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Pham, Martin H.

https://orcid.org/0000-0002-7733-8902

Mayo Clinic

University of California San Diego

Citations 10

Single-position robot-assisted lateral lumbar corpectomy with minimally invasive posterior spinal fusion for traumatic burst fracture showing MRI-demonstrated indirect decompression: illustrative case
Fraipont, Genevieve , Pennington, Zach , Diaz-Aguilar, Luis Daniel , Pham, Martin H. , Fraipont, Genevieve M , Pennington, Zach , Pham, Martin H , Beyer, Ryan S.

Journal of Neurosurgery: Case Lessons | July 22, 2026 | Volume: 12 | Issue: 3 | Pages: No page available

10.3171/case26118 Get It

BACKGROUND Ligamentotaxis-based indirect decompression using lateral approaches is well described for degenerative lumbar disease, yet its application in managing burst fractures remains underexplored. OBSERVATIONS A 72-year-old osteopenic male with an L4 burst fracture underwent a single-position robot-assisted lateral L4 corpectomy, L2–3 oblique lumbar interbody fusion, L5–S1 lateral anterior lumbar interbody fusion, and robot-assisted percutaneous segmental fixation from L2 to the ilium. Postoperative MRI demonstrated significant indirect decompression with a decrease in ligamentous buckling and restoration of the spinal canal cross-sectional area. The ligamentotaxis created by the height and lordosis restoration produced adequate decompression without resection of the ventral retropulsed fragments or posterior direct decompression. LESSONS This case illustrates that single-position lateral lumbar corpectomy can achieve indirect decompression while sparing the morbidity of an open posterior approach. To the authors’ knowledge, this is the first report with MRI evidence of indirect decompression following single-position lateral lumbar corpectomy. https://thejns.org/doi/10.3171/CASE26118
The Scarlet Letter of the Unmatched Neurosurgery Reapplicant: Trends, Opinions, and Guidance from a Nationwide Survey
Cole, Kyril L. , Sagher, Oren , Pham, Martin H. , Cook, Steven, Cole, Chad , Spinner, Robert J. , Murad, Gregory J. A. , Couldwell, William T. , Jensen, Randy L. , Group, the Unmatched Applicants Study, Van Gompel, Jamie, Couldwell, William T , Gompel, Jamie J. Van , Group, the Unmatched Applicants Study

Journal of the American College of Surgeons | December 17, 2025 | Volume: 242 | Issue: 6 | Pages: 1517-1528

10.1097/xcs.0000000000001737 Get It

BACKGROUND: Increasing interest in neurosurgery residency has led to a growing number of unmatched applicants, who often struggle to find appropriate guidance for their next steps. The authors examined trends, opinions, and options available to unmatched neurosurgery residency reapplicants. STUDY DESIGN: Demographic data of US applicants from MD programs obtained from the National Resident Matching Program (2009 to 2024) were analyzed using 1-way ANOVA analysis of time-interval averages. Opinions about reapplicants were assessed via an online survey of national neurosurgery leaders, including residency program directors and chairpersons (N = 356). RESULTS: All application trends showed greater change over time; however, the rate of accepted reapplicants showed no significant change among early (2009 to 2013: 4.8 ± 1.8), mid (2014 to 2018: 7.6 ± 4.8), and recent periods (2019 to 2024: 9.8 ± 2.5; p = 0.068). The survey had a 23.0% response rate (82 of 356). Commonly indicated reasons for failure to match included poor interview skills, weak recommendation letters, and personality issues. Although most survey respondents supported candidates reapplying, dual applications (applying to more than 1 specialty) were not widely encouraged. For those reapplying, pursuing a preliminary general surgery or research fellowship, obtaining new letters of recommendation from new subinternships, and publishing higher-quality research were the most endorsed uses of time before reapplying. However, most programs reported interviewing reapplicants sometimes to rarely and matching a reapplicant rarely to never. CONCLUSIONS: The number of reapplicants successfully matching into neurosurgery has not changed significantly during the past 15 years. Surveys indicate that leaders view reapplicants unfavorably, despite reapplicants’ efforts to improve their applications. These results suggest that neurosurgery mentors may do a disservice to potential reapplicants based on how residency program leadership considers reapplications. Candid guidance is needed for reapplicants in the residency matching process.
Static Versus Expandable Cages in Minimally Invasive Lateral Lumbar Interbody Fusion
Beyer, Ryan S. , Shooshani, Tara , Batista, Bianca, Fraipont, Genevieve , Pooladzandi, Omead , Pennington, Zach , Pham, Martin H. , Pennington, Zach , Fraipont, Genevieve M , Batista, Bianca, Brown, Nolan J.

