lumbar disc herniation, but can traumatize spinal structure and leaves symptomatic epidural scarring in more than 10% of cases. The usual transforaminal approach may be associated with difficulty reaching the epidural space due to anatomical peculiarities at the L5–S1 level. The endoscopic interlaminar approach can provide a direct pathway for decompression of disc herniation at the L5–S1 level. This study aimed to evaluate the clinical results of endoscopic interlaminar lumbar discectomy at the L5–S1 level and compare the technique feasibility, safety, and efficacy under local and general anesthesia (LA and GA, respectively).

Methods:

One hundred twenty-three patients with L5–S1 disc herniation underwent endoscopic interlaminar lumbar discectomy from October 2006 to June 2009 by two spine surgeons using different anesthesia preferences in two medical centers. Visual analog scale (VAS) scores for back pain and leg pain and Oswestry Disability Index (ODI) sores were recorded preoperatively, and at 3, 6, and 12 months postoperatively. Results were compared to evaluate the technique feasibility, safety, and efficacy under LA and GA.

Results:

VAS scores for back pain and leg pain and ODI revealed statistically significant improvement when they were compared with preoperative values. Mean hospital stay was statistically shorter in the LA group. Complications included one case of dural tear with rootlet injury and three cases of recurrence within 1 month who subsequently required open surgery or endoscopic interlaminar lumbar discectomy. There were no medical or infectious complications in either group.

Conclusion:

Disc herniation at the L5–S1 level can be adequately treated endoscopically with an interlaminar approach. GA and LA are both effective for this procedure. However, LA is better than GA in our opinion.

Full endoscopic contralateral transforaminal discectomy for distally migrated lumbar disc herniation

BACKGROUND

Discectomy of distally, inferiorly migrated disc herniations below midpedicle level of the vertebral body in the lower lumbar spine is known to be very difficult by endoscopy. The purpose of this study was to introduce the technical possibility of percutaneous endoscopic lumbar discectomy using a contralateral transforaminal approach for distally migrated disc herniation.

METHODS

We reviewed 12 patients who underwent percutaneous endoscopic lumbar discectomy using the contralateral transforaminal approach for distally migrated disc herniation. Complete removal was verified through postoperative magnetic resonance imaging (MRI) follow-up in all patients. Mean follow-up was 25 months.

RESULTS

Clinical results according to MacNab criteria were excellent in ten patients and good in two. Average visual analogue scale for lower back pain and radicular pain improved from 6.8 and 8.2 preoperatively to 1.5 and 1.4, postoperatively (p < 0.01, respectively).

CONCLUSION

Percutaneous endoscopic lumbar discectomy using contralateral transforaminal approach can be a useful method in patients with distally migrated disc herniation, and endoscopic navigation of anterior epidural space from the contralateral foramen in the lower lumbar spine is technically possible.

Endoscopic minimally invasive neurosurgery: emerging techniques and expanding role through an extensive review of the literature and our own experience - part II: extraendoscopic neurosurgery

BACKGROUND/AIMS

The field of minimally invasive neurosurgery has grown dramatically especially in the last decades. This has been possible, in the most part, due to the advancements in technology especially in tools such as the endoscope. The contemporary classification scheme for endoscopic procedures needs to advance as well.

METHODS

The present classification scheme for neuroendoscopic procedures has become confusing because it mainly describes the use of the endoscope as an assisting device to the microscope. The authors propose an update to the current classification that reflects the independence of the endoscope as a tool in minimally invasive neurosurgery.

RESULTS

The proposed classification groups the procedures as 'intraendoscopic' neurosurgery or 'extraendoscopic' neurosurgery (XEN) in relation to the 'axis' of the endoscope. A review of the literature for the XEN group together with exemplary cases is presented.

CONCLUSION

We presented our proposed classification for the endoscope-only surgical procedures. The XEN group is expanded in this article.

