By Matthew Law

The femur is the uppermost bone of the leg, which is inside your thigh. It is very robust, and so it survives well archaeologically. The femur is the longest bone of the human skeleton (Brothwell 1981: 35)

Parts of it are very sexually diamorphic.

It is the best bone for estimating stature.

It has a well defined head, which forms a ball and socket joint with the pelvis. The head appears duirng the individual's first year of life as a separate bone, and fuses to the femur by the time the person is 15 - 20 years old.

The fovea is a hole on the head of the femur. It is where the ligamentum teres attaches. It is quite unusual for an articular joint to have an attachment, and so helps identify the head of the femur. The ligament stabilises the hip joint.

It has a very distinct neck, where the head connects to the shaft. This is frequently the site of fracture.

The angle between the neck and the shaft tends to be smaller in females (but there's a tremendous overlap).

At the top of the femur is the greater trochanter. This appears at 3 - 5 years and is fused with the femur by 15 -20 years. The lesser trochanter is behind, and appears at 9 - 12 years. This is also fused by 15 -20 years.

The femur swells out towards the distal end.

The knee joint is a common seat of pathology.

The joint surface on the condyles is very extensive.

The surface on the front is the surface on which the patella rests.

The ends of the femur are extremely vascular.

Trabeculae give strength to the neck of the femur - in osteoporosis these disappear. The entire human skeleton is replaced every seven years.

POSTERIOR

The lesser trochanter is on the posterior of the femur The psoas major muscle joins on here.

Cavalrymen often used to tear tendons here and bleed into the tendon, forming new bone. This is known as a Cavalryman's Spur. The process by which new bone is formed as a result of trauma is called Myositis Ossificans Traumatica.

The line down the back of the femur is called linea aspera.

The popliteal artery runs down the back of the knee - coachmen often used to get aneurysms here.

The gluteal muscles insert in a roughened area, which is sometimes very rough and known as the third trochanter.
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MEASUREMENTS__

If you stand the femur on end it isn't straight.

Measure maximum length (obtain by rotating until maximum is found), and oblique length (just a straight measurement).

Measure diameter of the head, and diameter at mid-shaft. The diameter of the head is sexually diamorphic. Greater than 45mm is typically male (like humerus).

The femoral index (FI) describes the degree of flattening at the upper end of the femur. It is calculated as (D1 / D2) x100, where:

D1 = antero-posterior diameter. Measure below lesser trochanter.
D2 = transverse diameter. Measured at the same place but on the other side of the bone. It is a larger measurement.

It is a convention to group results into two categories:

Platymeria = <85.0
Eurymeria = 85 - 99.9

Why do this? There is some suggestion that FI has increased over time.

You can also measure the distance across the end of the bone.

REFERENCES

Brothwell, D., 1981. Digging Up Bones, Third Edition. Ithaca: Cornell University Press