Minimally invasive approach to far lateral lumbar disc herniation: technique and clinical results

Minimally invasive far lateral tubular microdiscectomy: surgical technique and case series of 176 patients

BACKGROUND

Far lateral (extraforaminal) disc herniations comprise approximately 10% of symptomatic lumbar disc herniations. They represent operative challenges due to accessibility and surgical unfamiliarity. Surgical strategies in the past have included open discectomy and posterior lumbar interbody fusion. Tubular microdiscectomies have gained traction due to their minimally invasive advantages, including reduced morbidity, pain and length of hospital stay.

METHODS

We report our retrospective single institution consecutive case series of tubular far lateral microdiscectomies. One hundred and seventy-six patients were operated on over an eight-year period. Clinical outcomes were assessed after institutional ethics approval. We additionally describe our surgical technique with an illustrative video case.

RESULTS

Over a mean follow-up of 21 weeks, 77% of patients had good or excellent clinical outcomes according to the MacNab criteria. 12% of patients underwent reoperation at the index level for symptom recurrence or persistence. Mean length of hospital stay was 1.3 days. There was a 1% rate of both postoperative haematoma and infection. Mean operation duration was 86 minutes.

CONCLUSION

This case series represents the largest currently reported in the literature. Minimally invasive microdiscectomies performed through tubes allow for precise localisation, reduced tissue disruption and favourable clinical outcomes. Our results appear consistent with a review of the literature, demonstrating the safety and efficacy of this approach.

Unveiling Timetable for Physical Therapy after Single-Level Lumbar Surgery for Degenerative Disc Disease: Insights from a Systematic Review and Meta-Analysis

Background: Postoperative physical therapy emerges as a pivotal element of the rehabilitation process, aimed at enhancing functional recovery, managing pain, and mitigating the risk of further complications. The debate concerning the optimal timing of physical therapy intervention post-surgery remains unresolved; in particular, whether to initiate physical therapy immediately or to wait weeks is of particular interest. The aim of this study is to review the available literature regarding the optimal timing of physical therapy initiation and the outcomes obtained. Methods: This review was carried out in accordance with the Preferential Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. This search was carried out in February 2024. Only peer-reviewed articles were considered for inclusion. Results: Fourteen studies were included. The primary outcomes assessed in the included studies were the following: 12-week and 12-month low back pain, return to work, function and disability, psychological status, patient satisfaction, and complications associated with early physical therapy. A meta-analysis was performed concerning low back pain after lumbar discectomy at 12 weeks and 12 months and complications after early physical therapy after lumbar discectomy and lumbar interbody fusion. A significant difference was found between early and standard physical therapy in terms of low back pain at 12-18 months (p = 0.0062); no significant differences were found in terms of complications, both for discectomy and arthrodesis. Conclusions: This review indicates that employing early rehabilitation strategies for intervertebral disc disease could enhance results in terms of pain and disability without an enhanced risk of complications.

Minimally Invasive Far Lateral Lumbar Discectomy With Modified Technique: Symptomatic Relief and Intersegmental Stability Study

OBJECTIVE

To evaluate the use of a modified minimally invasive surgery (MIS) technique for far lateral lumbar discectomy (FLDH) that minimizes the degree of bony drilling required for nerve root decompression, increasing postoperative pain reduction rate with reduced risk of iatrogenic spinal instability.

SUMMARY OF BACKGROUND DATA

FLDH accounts for approximately 10% of all lumbar disc herniations and is increasingly recognized in the era of advanced imaging techniques. These disc herniations typically result in extra-foraminal nerve root compression. Minimally invasive spine techniques are increasingly performed with various degrees of foraminal and facet removal to decompress the affected nerve root.

METHODS

The study design involves a single institutional, retrospective cohort technical review. The review was completed of all patients undergoing MIS far lateral lumbar discectomy between 2010 and 2020. Cross-sectional, summary statistics were calculated for all variables. Counts and percentages were recorded for categorical variables and mean and standard deviations were calculated for continuous variables.

