Morphological characteristics of the Lisfranc ligament.

BACKGROUND: This study aimed to clarify the morphological characteristics of the Lisfranc ligament and the cuneiform 1-metatarsal 2&3 plantar ligament (CMPL). METHODS: Forty legs from 20 cadavers were examined. Classification proceeded according to the number of fiber bundles in the Lisfranc ligament and the CMPL. Morphological features measured were fiber bundle length, width, thickness, and angle. RESULTS: In Type I-a, the Lisfranc ligament and the CMPL were a single fiber bundle; in Type I-b, the Lisfranc ligament was a single fiber bundle, and the CMPL was two fiber bundles; in Type II-a, the Lisfranc ligament was a two fiber bundle, and the CMPL was a single fiber bundle; in Type II-b, the Lisfranc ligament and the CMPL were two fiber bundles; in Type III-a, the Lisfranc ligament was three fiber bundles, and the CMPL was a single fiber bundle; in Type III-b, the Lisfranc ligament was three fiber bundles, and the CMPL was two fiber bundles; in Type IV, the Lisfranc ligament and the CMPL could not be separated. Type I-a was seen in 37.5%, Type I-b in 10%, Type II-a in 30%, Type II-b in 7.5%, Type III-a in 7.5%, Type III-b in 2.5%, and Type IV in 5%. The Lisfranc ligament was significantly larger than the CMPL in total fiber bundle width, total fiber bundle thickness, and total fiber bundle angle. CONCLUSION: The Lisfranc ligament had up to 3 fiber bundles and the CMPL had one or two fiber bundles; classifications were four types and two subgroups.

Morphological features of the posterior oblique ligament of the ulnar collateral ligament of the elbow joint.

PURPOSE: The purpose of this basic research study was to clarify the morphological characteristics of the posterior oblique fibers (POL) of the ulnar collateral ligament using a large number of specimens. METHODS: This study examined 50 arms from 25 Japanese cadavers. Type classification was performed by focusing on the positional relationship between POL morphology and the joint capsule. The morphological features measured were fiber bundle length, width, and thickness. RESULTS: The POL was classified as follows: Type I, the POL's anterior and posterior edges are located on the surface of the joint capsule and can be separated as a single fiber bundle; Type II-a, the POL anterior edge can be separated, but the posterior edge cannot be separated; Type II-b, the POL posterior edge can be separated, but the anterior edge cannot be separated; and Type III, the POL cannot be separated from the joint capsule. Type I was seen in 23 elbows (46%), Type II-a in 6 elbows (12%), Type II-b in 7 elbows (14%), and Type III in 14 elbows (28%). CONCLUSION: The results of this study suggested that the POL could be classified into an independent type and an unclear type, and the presence of the unclear type was one of the factors that caused morphological variation.

Morphological features of the deep component of the posterior inferior tibiofibular ligament.

PURPOSE: The deep component of the posterior inferior tibiofibular ligament (PITFL) was classified by type in this large-scale cadaveric study to provide basic information that will help elucidate the mechanisms underlying ankle joint posterior impingement syndrome. METHODS: This investigation examined 100 legs from 49 Japanese cadavers (mean age at death, 79 ± 11 years; 58 sides from men, 42 from women). In classification, absence of an independent fiber of the deep component of the PITFL were classified as Type I, an independent fiber of the deep component of the PITFL was classified as Type II-a, an independent fiber of the deep component of the PITFL with bundles of fibers connected to the posterior intermalleolar ligament (PIML) was classified as Type II-b, and an independent fiber of the deep component of PITFL with a band shape connected to the PIML was classified as Type III. RESULTS: A deep component of the PITFL was present in all specimens. An independent fiber of the deep component of the PITFL was present in 37 legs (37%), connecting to the deep component of the PITFL and PIML in 26 (70.3%). Several types of deep component of the PITFL were identified: Type I in 63 legs (63%); Type II-a in 11 (11%); Type IIb in 12 (12%); and Type III in 14 (14%). No significant differences were seen between the right and left legs. Type I male were significantly more than Type I female (p < 0.05). Type III female were significantly more than Type III male (p < 0.05). CONCLUSIONS: Strong relationships exist between the PITFL and PIML.

