Are the popliteofibular ligament, the arcuate ligament, and the fibular insertion of the popliteus muscle the same structure? An anatomic and terminological study.

Lesions in the lateral region of the knee can result in severe disability due to instability and articular degeneration. The structures in the posterolateral side of the knee function as a unit contributes to rotation and translation limits. Anatomical descriptions of the lateral corner of the knee are incomplete and contradictory. This study aims to verify, through anatomical dissections in cadavers, if the fibular insertion of the popliteus muscle, the arcuate ligament, and the popliteofibular ligament are distinct or the same structure with different terminology and descriptions in the literature. Fifteen cadavers were dissected. Photographs were taken, and in some cases, a video was recorded. Also, the correct terminology for ligament and insertion was searched. The dissections allowed the popliteus muscle to be identified proximally in the lateral femoral condyle, in the fibula head's posterolateral region, and through a meniscocapsular insertion. In none of the anatomy books reviewed, this fibular insertion of the popliteus muscle is mentioned. However, our findings and data from other experimental studies provide evidence of its presence. The aponeurotic portion of the arcuate ligament is distinguished from the short lateral ligament, which is the fibular insertion of the popliteus muscle with its tendinous attachment. Therefore, the term popliteofibular ligament should be abandoned based on the anatomic terminology, and the term "fibular insertion of the popliteus muscle" should be used instead.

Epidemiological evaluation of jaw cysts according to the new WHO classification: a 30-year retrospective analysis.

The aim of the present study was to analyze the epidemiology of maxillofacial odontogenic and non-odontogenic cysts diagnosed for 30 years in a Brazilian population. A retrospective descriptive cross-sectional study was performed. Biopsy records were obtained from the archives of a Brazilian referral center between 1989 and 2019. Data regarding age, gender, anatomical location, and histopathological diagnosis were collected and categorized. Further, a literature search for similar studies was performed. A total of 6.994 biopsy records were evaluated, but only 367 (5.24%) cases were classified as odontogenic cysts (OC) or non-odontogenic cysts (NOC). Among all cystic lesions, 341 cases (92.9%) were OC and 26 cases (7.1%) were NOC. These lesions were more common in females (n = 208 / 56.67%) and located mostly in the mandible (n = 195 / 53.1%). In patients with OC, the radicular cyst was the most frequent (n = 134 / 36.5%), followed by the dentigerous cyst (n = 101 / 27.5%) and the odontogenic keratocyst (n = 52 / 14.2%). Patients with NOC had a higher frequency of epidermoid cyst (n = 12 / 3.3%), oral lymphoepithelial cyst (n = 7 / 1.9%), and nasopalatine duct cyst (n = 4 / 1.1%). The OCs were more prevalent than NOCs, and inflammatory cysts were the most common among all the OCs.

Epidemiological evaluation of jaw cysts according to the new WHO classification: a 30-year retrospective analysis

Abstract: The aim of the present study was to analyze the epidemiology of maxillofacial odontogenic and non-odontogenic cysts diagnosed for 30 years in a Brazilian population. A retrospective descriptive cross-sectional study was performed. Biopsy records were obtained from the archives of a Brazilian referral center between 1989 and 2019. Data regarding age, gender, anatomical location, and histopathological diagnosis were collected and categorized. Further, a literature search for similar studies was performed. A total of 6.994 biopsy records were evaluated, but only 367 (5.24%) cases were classified as odontogenic cysts (OC) or non-odontogenic cysts (NOC). Among all cystic lesions, 341 cases (92.9%) were OC and 26 cases (7.1%) were NOC. These lesions were more common in females (n = 208 / 56.67%) and located mostly in the mandible (n = 195 / 53.1%). In patients with OC, the radicular cyst was the most frequent (n = 134 / 36.5%), followed by the dentigerous cyst (n = 101 / 27.5%) and the odontogenic keratocyst (n = 52 / 14.2%). Patients with NOC had a higher frequency of epidermoid cyst (n = 12 / 3.3%), oral lymphoepithelial cyst (n = 7 / 1.9%), and nasopalatine duct cyst (n = 4 / 1.1%). The OCs were more prevalent than NOCs, and inflammatory cysts were the most common among all the OCs.

An anatomic study of the iliotibial tract.

PURPOSE: To identify the structure of the iliotibial tract at knee level, as well as its insertions, layer arrangement, and relationship with other structures of the lateral region of the knee and to compare the findings with available literature. METHODS: Ten detailed anatomic dissections were performed by using incisions as recommended by the literature in fresh cadaver knees identifying the iliotibial tract components. RESULTS: The authors observed an iliotibial tract arrangement in superficial, deep, and capsular-osseous layers. Insertions have been described as follows: at linea aspera, at the upper border of the lateral epicondyle, at the patella, and at Gerdy's tibial tuberculum and across the capsular-osseous layer. CONCLUSIONS: The iliotibial tract (ITT) has important interconnections to the femur, the patella, and the lateral tibia; the iliopatellar band joins the ITT to the patella through the superficial oblique retinaculum and the lateral femoropatellar ligament, and the ITT capsular-osseous layer presents differentiated fibers in an arched arrangement that borders the femoral condyle and inserts laterally to the Gerdy's tubercle. CLINICAL RELEVANCE: The iliotibial tract can be considered as an anterolateral knee stabilizer, particularly its capsular-osseous layer, which, together with the anterior cruciate ligament, constitutes a functional unit forming a spatial "horseshoe" form. The detailed description of the structures forming iliotibial tract plays an important role in the study of knee instabilities. Its important tibial, femoral, and patellar connections are described so that better understanding of tibial femoral instability on the lateral side as well as patellofemoral instability can be achieved and mechanisms of repair can be conceived.

Estudo anatomico do trato iliotibial: revisão crítica de sua importância na estabilidade do joelho / Anatomic study of the iliotibial tract: critical revision of its importance for knee stability

Os autores realizaram 10 dissecões anatomicas pormenorizadas em joelhos de cadáveres a fresco identificando os componentes do trato iliotibial e observaram sua disposição em camadas superficial, profunda e cápsulo-ossea. Foram observadas também suas inserçäes na linha áspera, na margem superior do epicondilo lateral, na patela, no tubérculo de Gerdy e através da camada cápsulo-¢ssea. Ap¢s a descrição desses componentes, relacionando com a literatura, os autores estabeleceram a importância do trato iliotibial como estabilizador ântero-lateral do joelho, especialmente da camada cápsulo-ossea, que, juntamente com o ligamento cruzado anterior, constitui uma unidade funcional formando uma figura espacial em ferradura. Este estudo permitiu maior compreensão da estabilização ântero-lateral do joelho, a gênese do sinal do ressalto e a contenção lateral da patela.