Separate muscle bundles of the flexor digitorum superficialis overlying the ulnar nerve.

BACKGROUND: The aim of this study was to elucidate the morphological charac-teristics of the muscle bundles of the flexor digitorum superficialis (FDS) attached to the intermuscular aponeurosis (IMA) and any related structure that could potentially compress the ulnar nerve. MATERIALS AND METHODS: Fifty embalmed limbs of 34 adult cadavers were studied. RESULTS: The FDS arose as multiple separate bundles from the IMA of the lateral surface of the flexor carpi ulnaris in 76% of specimens. Below their origin, these separate bundles became attached continuously as a single mass to form the muscle belly. There were 1, 2, 3, 4 and 5 arising FDS muscle bundles in 28%, 30%, 4%, 10% and 4% of specimens, respectively. The muscle bundles were attached either only superficially (24% of cases) or across the entire width (20% of cases) of the IMA. In 32% of the specimens, bundles arose from the IMA in a combined fashion, being attached to the IMA superficially, deep and across the entire structure. The muscle bundles that arose from the deep part or entire width of the IMA were in contact with the ulnar nerve in 52% of specimens. In 11 (22%) specimens, the deep borders of the lowest muscle bundles close to the ulnar nerve were composed of tendinous fibres that divided from the IMA of the lateral surface of the flexor carpi ulnaris. The distance from the medial epicondyle to the lowest point of the FDS arising from the IMA was 62.0 ± 19.7 mm. CONCLUSIONS: The thick tendinous deep border of the lowest muscle bundle of the FDS where it attaches to the IMA is a potential cause of ulnar nerve compression.

Long-term follow up on recurrence of 305 ameloblastoma cases.

The aim of this study was to determine the appropriate treatment for ameloblastoma by considering the factors associated with recurrence, and to make a quantitative prediction of the risk factors for recurrence. Data on age and gender distribution, location of the tumour, histopathological findings, treatment method, and whether or not patients had a preoperative biopsy confirmation report were collected in 305 cases (239 patients; M: 139, F: 100) of ameloblastoma diagnosed and treated in 1985-2002. After initial statistical evaluation (chi(2)-test and Fisher's exact test), logistic regression analysis was performed to check relative significance and predict recurrence. The disease-free survival function curves of the patients with or without recurrence were obtained by the Kaplan-Meier method and compared using univariate regression analysis. The correlation between recurrence and the treatment method or histopathological type was significant. The differences between the 'conservative' and 'resection with bone margin' and between the 'conservative' and 'segmental resection or maxillectomy' groups in terms of disease-free survival were highly significant. The difference between the 'resection with bone margin' and 'segmental resection or maxillectomy' groups was not significant. A resection with safety margin is the best method to treat most proven ameloblastomas, and conservative treatment is reasonable for patients in their first decade or with unicystic or plexiform ameloblastoma.

Topographical relationship of the facial and vestibulocochlear nerves in the subarachnoid space and internal auditory canal.

PURPOSE: Our purpose was to investigate the topographical relationship of the facial and vestibulocochlear nerves from the brain stem through the internal auditory canal. METHODS: We dissected 15 formalin-fixed cadaveric heads and performed MR examinations in 35 healthy subjects in order to examine the topographical relationship of the facial and vestibulocochlear nerves. The cadaveric dissections and the in vivo MR imaging findings were compared indirectly. RESULTS: The relationship between the facial and vestibulocochlear nerves showed some variation among individuals and according to the location of the nerves within the cisterns or canal. Near the brain stem, 53% of the vestibulocochlear nerves were partially segmented on MR images. The vestibulocochlear nerve was completely divided into separate nerves only in the most lateral portion of the canal, except in three cadaveric dissections, in which separation of the superior vestibular nerve was seen near the brain stem. The facial and cochlear nerves were of similar size on 36% of the MR images. The superior vestibular nerve was larger than the inferior vestibular nerve on 81% of the MR images. CONCLUSION: The appearance of the facial and vestibulocochlear nerves was variable but followed certain consistent patterns.

