A minimally invasive technique for L5–S1 intraforaminal disc herniations: microdiscectomy with a tubular retractor via a contralateral approach

Unilateral Biportal Endoscopic Discectomy via the Contralateral Approach in Upward Migrated Foraminal Disc Herniations

OBJECTIVE

Lumbar upward migrated foraminal disc herniations are extremely rare and technically challenging to operate. In this study, a contralateral approach using unilateral biportal endoscopy, which has the advantages of structural protection, efficacy, and safety is presented.

METHODS

Between 2019 and December 2022, five patients with lumbar upward migrated foraminal disc herniations underwent unilateral biportal endoscopic discectomy via the contralateral approach. The patients were 4 males and 1 female patient. All patients had severe radicular pain. Neurological examination revealed sensory impairment and motor weakness in 2 patients but no deficits in the others. Magnetic resonance images confirmed lumbar upward migrated foraminal disc herniations in all patients.

RESULTS

The study shows a significant reduction in Oswestry Disability Index. Symptoms improved immediately after surgery in all patients, and satisfactory results were achieved at the last follow-up. No surgical complications or recurrent herniations were observed. The mean preoperative Oswestry Disability Index decreased from 44.6 to 11.4. In addition, mean preoperative Visual Analog Scale declined from 8.4 to 1.6. The patients were assessed after a follow-up period of at least 22 months, and their level of pain level was documented.

CONCLUSIONS

Although unilateral biportal endoscopic discectomy via the contralateral approach is not a common surgical procedure, it can offer a viable alternative for patients with lumbar upward migrated foraminal disc herniations.

Safety and Utility of Bilateral-contralateral Decompression for Adjacent Segment Stenosis After Lumbar Interbody Fusion Using Unilateral Biportal Endoscopy

STUDY DESIGN

Retrospective case series study.

OBJECTIVE

To evaluate the safety and efficacy of bilateral-contralateral decompression using unilateral biportal endoscopy (UBE) for treating adjacent segment disease (ASD) after lumbar interbody fusion (LIF).

SUMMARY OF BACKGROUND DATA

ASD is a well-documented complication following LIF, often requiring additional surgical interventions. Traditional decompression techniques risk damaging the facet joints, potentially leading to further instability and degeneration. However, our bilateral-contralateral decompression using UBE focuses on minimizing facet joint resection and reducing the risk of postoperative instability.

METHODS

This study included 37 patients who underwent bilateral-contralateral UBE decompression for ASD following LIF at the L4-5 level between September 2020 and March 2022. Radiographic evaluations included measurements of vertebral range of motion (ROM), slip distance, disk height, lumbar lordosis, and facet joint preservation. Clinical assessments were performed using the visual analog scale (VAS) for back and leg pain and the Oswestry disability index (ODI).

RESULTS

The average final follow-up period was 14.5±1.9 mo. The average preoperative ROM was 3.0 degrees, which significantly increased to 4.8° at the final follow-up (P<0.05). Static structure and dynamic stability parameters, including the vertebral slip distance, lumbar lordosis, and disk height, showed no significant differences between the preoperative examination and 1-year postoperative follow-up. The facet joint preservation rate was 97.4±2.1% on average. Significant improvements in VAS scores for leg and back pain and ODI were observed. Despite improvement with conservative treatment in 7 patients with delayed instability, 2 patients required fusion surgery.

CONCLUSIONS

Bilateral-contralateral decompression through UBE has proven to be an effective and safe method for treating ASD following LIF. This technique is particularly suitable for patients requiring spinal stability maintenance. The high rates of facet joint preservation and low incidence of reoperation highlight this technique as a compelling alternative treatment for spinal stenosis.

LEVEL OF EVIDENCE

Level III.

Finite element mechanical analysis of ipsilateral approach and contralateral approach in unilateral bilateral endoscopic spine surgery

BACKGROUND

Unilateral bilateral endoscopic spine surgery (UBE) is often performed to treat lumbar spinal stenosis and disc herniation. It has become a prominent method in endoscopic spine surgery because of its very low learning curve and broader operative field of vision. Currently, the ipsilateral approach and contralateral approach have been established for disc herniation in the foraminal area, intervertebral foramen region, or pedicle region. The contralateral method offers many benefits over the ipsilateral approach, including less bone labour during microsurgical decompression and the preservation of facet joints. However, because it uses the interlaminar window approach, it inevitably involves osteotomy of the patient's superior and inferior articular processes, which may result in corresponding deterioration in the spine's biomechanical stability and subsequent adjacent facet joint diseases caused by facet joint degeneration postoperatively.

