Pacific Spine and Pain Society (PSPS) Evidence Review of Surgical Treatments for Lumbar Degenerative Spinal Disease: A Narrative Review

INTRODUCTION

Interventional treatment options for the lumbar degenerative spine have undergone a significant amount of innovation over the last decade. As new technologies emerge, along with the surgical specialty expansion, there is no manuscript that utilizes a review of surgical treatments with evidence rankings from multiple specialties, namely, the interventional pain and spine communities. Through the Pacific Spine and Pain Society (PSPS), the purpose of this manuscript is to provide a balanced evidence review of available surgical treatments.

METHODS

The PSPS Research Committee created a working group that performed a comprehensive literature search on available surgical technologies for the treatment of the degenerative spine, utilizing the ranking assessment based on USPSTF (United States Preventative Services Taskforce) and NASS (North American Spine Society) criteria.

RESULTS

The surgical treatments were separated based on disease process, including treatments for degenerative disc disease, spondylolisthesis, and spinal stenosis.

CONCLUSIONS

There is emerging and significant evidence to support multiple approaches to treat the symptomatic lumbar degenerative spine. As new technologies become available, training, education, credentialing, and peer review are essential for optimizing patient safety and successful outcomes.

Minimally invasive tubular microdiscectomy for recurrent lumbar disc herniation: step-by-step technical description with safe scar dissection

INTRODUCTION

Recurrent lumbar disc herniation (RLDH) is one of the most common reasons for re-operation after primary lumbar disc herniation with an incidence ranging from 5 to 23%. Numerous RLDH studies have been conducted; however, no available studies have provided a specific description of the use of the tubular retractor discectomy technique for RLDH emphasizing safe scar dissection. The objective of this study is to describe a detailed step-by-step technique for RLDH.

MATERIAL AND METHODS

A surgical technique reporting on our experience from the year 2013-2021 in 9 patients with RLDH at the same level and same side was included in the study. Clinical outcomes were assessed using the visual analog score (VAS) for leg pain before and three months after surgery.

RESULTS

A significant improvement was observed between the preoperative and postoperative VASs [mean (SD): 9.2 (1) vs. 1.5 (1)] for all patients. We did not report any incidental durotomy, neurological deficits or mortality in this study. One patient had superficial wound infection. The study is limited by small population, short follow-up and not reporting stability or spondylolisthesis.

CONCLUSION

A modified tubular discectomy technique with safe scar dissection is effective for RLDH treatment. Technically, the only scar needed to be dissected is the scar lateral to the exposed normal dura and the scar extended caudally till the level of the superior end plate of the targeted disc space where the scar can be entered ventrally and the disc fragment retrieved. Adherence to the step-by-step procedure described in our study will help surgeons operate with more confidence and minimize complications of recurrent lumbar disc herniation.

Simultaneous Anterior Posterior Approach for Single-Position Lateral Lumbar Interbody Fusion with Robotic Assistance: Technical Guidelines and Early Outcomes

BACKGROUND

Lumbar lateral interbody fusion (LLIF) is traditionally performed in 2 stages: placing the interbody cage in the lateral decubitus position, then placing the percutaneous pedicle screw in the prone position. Performing interbody fusion and posterior fixation simultaneously could improve operative efficiency and clinical outcomes associated with longer operative times. We describe the operative steps and report clinical and radiographic outcomes associated with a simultaneous anterior and posterior approach (SAPA) for LLIF.

METHODS

Patients who underwent SAPA LLIF performed by a single surgeon over 1 year were retrospectively reviewed. Demographic, clinical, and radiographic data were analyzed, an operative guideline was created, and a learning curve was constructed using operative times.