Clinical Spine Surgery | November 18, 2024 | Volume: 38 | Issue: 7 | Pages: 326-332

10.1097/bsd.0000000000001737 Get It

Study Design: A meta-analysis approach to a systematic review. Objective: Perform a systematic review to identify all reports directly comparing outcomes of lateral lumbar interbody fusion (LLIF) using static versus expandable interbody cages. Specifically focusing on periprocedural complications, intraoperative morbidity, and fusion outcomes. Summary of Background Data: Minimally invasive surgical techniques, particularly LLIF, have gained popularity for their potential to reduce muscle and soft tissue dissection, leading to faster postoperative recovery. LLIF has been associated with fewer complications compared with open posterior approaches. The introduction of expandable lumbar interbody devices aims to further reduce surgical difficulty and potential complications. However, concerns include a small graft window due to the expansion mechanism and higher costs. Methods: The Web of Science, Scopus, and PubMed databases were systematically queried in accordance with PRISMA guidelines to identify articles comparing outcomes following LLIF using static and expandable interbodies. The Newcastle-Ottawa Scale (NOS) was employed to assess the risk of bias (ROB) in the selected studies. Extracted data underwent effect-size meta-analysis with the PyMARE library, using P<0.05 to define statistical significance. Results: Of the 77 identified articles, 4 studies comprising 283 patients (mean age: 67.1 y, 55.8% female) met the inclusion and exclusion criteria. A total of 150 patients (53%) were treated with static interbodies compared with 133 (47%) receiving expandable interbodies. The groups did not differ significantly with respect to operative time (P=0.59), blood loss (P=0.89), length of stay (P=0.78), subsidence (P=0.49), 24-month mean disc height (P=0.11), 24-month mean ODI (P=0.58), or 24-month mean visual analog scale (VAS) back pain (P=0.81). The expandable group saw a trend toward improved fusion rates (97% vs. 92%, P=0.06). Conclusions: The present meta-analysis suggests the use of expandable (vs. static) interbodies in LLIF surgery may result in similar surgical morbidity, subsidence, and decompression. Further prospective comparative studies are merited to validate these results.
Diagnosis and Management of Thoracolumbar Spinal Disorders Presenting as Cardiac, Gastrointestinal, and Other False Pain Syndromes
Brown, Nolan J. , Kuo, Cathleen C. , Pennington, Zach , Choi, Ashley E. , Chan, Andrew K. , Bui, Nicholas, Pham, Martin H. , Oh, Michael , Pennington, Zach , Zhang, Angie , Shahrestani, Shane , Hatter, Matthew J. , Camino-Willhuber, Gaston O

Clinical Spine Surgery | October 25, 2024 | Volume: 38 | Issue: 3 | Pages: 114-122

10.1097/bsd.0000000000001644 Get It

Summary of Background Data: Although pseudoangina is most commonly caused by cervical disc herniation, several cases have been described where thoracic herniation produced symptoms of pseudoangina. If thoracic herniation can produce angina-like pain, then it is important to consider whether pathology of the thoracolumbar spine, in general, can trigger false pain syndromes distinct from pseudoangina. Objective: We seek to provide the most comprehensive study regarding the diagnosis and treatment of spinal conditions causing false pain syndromes. Study Design: Systematic review of the current literature using PRISMA 2020 recommendations. Methods: We queried the literature and systematically selected relevant studies according to PRISMA guidelines. Results: Across 22 selected studies, the sample size was 30 patients, and a total of 26 met the criteria for statistical analysis. Seven (26.9%) of these patients presented with a chief complaint of pseudoangina resulting from thoracic disc herniation. 73.1% (19/26) of patients exhibited pain mimicking visceral origin. Overall, 13/19 (68.4%) patients exhibited thoracic spine disease only and 4/19 (21.1%) patients were affected at lumbar levels only, while 2 (10.5%) patients exhibited thoracolumbar herniation. Presentations included abdominal pain (11/19) mimicking appendicitis or pancreatitis, flank pain mimicking renal colic (8/19), and 2 cases of scrotal pain/orchalgia. Symptom durations ranged from acute (<24 h) to 7 years. Treatments were reported for 18/19 patients and all treated patients reported alleviated pain. Seven out of 18 patients were managed conservatively while 11/18 were treated surgically. Misdiagnosis resulted in unnecessary surgery (pancreaticojejunostomy) or other invasive procedures. Conclusions: In spinal disorders manifesting with atypical pain syndromes, delay in proper diagnosis and unnecessary treatments can, unfortunately, cause prolonged patient suffering and increased cost of health care. As a result, some have proposed that spinal screening should be incorporated into clinical examinations involving false pain syndromes.
Effect of the administration route on the hemostatic efficacy of tranexamic acid in patients undergoing short-segment posterior lumbar interbody fusion: a systematic review and meta-analysis
Hatter, Matthew J. , Hsu, Timothy I. , Shooshani, Tara , Yale, Olivia S., Pooladzandi, Omead , Solomon, Sean S. , Picton, Bryce , Ramanis, Marlena , Hashmi, Sohaib , Lee, Yu-Po , Pham, Martin H. , Pennington, Zach , Brown, Nolan J. , Bhatia, Nitin Narain

