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Minimally invasive transforaminal lumbar interbody fusion with percutaneous navigated guidewireless lumbosacral pedicle screw fixation

Kevin S. Chen and Paul Park

This video details the minimally invasive approach for treatment of a symptomatic Grade II lytic spondylolisthesis with high-grade foraminal stenosis. In this procedure, the use of a navigated, guidewireless technique for percutaneous pedicle screw placement at the lumbosacral junction is highlighted following initial decompression and transforaminal interbody fusion. Key steps of the procedure are delineated that include positioning, exposure, technique for interbody fusion, intraoperative image acquisition, and use of a concise 2-step process for navigated screw placement without using guidewires.

The video can be found here: https://youtu.be/2u6H4Pc_8To.

In Neurosurgical Focus Volume 41 (2016): Issue videosuppl1 (Jul 2016): Video Atlas - Lumbosacral and Sacropelvic Fixation Strategies

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Minimally invasive transforaminal lumbar interbody fusion with reduction of spondylolisthesis: technique and outcomes after a minimum of 2 years' follow-up

Paul Park and Kevin T. Foley

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is a relatively new surgical procedure that appears to minimize iatrogenic soft tissue and muscle injury. The authors describe a technique for MI-TLIF that permits the surgeon to reduce spondylolisthesis percutaneously. The results in 40 consecutive patients who underwent MI-TLIF for symptomatic spondylolisthesis utilizing this approach are reviewed. Thirty cases involved a degenerative spondylolisthesis while the remaining 10 were isthmic. The minimum follow-up was 24 months with a mean of 35 months. The mean preoperative Oswestry Disability Index score was 55, decreasing to a mean of 16 postoperatively. The mean leg and back pain visual analog scale scores were 65 and 52, respectively, improving to means of 8 and 15. Reduction of the spondylolisthesis was achieved in all cases, with a mean decrease in forward translation of 76%. The authors conclude that MI-TLIF for symptomatic spondylolisthesis appears to be an effective surgical option with results that compare favorably to open procedures.

In Neurosurgical Focus Volume 25 (2008): Issue 2 (Aug 2008): Contemporary Minimally Invasive Spine Surgery

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Heparin-induced thrombocytopenia presenting as unilateral lower limb paralysis following lumbar spine surgery: case report

Brandon W. Smith, Jacob R. Joseph, and Paul Park

Heparin-induced thrombocytopenia (HIT) is a state of thrombocytopenia with a paradoxically elevated thrombotic potential after exposure to heparin. Severe cases can present with multiorgan involvement with direct and secondary effects. Although HIT has been reported following other surgeries, to the authors’ knowledge there has not been a report of HIT after spinal surgery. The present case details the course of a patient who underwent elective lumbar surgery followed by delayed presentation of shortness of breath due to multiple pulmonary embolisms and right lower-extremity paralysis due to extensive iliofemoral clot burden with acute compartment syndrome. The patient was treated with intravenous argatroban for extensive thrombosis and also required open thrombectomy and fasciotomies for treatment of compartment syndrome. Although the patient eventually experienced motor recovery, residual sensory deficits persisted at last follow-up. In this report, the pathophysiology, clinical presentation, and treatment of HIT are reviewed.

In Journal of Neurosurgery: Spine Volume 26 (2017): Issue 5 (May 2017)

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Chyloretroperitoneum following anterior spinal deformity correction

Case report

Cheerag D. Upadhyaya, Paul Park, and Frank La Marca

✓ Chyloretroperitoneum is an uncommon complication following spinal surgery. The authors present the case of a patient in whom conservative treatment and initial surgical measures failed to relieve varied symptoms of postsurgical chyloretroperitoneum. Following attempts at conservative management, a peritoneal window was surgically created to divert lymphatic flow from the retroperitoneal space into the peritoneal space, where it was resorbed. This unique surgical technique provides yet another option in the treatment of refractory chyloretroperitoneum following anterior lumbar spinal surgery. The authors describe their technique and review retroperitoneal lymphatic anatomy along with similar case reports in the literature.