Strategies for Noncontained Lumbar Disc Herniation by an Endoscopic Approach : Transforaminal Suprapedicular Approach, Semi-Rigid Flexible Curved Probe, and 3-Dimensional Reconstruction CT with Discogram

OBJECTIVE

The purpose of this study was to evaluate the efficacy of a transforaminal suprapedicular approach, semi-rigid flexible curved probe, and 3-dimensional reconstruction computed tomography (3D-CT) with discogram in the endoscopic treatment of non-contained lumbar disc herniations.

METHODS

The subjects were 153 patients with difficult, non-contained lumbar disc herniations undergoing endoscopic treatment. The types of herniation were as follows : extraforaminal, 17 patients; foraminal, 21 patients; high grade migration, 59 patients; and high canal compromise, 56 patients. To overcome the difficulties in endoscopic treatment, the anatomic structures were analyzed by 3D reconstruction CT and the high grade disc was extracted using a semi-rigid flexible curved probe and a transforaminal suprapedicular approach.

RESULTS

The mean follow-up was 18.3 months. The mean visual analogue scale (VAS) of the patients prior to surgery was 9.48, and the mean postoperative VAS was 1.63. According to Macnab's criteria, 145 patients had excellent and good results, and thus satisfactory results were obtained in 94.77% cases.

CONCLUSION

In a posterolateral endoscopic lumbar discectomy, the difficult, non-contained disc is considered to be the most important factor impeding the success of surgery. By applying a semi-rigid flexible curved probe and using a transforaminal suprapedicular approach, good surgical results can be obtained, even in high grade, non-contained disc herniations.

Transforaminal endoscopic surgery for symptomatic lumbar disc herniations: a systematic review of the literature

The study design includes a systematic literature review. The objective of the study was to evaluate the effectiveness of transforaminal endoscopic surgery and to compare this with open microdiscectomy in patients with symptomatic lumbar disc herniations. Transforaminal endoscopic techniques for patients with symptomatic lumbar disc herniations have become increasingly popular. The literature has not yet been systematically reviewed. A comprehensive systematic literature search of the MEDLINE and EMBASE databases was performed up to May 2008. Two reviewers independently checked all retrieved titles and abstracts and relevant full text articles for inclusion criteria. Included articles were assessed for quality and outcomes were extracted by the two reviewers independently. One randomized controlled trial, 7 non-randomized controlled trials and 31 observational studies were identified. Studies were heterogeneous regarding patient selection, indications, operation techniques, follow-up period and outcome measures and the methodological quality of these studies was poor. The eight trials did not find any statistically significant differences in leg pain reduction between the transforaminal endoscopic surgery group (89%) and the open microdiscectomy group (87%); overall improvement (84 vs. 78%), re-operation rate (6.8 vs. 4.7%) and complication rate (1.5 vs. 1%), respectively. In conclusion, current evidence on the effectiveness of transforaminal endoscopic surgery is poor and does not provide valid information to either support or refute using this type of surgery in patients with symptomatic lumbar disc herniations. High-quality randomized controlled trials with sufficiently large sample sizes are direly needed to evaluate if transforaminal endoscopic surgery is more effective than open microdiscectomy.

Percutaneous endoscopic lumbar discectomy by transiliac approach: a case report

STUDY DESIGN

Case report.

OBJECTIVE

The authors report a new percutaneous endoscopic lumbar discectomy (PELD) technique for the treatment of lumbar disc herniation with a high iliac crest via a transiliac approach.

SUMMARY OF BACKGROUND DATA

When the iliac crest is high, the L4-L5 and L5-S1 disc spaces are located deep in the pelvis, so they are not easily accessible via a suprailiac route.

METHODS

A 51-year-old man manifested left gluteal and leg pain due to an up-migrated soft disc herniation at the L4-L5 level. Transforaminal PELD via a transiliac approach was performed to remove the herniated fragment, achieving complete decompression of the nerve root.

RESULTS

The symptom was relieved and the patient was discharged the next day.

CONCLUSION

When a conventional transforaminal PELD is impossible due to the presence of a high iliac crest, PELD via a transiliac route could be a alternative option in selected cases.