RESULTS

A total of 48 patients underwent MIS far lateral lumbar discectomies (FLLD) from 2010 to 2020. The mean age was 63 ± 11.5 years (60.4% males), the mean BMI was 28.5 ± 5.5, and 20.8% smokers. The most common presenting complaint was both low back and radicular pain (79.2%) with 8.3% of patients suffering from motor weakness preoperatively. The mean follow-up time was 4.3 ± 2.7. The mean length of stay was 1.3 ± 1.4 days with 77.1% of patients discharged postoperative day one. Forty-three patients (93.5%) had improvement in their symptoms. Twenty-seven (58.7%) had complete resolution in 2.6 months on average. Six patients (13%) had immediate symptom resolution postoperatively.

CONCLUSIONS

Our modified technique for FLLD allows MIS access to the extra-foraminal site of nerve root compression without the need for bony drilling. This minimizes postoperative pain and reduces the risk of iatrogenic spinal instability without sacrificing symptom resolution.

Long-term follow-up results of surgically treated patients with foraminal and far lateral disc herniations

PURPOSE

Foraminal and far lateral disc herniations are rarer cause of nerve root compression. There are reports regarding the outcome, however long-term follow-up results of surgically treated patients are few. The purpose of this retrospective study is to analyze the clinical characteristics and long-term surgical outcomes of the foraminal and far lateral disc herniations.

MATERIALS AND METHODS

The 114 patients who underwent an operation for foraminal and far lateral disc herniaitions were reviewed. Visual analogue scale of back and leg pain, the ocurrence of motor deficit and sensory dysesthesia before and after operations were used to compare the results of early and long-term outcome.

RESULTS

A total of 114 telephone interviews were conducted. The mean follow up was 134 months. Complete relief of symptoms were reported by 77 patients (67.1%). The average VAS of radicular leg pain was 7.5 Post-operatively the average VAS of radicular pain decreased to 2.2. Preoperatively, 9 patients (7.6%) had motor deficit and 17 (14.4%) patients had sensory dysesthesia. Post-operatively 9 (100%) of the patients showed motor, and 12 (70.6%) of the patients showed sensory improvement. In 17 patients with hypoesthesia the complaints continued during 2 weeks to 6 months. They were given gabapentin as medical treatment, however 5 of these patients still have sensory dysesthesia. The outcome was: 67.1% excellent (77 patients), 26.3% good (30 patients), 6.1% fair (7 patients).

CONCLUSION

The far lateral approach is a minimally invasive and safe procedure with low complication rates.

Surgical Treatment of Far Lateral Lumbar Disc Herniation: Outcomes of the Safe and Simple Midline Approach

Objective

Surgery for far lateral lumbar disc herniation (FLLDH) hernias is different than surgery for median and paramedian disc hernias. Our study offers a minimally invasive surgical technic for far lateral disc herniations.

Methods

The results of the midline surgical approach in 18 patients diagnosed with FLLDH were evaluated retrospectively.

Results

A total of 18 patients (7 females, 11 males), with a mean age of 57.9±9.4 years (range: 35-71 years), were included in the analyses. Three patients (16.7%) had lesions at the left L3-L4 level, six patients (33.3%) on the left L4-L5 level, five patients (27.8%) on the right L3-L4 level, and four patients (22.2%) on the right L4-L5 level. All patients had low back and leg pain. These complaints completely regressed after surgery.

Conclusion

This study presents a review of a consecutive series of patients who underwent minimally invasive surgery for FLLDH using a midline approach.

Lumbar Giant Disk Herniations Treated With a Unilateral Approach for Bilateral Decompression

BACKGROUND

Disk herniations that obstruct the spinal canal by more than 50% are named "giant disk herniations" (GDHs). GDHs are challenging to treat from a surgical perspective because of their size and the risk of iatrogenic manipulation during resection resulting in additional neurological compromise. As a result, the appropriateness of minimally invasive tubular approaches for the treatment of lumbar GDHs remains controversial.