Journal of Neurosurgery: Spine | May 18, 2024 | Volume: 41 | Issue: 2 | Pages: 224-235

10.3171/2024.2.spine23779 Get It

OBJECTIVE Tranexamic acid (TXA) is an FDA-approved antifibrinolytic that is seeing increased popularity in spine surgery owing to its ability to reduce intraoperative blood loss (IOBL) and allogeneic transfusion requirements. The present study aimed to summarize the current literature on these formulations in the context of short-segment instrumented lumbar fusion including ≥ 1-level posterior lumbar interbody fusion (PLIF). METHODS The PubMed, Cochrane, and Web of Science databases were queried for all full-text English studies evaluating the use of topical TXA (tTXA), systemic TXA (sTXA), or combined tTXA+sTXA in patients undergoing PLIF. The primary endpoints of interest were operative time, IOBL, and total blood loss (TBL); secondary endpoints included venous thromboembolic complication occurrence, and allogeneic and autologous transfusion requirements. Outcomes were compared using random effects. Comparisons were made between the following treatment groups: sTXA, tTXA, and sTXA+tTXA. Given that sTXA is arguably the standard of care in the literature (i.e., the most common route of administration that to this point has been studied the most), the authors compared sTXA versus tTXA and sTXA versus sTXA+tTXA. Study heterogeneity was assessed with the I2 test, and grouped analysis using the Hedge’s g test was performed for measurement of effect size. RESULTS Forty-five articles were identified, of which 17 met the criteria for inclusion with an aggregate of 1008 patients. TXA regimens included sTXA only, tTXA only, and various combinations of sTXA and tTXA. There were no significant differences in operative time, TBL, or postoperative drainage between the sTXA and tTXA groups or between the sTXA and sTXA+tTXA groups. CONCLUSIONS The present meta-analysis suggested clinical equipoise between isolated sTXA, isolated tTXA, and combinatorial tTXA+sTXA formulations as hemostatic adjuvants/neoadjuvants in short-segment fusion including ≥ 1-level PLIF. Given the theoretically lower venous thromboembolism risk associated with tTXA, additional investigations using large cohorts comparing these two formulations within the posterior fusion population are merited. Although TXA has been shown to be effective, there are insufficient data to support topical or systemic administration as superior within the open PLIF population.
Oblique anterior column realignment with a mini-open posterior column osteotomy for minimally invasive adult spinal deformity correction: illustrative case
Pennington, Zach , Brown, Nolan J. , Pishva, Seyedamirhossein , Pham, Martin H. , Pennington, Zach , González, Hernán F. J.

Journal of Neurosurgery: Case Lessons | March 11, 2024 | Volume: 7 | Issue: 11 | Pages: No page available