Transforaminal percutaneous endoscopic lumbar discectomy for upper lumbar disc herniation: clinical outcome, prognostic factors, and technical consideration

BACKGROUND

Compared with lower lumbar disc herniations, upper lumbar disc herniations at L1-L2 and L2-L3 have specific characteristics that result in different surgical outcomes after conventional open discectomy. There are no published studies on the feasibility of percutaneous endoscopic lumbar discectomy for upper lumbar disc herniation. The purpose of this study was to assess the clinical outcome, prognostic factors and the technical pitfalls of PELD for upper lumbar disc herniation.

METHOD

Forty-five patients with a soft disc herniation at L1-L2 or L2-L3 underwent percutaneous endoscopic discectomy. Posterolateral transforaminal endoscopic laser-assisted disc removal was performed under local anesthesia. Clinical outcomes was assessed using the Prolo scale. The prognostic factors associated with outcome were then analyzed.

FINDINGS

The mean follow-up was 38.8 months (range, 25-52 months). The outcome of the 45 patients was excellent in 21 (46.7%), good in 14 patients (31.1%), fair in six patients (13.3%), and poor in four patients (8.9%). Four patients with a poor outcome underwent further open surgery. Mean scores on a visual analog scale decreased from 8.38 to 2.36 (P < 0.0001). Age less than 45 years and a lateral disc herniation were independently associated with an excellent outcome (P < 0.05).

CONCLUSIONS

Patient selection and an anatomically modified surgical technique promote a more successful outcome after percutaneous endoscopic discectomy for upper lumbar disc herniation.

Endoscopic transforaminal suprapedicular approach in high grade inferior migrated lumbar disc herniation

OBJECTIVE

Although endoscopic procedures for lumbar disc diseases have improved greatly, the postoperative outcomes for high grade inferior migrated discs are not satisfactory. Because of anatomic limitations, a rigid endoscope cannot reach all lesions effectively. The purpose of this study was to determine the feasibility of endoscopic transforaminal suprapedicular approach to high grade inferior-migrated lumbar disc herniations.

METHODS

Between May 2006 and March 2008, a suprapedicular approach was performed in 53 patients with high grade inferior-migrated lumbar disc herniations using a rigid endoscope and a semi-rigid flexible curved probe. One-to-four hours after surgery, the presence of remnant discs was checked with MRI. The outcomes were evaluated with the visual analogue scale (VAS) score and the Oswestry Disability Index (ODI) one week after surgery.

RESULTS

The L2-3 level was involved in 2 patients and the L3-4 level was involved in 14 patients, while the L4-5 level was involved in 39 patients. There were single piece-type in 34 cases and a multiple piece-type in 19 cases. Satisfactory results were obtained in all cases. The mean preoperative VAS for leg pain was 9.32+/-0.43 points (range, 7-10 points), whereas the mean ODI was 79.82+/-4.53 points (range, 68-92 points). At the last follow-up examination, the mean postoperative VAS for leg pain was 1.78+/-0.71 points and the mean postoperative ODI improved to 15.27+/-3.82 points.

CONCLUSION

A high grade inferior migrated lumbar disc is difficult to remove sufficiently by posterolateral endoscopic lumbar dscectomy using a rigid endoscope. However, a satisfactory result can be obtained by applying a transforaminal suprapedicular approach with a flexible semi-rigid curved probe.

Full-endoscopic interlaminar and transforaminal lumbar discectomy versus conventional microsurgical technique: a prospective, randomized, controlled study

STUDY DESIGN

Prospective, randomized, controlled study of patients with lumbar disc herniations, operated either in a full-endoscopic or microsurgical technique.

OBJECTIVE

Comparison of results of lumbar discectomies in full-endoscopic interlaminar and transforaminal technique with the conventional microsurgical technique.

