Minimally invasive spine surgery: a historical perspective

Minimally invasive lateral single-position surgery for multilevel degenerative lumbar spine disease: feasibility and perioperative results in a single Latin-American spine center

INTRODUCTION

Within advances in minimally invasive spine surgery, the implementation of lateral single position (LSP) increases efficiency while limiting complications, avoiding intraoperative repositioning and diminishing surgical time. Most literature describes one-level instrumentation of the lumbar spine; this study includes the use of LSP for multilevel degenerative disease.

OBJECTIVE

The objective of the article is to analyze initial clinical results and complications in the use of LSP for multiple level instrumentation in adults with lumbar degenerative disease.

METHODS

A retrospective early clinical series was performed for patients who had multiple level instrumentation in LSP between August 2019 and September 2022 at the Hospital Universitario San Ignacio in Bogota, Colombia. Inclusion criteria were patients older than 18 years with symptomatic lumbar degenerative disease, undergoing any combination of multilevel anterior lumbar interbody fusion, lateral lumbar interbody fusion (LLIF) and pedicle screw fixation.

RESULTS

Forty patients with an average age of 61.3 years were included, with diagnosis of multilevel degenerative spondylotic changes. Four-, three- and two-level interventions were performed in 52.5, 35 and 12.5%, respectively. Average time per level was 68.9 min, and length of hospital stay had an average of 2.4 days, with all patients starting ambulation within the first postoperative day.

CONCLUSION

Procedural time and blood loss were similar to those reported in literature. No severe lesions, postoperative infections or reinterventions took place. Although it was a small number of patients and further clinical trials are needed, LSP for multiple levels is apparently safe with adequate outcomes which may improve efficiency in the operating room.

Endoscopic Spine Surgery in Athletes: Case Series and Review of Literature

BACKGROUND

Degenerative spine disease is common in athletes and can progress to requiring surgical intervention. Traditional open surgical techniques necessitate prolonged recovery time and time away from play. Newly developed endoscopic surgical techniques may promote faster healing and recovery, and increased return to play. The goal of this paper is to summarize the current evidence in return to play after spine surgery and to present our series of 3 athletes who underwent endoscopic spine surgery.

METHODS

A complete search of all PubMed indexed articles pertaining to spine surgery in athletes was conducted. This was supplemented by a 3-patient case series of our own endoscopic spine experience in athletes.

RESULTS

There are no current widely accepted guidelines for return to play after spinal surgery. The best evidence available cites a return to play of 81% at 5.2-8.7 months after traditional open and minimally invasive surgery, and endoscopic surgery produces an average 88% return to play rate at 3 months.

CONCLUSIONS

Although return to play can vary widely, case-based evidence as well as biomechanical principles support endoscopic spine surgery as a viable surgical modality for the treatment of spinal pathologies in athletes.

Access to Technology and Education for the Development of Minimally Invasive Spine Surgery Techniques in Latin America

OBJECTIVE

To evaluate access to the technologies and education needed to perform minimally invasive spine surgery (MISS) in Latin America.

METHODS

We designed a questionnaire to evaluate surgeons' practice characteristics, access to different technologies, and training opportunities for MISS techniques. The survey was sent to members and registered users of AO Spine Latin from January 6-20, 2020. The major variables studied were nationality, specialty (orthopedics or neurosurgery), level of hospital (primary, secondary, tertiary), number of surgeries performed per year by the spine surgeon, types of spinal pathologies commonly managed, and number of MISS performed per year. Other variables involved specific access to different technologies: intraoperative fluoroscopy, percutaneous screws, cages, tubular retractors, microscopy, intraoperative computed tomography, neuronavigation imaging, and bone morphogenetic protein. Finally, participants were asked about main obstacles to performing MISS and their access to education on MISS techniques in their region.