OBJECTIVE

To report our experience in treating lumbar GDHs using tubular minimally invasive surgery.

METHODS

A total number of 228 disk herniations were evaluated for the criteria of GDH. In addition, the presence of neurological deficits such as cauda equina syndrome, pain as measured by a visual analog scale, operating time, complications, estimated intraoperative blood loss, and number of surgical revisions were assessed. The standard tubular diskectomy technique was modified to include unilateral laminectomy for bilateral decompression before the diskectomy to create a sufficient working space for removal of the disk fragments.

RESULTS

Twenty-three (10%) patients met the criteria for GDH. Clinically significant motor weakness was present in 21 patients (91.3%) before surgery, and 3 patients (13%) presented with cauda equina syndrome. The average mean visual analog scale (±SD) for the preoperative pain score was 8.3 and decreased to 2.4 at follow-up after surgery. All cases of cauda equina syndrome resolved postoperatively.

CONCLUSION

Unilateral tubular minimally invasive surgery diskectomy seems to be a safe and effective treatment alternative for lumbar GDHs, combined with the "over-the-top" decompression, which provides bilateral decompression and working space.

Abdominal wall pseudohernia - One secondary to a thoracic extraforaminal disc herniation and other due to thoracic paracentral disc protrusion

An abdominal wall pseudohernia is a rare clinical entity which consists of an abnormal bulging of the abdominal wall that can resemble a true hernia, but without an associated underlying fascial or muscle defect. It is caused by segmental neuropathy and subsequent denervation of abdominal wall musculature. We present two cases of an abdominal wall pseudohernia. One secondary to a thoracic extraforaminal disc herniation in a 57-year-old male, which, as far as the authors are aware, has not been described previously. The other in a 67 year old male due to right foraminal and paracentral disc protrusion at T9/10.

A Modified Approach for Minimally Invasive Tubular Microdiscectomy for Far Lateral Disc Herniations: Docking at the Caudal Level Transverse Process

Background and Objectives: The use of minimally invasive retractor systems has significantly decreased the amount of tissue dissection and blood loss, and the duration of post-operative recovery after far-lateral disc herniations (FLDH). In this technical note, the technique of docking the tubular retractor on the caudal transverse process is described for an efficient approach with a decreased need for manipulation of the exiting nerve root. Materials and Methods: The case reported is that of a woman affected by a right-sided FLDH at the L4–5 level causing an L4 radiculopathy with weakness and numbness. A review of the literature for FLDH regarding the key anatomy used during a far lateral approach was also performed. Results: The patient showed a significant improvement of her dorsiflexion weakness and radiating leg pain at her 2-week and 5-week post-operative visits, and at a 6-month follow-up she had near-complete relief of her symptoms, including resolution of foot numbness. Prior techniques for tubular microdiscectomy for FLDH report docking on the facet joint, pars interarticularis, and the cranial transverse process. Conclusions: This technical note details that the utility of docking a tubular retractor at the caudal transverse process improves upon already established techniques for minimally invasive tubular discectomy for FLDH.

Comparing Ipsilateral and Contralateral Laminotomy with Bilateral Decompression in Cases with Far Lateral Disk Herniation and Lumbar Spinal Stenosis

Introduction The aim of this study was to compare clinical results of bilateral decompression and laminotomy and contralateral laminotomy following discectomy from the same side in patients who have far lateral disk herniation and lumbar spinal stenosis at the same level.

Materials and Methods Twenty-four patients with far lateral disk herniation have been divided into two groups: group 1 (n = 14), those who have been through bilateral canal decompression with far lateral discectomy and ipsilateral approach, and group 2 (n = 10), those who have been through far lateral discectomy and bilateral decompression with unilateral approach from contralateral side. Early postoperative, 1st month, and 12th month back and leg pain Visual Analogue Scale (VAS) scores of the patients have been retrospectively evaluated.

