Knee Joint Imaging Report and Analysis

I. Imaging Findings

According to the provided knee MRI sequences (coronal and sagittal views), abnormal bone signal is observed in the subchondral area of the femoral condyle, featuring the following characteristics:

• On T2-weighted images, a relatively high signal area can be seen in the lesion, differing from the surrounding normal bone marrow signal, suggesting abnormal bone or subchondral structure.
• Local signal changes beneath the cartilage surface may appear as a localized depression or irregular shape, indicating possible involvement of the subchondral bone plate.
• The integrity of the adjacent cartilage surface may vary; in some slices, the cartilage surface appears slightly rough or shows a suspicious crack.
• No obvious large loose bodies are detected in the joint cavity, but multi-sequence evaluation should be performed to assess any cartilage damage and the presence of small free fragments.
• No significant abnormal swelling or proliferative changes in the periarticular soft tissues; joint effusion is limited or moderate. Whether mild synovitis is present requires correlation with clinical findings.

II. Potential Diagnosis

Given the patient is a 12-year-old female primarily presenting with knee pain, and in view of the MRI findings showing subchondral bone lesions or focal bony changes, the possible diagnoses and differential diagnoses include:

1. Osteochondritis Dissecans (OCD)
   Features: Common among adolescents, especially those who are active in sports. Characterized by localized necrosis of the subchondral bone and potential loosening or detachment of the cartilage. MRI often shows subchondral signal abnormalities. If the lesion is relatively localized and the cartilage surface remains intact, it may suggest an early or relatively stable stage.
2. Osteochondroma or other benign bone tumors
   Features: Certain benign bone tumors can cause focal bony changes but usually exhibit characteristic tumor-like signals or calcification of the cartilage cap. They are less common in weight-bearing subchondral regions.
3. Traumatic bone contusion or subchondral fracture
   Features: If there is a clear history of trauma, bone contusions or incomplete fracture lines may be visible, often with bone marrow edema. Such findings typically correlate strongly with clinical trauma history.
4. Infectious or inflammatory changes
   Features: In the presence of infection or a significant inflammatory response, surrounding soft tissue swelling, bone marrow high signal, and more severe clinical symptoms (redness, swelling, heat, pain) may be noted. Laboratory indicators are often abnormal in such cases.

III. Final Diagnosis

Considering the patient’s age (12 years old, in a growth phase), clinical presentation (knee pain), and MRI findings (localized subchondral bony signal abnormality), the most likely diagnosis is Juvenile Osteochondritis Dissecans (JOCD).

Determination of lesion stability should be based on the integrity of the cartilage surface, MRI signal characteristics, and clinical follow-up. If the cartilage surface remains intact and a high T2 signal just indicates reparative granulation tissue, the lesion is more likely to be stable.

IV. Treatment Plan and Rehabilitation

1. Overview of Treatment Strategies

• Conservative Treatment: For stable lesions with an intact cartilage surface or only mild cartilage damage, reducing joint load or stopping high-impact activities can support self-healing. Knee braces or splints may be used if necessary. Regular imaging follow-up is recommended to monitor healing.
• Surgical Treatment: If clinical symptoms worsen, or MRI indicates cartilage rupture, loose body formation, or significantly unstable lesions, arthroscopic procedures (e.g., drilling decompression, fixation of loosened cartilage or fragments, or cartilage repair surgeries) may be considered.

2. Rehabilitation/Exercise Prescription Recommendations

Following the principle of gradual progression (FITT-VP), the following plan may be considered:

• Early Stage (Inflammatory/Acute Phase)
  During the acute phase or severe pain, focus on rest and reducing joint load. Mild muscle-strengthening exercises (e.g., isometric exercises for the quadriceps and hamstrings) can be performed 2-3 times per day, with duration adjusted based on individual tolerance. Avoid overexertion.
• Intermediate Stage (Recovery/Rehabilitation Phase)
  As pain subsides and the lesion stabilizes, gradually introduce low-impact exercises such as stationary biking or swimming 3-4 times per week, 20-30 minutes each session, at a moderate intensity (slight fatigue).
• Late Stage (Strengthening/Functional Recovery Phase)
  Progress to light weight-bearing activities and proprioception exercises, such as partial squats (avoid deep squats) and balance board training. Perform 3-5 times per week, gradually increasing intensity based on joint tolerance and imaging findings.
• Individualized Adjustments
  If the patient has fragile bones or open growth plates, proceed more cautiously with exercise. Monitor the joint’s response, and discontinue if any discomfort occurs.

Throughout the rehabilitation process, regular imaging follow-up and monitoring of pain and joint function is essential. If needed, rehabilitation exercises should be conducted under the guidance of a specialist or a physical therapist.

Disclaimer

This report is provided as a reference analysis based on current imaging and patient history and cannot replace a face-to-face clinical consultation or professional advice from a licensed physician. If you have any concerns or if symptoms worsen, please promptly seek examination and treatment at a qualified hospital.