Trochanteric fractures of the thigh bone, or femur, are uncommon injuries. The trochanters can be fractured in isolation or as part of another type of hip fracture. Patients may develop hip or thigh pain with or without a known trauma causing the injury. Treatment depends on the cause and severity of the injury.
The greater and lesser trochanters are at the head of the femur near the hip joint. The greater trochanter is a large, bony prominence on the outside of the femur. It serves as a point of attachment for many muscles responsible for moving the leg at the hip joint. The lesser trochanter is a bony prominence on the inside portion of the femur. It is the site of attachment for the iliospoas muscle, which helps bend the hip joint. The intertrochanteric line is a rough ridge between the greater and lesser trochanters on the front of the femur.
Lesser Trochanter Fracture Causes
Lesser trochanter fractures can occur as isolated injuries or in combination with other fracture types. As isolated injuries, they're caused by forceful contraction of the iliopsoas muscle in adolescents or by benign or malignant bone tumors in older adults. Tumors can weaken the bone, leading to increased risk of fracture.
Lesser Trochanter Fracture Treatment
Isolated fractures of the lesser trochanter are rare and there is no consensus on how to best treat them. If the fracture is a simple avulsion fracture due to forceful contraction of the iliopsoas, surgery can help realign the bone fragments. An avulsion fracture describes a fracture that occurs when a piece of bone is detached due to the forces transferred through the tendon from a muscle contraction. With an avulsion fracture, the bone fragment still has the tendon piece attached to it.
If a tumor is present, the bone and tumor may need to be treated with a combination of surgery, chemotherapy and radiation. An orthopedic surgeon and cancer specialist work together to oversee treatment of a bone tumor.
Greater Trochanter Fractures Causes
A greater trochanter fracture most commonly occurs as part of an intertrochanteric fracture pattern. An intertrochanteric fracture is one in which the fracture line is through the intertrochanteric line of the femur. An intertrochanteric fracture can occur in conjunction with a greater trochanter fracture.
An isolated greater trochanter fracture is rare. It usually occurs in elderly patients due to direct trauma to the outside of the hip or indirectly due to powerful contraction of the gluteus medius and gluteus minimus muscles. The gluteus medius and minimus help move the hip by attaching to the greater trochanter.
Greater Trochanter Fracture Treatment
Greater trochanter fractures are usually treated without surgery. Nonoperative management consists of bed rest, initially. As symptoms subside, patients can begin to use crutches and perform stretches to help regain hip function. When the bone fragments are displaced more than 1 cm, surgery is usually performed to help realign the bone fragments and encourage healing. Surgeons often use wires under tension to help realign the bone fragments.
Prognosis for isolated trochanteric fractures depends on the level of displacement of the bone fragments and whether a tumor is present. Less displacement of bone fragments generally means a better outcome with conservative treatments, including the use of crutches and stretching exercises. With more displacement of the bone fragments, the outcomes are based on how well the surgery goes and what is done during the surgery to repair the fracture.
If a tumor was the cause of the fracture, the prognosis depends on the type of tumor, as the treatments range from fixing the fracture to having to remove large portions of bone in conjunction with radiation and chemotherapy.
- AAOS Comprehensive Orthopaedic Review; Jay Lieberman, M.D., editor; 2008
- Handbook of Fractures; Kenneth Koval, M.D. and Joseph Zuckerman, M.D., editors; 2006
- Wheeless' Textbook of Orthopaedics: Fractures of the Lesser and Greater Trochanter