J Hip Preserv Surg . 2020 Feb 24;7(1):14-21. doi: 10.1093/jhps/hnz067. eCollection 2020 Jan.

Alexander von Glinski, Emre Yilmaz, Ryan Goodmanson, Clifford Pierre, Sven Frieler, Andre Shaffer, Basem Ishak, Cara Beth Lee, Keith Mayo

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Abstract

The purpose of this study was to identify the 30 most cited articles on hip arthroscopy and discuss their influence on recent surgical treatment. Due to advancements in hip arthroscopy, there is a widening spectrum of diagnostic and treatment indications. The purpose of this study was to identify the 30 most cited articles on hip arthroscopy and discuss their influence on contemporary surgical treatment. The Thomson Reuters Web of Science was used to identify the 30 most cited studies on hip arthroscopy between 1900 and 2018. These 30 articles generated 6152 citations with an average of 205.07 citations per item. Number of citations ranged from 146 to 461. Twenty-five out of the 30 papers were clinical cohort studies with a level of evidence between III and IV, encompassing 4348 patients. Four studies were reviewed (one including a technical note) and one a case report. We were able to identify the 30 most cited articles in the field of hip arthroscopy. Most articles were reported in high-impact journals, but reported small sample sizes in a retrospective setting. Prospective multi-arm cohort trials or randomized clinical trials represent opportunities for future studies.

© The Author(s) 2020. Published by Oxford University Press.

Orthop Traumatol Surg Res . 2020 Jun 19;S1877-0568(20)30167-5. doi: 10.1016/j.otsr.2020.04.009. Online ahead of print.

Alexander von Glinsk, Sven Frieler, Ronen Blecher, Kajsa Mayo, Cara Beth Lee, Emre Yilmaz, Jens R Chapman, Rod J Oskouian, Shane Tubbs, Thomas A Schildhauer

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Abstract

Background: Increasing numbers of unstable pelvic ring fractures, due to the ongoing demographic change and improvements in the rescue of high-energy traumatic events, are challenging trauma and orthopedic surgeons. While initial installation of an external fixation device is often necessary, placement of iliac crest pins can be difficult due to the complex osteology of the ilium.

Hypothesis: We aim to analyze (1) the length, localization and angulation of the iliac pillar and (2) to define the dimensions of the surgical corridor for a better understanding of pin entry point and trajectory, thus preventing shortcomings in anterior external fixation of pelvic ring injuries.

Methods: Twenty hemipelvises from 10 fresh-frozen cadaveric torsos (3 female, 7 males; mean age 80.2 years) were harvested. The following measurements were taken with digital calipers: Location of the iliac pillar in relation to the anterior superior iliac spine and to the acetabulum roof, mean length and diameter of the iliac pillar, maximum diameter of the iliac pillar. In addition we measured the width of the different bone layers.

Results: The mean length of the hourglass shaped iliac pillar was 107.04mm with a mean width of 17.0mm (min. 15.1; max. 19.2). The mean distance to the anterior superior iliac spine was 69.00mm (min. 64.8; max. 73.4). The mean maximum width of the iliac pillar was 12.16mm (min. 9.4; max. 13.8). Caudally the line describing the iliac pillar intercepts the cranial acetabular rim at 12 o'clock. The smallest mean diameter of the cancellous bone was 7.5mm±2.0.

Conclusion: The iliac pillar is part of the complex osteology of the human pelvis. A cohesive description of its location and dimensions has been lacking. Successful treatment of pelvic fracture depends on an optimal preoperative planning, accurate overall reduction, and stable fixation. We described the origin and angulation to provide a good bone stock for external fixation pin and the width of the different bone layers. This study therefore contributes by facilitating a thorough understanding of pelvic osteology and describing the location and dimensions of an optimal osseous pathway.

Level of evidence: Anatomical descriptive study.

Keywords: Crest pin; External fixation; Iliac crest; Iliac pillar; Pelvic ring fractures.

Copyright © 2020 Elsevier Masson SAS. All rights reserved.

Eur Spine J . 2020 Jun 23. doi: 10.1007/s00586-020-06498-1. Online ahead of print.

