The hip, buttock and thigh Flashcards
Describe the twisting of the lower limb during development
permanent pronation at the mid-thigh level makes the terminology in the lower limb confusing
Thing that were supposed to be posterior are now anterior
Why flexion of the knee is in posterior direction, whereas flexion of the elbow is anterior
What are the two major regions of the lower limb
The gluteal region (part of the trunk)
and
the “free lower limb” (thigh, leg and foot)
Summarise the bones of the region
The pelvis (the “hip bone”) Ischium Ilium pubis The femur
What is the difference between the thigh and leg
Thigh- hip and knee
Leg- knee and ankle
What type of bone is the patella
Sesamoid bone- does not form part of the knee joint
Formed within a tendon of a muscle
Patella is important as it helps maintain arrangement and minimise friction when a muscle is moving over the surface of a joint- to prevent damage to the muscle or the bone.
What 3 bones contribute to the hip joint
Each pelvic bone is formed by three bones (ilium, ischium, and pubis), which fuse during childhood. The ilium is superior and the pubis and ischium are anteroinferior and posteroinferior, respectively.
Describe how the pelvis is joined to the vertebral column
The ilium articulates with the sacrum. The pelvic bone is further anchored to the end of the vertebral column (sacrum and coccyx) by the sacrotuberous and sacrospinous ligaments, which attach to a tuberosity and spine on the ischium.
Summarise the relationship of the pelvis with the other parts of the body
The outer surface of the ilium, and the adjacent surfaces of the sacrum, coccyx, and sacrotuberous ligament, are associated with the gluteal region of the lower limb and provide extensive muscle attachment. The ischial tuberosity provides attachment for many of the muscles in the posterior compartment of the thigh, and the ischiopubic ramus and body of the pubis are associated mainly with muscles in the medial compartment of the thigh. The head of the femur articulates with the acetabulum on the lateral surface of the pelvic bone.
Describe the key features of the ilium
The upper fan-shaped part of the ilium is associated on its inner side with the abdomen and on its outer side with the lower limb. The top of this region is the iliac crest, which ends anteriorly as the anterior superior iliac spine and posteriorly as the posterior superior iliac spine. A prominent lateral expansion of the crest just posterior to the anterior superior iliac spine is the tuberculum of the iliac crest.
The anterior inferior iliac spine is on the anterior margin of the ilium, and below this, where the ilium fuses with the pubis, is a raised area of bone (the iliopubic eminence).
What is the name given to the surface of the hipbone that articulates with the sacrum
Auricular surface
Describe the gluteal surface of the ilium
The gluteal surface of the ilium faces posterolaterally and lies below the iliac crest. It is marked by three curved lines (inferior, anterior, and posterior gluteal lines), which divide the surface into four regions:
Describe the inferior gluteal line
The inferior gluteal line originates just superior to the anterior inferior iliac spine and curves inferiorly across the bone to end near the posterior margin of the acetabulum—the rectus femoris muscle attaches to the anterior inferior iliac spine and to a roughened patch of bone between the superior margin of the acetabulum and the inferior gluteal line.
Describe the anterior gluteal line
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The anterior gluteal line originates from the lateral margin of the iliac crest between the anterior superior iliac spine and the tuberculum of the iliac crest, and arches inferiorly across the ilium to disappear just superior to the upper margin of the greater sciatic foramen—the gluteus minimus muscle originates from between the inferior and anterior gluteal lines.
Describe the posterior gluteal line
The posterior gluteal line descends almost vertically from the iliac crest to a position near the posterior inferior iliac spine—the gluteus medius muscle attaches to bone between the anterior and posterior gluteal lines, and the gluteus maximus muscle attaches posterior to the posterior gluteal line.
Where is the ischial tuberosity located
The ischial tuberosity is posteroinferior to the acetabulum and is associated mainly with the hamstring muscles of the posterior thigh (Fig. 6.23). It is divided into upper and lower areas by a transverse line.
Describe the upper parts of the ischial tuberosity
The upper area of the ischial tuberosity is oriented vertically and is further subdivided into two parts by an oblique line, which descends, from medial to lateral, across the surface:
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The more medial part of the upper area is for the attachment of the combined origin of the semitendinosus muscle and the long head of the biceps femoris muscle.