Results There is no significant difference between 1st month back and leg pain VAS scores of the groups. But 12th month back and leg pain VAS scores of group 1 are significantly higher than 1st month VAS scores. Also, 12th month back and leg pain VAS scores of group 1 are significantly higher than group 1. In the scanning carried out when the complaints of eight patients in group 1 continued, pars interarticularis fracture has been observed on the side where the surgery has been performed (57.1%). Six of these eight patients have been through stabilization surgery (42.8%).

Conclusion Long-term postoperative results are better in cases who have been performed bilateral decompression with unilateral approach from contralateral side with median incision following paramedian incision discectomy in patients with far lateral disk herniation and spinal stenosis.

Minimally Invasive Far-Lateral Microdiscectomy: A New Retractor for Far-Lateral Lumbar Disc Surgery

Background

To date, a number of approaches have been described for far-lateral disc surgery, including midline, paramedian, and intertransverse approaches. These approaches pose challenges for surgeons due to the difficulty in retraction caused by the anatomy of the foramen. We designed a retractor suitable for the three-dimensional anatomical structure of the foramen. In this study, we aimed to evaluate the surgical outcomes of the patients who were operated on using this retractor in our clinic.

Methods 

The retrospective study included patients who were operated on due to far-lateral disc herniation using the retractor designed in our clinic between February 2013 and December 2018.

Results 

The study included 11 (64.7%) women and 6 (35.3%) men, with a mean age of 56 years (range: 42-70 years). The mean operative time was 49 minutes (range: 40-70 minutes), the mean estimated blood loss was 42 mL (range: 25-60 mL), and the mean follow-up period was 22.6 months (range: 13-48 months). No complication occurred in any patient. A minimally invasive discectomy was performed via the paramedian approach in each patient. The patients were evaluated using the visual analog scale (VAS) for radicular pain, Oswestry Disability Index (ODI), 36-Item Short Form Survey (SF-36), and the modified MacNab criteria.

Conclusion 

The retractor developed in our study provided numerous benefits during the surgical procedure as it led to minimal blood loss and reduced operative times by avoiding bone resection in extraforaminal discs and requiring minimal bone resection in foraminal discs.

Posterolateral Endoscopic Lumbar Decompression Rotate-to-Retract Technique for Foraminal Disc Herniation: A Technical Report

Background and Study Aim

Foraminal disc herniations present the unique surgical challenge for exiting nerve root retraction and decompression. The aim of current study is to describe an innovative maneuver and evaluate its usefulness for endoscopic decompression of foraminal disc herniations.

Material and Methods

A retrospective review was performed including cases of foraminal disc herniations who underwent endoscopic discectomy utilizing the rotate-to-retract technique. Data on patient demographics and improvement in VAS/ODI scores were collected and analyzed statistically.

Results

There were ten patients (three male; seven female) in the final analysis. Seven procedures were done at the L4-L5 level, two were done at the L5-S1 level, and one was done at the L3-L4 level. The average VAS scores improved from preoperatively 7.5 to postoperatively 4.4 (p= 0.001). The mean preoperative ODI was 67.8 and improved to 26.6 postoperatively (p< 0.001). None of the cases reported any neurological or dural complication.

Conclusion

Foraminal disc herniations can be safely and adequately addressed endoscopically with the use of rotate-to-retract technique.

Clinical Outcome of Minimally Invasive Decompression Without Discectomy in Contained Foraminal Disc Herniation: A Single-Center Study

BACKGROUND

Foraminal disc herniation is rare. When conservative treatment fails, it is often treated with discectomy via a paraspinal or Wiltse approach. In contained foraminal disc herniation, more symptoms arise from the foraminal compression of the exiting nerve root, including the dorsal root ganglion, than from the herniation itself. We aimed to evaluate the benefits of stand-alone decompression without discectomy for patients with contained foraminal disc herniation.