OBJECTIVE

As a result, the purpose of this work is to use a finite element model to evaluate how the ipsilateral approach and contralateral approach in unilateral bilateral endoscopic spine surgery affect spinal stability while treating identical intervertebral disc herniation.

STUDY DESIGN

In this study, a three-dimensional lumbar-sacral spine model was built and verified. Osteotomies were conducted for armpit-type lumbar disc herniation (LDH), periradicular-type LDH, and shoulder-type LDH. Postoperative lumbar spine models of the ipsilateral approach and contralateral approach in unilateral bilateral endoscopic spine surgery were developed. The von Mises stress on the endplate, shear force on the annulus fibrosus, pressure inside the intervertebral disc, and range of motion (ROM) of the L3 segment were all determined. The results of our well-validated model showed that osteotomy done in the ipsilateral approach deteriorated most biomechanical metrics.

RESULTS

In the majority of loading conditions, the contralateral approach caused the intervertebral disc's biomechanical properties to increase, and the ipsilateral approach caused the intervertebral disc's biomechanical properties to increase sharply more than the contralateral approach.

CONCLUSION

The contralateral approach, which is now extensively employed in unilateral bilateral endoscopic spine surgery, may be regarded as an ideal surgical alternative for treating lumbar disc herniation without producing iatrogenic instability. This approach has a low facet joint reduction rate, minimum soft tissue injury, and precisely identifies the midline of the central spinal canal during the retraction of the thecal sac and nerve roots.

The interlaminar contralateral approach to far-lateral lumbar disc herniations: a single-center comparison with traditional techniques

BACKGROUND

The interlaminar contralateral approach (ICA) is a promising surgical alternative for the treatment of far-lateral lumbar disc herniations (FLLDH). To date no study has compared ICA and FLLDH conventional surgical treatments, namely the intertransverse, the transmuscular and the intermuscular approaches, in terms of safety and outcome.

METHODS

Patients who underwent FLLDH surgery at our Institution between January 2015 and September 2018 were reviewed. ICA complications and clinical outcomes were compared with those of conventional approaches at 1-month postoperatively and at the last follow-up available. Improvement was defined as reduction of at least two point in the Visual Analogue Scale (VAS) or increase of at least 1 point in the Medical Research Council (MRC) scale of muscle strength. Patient-reported outcome was assessed with the Oswestry Disability Index (ODI).

RESULTS

Among 38 patients, 18 underwent ICA and 20 a conventional approach (intertransverse in 16, transmuscular in two, intermuscular in two). Median follow-up was 21 months (range, 2-47). At 1 month, no differences between the two groups were noticed in terms of clinical outcome and symptoms relief (P> 0.05). The median postoperative ODI score was significantly lower in the Conventional approach group at 1 month (P<0.05), but this difference was no longer significant at the last follow-up evaluation (P>0.05). No differences were found between the two groups in surgical complication and recurrence rates.

CONCLUSIONS

Our data suggest that the ICA is a safe and effective alternative to conventional approaches in FLLDH surgery. Larger prospective studies are needed to confirm our results.

The Contralateral Approach to intra- and Extraforaminal Lumbar Disk Herniations: Surgical Technique and Review of Surgical Procedures

BACKGROUND

 Surgery for intra-/extraforaminal disk herniations (IEDH) is technically demanding due to the hidden location of the compressed nerve root section. Ipsilateral approaches (medial and lateral) are accompanied by extended resection of the facet joint and inadequate visualization of the pathology, especially at the L5-S1 level.

METHODS

 We describe a microsurgical interlaminar contralateral approach (MICA) suitable for IEDH at the lumbosacral junction that can also be used at L4-L5 and L3-L4.

CONCLUSION

 The MICA provides access and sufficient intraforaminal visualization for IEDH in the lumbosacral region without resection of stability-relevant structures or manipulation of the nerve root ganglion.

