Trochanteric fractures of the femur or thigh bone are not common 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.
Anatomy
The greater and lesser trochanters are on the thigh bone, or 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 rough ridge between the greater and lesser trochanters on the front of the femur.
Lesser Trochanter Fracture Causes
Lesser trochanter fractures can occur either as isolated injuries or in combination with other fracture types, according to Wheeless' Textbook of Orthopaedics. As isolated injuries, they're caused by forceful contraction of the iliopsoas muscle in adolescents or by benign or malignant bone tumors in the elderly. 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 is a facture that occurs when a piece of bone is detached due to the forces transferred through the tendon from a muscle contraction. In 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 orthopaedic surgeon and an oncologist together oversee treatment of a bone tumor.
Greater Trochanter Fractures Causes
A greater trochanter fracture most commonly occurs as part of an intertrochanteric fracture pattern, according to Wheeless' Textbook of Orthopaedics. An intertrochanteric fracture is a hip fracture in which the fracture line is through the intertrochanteric line of the femur. The 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 a direct trauma to the outside of the hip or indirectly due to 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 nonoperatively, according to the "AAOS Comprehensive Orthopaedic Review" edited by Dr. Jay Lieberman of the University of Connecticut. Nonoperative management consists of bedrest initially. As symptoms subside, patients can begin to use crutches and can perform stretches to help regain hip function. When the bone fragments are displaced more than 1 cm, surgery is usually performed to help realign bony fragments. Surgeons often use wires under tension to help anatomically realign the bone fragments.
Prognosis
Prognosis for isolated trochanteric fractures depends on the level of displacement of the bone fragments and whether or not 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 reason for 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.
References
- "AAOS Comprehensive Orthopaedic Review"; Dr. Jay Lieberman, editor; 2008
- "Handbook of Fractures"; Dr. Kenneth Koval, Dr. Joseph Zuckerman, editors; 2006
- Wheeless' Textbook of Orthopaedics: Fractures of the Lesser and Greater Trochanter
