1. Imaging Findings

In the provided anteroposterior (AP) radiograph of the pelvis, the right hip joint space appears relatively narrowed compared to the left side, accompanied by slight morphological changes. There is no obvious sign of perilesional bony destruction. The soft tissue contours are generally intact, and no clear fracture lines are observed.

MRI images (including T1-weighted, T2-weighted, and STIR sequences) show a wedge-shaped bone marrow edema signal in the central area of the right femoral head: low signal on T1-weighted images and high signal on T2/STIR sequences. A small amount of joint effusion can be observed in the right hip joint cavity, with capsular thickening and mild synovial hypertrophy. No significant bony destruction or large necrotic area is evident, but there is a local thinning of the articular cartilage, suggesting possible cartilage pathology.

2. Potential Diagnoses

1. Idiopathic Chondrolysis of the Hip (ICH)
   Based on the patient’s age (11-year-old female), clinical presentation (unilateral hip pain and limping for one month), and the typical early imaging findings of a wedge-shaped bone marrow edema in the center of the femoral head, ICH is highly suspected. This condition is associated with progressive destruction of the articular cartilage and is commonly seen in children and adolescents.
2. Perthes Disease (Legg-Calvé-Perthes Disease)
   Common in children, also presenting with hip pain and limping. However, it often affects boys aged 4–10 years, and radiographic changes typically follow a characteristic process of femoral head collapse and subsequent repair. Currently, there is no obvious collapse or necrotic area in the femoral head on imaging, so this diagnosis is less likely.
3. Synovitis or Transient Synovitis of the Hip
   This can occur in children with hip pain and restricted movement, and MRI often shows significant synovial thickening and joint effusion, frequently accompanied by acute or infectious signs. Given the absence of fever or strong indicators of inflammation in the history, this is relatively less likely.
4. Slipped Capital Femoral Epiphysis (SCFE)
   More common in overweight adolescents, presenting with hip or knee pain. On X-ray, the femoral head typically appears displaced posteriorly and inferiorly. No clear sign of such displacement is observed here, making this diagnosis less likely.

3. Final Diagnosis

Considering the clinical symptoms (persistent hip pain, limping for one month, no obvious infection or fever) and the early MRI features (prominent wedge-shaped edema in the center of the femoral head, early thinning of the articular cartilage), the most likely diagnosis is Idiopathic Chondrolysis of the Hip (ICH).

4. Treatment Plan and Rehabilitation

Treatment Strategy:
1) Mainly conservative management: reduce weight-bearing, use assistive devices such as braces or crutches to relieve joint stress, and take oral or topical nonsteroidal anti-inflammatory drugs (NSAIDs) to alleviate pain and inflammation.
2) Regular imaging follow-up: assess the progression of the joint cartilage and bone structure. If further deterioration or lack of improvement occurs, surgical intervention (e.g., capsular release, arthrodesis, or arthroplasty) may be considered.
3) If any signs suggest infection or other complications, further blood tests and joint fluid analysis may be required to rule out infectious and other secondary causes.

Rehabilitation and Exercise Prescription (FITT-VP Principle):
1) Early Stage (Symptom Control Phase):

• Frequency: 3-4 times per week, primarily low-intensity rehabilitation exercises.
• Intensity: Focus on range-of-motion exercises and light muscle strengthening, avoiding weight-bearing or activities that cause marked pain.
• Time: 10-15 minutes per session, can be divided into segments and repeated multiple times a day.
• Type: Supine or seated passive or active range-of-motion exercises for the hip, such as small-range flexion, extension, abduction, and adduction, combined with isometric quadriceps exercises.
• Progression: Gradually increase the range of motion and repetitions based on pain tolerance and activity endurance.

2) Mid Stage (Functional Recovery Phase):

• As the pain subsides significantly, gradually introduce weight-bearing exercises. Elastic bands and other supports may be used for resistance training.
• Enhance core and lower limb muscle strength to ensure joint stability.
• 4-5 sessions per week, each lasting 20-30 minutes at moderate intensity. Avoid significant pain or excessive fatigue.

3) Late Stage (Advanced Rehabilitation and Return to Daily Activities):

• Gradually resume gait training and introduce low-impact aerobic exercises, such as swimming or cycling.
• Up to 5 sessions per week, each lasting 30 minutes or more, increasing intensity based on individual tolerance.
• Maintain joint flexibility and prevent disuse muscle atrophy.

Throughout the rehabilitation process, closely monitor pain, joint range of motion, and muscle strength. If any acute exacerbation or new symptoms arise, return for medical evaluation and adjust the rehabilitation plan accordingly.

Disclaimer: This report provides a reference analysis based on the available medical history and imaging findings and does not replace in-person consultation or professional medical advice. If you have any questions or if symptoms worsen, please seek medical attention promptly.