Medicine and Health Sciences Commons^™

Bilateral Sternocleidomastoid Variant With Six Distinct Insertions Along The Superior Nuchal Line., Graham Dupont, Joe Iwanaga, Juan J Altafulla, Stefan Lachkar, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

Anatomical variations of the sternocleidomastoid muscle (SCM) have been observed to occupy multiple origins and insertion points and have supernumerary heads, sometimes varying in thickness. During routine dissection, a SCM was observed to have six distinct insertions that interface with the course of the superior nuchal line, ending at the midline, bilaterally. This variation was also seen to receive innervation from the accessory nerve as well as the great auricular nerve. To our knowledge, this variant of supernumerary insertions and nerve innervations has not yet been reported. These variants may pose as problematic during surgical approaches to the upper neck …

Radial Artery Injury With Attempted Intravenous Catheterization On The Dorsal Hand: A Case Report., Yusuf Alimi, Joe Iwanaga, Rod J Oskouian, Marios Loukas, R Shane Tubbs

Articles, Abstracts, and Reports

Intravenous (IV) access on the dorsum of the hand is of high clinical significance. As it is possible for an arterial injury during IV access on the dorsum of the hand to occur, clinicians and healthcare providers should be cognizant of regional anatomy and anatomical variations during IV placement so as to prevent injuries to the radial artery. We report a case of an injury to the radial artery with an attempted hand IV placement in a cadaver and suggest possible ways to prevent this complication.

A Variant Of The Sciatic Nerve And Its Clinical Implications., Graham Dupont, Florence Unno, Joe Iwanaga, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

Variants of gluteal neural anatomy are important to consider, especially during surgical approaches to the hip. During the routine dissection of the gluteal region, a variant of the sciatic nerve was found where the nerve left the pelvis fully split into its tibial and common fibular components. Intrapelvically and extrapelvically, there was no splitting of the two components by the piriformis muscle. Distally, the two parts of the nerve were draped over the medial and lateral edges of the ischial tuberosity. To avoid iatrogenic injury to the sciatic nerve during invasive or surgical approaches to this region, all possible anatomical …

Variant Distal Ulnar Nerve Loop: A Previously Undescribed Anatomical Finding., Mayank Patel, Joe Iwanaga, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

A previously undescribed variant ulnar nerve loop was discovered during the routine anatomic forearm and hand dissection of an adult female. The major finding was that of a large loop traveling around the distal tendon of the flexor carpi ulnaris. The variation presented here appears to be unique. The exact function of such derailed anatomy is not clear but, if found during surgery, might confound normal dissection methods or, when present, could result in varied clinical presentations regarding the sensory or motor examination of the hand.

Injury Of The Radial Nerve In The Arm: A Review., Taroob J Latef, Muhammad Bilal, Marc Vetter, Joe Iwanaga, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

Compression of the radial nerve is most commonly described at the supinator muscle (i.e., arcade of Frohse). However, radial nerve compression can occur in the arm. Therefore, the purpose of this article is to review both etiologies of radial nerve entrapment and the sites at which this can occur in the arm. The clinical presentation of radial nerve entrapment in the arm and how it differs from that of entrapment at other sites is reviewed and the conditions potentially predisposing to nerve entrapment are described. Particular attention is paid to the nerve's course and potential variants of the anatomical structures …

Anatomical Study Of The Extreme Lateral Transpsoas Lumbar Interbody Fusion With Application To Minimizing Injury To The Kidney., Joe Iwanaga, Emre Yilmaz, Tamir Tawfik, Amir Abdul-Jabbar, Marc Vetter, Marc Moisi, Koichi Watanabe, Koh-Ichi Yamaki, R Shane Tubbs, Rod J Oskouian

Articles, Abstracts, and Reports

Objective Since the extreme lateral lumbar interbody fusion procedure was first reported by Ozgur in 2006, a large number of clinical studies have been published. Anatomical studies which explore methods to avoid visceral structures, such as the kidney, with this approach have not been examined in detail. We dissected the retroperitoneal space to analyze how the extreme lateral transpsoas approach to the lumbar spine could damage the kidney and related structures. Methods Eight sides from four fresh Caucasian cadavers were used for this study. The latissimus dorsi muscle and the thoracolumbar fascia were dissected to open the retroperitoneum. The fat …