In Journal of Neurosurgery: Spine Volume 7: Issue 5 (Nov 2007)

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Introduction. Thoracolumbar anterior spine surgery: contemporary techniques and outcomes

Paul Park, Juan Uribe, Tokumi Kanemura, and Dean Chou

In Neurosurgical Focus Volume 49 (2020): Issue 3 (Sep 2020): Thoracolumbar Anterior Spine Surgery

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The genetics of ossification of the posterior longitudinal ligament

William R. Stetler Jr., Frank La Marca, and Paul Park

Object

Ossification of the posterior longitudinal ligament (OPLL) is a pathological process of ectopic calcification with a preponderance for the cervical spine. Epidemiological and familial studies have both indicated predisposition; however, the genetic inheritance pattern and responsible genes for OPLL are still uncertain. The aim of this study was to evaluate and summarize the current understanding of the genetics underlying OPLL.

Methods

The authors reviewed epidemiological and genetic studies surrounding OPLL, with a particular focus on inheritance patterns and potential genes responsible for OPLL, using a PubMed database literature search.

Results

Despite an unclear inheritance pattern, there appears to be a strong familial link in patients with OPLL. Examination of these patterns using linkage analysis has shown multiple candidate genes that could be responsible for the inheritance of OPLL. Genes for collagen, nucleotide pyrophosphatase, transforming growth factors, and the vitamin D receptor have all been implicated. Additionally, multiple cytokines and growth factors, including bone morphogenetic proteins as well as other proteins and interleukins involved in bone development, have been shown to be abnormally expressed in patients with OPLL. In addition, multiple mechanical and metabolic factors such as hyperinsulinemia and obesity have been shown to be linked to OPLL.

Conclusions

Ossification of the posterior longitudinal ligament has a complex inheritance pattern. It does not appear that OPLL follows a simple, single-gene Mendelian inheritance pattern. Development of OPLL is more likely multifactorial in nature and develops in patients with a genetic predisposition from a variety of different mutations in various genes on various chromosomes. Additionally, environmental factors and interaction by other pathological disease processes, such as obesity and diabetes mellitus, may play a role in the development of OPLL in susceptible individuals.

In Neurosurgical Focus Volume 30 (2011): Issue 3 (Mar 2011)

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Pathophysiology of adult tethered cord syndrome: review of the literature

William R. Stetler Jr., Paul Park, and Stephen Sullivan

Object

Tethering of the spinal cord has been a recognized cause of neurological symptoms in pediatric patients and is increasingly being recognized as a cause of symptoms in adults as well. The pathophysiology surrounding spinal cord tethering has begun to be understood in the pediatric population but is still unclear in adult patients.

Methods

Using a PubMed database literature search, the authors reviewed the pathology and pathophysiology surrounding the tethered spinal cord, focusing particularly on the pathophysiology of adult tethered cord syndrome (TCS).

Results

Experimental data obtained in pediatric patients at surgery and in animal models indicate that spinal cord tethering causes a reduction in spinal cord blood flow and dysfunction of neuronal mitochondrial terminal oxidase. Retrospective analyses of patients undergoing surgery for adult TCS show that many adults developed symptoms following an event that could stretch the spinal cord, while others did not. Many patients also were found to have structural lesions in addition to a tethered spinal cord at diagnosis.

Conclusions

Both adult and pediatric TCSs are likely the result of a relative lack of blood flow to the spinal cord, causing dysfunction in mitochondrial oxidative phosphorylation. The likely reason the syndrome present later and differently in adults is that a secondary threshold of tension or a cumulative effect of repetitive, transient tension is placed on the cord before symptoms are recognized.

In Neurosurgical Focus Volume 29 (2010): Issue 1 (Jul 2010)

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Use of 3D CT-based navigation in minimally invasive lateral lumbar interbody fusion

Jacob R. Joseph, Brandon W. Smith, Rakesh D. Patel, and Paul Park

OBJECTIVE

Lateral lumbar interbody fusion (LLIF) is an increasingly popular technique used to treat degenerative lumbar disease. The technique of using an intraoperative cone-beam CT (iCBCT) and an image-guided navigation system (IGNS) for LLIF cage placement has been previously described. However, other than a small feasibility study, there has been no clinical study evaluating its accuracy or safety. Therefore, the purpose of this study was to evaluate the accuracy and safety of image-guided spinal navigation in LLIF.

METHODS

An analysis of a prospectively acquired database was performed. Thirty-one consecutive patients were identified. Accuracy was initially determined by comparison of the planned trajectory of the IGNS with post–cage placement intraoperative fluoroscopy. Accuracy was subsequently confirmed by postprocedural CT and/or radiography. Cage placement was graded based on a previously described system separating the disc space into quarters.