Surgical anatomy of the anterior ethmoidal canal in ethmoid roof.

OBJECTIVES/HYPOTHESIS: This study was undertaken to examine three main relationships. First, the distance and angle from the anterior ethmoidal canal to the limen nasi and the sill were measured. Second, the location of the anterior ethmoidal canal was examined in relation to the lamellas and the skull base. Third, the existence of bony defects in the canal and the course of the canal through the anterior cranial fossa were studied. STUDY DESIGN: This study employed both sagittal computed tomography and cadaver dissection. METHODS: Seventy sagittally divided heads from randomly chosen Korean adult cadavers were used. Sagittal computed tomography was performed on all specimens. Then they were meticulously dissected under a surgical microscope. RESULTS: The mean distance and angle between the limen nasi and the anterior ethmoidal canal were 49.0 mm and 54.5 degrees, respectively. The anterior ethmoidal canal was located between the second and third lamella in 61 of 70 cases. In 60 of 70 cases it was attached to the base of the skull, and in the remaining 10 cases it ran 2 to 3 mm below the skull base. When viewed from the superior side, the course of the anterior ethmoidal canal formed a diagonal line from the lateral to the medial side. Partial bony defects of the anterior ethmoidal canal were observed in eight cases, and complete bony defects in none. CONCLUSION: This study provides surgeons with a better understanding of the anatomy of the anterior ethmoidal canal.

Surgical anatomy of the natural ostium of the sphenoid sinus.

OBJECTIVES: This study was undertaken to measure the distance and the angle between the anterior part of nasal cavity and the natural ostium of the sphenoid sinus. The anatomical location of the natural ostium according to the direction of surgeon's operating view toward the anterior wall of the sphenoid sinus was also analyzed. STUDY DESIGN: This study used careful cadaver dissection under a surgical microscope. METHODS: One hundred sagittally sectioned adult cadaveric heads were used. We measured the distances and angles for identifying the natural ostium of the sphenoid sinus using several reference points such as the limen nasi, the sill, and the posteroinferior end of the superior turbinate. In addition, we tried to identify whether the location of the natural ostium is medial or lateral to the posterior end of the superior turbinate. RESULTS: The natural ostium of the sphenoid sinus was located at an angle of 35.9 degrees with a distance of 56.5 mm from limen nasi and at an angle of 34.3 degrees with a distance of 62.7 mm from nasal sill. It was located approximately 1 cm above the posteroinferior end of the superior turbinate and at a medial aspect to the posterior end of the superior turbinate in 83% of specimens. CONCLUSIONS: We speculate that the posteroinferior end of the superior turbinate is the best landmark for identifying the natural ostium of the sphenoid sinus. Furthermore, the natural ostium should ideally be searched from a superior and medial aspect in relation to the posteroinferior end of the superior turbinate.

Arterial supply of the nasal tip in Asians.

OBJECTIVES: The blood supply to the nasal tip and columella was examined to determine whether it could be damaged as a result of transcolumellar incision during an external rhinoplasty approach in Asians. METHODS: The blood vessels that supply the nasal tip were examined by dissecting 51 cadavers, and their corresponding 102 nasal sections were injected with red latex before dissection. The size and distribution of the vessels were measured with the unaided eye and the primary supply vessels were determined. The subdermal layer in which the vessels lie and the course of the vessels were also investigated. RESULTS: The main blood supply source of the nasal tip proved to be the lateral nasal artery in 78% (80/102) of the cases examined, while the remaining cases (22%) received their blood supply via the dorsal nasal artery. Columellar branches were narrow in diameter and varied in size and appearance, and were therefore appeared insufficient as a main blood supply. These arteries passed through the musculoaponeurotic layer, but they were also in close proximity to the main surgical plane in the dome of the lower lateral cartilage. CONCLUSIONS: The authors speculate that the nasal tip blood supply in Asians is primarily derived from the lateral nasal or dorsal nasal arteries, with a variable contribution from the columella arteries. Therefore, it is important to correctly determine the surgical plane below the musculoaponeurotic layer in order to prevent skin flap necrosis or nasal tip deformity that may occur from damage to the main vessel during an external rhinoplasty approach.

