Perthes disease: Definition, Uses, and Clinical Overview

Posted on February 28, 2026 | by drhip

Perthes disease Introduction (What it is)

Perthes disease is a childhood hip condition where the ball of the hip joint temporarily loses part of its blood supply.
This can weaken the top of the thighbone (the femoral head) and change its shape over time.
It is most commonly discussed in pediatric orthopedics, sports medicine, radiology, and physical therapy.
People often encounter the term when a child develops a limp, hip or groin pain, or reduced hip motion.

Why Perthes disease used (Purpose / benefits)

Perthes disease is not a treatment or device; it is a diagnosis. The “use” of the term in clinical practice is to describe a specific pattern of hip joint injury and healing that affects growing children. Naming the condition helps clinicians and families communicate about what is happening inside the hip, what monitoring is needed, and which management options might be considered.

At a high level, recognizing Perthes disease helps with:

Explaining symptoms such as a persistent limp, activity-related hip or groin pain, thigh pain, or referred knee pain (pain felt in the knee even though the hip is involved).
Guiding evaluation and imaging (for example, deciding when plain X-rays are sufficient versus when MRI or other imaging may help).
Staging and prognosis discussions, because the condition evolves over time and the hip can remodel as a child grows.
Planning management, including activity modification strategies, physical therapy goals (such as maintaining hip range of motion), and when surgical containment procedures may be considered.
Reducing diagnostic delay, since early Perthes disease can look similar to other childhood hip problems.

Benefits, in this context, come from clearer diagnosis, appropriate follow-up scheduling, and coordinated care across pediatrics, orthopedics, physical therapy, and radiology. Outcomes and pathways vary by clinician and case.

Indications (When orthopedic clinicians use it)

Orthopedic clinicians consider Perthes disease in children who present with patterns that fit a pediatric hip disorder, such as:

A limp that persists or recurs without a clear acute injury
Hip, groin, upper thigh, or knee pain (especially when the hip exam is abnormal)
Reduced hip range of motion, commonly limited hip abduction (moving the leg out to the side) and internal rotation
Stiffness, fatigue, or pain that worsens with activity and improves with rest
Leg length difference noticed over time (can occur during the course of the condition)
Abnormal findings on hip imaging suggesting femoral head changes consistent with osteonecrosis (bone injury related to reduced blood supply)

Contraindications / when it’s NOT ideal

Because Perthes disease is a diagnosis, “contraindications” most often mean situations where another explanation is more likely or where a different diagnostic label better fits the findings. Clinicians may look beyond Perthes disease when:

Symptoms and exam findings point to infection or inflammation (for example, systemic illness, fever, severe pain, inability to bear weight), which can require urgent evaluation
The history and imaging suggest slipped capital femoral epiphysis (SCFE), another important pediatric hip condition with different typical age/body habitus patterns and management
There is concern for fracture, tumor, or other bone pathology, especially with night pain, progressive worsening, or atypical imaging
Hip pain follows a clear acute injury pattern more consistent with trauma-related conditions
The presentation fits transient synovitis (temporary hip inflammation) rather than the longer course expected with Perthes disease (final determination varies by clinician and case)
Imaging changes are better explained by other forms of osteonecrosis (for example, related to systemic disease, medications, or older age groups), since Perthes disease specifically refers to the pediatric idiopathic pattern

When considering management options (nonoperative vs operative), what is “not ideal” also depends on age, disease stage, hip shape, and functional limitation, and varies by clinician and case.

How it works (Mechanism / physiology)

Perthes disease involves a process of temporary disruption of blood flow to the femoral head (the “ball” of the hip joint). The femoral head is covered with cartilage and sits in the acetabulum (the “socket” of the pelvis). In growing children, bone is actively remodeling and the femoral head’s shape is influenced by both biology (healing) and mechanics (how forces pass through the joint).

High-level mechanism:

Reduced blood supply (ischemia) affects the bony part of the femoral head.
The weakened bone may undergo necrosis (cell death) and become structurally vulnerable.
Under everyday loading (standing, walking, running), the softened area can flatten or deform.
Over time, the body attempts revascularization and repair, replacing damaged bone with new bone.
As healing progresses, the femoral head can remodel, and its final shape depends on severity, stage, and how well the head remains centered in the socket during healing (often described as “containment”).

Key anatomy and tissues involved:

Femoral head and growth region (proximal femur): the primary site of bony injury and repair.
Articular cartilage: may remain relatively preserved compared with bone early on, but joint congruency (how well ball and socket match) can be affected if the bone shape changes.
Acetabulum (socket): may adapt to some degree as the child grows, but mismatch can contribute to stiffness and later joint wear.
Hip capsule and surrounding muscles: tightness and spasm can limit motion; muscle weakness may develop due to pain and reduced activity.

