41-05: Musculoskeletal Injuries of the Hip

1. HIP FRACTURES

General Considerations

Approximately 4% of the 7.9 million fractures that occur each year in the United States are hip fractures. There is a high mortality rate among older adult patients following hip fracture, with death occurring in 8–9% within 30 days and in approximately 25–30% within 1 year. Osteoporosis, female sex, height greater than 5-feet 8-inches, and age over 50 years are risk factors for hip fracture. Hip fractures usually occur after a fall. High-velocity trauma is needed in younger patients. Stress fractures can occur in athletes or individuals with poor bone mineral density following repetitive loading activities.

Clinical Findings

A. Symptoms and Signs

Patients typically report pain in the groin, though pain radiating to the lateral hip, buttock, or knee can also commonly occur. If a displaced fracture is present, the patient will not be able to bear weight and the leg may be externally rotated. Gentle logrolling of the leg with the patient supine helps rule out a fracture. Examination of the hip demonstrates pain with deep palpation in the area of the femoral triangle (similar to palpating the femoral artery). Provided the patient can tolerate it, the clinician can, with the patient supine, flex the hip to 90 degrees with the knee flexed to 90 degrees. The leg can then be internally and externally rotated to assess the range of motion on both sides. Pain with internal rotation of the hip is the most sensitive test to identify intra-articular hip pathology. Hip flexion, extension, abduction, and adduction strength can be tested.

Patients with hip stress fractures have less pain on physical examination than described previously but typically have pain with weight bearing. The Trendelenburg test can be performed to examine for weakness or instability of the hip abductors, primarily the gluteus medius muscle; the patient balances first on one leg, raising the non-standing knee toward the chest. The clinician can stand behind the patient and observe for dropping of the pelvis and buttock on the non-stance side (eTable 41–3). Another functional test is asking the patient to hop or jump during the examination. If the patient has a compatible clinical history of pain and is unable or unwilling to hop, then a stress fracture should be ruled out. The back should be carefully examined in patients who report hip discomfort, including examining for signs of sciatica.