INTRODUCTION :
The proximal end of the femur has been the object of much
attention. Knowledge of its anatomy is a prerequisite for a complete
understanding of the mechanics of the hip joint and serves as a basis for the
treatment of pathological conditions of the hip and femur. Extensive studies of
normal neck angles have been carried out. The values differ considerably in the
reports available. Differences in methods used, differing anatomical definitions
and variations between populations may account for this.
AIM : To evaluate the possible variation in the measurements of neck
shaft angle and ante version by Direct ,X-ray and CT –guided values in dry
femorae of adult Indian population. This correlation of measurements will help
us to identify a simple, reliable radiological method to evaluate the proximal
femoral angles and the data obtained in this study will help us to improve the
implant and prosthesis design for Indian population and enhance the functional
outcome of the patient.
Study type: analytical observational study – cross sectional type.
MATERIALS AND METHODS: 50 unpaired adult dry femorae of undetermined age and sex without gross pathology and abnormality from anatomy department, MMC will be used as the study material. Immature bones, bones with
abnormal pathology were excluded from the study.
ANTEVERSION:
Direct measurements by Kingsley Olmsted method
X-ray measurements were taken in dry femur by the method described by
KOSUKE OGATA et al- Biplanar radiography method-from AP view and
Lateral view of dry femur.
CT –measurements of anteversion were taken by measuring the angle between
neck horizontal axis and condylar horizontal axis in dry femur scannogram.
NECK –SHAFT ANGLE: The collo diaphyseal angle between the head neck
axis and the femoral shaft axis measured by direct, X-rays and CT methods.
RESULTS: The mean anteversion angle by Direct, X-ray and CT
measurements was found to be 10.3⁰, 10.4⁰, 9.9⁰ respectively. Among the three
methods the CT-guided method seems to be more accurate to measure the ante
version angle by Friedman test result. There was no significant difference in
which side (right/left) the sample bone belongs to. The mean neck shaft angle
by Direct, X-ray and CT measurements was found to be 131.9± 5.3, 130.3±4,
133.9±5 respectively. Among the three methods the X-ray method seems to be
more accurate to measure the neck shaft angle by Friedman test result. There
was no significant difference between right and left side bones.
CONCLUSION:
1. The simple biplanar radiography can be substituted as an alternative for CT
measurements to determine the NSA and AV preoperatively, though CT –
measurements give more accurate values.
2. The data obtained forms a strong base for future research in proximal femoral
angles in adult Indian population.
3. The proximal femur angles varies for each person even in Indian population
and the implants designed are mainly based on the data obtained from western
population. These radiological methods helps us to obtain pre operative proximal
femur angles to design specific implants to improve the efficiency of fracture
fixation and functional outcome