Onset, duration, and reversibility:

Perthes disease is generally not an instant event; it evolves over months.
The overall course can last months to years, as the femoral head goes through injury and healing phases.
It is often described as self-limited in the sense that revascularization and healing can occur, but shape changes may persist, and long-term hip mechanics depend on the final head-and-socket fit.
“Onset” and “duration” vary by clinician and case and by how early the condition is recognized.

Perthes disease Procedure overview (How it’s applied)

Perthes disease itself is not a single procedure. In practice, clinicians apply a structured evaluation and management pathway that may include observation, therapy, bracing, and/or surgery depending on the case.

A general workflow often looks like:

Evaluation / exam – Symptom history (limp, pain location, activity limits, duration) – Physical exam focused on gait, hip range of motion, and leg length – Screening for red flags that suggest urgent alternate diagnoses
Preparation (baseline planning) – Establishing a working diagnosis and differential diagnosis (other conditions that can mimic similar symptoms) – Discussing expected follow-up cadence and the role of imaging over time
Intervention / testing – Imaging typically starts with plain radiographs (X-rays) of the pelvis/hips – MRI may be used when early disease is suspected but X-rays are inconclusive, or when more detail about bone involvement is needed (use varies by clinician and case) – Classification and staging may be documented to help guide management discussions
Immediate checks – Review of pain, gait, hip motion, and imaging findings – Assessment for hip “containment” (how centered the femoral head sits in the socket) and whether motion limits are developing
Follow-up – Periodic reassessment of symptoms, function, range of motion, and imaging changes as the disease phase evolves – Adjustments to nonoperative measures (for example, therapy goals) or consideration of surgical options in selected cases

Specific treatment choices, timing, and monitoring intervals vary by clinician and case.

Types / variations

Perthes disease is often discussed in “types” or “variations” based on stage, severity, and patient factors rather than distinct sub-diseases.

Common ways clinicians categorize it include:

By disease phase (staging)
Many clinicians refer to stages that reflect progression from early changes to fragmentation and then healing/remodeling. The exact staging system used can vary.
By extent of femoral head involvement (severity classifications)
Systems such as Catterall grouping or the Herring (lateral pillar) classification are commonly referenced in orthopedic literature to describe how much of the femoral head is affected and to support prognosis discussions. Use and interpretation vary by clinician and case.
By age at presentation
Younger children may have more remaining growth and remodeling potential.
Older children may have less time for remodeling, which can influence management discussions.
By hip motion and containment status
Some cases maintain relatively good hip motion and containment.
Others develop stiffness, loss of containment, or progressive deformity that prompts closer monitoring.
By later outcomes
Some hips heal with a more spherical (“rounder”) femoral head.
Others heal with residual flattening or mismatch between the ball and socket, which can affect long-term joint mechanics.

Pros and cons

Pros:

Provides a specific diagnostic framework for a common pattern of childhood hip osteonecrosis and healing
Helps structure staged monitoring as the hip changes over time
Supports clear communication among orthopedics, radiology, physical therapy, and families
Encourages attention to hip range of motion and gait mechanics, not only pain
Allows clinicians to discuss risk and prognosis using established staging/severity descriptions (varies by clinician and case)
Can guide selection between nonoperative and operative pathways when appropriate

Cons:

Early symptoms can be non-specific, and the diagnosis can be missed or delayed
The disease course is long, often requiring repeated follow-ups and imaging
Outcomes can be variable, even with careful management (varies by clinician and case)
Some children develop persistent stiffness, deformity, or leg length difference
Imaging interpretations and classification systems can differ across clinicians
The term may be confusing to families because it names a process, not a single fix

Aftercare & longevity

“Aftercare” in Perthes disease usually refers to ongoing monitoring and rehabilitation needs throughout the disease phases and after healing. Since the condition unfolds over time, what matters most is how the hip’s shape, motion, and function evolve.

Factors that can influence longer-term outcomes include:

Severity and extent of femoral head involvement at presentation and as it evolves
Age and growth remaining, which affects remodeling potential
Hip range of motion over time, including whether stiffness develops
Containment and joint congruency, meaning how well the femoral head stays centered and how well the ball and socket match during healing
Activity level and loading patterns, which can affect symptoms and mechanics (specific restrictions vary by clinician and case)
Adherence to follow-up, since management often changes as imaging and function change
Physical therapy participation, when used, focusing on maintaining mobility and strength as directed by the care team
Comorbidities (other health conditions) that may affect bone health, healing capacity, or tolerance of interventions
If surgery is performed, recovery timelines, rehabilitation protocols, and durability depend on the procedure type and individual factors (varies by clinician and case)

Longevity is often discussed in terms of whether the hip heals with a shape that remains compatible with comfortable function into adulthood. Some individuals do well long term, while others may develop earlier hip osteoarthritis due to residual deformity; individual risk varies.

