Legg-Calvé-Perthes Disease (Perthes Disease)

Also known as: Perthes disease, Legg-Calve-Perthes disease, LCPD (Legg-Calve-Perthes disease), Calvé-Legg-Perthes disease, Childhood femoral head osteonecrosis, Pediatric hip osteonecrosis

Last updated: December 18, 2024

Legg-Calvé-Perthes disease (Perthes disease) is a childhood hip disorder in which blood flow to the femoral head may be reduced, causing bone damage and weakening. The femoral head can lose its round shape and may flatten or fragment, later undergoing revascularization and remodeling, sometimes with lasting deformity. It often causes hip or groin pain and may refer pain to the thigh or knee; outcomes relate to age at onset.

Key Facts

•Legg-Calvé-Perthes disease represent a childhood hip disorder in which blood flow to the femoral head become reduced or disrupted, leading to osteonecrosis of the capital femoral epiphysis
•Hip or groin pain that worsens with activity and occurs at rest during symptomatic periods
•Diagnosed through history, physical exam, and imaging
•First-line treatment includes exercise, weight management, and activity modification

What It Is

Legg-Calvé-Perthes disease may represent a childhood hip disorder in which blood flow to the femoral head can become reduced or disrupted, leading to osteonecrosis of the capital femoral epiphysis. The weakened femoral head can lose its spherical shape under typical loading, and the articular surface may become flattened or fragmented during the active phase. Over time, revascularization and bone remodeling can occur, although residual deformity may persist depending on the extent of collapse and the child’s age at onset. The condition often presents with hip-related pain and gait changes, and symptoms can be referred to the thigh or knee.

Affected Anatomy

This condition affects several structures in and around the joint:

•Femoral head (capital femoral epiphysis)
•Femoral head articular cartilage
•Femoral neck (proximal femur metaphysis/neck region)
•Acetabulum (hip socket) and acetabular labrum
•Hip joint capsule and synovium
•Medial and lateral circumflex femoral arterial branches supplying the femoral head
•Growth plate (proximal femoral physis)
•Hip abductor musculature (gluteus medius and minimus) influencing pelvic stability and gait

Common Symptoms

Symptoms can vary in intensity and may change over time. Common experiences include:

•Hip or groin pain that may worsen with activity and can occur at rest during symptomatic periods
•Referred pain to the anterior thigh or knee that may obscure the hip as the primary source
•Limping gait that can be intermittent early and may become more persistent with progression
•Reduced hip range of motion, often involving limited abduction and internal rotation
•Stiffness around the hip that may be more noticeable after periods of inactivity
•Muscle weakness or fatigue around the hip, with possible Trendelenburg-type gait features
•Leg length discrepancy that can develop due to femoral head/neck changes and altered growth
•Pain-related avoidance of weight-bearing activities that can reduce participation in sports or play

Causes and Risk Factors

Multiple factors can contribute to the development of this condition:

Causes

•Idiopathic reduction in blood supply to the femoral head that can lead to avascular necrosis and subsequent collapse during weight-bearing
•Vascular vulnerability of the developing femoral head in childhood, where transient compromise of epiphyseal perfusion may contribute to necrosis
•Possible coagulation or thrombophilia-related tendencies that can be associated with microvascular occlusion in some children
•Mechanical factors and repetitive loading that can contribute to deformation of a weakened femoral head during the fragmentation phase
•Inflammatory synovitis and increased intra-articular pressure that may further reduce femoral head perfusion in susceptible cases

Risk Factors

•Age in childhood, often between about 4 and 10 years, with risk patterns that can vary by population
•Male sex, with higher reported frequency compared with female sex in many cohorts
•Family history suggesting genetic susceptibility in some cases
•Low birth weight or growth-related factors that may be associated in epidemiologic studies
•Exposure to secondhand smoke or household smoking, which can be associated with increased risk in some studies
•Socioeconomic factors that may correlate with risk in population studies, potentially reflecting multifactorial influences
•Hyperactivity or high activity levels that can increase mechanical loading during vulnerable phases
•Potential underlying clotting tendency (thrombophilia) that can be associated in a subset of affected children

How It's Diagnosed

Diagnosis typically involves a combination of clinical assessment and imaging studies:

