1. Radiological Findings

Based on the physical examination photos of the child’s hands and knees as well as related X-ray imaging data:

• Hand X-ray: There is a noticeable “cup-shaped” change in the distal metaphysis of the radius and ulna. The metaphyseal boundary appears rough and blurred, and the trabecular bone is sparse, indicating insufficient bone mineralization.
• Knee Joint X-ray: Similar expansion and poor calcification can be observed in the distal femur and proximal tibia metaphyses, with reduced bone density around the knee joint.
• Physical Presentation: Widening and swelling of the wrist and knee joints, along with mild genu varum or genu valgum (depending on the direction of the deformity), suggesting impaired endochondral ossification. In the anterior chest area, “rachitic rosary” or mild protrusion of the chest may be noted.

These changes indicate a bone mineralization disorder consistent with common radiological features of rickets (Vitamin D deficiency rickets).

2. Possible Diagnosis

Based on the child’s clinical presentation (growth retardation, pain and deformities of the wrist and knee joints, poor diet, lack of timely Vitamin D supplementation) and radiological findings, possible diagnoses include:

1. Nutritional Rickets (Vitamin D Deficiency Rickets)
   The most common clinical type, resulting from insufficient Vitamin D intake or inadequate exposure to sunlight, leading to bone mineralization impairment.
2. Hereditary Rickets (e.g., Vitamin D-resistant rickets)
   Relatively rare, caused by genetic defects leading to abnormalities in the Vitamin D metabolic pathway or renal phosphate reabsorption. There is often a family history or other specific manifestations.
3. Other Pathological Rickets
   Includes calcium-phosphorus metabolic disorders from severe liver, kidney, or intestinal diseases, which should be ruled out in clinical practice.

3. Final Diagnosis

Considering the child’s age, prolonged breastfeeding without adequate Vitamin D supplementation, picky eating habits, lack of sunlight exposure, and radiological changes, the most fitting diagnosis is: Nutritional Rickets (Vitamin D Deficiency Rickets).

If subsequent laboratory tests (such as blood calcium, phosphorus, alkaline phosphatase, and 25-hydroxyvitamin D levels) also match related characteristics, it can be further confirmed. In general, invasive tests (such as biopsy) are not necessary for this condition.

4. Treatment Plan and Rehabilitation

4.1 Treatment Strategy

• Vitamin D Supplementation: Oral cholecalciferol (Vitamin D₃) is preferred. The dosage should be calculated based on the degree of deficiency and the child’s weight. Generally, daily oral intake or higher-dose “stoss therapy” is followed by a maintenance dose under medical guidance.
• Calcium Supplementation: Encourage consumption of calcium-rich foods or use oral calcium supplements if necessary to meet normal skeletal development needs.
• Appropriate Sun Exposure: Engage in moderate outdoor activities (avoiding strong UV hours) to expose the skin to sunlight, promoting Vitamin D synthesis.
• Correct Poor Dietary Habits: Increase intake of foods rich in protein, various vitamins, and minerals. If needed, consult a nutritionist for a comprehensive nutrition assessment and guidance.
• Follow-up Monitoring: Attend regular follow-up visits to track blood calcium, phosphorus, alkaline phosphatase levels, and skeletal development. Adjust supplementation dosage based on laboratory findings.

4.2 Rehabilitation Exercises and Exercise Prescription

Once bone health gradually improves and symptoms subside, a progressive exercise program can help promote bone growth and strengthen muscles:

• Early Stage (when bone is still fragile and symptoms are more pronounced):
  • Choose safe and low-impact activities, such as gentle stretching, passive joint movements under adult supervision, or assisted standing exercises indoors.
  • Frequency: 1–2 times per day, each session about 10–15 minutes, with light intensity. Avoid excessive weight-bearing or high-intensity exercises.
• Intermediate Stage (when symptoms improve and bone mineralization gradually recovers):
  • Under the guidance of a physician or rehabilitation therapist, perform active joint movements, simple balance training, crawling, and light walking.
  • Frequency: 3–5 times per week, each session 15–20 minutes. Increase frequency and duration as tolerated.
• Later Stage (when bone condition has significantly improved):
  • Gradually introduce low-intensity running or ball games that are fun and engaging to strengthen lower limb muscles and improve coordination.
  • Frequency: About 5 times per week, each session 20–30 minutes. Intensity can range from light to moderate, with close monitoring of any deformity progression or discomfort.

Throughout rehabilitation, avoid high-impact or excessive load-bearing activities that could stress the bones. Ensure exercise safety and gradually increase load to match recovering bone quality.

Disclaimer: This report is for medical reference only and cannot replace an in-person consultation or professional medical advice. Specific treatment and rehabilitation plans should be formulated and adjusted by qualified healthcare professionals according to the patient’s actual condition.