METHODS

This study included 17 patients with unilateral single-level foraminal disc herniation (14 women and 3 men; mean age, 62.8 ± 14.6 years, range, 37-86 years). Disc herniation was confirmed as contained by preoperative magnetic resonance imaging and/or computed tomography and by intraoperative exploration. All patients underwent thorough decompression without discectomy, via a paraspinal approach. Pain was evaluated preoperatively and at 3 and 12 months postoperatively using a visual analog scale (VAS). The Oswestry Disability Index (ODI) and Macnab criteria were used to evaluate final outcomes.

RESULTS

The most commonly affected level was L5-S1. All 17 patients showed significant improvements in VAS and ODI scores at 3 and 12 months postoperatively. According to the Macnab criteria, outcome results were excellent in 13 patients and good in 4. The mean duration of follow-up was 18.4 ± 2.4 months, with no recurrences or lumbar instability at the final follow-up.

CONCLUSIONS

Stand-alone decompression without discectomy is an effective method for relieving symptoms and preserving the disc in contained foraminal disc herniation. A minimally invasive approach with thorough decompression techniques yields good results.

A Comparison of the Quality of Sleep between Pre and Post-Surgery Cervical Herniated Nucleus Pulposus Patients Utilizing the Anterior Discectomy Method

BACKGROUND

Herniated Nucleus Pulposus (HNP) is the prolapse of the intervertebral disk through a tear in the annulus fibrosus. This causes nerve root compression with clinical pain manifestation and affects the quality of sleep.

AIM

The aim of this study was find out the comparison in the quality of sleep between before (pre) and after (post) surgery cervical HNP patients.

METHODS

This study was a retrospective cohort study. Ninety patients were asked to complete the Pittsburgh Sleep Quality Index (PSQI) questionnaire. All data which has been computed were analysed with the McNemar test.

RESULT

The outcome reveals that from 90 patient`s cervical HNP, 81 (90%) were 40 years old age group and 66 (73.3%) of them were women. The result showed that 66 (73.3%) patients have a bad sleep quality before surgery. Surgery has increased the quality of sleep after surgery 66 (73.3%) patients had good sleep quality. There was a significant difference in the quality of sleep pre and post operation (p = 0.001).

CONCLUSION

There was a significant difference in the quality of sleep between pre and post operation cervical HNP patient utilising anterior discectomy methods.

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.

Direct Tubular Lumbar Microdiscectomy for Far Lateral Disc Herniation: A Modified Approach

OBJECTIVE

The concept of minimally invasive tubular discectomy is based on precise placement of the retractor over the surgical target to minimize collateral tissue trauma. For far lateral disc herniation, the junction between the pars and the transverse process has generally been adopted as the target for facilitating early nerve root exposure; however, this may limit access to the disc space and increase the risks of iatrogenic neuralgia. An alternative approach to help address these issues involving docking the retractor caudally directly over the disc space with the aid of a microscope is here proposed. The purpose of this study was to evaluate the safety and efficacy of such an approach.

METHODS

Nineteen patients in whom the modified approach was performed over a 35-month period were identified. Direct access to the disc space was attained by directing the retractor against the lateral margin of the facet joint and following the inferior transverse process medially towards the foramen with minimal exposure of the nerve root. Clinical outcomes were assessed by the Oswestry Disability Index, visual analogue scale scores for leg and back pain, Short Form 36 physical functioning (SF36-PF) and bodily pain (SF36-BP) scores and sciatica bothersomeness and frequency indexes (SBI & SFI) and obtained from a prospective patient database. Follow-up data in the first 6 months were compared with preoperative baseline data.

RESULTS

All procedures were successfully completed with the modified approach. Contained disc herniation without sequestrated fragments was found in all but four cases. No perioperative complications or reoperation were recorded and no postoperative dysesthesia was noted. Clinically significant reductions in mean Oswestry Disability Index (32; 95% CI, 21-43) and visual analogue scale scores for leg pain (38 mm; 95% CI, 23-54 mm) and back pain (35 mm; 95% CI, 21-48 mm) scores were noted in the first 6 months. Significant improvements in SF36-PF (40; 95% CI, 30-51) and SF36-BP (35; 95% CI, 26-43), SBI (9; 95% CI, 6-11) and SFI (11; 95% CI, 8-13) were also recorded.