[Degenerative lumbar spine stenosis: minimally invasive microsurgical methods of treatment]

Degenerative lumbar spine stenosis is one of the main causes of chronic pain and radiculopathy in advanced age people. Along with increase in average life expectancy, degenerative lumbar spine stenosis becomes the most common indication for spinal surgery. There is still no consensus regarding the most optimal surgical approach due to the variety of modern surgical methods. In recent years, minimally invasive spinal surgery has become a more advisable alternative to open surgery due to its advanced technical features combined with less soft tissue damage, lower risk of complications and shorter postoperative recovery.

Minimally Invasive Contralateral Over-the-Top Approach for Lumbar Calcified Foraminal Lesions: A Technical Note

BACKGROUND

Various surgical techniques have been described to address intraforaminal/extraforaminal lumbar lesions. They vary from the classic posterior open approaches to minimally invasive techniques with tubular retractors and even endoscopy. These lesions have been approached from either an ipsilateral or a contralateral approach. Only a few reports have described a contralateral minimally invasive tubular approach to address these lesions. However, none of them have been able to address calcified pathologies.

METHOD

We used a contralateral tubular approach to remove the calcified disc herniations in 2 patients presenting with radiculopathy secondary to a calcified intraforaminal L5-S1 disc herniation.

RESULTS

Early clinical and radiological outcomes were positive. No perioperative complications occurred.

CONCLUSIONS

To our knowledge, this is the first report of the expanded use of fixed tubular retractors to address calcified lumbar intraforaminal disc herniations. This approach allows a satisfactory access and view of the contralateral foramen and offending lesion. It permits a wide decompression while preserving the facet joint and thus prevents iatrogenic instability. It can also avoid the iliac crest, which does not allow an ipsilateral extraforaminal approach at the L5-S1 level. This approach is a safe and effective way to treat this specific pathology.

Facet-Sparing Decompression of Lumbar Spinal Stenosis: The Minimally Invasive Bilateral Crossover Approach

BACKGROUND AND STUDY OBJECTIVE

 One risk of established decompression techniques for lumbar spinal stenosis is the resection of facet joints, especially if they are steeply configured, promoting destabilization. Minimally invasive bilateral crossover decompression aims to preserve the facet joints and thus stability of the spine. The purpose of this study is to demonstrate the feasibility and early results of this technique.

METHODS

 This retrospective case series includes 10 consecutive patients with lumbar stenosis and steep-angle (<35 degrees) facet joints who were treated with minimally invasive bilateral crossover decompression. Eleven segments were decompressed, most commonly L3/L4 (63.6%), followed by L1/L2 and L2/L3 (18.2% each). The effectiveness of surgical decompression was assessed by self-reporting questionnaires.

RESULTS

 After a follow-up of 10.5 months, the Symptom Severity Scale and Physical Function Scale of the Swiss Spinal Stenosis Questionnaire improved by 0.9 (p < 0.05) and 0.7 points, respectively. The mean Oswestry Disability Index improved from 53.9 to 34.6 (p < 0.05). Local and radiating pain under strain showed statistically significant improvement on the Visual Analog Scale (8.9 vs. 5.0 and 8.4 vs. 4.6, respectively). Maximum walking distance increased from 190 to 1,029 m. Apart from one patient requiring surgical decompression of an adjacent segment, there were no reoperations, neurological deteriorations, or other complications.

CONCLUSION

 The results of this study indicate that minimally invasive bilateral crossover decompression is a promising technique for the treatment of spinal canal stenosis. With its design to spare facet joints, it can potentially reduce the risk of spinal instability, especially in patients with steep facet joints.

Early Outcomes of Endoscopic Contralateral Foraminal and Lateral Recess Decompression via an Interlaminar Approach in Patients with Unilateral Radiculopathy from Unilateral Foraminal Stenosis

OBJECTIVE

Percutaneous endoscopic contralateral interlaminar lumbar foraminotomy (PECILF) for lumbar degenerative spinal stenosis is an established procedure. Better preservation of contralateral facet joint compared with that of the approach side has been shown with uniportal bilateral decompression. The aim of this retrospective case series was to analyze the early clinical and radiologic outcomes of stand-alone contralateral foraminotomy and lateral recess decompression using PECILF.

METHODS

Twenty-six consecutive patients with unilateral lower limb radiculopathy underwent contralateral foraminotomy and lateral recess decompression using PECILF. Their clinical outcomes were evaluated with visual analog scale leg pain score, Oswestry Disability Index, and the MacNab criteria. Completeness of decompression was documented with a postoperative magnetic resonance imaging.

