Legg-Perthes disease: long-term effects

After the active phase, the femoral head may heal with a shape that fits the socket well, or with less even contact. A changed shape can limit hip rotation, make the leg feel shorter, or cause a lasting limp. Some people have pain only with demanding activity; others develop persistent discomfort, stiffness, or hip osteoarthritis later in life. The presence of Perthes disease does not predict one fixed outcome for every person.

Symptoms can change after growth, so a new limp or loss of movement in an older child, teenager, or adult deserves assessment rather than being dismissed as an old diagnosis.

Regular movement that the hip tolerates can maintain strength and flexibility. Paediatric physiotherapy may help during growth, while an adult physiotherapist can adapt exercises later. Choose low-impact options during painful periods and build activity gradually. Weight management, supportive footwear when advised, and attention to muscle strength may reduce strain, but they cannot reshape a healed femoral head.

If symptoms interfere with sleep, work, walking, or exercise, an orthopaedic review can clarify whether imaging, targeted therapy, medication, or reconstructive surgery such as osteotomy is relevant.

Book a review for increasing groin or thigh pain, a new limp, reduced hip rotation, recurrent stiffness, or difficulty with stairs and daily activities. Seek urgent care for inability to bear weight, sudden severe pain after an injury, fever with a hot painful joint, or an acutely unwell feeling. These warning signs can have several causes and should be examined promptly.

Ask how the healed hip shape affects its socket, whether the other hip needs monitoring, which activities suit your current movement, and what symptoms suggest joint wear. If surgery is mentioned, ask what mechanical problem it would address and what rehabilitation would involve.