SUMMARY OF BACKGROUND DATA

Even with good results, conventional disc operations may result in subsequent damage due to trauma. Endoscopic techniques have become the standard in many areas because of the advantages they offer intraoperatively and after surgery. With the transforaminal and interlaminar techniques, 2 full-endoscopic procedures are available for lumbar disc operations.

METHODS

One hundred seventy-eight patients with full-endoscopic or microsurgical discectomy underwent follow-up for 2 years. In addition to general and specific parameters, the following measuring instruments were used: VAS, German version North American Spine Society Instrument, Oswestry Low-Back Pain Disability Questionnaire.

RESULTS

After surgery 82% of the patients no longer had leg pain, and 14% had occasional pain. The clinical results were the same in both groups. The recurrence rate was 6.2% with no difference between the groups. The full-endoscopic techniques brought significant advantages in the following areas: back pain, rehabilitation, complications, and traumatization.

CONCLUSION

The clinical results of the full-endoscopic technique are equal to those of the microsurgical technique. At the same time, there are advantages in the operation technique and reduced traumatization. With the surgical devices and the possibility of selecting an interlaminar or posterolateral to lateral transforaminal procedure, lumbar disc herniations outside and inside the spinal canal can be sufficiently removed using the full-endoscopic technique, when taking the appropriate criteria into account. Full-endoscopic surgery is a sufficient and safe supplementation and alternative to microsurgical procedures.

Full-endoscopic cervical posterior foraminotomy for the operation of lateral disc herniations using 5.9-mm endoscopes: a prospective, randomized, controlled study

STUDY DESIGN

Prospective, randomized, controlled study of patients with lateral cervical disc herniations, operated either in a full-endoscopic posterior or conventional microsurgical anterior technique.

OBJECTIVE

Comparison of results of cervical discectomies in full-endoscopic posterior foraminotomy technique with the conventional microsurgical anterior decompression and fusion.

SUMMARY OF BACKGROUND DATA

Anterior cervical decompression and fusion is the standard procedure for operation of cervical disc herniations with radicular arm pain. Mobility-preserving posterior foraminotomy is the most common alternative in the case of lateral localization of the pathology. Despite good clinical results, problems may arise due to traumatization of the access. Endoscopic techniques are considered standard in many areas, since they may offer advantages in surgical technique and rehabilitation. These days, all disc herniations of the lumbar spine can be operated in full-endoscopic technique. With the full-endoscopic posterior cervical foraminotomy a procedures is available for cervical disc operations.

METHODS

One hundred and seventy-five patients with full-endoscopic posterior or microsurgical anterior cervical discectomy underwent follow-up for 2 years. In addition to general and specific parameters, the following measuring instruments were used: VAS, German version North American Spine Society Instrument, Hilibrand Criteria.

RESULTS

After surgery 87.4% of the patients no longer had arm pain, and 9.2% had occasional pain. The clinical results were the same in both groups. There were no significant difference between the groups in the revision or complication rate. The full-endoscopic technique brought advantages in operation technique, preserving mobility, rehabilitation, and traumatization.

CONCLUSION

The recorded results show that the full-endoscopic posterior foraminotomy is a sufficient and safe supplement and alternative to conventional procedures when the indication criteria are fulfilled. At the same time, it offers the advantages of a minimally invasive intervention.

Intervertebral disc: anatomy-physiology-pathophysiology-treatment

This review article describes anatomy, physiology, pathophysiology and treatment of intervertebral disc. The intervertebral discs lie between the vertebral bodies, linking them together. The components of the disc are nucleus pulposus, annulus fibrosus and cartilagenous end-plates. The blood supply to the disc is only to the cartilagenous end-plates. The nerve supply is basically through the sinovertebral nerve. Biochemically, the important constituents of the disc are collagen fibers, elastin fibers and aggrecan. As the disc ages, degeneration occurs, osmotic pressure is lost in the nucleus, dehydration occurs, and the disc loses its height. During these changes, nociceptive nuclear material tracks and leaks through the outer rim of the annulus. This is the main source of discogenic pain. While this is occurring, the degenerative disc, having lost its height, effects the structures close by, such as ligamentum flavum, facet joints, and the shape of the neural foramina. This is the main cause of spinal stenosis and radicular pain due to the disc degeneration in the aged populations. Diagnosis is done by a strict protocol and treatment options are described in this review. The rationale for new therapies are to substitute the biochemical constituents, or augment nucleus pulposus or regenerate cartilaginous end-plate or finally artificial disc implantation..

