Medical Imaging Analysis Report

I. Imaging Findings

• On the anteroposterior and lateral X-rays of the knee joint, an abnormal small bone fragment can be observed in the intercondylar eminence (tibial spine) region of the tibia, suggesting cortical discontinuity or the presence of fracture fragments in that area.
• MRI shows abnormal signal at the tibial attachment of the anterior cruciate ligament (ACL), with some ligament fibers connected to the fracture fragment; localized bone marrow edema is noted at the tibial spine.
• No significant extensive tearing is observed in the surrounding soft tissues. A small amount of effusion is present in the joint cavity, and the cartilage surface appears generally intact.
• No obvious signs of rupture or significant injury are noted in other ligaments (e.g., posterior cruciate ligament, medial or lateral collateral ligaments).

II. Potential Diagnoses

1. ACL Avulsion Fracture at the Tibial Attachment
   • The patient’s age and mechanism of injury (falling trauma to the knee) match the common population (8–13 years old) for this type of fracture.
   • X-ray shows a small bone fragment at the attachment site, and MRI further demonstrates the connection between the ligament and the bone fragment, along with bone marrow edema at the tibial spine.
2. Simple Tibial Spine Fracture
   • This is a selective fracture involving the tibial spine, which may not necessarily be associated with avulsion of the ACL. A careful assessment of ligament integrity is required; however, in this case, MRI evidence of ligament signal changes makes this less likely.
3. Partial ACL Strain or Tear
   • If it were purely a ligament injury, MRI would show partial interruption of ligament continuity or abnormal signal, but there would be no obvious bone fragment displacement.

III. Final Diagnosis

Based on the patient’s age of 12 years, history of trauma from a fall, and imaging findings, the most likely diagnosis is “ACL Avulsion Fracture at the Tibial Attachment.” This injury is relatively common in children and is associated with hyperflexion and internal rotation stress.

IV. Treatment Plan and Rehabilitation

According to the Meyers and McKeever classification, if the fracture fragment displacement is minor (Type I or II), conservative treatment may be considered; if the displacement is significant (Type III or IV), arthroscopic surgery or internal fixation is required to stabilize the fragment and protect ligament function.

• Conservative Treatment (for minimally displaced or stable fractures)
  • Use a cast or brace to keep the knee joint in an appropriate degree of flexion for several weeks, followed by a gradual increase in activity.
  • Avoid weight-bearing and excessive flexion-extension movements in the early stage to reduce the risk of secondary injury.
• Surgical Treatment (for significantly displaced or unstable fractures)
  • Arthroscopic reduction with internal fixation (e.g., screws or suture fixation) to ensure stable healing of the fracture fragment at the ligament attachment site.
  • Postoperatively, a brace is required, followed by a stepwise rehabilitation training program.

Rehabilitation/Exercise Prescription Suggestions (FITT-VP Principle)

The following rehabilitation training program should be carried out under the guidance of a specialist or physical therapist, and adjusted flexibly according to the patient’s individual recovery status:

1. Frequency: In the early stage, 1–2 sessions of light exercise per day, and as knee function improves, increase to 3–5 times per week.
2. Intensity: Begin with an intensity that does not cause significant pain or discomfort; as range of motion and muscle strength improve, progressively increase resistance training (e.g., choosing higher tension bands).
3. Time: Initially limit each session to 10–15 minutes, gradually extending to 30 minutes or more.
4. Type: Recommended phases include:
   • Early Stage: Quadriceps isometric contractions, straight leg raises, and non-weight-bearing range of motion exercises.
   • Intermediate Stage: Gradually introduce partial weight-bearing exercises (e.g., walking with crutches), balance training, and light strength exercises.
   • Late Stage: Jogging, shallow squats, lower extremity proprioception training, etc.
5. Progression: Based on pain, swelling, and joint stability; gradually increase the difficulty and load of the training.

If bone fragility or other medical conditions (e.g., poor cardiopulmonary function) are present, further reduction of training volume or shorter sessions may be needed, and close monitoring of the patient’s condition is necessary.

Disclaimer: This report is based on available imaging and medical history for reference purposes and does not replace face-to-face consultation or professional medical advice. If you have any questions or if symptoms worsen, please contact a specialist doctor or return to the hospital for follow-up treatment.