RESULTS

SAPA LLIF was performed in 11 patients. Three patients experienced transient postoperative femoral nerve plexopathy with symptoms of ipsilateral hip flexion weakness and/or anterior thigh numbness; there were no other complications in the cohort. Radiographically, patients achieved significant increases in disc height (8.3 mm vs. 13.5 mm, P = 0.002) and foraminal height (20.2 mm vs. 25.3 mm, P = 0.0001). Patients showed significant improvements in Oswestry Disability Index (52 vs. 27.8, P = 0.002) and Patient-Reported Outcome Measurement Information System Physical Function (32.6 vs. 39, P = 0.048) and Pain Interference (64.9 vs. 59.6, P = 0.001) at 3 months. A downward trend in operative time was observed for 1-level SAPA LLIF.

CONCLUSIONS

SAPA LLIF is a safe approach for LLIF that results in favorable clinical outcomes. This technique can potentially improve operative efficiency further along the course of a surgeon's learning curve.

Percutaneous thoraco-lumbar-sacral pedicle screw placement accuracy results from a multi-center, prospective clinical study using a skin marker-based optical navigation system

STUDY DESIGN

Prospective multi-center study.

OBJECTIVE

The study aimed to evaluate the accuracy of pedicle screw placement using a skin marker-based optical surgical navigation system for minimal invasive thoraco-lumbar-sacral pedicle screw placement.

METHODS

The study was performed in a hybrid Operating Room with a video camera-based navigation system integrated in the imaging hardware. The patient was tracked with non-invasive skin markers while the instrument tracking was via an on-shaft optical marker pattern. The screw placement accuracy assessment was performed by three independent reviewers, using the Gertzbein grading. The screw placement time as well as the staff and patient radiation doses was also measured.

RESULTS

In total, 211 screws in 39 patients were analyzed for screw placement accuracy. Of these 32.7% were in the thoracic region, 59.7% were in the lumbar region, and 7.6% were in the sacral region. An overall accuracy of 98.1% was achieved. No screws were deemed severely misplaced (Gertzbein grading 3). The average time for screw placement was 6 min and 25 secs (± 3 min 33 secs). The average operator radiation dose per subject was 40.3 µSv. The mean patient effective dose (ED) was 11.94 mSv.

CONCLUSION

Skin marker-based ON can be used to achieve very accurate thoracolumbarsacral pedicle screw placements.

Setting for single position surgery: survey from expert spinal surgeons

PURPOSE

To describe a comprehensive setting of the different alternatives for performing a single position fusion surgery based on the opinion of leading surgeons in the field.

METHODS

Between April and May of 2021, a specifically designed two round survey was distributed by mail to a group of leaders in the field of Single Position Surgery (SPS). The questionnaire included a variety of domains which were focused on highlighting tips and recommendations regarding improving the efficiency of the performance of SPS. This includes operation room setting, positioning, use of technology, approach, retractors specific details, intraoperative neuromonitoring and tips for inserting percutaneous pedicle screws in the lateral position. It asked questions focused on Lateral Single Position Surgery (LSPS), Lateral ALIF (LA) and Prone Lateral Surgery (PLS). Strong agreement was defined as an agreement of more than 80% of surgeons for each specific question. The number of surgeries performed in SPS by each surgeon was used as an indirect element to aid in exhibiting the expertise of the surgeons being surveyed.

RESULTS

Twenty-four surgeons completed both rounds of the questionnaire. Moderate or strong agreement was found for more than 50% of the items. A definition for Single Position Surgery and a step-by-step recommendation workflow was built to create a better understanding of surgeons who are starting the learning curve in this technique.

CONCLUSION

A recommendation of the setting for performing single position fusion surgery procedure (LSPS, LA and PLS) was developed based on a survey of leaders in the field.

Feasibility of unilateral hemilaminectomy utilizing a Williams retractor for the resection of intradural-extramedullary spinal neoplasms

BACKGROUND

While open approaches have historically been used in the surgical treatment of intradural-extramedullary spine tumors, minimally-invasive surgical (MIS) techniques are frequently applied to minimize post-operative complications associated with open surgery. Tubular retractor systems in particular have been employed in combination with the unilateral hemilaminectomy (UHL) approach. Here we describe the use of a Williams retractor as a safe and effective minimally-invasive alternative to tubular retractor systems with similar post-operative outcomes.