CONCLUSIONS

A modified direct tubular approach is safe and effective for treating far lateral lumbar disc herniation. Our early results suggest that this approach helps safeguard adequate decompression and reduce the risk of postoperative dysesthesia.

Far lateral microdiscectomy: a minimally-invasive surgical technique for the treatment of far lateral lumbar disc herniation

Lumbar disc herniation arises when the annulus fibrosus of the vertebral disc fails, thus allowing displacement of the nucleus pulposus and other tissue. The term far lateral is used variably in the literature and usually refers to an extraforaminal displacement in the peridiscal zone peripheral to the sagittal plane of the most lateral part of the pedicle at the same level. Non-surgical treatments of far lateral disc herniation include physical therapy, anti-inflammatory medication, and corticosteroid injections. Where these conservative measures fail, surgical intervention may be required. Several surgical techniques for the treatment of far lateral herniations have been investigated, including total or medial facetectomy, laminectomy, hemilaminectomy, approaches through the pars interarticularis, and lateral approaches between the transverse processes via the intertransverse muscle and ligament. We present our far lateral microdiscectomy technique which involves accessing the nerve root lateral to the foramen through a small paramedian incision and use of an operating microscope. Far lateral microdiscectomy offers the prospect of better long-term results than other surgical techniques because of less extensive muscle dissection and preservation of the integrity of the facet joint.

Clinical and Radiological Characteristics of Lumbosacral Lateral Disc Herniation in Comparison With Those of Medial Disc Herniation

Lateral disc herniation (foraminal and extra foraminal) has clinical characteristics that are different from those of medial disc herniation (central and subarticular), including older age, more frequent radicular pain, and neurologic deficits. This is supposedly because lateral disc herniation mechanically irritates or compresses the exiting nerve root or dorsal root ganglion inside of a narrow canal more directly than medial disc herniation. The purpose of this study was to investigate clinical and radiological characteristics of lateral disc herniation in comparison with medial disc herniation. The 352 subjects diagnosed with localized lumbosacral disc herniation and followed up for at least 12 months after completion of treatment were included and divided into medial and lateral disc herniation groups, according to the anatomical location of the herniated disc in axial plain of magnetic resonance image. Clinical and radiological data were obtained and compared between the two groups. The lateral group included 74 (21%) patients and the medial group included 278 (79%). Mean age of the lateral group was significantly higher than that in the medial group. The lateral group showed a significantly larger proportion of patients with radiating leg pain and multiple levels of disc herniations than the medial group. No significant differences were found in terms of gender, duration of pain, pretreatment numeric rating scale, severity of disc herniation (protrusion and extrusion), and presence of weakness in leg muscles. The proportion of patients who underwent surgery was not significantly different between the 2 groups. However, the proportion of patients who accomplished successful pain reduction after treatment was significantly smaller in the lateral than in the medial group. In conclusion, patients with lateral disc herniation were older and had larger proportion of radiating leg pain than those with medial disc herniation. Lateral disc herniation was more associated with multiple disc herniations and worse clinical outcomes after treatment than medial disc herniation.

Incidence of Low Back Pain After Lumbar Discectomy for Herniated Disc and Its Effect on Patient-reported Outcomes

BACKGROUND

Long-term postdiscectomy degenerative disc disease and low back pain is a well-recognized disorder; however, its patient-centered characterization and quantification are lacking.

QUESTIONS/PURPOSES

We performed a systematic literature review and prospective longitudinal study to determine the frequency of recurrent back pain after discectomy and quantify its effect on patient-reported outcomes (PROs).