Ronen Blecher, Emre Yilmaz, Basem Ishak, Alexander von Glinski, Marc Moisi, Rod J Oskouian, Joseph Dettori, Motti Kramer, Michael Drexler, Jens R Chapman

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Abstract

Background: Traumatic spinal injuries can be life-threatening conditions. Despite numerous epidemiological studies, reports on specific spinal regions affected are lacking.

Hypothesis: We hypothesized that fractures at specific regions, such as the cervical spine (including the axis segment), have been affected to a greater degree. We also hypothesized that advanced age may be a significant contributing factor.

Objective: To longitudinally analyze trend of spine fractures and specific fracture subtypes.

Study design: Longitudinal trend analysis of discharged patient state database.

Patient sample: Discharged patient's data from 15 years (2003-2017) METHODS: We retrieved pertinent ICD-9 and 10 codes depicting fractures involving the entire spine and specific subtypes. To assess possible association with age, we analyzed the trend of the average age in patients discharged with and without spinal fractures as well as in specific fracture subtypes. Similar analysis was performed for other common fragility fractures. FDA device/drug status: The manuscript submitted does not contain information about medical device(s) or drug(s).

Results: We found that within 15 years, the overall proportion of spinal fractures has increased by 64% (from 0.47 to 0.77% of all discharged patients) with the greatest increase noted in fractures of the cervical spine (123%) and specifically of the second cervical vertebra (84%). Age was found to have increased more in patients with spinal fractures than in the general discharged population. Surprisingly, other non-spinal fractures among patients above 60 remained relatively stable, demonstrating a spine-specific effect.

Conclusions: Our findings confirm a recent increase in all spinal fractures and in the cervical and sacral regions in particular. Advanced age may be an important underlying factor.

Keywords: Cervical spine; Epidemiology; Spinal fractures.

Clin Anat . 2020 Jul 6. doi: 10.1002/ca.23644. Online ahead of print.

Michael Snosek, Veronica Macchi, Carla Stecco, R S Tubbs, R DeCarro, Marios Loukas

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Abstract

Introduction: The alar fascia remains one of the most variably described fascial structure in the human body. Much disagreement persists in the literature and mainstream anatomical texts about its anatomy, function, and clinical significance. It is generally described as a coronally-oriented fascial sheet separating the retropharyngeal space anteriorly from the danger space posteriorly. The current study aimed to confirm the presence of the alar fascia and delineate its anatomical characteristics, connections, and potential function through gross dissection and microscopic analysis. Possible clinical and surgical implications are considered.

Methods: Twelve (12) cadaveric necks were dissected and examined histologically. Smooth muscle (αSMA), nerves (S100 protein), and myosin protein were identified immunohistologically to characterize the composition and possible functions of the alar fascia.

Results: The alar fascia was found in all specimens spanning between the carotid sheaths. Morphologically, it was not a delamination or derivative of the prevertebral fascia. It extended from the base of the skull to the upper thoracic level (T2) where it fused with the visceral fascia. No midsagittal connection was found between the alar and visceral fasciae. Immunohistochemically, the alar fascia was positive in focal areas for αSMA and S100 proteins but negative for fast and slow myosin.

Conclusion: The alar fascia is an independent and constant coronal fascial layer between the carotid sheaths. It contains neurovasculature and may limit the spread of retropharyngeal infections into the thorax as well as facilitate normal physiological functions of the cervical viscera. This article is protected by copyright. All rights reserved.

Keywords: alar fascia; danger space, retropharyngeal space; deep cervical fascia; histology of fascia; immunohistochemistry of fascia; prevertebral fascia; visceral fascia.

This article is protected by copyright. All rights reserved.

Clin Anat. 2020 Apr;33(3):355-364. doi: 10.1002/ca.23480. Epub 2019 Oct 14.

Boscolo-Berto R, Emmi A, Macchi V, Stecco C, Loukas M, Tubbs RS, Porzionato A, De Caro R.

