About fractured neck of femur. The decision to pin or not is not an arbitrary decision by the surgeon but based on clear parameters of what we know will work and what is unlikely to work. It's all based upon the type of fracture, the impact on the blood supply to the head and what stage the vascularity is at that time.
The circulation is complex
Here you can see the three lanes of blood supply, two of which, blue stars, are inevitably disrupted by the fracture. The third and central lane, green lines, is via the bone marrow itself and is also inevitably disrupted. If the third lane can be reconnected by a good and early fixation with pins, then the femoral head stands a good chance of surviving.
However, if the fracture is displaced and/or the time lapsed before surgery is done, the head is likely to have suffered early death - avascular necrosis - as a result. There is often no way for the surgeon to predict this with any certainty and it doesn't show up on xrays (no MRI at that time!) until one or even more days later.
Another aspect to know about is why they sometimes pin and other times do a hemi-arthroplasty (half a hip replacement). This is because of the nature of the fracture and the disruption of the blood supply.
Fractures are classified as
1. subcapital fracture
2. fractured neck of femur
3. intertrochnateric fracture
4. upper third fractured shaft
Here we shall only be discussion subcapital fractures.
Subcapital fractures are also categorised
So it can be seen that Types I, II and II can be fixed with pins or a sliding screw with a plate
These may or may not work depending upon
The circulation is complex
Here you can see the three lanes of blood supply, two of which, blue stars, are inevitably disrupted by the fracture. The third and central lane, green lines, is via the bone marrow itself and is also inevitably disrupted. If the third lane can be reconnected by a good and early fixation with pins, then the femoral head stands a good chance of surviving.
However, if the fracture is displaced and/or the time lapsed before surgery is done, the head is likely to have suffered early death - avascular necrosis - as a result. There is often no way for the surgeon to predict this with any certainty and it doesn't show up on xrays (no MRI at that time!) until one or even more days later.
Another aspect to know about is why they sometimes pin and other times do a hemi-arthroplasty (half a hip replacement). This is because of the nature of the fracture and the disruption of the blood supply.
Fractures are classified as
1. subcapital fracture
2. fractured neck of femur
3. intertrochnateric fracture
4. upper third fractured shaft
Here we shall only be discussion subcapital fractures.
Subcapital fractures are also categorised
So it can be seen that Types I, II and II can be fixed with pins or a sliding screw with a plate
These may or may not work depending upon
1. How accurate was the surgeon's perception of the category of the fracture - this can often
With Type IV, it clearly has to be replaced and this can be with one of the followingbe quite a difficult thing to do and it may not necessarily be the surgeon's fault if he makes a wrong call on it - he's only human, after all!
2. the quality of the bone in the head which is dependent upon the blood supplyif the blood supply has been severely compromised, the bone will very quickly display AVN, avascular necrosis or bone death, and show on an xray as a whiter bone than elsewhere.
The failure may present itself within days, weeks or even months after the initial fixation and subsequently require conversion to a hip replacement. But this should never be converted to a hemi-arthroplasty - see below
The failure may present itself within days, weeks or even months after the initial fixation and subsequently require conversion to a hip replacement. But this should never be converted to a hemi-arthroplasty - see below
1. hemi-arthroplasty
2. total hip replacement
2. total hip replacement