The learning curve in foraminal endoscopic discectomy: experience needed to achieve a 90% success rate

BACKGROUND

We sought to construct a general methodology for objectively quantifying the learning curve associated with any surgical technique and to determine the number of cases needed to achieve a success rate of 90% for the technique of transforaminal endoscopic lumbar discectomy. To our knowledge, no other studies have observed the learning curve of endoscopic lumbar discectomy by transforaminal approach.

METHODS

We studied the learning curve of 1 orthopedic surgeon who had had experience performing open spine surgery and knee and shoulder arthroscopic surgery, but not endoscopic spine surgery. We studied 144 patients who had an endoscopic lumbar discectomy by transforaminal approach (using the Yeung Endoscopic Surgery System). We evaluated results with modified MacNab criteria and used a questionnaire to determine the patients' satisfaction with the surgery. The average follow-up period was 24 months. We used an algorithm, analyzing the patient outcome and the surgical time evolution, to determine the case at which a success rate of 90% good/excellent results was reached.

RESULTS

The cut for the calculated learning curve was placed at case no. 72; i.e., the results in the first 72 cases were 75% good/excellent, 18% fair, and 7% poor, and the results in the following 72 cases were 90.3% good/excellent, 9.7% fair, and 0% poor.

CONCLUSIONS

A methodology to calculate the learning curve of a surgical procedure was developed. A learning curve of 72 cases was needed to reach the goal of 90% of good/excellent results for transforaminal endoscopic lumbar discectomy.

CLINICAL RELEVANCE

The method developed to establish the learning curve of a surgical procedure, based on outcome and surgical time, may be used to assess any new procedure. With respect to the transforaminal endoscopic technique, the determination of a specific number of cases (72) needed to master (achieve 90% excellent/ good results) could help orient surgeons willing to adopt this technique.

Minimally invasive techniques for the management of lumbar disc herniation

Traditionally, minimally invasive techniques for surgical discectomy have been defined as smaller incisions, tubular retractors, microscopically assisted tissue dissection, and conservative removal of only extruded or sequestered nucleus pulposus with preservation of the annulus. The first truly minimally invasive technique was chymopapain dissolution of the nucleus pulposus. Other percutaneous techniques followed; however, none were as efficacious as the gold standard of microlumbar discectomy until endoscopically visualized methods evolved to allow visualized mechanical discectomy through the foramen. In experienced hands, such a technique is as effective as microlumbar discectomy and results in less surgical morbidity for herniations that are appropriate for this minimally invasive endoscopic surgical portal that completely avoids traumatizing the normal anatomy of the dorsal musculature and ligamentous structures.

Use of newly developed instruments and endoscopes: full-endoscopic resection of lumbar disc herniations via the interlaminar and lateral transforaminal approach

OBJECT

Even with good results, conventional disc operations may result in subsequent damage due to trauma. Endoscopic techniques have become the standard in many areas because of the advantages they offer intraoperatively and postoperatively in rehabilitation. The goal of this prospective study was to examine the expanded technical possibilities of full-endoscopic transforaminal and interlaminar resection of herniated lumbar discs in which the authors used newly developed optics and instruments. The focus was on questions of achieving sufficient decompression, as well as the advantages and disadvantages of the minimally invasive procedure.