Piercing Of The Lumbocostal Ligament By The Subcostal Nerve: A Previously Unreported Case., Marc Vetter, Joe Iwanaga, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

As lateral approaches gain popularity in lumbar spine surgery, detailed discussions regarding anatomical variations in the innervation of the thoracolumbar region are of increasing importance. Damage to intercostal or subcostal nerves can lead to post-operative complications including regional loss of sensitivity, motor function, or abdominal wall hernias. More specifically, the subcostal nerve has been identified in the literature as one of the more vulnerable structures during such procedures. A clear understanding of the position of the subcostal nerve relative to nearby anatomical structures is therefore important for medical professionals. We herein report a rare anatomical variation in which the subcostal …

Hematoma In The Bucco-Mandibular Space: First Case Report., Joe Iwanaga, Charlotte Wilson, Emre Yilmaz, Cameron K Schmidt, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

Our previous studies based on intraoral dissection of fresh cadavers revealed that the fissure and loose connective tissues deep to the mucosa between the incisivus labii inferioris muscle and buccinator muscle form the entrance of the newly discovered bucco-mandibular space. To support the clinical significance of this space, we report the finding of a hematoma within this space in an adult fresh cadaver. Such a finding lends credence to studying the bucco-mandibular space and might help better understand the spread of some infections in the oral region.

Cadaveric Study For Intraoral Needle Access To The Infratemporal Fossa: Application To Posterior Superior Alveolar Nerve Block Technique., Joe Iwanaga, Emily Simonds, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

The posterior superior alveolar (PSA) nerve block is, from an anatomical perspective, challenging because the mandibular ramus and the zygomatic process of the maxilla can interfere with the course of the needle. Dentists empirically know that shifting the patient's mandible to the ipsilateral side can improve visibility and accessibility for such blocks. This cadaveric study aimed to establish anatomical evidence for the ipsilateral mandible shifting used in the PSA. The distance between the lateral most bulging point of the alveolar part of the maxilla and ipsilateral anterior border of the ramus of the mandible ranged from 1.4 to 6.9 mm …

Variant Prevertebral Muscle: Unique Cadaveric Findings., Jocelyn R Gonzales, Joe Iwanaga, Rod J Oskouian, R Shane Tubbs

Articles, Abstracts, and Reports

The levator scapulae muscle typically runs from the transverse process of the atlas to the superior angle of the scapula. In this paper, we describe a rare finding identified during a dissection of a male cadaver, wherein a continuation of the right levator scapulae ran past its normal attachment to the C1 transverse process, fusing with the inferior attachment of the rectus capitis lateralis muscle. No variants were found on the opposite side, and the innervation of the levator scapulae muscle variant was typical of that of a normal levator scapulae. We also describe other related variants of the cranial …

Undetected Small Accessory Mental Foramina Using Cone-Beam Computed Tomography., Joe Iwanaga, Koichi Watanabe, Tsuyoshi Saga, Shogo Kikuta, Yoko Tabira, Sadaharu Kitashima, Christian Fisahn, Fernando Alonso, R Shane Tubbs, Jingo Kusukawa, Koh-Ichi Yamaki

Articles, Abstracts, and Reports

INTRODUCTION: The accessory foramina could not be identified on some imaging modalities such as surface-rendered images. The purpose of this study was to investigate the ability of surface-rendered images in detecting these foramina.

MATERIALS AND METHODS: We analyzed 20 accessory mental foramina (AMF) in nine mandibles removed from cadavers with cone-beam computed tomography (CBCT) and assessed in surface-rendered images. All AMF were divided into three groups depending on their visibility.

RESULTS: Group 1 included AMF that were clearly visible as foramina, Group 2 were not clearly visible but could be recognized with concave parts, and Group 3 were not visible …