Surgical anatomy of the nasofrontal duct: anatomical and computed tomographic analysis.

OBJECTIVES: Although complete anatomical knowledge of the nasofrontal duct has been of great importance, little is known about it. The aim of this study is to examine the drainage site of the nasofrontal duct and to investigate the anatomical boundaries of the nasofrontal duct according to the drainage site. STUDY DESIGN: One hundred sagittally divided adult head specimens were analyzed by computed tomography and dissection under the surgical microscope. METHODS: Computed tomography scans of 50 adult cadaver heads were taken sagittally at 1-mm intervals and coronally at 3-mm intervals to find the nasofrontal duct. One hundred specimens, made up of sagittally divided adult cadaver heads, were dissected under the microscope to study the structure of the nasofrontal duct. RESULTS: We identified the anterior, posterior, medial, and lateral boundaries of the nasofrontal duct. In the most common type, the superior portion of the uncinate process formed the anterior border and the superior portion of the bulla ethmoidalis formed the posterior border of the nasofrontal duct. The conchal plate formed the medial border and the suprainfundibular plate formed the lateral border of the nasofrontal duct. Other variations are described in detail. CONCLUSIONS: To widen the nasofrontal communication, removing the upper portion of the ground lamella of the ethmoid bulla, which is the posterior boundary of the nasofrontal duct, with cutting forceps seems to be a safe and easy method.

Computed tomographic and anatomical analysis of the basal lamellas in the ethmoid sinus.

OBJECTIVES: To investigate the exact anatomical structure of the lamellas in the ethmoid sinus by computed tomography (CT) and anatomical analysis. STUDY DESIGN: Cadaver dissections and CT scans were used to compare lamellar structures and their radiological images. METHODS: Anatomical microdissection of 100 midsagittal sections from adult cadaver head specimens were examined and compared with those of sagittal CT scans at 1-mm intervals. RESULTS: The posteroinferior end of the uncinate process attaching to the inferior turbinate divided the fontanelle into the anterior and posterior portions in the majority of cases. The basal lamellas of the bulla ethmoidalis were subdivided into three major types. The posteroinferior portion of its basal lamella was connected to the lower horizontal portion of the third basal lamella in all cases. The anterior indentation of the third lamella was identified in nine cases, but there was no indentation in the posterior direction. The basal lamella of the superior turbinate was attached to the skull base superiorly either separately or fused to the third lamella, and its posteroinferior portion was attached to the lowest portion of the anterior wall of the sphenoid sinus. The supreme turbinate existed in 50 cases; however, its basal lamella was identified in only 15 cases. CONCLUSIONS: Our results indicate that the lamellas of the ethmoid sinus have relatively uniform patterns, although there is variability in shape. It is hoped that this study will provide surgeons with a more detailed structure of the basal lamellas for better surgical results and lower complication rates.

Fontanelle and uncinate process in the lateral wall of the human nasal cavity.

OBJECTIVES: Although a complete anatomic knowledge of the fontanelle is a prerequisite to perform a surgical antrostomy opening, little is known about the boundary, shape, and size of the fontanelle. The purpose of this paper is to determine the best site for maintaining the patency of a surgical antrostomy opening by defining the anatomic boundaries, shape, and size of the fontanelle as well as its histological structure. MATERIALS AND METHODS: One hundred sagittally divided heads were utilized. Mucosa overlying the lateral nasal wall was carefully removed with an operating microscope under 6x magnification. In some cases, a double mucous membrane, including the posteroinferior portion of the uncinate process, was cut as a whole and embedded in paraffin. The sections were stained with H&E. RESULTS: The boundary of the fontanelle and the location of the natural ostium were described in detail. Eight patterns of the posteroinferior portion of the uncinate process were observed. There were three major fontanelle shapes when observed from the medial aspect to the lateral: triangular, pencil-like, and oval. The triangular type was the most common. The anterior portion of the fontanelle was shorter than the posterior when observed medially and was wider than the posterior portion when observed inferiorly. CONCLUSIONS: The anterior portion of the fontanelle is more prone to stenosis than the posterior portion. An antrostomy in the posterior fontanelle may be more ideal for a middle meatal antrostomy of the maxillary sinus.