RESULTS

The questionnaires were answered by 306 members of AO Spine Latin America across 20 different countries. Most answers were obtained from orthopedic surgeons (57.8%) and those with over 10 years of experience (42.4%). Most of the surgeons worked in private practice (46.4%) and performed >50 surgeries per year (44.1%), but only 13.7% performed >50 MISS per year, mainly to manage degenerative pathologies (87.5%). Most surgeons always had access to fluoroscopy (79%). Only 26% always had access to percutaneous screws, 24% to tubular retractors, 34.3% to cages (anterior lumbar interbody fusion, lateral lumbar interbody fusion, or transforaminal lumbar interbody fusion), and 43% to microscopy. Regarding technologies, 71% reported never having access to navigation, 83% computed tomography, and 69.3% bone morphogenetic protein. The main limitations expressed for widely used MISS technologies were the high implant costs (69.3%) and high navigation costs (49.3%). Most surgeons claimed access to online education activities (71%), but only 44.9% reported access to face-to-face events and 28.8% to hands-on activities, their limited access largely because the courses were expensive (62.7%) or few courses were available on MISS in their region (51.3%).

CONCLUSIONS

Most surgeons in Latin America have limited resources to perform MISS, even in private practice. The main constraints are implant costs, access to technologies, and limited face-to-face educational opportunities.

Association of Cost Savings and Surgical Quality With Single-Vendor Procurement for Spinal Implants

IMPORTANCE

Significant cost savings can be achieved from consolidating purchases of spinal implants with a single vendor. However, it is currently unknown whether sole-source contracting or vendor rationalization more broadly affects patient care.

OBJECTIVES

To describe the single-vendor procurement of spinal implants, characterize the economic benefits of sole-source contracting, and gauge whether vendor rationalization is associated with a diminished quality of care.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study assessed adult patients receiving single-level lumbar interbody fusions at a single institution from January 1, 2009, to July 31, 2017. Exclusion criteria included multilevel fusions and prior spinal fusions.

EXPOSURES

Patients were analyzed based on the number of vendors available to surgeons at the time of the patient's surgery. January 1, 2009, to December 31, 2010, was defined as the multivendor period (10 vendors); January 1, 2011, to December 31, 2014, was defined as the dual-vendor period; and January 1, 2015, to July 31, 2017, was defined as the single-vendor period.

MAIN OUTCOMES AND MEASURES

Rates of 12-month revision surgery, complications, 30-day readmissions, and postoperative patient-reported outcomes, as measured by 5-dimension European Quality of Life (EQ-5D) and Patient-Reported Outcomes Measurement Information System-Global Health (PROMIS-GH) utilities. Propensity score weighting was performed to control for confounding. The Holm method was used to correct for multiple testing. Annual cost savings associated with the dual-vendor and single-vendor periods were also reported.

RESULTS

A total of 1373 patients (mean [SD] age, 59.2 [12.6] years; 763 [55.6%] female; 1161 [84.6%] white) were analyzed. Rates of revisions after adjusting for confounding were 3.2% (95% CI, 1.5%-6.7%) for the multivendor period, 4.5% (95% CI, 3.1%-6.5%) for the dual-vendor period, and 3.0% (95% CI, 1.7%-5.0%) for the single-vendor period. Complication rates were 5.3% (95% CI, 2.7%-10.1%) for the multivendor period, 7.2% (95% CI, 5.4%-9.6%) for the dual-vendor period, and 6.4% (95% CI, 4.6%-8.8%) for the single-vendor period. Readmission rates were 14.2% (95% CI, 9.7%-20.2%) for the multivendor period, 12.6% (95% CI, 10.1%-15.5%) for the dual-vendor period, and 9.7% (95% CI, 7.4%-12.7%) for the single-vendor period. Revisions, complications, and patient-reported outcomes were statistically equivalent across all periods. Readmissions were not statistically equivalent but not statistically different. The savings attributable to vendor rationalization were 24% for the dual-vendor and 21% for the single-vendor periods.

CONCLUSIONS AND RELEVANCE

The single-vendor procurement of spinal implants was associated with significant cost savings without evidence of an associated decline in the quality of care. Large hospital systems may consider sole-source purchasing as a viable cost reduction strategy.

Open versus minimally invasive TLIF: literature review and meta-analysis

STUDY DESIGN

This study is a comparative, literature review.