•Clinical history and symptom characterization, including onset of limp, activity-related pain patterns, and possible referred knee pain
•Physical examination assessing hip range of motion (often abduction and internal rotation), gait evaluation, and functional testing for abductor weakness
•Plain radiographs of the pelvis/hips (anteroposterior and frog-leg lateral views) that can show sclerosis, fragmentation, flattening, and containment status depending on stage
•Magnetic resonance imaging (MRI) that can detect early ischemic changes and marrow abnormalities before radiographic changes become prominent
•Follow-up imaging over time to stage disease evolution (necrosis, fragmentation, reossification, remodeling) and to monitor femoral head shape and containment
•Differential diagnosis evaluation to distinguish from transient synovitis, slipped capital femoral epiphysis, septic arthritis, juvenile idiopathic arthritis, and fracture, often using clinical and imaging features
•Occasional laboratory testing when infection or inflammatory arthritis is a concern, typically including inflammatory markers to support differential diagnosis rather than confirm Perthes disease

Treatment Options

Treatment approaches range from conservative measures to surgical interventions, often starting with the least invasive options:

Self-Care and Activity Modification

•Activity modification strategies that can reduce high-impact loading during symptomatic phases and may support comfort and function
•Assistive devices (such as crutches or a cane) that can reduce weight-bearing during painful periods and may help limit limp
•Casting or bracing approaches aimed at improving femoral head containment within the acetabulum in selected cases
•Observation with scheduled clinical and imaging follow-up in milder presentations, particularly in younger children with favorable prognostic features

Physical Therapy and Exercise

•Physical therapy focused on maintaining or improving hip range of motion (especially abduction) and strengthening hip stabilizers to support gait mechanics

Medications

•Nonoperative pain management approaches that can include anti-inflammatory medications as part of clinician-directed care plans

Surgery

•Surgical containment procedures such as femoral varus osteotomy that can improve femoral head coverage during remodeling in selected patients
•Pelvic osteotomy procedures (for example, innominate osteotomy) that can increase acetabular coverage and containment in appropriate cases
•Surgical management of residual deformity or impingement-related problems in later stages, which can include procedures addressing femoroacetabular impingement or hinge abduction patterns
•Management of long-term sequelae, where symptomatic degenerative changes in adulthood can be addressed with joint-preserving strategies or, in advanced cases, hip arthroplasty as part of specialist care

Prognosis and Recovery

The course of this condition varies between individuals:

•Outcome may depend on age at onset, with younger children generally having greater remodeling potential and more favorable femoral head sphericity after healing
•Extent of femoral head involvement and degree of collapse can influence the likelihood of residual deformity and later hip dysfunction
•Good containment of the femoral head within the acetabulum during active disease can be associated with improved femoral head shape during reossification and remodeling
•Some individuals may develop femoroacetabular impingement, limited range of motion, or early osteoarthritis in adolescence or adulthood, particularly when residual deformity persists
•Symptoms often evolve over months to years as the disease progresses through stages, and functional limitations can fluctuate with pain and stiffness

Hip Arthroscopy(Procedure)
Slipped Capital Femoral Epiphysis (SCFE)(Condition)
Hip Dysplasia (Developmental Dysplasia of the Hip)(Condition)

Frequently Asked Questions

Common symptoms include: Hip or groin pain that may worsen with activity and can occur at rest during symptomatic periods; Referred pain to the anterior thigh or knee that may obscure the hip as the primary source; Limping gait that can be intermittent early and may become more persistent with progression; Reduced hip range of motion, often involving limited abduction and internal rotation; Stiffness around the hip that may be more noticeable after periods of inactivity.

Diagnosis typically involves: Clinical history and symptom characterization, including onset of limp, activity-related pain patterns, and possible referred knee pain; Physical examination assessing hip range of motion (often abduction and internal rotation), gait evaluation, and functional testing for abductor weakness; Plain radiographs of the pelvis/hips (anteroposterior and frog-leg lateral views) that can show sclerosis, fragmentation, flattening, and containment status depending on stage; Magnetic resonance imaging (MRI) that can detect early ischemic changes and marrow abnormalities before radiographic changes become prominent.

Treatment options range from conservative measures to surgical interventions, including: Activity modification strategies that can reduce high-impact loading during symptomatic phases and may support comfort and function; Nonoperative pain management approaches that can include anti-inflammatory medications as part of clinician-directed care plans; Physical therapy focused on maintaining or improving hip range of motion (especially abduction) and strengthening hip stabilizers to support gait mechanics; Assistive devices (such as crutches or a cane) that can reduce weight-bearing during painful periods and may help limit limp; Casting or bracing approaches aimed at improving femoral head containment within the acetabulum in selected cases.