RESULTS

Mean age for the study group was 62.9 ± 9.2 years and the male/female ratio was 4:9. A total of 30 levels were decompressed, with 18 patients (60%) undergoing decompression at L4-L5, 9 at L5-S1 (30%), 2 at L3-L4 (6.7%), and 1 at L2-L3 (3.3%). Mean estimated blood loss was 27 ± 15 mL per level. Mean operative duration was 48 ± 12 minutes/level. Visual analog scale leg score improved from 7.7 ± 1 to 1.8 ± 0.8 (P < 0.0001). Oswestry Disability Index improved from 64.4 ± 5.8 to 21 ± 4.5 (P < 0.0001). Mean follow-up of the study was 13.7 ± 2.7 months. According to the MacNab criteria, 10 patients (38.5%) had good results, 14 patients (53.8%) had excellent results, and 2 patients (7.7%) had fair results. One patient required revision surgery.

CONCLUSIONS

Facet-preserving contralateral foraminotomy and lateral recess decompression with PECILF is effective for treatment of lateral recess and foraminal stenosis. Thorough decompression with acceptable early clinical outcomes and minimal perioperative morbidity can be obtained with the contralateral endoscopic approach.

Surgical treatment of intraforaminal/extraforaminal lumbar disc herniations: Many approaches for few surgical routes

BACKGROUND

Several disc disease nomenclatures and approaches for LDH exist. The traditional midline bone-destructive procedures together with approaches requiring extreme muscular retraction are being replaced by muscle sparing, targeted, stability-preserving surgical routes. The increasing speculation on LDHs and the innovative corridors described to treat them have lead to an extensive production of papers frequently treating the same topic but adopting different terminologies and reporting contradictory results.

METHODS

The review of such literature somehow confounding gave us the chance to regroup by surgical corridors the vast amount of approaches for LDH differently renamed over time. Likewise, LDHs were simplified in intra-foraminal (ILDH), extra-foraminal (ELDH), and intra-/extra-foraminal (IELDH) in relation to precise anatomical boundaries and extent of bulging disc.

RESULTS

Through the analysis of the papers, it was possible to identify ideal surgical corridors for ILDHs, ELDHs, and IELDHs, distinguishing for each approach the exposure provided and the technical advantages/disadvantages in terms of muscle trauma, biomechanical stability, and nerve root preservation. A significant disproportion was noted between studies discussing traditional midline approaches or variants of the posterolateral route and those investigating pros and cons of simple or combined alternative corridors. Although rarely discussed, these latter represent valuable strategies particularly for the challenging IELDHs, thanks to the optimal compromise between herniation exposure and bone-muscle preservation.

CONCLUSIONS

The integration of adequate mastery of traditional approaches together with a greater confidence through unfamiliar surgical corridors can improve the development of combined mini-invasive procedures, which seem promising for future targeted LDH excisions.

Ten-Step Minimally Invasive Spine Lumbar Decompression and Dural Repair Through Tubular Retractors

BACKGROUND: Minimally invasive spine (MIS) surgery utilizing tubular retractors has become an increasingly popular approach for decompression in the lumbar spine. However, a better understanding of appropriate indications, efficacious surgical techniques, limitations, and complication management is required to effectively teach the procedure and to facilitate the learning curve.

OBJECTIVE: To describe our experience and recommendations regarding tubular surgery for lumbar disc herniations, foraminal compression with unilateral radiculopathy, lumbar spinal stenosis, synovial cysts, and dural repair.

METHODS: We reviewed our experience between 2008 and 2014 to develop a step-by-step description of the surgical techniques and complication management, including dural repair through tubes, for the 4 lumbar pathologies of highest frequency. We provide additional supplementary videos for dural tear repair, laminotomy for bilateral decompression, and synovial cyst resection.

RESULTS: Our overview and complementary materials document the key technical details to maximize the success of the 4 MIS surgical techniques. The review of our experience in 331 patients reveals technical feasibility as well as satisfying clinical results, with no postoperative complications associated with cerebrospinal fluid leaks, 1 infection, and 17 instances (5.1%) of delayed fusion.

CONCLUSION: MIS surgery through tubular retractors is a safe and effective alternative to traditional open or microsurgical techniques for the treatment of lumbar degenerative disease. Adherence to strict microsurgical techniques will allow the surgeon to effectively address bilateral pathology while preserving stability and minimizing complications.