OBJECTIVE

The aim of this study is to provide a comparative analysis of open vs. minimally invasive TLIF using a literature review and a meta-analysis. Lumbar interbody fusion is a well-established surgical procedure for treating several spinal disorders. Transforaminal lumbar interbody fusion (TLIF) was initially introduced in the early 1980s. To reduce approach-related morbidity associated with traditional open TLIF (OTLIF), minimally invasive TLIF (MITLIF) was developed. We aimed to provide a comparative analysis of open vs. minimally invasive TLIF using a literature review.

METHODS

We searched the online database PubMed (2005-2017), which yielded an initial 194 studies. We first searched the articles' abstracts. Based on our inclusion criteria, we excluded 162 studies and included 32 studies: 18 prospective, 13 retrospective, and a single randomized controlled trial. Operative time, blood loss, length of hospital stay, radiation exposure time, complication rate, and pain scores (visual analogue scale, Oswestry Disability Index) for both techniques were recorded and presented as means. We then performed a meta-analysis.

RESULTS

The meta-analysis for all outcomes showed reduced blood loss (P < 0.00001) and length of hospital stay (P < 0.00001) for MITLIF compared with OTLIF, but with increased radiation exposure time with MITLIF (P < 0.00001). There was no significant difference in operative time between techniques (P = 0.78). The complication rate was lower with MITLIF (11.3%) vs. OTLIF (14.2%), but not statistically significantly different (P = 0.05). No significant differences were found in visual analogue scores (back and leg) and Oswestry Disability Index scores between techniques, at the final follow-up.

CONCLUSION

MITLIF and OTLIF provide equivalent long-term clinical outcomes. MITLIF had less tissue injury, blood loss, and length of hospital stay. MITLIF is also a safe alternative in obese patients and, in experienced hands, can also be used safely in select cases of spondylodiscitis even with epidural abscess. MITLIF is also a cost-saving procedure associated with reduced hospital and social costs. Long-term studies are required to better evaluate controversial items such as operative time.

[Decompression by mini-open posterior approach assisted with microscope for thoracolumbar burst fracture with severe spinal canal stenosis]

Objective

To investigate the effectiveness of posterior microscopic mini-open technique (MOT) decompression in patients with severe spinal canal stenosis resulting from thoracolumbar burst fractures.

Methods

The clinical data of 28 patients with severe spinal canal stenosis caused by thoracolumbar burst fractures, who were treated by posterior microscopic MOT, which performed unilateral or bilateral laminectomy, poking reduction, intervertebral bone graft via spinal canal, and percutaneous pedicle screw fixation between January 2014 and January 2016 were retrospectively analyzed. There were 21 males and 7 females with a mean age of 42.1 years (range, 16-61 years). The involved segments included T 11 in 1 case, T 12 in 4 cases, L 1 in 14 cases, and L 2 in 9 cases. According to AO classification, there were 19 cases of type A3, 9 of type A4. According to American Spinal Injury Association (ASIA) grading, 12 cases were grade C, 13 grade D, and 3 grade E. The time between injury and operation was 3-7 days (mean, 3.6 days). To evaluate effectiveness, the changes in the visual analogue scale (VAS), percentage of anterior height of injured vertebrae, Cobb angle, rate of spinal compromise (RSC), and ASIA grading were analyzed.

Results

All patients were performed procedures successfully. The operation time was 135-323 minutes (mean, 216.4 minutes). The intraoperative blood loss was 80-800 mL (mean, 197.7 mL). The hospitalization time was 10-25 days (mean, 12.5 days). The incisions healed primarily, without wound infection, cerebrospinal fluid leakage, or other early complications. All the 28 patients were followed up 12-24 months (mean, 16.5 months). No breakage or loosening of internal fixation occurred. All fractures healed, and the healing time was 3-12 months (mean, 6.5 months). Compared with preoperative ones, the percentage of anterior height of injured vertebrae, Cobb angle, and RSC at immediate after operation and at last follow-up and the VAS scores at 1 day after operation and at last-follow were significantly improved ( P<0.05). There was no significant difference in the percentage of anterior height of injured vertebrae and Cobb angle between at immediate after operation and at last follow-up ( P>0.05). But the RSC at immediate after operation and VSA score at 1 day after operation were significantly improved when compared with those at last follow-up ( P<0.05). The ASIA grading at last follow-up was 1 case of grade C, 14 grade D, and 13 grade E, which was significantly improved when compared with preoperative ones ( Z=3.860, P=0.000).