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Abstract

Rachiotomy entails vertebral surgical incision, generally followed by exposure of the spinal cord, and is performed primarily for educational, research, or medicolegal purposes. Over time, several tools have been developed for this procedure, but Lodovico Brunetti designed the first effective prototypes in the mid-nineteenth century. To show the technical details of and the necessary maneuvers to be performed for Brunetti's rachiotomies to succeed, a computer-aided systematic literature review of online databases was performed to identify publications concerning Brunetti's chisels used for rachiotomy. Additional references from the studies and treatises included held in the Historical Section of the Medical Library at the University of Padova were checked manually for pertinent information. The known variants of Brunetti's chisels were reported in detail from the first to the third versions produced and intended for both posterior (first and third prototypes) and anterior (second prototype) vertebral dissection. Further evolution that led to the current commercialized model devoted to posterior use also was described. The models' strengths and weaknesses were assessed, as well as the nature of the changes Brunetti introduced over time and their motivation. In conclusion, these tools could represent an alternative to the use of electric saws, particularly for dissectors who prefer to have greater manual control in incising the vertebrae. Clin. Anat. 33:355-364, 2020.

© 2019 Wiley Periodicals, Inc.

KEYWORDS:

Brunetti; anatomy; cadaver dissection; chisel; history; laminectomy; rachiotomy; spinal cord

Clin Anat. 2020 Apr;33(3):332-337. doi: 10.1002/ca.23384. Epub 2019 Apr 25.

Kikuta S, Iwanaga J, Watanabe K, Kusukawa J, Tubbs RS.

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Abstract

The frontal nerve is the largest branch of the ophthalmic nerve. This nerve gives rise to two terminal branches, the supraorbital (SON) and supratrochlear nerves (STN). To the best of our knowledge, there are no reports describing the detailed proximal course of these nerves while inside the orbit. Therefore, the goal of this study was to clarify the anatomy of the SON and STN inside and at their exit from the orbit. Twenty sides from ten fresh-frozen cadavers were used in this study. Intra and extra orbital dissections were performed to observe the course of the SON and STN. Additionally, measurements of the nerves were made at these locations. The course of the SON and STN inside the orbit was classified into three groups depending on the STN branching pattern from the SON. The group without any branch from the SON and STN inside the orbit was the most common. The exit points of these nerves were via the supraorbital notch, foramen, or neither a notch nor foramen. A distinct fibrous band was consistently found tethering the nerve except in specimens with nerves traversing a bony foramen. The mean diameters of the SON and STN were 1.3 ± 0.2 and 0.7 ± 0.1 mm, respectively. The results of this study further our knowledge of the course and morphology of the SON and STN and might be useful for better understanding and potentially treating some forms of migraine headache due to SON or STN compression/entrapment. Clin. Anat. 33:332-337, 2020.

© 2019 Wiley Periodicals, Inc.

KEYWORDS:

anatomy; frontal nerve; migraine headache; supraorbital nerve; supratrochlear nerve

World Neurosurg. 2020 Apr;136:e608-e613. doi: 10.1016/j.wneu.2020.01.091. Epub 2020 Jan 23.

von Glinski A, Yilmaz E, Ishak B, Hayman E, Ramey W, Jack A, Iwanaga J, Oskouian RJ, Tubbs RS, Chapman JR.

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Abstract

BACKGROUND:

Iliac screws are a widely used sacropelvic fixation technique, which is often criticized for its impaired wound healing owing to hardware prominence. The aim of this study was to present a modified iliac screw (MIS) fixation technique that uses a different entry point more medially and caudally to the posterior superior iliac spine next to the rudimentary S1-S2 joint. Soft tissue coverage and midline distance in an MIS and a traditional iliac screw were compared.

METHODS:

Two different variations of iliac screws were placed into 12 fresh frozen adult cadavers (9 male, 3 female, mean age at death 77.08 years, mean body mass index 23.4). The distance between the midline and the center of the screw head was measured. We also compared the angulation of the trajectories. After wound closure, we measured the distance between the iliac screw head and the skin.

RESULTS:

The mean distance from the screw tulip head to the skin was 2.43 cm (range, 1.2-4.2 cm) with the traditional iliac screw and 3.16 cm (range, 1.7-4.3 cm) with the MIS. The mean distance to the midline with the MIS was 3.1 cm (range, 2.4-4.5 cm) lateral to the midline compared with the traditional iliac screw, of which the mean was 4.2 cm lateral to the midline (range, 3.7-4.9 cm). Mean angulation was 10°.