Contralateral Approach for Minimally Invasive Treatment of Upper Lumbar Intervertebral Disc Herniation: Technical Note and Case Series

BACKGROUND

Upper lumbar disc herniations comprise only 1%-2% of all lumbar disc herniations. Patients exhibit nonspecific signs and symptoms in comparison to predictable radiculopathies, as seen in lower lumbar disc herniations. The unique anatomic characteristics of the upper lumbar spine present several challenges for safe and effective surgical treatment of disc herniations. The authors review the anatomy of the upper lumbar spine, describe a novel approach to upper lumbar disc herniations, and present 3 cases with a focus on clinical outcome and technical pearls.

METHODS

Conventional techniques for upper lumbar discectomy require a near complete facetectomy and pars interarticularis resection for adequate bony exposure, possibly leading to spinal destabilization. A tubular retractor system was used to approach upper lumbar disc herniation using a contralateral minimally invasive technique, while completely preserving the facet complex and pars interarticularis.

RESULTS

We report 3 cases of minimally invasive discectomy from a contralateral approach. The patients experienced complete resolution of presenting symptoms, and the facet complexes were preserved. All cases were free of complications.

CONCLUSION

A contralateral approach to perform a minimally invasive discectomy for paracentral and central upper LDH is a safe, efficient, and effective technique. The approach that we describe in this study preserves the facet complex and may prevent future spinal instability.

Early experience with endoscopic foraminotomy in patients with moderate degenerative deformity

OBJECTIVE Asymmetrical degeneration of the disc is one of the most common causes of primary degenerative scoliosis in adults. Coronal deformity is usually less symptomatic than a sagittal deformity because there is less expenditure of energy and hence less effort to maintain upright posture. However, nerve root compression at the fractional curve or at the concave side of the main curve can give rise to debilitating radiculopathy. METHODS This study was a retrospective analysis of 16 patients with coronal deformity of between 10° and 20°. All patients underwent endoscopic foraminal decompression surgery. The pre- and postoperative Cobb angle, visual analog scale (VAS), 36-Item Short Form Health Survey (SF-36), and Oswestry Disability Index scores were measured. RESULTS The average age of the patients was 70.0 ± 15.5 years (mean ± SD, range 61-86 years), with a mean followup of 7.5 ± 5.3 months (range 2-14 months). The average coronal deformity was 16.8° ± 4.7° (range 10°-41°). In 8 patients the symptomatic foraminal stenosis was at the level of the fractional curve, and in the remaining patients it was at the concave side of the main curve. One of the patients included in the current cohort had to undergo a repeat operation within 1 week for another disc herniation at the adjacent level. One patient had CSF leakage, which was repaired intraoperatively, and no further complications were noted. On average, preoperative VAS and SF-36 scores showed a tendency for improvement, whereas a dramatic reduction of VAS, by 65% (p = 0.003), was observed in radicular leg pain. CONCLUSIONS Patients with mild to moderate spinal deformity are often compensated and have tolerable levels of back pain. However, unilateral radicular pain resulting from foraminal stenosis can be debilitating. In select cases, an endoscopic discectomy or foraminotomy enables the surgeon to decompress the symptomatic foramen with preservation of essential biomechanical structures, delaying the need for a major deformity correction surgery.

Unilateral tubular approach for bilateral laminotomy: effect on ipsilateral and contralateral buttock and leg pain

PURPOSE

Tubular laminotomy is an effective procedure for treatment of lumbar spinal stenosis (LSS) and lateral recesses stenosis. Most surgeons familiar with the procedure agree that the tubular approach appears to afford a more complete decompression of the contralateral thecal sac and nerve root, as compared to the ipsilateral approach. With this study we sought to answer the question whether this is reflected in clinically significant differences between the ipsilateral and contralateral side pain improvements.

METHODS

In a retrospective case study, patients with LSS and lateral recesses stenosis who started out with VAS scores that were similar on the right and left side were included. All patients underwent a tubular (MIS) "over the top" laminotomy from a unilateral approach and through one incision. Surgeries were performed by a single surgeon in a single center. At the last follow-up, the extent of VAS score improvement on the approach (ipsilateral) side was compared to that of the contralateral side.