METHODS

Two hundred thirty-two patients underwent follow up for 2 years after undergoing surgery. In addition to general and specific parameters, the following measuring instruments were used: a visual analog scale, the German version of the North American Spine Society instrument, and the Oswestry Disability Index of low-back pain disability. Postoperatively 84% of the patients no longer had leg pain, and 12% had only occasional pain. The results of decompression were equivalent to those of conventional procedures. The incidence of traumatization was reduced. Epidural scarring was minimized. The recurrence rate was 6.0%. No serious surgical complications were observed. Resection of the herniated disc was technically possible in all cases in which the new instruments were used.

CONCLUSIONS

The authors view the aforedescribed techniques, which offer the advantages of a truly minimally invasive procedure, as a sufficient and safe supplementation and alternative to conventional procedures, when the appropriate indication criteria are heeded. The new endoscope with its 4.2-mm working channel and corresponding instruments significantly reduced the technical problems.

Clinical outcome of posterolateral endoscopic surgery for pyogenic spondylodiscitis: results of 15 patients with serious comorbid conditions

STUDY DESIGN

Clinical results of posterolateral endoscopic debridement and irrigation followed by percutaneous drainage for pyogenic spondylodiscitis were analyzed.

OBJECTIVES

To report clinical results of transforaminal endoscopic surgery for pyogenic spondylodiscitis and to evaluate the effectiveness of this procedure in treatment of pyogenic spinal infections.

SUMMARY OF BACKGROUND DATA

Pyogenic spinal infections have been increasing due to the development of medical treatment for patients with comorbid medical problems. Common treatments for spinal infections are administration of antibiotics or surgical debridement with bone grafts. There have been no reports, however, regarding the clinical outcome of posterolateral endoscopic treatment for pyogenic spinal infections.

METHODS

Fifteen consecutive patients with pyogenic spondylodiscitis in the thoracic or lumbar spine were enrolled. Preoperative antibiotic treatment had failed in all the patients. The procedures consisted of posterolateral endoscopic debridement and irrigation followed by percutaneous drainage through single portal under the combination of local and intravenous anesthesia. Pain response using visual analog scale (VAS, 0-100 mm), inflammation parameters, and duration of antibiotic therapy were investigated. Radiologic evaluation focused on bony fusion, local kyphosis, disc height reduction, and abscess formation.

RESULTS

All patients showed immediate pain reduction after surgery. Averaged VAS for pain was 86 before surgery and 25 at postoperative 1 week. Average of CRP was 4.00 mg/dL before surgery and 1.88 mg/dL at postoperative 1 week. Averaged duration of antibiotics therapy was 3.7 weeks. Spinal fusion was obtained in 13 patients. Two patients with neurologic deficits due to epidural abscess returned to normal. Preoperative psoas abscess in 6 patients disappeared after surgery on MRI.

CONCLUSIONS

Posterolateral spinal endoscopic debridement and irrigation brought immediate pain reduction and good clinical results to patients who had comorbid medical problems and had pyogenic spondylodiscitis.

An extreme lateral access for the surgery of lumbar disc herniations inside the spinal canal using the full-endoscopic uniportal transforaminal approach-technique and prospective results of 463 patients

STUDY DESIGN

Prospective study of patients with lumbar disc herniations who were operated on with a full-endoscopic uniportal transforaminal approach using an extreme lateral access.

OBJECTIVES

To examine the technical possibilities of an extreme lateral access for full-endoscopic uniportal transforaminal surgery of lumbar disc herniations within the spinal canal. Also, to assess sufficient decompression, and the advantages and disadvantages of the minimally invasive procedure.

SUMMARY OF BACKGROUND DATA

Conventional prolapsed disc operations can result in consecutive damage as a result of traumatization. The usual transforaminal access is posterolateral, and is associated with problems in reaching the epidural space directly with unhindered vision and, thus, with problems of sufficient decompression in lumbar disc herniations within the spinal canal.

METHODS

A total of 463 patients were observed for 1 year. In addition to general and specific parameters, the following measuring instruments were used: visual analog scale, German version North American Spine Society Instrumentarium, Oswestry low back pain disability questionnaire.