METHODS

We retrospectively reviewed a cohort of eight patients who underwent unilateral hemilaminectomy using a Williams retractor for the minimally-invasive resection of intradural-extramedullary neoplasms at a large tertiary academic center from 2017 to 2019. Patient demographics, pathologic specimens, radiographic studies, and intraoperative parameters were collected and analyzed.

RESULTS

In our series, gross total resection was achieved in all cases. Average operative time was 158±40minutes, the mean estimated blood loss (EBL) was 44.4±30.4mL, and mean length of stay was three days. All patients reported symptomatic improvement at follow-up as reported by Visual Analog Scale scores.

CONCLUSION

A Williams retractor yields similar outcomes with respect to post-operative pain, operative time, and EBL as it maintains the advantages of the UHL approach in the resection of intradural-extramedullary spine tumors while enhancing feasibility and providing significant cost savings.

Evaluation of open and minimally invasive spinal surgery for the treatment of thoracolumbar metastatic epidural spinal cord compression: a systematic review

BACKGROUND

Metastatic epidural spinal cord compression (MESCC) is a debilitating sequela of cancer that results in pain, disability, and neurologic deficits. Surgical techniques have included open surgical (OS) techniques with anterior and/or posterior decompression and fusion procedures. Further technical evolution has led to minimally invasive spinal (MIS) decompression and fusion. The objective of this study is to compare MIS to OS techniques in the treatment of thoracolumbar MESCC.

METHODS

A review of the literature was performed using PubMed database. Inclusion criteria included patients 18 years or older, thoracolumbar MESCC, and surgeries with instrumented fusion. A total of 451 articles met the inclusion criteria and further analysis narrowed them down to 81 articles. Variables collected included blood loss, length of stay, operative time, pre- and postoperative Frankel grade, and complications.

RESULTS

A total of 5726 papers were collected, with a total of 81 papers meeting final inclusion criteria: 26 papers with MIS technique and 55 with OS. A total of 2267 patients were evaluated. They were split into three surgical subtypes of MIS and OS: posterior decompression and fusion, partial corpectomy, and complete corpectomy. Overall, MIS had lower operative time, blood loss, and complications compared to OS. A timeline analysis showed reduction of complication rates in MIS surgery between papers published over a 28-year period.

CONCLUSION

MESCC carries significant morbidity and mortality. Surgical approaches for palliative treatment should account for this fact. We conclude that MIS techniques offer a viable alternative to traditional OS approaches with lower overall morbidity and complications.

Minimally invasive resection of pediatric osteoid osteomas: A report of two cases

Background:

Spinal osteoid osteomas (OOs) are common benign bone tumors that most frequently affect the posterior elements. They occasionally (e.g., 10% of the time) necessitate surgical resection for intractable pain. Given their small size and posterior positions, many may be amenable to minimally invasive surgical approaches.

Case Description:

We describe two cases of spinal OOs involving patients 11 and 17 years of age with lesions, respectively, at T7 and C4.

Conclusion:

Minimally invasive approaches for resection of small bony spinal OOs are safe and technically achievable approaches.

Strategies for posterior-only minimally invasive surgery in thoracolumbar metastatic epidural spinal cord compression

Background:

Metastatic epidural spinal cord compression (MESCC) is a debilitating sequela of cancer. Here, we evaluated various subtypes of posterior-only minimally invasive spinal (MIS) procedures utilized to address different cancers.

Methods:

Within this retrospective review, we analyzed the treatment of thoracolumbar MESCC treated with three MIS techniques: decompression and fusion (Subgroup A), partial corpectomy (Subgroup B), and full corpectomy (Subgroup C).

Results:

There were 51 patients included in the study; they averaged 58.7 years of age, and 51% were females. Most tumors were in the thoracic spine (51%). The average preoperative Frankel grade was D (62.7%); 69% (35) improved postoperatively. The patients were divided as follows: subgroup A (15 patients = 29.4%), B (19 patients = 37.3%), and C (17 patients = 33.3%). The length of hospitalization was similar (~5.4 days) for all groups. The overall complication rate was 31%, while blood loss was lower in Subgroups A and B versus C.