10.3171/case23680 Get It

BACKGROUND Adult spinal deformity (ASD) occurs from progressive anterior column collapse due to disc space desiccation, compression fractures, and autofusion across disc spaces. Anterior column realignment (ACR) is increasingly recognized as a powerful tool to address ASD by progressively lengthening the anterior column through the release of the anterior longitudinal ligament during lateral interbody approaches. Here, we describe the application of minimally invasive ACR through an oblique antepsoas corridor for deformity correction in a patient with adult degenerative scoliosis and significant sagittal imbalance. OBSERVATIONS A 65-year-old female with a prior history of L4–5 transforaminal lumbar interbody fusion and morbid obesity presented with refractory, severe low-back and lower-extremity pain. Preoperative radiographs showed significant sagittal imbalance. Computed tomography showed a healed L4–5 fusion and a vacuum disc at L3–4 and L5–S1, whereas magnetic resonance imaging was notable for central canal stenosis at L3–4. The patient was treated with a first-stage L5–S1 lateral anterior lumbar interbody fusion with oblique L2–4 ACR. The second-stage posterior approach consisted of a robot-guided minimally invasive T10–ilium posterior instrumented fusion with a mini-open L2–4 posterior column osteotomy (PCO). Postoperative radiographs showed the restoration of her sagittal balance. There were no complications. LESSONS Oblique ACR is a powerful minimally invasive tool for sagittal plane correction. When combined with a mini-open PCO, substantial segmental lordosis can be achieved while eliminating the need for multilevel PCO or invasive three-column osteotomies.
Techniques for restoring optimal spinal biomechanics to alleviate symptoms in Bertolotti syndrome: illustrative case
Brown, Nolan J. , Pennington, Zach , Shahin, Hania, Nguyen, Oanh , Pham, Martin H. , Pennington, Zach

Journal of Neurosurgery: Case Lessons | December 18, 2023 | Volume: 6 | Issue: 25 | Pages: No page available

10.3171/case23467 Get It

BACKGROUND Lumbosacral transitional vertebrae (LSTVs) are congenital anomalies that occur in the spinal segments of L5–S1. These vertebrae result from sacralization of the lowermost lumbar segment or lumbarization of the uppermost sacral segment. When the lowest lumbar vertebra fuses or forms a false joint with the sacrum (pseudoarticulation), it can cause pain and manifest clinically as Bertolotti syndrome. OBSERVATIONS A 36-year-old female presented with severe right-sided low-back pain. Computed tomography was unremarkable except for a right-sided Castellvi type IIA LSTV. The pain proved refractory to physical therapy and lumbar epidural spinal injections, but targeted steroid and bupivacaine injection of the pseudoarticulation led to 2 weeks of complete pain relief. She subsequently underwent minimally invasive resection of the pseudoarticulation, with immediate improvement in her low-back pain. The patient continued to be pain free at the 3-year follow-up. LESSONS LSTVs alter the biomechanics of the lumbosacral spine, which can lead to medically refractory mechanical pain requiring surgical intervention. Select patients with Bertolotti syndrome can benefit from operative management, including resection, fusion, or decompression of the pathologic joint.
Retrospective single-surgeon study of prone versus lateral robotic pedicle screw placement: a CT-based assessment of accuracy
Brown, Nolan J. , Pennington, Zach , Kuo, Cathleen C. , Gold, Justin , Diaz-Aguilar, Luis Daniel , Mehkri, Yusuf , Pham, Martin H. , Pennington, Zach , Shahrestani, Shane , Singh, Rohin , Gendreau, Julian

Journal of Neurosurgery: Spine | July 22, 2023 | Volume: 39 | Issue: 4 | Pages: 490-497

10.3171/2023.5.spine221296 Get It

OBJECTIVE Lateral lumbar interbody fusion including anterior-to-psoas oblique lumbar interbody fusion has conventionally relied on pedicle screw placement (PSP) for construct stabilization. Single-position surgery with lumbar interbody fusion in the lateral decubitus position with concomitant PSP has been associated with increased operative efficiency. What remains unclear is the accuracy of PSP with robotic guidance when compared with the more familiar prone patient positioning. The present study aimed to compare robot-assisted screw placement accuracy between patients with instrumentation placed in the prone and lateral positions. METHODS The authors identified all consecutive patients treated with interbody fusion and PSP in the prone or lateral position by a single surgeon between January 2019 and October 2022. All pedicle screws placed were analyzed using CT scans to determine appropriate positioning according to the Gertzbein-Robbins classification grading system (grade C or worse was considered as a radiographically significant breach). Multivariate logistic regression models were constructed to identify risk factors for the occurrence of a radiographically significant breach. RESULTS Eighty-nine consecutive patients (690 screws) were included, of whom 46 (477 screws) were treated in the prone position and 43 (213 screws) in the lateral decubitus position. There were fewer breaches in the prone (n = 13, 2.7%) than the lateral decubitus (n = 15, 7.0%) group (p = 0.012). Nine (1.9%) radiographically significant breaches occurred in the prone group compared with 10 (4.7%) in the lateral decubitus group (p = 0.019), for a prone versus lateral decubitus PSP accuracy rate of 98.1% versus 95.3%. There were no significant differences in BMI between prone versus lateral decubitus cohorts (30.1 vs 29.6) or patients with screw breach versus those without (31.2 vs 29.5). In multivariate models, the prone position was the only significant protective factor for screw accuracy; no other significant risk factors for screw breach were identified. CONCLUSIONS The present data suggest that pedicle screws placed with robotic assistance have higher placement accuracy in the prone position. Further studies will be needed to validate the accuracy of PSP in the lateral position as single-position surgery becomes more commonplace in the treatment of spinal disorders.
Robot-assisted percutaneous pedicle screw placement accuracy compared with alternative guidance in lateral single-position surgery: a systematic review and meta-analysis
Patel, Neal , Kuo, Cathleen C. , Pennington, Zach , Brown, Nolan J. , Boyett, Candler , Diaz-Aguilar, Luis Daniel , Pham, Martin H. , Pennington, Zach , Gendreau, Julian , Singh, Rohin , Shahrestani, Shane