CONCLUSIONS:

The MIS avoids the use of connectors and provides less prominent pelvic fixation. Clinically, this might help prevent prominent hardware and related wound healing impairment.

Copyright © 2020 Elsevier Inc. All rights reserved.

KEYWORDS:

Iliac screws; Lumbar pelvic fixation; Modified iliac screw; Screw prominence; Soft tissue coverage

Injury. 2020 Mar 7. pii: S0020-1383(20)30148-0. doi: 10.1016/j.injury.2020.02.095. [Epub ahead of print]

Yilmaz E, von Glinski A, Schildhauer TA, Iwanaga J, Ishak B, Abdul-Jabbar A, Moisi M, Oskouian RJ, Tubbs RS, Chapman JR.

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Ann Anat. 2020 Mar;228:151439. doi: 10.1016/j.aanat.2019.151439. Epub 2019 Nov 11.

Haładaj R, Wysiadecki G, Tubbs RS, Topol M.

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Abstract

BACKGROUND:

The levator palpebrae superioris muscle (LPS) acts as the upper eyelid's major elevator and retractor and is innervated by the oculomotor nerve. The muscle's paralysis is manifested by ptosis.

MATERIAL AND METHODS:

70 orbits were dissected. After removing the orbital roof, the LPS' shape and anatomical variations (i.e., the presence of accessory muscular bands or atypical formation of the muscle) were assessed. To visualize the distribution of the oculomotor nerve's intramuscular sub-branches, the isolated levator palpebrae superioris muscles were stained using Sihler's staining technique.

RESULTS:

Several LPS anatomical variations were observed in the specimens examined, in seven of which (7/70; 10%) additional delicate muscular slips arose from the LPS' lateral border and reached the lacrimal gland. Histological examination confirmed the presence of striated skeletal muscle fibers in all those cases. In three other specimens (3/70; 4.28%), supernumerary muscular bands ("tensor trochleae") were found that linked the levator with the superior oblique muscle's trochlea. In the next case, the LPS' origin was double and the muscle was bipartite on its proximal half. In most cases (55/70; 78.6%), muscular branches formed a single bundle that wrapped around the superior rectus muscle's medial border to reach the levator's inferior surface. Intramuscular sub-branches were distributed largely within the proximal two-thirds of the LPS and formed an irregular, tree-like pattern. However, thin sub-branches and small retrograde sub-branches extended as far as the muscle's insertion.

CONCLUSIONS:

Plastic surgeons and ophthalmologists should be aware of the levator palpebrae superioris muscle's anatomic variations both in planning and conducting surgeries on the upper eyelid.

Copyright © 2019 Elsevier GmbH. All rights reserved.

KEYWORDS:

Anatomic variation; Innervation; Levator palpebrae superioris; Oculomotor nerve; Orbit; Sihler’s stain

Clin Anat. 2020 Mar;33(2):223-231. doi: 10.1002/ca.23456. Epub 2019 Sep 8.

Iwanaga J, Anand MK, Jain MN, Nagata M, Matsushita Y, Ibaragi S, Kusukawa J, Tubbs RS.

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Abstract

Our goal was to clarify the relationship between the superior wall of the mandibular canal and the presence of teeth. We also sought to study the structural changes of the mandibular canal after tooth loss. Twenty sides from 10 dry mandibles derived from six males and four females were used for this study. The age of the specimens at the time of death ranged from 57 to 91 years. The mandibles were cut in the midline resulting in 20 hemi-mandibles. The presence of teeth (from the second premolar to the third molar) was recorded for each hemi-mandible. The mandibular canal in the body of the mandible was divided into four areas, that is, Areas 1-4. The superior wall of the mandibular canal and a cancellous bone pattern above the mandibular canal were observed. Next, the mandibular canal was horizontally cut at its center and the superior wall of the mandibular canal observed inferiorly. A total of 75 areas (20 dentulous areas and 55 edentulous areas) were produced. The distal view was classified into three groups, Type I (trabecular pattern), Type II (osteoporotic pattern), and Type III (dense/irregular pattern). The Type I pattern was found in 60.0% (12/20) of the dentulous areas and 32.7% of the edentulous areas. While the Type II pattern was found in 15.0% (23/55) of the dentulous areas and 41.8% of the edentulous areas. The inferior view was classified into four groups depending on the surface of the superior wall of the mandibular canal, that is, Class I (trabecular pattern), Class II (osteoporotic pattern), Class III (dense/irregular pattern), and Class IV (smooth).The Class I pattern was seen most frequently (55.0%) in dentulous areas and the Class IV pattern (45.5%) most frequently in edentulous areas. Based on these results, we conclude that the superior wall of the mandibular canal could change following tooth loss. Clin. Anat. 33:223-231, 2020.

