Prone transpsoas lumbar corpectomy: simultaneous posterior and lateral lumbar access for difficult clinical scenarios

Single Position Prone Lateral Lumbar Interbody Fusion: A Review of the Current Literature

PURPOSE OF REVIEW

Spinal fusion, vital for treating various spinal disorders, has evolved since the introduction of the minimally invasive Lateral Lumbar Interbody Fusion (LLIF) by Pimenta in 2001. Traditionally performed in the lateral decubitus position, LLIF faces challenges such as intraoperative repositioning, neurological complications, and lack of access to lower lumbar levels. These challenges lead to long surgery times, increased rates of perioperative complications, and increased costs. The more recently popularized prone lateral approach mitigates these issues primarily by eliminating patient repositioning, thereby enhancing surgical efficiency, and reducing operative times. This review examines the progression of spinal fusion techniques, focusing on the advantages and recent findings of the prone lateral approach compared to the traditional LLIF.

RECENT FINDINGS

The prone lateral approach has shown improved patient outcomes, including lower blood loss and shorter hospital stays, and has been validated by multiple studies for its safety and efficacy compared to the LLIF approach. Significant enhancements in postoperative metrics, such as the Oswestry Disability Index, Visual Analog Scale, and radiological improvements have been noted. Comparatively, the prone lateral approach offers superior segmental lordosis correction and potentially better subjective outcomes than the lateral decubitus position. Despite these advances, both techniques present similar risks of neurological complications. Overall, the prone lateral approach has emerged as a promising alternative in lumbar interbody fusion, combining efficiency, safety, and improved clinical outcomes.

Advancing Prone-Transpsoas Spine Surgery: A Narrative Review and Evolution of Indications with Representative Cases

The Prone Transpsoas (PTP) approach to lumbar spine surgery, emerging as an evolution of lateral lumbar interbody fusion (LLIF), offers significant advantages over traditional methods. PTP has demonstrated increased lumbar lordosis gains compared to LLIF, owing to the natural increase in lordosis afforded by prone positioning. Additionally, the prone position offers anatomical advantages, with shifts in the psoas muscle and lumbar plexus, reducing the likelihood of postoperative femoral plexopathy and moving critical peritoneal contents away from the approach. Furthermore, operative efficiency is a notable benefit of PTP. By eliminating the need for intraoperative position changes, PTP reduces surgical time, which in turn decreases the risk of complications and operative costs. Finally, its versatility extends to various lumbar pathologies, including degeneration, adjacent segment disease, and deformities. The growing body of evidence indicates that PTP is at least as safe as traditional approaches, with a potentially better complication profile. In this narrative review, we review the historical evolution of lateral interbody fusion, culminating in the prone transpsoas approach. We also describe several adjuncts of PTP, including robotics and radiation-reduction methods. Finally, we illustrate the versatility of PTP and its uses, ranging from 'simple' degenerative cases to complex deformity surgeries.

Single-Position Transpsoas Corpectomy and Posterior Instrumentation in the Thoracolumbar Spine for Different Clinical Scenarios

BACKGROUND

The concept of single-position spine surgery has been gaining momentum because it has proven to reduce operative time, blood loss, and hospital length of stay with similar or better outcomes than traditional dual-position surgery. The latest development in single-position spine surgery techniques combines either open or posterior pedicle screw fixation with transpsoas corpectomy while in the lateral or prone positioning.

OBJECTIVE

To provide, through a multicenter study, the results of our first patients treated by single-position corpectomy.

METHODS

This is a multicenter retrospective study of patients who underwent corpectomy and instrumentation in the lateral or prone position without repositioning between the anterior and posterior techniques. Data regarding demographics, diagnosis, neurological status, surgical details, complications, and radiographic parameters were collected. The minimum follow-up for inclusion was 6 months.

RESULTS

Thirty-four patients were finally included in our study (24 male patients and 10 female patients), with a mean age of 51.2 (SD ± 17.5) years. Three-quarter of cases (n = 27) presented with thoracolumbar fracture as main diagnosis, followed by spinal metastases and primary spinal infection. Lateral positioning was used in 27 cases, and prone positioning was used in 7 cases. The overall rate of complications was 14.7%.

CONCLUSION

This is the first multicenter series of patients who underwent single-position corpectomy and fusion. This technique has shown to be safe and effective to treat a variety of spinal conditions with a relatively low rate of complications. More series are required to validate this technique as a possible standard approach when thoracolumbar corpectomies are indicated.

