Hip fractures Flashcards
risk factors for hip fractures
female
elder age
osteoperosis
how can hip fractures be categorized?
intra-capsular fractures
Extra-capsular fractures
basic anatomy of the femur
head, neck, greater trochanter (lateral), lesser trochanter (medial), intertrochanteric line, shaft (body)
the capsule of the hip joint
this is a strong, fibrous structure which attaches to the rim of the acetabulum on the pelvis and the intertrochanteric line of the femur. it surrounds the neck of the head of the femur,
vasculature of the hip
*retrograde blood supply (blood enters the distal portion of the blood without blood supply to the bottom)
medial circumflex femoral artery and lateral circumflex femoral artery join the femoral neck
branches of the atery run along the surface within the capsule towards the femoral head providing blood to the femorla head.
if there is a fracture of the intra capsular neck- this can damage the blood vessels - removes blood supply to the femoral head and leads to avascualr necrosis. intracpasular fractures therefore need to have the femoral head replaced with hemiarthroplasty / total hip replacements.
intra capsular fractures vs extracapsular fractures
INTERTROCHANTERIC LINE
Intra capsular: break in the femoral neck within the capsule of the hip joint which affects the area proximal to the intertrochanteric line. proximal to the point at which the joint capsule attaches to the femur
extra capsular: fracture occurs distal to the hip jiont cpasule.
Garden classification for intra-capsular neck of femur fractures
Grade I – incomplete fracture and non-displaced
Grade II – complete fracture and non-displaced
Grade III – partial displacement (trabeculae are at an angle)
Grade IV – full displacement (trabeculae are parallel)
non displaced fractures (intracapsular)
grade I an II
if the fracture has not displaced then this could mean that the femoral head may still hve intact blood supply. it may be possible therefore to preserve the femoal head without avasculr necrosis occuring.
tx: internal fixation (screws)
displaced fracture (intracapsular)
grade III and IV
the fracture has disrupted the blood flow to the head of the femur and therefore the femur needs REMOVING and REPLACING which can either be done with HEMIATHROPATY or. a TOTAL HIP REPLACEMENT
Hemiarthropathy for displaced, intracapsular hip fracture
involves replacing the head of the femur but leaving the acetabulum (socket) in place. Cement is used to hold the stem of the prosthesis in the shaft of the femur. This is generally offered to patients who have limited mobility or significant co-morbidities
Total hip replacement
Total hip replacement involves replacing both the head of the femur and the socket. This is generally offered to patients who can walk independently and are fit for surgery
extracapsular hip fracture
leave the blood supply to the head of the femur intact. Therefore, the head of the femur does not need to be replaced.
Intertrochanteric fractures (extra-Capsular Fractures)
between the greater and lesser trochanter.
management: dynamic hip screw (sliding hip srew)
A screw goes through the neck and into the head of the femur. A plate with a barrel that holds the screw is screwed to the outside of the femoral shaft. The screw that goes through the femur to the head allows some controlled compression at the fracture site, whilst still holding it in the correct alignment. Adding some controlled compression across the fracture improves healing.
Subtrochanteric fractures (extra-Capsular Fractures)
occurs distal to the lesser trochanter (but within 5cm of it)
The fracture occurs to the proximal shaft of the femur.
managemetn: intramedullary nail (a metal pole inserted through the greater trochanter into the central cavity of the shaft of the femur).
hip fractures summary:
- intracapsular
- non displaced: screw
- displaced: hemiathropathy / total hip replacement - extracapsular
- intertrochanteric: dynamic hip screw
- subtrochanteric: intramedullary nail
