I. Radiological Findings

Based on the provided pelvis AP X-ray, the following observations can be made:

1. The right hip femoral head shows a noticeable morphological change. The femoral head appears slightly flattened, and the femoral neck demonstrates some degree of deformation, suggesting the presence of residual changes related to Legg–Calvé–Perthes disease (Perthes disease).
2. The left hip joint shows an imperfect alignment between the acetabulum and the femoral head. A screw in the proximal femur indicates surgical fixation, suggesting postoperative changes of slipped capital femoral epiphysis (SCFE).
3. Joint space: On the right hip joint, there is mild narrowing or unevenness of the joint space, which may indicate some degree of cartilage damage or reparative changes. The left hip joint’s congruence is generally acceptable, but due to the surgical fixation, postoperative healing and stability need to be assessed in combination with clinical observation.
4. No obvious soft tissue swelling is seen around the joints. Other pelvic structures appear essentially normal, with no apparent fracture lines or new bone abnormalities.

II. Potential Diagnoses

1. Legg–Calvé–Perthes disease (Perthes disease):
   • This disease is childhood ischemic necrosis of the femoral head, most common in children aged 4–8; it is more frequently seen in boys, although this case involves a female patient.
   • Radiographic findings typically include collapse, flattening, and changes in the density of the femoral head, followed by reparative and proliferative changes in later stages.
2. Slipped Capital Femoral Epiphysis (SCFE):
   • Commonly seen in adolescents, often associated with obesity and other risk factors; the typical presentation involves the femoral head epiphysis slipping posteriorly and inferiorly.
   • In this case, the presence of a fixation screw in the left proximal femur suggests surgical treatment for SCFE.
3. Other Considerations (such as post-traumatic secondary femoral head necrosis or osteochondral injury):
   • If there is a history of severe trauma or repetitive stress, post-traumatic osteonecrosis should be excluded. However, given the clinical history and imaging features in this case, the aforementioned two conditions are most likely to coexist.

III. Final Diagnosis

Taking into account the patient’s past medical history (right hip Perthes disease and left hip SCFE with internal fixation) and imaging findings, the most likely diagnoses are:

• Right Hip Joint: Late-stage changes post Legg–Calvé–Perthes disease
• Left Hip Joint: Postoperative changes following SCFE (internal fixation)

The current radiological findings are consistent with postoperative status and the long-term sequelae of Perthes disease. If further evaluation of joint cartilage, vascular supply, or physeal recovery is needed, MRI or additional imaging and clinical follow-up are recommended.

IV. Treatment Plan and Rehabilitation

1. Treatment Strategy Overview
   • Continued Follow-up Assessment: For Perthes disease at this stage, observe the remodeling of the hip joint and the range of motion. After SCFE surgery, monitor the stability of internal fixation and the reduction of the femoral head.
   • Corrective Surgery if Necessary: Should significant deformity or articular incongruence develop that affects patient function, consider secondary corrective surgeries or other interventions.
   • Medication and Supportive Therapy: Depending on pain level or joint inflammation, nonsteroidal anti-inflammatory drugs (NSAIDs) may be used as needed. Physical therapy, local heat application, or low-intensity ultrasound may be helpful to promote healing.
2. Rehabilitation / Exercise Prescription Suggestions
   • Early Phase (postoperative or active disease phase)
     • The main goal is to reduce stress on the joint while maintaining an appropriate range of motion, such as non-weight-bearing or partial weight-bearing with crutches.
     • Passive joint mobilization exercises can be performed to maintain joint flexibility and prevent hip contractures.
   • Intermediate Phase (recovery phase)
     • As tolerated, gradually increase weight-bearing activities, such as walking short distances with crutches or a walker.
     • Combine range-of-motion exercises with muscle-strengthening exercises, focusing on the muscles around the hip (iliopsoas, quadriceps, gluteus medius, etc.) through resistance band training, seated leg lifts, and similar activities.
   • Later Phase (consolidation phase)
     • Once the joint is stable and pain is manageable, low-impact exercises such as swimming or stationary cycling can be introduced to improve cardiovascular function and lower extremity muscle strength.
     • Gradually progress to regular walking or slow jogging, carefully monitoring any joint pain or changes in range of motion, and avoiding excessive loads.

   Adherence to the “FITT-VP” principle (Frequency, Intensity, Time, Type, Volume/Progression) is recommended. Begin with low intensity and short duration, gradually increasing both while closely monitoring joint function and pain.

   If there are concerns about bone fragility, overweight, or compromised cardiopulmonary function, exercise duration should be shortened, endurance training enhanced, and water-based or supportive activities used to reduce joint loading.

Disclaimer: This report is based solely on the provided images and text materials and is intended for reference only. It is not a substitute for an in-person consultation or professional medical advice. If you experience discomfort or any changes in your condition, please seek medical attention promptly.