Morphometric study of the pedicles of thoracic and lumbar vertebrae in Koreans.

STUDY DESIGN: The shape and size of the pedicles of the human spine differs within different races. The authors studied the diameters and angles of the spine pedicle from the T1 to L5 levels in Koreans. The following measurements were made 1) transverse diameter, 2) superoinferior diameter, 3) anteroposterior pedicle angle, 4) horizontal pedicle angle, and 5) pedicle axis angle. OBJECTIVES: This study obtained indices of pedicle morphology in Koreans to use in transpedicular screw fixation and to explain the difference between other races and Koreans. SUMMARY OF BACKGROUND DATA: Internal fixators for vertebrae fixation have been developed. Knowledge of pedicle morphology is essential for pedicle screw use. The use of pedicle screws in Asians is questionable. Few reports exist regarding pedicle morphology, and in those few reports, the pedicle isthmus diameter, pedicle angles, and the depth to the anterior cortex are emphasized. METHODS: The following measurements of the diameter and length of the human cadaver pedicle were done with vernier and dial calipers: 1) transverse diameter of pedicles, 2) superoinferior diameter of pedicles, 3) anteroposterior pedicle angle, and 4) horizontal pedicle and pedicle axis angles. RESULTS: The widest transverse diameter of the pedicle was seen at the L5 level and the narrowest was at the T4 level. The widest superoinferior diameter of the pedicle was seen at the T12 level, the narrowest was at the T1 level. In the transverse plane, the angles of the pedicles of T11 and T12 were faced laterally. The anteroposterior angle increased rapidly at the T4 level, with the T1 level having the greatest. In the sagittal plane, the horizontal angle of the lumbar vertebra was almost parallel to the horizontal plane. The pedicle axis was longest at the L3 level and shortest at the T1 level. In all areas, the transverse diameter of the pedicle in males was wider than the that in the female. CONCLUSIONS: The results suggest that using 6-mm screws can violate the cortex of the pedicles in a significant number of levels of the upper lumbar spine. Using a screw longer than 40 mm is dangerous in the lower thoracic spine of a Korean. A statistical difference exists between the transverse diameter of the pedicles of Westerners and Koreans.

Morphometric study of the lumbar spinal canal in the Korean population.

STUDY DESIGN: The anatomic dimensions of the vertebral body and spinal canal of the lumbar spine were analyzed in Koreans. OBJECTIVES: To determine the normal dimension of the lumbar spinal canal in Koreans, to determine whether there are any racial differences in the morphometry of the lumbar spinal canal, and to provide criteria for diagnosing spinal stenosis in the Far Eastern Asian. SUMMARY OF BACKGROUND DATA: Some radiologic and anatomic studies have been conducted regarding the size of the lumbar spinal canal of whites and blacks in western and African countries. METHODS: One-thousand-eight-hundred measurements were performed on the transverse and sagittal diameters of vertebral bodies and spinal canals using complete sets of 90 lumbar vertebrae. RESULTS: The mean mid-sagittal diameter of the lumbar spinal canal in the Korean population was less than that measured in white and African populations, but there was no significant differences between the Korean, white, and African populations regarding the transverse diameter of the lumbar spinal canal. CONCLUSION: The mid-sagittal diameter of the lumbar spinal canal is narrowest in the Far Eastern Asian population; the radiologic criteria of spinal stenosis should be reconsidered for these people.