Conclusion:

Different MIS surgical techniques were utilized in patients with thoracic and/or lumbar MESCC. Interestingly, clinical outcomes were similar between MIS subgroups, in this study, with a trend toward higher complications and greater blood loss associated with those undergoing more aggressive MIS procedures (e.g., full corpectomy and fusion).

Posterior Endoscopic Cervical Decompression: Review and Technical Note

Endoscopic spine surgery for the treatment of degenerative spinal diseases from lumbar to cervical spine has accelerated over the past 2 decades. Posterior endoscopic cervical discectomy (PECD) has been described as a safe, effective, and minimally invasive procedure for cervical radiculopathy or even part of the myelopathy. This procedure also has been validated with comparable outcomes to open and microscopic surgery. Radiculopathy due to foraminal disc herniation or foraminal stenosis should be the optimum indications of this procedure. Intraoperative 3-dimensional navigation can help surgeons to get quick and great quality guidance for endoscopic surgeons. In this review, we will focus on the technical details and evidence-based results of PECD which is a promising procedure for cervical radiculopathy with the advantages of a minimally invasive method.

Minimally Invasive Endoscopic Aspiration of a Spinal Epidural Dermoid Cyst Extending From T10 to the Sacrum: 2-Dimensional Operative Video

Dermoid cysts are space-occupying tumors that can occur anywhere in the neuroaxis. Although categorized as benign lesions, they can compromise normal structures, causing neurological function loss, and have a tendency to recur often requiring repeated surgical resections. We illustrate the case of an extensive epidural dermoid cyst in a 22-yr-old woman who presented with progressive loss of neurological motor function in her lower extremities as well as bowel and bladder incontinence. The tumor extended from T10 to the sacrum, and a conventional operation would have entailed serial laminectomies that would cross the thoracolumbar and lumbosacral junctions, possibly requiring an instrumented fusion. Given the fact that operation would have carried significant morbidity, especially with the high likelihood of symptomatic tumoral recurrence, we consulted with our urology colleagues to find a minimally invasive way of reducing the tumor burden and decompressing the neural elements. The patient was taken to the operating room and a limited open lumbosacral durotomy was performed. A flexible cystoscope was then passed in the epidural space and used to suction the tumor. Postoperative imaging showed adequate resection, and the patient recovered neurological function completely. She had mini-mal recurrence at 3 yr and remained asymptomatic. This technical video note showcases the potential for use of endoscopy for spine tumors that have an amenable consistency, even in highly eloquent areas such as the conus medullaris. It also serves to highlight the benefits of interdisciplinary cooperation when treating complex disease. This case report was written in compliance with our institutional ethical review board. Institutional Review Board (IRB) approval and patient consent was waived in light of the retrospective and deidentified nature of the data presented in accordance with the University of Texas SouthWestern IRB. Patient consent was waived for writing this manuscript in light of the retrospective and deidentified nature of the data presented in accordance with our institutional IRB.

Optimizing biomechanics of anterior column realignment for minimally invasive deformity correction

BACKGROUND CONTEXT

Anterior column realignment (ACR) is a powerful but destabilizing minimally invasive technique for sagittal deformity correction. Optimal biomechanical design of the ACR construct is unknown.

PURPOSE

Evaluate the effect of ACR design on radiographic lordosis, range of motion (ROM) stability, and rod strain (RS) in a cadaveric model.

STUDY DESIGN/SETTING

Cadaveric biomechanical study.

PATIENT SAMPLE

Seven fresh-frozen lumbar spine cadaveric specimens (T12-sacrum) underwent ACR at L3-L4 with a 30° implant.

OUTCOME MEASURES

Primary outcome measure of interest was maximum segmental lordosis measured using lateral radiograph. Secondary outcomes were ROM stability and posterior RS at L3/4.