RESULTS

The mean patient age was 63.9 years. A total of 66 spinal levels were treated, with a mean of 2.1 levels (range 1–4) treated per patient. Cage placement was noted to be accurate using IGNS in each case, as confirmed with intraoperative fluoroscopy and postoperative imaging. Sixty-four (97%) cages were placed within Quarters 1 to 2 or 2 to 3, indicating placement of the cage in the anterior or middle portions of the disc space. There were no instances of misguidance by IGNS. There was 1 significant approach-related complication (psoas muscle abscess) that required intervention, and 8 patients with transient, mild thigh paresthesias or weakness.

CONCLUSIONS

LLIF can be safely and accurately performed utilizing iCBCT and IGNS. Accuracy is acceptable for multilevel procedures.

In Journal of Neurosurgery: Spine Volume 25 (2016): Issue 3 (Sep 2016)

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Outcomes after surgery for spinal metastatic leiomyosarcoma

Clinical article

John E. Ziewacz, Darryl Lau, Frank La Marca, and Paul Park

Object

Leiomyosarcoma is a smooth-muscle sarcoma that rarely metastasizes to the spine. Its clinical course is variable, although patients with metastatic leiomyosarcoma can experience prolonged survival as compared with patients with more aggressive metastatic tumors. The authors report their single-institution experience in the surgical treatment of patients with leiomyosarcoma metastatic to the spine.

Methods

A retrospective review of the electronic medical records was performed to obtain details on clinical management and outcomes for patients who had undergone surgical intervention for metastatic leiomyosarcoma of the spine. The few articles available in the current literature on this topic were also analyzed.

Results

Eight patients with metastatic leiomyosarcoma of the spine underwent surgical management between 2005 and 2011. Six patients (75%) had improvement in their Nurick grade. Patients who had presented with pain as a primary symptom experienced significant relief. Five patients (63%) had lesion recurrence, and 4 underwent repeat surgery at a mean of 10.2 months after their initial surgery. The mean duration of survival was 11.7 months (range 3.3–23.0 months).

Conclusions

Leiomyosarcoma rarely metastasizes to the spine. However, surgical intervention can relieve pain and improve neurological function. Given the potential for prolonged survival, aggressive management should be considered in well-selected patients.

In Journal of Neurosurgery: Spine Volume 17 (2012): Issue 5 (Nov 2012)

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Independent predictors of survival and the impact of repeat surgery in patients undergoing surgical treatment of spinal metastasis

Clinical article

Darryl Lau, Matthew R. Leach, Frank La Marca, and Paul Park

Object

Surgery for spinal metastasis is considered palliative, and postoperative survival is often less than a year. Recurrence of metastatic lesions is quite common, and it remains unclear whether repeat surgery is effective. In this study, the authors assessed independent predictors for survival at 6 months, 1 year, and 2 years after surgery, and examined whether repeat surgery for recurrence of spinal metastasis influenced survival rates.

Methods

Retrospective review of the electronic medical records was performed to identify a consecutive population of adult patients who underwent surgery for spinal metastasis during the period 2005–2011. Utilizing a Cox proportional hazard regression model, the authors assessed independent predictors and risk factors for survival at 6 months, 1 year, and 2 years after surgery. In addition, the impact of repeat surgery on survival was specifically assessed via multivariable analysis.

Results

A total of 99 patients were included in the final analysis. The overall mean postoperative duration of survival was 9.6 months. In addition to previously identified predictors of survival (preoperative ambulation, Karnofsky Performance Status [KPS], radiotherapy, primary cancer type, presence of extraspinal metastasis, and number of spinal segments with metastasis), pain on presentation and body mass index (BMI) of 25–30 were both independently associated with survival. Patients with recurrence who underwent repeat surgery had longer mean survival times than patients with recurrence who did not undergo repeat surgery (19.6 months vs 12.8 months, respectively). Repeat surgery was also independently associated with higher survival rates on multivariate analysis. Follow-up KPS was significantly higher in patients who underwent repeat surgery as well.

Conclusions

In addition to confirming previously identified predictors of survival following surgery for spinal metastasis, the authors identified BMI and pain on presentation as independent predictors of survival. They also found that repeat surgery may be a viable option in patients with metastatic recurrence and may offer prolonged survival, likely due to improved functionality, mitigating complications associated with immobility.

In Journal of Neurosurgery: Spine Volume 17 (2012): Issue 6 (Dec 2012)