Alternatives / comparisons

Because Perthes disease is a diagnosis, “alternatives” usually mean other diagnoses that can resemble it, and “comparisons” often involve different evaluation tools or management pathways.

Diagnostic comparisons (what else it could be)

Transient synovitis: often shorter duration; symptoms may resolve more quickly, though clinicians sometimes monitor to ensure Perthes disease is not evolving.
SCFE: different underlying problem (growth plate slip) with distinct imaging features and typical age range; management is different and often more urgent.
Septic arthritis / osteomyelitis: infection-related conditions that may present with systemic symptoms and require urgent workup.
Inflammatory arthritis: may involve multiple joints or systemic features.
Stress injury or fracture: more tied to trauma or repetitive loading, depending on history.

Imaging comparisons

X-ray: widely available, often the first step; may be normal early in Perthes disease.
MRI: can detect earlier bone changes and show extent of involvement; availability and use vary.
Ultrasound: can show hip effusion (fluid) but does not characterize femoral head bone involvement as well as MRI.
CT: sometimes used for bony detail but involves radiation; use varies by clinician and case.

Management pathway comparisons

Observation/monitoring: used in selected cases, especially when symptoms are mild or imaging suggests limited involvement; requires follow-up.
Nonoperative management (therapy, activity modification, bracing in selected cases): often aims to maintain motion and support containment; intensity varies.
Surgery (selected cases): procedures may aim to improve containment or address deformity; risks and expected benefits depend on stage and individual anatomy.

No single pathway fits every patient; clinicians tailor decisions to age, stage, symptoms, hip shape, and family preferences.

Perthes disease Common questions (FAQ)

Q: Is Perthes disease the same as arthritis?
Perthes disease is not the same as arthritis. It is primarily a childhood condition involving temporary loss of blood supply to the femoral head and a healing/remodeling process. However, residual deformity from Perthes disease can affect joint mechanics and may contribute to earlier osteoarthritis later in life in some cases.

Q: Where is the pain felt with Perthes disease?
Pain is often felt in the groin or front of the hip, but it can also be felt in the thigh. Some children report knee pain because hip problems can refer pain to the knee. The exact pattern varies by individual.

Q: How is Perthes disease diagnosed?
Diagnosis typically combines symptoms, physical exam (especially hip range of motion), and imaging. X-rays are commonly used, and MRI may be added when early disease is suspected or to better define involvement. The choice of imaging and timing varies by clinician and case.

Q: How long does Perthes disease last?
The condition usually evolves over months to years as the femoral head goes through injury and healing phases. The timeline depends on disease stage at diagnosis and individual healing. Follow-up commonly continues until the hip has clearly entered a healing/remodeling phase.

Q: Does every child with Perthes disease need surgery?
No. Many children are managed without surgery, especially when hip motion is preserved and imaging suggests limited involvement. Surgery may be considered in selected cases based on age, severity, and containment; whether it is appropriate varies by clinician and case.

Q: Is Perthes disease “curable”?
Perthes disease often improves because the bone can revascularize and heal, but the final femoral head shape may not return completely to its original form. Some hips remodel well and function comfortably, while others heal with residual shape changes. Long-term impact varies by individual factors.

Q: What does “weight-bearing” mean in Perthes disease discussions?
Weight-bearing refers to how much body weight is put through the affected leg during standing and walking. Clinicians may discuss altering weight-bearing to manage symptoms or protect the hip during certain phases, but recommendations differ widely. Any specific restriction is individualized and varies by clinician and case.

Q: Can a child with Perthes disease still play sports?
Activity discussions usually focus on symptoms, hip motion, and disease stage. Some children remain active with modifications, while others are limited for periods of time to reduce pain and protect function. The appropriate level of sport participation varies by clinician and case.

Q: How much does evaluation and treatment typically cost?
Costs vary widely by region, insurance coverage, imaging needs (X-ray vs MRI), therapy visits, and whether surgery is involved. Hospital-based care and repeated follow-ups can also affect total cost. A clinic or insurer can provide the most accurate estimate for a specific situation.

Q: Can adults get Perthes disease?
Classic Perthes disease refers to the pediatric condition. Adults can develop osteonecrosis of the femoral head from other causes, but it is typically categorized differently. If an adult has hip symptoms and a history of childhood Perthes disease, current symptoms may relate to the healed hip shape and joint mechanics rather than active Perthes disease.