© 2019 Wiley Periodicals, Inc.

KEYWORDS:

anatomy; cadaver; dentistry; edentulous; implants; inferior alveolar nerve; mandible; mandibular canal; osteoporosis

Clin Anat. 2020 Mar;33(2):207-213. doi: 10.1002/ca.23454. Epub 2019 Sep 5.

Iwanaga J, Watanabe K, Anand MK, Tubbs RS.

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Abstract

Our goal was to evaluate a new air dissection technique for the spaces of the head and neck using fresh-frozen cadavers. Eight sides from four fresh-frozen Caucasian cadavers were used in this study. Compressed air was initially placed into the pterygomandibular space while simultaneously observing the spaces of the head and neck. Subsequently, the pterygomandibular space on the contralateral side of the specimen was insufflated and observations made. For these methods, simultaneous observation of mediastina and lungs was made using intrathoracic endoscopy. On all sides, the buccal, submental, sublingual, parotid, parapharyngeal, and retropharyngeal spaces were insufflated on both ipsilateral and contralateral sides. Deviation of the larynx and trachea was observed externally and deviation of the mediastinum and lungs via intrathoracic endoscopy. We introduced air dissection into spaces of the head and neck. This new technique might help students, teachers, dentists, medical doctors, and other healthcare providers to better understand the three-dimensional anatomy of the spaces of the head and neck and their communicating pathways. Clin. Anat. 33:207-213, 2020.

© 2019 Wiley Periodicals, Inc.

KEYWORDS:

air dissection; anatomy; cadaver; cancer; fasciae; head and neck; infection; maxillofacial; odontogenic infection; spaces

Clin Anat. 2020 Mar;33(2):232-236. doi: 10.1002/ca.23459. Epub 2019 Sep 8.

Nooma K, Saga T, Iwanaga J, Tabira Y, Watanabe K, Tubbs RS, Yamaki KI.

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Abstract

For various clinical/surgical procedures, it is important to accurately understand the location of the sinuatrial node (SAN). Therefore, this study's goal was to develop a new and simple method to visualize the SAN in human hearts. A total of 16 formalin-fixed human hearts were used in the study. After the epicardium was removed, the fat tissue on the myocardium's surface was brushed and removed in a solution of 40°C water with a surfactant to show the SAN's location. Once the structure considered to be the SAN was observed, histological observation was conducted with Masson's trichrome staining to confirm its identity. The working myocardium, SAN branch of the coronary artery, and the structure believed to be the SAN were observed in all specimens. Histological analysis confirmed this structure to be the SAN. We believe that the method described herein might contribute to a better understanding of the SAN's morphologic features and serve as an improved teaching aide. Clin. Anat. 33:232-236, 2020.

© 2019 Wiley Periodicals, Inc.

KEYWORDS:

anatomy; arrhythmias; cadaver; conduction system; heart; sinuatrial node; sulcus terminalis

Clin Anat. 2020 Mar;33(2):199-206. doi: 10.1002/ca.23442. Epub 2019 Aug 19.

Reina MA, Boezaart AP, Tubbs RS, Zasimovich Y, Fernández-Domínguez M, Fernández P, Sala-Blanch X.