METHODS

Effect of grade 1 and grade 2 osteotomies with single-screw anterolateral fixation (1XLP) or 2-screw anterolateral fixation (2XLP) on lordosis was determined radiographically. Nondestructive flexibility tests were used to assess ROM and RS at L3-L4 in flexion, extension, lateral bending, and axial rotation. Conditions included (1) intact, (2) pedicle screw fixation and 2 rods (2R), (3) ACR+1XLP with 2R, (4) ACR+2XLP+2R, (5) ACR+1XLP with 4 rods (4R) (+4R), and (6) ACR+2XLP+4R.

RESULTS

Segmental lordosis was similar between ACR+1XLP and ACR+2XLP (p>.28). ACR+1XLP+2R was significantly less stable than all other conditions in flexion, extension, and axial rotation (p<.014); however, adding an extra screw improved stability to levels equal to 4R conditions (p>.36). Adding 4R to ACR+1XLP reduced RS in all directions of loading (p<.048), whereas adding a second screw did not (p>.12). There was no difference in strain between ACR+1XLP+4R and ACR+2XLP+4R (p>.55).

CONCLUSIONS

For maximum stability, ACR constructs should contain either fixation into both vertebral bodies (2XLP) or accessory rods (4R). 2XLP can be used without compromising the maximal achievable lordosis but does not provide the same RS reduction as 4R.

CLINICAL SIGNIFICANCE

ACR is a highly destabilizing technique that is increasingly being used for minimally invasive deformity correction. These biomechanical data will help clinicians optimize ACR construct design.

[Efficacy tubular paraspinal approach and conventional semi-laminar approach in treating lumbar stenosis]

Objective: To analysis of the efficacy of tubular paraspinal approach and conventional semi-laminar approach in treating lumbar stenosis. Methods: Retrospective research of clinical data of 56 lumbar stenosis cases who were operated in neurosurgery department of first center of PLA general hospital from May 2015 to June 2018. Collecting the information of sex, age, operating time, intraoperative blood loss, postoperative duration in bed, as well as length of hospital stay of those patients. The 2 groups of cases, tubular paraspinal approach group (n=35)and semi-laminal approachgroup (n=21), compared by Japanese orthopedic association (JOA) score and visual analogue scale to assess the functional situation of the patients before operation, 1 week after operation, 1 month after operation, 6 months after operation, and the last follow up. Results: The operating time(83.1±7.3 vs 86.1±9.6 min), intraoperative blood loss(18.2±3.9 vs 40.5±13.3 ml), postoperative duration in bed(37.4±7.8 vs 63.7±15.8 h), as well as length of hospital stay (3.8±1.1 vs 6.5±2.0 d)were all obviously better in tubular paraspinal approach group than in traditional semi-laminar approach group(P<0.05). The postoperative 1 week, 1month, and 6 months JOA score (21.8±3.4, 23.6±2.4, 24.2±2.4 vs 19.9±3.7, 21.6±2.8, 22.4±2.1)and VAS (2.2±1.0, 2.0±1.1, 0.4±0.1 vs 3.1±1.2, 2.6±1.3, 0.5±0.1) were better in tubular paraspinal approach group than semi-laminar approach group (P<0.05). While at the last follow up, the JOA score and VAS were similar in the 2 groups (P>0.05) . Conclusions: In non-fusion techniques for treating lumbar stenosis, tubular paraspinal approach demonstrated less blood loss, shorter stay in bed as well as in hospital, and better symptom relief in early postoperative period than traditional semi-laminal approach. While at long term follow up, both approaches achieved satisfactory outcome.

How I do it? Uniportal full endoscopic contralateral approach for lumbar foraminal stenosis with double crush syndrome

Background

Evolution of endoscopic surgery provides equivalent results to open surgery with advantages of minimal invasive surgery. The literature on technique Uniportal Full endoscopic contralateral approach is scarce.

Methods

The endoscopic contralateral approach technique applies for patients presenting with double crush syndrome with foraminal and extraforminal stenosis. The key steps focus on contralateral ventral overriding superior articular process decompression, foraminal and extraforaminal discectomy, and lateral vertebral syndesmophyte decompression leading to enlargement of the contralateral foramen and extraforamen size.