RESULTS

Thirty-three patients were included in. At the latest follow-up of 25.8 ± 3.4 months, there were statistically significant improvements in ODI and back VAS scores (p = 0.002 and p < 0.0001, respectively). In addition, buttock VAS scores were significantly improved both on the ipsilateral and the contralateral side (p < 0.001, and p = 0.001, respectively). Similarly, leg VAS scores were improved significantly on both sides (p < 0.001, and p = 0.001, respectively). There were no statistically significant differences between the extent of pain improvement on the ipsilateral and the contralateral side.

CONCLUSIONS

MIS tubular laminotomy through a unilateral approach results in clinically effective bilateral decompression of LSS and lateral recesses, regardless of the approach side.

Extreme lateral interbody fusion for unilateral symptomatic vertical foraminal stenosis

PURPOSE

Asymmetric loss of disc height in adult deformity patients may lead to unilateral vertical foraminal stenosis and radiculopathy. The current study aimed to investigate whether restoration of foraminal height on the symptomatic side using extreme lateral interbody fusion (XLIF) would alleviate unilateral radiculopathy.

METHODS

In a retrospective study, patients with single-level unilateral vertical foraminal stenosis and corresponding radicular pain undergoing XLIF were included. Functional data (visual analog scale (VAS) for buttock, leg and back, as well as Oswestry Disability Index (ODI)) and radiographic measurements (bilateral foraminal height, disc height, segmental coronal Cobb angle and regional lumbar lordosis) were collected preoperatively, postoperatively and at the last follow-up.

RESULTS

Twenty-three patients were included, among whom 61 % had degenerative scoliosis. History of previous surgery at the level of index was present in 43 % of patients. Additional instrumentation was performed in 91 %. The foraminal height on the stenotic side was significantly increased postoperatively (p < 0.001), and remained significantly increased at the last follow-up of 11 ± 3.7 months (p < 0.001). Additionally, VAS buttock and leg on the stenotic side, VAS back and ODI were significantly improved postoperatively and at the last follow-up (p ≤ 0.001 for all parameters). The foraminal height on the stenotic side showed correlation with the VAS leg on the stenotic side, both postoperatively and the last follow-up (r = -0.590; p = 0.013, and r = -0.537; p = 0.022, respectively).

CONCLUSIONS

Single-level XLIF is an effective procedure for treatment of symptomatic unilateral foraminal stenosis leading to radiculopathy. In deformity patients with radicular pain caused by nerve compression at a single level, when not associated with other symptoms attributable to general scoliosis, treatment with single-level XLIF can result in short- and mid-term satisfactory outcome.

Minimally invasive laminectomy for lumbar spinal stenosis in patients with and without preoperative spondylolisthesis: clinical outcome and reoperation rates

OBJECT

Surgical decompression is the intervention of choice for lumbar spinal stenosis (LSS) when nonoperative treatment has failed. Standard open laminectomy is an effective procedure, but minimally invasive laminectomy through tubular retractors is an alternative. The aim of this retrospective case series was to evaluate the clinical and radiographic outcomes of this procedure in patients who underwent LSS and to compare outcomes in patients with and without preoperative spondylolisthesis.

METHODS

Patients with LSS without spondylolisthesis and with stable Grade I spondylolisthesis who had undergone minimally invasive tubular laminectomy between 2004 and 2011 were included in this analysis. Demographic, perioperative, and radiographic data were collected. Clinical outcome was evaluated using the Oswestry Disability Index (ODI) and visual analog scale (VAS) scores, as well as Macnab's criteria.

RESULTS

Among 110 patients, preoperative spondylolisthesis at the level of spinal stenosis was present in 52.5%. At a mean follow-up of 28.8 months, scoring revealed a median improvement of 16% on the ODI, 2.75 on the VAS back, and 3 on the VAS leg, compared with the preoperative baseline (p < 0.0001). The reoperation rate requiring fusion at the same level was 3.5%. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical outcome or reoperation rate.

CONCLUSIONS

Minimally invasive laminectomy is an effective procedure for the treatment of LSS. Reoperation rates for instability are lower than those reported after open laminectomy. Functional improvement is similar in patients with and without preoperative spondylolisthesis. This procedure can be an alternative to open laminectomy. Routine fusion may not be indicated in all patients with LSS and spondylolisthesis.