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Abstract

The epineurium has been accepted as the outer anatomical barrier of the peripheral nerves. Our objective was to characterize the microanatomy of the layers surrounding nerves using different tissue-specific staining methods. Two hundred forty-two cross sections of human sciatic and median nerves, and brachial plexuses of eight fresh unembalmed cadavers, were examined. The samples were fixed in formaldehyde solution and stained with hematoxylin-eosin, Masson's trichrome, or epithelial membrane antigen under standard conditions. Because epithelial membrane antigen only stains the perineurium, we demonstrated using hematoxylin-eosin and Masson's trichrome that there were different collagen layers inside and outside the nerves. All fascicles had a collagen layer that surrounded the perineurium and were in close contact with it, with no adipose tissue between them. Unlike the perineurium, this layer, an "internal epineurium," contained no cells, and it surrounded one or a small group of fascicles. Bundling these fascicles or small groups of fascicles together was the true epineurium, and between the true and internal epineurium, we consistently found an adipose-containing compartment. More proximal to this, the tibial and common peroneal nerves were bundled together by another collagen layer, the circumneurium, which also had a fat-cell-containing compartment deep to it. There were scattered collagen fibers among the adipocytes. Using tissue-specific staining, we were able to demonstrate a collagen layer, the "internal epineurium." Outside the nerves, we identified several fat-containing concentric compartments. Those compartments were limited by collagen fiber layers that were also similar to the epineurium. Clin. Anat. 33:199-206, 2020.

© 2019 Wiley Periodicals, Inc.

KEYWORDS:

epineurium; fascicles; perineurium; peripheral nerve; regional anesthesia

Plast Reconstr Surg. 2020 Mar;145(3):524e-529e. doi: 10.1097/PRS.0000000000006558.

Kikuta S, Iwanaga J, Watanabe K, Kusukawa J, Tubbs RS.

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Abstract

BACKGROUND:

The depressor septi nasi is a facial muscle with many different descriptions of its anatomy. Therefore, the aim of this study was to clarify the relationship of the depressor septi nasi, incisivus labii superioris, and surrounding structures.

METHODS:

Twenty sides from 10 fresh-frozen cadaveric heads were used in this study. The depressor septi nasi and incisivus labii superioris were dissected intraorally and extraorally, and the relationship with surrounding structures was observed.

RESULTS:

Eighteen of 20 sides had a depressor septi nasi. When present, the depressor septi nasi originated from the orbicularis oris above the central incisor and the medial portion of the inferior part of the incisivus labii superioris and inserted into the base of the medial crus of the major alar cartilage and nasal septum. These three muscles were three-dimensionally fused at the insertion point of the depressor septi nasi. There was no specimen where the depressor septi nasi originated directly from the maxilla. The depressor septi nasi runs obliquely from the nasal septum and the base of the medial crus of the major alar cartilage to the orbicularis oris and inferior part of the incisivus labii superioris.

CONCLUSION:

A better understanding of the depressor septi nasi, incisivus labii superioris, and surrounding structures might be important during various surgical techniques, especially rhinoplasty.

Spine (Phila Pa 1976). 2020 Feb 21. doi: 10.1097/BRS.0000000000003443. [Epub ahead of print]

Elia C, Arvind V, Brazdzionis J, von Glinski A, Schell BA, Pierre CA, Ogunlade J, Chapman JR, Oskouian RJ.

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Abstract

STUDY DESIGN:

Nationwide Readmissions Database Study.

OBJECTIVE:

To investigate the patterns of readmissions and complications following hospitalization for elective single level anterior lumbobsacral interbody fusion.

SUMMARY OF BACKGROUND DATA:

Lumbar interbody spine fusions for degenerative disease have increased annually in the United States, including associated hospital costs. Anterior lumbar interbody fusions (ALIFs) have become popularized secondary to higher rates of fusion compared to posterior procedures, and preservation of posterior elements. Prior national databases have sought to study readmission rates with some limitations due to older diagnosis and procedure codes. The newer 2016 International Classification of Diseases Tenth Revision, Clinical Modification (ICD-10 CM) includes more specification of the surgical site.

METHODS:

We utilized the 2016 United States Nationwide Readmissions Database (NRD), this nationally representative, all-payer database that includes weighted probability sample of inpatient hospitalizations for all ages. We identified all adults (≥ 18 years) using the 2016 ICD-10 coding system who underwent elective primary L5-S1 ALIF and examined rates of readmissions within 90-days of discharge.