Technical nuances and approach-related morbidity of anterolateral and posterolateral lumbar corpectomy approaches-a systematic review of the literature

Purpose

Approaches for lumbar corpectomies can be roughly categorized into anterolateral (AL) and posterolateral (PL) approaches. It remains controversial to date whether one approach is superior to the other, and no comparative studies exist for the two approaches for lumbar corpectomies.

Methods

A systematic review of the literature was performed through a MEDLINE/PubMed search. Studies and case reports describing technique plus outcomes and possible complications were included. Thereafter, estimated blood loss (EBL), length of operation (LOO), utilized implants, neurological outcomes, complication rates, and reoperation rates were analyzed.

Results

A total of 64 articles reporting on 702 patients including 513 AL and 189 PL corpectomies were included in this paper. All patients in the PL group were instrumented via the same approach used for corpectomy, while in the AL group the majority (68.3%) of authors described the use of an additional approach for instrumentation. The EBL was higher in the AL group (1393 ± 1341 ml vs. 982 ± 567 ml). The LOO also was higher in the AL group (317 ± 178 min vs. 258 ± 93 min). The complication rate (20.5% vs. 29.1%, p = 0.048) and the revision rate (3.1% vs. 9.5%, p = 0.004) were higher in the PL group. Neurological improvement rates were 43.8% (AL) vs. 39.2% (PL), and deterioration was only noted in the AL group (6.0%), while 50.2% (AL) and 60.8% (PL) showed no change from initial presentation to the last follow-up.

Conclusion

While neurological outcomes of both approaches are comparable, the results of the present review demonstrated lower complication and revision rates in anterolateral corpectomies. Nevertheless, individual patient characteristics must be considered in decision-making.

Outpatient outcomes of patients with femoral nerve neurapraxia after prone lateral lumbar interbody fusion at L4-5

OBJECTIVE

Single-position prone lateral lumbar interbody fusion (LLIF) improves the efficiency of staged minimally invasive lumbar spine surgery. However, laterally approaching the lumbar spine, especially L4-5 with the patient in the prone position, could increase the risk of complications and presents unique challenges, including difficult ergonomics, psoas migration, and management of the nearby lumbar plexus. The authors sought to identify postoperative femoral neurapraxia after single-position prone LLIF at L4-5 to better understand how symptoms evolve over time.

METHODS

This retrospective analysis examined a prospectively maintained database of LLIF patients who were treated by two surgeons (J.S.U. and J.D.T.). Patients who underwent single-position prone LLIF at L4-5 and percutaneous pedicle screw fixation for lumbar stenosis or spondylolisthesis were included if they had at least 6 weeks of follow-up. Outpatient postoperative neurological symptoms were analyzed at 6-week, 3-month, and 6-month follow-up evaluations.

RESULTS

Twenty-nine patients (16 women [55%]; overall mean ± SD age 62 ± 11 years) met the inclusion criteria. Five patients (17%) experienced complications, including 1 (3%) who had a femoral nerve injury with resultant motor weakness. The mean ± SD transpsoas retractor time was 14.6 ± 6.1 minutes, the directional anterior electromyography (EMG) threshold before retractor placement was 20.1 ± 10.2 mA, and the directional posterior EMG threshold was 10.4 ± 9.1 mA. All patients had 6-week clinical follow-up evaluations. Ten patients (34%) reported thigh pain or weakness at their 6-week follow-up appointment, compared with 3/27 (11%) at 3 months and 1/20 (5%) at 6 months. No association was found between directional EMG threshold and neurapraxia, but longer transpsoas retractor time at L4-5 was significantly associated with femoral neurapraxia at 6-week follow-up (p = 0.02). The only case of femoral nerve injury with motor weakness developed in a patient with a retractor time that was nearly twice as long as the mean time (27.0 vs 14.6 minutes); however, this patient fully recovered by the 3-month follow-up evaluation.

CONCLUSIONS

To our knowledge, this is the largest study with the longest follow-up duration to date after single-position prone LLIF at L4-5 with percutaneous pedicle screw fixation. Although 34% of patients reported ipsilateral sensory symptoms in the thigh at the 6-week follow-up evaluation, only 1 patient sustained a nerve injury; this resulted in temporary weakness that resolved by the 3-month follow-up evaluation. Thus, longer transpsoas retractor time at L4-5 during prone LLIF is associated with increased ipsilateral thigh symptoms at 6-week follow-up that may resolve over time.