Minimally Invasive Foraminotomy Through Tubular Retractors via a Contralateral Approach in Patients With Unilateral Radiculopathy

BACKGROUND:

Radiculopathy caused by foraminal nerve root compression is a common pathology in the lumbar spine. Surgical decompression via a conventional open foraminotomy is the treatment of choice when surgery is indicated. Minimally invasive tubular foraminotomy through a contralateral approach is a potentially effective surgical alternative.

OBJECTIVE:

The aim of this retrospective cohort study was to evaluate the efficacy and benefits of this approach for treatment of radiculopathy.

METHODS:

Patients with unilaterally dominant lower extremity radiculopathy, who underwent minimally invasive lumbar foraminotomy through tubular retractors via a contralateral approach between 2010 and 2012, were included. Oswestry Disability Index (ODI) and the Visual Analogue Scale (VAS) for back and leg pain were evaluated preoperatively, postoperatively, and at the latest follow-up. Functional outcome was evaluated by using the MacNab criteria.

RESULTS:

For the total 32 patients, postoperatively there was significant improvement in the ODI (P = .006), VAS back pain (P &lt; .001), and VAS leg pain on the pathology and the approach side (P = .004, P = .021, respectively). At follow-up of 12.3 ± 1.7 months, there was also significant improvement in the ODI (P &lt; .001), VAS back pain (P = .001), and VAS leg pain on the pathology and the approach side (P &lt; .001, P = .001, respectively). The functional outcome was excellent and good in 95.2%. One patient required fusion (3.1%).

CONCLUSION:

A minimally invasive, facet-sparing contralateral approach is an effective technique for treatment of radiculopathy due to foraminal compression. It also allows for decompression of lumbar spinal stenosis and bilateral lateral recess decompression without the need for fusion.

Minimally invasive resection of lumbar synovial cysts from a contralateral approach

Synovial cysts of the lumbar spine result from degeneration of the facet capsule and often mimic symptoms commonly seen with herniated intervertebral discs. In symptomatic patients, the prevalence of synovial cysts may be as high as 10%. Although conservative management is possible, the majority of patients will require resection. Traditional procedures for lumbar synovial cyst resection use an ipsilateral approach requiring partial or complete resection of the ipsilateral facet complex, possibly leading to further destabilization. A contralateral technique using minimally invasive tubular retractors for synovial cyst resection avoids facet disruption. The authors report 2 cases of a minimally invasive synovial cyst resection via a contralateral laminotomy. In both cases, complete resection of the cyst was achieved while sparing the facet joint.

Percutaneous endoscopic treatment of foraminal and extraforaminal disc herniation at the L5-S1 level

BACKGROUND

Microsurgery of foraminal and extraforaminal disc herniation at the L5-S1 level remains a challenge because of the limited access by a high iliac crest, the sacral ala, large transverse processes of L5 and hidden disc fragments lateral to the zygapophyseal joint. Our aim was to present the outcome of percutaneous endoscopic lumbar discectomy (PELD) of these lateral and far lateral disc herniations at the L5-S1 level using the newly described foraminal retreat technique in a group of patients with similar preoperative diagnostic studies.

METHODS

A total of 22 patients, 13 males and 9 females, with foraminal and extraforaminal lumbar disc herniation at the L5-S1 level were treated by applying the PELD between September 2004 and April 2010. The clinical findings and MRI were the main diagnostic methods. Preoperative evaluation was performed with clinical examinations, the Visual Analog Pain Scale (VAS) and Oswestry Low Back Disability Index (ODI).

FINDINGS

According to the Macnab criteria, overall excellent or good outcomes were obtained in 18 patients (81.8 %), fair outcomes in 3 patients (13.6 %) and a poor outcome in 1 patient (4.5 %) at the last follow-up. The mean ODI was 67.3 ± 19.4 preoperatively and 26.7 ± 23.4 postoperatively. Preoperative VAS was 88.6 ± 7.6 and 28.6 ± 22.8 at 2 days, 40.5 ± 22.8 at 3 weeks, 34.3 ± 25.1 at 6-months and 32 at the last follow-up. At follow-up, two patients (9.1 %) had recurrent disc herniations that were corrected with open surgery. At the time of surgery, 16 patients held jobs. Fifteen (15) patients (93.8 %) returned to their original jobs postoperatively; one patient could not return to his original job postoperatively because of a comorbidity.

CONCLUSIONS

Percutaneous endoscopic discectomy using the foraminal retreat technique is an effective treatment method for patients with foraminal and extraforaminal disc herniations at the L5-S1 level on appropriately selected patients.