Conclusion

MOT is an effective and minimal invasive treatment for thoracolumbar AO type A3 and A4 burst fractures with severe spinal canal stenosis, and it is beneficial to early rehabilitation for patients.

Operative Management of a Sacral Gunshot Injury via Minimally Invasive Techniques and Instrumentation

Gunshot wounds to the spine account for 13% to 17% of all gunshot injuries and occur predominantly in the thoracic region. Minimally invasive spine surgery procedures implementing serial muscle dilation and the use of a tubular retracting system with a working channel minimize soft tissue trauma, facilitate less bony and soft tissue resection, decrease blood loss, minimize scarring and improve cosmesis, decrease hospitalization, and reduce postoperative pain and narcotic usage in comparison to more open, traditional approaches. Although minimally invasive spine surgery techniques and instrumentation have gained considerable attention, their application in the management of gunshot injuries to the sacrum has not been reported. The following is a brief case report of a 21-year-old male who sustained a gunshot injury to the sacrum who was managed operatively via minimally invasive spine surgery techniques and instrumentation.

Use of a quantitative pedicle screw accuracy system to assess new technology: Initial studies on O-arm navigation and its effect on the learning curve of percutaneous pedicle screw insertion

Background

A quantitative screw accuracy system is proposed that allows for high-fidelity discrimination between various methods of pedicle screw insertion. Our purpose was to study the utility of a quantitative screw accuracy scoring system to assess new imaging technologies and their effects on the minimally invasive spine learning curve.

Methods

By use of a hypothetical “perfect screw,” a scoring system is proposed that may be used to compare the position of a small number of screws inserted according to a desired optimal position. This study incorporates a retrospective review of imaging studies for 10 patients who underwent percutaneous pedicle screw placement with either navigation-assisted O-arm imaging or navigation-assisted C-arm imaging. For the learning-curve portion of the study, 2 cadaveric adult torsos were used for instrumentation. Computed tomography imaging studies were used in both studies to assess screw position in the pedicle and vertebral body in relation to an optimal screw by use of a quantitative scoring system to rate accuracy.

Results

The quantitative scoring system allowed a statistically significant accuracy difference to be ascertained between 2 different technologies using fewer data points than previously published methods. When this screw scoring system is applied to minimally invasive percutaneous pedicle screw insertion, an optimal screw position can be achieved with greater accuracy through navigation-assisted technology (O-arm with computer-assisted navigation). When the O-arm with computer-assisted navigation was used by a novice surgeon learning the technique of percutaneous screw insertion, screws were inserted in a shorter period without loss of accuracy. In contrast, use of the traditional C-arm fluoroscopy leads to a loss of accuracy with faster insertion times. Increased accuracy can be seen clinically when compared with fluoroscopic navigation.

Conclusions

The use of a quantitative scoring system allows for rapid assessment of screw accuracy. As additional technologies and new teaching techniques for pedicle screw insertion are developed, this scoring system may be useful as an early assessment tool.

Minimally invasive burst fracture fixation in the thoracolumbar region

Minimally invasive spine surgery is evolving rapidly. Compared with the traditional posterior approach with long and wide exposure, the minimally invasive approach offers significant advantages in treating patients with spine trauma.