METHODS

A MEDLINE search was performed to identify studies reporting on the frequency of recurrent back pain, same-level recurrent disc herniation, and reoperation after primary lumbar discectomy. After excluding studies that did not report the percentage of patients with persistent back or leg pain more than 6 months after discectomy or did not report the rate of same level recurrent herniation, 90 studies, which in aggregate had evaluated 21,180 patients, were included in the systematic review portion of this study. For the longitudinal study, all patients undergoing primary lumbar discectomy between October 2010 and March 2013 were enrolled into our prospective spine registry. One hundred fifteen patients were more than 12 months out from surgery, 103 (90%) of whom were available for 1-year outcomes assessment. PROs were prospectively assessed at baseline, 3 months, 1 year, and 2 years. The threshold of deterioration used to classify recurrent back pain was the minimum clinically important difference in back pain (Numeric Rating Scale Back Pain [NRS-BP]) or Disability (Oswestry Disability Index [ODI]), which were 2.5 of 10 points and 20 of 100 points, respectively.

RESULTS SYSTEMATIC REVIEW

The proportion of patients reporting short-term (6-24 months) and long-term (> 24 months) recurrent back pain ranged from 3% to 34% and 5% to 36%, respectively. The 2-year incidence of recurrent disc herniation ranged from 0% to 23% and the frequency of reoperation ranged from 0% to 13%.

PROSPECTIVE STUDY

At 1-year and 2-year followup, 22% and 26% patients reported worsening of low back pain (NRS: 5.3 ± 2.5 versus 2.7 ± 2.8, p < 0.001) or disability (ODI%: 32 ± 18 versus 21 ± 18, p < 0.001) compared with 3 months.

CONCLUSIONS

In a systematic literature review and prospective outcomes study, the frequency of same-level disc herniation requiring reoperation was 6%. Two-year recurrent low back pain may occur in 15% to 25% of patients depending on the level of recurrent pain considered clinically important, and this leads to worse PROs at 1 and 2 years postoperatively.

Transforaminal percutaneous endoscopic surgery for far lateral lumbar intervertebral disk herniation

Far lateral lumbar intervertebral disk herniation (FLLIDH) most commonly occurs far lateral to the intervertebral facet at L3-L4 and L4-L5 and accounts for 3.8% of all lumbar disk herniations. Traditional surgery for FLLIDH involves massive surgical trauma, damage to the spinal structure, and instability of the lumbar spine. The goals of this study were to perform a systematic review of the literature and investigate the clinical outcomes of transforaminal percutaneous endoscopic surgery in the treatment of FLLIDH. Between October 2010 and May 2012, fifteen patients diagnosed with FLLIDH underwent transforaminal percutaneous endoscopic surgery at the authors' institution to remove the herniated disk and release the nerve root. Pain was measured pre- and postoperatively with a visual analog pain scale (VAS), and postoperative outcomes were evaluated using MacNab's criteria. A PubMed database search was conducted for the systematic review. Median operative time was 100 minutes (range, 80-140 minutes). Median volume of intraoperative blood loss was 20 mL (range, 10-50 mL). Patients were followed postoperatively for a median of 6 months (range, 1-12 months). MacNab's criteria rated 12 (80.0%) surgical outcomes as excellent, 2 (13.3%) as good, and 1 (6.7%) as fair. The systematic review included 14 studies. Transforaminal percutaneous endoscopic surgery appears to be a safe and effective minimally invasive procedure for treating FLLIDH. However, as demand for this type of surgery increases, the possibility of intraoperative aggravated leg pain and compression injury of the ganglion must be considered.

Extraforaminal compression of the L-5 nerve root at the lumbosacral junction: clinical analysis, decompression technique, and outcome

OBJECT

Extraforaminal compression of the L-5 nerve encompasses multiple pathological entities and may result from disc herniations as well as bony (osteophytes or sacral ala) or ligamentous (sacroiliac ligament and lumbosacral band) compression. Several other factors, such as disc space collapse or coronal wedging, can also contribute to narrowing of the extraforaminal space. The extraforaminal space at L5-S1 has unique anatomical features compared with the upper lumbar levels, which makes surgical access to this region difficult. Minimally invasive techniques offer easier access to the region. The purpose of this study was to analyze the contributing factors for extraforaminal compression of the L-5 nerve and assess clinical outcome following surgical decompression.

