Femur

Anatomy

The femur is the the longest Os of the lower extremity, largest (by its volume), and most solid (when one takes into account his strength to the mechanical constraints, Contraction of the muscles…) human body. The femur is composed of a body (the central part or Diaphyse) and of two ends or épiphyses. An extremely short collar links the end higher than the diaphyse. This upper part of the femur to the form of one 2/3 of sphere (a énarthrose) being encased in the Acetabulum of the Os coxal. In situation proximale, one finds two reliefs osseous, the Trochanter S (the small one and the large one), allowing the insertion of the certain muscles. These 2 projections or apophyses in fact are reserved for the insertion of muscles which are charged to make turn the bone on its axis. The épiphyses are provided with feeder holes for the passage of the blood-vessels. Low, the rough line also allows the insertion of other muscles, of which the Grand gluteus and the Biceps crural. Distalement, one finds two Condyle S (a médial and side) and a pit forming an articulation Trochléarthrose with the tibia and the Rotule.

In the position upright, it vertical, is not separated by a considerable interval, corresponding to the width of the basin, but tilted gradually in a lower position and médialement to approach the locus of the center of the body at its distal end, in order to make it possible the articulation of the knee to be nearest possible to the Ligne of gravity of the body. This angle of inclination varies from one person to another, and is larger at the Femme than at the Homme, due to the width of its basin. The femur, like all long Os, is divided into a body and two ends.

The cut of a femur shows a central or medullary cavity containing yellow marrow. This cavity is surrounded by the compact bone. This last is wrapped by a membrane, the périoste. Cut of the épiphyses watch of the spongy bone rich in cavities filled with red marrow. It is on this level that are born the blood cells. The articular zones of the épiphyses are protected by cartilage artculaire.

Upper part

The higher end of the femur is organized in system of beams on the basis of three compact blades which are: the blade compacts intern or Arc of Adams, the external compact blade and the know-cervical compact blade. Blade compacts intern leaves the beam trochantérien towards the great trochanter. External compact blade, share the beam arciforme of Welshman towards the femoral head. Know-cervical blade, leave the osseous spans interns and external. This system of beams delimits a zone of weakness called triangle of Ward. The union of the beams arciforme and trochantérien gives a system called ogival system.

The head (caput femoris)

The head with the form of 2/3 of Sphere of approximately 24 mm of ray, and is directed to the top, towards the interior and a little forwards, the major part of its Convexité being above and ahead. Its surface is smooth, coated with Cartilage, except for depression ovoid, small cavity of head ( fovea capitis femoris , old small cavity of the round ligament), which is located a little under and behind the center of the head, and an attachment gives to the ligament of the femoral head ( ligamentum capitis femoris , old round ligament).

The collar (collum femoris)

The collar is a pyramidal flat bone, connecting the head with the body, and forming with this last a great angle (the angle cervico-diaphysaire). The angle is larger with the Enfance. Indeed, it is of 150° approximately at the newborn and decreases during the growth. At the Adult , the collar forms an angle of approximately 126° with the body, At the old man only 120°. In addition to projecting itself supérieurement and médialement body of the femur, the collar is projected also before (angle of antéversion), variablement at the individuals, going in general from 10° to 15°.

If the angle cervico-diaphysaire is higher than 130° one speaks about coxa valga , and if it is lower than 110° one speaks about coxa will vara . More the angle is small more there is a risk of fracture of the collar of the femur (frequency raised at the old man).

Trochanters

The trochanters are bump-spheres proéminantes which offer an arm of lever to the rotatory muscles of the thigh. Two trochanters are found: the large one and the small one.

Great trochanter

The great trochanter ( trochanter major ) is a quadrilateral eminence located at the junction of the collar with the upper part of the body. It is located slightly laterally and subsequently and, in the adult, is approximately 1 cm lower than the head. It has two surfaces and four edges. Side surface is used as insertion with the muscle Moyen glutéal ( gluteus middle finger , old muscle average gluteus). Surface médiale, smaller than side the, present one at its base a depression, the trochanteric pit ( fossa trochanterica , old digital small cavity), where the tendon of the external muscle Obturating ( obturator externus ). Above and ahead the place of the attachment of the internal Obturateur is and the muscles Jumeaux. The higher edge is the place of insertion of the muscle Piriforme. The lower edge gives rise to the upper part of the side Vaste ( vastus lateralis ). The former edge is prominent, the small muscle glutéal ( gluteus minimus , old musculus gluteus minimus) being attached to it.