Morphological features of the cervical ligament.

PURPOSE: The purpose of this study was to clarify the morphological characteristics of the cervical ligament (CL). METHODS: This study examined 80 legs from 40 Japanese cadavers. The CL was classified by the number of fiber bundles. The morphological features measured were fiber bundle length, width, thickness, and angle with the sagittal plane. RESULTS: The CL was classified as follows: Type I, the CL is a single fiber; Type II, the CL consists of a superficial fiber and an inferior fiber; and Type III, the CL consists of a superficial fiber, intermediate fiber, and inferior fiber. Type I was seen in 15 feet, Type II in 57 feet, and Type III in 8 feet. In comparisons of morphological features within each type, significant differences were seen in fiber bundle length, width, and angle between superior fiber bundles and inferior fiber bundles of Type II and Type III. In comparison among types, the total fiber bundle width was significantly wider in Type II and Type III than in Type I, and the angle was significantly smaller in Type III than in Type I. CONCLUSION: The results of this study suggested that each type may have different sub-talar joint control functions.

Morphological features of the posterior intermalleolar ligament.

PURPOSE: In the present study, the posterior intermalleolar ligament (PIML) was classified by type using large-scale cadavers to provide basic information to help elucidate the mechanism of ankle joint posterior impingement syndrome. METHODS: This investigation examined 100 legs from 49 Japanese cadavers (mean age at death, 79 ± 11 years; 58 sides from men, 42 from women). In the classification method, an absent PIML was classified as Type I, a PIML with one fiber bundle (attachment to one place) was Type II, a PIML with two fiber bundles (attachment to two places) was Type III, and a PIML with three fiber bundles (attachment to three or more places) was Type IV. Furthermore, according to other adhering tissues, they were further subdivided and classified by type. RESULTS: There were various types of PIML: 19 (19%) Type I; 24 (24%) Type II; 23 (23%) Type III; and 34 (34%) Type IV. A PIML was present in 81 legs (81%). There were no significant differences between men and women and between left and right sides. CONCLUSIONS: The complex relationships of the PIML with the surrounding ligaments and tissues are considered to be among the factors that make interpretation of imaging findings difficult.

Morphological features of the inferior fascicle of the anterior inferior tibiofibular ligament.

In this study, the inferior fascicle of the anterior inferior tibiofibular ligament (AITFL) was classified to provide basic information to help elucidate the mechanism of ankle joint anterolateral impingement, and the morphological features of each type were compared for the purpose of clarification. This investigation examined 100 feet from 52 cadavers. The AITFL was classified into four types according to the presence or absence of the inferior fascicle and the positional relationship between the AITFL and the inferior fascicle of the AITFL. The morphological features of the AITFL that were measured included the fibre bundle length, fibre bundle width, fibre bundle angle, and the distance between the joint levels. A distinct, independent inferior fascicle of the AITFL was identified in 15 feet (15%). There were no significant differences in the morphological features based on differences in the AITFL classification. Therefore, these findings suggest that the presence or absence of the inferior fascicle and the difference in the positional relationship between the AITFL and the inferior fascicle of the AITFL are less likely to be involved in impingement during ankle dorsiflexion.

Morphological features of the bifurcated ligament.

INTRODUCTION: Damage to the bifurcate ligament is one of the most difficult injuries to diagnose from imaging techniques. A probable reason for this is that the morphological characteristics of this structure have yet to be sufficiently elucidated. We, therefore, endeavored to elucidate the morphological characteristics of the bifurcate ligament through a large-scale study involving numerous specimens. MATERIALS AND METHODS: This study included 100 feet from 52 formalin-fixed cadavers. The bifurcate ligament was classified into three types: presence of both calcaneonavicular ligament and calcaneocuboid ligament (Type I); absence of calcaneocuboid ligament (Type II); and absence of calcaneonavicular ligament (Type III). Morphological characteristics of the bifurcate ligament were determined by measuring fiber bundle length, width, and thickness at the center of each ligament. RESULTS: This classification resulted in 68 Type I feet (68%), 32 Type II feet (32%), and 0 Type III feet (0%). The calcaneonavicular ligament was 20.8 ± 2.9 mm long, 4.9 ± 1.2 mm wide, and 3.8 ± 1.1 mm thick. The calcaneocuboid ligament was approximately 10.5 ± 2.7 mm long, 4.7 ± 2.4 mm wide, and 1.5 ± 0.6 mm thick. The bifurcate ligament was located deep under the extensor hallucis brevis and extensor digitorum brevis muscles in all specimens. The calcaneal origin of the calcaneonavicular ligament was situated deep under the interosseous talocalcaneal ligament in all specimens. Two sides were identified in which the calcaneocuboid ligament was located deep under the dorsal calcaneocuboid ligament. CONCLUSION: Such variations and positional relationships were suggested to be factors complicating the diagnostic imaging of bifurcate ligament injuries. The present study results will likely form useful basic data for diagnostic imaging.