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The lateral part is for the attachment of the semimembranosus muscle.
Describe the lower parts of the ischial tuberosity
The lower area of the ischial tuberosity is oriented horizontally and is divided into medial and lateral regions by a ridge of bone:
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The lateral region provides attachment for part of the adductor magnus muscle.
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The medial part faces inferiorly and is covered by connective tissue and by a bursa.
When sitting, this medial part supports the body weight.
The sacrotuberous ligament is attached to a sharp ridge on the medial margin of the ischial tuberosity.
Summarise the ischipubic ramus and pubic bone
The external surfaces of the ischiopubic ramus anterior to the ischial tuberosity and the body of the pubis provide attachment for muscles of the medial compartment of the thigh (Fig. 6.23). These muscles include the adductor longus, adductor brevis, adductor magnus, pectineus, and gracilis.
What are the two parts of the ischiopubic ramus
Inferior ramus of pubis
Ramus of ischium
What is the acetabulum
The large cup-shaped acetabulum for articulation with the head of the femur is on the lateral surface of the pelvic bone in the region where the ilium, pubis, and ischium fuse
Describe the margins and walls of the acetabulum
The margin of the acetabulum is marked inferiorly by a prominent notch (acetabular notch).
The wall of the acetabulum consists of nonarticular and articular parts:
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The nonarticular part is rough and forms a shallow circular depression (the acetabular fossa) in central and inferior parts of the acetabular floor—the acetabular notch is continuous with the acetabular fossa.
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The articular surface is broad and surrounds the anterior, superior, and posterior margins of the acetabular fossa.
Compare the lunate surface to the acetabular fossa
The smooth crescent-shaped articular surface (the lunate surface) is broadest superiorly where most of the body’s weight is transmitted through the pelvis to the femur. The lunate surface is deficient inferiorly at the acetabular notch.
The acetabular fossa provides attachment for the ligament of the head of the femur, whereas blood vessels and nerves pass through the acetabular notch.
Describe the consequences of a pelvic fracture
The pelvic bones, sacrum, and associated joints form a bony ring surrounding the pelvic cavity. Soft tissue and visceral organ damage must be suspected when the pelvis is fractured. Patients with multiple injuries and evidence of chest, abdominal, and lower limb trauma should also be investigated for pelvic trauma.
Pelvic fractures can be associated with appreciable blood loss (concealed exsanguination) and blood transfusion is often required. In addition, this bleeding tends to form a significant pelvic hematoma, which can compress nerves, press on organs, and inhibit pelvic visceral function
Describe some other types of pelvic fracture
Other types of pelvic ring injuries include fractures of the pubic rami and disruption of the sacro-iliac joint with or without dislocation. This may involve significant visceral pelvic trauma and hemorrhage.
Other general pelvic injuries include stress fractures and insufficiency fractures, as seen in athletes and elderly patients with osteoporosis, respectively.
When is synostosis of the hip bone complete and what is the acetabulum initially
Around 9 years
Acetabulum is a triradiate cartilage which closes when synostosis is complete
Summarise the femur
The femur is the bone of the thigh and the longest bone in the body. Its proximal end is characterized by a head and neck, and two large projections (the greater and lesser trochanters) on the upper part of the shaft
Describe the head of the femur
The head of the femur is spherical and articulates with the acetabulum of the pelvic bone. It is characterized by a nonarticular pit (fovea) on its medial surface for the attachment of the ligament of the head.
The head of the femur is covered in hyaline cartilage
Describe the neck of the femur
The neck of the femur is a cylindrical strut of bone that connects the head to the shaft of the femur. It projects superomedially from the shaft at an angle of approximately 125°, and projects slightly forward. The orientation of the neck relative to the shaft increases the range of movement of the hip joint.
The upper part of the shaft of the femur bears a greater and lesser trochanter, which are attachment sites for muscles that move the hip joint.
Describe the greater trochanter
The greater trochanter extends superiorly from the shaft of the femur just lateral to the region where the shaft joins the neck of the femur (Fig. 6.26). It continues posteriorly where its medial surface is deeply grooved to form the trochanteric fossa. The lateral wall of this fossa bears a distinct oval depression for attachment of the obturator externus muscle.
