Medical Analysis Report

1. Imaging Findings

According to the provided knee MRI images, there is a lobulated soft tissue lesion in the joint cavity, mainly located in the synovial area of the left knee. On T2-weighted images, it appears with high signal intensity, while on T1-weighted images, it may show an isointense or slightly low signal. The boundary of the lesion is relatively clear. This lesion is closely associated with the synovium of the left knee joint and may be accompanied by recurrent joint effusion or bleeding. During acute phases, mild edema can be seen in the surrounding soft tissues.

2. Potential Diagnoses

1. Synovial Hemangioma
   • Typically occurs in children or adolescents, often presenting as periodic or recurrent knee swelling and pain.
   • On MRI, shows high signal on T2, with vascular characteristics, and is prone to recurrent hemorrhage.
2. Pigmented Villonodular Synovitis (PVNS)
   • Often occurs in the knee joint, presenting with chronic swelling and arthritic symptoms.
   • Imaging often reveals synovial thickening and “villous” changes, with mixed signals on T2. Hemosiderin deposition may also be observed.
3. Synovial Chondromatosis
   • Characterized by multiple cartilaginous nodules within the joint synovium, forming cartilaginous bodies.
   • On T2-weighted images, these nodules appear as high-signal cartilage-like lesions, with common calcification or ossification visible on imaging.

In summary, based on the patient’s age, history of recurrent knee swelling and pain, and MRI showing vascular lesion characteristics, synovial hemangioma is highly suspected.

3. Final Diagnosis

Taking into account the clinical manifestations (periodic or recurrent knee swelling, pain, limited range of motion) and MRI findings (a lobulated soft tissue lesion with high signal on T2-weighted images), the most likely diagnosis is:

Synovial Hemangioma.

If further confirmation is needed, arthroscopic biopsy or intraoperative pathological examination can be done to precisely determine the nature of the lesion.

4. Treatment Plan and Rehabilitation

1. Treatment Strategies
   • Surgical Treatment: Primarily involves arthroscopic removal or open excision of the lesion along with partial or total synovectomy. In cases of extensive lesions or incomplete resection, additional therapies such as radiotherapy, cauterization, electrocoagulation, or sclerosing injections may be considered.
   • Conservative Treatment: If symptoms are mild or surgery is not tolerated, short-term use of analgesics and anti-inflammatory medications can temporarily relieve symptoms, but recurrences are common.
2. Rehabilitation and Exercise Prescription (FITT-VP Principle)
   • Early Rehabilitation:
     • Frequency: 3-4 times per week for rehabilitation exercises.
     • Intensity: Start at a low intensity, focusing on basic knee range-of-motion exercises and isometric muscle strengthening; avoid strenuous activity.
     • Time: 10-15 minutes per session, based on patient comfort.
     • Type: Primarily gentle knee flexion and extension exercises, as well as isometric quadriceps training to prevent muscle atrophy.
     • Progression: As symptoms improve, gradually increase the intensity and duration; for instance, expand range of motion to full flexion and extension, and add light weight-bearing exercises.
   • Intermediate and Late Rehabilitation:
     • Frequency: Increase to 4-5 times per week as tolerated.
     • Intensity: Once the lesion is confirmed stable, moderate-intensity functional training of the knee joint (e.g., seated or standing quadriceps strengthening) can be introduced.
     • Time: 20-30 minutes per session, adjusted according to tolerance.
     • Type: May include cycling, water walking, or swimming for low-impact aerobic exercise that promotes joint flexibility and muscle strength.
     • Progression: With improved joint stability, gradually increase the load and exercise duration while closely monitoring for any recurrence of swelling or pain.
   • Individual Precautions:
     • If recurrent swelling or pain occurs, promptly seek medical evaluation and suspend high-intensity activities.
     • For children whose bones are still developing, adjust exercise intensity based on bone age and fitness level to prevent secondary joint injury.

5. Disclaimer

This report is based on the provided information and should only be taken as a reference for medical analysis. It cannot replace an in-person consultation or professional medical advice. For specific diagnosis and treatment, please seek guidance from a specialist and consider a comprehensive evaluation of the patient’s condition.