RESULTS:

Between January and September 2016, a total of 7,029 patients underwent elective stand-alone L5-S1 ALIF who were identified from NRD of which 497 (7.07%) were readmitted within 90-days of their procedure. No differences in gender was appreciated. Medicare patients had statistically significant higher readmission rates (47.69%) among all payer types. With respect to intraoperative complications, vascular complications had statistically significant increased odds of readmission (OR, 3.225, 95% CI, 0.59 - 1.75; p = 0.0001). Readmitted patients had higher total healthcare costs.

CONCLUSION:

An overall 90-day readmission of 7.07% following stand-alone single level lumbosacral (L5-S1) ALIF. ALIF procedures have increased in frequency, and an understanding of the comorbidities, age-related demographics, and costs associated with 90-day readmissions are critical. Surgeons should consider these risk factors in preoperative planning and optimization.

LEVEL OF EVIDENCE:

3.

Childs Nerv Syst. 2020 Feb;36(2):225-226. doi: 10.1007/s00381-018-3759-0. Epub 2018 Feb 24.

Vetter M, Oskouian RJ, Tubbs RS.

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Lymphat Res Biol. 2020 Feb;18(1):2-6. doi: 10.1089/lrb.2018.0079. Epub 2019 Aug 21.

Dupont G, Iwanaga J, Yilmaz E, Tubbs RS.

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Abstract

Alzheimer's disease (AD) is a complex neurodegenerative disorder causing progressive cognitive decline, memory loss, and death of neural tissue. Current research suggests a connection between bulk flow of interstitial fluid and cerebrospinal fluid across the blood-brain barrier and the recently confirmed meningeal lymphatic channels of the brain. The main symptom of interest in AD is the spontaneous aggregation of amyloid beta (Aβ) proteins resulting from increased production or lack of clearance from brain tissues. These protein aggregates manifest as plaques in the capillary and artery lumina and the neuronal and dural tissues of the brain, and are known to contribute to cerebral amyloid angiopathy and a host of other neuroinflammatory conditions. The meningeal lymphatics contain a substantial population of immune cells and also serve as a drain into the deep cervical lymph nodes. In this study we discuss the molecular mechanisms by which Aβ could gain access to meningeal lymphatic channels through the blood-brain interface, including ways in which it can be cleared to preclude aggregation and plaque deposition.

KEYWORDS:

Alzheimer's disease; amyloid beta; blood–brain interface; glymphatic system; meningeal lymphatics

World Neurosurg. 2020 Feb;134:e272-e276. doi: 10.1016/j.wneu.2019.10.040. Epub 2019 Oct 16.

von Glinski A, Elia C, Ansari D, Yilmaz E, Takayanagi A, Norvell DC, Pierre CA, Abdul-Jabbar A, Chapman JR, Oskouian RJ.

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Abstract

BACKGROUND:

Advancements in modern medicine have led to longer life expectancy. Literature on spinopelvic fixation in elderly patients is limited. We investigated morbidity and mortality in octogenarians who underwent spinopelvic fixation.

METHODS:

A retrospective chart review was conducted of patients who underwent spinopelvic fixation from January 2014 through December 2018 at a single institution. Patients were grouped into the octogenarian group (OG), 80-89 years old, and comparison group (CG), 40-50 years old. Demographics; pathology; Charlson Comorbidity Index; Hounsfield units; surgery details; and clinical data including complications, intensive care unit and length of hospital stay, and mortality were collected and compared.

RESULTS:

Inclusion criteria were met by 26 patients (OG: n = 14; CG: n = 12). Diagnoses in the OG were deformity (42.9%), pseudarthrosis (35.7%), fracture (7.1%), infection (7.1%), and tumor (7.1%). The only significant differences in baseline patient characteristics were that Charlson Comorbidity Index was significantly higher in the OG (6.0 ± 1.4) compared with the CG (1.1 ± 1.0) (P < 0.001) and the OG had lower Hounsfield units (P < 0.001), indicating poorer bone quality. More patients in the CG underwent staged and anterior approaches compared with the OG (P = 0.031). Major and minor complication rates were 57.1% and 42.9%, respectively, in the OG (P = 0.98) and 25% and 25% in the CG (P = 0.34). Mortality rate was 14.3%.