Variability of the surgical anatomy of the neurovascular complex of the cerebellopontine angle.

The variability of the anatomic relationship of the anterior inferior cerebellar artery (AICA) to the facial (seventh) and vestibulocochlear (eighth) nerves was studied in 52 cerebellopontine angles (CPAs) from 26 adult cadavers. The AICA originated from the basilar artery (98.1%) or from the vertebral artery (1.9%) as a single (92.3% of CPAs) or duplicate (7.7%) artery. Each of the 52 CPAs had one or more arterial trunks that coursed in close proximity to the seventh and eighth cranial nerves and thus were said to be nerve-related. The nerve-related arterial trunks were divided into three segments based on their relationship to the nerves and meatus: the premeatal, meatal, and postmeatal segments. The nerve-related branches of the AICA gave rise to the internal auditory artery in 92.3% of the CPAs, the recurrent perforating artery in 78.8%, and the subarcuate artery in 30.8%. The importance of understanding the surgical anatomy of the neurovascular complex of the CPA when performing a vestibular neurectomy is reviewed.

Mid-sagittal canal diameter and vertebral body/canal ratio of the cervical spine in Koreans.

In order to ascertain the normal values of the mid-sagittal canal diameter and the canal/body ratio of the cervical spine in Korean adults, ninety sets of cervical vertebral columns were examined. The average mid-sagittal canal diameters from C3 through C7 in the normal Korean are 13.2 +/- 1.3 millimeters in male and 13.1 +/- 2.6 millimeters in female. The normal average canal/body ratio of the cervical spine is 0.93 +/- 0.10 in male and 1.02 +/- 0.09 in female. The mid-sagittal canal diameter is largest in the White population and smallest in Asian, but there is no racial differences in the canal/body ratio, and the lower limit of normal canal/body ratio is 0.8 in Korean. The authors conclude that measurement of the canal/body ratio is more reliable than direct measuring of the mid-sagittal diameter of the cervical spinal canal in the diagnosis of cervical spinal stenosis or predicting the prognosis of cervical spinal cord injury.

Topographical anatomy of the fibula and peroneal artery in Koreans.

Vascularized fibula flaps have many advantages in the restoration of the contour and function of the mandible. Potential disadvantages include, unreliable skin paddle and the limited volume of the fibula. This study was designed, to clarify the anatomy of the peroneal artery to the fibula and lateral leg skin, and to measure the dimensions of the fibula available for dental implant placement in Korean. Through the dissection of 63 legs of Korean cadavers, we demonstrated that in most cases the musculoperiosteal (mp) and septocutaneous (sc) branches of the peroneal artery were distributed at the middle and lower thirds of the fibula. There were double the number of mp perforators to the skin compared to sc branches. This indicates the inclusion of a generous > 1 cm cuff of Peroneous longus and flexor hallucis longus (FHL) in the distal and middle third of the fibula. The location of the nutrient foramen was just proximal to the midpoint. Thus, a 15-20 cm length of the fibula is available in Koreans and an 8 12 mm length of implant can be placed to the fibula, which provides sufficient bone to reconstruct a large mandibular defect.

Branching patterns and symmetry of the course of the facial artery in Koreans.

The topography and the course of the facial artery were investigated in 47 Korean cadavers. The final branch of the facial artery was the lateral nasal branch in 44.0% whereas it was the angular branch in 36.3% of the cases. In 54.5% of the cases, the facial artery ended symmetrically. According to previous studies, variations in the distribution pattern of the facial artery have been regarded as racial difference. However, in this study we showed that the diverse pattern of the facial artery distribution demonstrates individual variation rather than racial difference. The superior and inferior labial arteries on the right side were more dominant than those on the left. The average distance between the branching points for the inferior alar branch and for the lateral nasal branch was 15.9 mm, and it was 25.2 mm between the points for the superior labial branch and for the inferior alar branch. The branching point of the inferior labial branch was 30.9 mm apart on average from that of the superior labial branch. The courses of the facial arteries showed no significant differences based on either laterality or gender.