Lesser trochanter

The lesser trochanter ( trochanter minor ) is a conical eminence which varies in size at various individuals. It projects inférieuropostérieure part of the base of the coll At his top sticks the Tendon muscle Ilio-psoas.

Tuber

A Prominence, the Tuber of the femur, is with the junction of the upper part of the collar and the great trochanter. It is the place of fastener of five Muscle S: Muscle musculus gluteus minimus laterally, the side Vast in lower part and the tendon of the internal Obturating and both Gemilli above.

Intertrochanteric line

Going down obliquely and médialement from the tuber, it offers a fastener to the ilio-femoral Ligament of the hip. Its lower part gives origin to the upper part of the vast médial (vastus medialis). The line quadrate (linea quadrata) is the place of origin of the femoral Quadriceps (quadratus femoris) and of some fibers of the Muscle large supply main.

Posterior part

The body

The body includes/understands three faces: former, posterior and postéro-intern.

The linea will aspera

The rough line or linea will aspera is an osseous peak vertically extending on the height from the femur, trifurcating in top and forking in bottom. It is between the faces posterior and postéro-external body of the femur. It is composed of two lips which widen in top and in bottom but meet on all the average part of the bone. One describes a median lip and side. On the median lip the median vast muscle of the quadriceps fits, whereas on the side lip fit the side vast muscle of the quadriceps, the Muscle large gluteus and the Muscle femoral biceps by its short belly. Between the two lips fit different the adductors from the thigh. To that is added the average branch, of trifurquation, on which the pectinate Muscle fits.

Distal part

The distal épiphyse of the femur supports: the surface patellar ( facies patellaris , old trochlée femoral), articular surface with the patella , and the condyles , two side eminences.

Patellar surface

It is located at the ventral part of the distal épiphyse femur, and has the shape of pulley, with 2 convex facets (from top to bottom and transversely): a side facet and a facet médiale, sizes unequal, continuing in bottom by the condyles and separated by a throat. The external cheek is however more convex, broader, higher and more projecting.

Condyles

The condyles are the articular surfaces located at the lower end of the femur. GG

The condyle médial

The condyle médial is located on the internal tuberosity of the femur.

The side condyle

The side condyle is located on the external tuberosity of the femur.

Ossification

to supplement

Fracture femur

The fracture of the femur is a frequent traumatism, particularly at the time of the accidents of the public highway. It can occur a serious complication and often mortal: the lubricating Embolism. This is why these fractures owe ostéosynthèsées beings quickly.

The pre-hospital assumption of responsibility is thus made normally by a ancillary medical medical team (Smur in France) or , which begins with sédater the victim and carries out the realignment of the member (reduction of the fracture). The immobilization of the fracture and the lower extremity is done typically with a Attelle of traction (standard splint of Donway), the immobilization of the hip is done in general with a Matelas immobilisator with depression.

The treatment more used currently is the Enclouage centromédulaire, which allows the resumption of immediate support and ata better rate of consolidation than the Ostéosynthèse by plate or the fixing use of external. It is necessary to count 3 months to obtain the consolidation.

The fracture of the collar of the femur is a traditional accident of the old Femme S , because of the Ostéoporose. Their death rate is very high (50% to 6 months) because of the Complications of décubitus and of the reduction in autonomy which they involve. The principal risk is the Nécrose femoral Tête. This is why in the event of important displacement or in Valgus (Stages 3 and 4 of Garden), it is necessary to pose a cephalic Prothèse. In the event of not moved fracture or of engraînée Fracture in Varus (Stage 1 and 2 of Garden) one can be satisfied with a Ostéosynthèse by nail-plate or dynamic Screw-plate.

Animals

the femur is also the bone of the thigh of the animals Tétrapode S.
it also acts of one of the long segments of the Patte of the arthropods

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