CONCLUSIONS:

With an aging population, the number of patients requiring spinopelvic fixation will continue to grow. Spine surgeons must carefully weigh benefits and risks in patients with multiple comorbidities.

Copyright © 2019 Elsevier Inc. All rights reserved.

KEYWORDS:

Lumbopelvic fixation; Morbidity; Mortality; Octogenarian; Spine surgery

World Neurosurg. 2020 Feb;134:e93-e97. doi: 10.1016/j.wneu.2019.09.090. Epub 2019 Sep 25.

von Glinski A, Yilmaz E, Ishak B, Ramey W, Jack A, Iwanaga J, Abdul-Jabbar A, Oskouian RJ, Tubbs RS, Chapman JR.

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Abstract

BACKGROUND:

This study describes a modified iliac screw technique and compares it with the traditional iliac screw in regard to neurovascular structures at risk. Few studies have detailed the insertion point's surrounding anatomy and its relationship to vulnerable neurovascular structures when this modified technique is used. Therefore we describe our modified iliac screw entry and trajectory and detail the surrounding anatomy and neurovascular structures at risk with this technique in comparison with the "gold standard" trajectory.

METHODS:

The traditional iliac screw (TS) and modified iliac screw (MS) were placed into 12 fresh-frozen adult cadavers (3 female, 9 male). We measured the screw-to-supragluteal artery, vein, and nerve (SGANV) bundle and screw-to-sciatic notch distances. Further, we dissected the medial cortical border of the iliac screw to identify its final position with respect to the surrounding anatomy.

RESULTS:

No medial or lateral cortical breaches were visualized after screw placement. The MS was 18.31 mm from the greater sciatic foramen compared with 18.65 mm with the TS. The smallest distance from the MS to the greater sciatic foramen was 13.9 mm compared with 14.8 mm with the TS, an insignificant difference. The SGANV bundle-to-MS distance was 20.6 mm, and SGANV bundle-to-TS distance was 20.77 mm, again an insignificant difference.

CONCLUSIONS:

Using the modified iliac screw technique does not change the intraosseous pathway (and thus bone purchase) with respect to the distance between the screw and neurovascular structures at risk.

Copyright © 2019 Elsevier Inc. All rights reserved.

KEYWORDS:

Iliac screws; Lumbopelvic fixation; Modified insertion point; Neurovascular injuries; Supragluteal artery

Neurosurg Rev. 2020 Jan 23. doi: 10.1007/s10143-020-01243-0. [Epub ahead of print]

Kolb B, Peterson C, Fadel H, Yilmaz E, Waife K, Tubbs RS, Rajah G, Walker B, Diaz V, Moisi M.

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Abstract

The lateral lumbar interbody fusion technique for lumbar arthrodesis is gaining popularity and being added as an option to traditional posterior and anterior approaches. In light of this, we analyzed the literature to identify the 25 most cited articles regarding lateral lumbar interbody fusion. The Thomson Reuters Web of Science was systematically searched to identify papers pertaining to lateral lumbar interbody fusion. The results were sorted in order to identify the top cited 25 articles. Statistical analysis was applied to determine metrics of interest, and observational studies were further classified. A search of all databases in the Thomson Reuters Web of Science identified 379 articles pertaining to lateral lumbar interbody fusion, with a total of 3800 citations. Of the 25 most cited articles, all were case series, reporting on a total of 2981 patients. These 25 articles were cited 2232 times in the literature and total citations per article ranged from 29 to 433. The oldest article was published in 2006, whereas the most recent article was published in 2015. The most cited article, by Ozgar et al., was cited 433 times, and the journal Spine published 7 of the 25 most cited articles. Herein, we report and analyze the 25 most cited articles on lateral lumbar interbody fusion, which include 25 cases series reporting a variety of data on a total of 2513 patients. Such data might assist in the design and interpretation of future studies pertaining to this topic.

KEYWORDS:

Citation analysis; Lateral; Lateral lumbar interbody fusion; Lumbar; Spine