Describe the key features of the greater trochanter
The greater trochanter has an elongate ridge on its anterolateral surface for attachment of the gluteus minimus and a similar ridge more posteriorly on its lateral surface for attachment of the gluteus medius. Between these two points, the greater trochanter is palpable.
On the medial side of the superior aspect of the greater trochanter and just above the trochanteric fossa is a small impression for attachment of the obturator internus and its associated gemelli muscles, and immediately above and behind this feature is an impression on the margin of the trochanter for attachment of the piriformis muscle
Describe the lesser trochanter and its key features
The lesser trochanter is smaller than the greater trochanter and has a blunt conical shape. It projects posteromedially from the shaft of the femur just inferior to the junction with the neck (Fig. 6.26). It is the attachment site for the combined tendons of psoas major and iliacus muscles.
Extending between the two trochanters and separating the shaft from the neck of the femur are the intertrochanteric line and intertrochanteric crest.
Describe the intertrochanteric line
The intertrochanteric line is a ridge of bone on the anterior surface of the upper margin of the shaft that descends medially from a tubercle on the anterior surface of the base of the greater trochanter to a position just anterior to the base of the lesser trochanter (Fig. 6.26). It is continuous with the pectineal line (spiral line), which curves medially under the lesser trochanter and around the shaft of the femur to merge with the medial margin of the linea aspera on the posterior aspect of the femur.
Describe the intertrochanteric crest
The intertrochanteric crest is on the posterior surface of the femur and descends medially across the bone from the posterior margin of the greater trochanter to the base of the lesser trochanter (Fig. 6.26). It is a broad smooth ridge of bone with a prominent tubercle (the quadrate tubercle) on its upper half, which provides attachment for the quadratus femoris muscle.
Describe the angle of the shaft of the femur
The shaft of the femur descends from lateral to medial in the coronal plane at an angle of 7° from the vertical axis (Fig. 6.27). The distal end of the femur is therefore closer to the midline than the upper end of the shaft.
Describe the middle third of the shaft of the femur
The middle third of the shaft of the femur is triangular in shape with smooth lateral and medial margins between anterior, lateral (posterolateral), and medial (posteromedial) surfaces. The posterior margin is broad and forms a prominent raised crest (the linea aspera).
Describe the linea aspera
The linea aspera is a major site of muscle attachment in the thigh. In the proximal third of the femur, the medial and lateral margins of the linea aspera diverge and continue superiorly as the pectineal line and gluteal tuberosity, respectively (Fig. 6.27):
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The pectineal line curves anteriorly under the lesser trochanter and joins the intertrochanteric line.
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The gluteal tuberosity is a broad linear roughening that curves laterally to the base of the greater trochanter.
The gluteus maximus muscle is attached to the gluteal tuberosity.
The triangular area enclosed by the pectineal line, the gluteal tuberosity, and the intertrochanteric crest is the posterior surface of the proximal end of the femur.
What is the angle of inclination
The angle that the long axis of the shaft makes with the long axis of the head and neck
What determines the size of the angle between the long axis of the shaft and the vertical plane?
The width of the hips
What is the anterior protrusion between the ilium and the pubis called?
Ilipoubic eminence
Describe femoral neck fractures
Femoral neck fractures (Fig. 6.28) can interrupt the blood supply to the femoral head. The blood supply to the head and neck is primarily from an arterial ring formed around the base of the femoral neck. From here, vessels course along the neck, penetrate the capsule, and supply the femoral head. The blood supply to the femoral head and femoral neck is further enhanced by the artery of the ligamentum teres, which is generally small and variable. Femoral neck fractures may disrupt associated vessels and lead to necrosis of the femoral head.
Describe intertrochanteric fractures
In these fractures, the break usually runs from the greater trochanter through to the lesser trochanter and does not involve the femoral neck. Intertrochanteric fractures preserve the femoral neck blood supply and do not render the femoral head ischemic
Describe femoral shaft fractures
An appreciable amount of energy is needed to fracture the femoral shaft. This type of injury is therefore accompanied by damage to the surrounding soft tissues, which include the muscle compartments and the structures they contain.