Conclusion

The Uniportal Full endoscopic contralateral approach is a good alternative to open surgery or minimally invasive microscopic surgery through direct endoscopic visualization of the entire route of exiting nerve with no neural retraction allowing both lateral recess and foraminal and extraforaminal decompression all in one approach.

Electronic supplementary material

The online version of this article (10.1007/s00701-019-04157-z) contains supplementary material, which is available to authorized users.

Incidence and Implications of Incidental Durotomy in Transforaminal Endoscopic Spine Surgery: Case Series

OBJECTIVE

To evaluate the incidence and outcomes of incidental durotomy in transforaminal endoscopic spine surgery.

METHODS

Transforaminal lumbar endoscopic procedures were performed by 2 surgeons in 907 patients over a period of 4 years from 2014 to 2018. Patient data were evaluated retrospectively in these patients with a minimum follow-up of 1 year.

RESULTS

In 907 patients over 4 years there were 5 durotomies: 4 incidental and 1 intentional. The rate for incidental durotomy was therefore 0.4%. There were no adverse outcomes from the incidental durotomies, and only 1 patient noted a headache.

CONCLUSIONS

Incidental durotomy is a rare complication of transforaminal lumbar endoscopic spine surgery and appears to occur more likely in patients who have undergone previous spine surgery at the site of the endoscopic procedure, not unexpectantly. Glues, patches, and bedrest were among the various methods used after durotomy. In this series there were no cases of symptomatic spinal fluid leakage or pseudomeningocele seen. Only 20% of patients who had durotomies noted a headache in the immediate postoperative period.

How I do it? Transforaminal endoscopic decompression of intraspinal facet cyst

BACKGROUND

Transforaminal endoscopic surgery provides equivalent results to open surgery with added advantages of feasibility under local anesthesia, no injury to posterior elements, preservation of the ligamentum flavum, ease of revision surgery, and cost-effectiveness. The technique of transforaminal endoscopic excision of cysts of facet or zygapophyseal joints is scarcely described in literature.

METHODS

The transforaminal endoscopy is applicable to cyst lying in the extraforaminal, foraminal, and intraspinal regions. The "mobile" outside-in technique combined with osteotomy of the tip of the superior articular process facilitates intraspinal access for complete decompression.

CONCLUSION

Transforaminal endoscopic removal of the facet cyst is a viable alternative to traditional open surgery with added advantages of a minimal access procedure.

Endoscopic Surgical Technique for Treating Sacral Radiculopathy Secondary to S1 Nerve Compression After Minimally Invasive Sacroiliac Joint Fusion: Technical Note

BACKGROUND

Sacroiliac (SI) joint fusion is considered for the treatment of degenerative sacroiliitis. The procedure has increased in popularity for patients who have exhausted less invasive treatment options since the development of percutaneous SI joint fusion systems. One possible complication of the procedure is a sacral radiculopathy that can result from compression of the S1 nerve by the SI joint fusion implant. Others have described revising the implant by removing it and replacing it with a shorter implant.

METHODS

Here we describe a minimally invasive endoscopic S1 nerve root decompression that does not require removing or revising the SI fusion implant.

RESULTS

The postoperative course was uneventful, and the patient's radicular pain improved immediately after surgery. Six months after his endoscopic procedure, the patient had no clinical symptoms related to the S1 nerve root compression and was symptomatically improved from her sacroiliac pain.

CONCLUSIONS

This technical note is for others to consider as a possible minimally invasive solution for the treatment of lumbar radiculopathy after a minimally invasive SI joint fusion procedure.

Real-time fusion-imaging in low back pain: a new navigation system for facet joint injections

AIMS AND OBJECTIVES

The aim of the current study is to present our experience in lumbar spine interventional procedures performed with a newly developed multimodal echo-navigator (EcoNav) and to evaluate short-term clinical outcomes of a series of patients affected by facet joint disease (FJD) treated with steroid and anaesthetic injection under fusion-imaging guidance, compared to a cohort of patients that received the same treatment under computed tomography (CT) guidance.