The efficacy of minimally invasive discectomy compared with open discectomy: a meta-analysis of prospective randomized controlled trials

OBJECT

Advocates of minimally invasive discectomy (MID) have promoted this operation as an alternative to open discectomy (OD), arguing that there may be less injury to the paraspinal muscles, decreased postoperative pain, and a faster recovery time. However, a recently published large randomized controlled trial (RCT) comparing these approaches reported inferior relief of leg pain in patients undergoing MID. The authors conducted a meta-analysis to evaluate complications and improvement in leg pain in patients with radiculopathy enrolled in RCTs comparing OD to MID.

METHODS

The authors performed a literature search using Medline and EMBASE of studies indexed between January 1990 and January 2011. Predetermined RCT eligibility included the usage of tubular retractors during MID, a minimum follow-up duration of 1 year, and quantification of pain with the visual analog scale (VAS). Trials that only evaluated patients with recurrent disc herniation were excluded. Data on operative parameters, complications, and VAS scores of leg pain were extracted by 2 investigators. A meta-analysis was performed assuming random effects to determine the difference in mean change for continuous outcomes and the risk ratio for binary outcomes.

RESULTS

Six trials comprising 837 patients (of whom 388 were randomized to MID and 449 were randomized to OD) were included. The mean operative time was 49 minutes during MID and 44 minutes during OD; this difference was not statistically significant. Incidental durotomies occurred significantly more frequently during MID (5.67% compared with 2.90% for OD; RR 2.05, 95% CI 1.05-3.98). Intraoperative complications (incidental durotomies and nerve root injuries) were also significantly more common in patients undergoing MID (RR 2.01, 95% CI 1.07-3.77). The mean preoperative VAS score for leg pain was 6.9 in patients randomized to MID and 7.2 in those randomized to OD. With long-term follow-up (1-2 years postoperatively), the mean VAS score improved to 1.6 in both the MID and OD cohorts. There was no significant difference in relief of leg pain between the 2 approaches with either short-term follow-up (2-3 months postoperatively, 0.81 points on the VAS, 95% CI -4.71 to 6.32) or long-term follow-up (2.64 on the VAS, 95% CI -2.15 to 7.43). Reoperation for recurrent herniation was more common in patients randomized to the MID group (8.50% compared with 5.35% in patients randomized to the OD group), but this difference was not statistically significant (RR 1.56, 95% CI 0.92-2.66). Total complications did not differ significantly between the operations (RR 1.50, 95% CI 0.97-2.33).

CONCLUSIONS

The current evidence suggests that both OD and MID lead to a substantial and equivalent long-term improvement in leg pain. Adequate decompression, regardless of the operative approach used, may be the primary determinant of pain relief-the major complaint of many patients with radiculopathy. Incidental durotomies occurred significantly more frequently during MID, but total complications did not differ between the techniques.

Contralateral approach for far lateral lumbar disc herniations: a modified technique and outcome analysis of nine patients

STUDY DESIGN

A retrospective analysis of 9 patients who underwent a modified surgical procedure for the treatment of far lateral lumbar disc herniations.

OBJECTIVES

To illustrate a modified technique for approaching the neural foramen from the contralateral side, minimizing muscle retraction and bone/ligament resection, and to analyze clinical results.

SUMMARY OF BACKGROUND DATA

The most commonly used surgical techniques for the removal of far lateral lumbar disc herniations are ipsilateral approaches, that require partial or complete facet resection and/or intertransverse ligament resection, which may result in vertebral instability and/or chronic back pain.

METHODS

Nine patients with intraforaminal or intra/extraforaminal lumbar disc herniation underwent surgery using a modified contralateral approach. There was unilateral muscle retraction and no medial facetectomy nor intertransverse/interspinous ligament resection. Preoperative and postoperative Oswestry functional status evaluation and complications were reviewed and Macnab's postoperative categories were assigned to evaluate the efficacy and safety of the surgery.

RESULTS

No serious complications were noted. The mean preoperative and postoperative Oswestry scores were 44 and 14 respectively (P < 0.01). Overall excellent-to-good results were 100%.

CONCLUSION

This modified contralateral approach offered a wide exposure of intervertebral foramen region and allowed to remove the herniated disc material with minimal resection of osseous and ligamentous structures. Successful results were achieved in all patients treated by this technique.