Abstract:
Studies on human proximal femur have been done in different areas of the globe. Variations
are found due to different levels of activity, race, genetics, clothing, lifestyle and
occupation. Accurate description of femoral morphometry is of great interest for
biomedical engineers and orthopedic surgeons, but data from different populations is
lacking. Such important data happens to be relevant for surgical issues such as for planning
surgery and intervention, correction of neck shaft angle, insertion of surgical screws after
a fracture and most importantly for prosthesis and implant design. Adequately shaped
implants are critical for fixation of femur after fracture or total hip arthroplasty to reduce
implant related complications such as change in leg length, dislocation from improper
positioning of implants, implant loosening and dislocation fractures. Significant
differences have been noted among African Americans, Caucasians, Chinese and other
Asian populations. Femoral head diameter (FHD), femoral neck diameter (FND), femoral
neck length (FNL), intertrochanteric length (IL), medial offset (MO), femoral vertical
offset (FVO), femoral axis length (FAL), hip axis length (HAL) and neck shaft angle
(NSA) are morphological parameters of human proximal femur, taken for diagnosis and
surgical intervention. Objective of this study were to compare the differences in proximal
femur geometry of right and left femur. To compare the differences in proximal femur
geometry among male and female. To compare differences among different ethnic groups
and to study associations of proximal femur geometry with BMI, lifestyle factors and
comorbidities. The study was conducted in PNS Shifa hospital Karachi from September
2020 to March 2021 after Ethical approval from Bahria University Medical and Dental
College. After an informed consent, anteroposterior radiographs of both hips of 75 adults
aged 20-70 years were included in the study. This study was designed to compare
differences of proximal femur parameters between male and female gender, right and left,
different age groups and most importantly between 5 ethnic groups of Pakistan and to note
any variations. Statistically significant results were observed between gender in all
parameters of proximal femur. The mean values of HD in males was 52.95±2.58mm and
females was 45.96±3.08mm. mean value for FND in male was 38.03±3.63mm and in
female was 31.99±2.65mm and this was statistically significant (p-value = 0.000). FNL in
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male was 53.10±7.96mm and in female was 45.82±6.41mm. The obtained mean value of
femoral intertrochanteric length in male was 68.93±5.29mm. The mean value in females
was 68.93±5.29mm. Mean of the values of femoral medial offset in males was
39.67±7.98mm. The mean value in females was 34.53±6.94mm. In males the mean femoral
vertical offset value was 61.82±8.39mm and in female the mean value was 49.02±8.18mm.
The following means were observed for male and female FNAL was 108.78±7.16mm for
male and 94.47±7.04mm for female. The mean hip axis length (HAL) in males was found
to be 126.46±8.19mm and in females it was observed to be 106.21±9.28mm. The mean
value of NSA of male was 132.23±5.544º and female was 132.085±6.597º. there was
insignificant decrease in NSA between male and female. Significant ethnic differences and
a decrease of NSA in age group is observed. It can be concluded that understanding and
knowledge of proximal femoral morphometry including variations and correlations among
them is vital for an orthopedic surgeon before undertaking any surgical procedure or
selection of a proper implant for the patient. Knowing morphological parameters of a
population is necessary for designing appropriate medical devices and prosthesis that fit
accurately to that population and minimize complications such as implant loosening and
implant related fractures