METHODS

Fifty-two consecutive patients who underwent a minimally invasive far-lateral approach for extraforaminal compression of the L-5 nerve were retrospectively analyzed for clinical data, outcomes, and imaging features (type of disc prolapse, coronal wedging, degree of disc and facet degeneration, facet tropism, foraminal stenosis, osteophytes, and adjacent-level disease). The authors describe the surgical technique used in this study.

RESULTS

The mean age of the patient sample was 57 years. Sixteen patients each had an extraforaminal ruptured disc or contained protrusion, and the remaining 20 patients had disc protrusions extending into the foraminal region or the lateral recess. Associated foraminal stenosis was found in 38.5%, and adjacent-level stenosis was noted in 22 cases (42.3%) and spondylolisthesis in 4 (7.7%). Osteophytes were noted in 18 cases. A coronal wedging angle ≥ 3° was found in 46.2%, and the laterality of wedging corresponded to the symptomatic side in 91% of cases. Fifteen patients (28.8%) complained of postoperative dysesthesias, which completely resolved in all cases within 6 months. The incidence of dysesthesias was more common in the ruptured disc group. There were no differences in clinical outcome among the different types of disc prolapses. The mean preoperative and postoperative visual analog scale scores were 7.6 and 3.6, respectively. The mean preoperative and postoperative Japanese Orthopaedic Association (JOA) scores were 6.4 and 13.8, respectively. The mean JOA recovery rate was 86.1%. According to the Macnab functional grading system, 96% of the patients had excellent or good grades at follow-up.

CONCLUSIONS

A minimally invasive far-lateral approach to L5-S1 requires a good understanding of the regional anatomy and can provide good to excellent clinical results in properly selected cases. This approach is effective in decompressing the far-lateral and foraminal zones. Adequate preoperative diagnosis and tailoring the surgical procedure to address the relevant compressive element in each case is essential to achieving good clinical results.

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.

Ultra-long-term outcome of surgically treated far-lateral, extraforaminal lumbar disc herniations: a single-center series

PURPOSE

Far-lateral extraforaminal lumbar disc herniation is an uncommon cause of nerve root entrapment, and studies addressing the long-term outcome of surgically treated patients are few. The purpose of this study was to analyze the ultra-long-term outcome of patients who were treated via a lateral approach.

METHODS

The medical reports of 138 consecutive patients were analyzed with regard to signs and symptoms, operative findings, complications, and short-term outcome (6 weeks). To assess long-term results, standardized telephone interviews were performed using a structured questionnaire. The patients were questioned about pain using the verbal rating scale and persisting symptoms, if any. Other queries were related to the Oswestry Disability Index. Subjective satisfaction with the result of surgery was classified as excellent (no pain), good (some pain), fair (moderate pain), and poor (unchanged or worse) based on MacNab classification.

RESULTS

At short-term follow-up, major and moderate leg pain had decreased from 99.3 to 5.1% and low back pain from 97.8 to 2.8%. Sensory and motor deficits, however, were still present in the majority of patients. A total of 87 telephone interviews were conducted, and the mean follow-up was 146 months. As many as 49 patients (56.3%) reported complete relief of symptoms, 14 patients (16.1%) had minor ailments under physical stress, and 24 patients (27.6%) had permanent residual symptoms. The most common complaint was remaining sensory disturbance. Despite residual symptoms, the vast majority of patients expressed satisfaction with the result of surgery. The outcome was subjectively rated as follows: 75.9% excellent (66 patients), 18.4% good (16 patients), 4.6% fair (4 patients), and 1.1% poor (1 patient).

CONCLUSIONS

The lateral approach is a minimally invasive and safe procedure with low complication rates. The profit from surgery is maintained beyond the usual postoperative observation periods. Thus, ultimate outcome at ultra-long-term follow-up is very gratifying in the vast majority of patients.