Journal of Neurosurgery: Spine | June 24, 2023 | Volume: 39 | Issue: 4 | Pages: 443-451

10.3171/2023.3.spine2329 Get It

OBJECTIVE While single-position surgery (SPS) eliminates the need for patient repositioning, the placement of screws in the unconventional lateral position poses unique challenges related to asymmetry relative to the surgical table. Use of robotic guidance or intraoperative navigation can help to overcome this. The aim of this study was to compare the relative accuracies offered by these various navigation modalities for pedicle screws placed in lateral SPS. METHODS According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the PubMed/Medline, Embase, and Cochrane Library databases were queried for studies reporting pedicle screw placement accuracy using fluoroscopic, CT-navigated, O-arm, or robotic guidance in lateral SPS, and a systematic review and meta-analysis was performed. Included studies all compared evaluated screw placement accuracy in lateral SPS using a single navigation method. Quality assessment was performed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system; risk of bias was assessed using the Newcastle-Ottawa Scale and the Joanna Briggs Institute checklist. The primary outcome, rate of pedicle screw breach, was analyzed using random-effects meta-analysis. RESULTS Eleven studies were included comprising 548 patients who underwent the placement of instrumentation with 2488 screws. For the fluoroscopic, CT-navigated, O-arm, and robotic guidance cohorts, there were 3, 2, 3, and 3 studies, respectively. Breach rates by modality were as follows: fluoroscopic guidance (6.6%), CT navigation (4.7%), O-arm (3.9%), and robotic guidance (3.9%). Random-effects meta-analysis showed a significant difference between studies, with an overall breach rate of 4.9% (95% CI 3.1%–7.5%; p < 0.001); however, testing for subgroup differences failed to show a significant difference between guidance modalities (QM = 0.69, df = 3; p = 0.88). Heterogeneity between studies was significant (I2 = 79.0%, τ2 = 0.41, χ2 = 47.65, df = 10; p < 0.001). CONCLUSIONS Robotic guidance of screws is noninferior to alternative guidance modalities in lateral SPS; however, additional prospective studies directly comparing different guidance types are merited.
Robotics planning in minimally invasive surgery for adult degenerative scoliosis: illustrative case
Pennington, Zach , Brown, Nolan J. , Quadri, Saif S., Pishva, Seyedamirhossein , Kuo, Cathleen C. , Pham, Martin H. , Pennington, Zach

Journal of Neurosurgery: Case Lessons | March 6, 2023 | Volume: 5 | Issue: 10 | Pages: No page available

10.3171/case22520 Get It

BACKGROUND Minimally invasive surgical techniques are changing the landscape in adult spinal deformity (ASD) surgery, enabling surgical correction to be achievable in increasingly medically complex patients. Spinal robotics are one technology that have helped facilitate this. Here the authors present an illustrative case of the utility of robotics planning workflow for minimally invasive correction of ASD. OBSERVATIONS A 60-year-old female presented with persistent and debilitating low back and leg pain limiting her function and quality of life. Standing scoliosis radiographs demonstrated adult degenerative scoliosis (ADS), with a lumbar scoliosis of 53°, a pelvic incidence–lumbar lordosis mismatch of 44°, and pelvic tilt of 39°. Robotics planning software was utilized for preoperative planning of the multiple rod and 4-point pelvic fixation in the posterior construct. LESSONS To the authors’ knowledge, this is the first report detailing the use of spinal robotics for complex 11-level minimally invasive correction of ADS. Although additional experiences adapting spinal robotics to complex spinal deformities are necessary, the present case represents a proof-of-concept demonstrating the feasibility of applying this technology to minimally invasive correction of ASD.