Anterior clinoid process and optic strut in Koreans.

The anterior clinoid process and the optic strut are often removed during operation on the anterior part of the cavernous sinus. Therefore it is important for neurosurgeons to verify their dimensions and variations. The purpose of this study was to investigate the dimension and the variation of the anterior clinoid process and to describe the locational variation of the optic strut. Seventy-three skulls of Korean adults were used. The average length, basal width and thickness of the anterior clinoid process were 9.18 +/- 1.55, 9.63 +/- 1.49 and 5.32 +/- 1.07 mm, respectively. The average thickness of the optic strut was 2.9 +/- 1.15 mm and it was commonly attached to anterior two-fifths of the anterior clinoid process. The complete caroticoclinoid canal was observed in 4.1%, however it was incomplete in 11.6%. The incidence of a caroticoclinoid canal in Koreans was relatively low compared with other races.

Correlation between the postmortem stature and the dried limb-bone lengths of Korean adult males.

The postmortem stature was measured in 57 Korean adult males (age range: 20-86 years old, mean: 52.3 years old) in supine position. After dissection of the corpses, we measured the maximum length of the remaining limb-bones (humerus, radius, ulna, femur, tibia and fibula). The correlation coefficients between the stature and each limb-bone length were calculated. Simple regression equations for estimating stature from each limb-bone length and multiple regression equations from the combination of limb-bone lengths were also obtained.

Mandibular anatomy related to sagittal split ramus osteotomy in Koreans.

Sagittal split ramus osteotomy (SSRO) is one of the surgical techniques used to correct mandibular deformities. In order to prevent many surgical anatomical problems, we observed the anatomical structures related to SSRO. In dry mandibles of Koreans, lingular tips were located somewhat posteriorly and superiorly on the mandibular ramus. On the coronal sections of mandible, the mean cortical width of facial cortex was increased toward the ramus region while the lingual cortex was thinnest in the ramus region. On the same sections, all the fusion points of the buccal and lingual cortical plate were located above the mandibular lingula and beneath the mandibular notch. So, performing the SSRO on Koreans, medial horizontal osteotomy should be done through the superior aspect of the mandibular lingula. The cut line is extended 5-8 mm posterior to the mandibular lingula to preserve sufficient cortical width to strengthen the involved osseous segments and reduce possible surgical complications.

Emerging patterns of the cervical cutaneous nerves in Asians.

Numerous reports exist upon clinical viewpoints of the four cervical cutaneous nerves. Unfortunately, a detailed description of the cervical cutaneous nerves has not yet been published. For this reason, administering effective anaesthesia to a particular nerve branch is difficult. The aim of this study was to clarify the anatomical knowledge about the emerging patterns of the cervical cutaneous nerves in the superficial neck using 35 Korean cadavers (22 male, 13 female). Four cervical cutaneous nerve branches penetrating the fascia of the posterior border of the sternocleidomastoid muscle (SCM) were classified into seven types based on the locations of their nerve emergence. Among these, the separated type (L-G-T-S) was the most frequent (50%). followed by the L-G x T-S type (20.3%), in which the great auricular nerve (G) and the transverse cervical nerve (T) emerged at the same level on the posterior SCM border.

Synthesis and in vitro antibacterial activity of quaternary ammonium cephalosporin derivatives bearing oxazolidinone moiety.

Several oxazolidinones having amine moiety were prepared to form a quaternary ammonium salt with cephalosporin nucleus, and antibacterial activity of the quaternary ammonium cephalosporin derivatives bearing oxazolidinone moiety were examined particularly with expectation of dual activity. However, the cephalosporin-oxazolidinone compounds revealed rather weaker antibacterial activity in vitro than their parent oxazolidinone and cephalosporin without showing any characteristic activity as expected.