METHODS

Sixty-five consecutive patients (34 females; mean age 68.3 ± 12.8 years) with a clinical diagnosis of non-radicular low back pain lasting for more than 6-weeks and magnetic resonance (MR) or CT confirmed FJD were enrolled for image-guided FJI. Twenty-eight patients underwent FJI with fusion-guided technique, while CT-guided procedures were performed in the other cases. Clinical and procedural data were recorded and compared at a mean follow-up of 6.1 ± 2.0 months.

RESULTS

A significant improvement in clinical parameters was observed for both fusion-guided and CT-guided group. Comparing both groups, no statistically significant difference could be detected neither at baseline conditions nor during the follow-up period. No significant periprocedural complication occurred in both groups. A satisfaction rate of 92.3 and 81.1% was reported for fusion-guided and CT-guided group, respectively.

CONCLUSION

EcoNav fusion-imaging system represents a safe, feasible, effective and reproducible guidance option in FJD infiltration procedures, also avoiding use of ionising radiations.

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF): surgical technique, long-term 4-year prospective outcomes, and complications compared with an open TLIF cohort

Transforaminal lumbar interbody fusion (TLIF) is an important surgical option for the treatment of back pain and radiculopathy. The minimally invasive TLIF (MI-TLIF) technique is increasingly used to achieve neural element decompression, restoration of segmental alignment and lordosis, and bony fusion. This article reviews the surgical technique, outcomes, and complications in a series of 144 consecutive 1- and 2-level MI-TLIFs in comparison with an institutional control group of 54 open traditional TLIF procedures with a mean of 46 months' follow-up. The evidence base suggests that MI-TLIF can be performed safely with excellent long-term outcomes.

Minimally invasive thoracic decompression for multi-level thoracic pathologies

We describe our experience using a minimal access approach for multi-level dorsal decompression of the thoracic spine that may limit approach-related soft-tissue injury and spinal destabilization. Additionally, three patients, each with unique compressive thoracic pathology, are discussed. A single minimal access technique, using multi-level hemilaminotomies, was used to address these unique pathologies via a similar approach. The three patients in this study had a mean age of 49.3 years (range: 45-55 years), mean estimated blood loss of 750 cc (range: 350-1000 cc), mean operative time of 3.8 hours (range: 3-5 hours), and a mean post-operative hospital stay of 2.3 days (range: 2-3 days). Complete decompression was achieved with resolution of symptoms in all patients. Long-term follow-up averaged 26.7 months (range: 15-36 months). Radiographic decompression was demonstrated in all patients. Minimal access techniques using muscle-splitting tubular retractor systems can effectively treat multi-level dorsal compression of the thoracic cord, while potentially limiting morbidity and long-term spinal instability.

Clinical and radiographic outcomes after minimally invasive transforaminal lumbar interbody fusion

OBJECTIVE

To evaluate outcomes after minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).

BACKGROUND

MI-TLIF is a relatively novel technique for treating symptomatic spondylolisthesis and degenerative disc disease of the lumbar spine. It has become a popular option for lumbar arthrodesis largely because of its potential to minimize iatrogenic trauma to the soft tissue, paraspinous muscles as well as to neural elements.

METHODS

Literature search using PubMed database.

RESULTS

Eight retrospective clinical studies and 1 prospective clinical study were identified. No randomized studies were found. The indications for surgery were low-back pain and/or radicular symptoms secondary to spondylolisthesis and/or degenerative disc disease. Analysis of radiographic outcomes demonstrated a fusion rate greater than 90% in the vast majority of patients. Patients also experienced a significant improvement in functional outcome parameters at a mean follow-up of 20 months. Comparison of functional outcomes of MI-TLIF patients to a similar matched cohort of patients who underwent conventional open TLIF did not demonstrate any statistically significant difference between both cohorts.

CONCLUSION

For carefully selected patients, MI-TLIF has a very favorable long term outcome that is comparable to conventional open TLIF, with the added benefit of decreased adjacent tissue injury.