Maximizing the potential of minimally invasive spine surgery in complex spinal disorders

Minimally invasive surgery (MIS) in the spine was primarily developed to reduce approach-related morbidity and to improve clinical outcomes compared with those following conventional open spine surgery. Over the past several years, minimally invasive spinal procedures have gained recognition and their utilization has increased. In particular, MIS is now routinely used in the treatment of degenerative spine disorders and has been shown to be as effective as conventional open spine surgeries. Although the procedures are not yet widely recognized in the context of complex spine surgery, the true potential in minimizing approach-related morbidity is far greater in the treatment of complex spinal diseases such as spinal trauma, spinal deformities, and spinal oncology. Conventional open spine surgeries for complex spinal disorders are often associated with significant soft tissue disruption, blood loss, prolonged recovery time, and postsurgical pain. In this article the authors review numerous cases of complex spine disorders managed with MIS techniques and discuss the current and future implications of these approaches for complex spinal pathologies.

Surgeon Perceptions of Minimally Invasive Spine Surgery

BACKGROUND: Interest in minimally invasive surgery (MIS) of the spine has driven the development of new and innovative techniques to treat an ever wider range of spinal disorders. Despite these new advances, spine surgeons have been slow in adopting MIS into their clinical practice. This study aims to provide a better understanding of the factors that have led to limited incorporation of these procedures into their practices. METHODS: Eighty-seven spine surgeons completed a questionnaire related to their perceptions of MIS. Respondents were asked to comment on their perceptions regarding the limitations and advantages of minimally invasive spine surgery. Survey results were then analyzed for both overall opinions and opinions based on the amount of MIS utilization in the respondents' current practices. RESULTS: The top 3 identified limitations of MIS of the spine were technical difficulty, lack of convenient training opportunities, and radiation exposure. Of these respondents, spine surgeons experienced in MIS were concerned more with radiation exposure than the lack of training opportunities. In contrast, spine surgeons with little MIS experience cited the lack of training opportunities as the most significant limitation. There was little concern related to the limited proven clinical efficacy of MIS of the spine. DISCUSSION: Technical factors, training opportunities, and radiation exposure appear to be the major obstacles to MIS of the spine. Most spine surgeons believe that MIS leads to faster return to daily activities, better long-term function, and decreased hospitalization. This may explain why most surgeons did not cite a lack of proven efficacy as a major limitation to MIS. These findings indicate that the widespread adoption of MIS of the spine will likely be driven through relatively simple means, such as improved training programs that strive to decrease the technical difficulty and limit radiation exposure of these procedures. It is unlikely that extensive clinical data alone, without such improved training programs, will be sufficient to drive widespread use of minimally invasive spine surgery.

Surgeon Perceptions of Minimally Invasive Spine Surgery

Background

Interest in minimally invasive surgery (MIS) of the spine has driven the development of new and innovative techniques to treat an ever wider range of spinal disorders. Despite these new advances, spine surgeons have been slow in adopting MIS into their clinical practice. This study aims to provide a better understanding of the factors that have led to limited incorporation of these procedures into their practices.

Methods

Eighty-seven spine surgeons completed a questionnaire related to their perceptions of MIS. Respondents were asked to comment on their perceptions regarding the limitations and advantages of minimally invasive spine surgery. Survey results were then analyzed for both overall opinions and opinions based on the amount of MIS utilization in the respondents’ current practices.

Results

The top 3 identified limitations of MIS of the spine were technical difficulty, lack of convenient training opportunities, and radiation exposure. Of these respondents, spine surgeons experienced in MIS were concerned more with radiation exposure than the lack of training opportunities. In contrast, spine surgeons with little MIS experience cited the lack of training opportunities as the most significant limitation. There was little concern related to the limited proven clinical efficacy of MIS of the spine.

Discussion

Technical factors, training opportunities, and radiation exposure appear to be the major obstacles to MIS of the spine. Most spine surgeons believe that MIS leads to faster return to daily activities, better long-term function, and decreased hospitalization. This may explain why most surgeons did not cite a lack of proven efficacy as a major limitation to MIS.

These findings indicate that the widespread adoption of MIS of the spine will likely be driven through relatively simple means, such as improved training programs that strive to decrease the technical difficulty and limit radiation exposure of these procedures. It is unlikely that extensive clinical data alone, without such improved training programs, will be sufficient to drive widespread use of minimally invasive spine surgery.