Splenic hemangiosarcoma with sinus endothelial differentiation.

A case of primary splenic hemangiosarcoma where the tumors entirely replaced the spleen is reported. Histologically, the splenic tumors consisted of two major components: (i) solid and nodular areas, in which spindle cells (SC) were arranged in interlacing fascicles; and (ii) vasoformative areas, in which vascular lining cells (VC) closely resembled normal splenic sinus endothelial cells (SSEC) in shape. Both SC and VC were immunoreactive with the markers of vascular endothelial cells (EC) including SSEC, JC70, von Willebrand factor, OKM5, vimentin MAb and Ulex europaeus-1 lectin. The tumor cells were positive for OKM5 MAb as well as normal SSEC and sheathed arterial EC, but other vascular EC in normal spleen were negative. Enzyme-histochemically, the tumor cells and normal SSEC revealed naphthol AS-D acetate esterase activity but no reaction for ALPase, whereas normal vascular EC other than SSEC in the spleen were positive for the latter but negative for the former. These studies revealed that the tumor cells expressed the same phenotype as normal SSEC. To the present author's knowledge this is the first report demonstrating sinus endothelial differentiation of splenic hemangiosarcoma, enzyme- and immuno-histochemically.

Cardiac rhabdomyoma. A case report with reference to atrial natriuretic peptide.

An autopsy case of cardiac rhabdomyoma in a male infant is reported. Many nodules of rhabdomyoma were present in all four cardiac chambers and were microscopically composed of ovoid, glycogen-laden cells and typical "spider cells". Atrial natriuretic peptide (ANP) was immunohistochemically demonstrated in both normal myocytes and rhabdomyoma cells of both atria, but not in normal myocytes and rhabdomyoma cells of both ventricles. Ultrastructurally, atrial specific granules were present in atrial rhabdomyoma cells and normal atrial cardiocytes, and these showed ANP immunoreactivity with protein A-gold technique. It could be said that the localization and intracellular distribution of ANP in this cardiac rhabdomyoma were closely similar to those of normal human heart. With regard to the presence of ANP, cardiac rhabdomyoma cells arising in atria seemed to differ from those in ventricles, although many tumor nodules occurred in both atria and ventricles. Furthermore, it seemed that cardiac rhabdomyomas could also be divided into two parts: 1) an atrial part with ANP, and 2) a ventricular part without ANP. Therefore, this study confirms the hypothesis that cardiac rhabdomyoma is a hamartoma rather than a true neoplasm.

Immunohistochemical demonstration of peptide YY in gastrointestinal endocrine tumors.

Fourteen cases of gastrointestinal endocrine tumors were examined immunohistochemically for peptide YY, pancreatic polypeptide, glucagon, and somatostatin. Peptide YY cells were present in seven tumors, pancreatic polypeptide cells in eight tumors, glucagon cells in six tumors, and somatostatin cells in nine tumors. All 7 rectal endocrine tumors examined were found to contain peptide YY, while in the tumors of the other sites peptide YY cells were not detected. Peptide YY cell population in the rectal tumors was small to moderate in comparison with pancreatic polypeptide and glucagon cell population. This study suggests that peptide YY cells may be a common constituent of rectal endocrine tumors together with pancreatic polypeptide and glucagon cells, and that the peptide YY spectrum of gastrointestinal endocrine tumors may be closely related to the location of the tumors. Moreover, it can also be said that peptide YY may be used as one of the markers of rectal endocrine tumors.