The causes of hip and pelvic pain are numerous, sometimes making the diagnosis difficult.
Detailing these features may help to establish the diagnosis.
Age Consider the age of the child with hip pain. For example, LCP disease is most common in boys in middle childhood. SCFE must be considered in the older child or adolescent. Overuse syndromes are most common in the adolescent.
Onset Acute onset is suggestive of injury or a rapid onset of infection. SCFE may be chronic or sudden. Acute slips are characterized by a mild injury and inability to walk. LCP disease onset is usually insidious. Overuse syndromes are most painful when active.
Spontaneous movement The most consistent physical finding for septic arthritis of the hip is a loss of spontaneous movement of the affected limb.
Systemic illness The child is ill with septic arthritis, and less sick with toxic synovitis, rheumatoid spondylitis, and tumors.
Resting position of the limb Intraarticular hip disorders usually result in the spontaneous positioning in slight flexion and lateral rotation. This position reduces the intraarticular pressure.
Tenderness Palpate to determine the site of tenderness.
Hip rotation test Guarding and a loss of medial rotation suggest the problem is within the joint.
Night pain Nocturnal pain suggests the possibility of a malignant tumor.
Back stiffness Limitation of forward bending suggests that the disorder may be referred from the spine.
Establish the diagnosis by considering the features and the common causes of hip pain.
Infection is a common cause of pelvic pain. The early diagnosis of septic arthritis is critical because it may severely damage or destroy the hip joint. Because of the tenuous vascularity of the hip, joint infections must be diagnosed and drained promptly. Soft tissue abscess, such as the psoas abscess, may be suspected by the finding of tenderness on rectal examination and soft tissue swelling on the AP radiograph of the pelvis. Confirm the diagnosis by CT or MRI studies. Sacroiliac infections are identified by bone scans.
Stress injuries or repetitive microtraumas may cause hip pain. Such pain is most common during the second decade and often follows vigorous activity. It may involve the upper femur, but more commonly it involves the origin of muscles such as the greater trochanter and iliac spines. The diagnosis is usually suggested by the history, physical findings of localized tenderness, and negative radiographs but a positive bone scan.
Tumors A variety of tumors occur about the hip and pelvis. Osteoid osteoma is common in the proximal femur and produces pain in a pattern that is nearly diagnostic. The pain is nocturnal and relieved by aspirin. The tumor produces reactive bone with a radiolucent nidus on conventional radiographs.
Toxic synovitis is a idiopathic benign inflammation of the hip joint that occurs in children. This condition is important, as it may be confused with septic arthritis and less commonly with LCP disease. The condition causes pain and irritability of the hip. It subsides spontaneously over several days.
Idiopathic chrondolysis This uncommon condition is seen in late childhood or adolescence. The hip becomes painful and stiff, and joint space narrowing is present.
Rheumatoid spondylitis Unlike juvenile rheumatoid arthritis, hip involvement may be the first sign of rheumatoid spondylitis. Establish the diagnosis with serologic tests.