RESULTS

There were no complications. Of the patients, 81% reported no longer having leg pain, and 14% had occasional pain. There was no worsening. The results were constant and are equal to those of conventional procedures. No patients presented with neural scarring; 7% had recurrence of the prolapse. The extreme lateral access was necessary to reach the sequestered material.

CONCLUSIONS

The technique presented is an adequate and safe alternative to conventional procedures, and has the advantages of a truly minimally invasive procedure. The extreme lateral access is required for the indications described. There are clear limitations outside these indications. The possibility of selecting an access from posterolateral to extreme lateral now enables surgery of lumbar disc herniations inside and outside the spinal canal.

Posterolateral transforaminal selective endoscopic discectomy and thermal annuloplasty for chronic lumbar discogenic pain: a minimal access visualized intradiscal surgical procedure

BACKGROUND CONTEXT

Chronic lumbar discogenic pain (CLDP) impairs the patient's physical abilities to function within the normal physiologic loading ranges of activities of daily living. The pathogenesis of CLDP is multifactorial and not well understood. Conservative therapeutic regimens often fail to achieve sufficient pain relief. Surgical options vary greatly in surgical invasiveness as well as outcome. Definitive surgical treatment is often 360-degree fusion. The morbidity associated with this approach is significant, considering that only 65% to 80% of patients obtain satisfactory clinical results. This has spawned interest in minimally invasive surgical options, such as intradiscal electrothermal therapy (IDET; ORATEC Interventions, Inc., Menlo Park, CA), but results are conflicting.

PURPOSE

The authors describe their surgical technique of minimal access posterolateral transforaminal selective endoscopic discectomy (SED) and bipolar radiofrequency thermal annuloplasty to treat CLDP. The procedure's rationale is based on the hypothesis that annular defects are the focal points of chronic exposure between neural sensory receptors in the defect and the inflammatogenic nucleus pulposus. In contrast to other percutaneous procedures, this technique allows direct visualization and targeting of the disc nucleus and annular fissures. Our 2-year clinical result is reported.

STUDY DESIGN/SETTING

This is a retrospective review of consecutive surgical cases performed by one surgeon (ATY). The procedures were carried out from January 1997 to December 1999. Each patient has a minimum postoperative follow-up of 2 years.

PATIENT SAMPLE

A total of 113 patients met the generally accepted clinical criteria for chronic lumbar discogenic pain and were selected for the procedure.

OUTCOME MEASURES

Two outcome measures were used for clinical assessment: a surgeon-based modified MacNab method and a patient-based questionnaire. A mandatory poor result was given to any patient who had repeat spine surgery at the same level or has indicated dissatisfaction with the surgical result on the questionnaire response.

METHOD

After meeting CLDP selection criteria, provocation contrast/indigo carmine dye discography was performed. This test was used to confirm the suspected discs as pain generators. The subject surgery then followed. Only cases with one and two levels of confirmed painful discs were entered into the study. The nonoperating author (PMT) analyzed the data.

RESULTS

Using the surgeon assessment method, 17 patients (15%) had excellent results, 32 patients (28.3%) had good results, 34 patients (30.1%) had fair results and 30 patients (26.5%) had poor results. Of the 30 patients in the poor result group, 12 reported either no improvement or worsening, and refused further surgical treatment. Of the remaining 18 patients in the poor group, 8 had spinal fusion, 3 had laminectomy and 7 had repeat spinal endoscopic surgery. The patient-based questionnaire yielded similar percentages in each category. However, only 73.5% of the 113 patients returned the survey questionnaire. There were no aborted procedures, unexpected hemorrhage, device-related complications, neurologic deficits, perioperative deaths or late instability.

CONCLUSIONS

Posterolateral transforaminal SED and radiofrequency thermal annuloplasty were used to interrupt the purported annular defect pain sensitization process, thought to be necessary in the genesis of chronic lumbar discogenic pain. Lack of clinical benefit from the subject procedure did not degrade any subsequent surgical or nonsurgical treatment options. The experience gained from this study warrants further investigation into the cellular and molecular processes that provided back pain relief in these patients.