What should you know about bilateral Perthes disease?

The affected bone weakens and later rebuilds as the child grows. Each hip may be at a different stage and may not be affected equally. Care aims to preserve comfortable movement and keep the femoral head well positioned in the socket while healing and reshaping occur.

Perthes disease can present with limping, reduced hip movement, and pain felt in the hip, groin, thigh, or knee. When both sides are involved, a limp may be less obviously one-sided, so changes in stride, stiffness, or avoidance of active play can be useful clues.

Clinicians compare hip movement and follow the shape and coverage of each femoral head on imaging. The child's stage of growth, the extent of bone involvement, motion, pain, and changes over time all influence the care plan. Bilateral disease may also prompt the specialist to consider whether another skeletal or medical condition could resemble Perthes disease.

Keep scheduled paediatric orthopaedic reviews even when pain settles, because hip shape can change during healing. Follow the team's advice about running, jumping, contact activities, and weight-bearing. Lower-impact movement may be chosen to maintain mobility without repeatedly loading an irritable hip.

Paediatric physiotherapy can provide range-of-motion work, strength exercises, walking support, and practical adaptations for school and home. Some children are treated with observation and activity changes; others may need bracing, casting, or an operation such as osteotomy to improve containment. The approach is individual to each hip.

Contact the clinical team promptly for a clear increase in pain, a sudden refusal or inability to bear weight, noticeably reduced hip movement, or a worsening limp. Fever with a hot, very painful hip or a child who appears acutely unwell needs urgent medical assessment because infection and other urgent conditions must be excluded.

Ask what stage each hip is in, whether motion or femoral-head coverage has changed, which activities are currently suitable, and what physiotherapy should prioritise. Clarify the purpose of follow-up imaging and what findings might lead the team to discuss surgery.