A patellar fracture is a break of the kneecap bone.
How do you fracture your patella?
Patella fractures are usually the result of a hard blow to the front of the knee - falling on the knee, dashboard impact etcetera.
A kneecap fracture can also occur without contact - during jumping or landing.
Types of patellar fracture
A simple fracture means that the injury does not break through the skin and a compound fracture means that it does. A comminuted fracture means that the bone has splintered in a number of directions, which makes management difficult and the outcome often poor.
Issues & controversies of patellar fractures
- The usual surgical treatment option is a wire, and it is generally right around the edges of the patella - a 'cerclage' wire
- The earlier the wire is put on and the edges of the fracture put together, the easier it is
- In any case it is difficult
- Even done early and under the image intensifier (a sort of dynamic X-ray machine) reduction may not be perfect (i.e. the edges may not come together properly)
- Poor reduction will almost certainly lead to patello-femoral arthritis (damage to the joint surfaces between the kneecap and the thighbone)
- Even a good reduction may progress to arthritis
- The most common alternative is removal of the patella (patellectomy) - itself problematic as full function seldom returns to the knee after patellectomy
- The newer technique of patellar resurfacing (putting a synthetic back to the kneecap) may be a viable alternative, but the jury is still out as to its current value