Intertrochanteric hip fractures can be difficult to treat. With this type of hip fracture, there is a break or fracture line between two bony bumps on the femur (thigh bone). The larger bump on the upper outer part of the femur is the greater trochanter. The bump on the inside (medial) part of the femur is the lesser trochanter.
A line between these two bumps forms the intertrochanteric line. An intertrochanteric fracture between these two bumps usually requires surgical repair. If there are jagged pieces of bone on either side of the fracture, it’s called a comminutedfracture. This type of break is unstable.
In this article, Dr. S. Lichtblau of the Mt. Sinai School of Medicine in New York presents risk factors for an unstable intertrochanteric hip fracture. The orthopedic surgeon must watch out for these risk factors in older adults. Early identification can prevent a stable fracture from becoming an unstable one.
Identifying risk factors is important because it’s not always possible to know from the X-ray if there is a comminuted fracture. If it’s not repaired at the time of surgery, the whole hip can collapse at the fracture site during healing. The pin used to hold or fix the fracture can break or back out of place. The patient ends up with a shortened limb on that side. And the procedure is considered a failed surgery.
The examiner may be able to tell there is fracture displacement or separation of the fracture fragments by looking at the patient’s preferred hip and leg position. Patients with a shortened limb and hip internal rotation on that side need further evaluation.
X-rays are taken. The surgeon looks for some specific telltale signs of fracture instability at the fracture site. These include loss of contact between the two sides of the fracture line. There may be obvious displacement of the bone with gapping at the fracture site. Severe osteoporosis of the bone (loss of bone mass) requires further investigation. Sometimes more than one radiographic view is needed to see all aspects of the area.
Treatment is based on the location, type, and severity of fracture. If the corrected fracture becomes unstable, the surgeon has three choices. These are 1) revise or change the first procedure, 2) choose a different way to fix or hold the fractured bone while it heals, and 3) change how much weight the patient can put on that leg after surgery. The patient may have to be non-weight bearing on the operated leg for a period of time.
The author notes that although modifying the reduction is an option, it’s not a very good one. The best way to do this is uncertain and the results are variable. Angular (bending) forces through the femur to the hip called varus and valgus can produce increased hip instability.
It may be easier to change the method of fixation. In the first reduction surgery, the surgeon often uses a Dynamic Hip Screw. But in complex, fragmented fractures or stable fractures that have become unstable, a different kind of screw (lag screw) along with a circumferential (circular) wire may be needed.
A particularly challenging fracture is the reverse obliquity intertrochanteric fracture. This fracture line goes in the opposite diagonal direction as the typical intertrochanteric fracture.
Intramedullary nails can help stabilize this type of fracture. This type of fixation device was once used for typical intertrochanteric fractures. But there were too many complications and surgeons had to stop using them. They do seem to work well to stabilize reverse obliquity fractures.
An alternative method of fixation for reverse obliquity fractures is a metal plate attached with a screw. There are several types of plates to choose from. These include the Medoff Sliding plate, the Trochanteric plate, and the Percutaneous plate. The choice of plating depends on what type of compression and fixation is needed to stabilize the fracture.
Careful reduction and fixation of intertrochanteric fractures is needed to prevent displacement, nonunion, or malunion. The course of treatment selected may have to be changed if the fracture becomes unstable. Surgeons must evaluate each patient carefully for risk factors and monitor for any sudden changes. Early identification is the key to successfully treating a stable intertrochanteric fracture that has become unstable.