The position and morphometry of the fovea capitis femoris in computed tomography of the hip

Morphometry and Morphology of the Fovea Capitis of the Femoral Head and its Associated Implications

BACKGROUND AND OBJECTIVE

The fovea capitis, a depression in the posteroinferior quadrant of the head of the femur, provides attachment to the ligament of the head of the femur, transmitting vessels to the head of the femur. The ligament is often disrupted, leading to avascular necrosis of the head of the femur. The morphometry and morphology of the head of the femur and fovea capitis are useful in various clinical conditions involving the hip joint. The study aims to assess the morphology and morphometry of the head of the femur and fovea capitis and to correlate these with clinical implications.

METHODS

 The study was conducted in the Department of Anatomy, Uttar Pradesh University of Medical Sciences (UPUMS), Saifai, India, using 40 femora of unknown age and sex. The morphometry was done using a digital vernier caliper, and morphological forms were observed.

RESULTS

 The mean perimeter of the femoral head was 12.3 ± 1.09 cm, and that of the fovea capitis was 4.2 ± 0.9 cm. The area of the femoral head was 48.27 ± 1.02 cm², and that of the fovea capitis was 4.84 ± 0.1 cm². The most common morphological form was oval-shaped, constituting 50%, followed by circular and triangular shapes. The least common morphological form observed was irregular-shaped.

CONCLUSION

 The information provided in this study will be of utmost use in dealing with hip joint pathologies like dysplasia and osteoarthritis, reconstructing injured ligaments of the head of the femur, proximal femur measurements, radiological interpretation, arthroscopic procedures, and other surgical interventions involving the hip joint.

N, T. S, Ramachandran K. An anatomico-morphometric analysis of proximal femur

The proximal femur is an important area of interest as it is involved in the articulation of the hip joint and it contributes to the mechanics of locomotion and the weight bearing capacity of the femur. Pathologies like osteoporosis and fractures are common in this site, and surgical interventions like hip arthroplasty and internal fixtures with implants rely on knowledge about the anatomy of the proximal femur to ensure effective treatment. Hence, a greater understanding of these variations will be helpful in constructing better fitted prosthesis. In this study, six morphometric parameters of the proximal femur were studied and measured in 100 dry adult femur bones - head diameter, transverse diameter of fovea, longitudinal diameter of fovea, diameter of neck, intertrochanteric line length, neck shaft angle and correlations were noted. The data obtained is specific for the southern Indian population and hopes to aid in production of better fitted hip prostheses for patients.

The morphometry, localization, and shape types of the fovea capitis femoris, and their relationship with the femoral head parameters

PURPOSE

The aim of this study was to investigate the morphometric properties of the fovea capitis femoris (FCF) and its localization on the femoral head, the shape types, and the relationship with the femoral head parameters.

METHODS

This study was performed on 146 dry femora. The morphological and morphometric properties were evaluated on dry bones and digital images of these bones. Some of the FCF and femoral head parameters were measured with a caliper on dry bones while others were measured using ImageJ software on digital images.

RESULTS

The most common localization type was the Type 2 localization and the shape type was the oval type. The FCF sizes [except depth of the FCF (D_FCF)] were found to be smaller in the Type 1 localization. The femoral neck shaft angle (NSA) was found to be greater in the triangular type than the round (or circular) type on the left side and in all cases. The vertical diameter of the femoral head (FHD-V), the anteroposterior diameter of the femoral head (FHD-AP), and the area of the femoral head (AREA_HOF) values were greater in the triangular types than in the oval types in all cases. There was no relationship between the localization types and the shape types of the FCF.

CONCLUSION

Results showed that the morphometric properties, localization, and shape types of the FCF were related to some femoral head parameters. It is thought that our findings contributed to orthopedic and radiological applications and anthropological sciences.

The early failure of the gamma nail and the dynamic hip screw in femurs with a wide medullary canal. A biomechanical study of intertrochanteric fractures

BACKGROUND

Intertrochanteric fractures may occur in a bone with a wide medullary canal that may lead to significant mobility of a intramedullary nail, contrary to an extramedullary device. This study evaluates the Dynamic Hip Screw and the gamma nail in AO 31.A2.1 fractures in these circumstances.

METHODS

Synthetic femora with canals drilled to 18 mm were used. Five fixation types were examined: a 2 - hole and a 4 - hole Dynamic Hip Screw with a 2 - hole plate, a standard gamma nail with dynamic and static distal locking and a long gamma nail. The specimens were tested with cyclic axial loading, from 500 N increasing of 50 N increments in each cycle. Force at failure, overall stiffness, stiffness at the fracture site, location and mode of failure were recorded.

FINDINGS

The short gamma nails dislocated into varus under preload because the nail migrated laterally. The Dynamic Hip Screw was initially stable, but some specimens rotated around the lag screw. The gamma nail was rotationally stable. Both implants failed through femur fracture. The long gamma nailed failed by screw cut - out at forces lower than the ultimate force of the short gamma nail.

INTERPRETATION

This study shows that the gamma nail is unstable in a large medullary canal but offers better rotational stability of the proximal fragment. A modification of the nail design or the operative technique may be considered.