Imaging Findings

Based on the provided X-ray plain films, bone scan, and MRI images, the following observations can be made:

• In the sacral region, there is extensive cortical thinning and changes in the bone. The vertically oriented or lattice-like thickening of the trabeculae presents a “corduroy-like” appearance.
• The bone scan shows increased radiotracer uptake in the sacrum, suggesting metabolic or blood supply abnormalities in this area.
• MRI demonstrates a large lesion centrally and partially laterally within the sacrum. On T1-weighted images, the lesion appears slightly low or isointense, while on T2-weighted images, it shows a high signal with relatively well-defined margins. A certain degree of soft tissue component can be seen protruding from the lesion, potentially compressing adjacent neural structures.
• The lesion is relatively well-demarcated from surrounding normal bone. No obvious fracture line is visible, yet the patient reports significant lower back and left lower extremity pain, suggesting possible nerve compression or invasion.

Potential Diagnoses

Taking into account the patient’s age (47-year-old female), primary complaint (“severe back pain and left lower extremity pain”), and imaging characteristics, the following differential diagnoses are considered:

1. Osseous Hemangioma (Vertebral Hemangioma or Sacral Hemangioma)
   This is the most common benign vascular tumor of bone. On imaging, it often shows “vertical striation” or “lattice-like” bone changes. On MRI, it usually presents as high or intermediate signal on T1 and high signal on T2. Large lesions may include a soft tissue component and exhibit neural compression symptoms.
2. Metastatic Bone Tumor
   Although metastatic lesions are common in middle-aged and older adults, they typically present with lytic or mixed destructive changes and may include a history of primary cancer or multiple bone lesions. Further differentiation is needed.
3. Chordoma
   Chordomas commonly occur in the midline of the sacrum and often show lytic bone destruction on imaging. MRI signal characteristics are typically associated with its myxoid stroma, which can differ from hemangioma.
4. Other Primary Bone Tumors or Giant Cell Tumor of Bone
   Giant cell tumors frequently arise at the epiphysis and extend to the metaphysis. On MRI, they do not typically show such high signal intensity as hemangiomas and often have a tendency to invasively breach the cortical bone.

Final Diagnosis

In summary, considering the patient’s age, clinical symptoms, and the imaging characteristics (including the “striped” bone changes, extensive T2 hyperintensity, and the typical features of a vascular lesion), the most likely diagnosis is:

• Sacral Hemangioma (Intraosseous Hemangioma of the Sacrum)

If there remain uncertainties regarding the differential diagnosis, further CT-guided biopsy or detailed MR sequences can help exclude malignancies.

Treatment Plan and Rehabilitation

For sacral hemangioma, treatment options depend on lesion size, severity of symptoms, and neurological involvement:

1. Conservative Treatment
   Suitable for patients with mild symptoms or without significant nerve compression. Pain relief can be facilitated using physical therapy, analgesics (e.g., NSAIDs), or nerve root blocks.
2. Interventional or Surgical Treatment
   • Embolization: In vascular hemangiomas with rich blood supply, preoperative arterial embolization can reduce intraoperative bleeding.
   • Percutaneous Vertebroplasty (Cement Injection): Helps stabilize the lesion and relieve pain.
   • Surgical Resection or Decompression: For large lesions with severe neurological compression or high fracture risk, surgical removal and nerve decompression may be considered.

Rehabilitation and Exercise Prescription Recommendations:

• Acute Phase: Focus on pain relief and avoiding excessive loading. Short-term bed rest, gentle lumbar stretching, and muscle relaxation exercises for the back are recommended.
• Remission Phase: Once pain is manageable, gradually introduce core muscle strengthening exercises such as planks or supine pelvic lifts for 10–20 seconds at a time, resting 30 seconds between sets, 2–3 sets per day. Maintain controlled, steady movements to prevent aggravation of pain.
• Stable Phase: Moderate aerobic exercises like swimming or using an elliptical trainer can be performed 3–5 times a week for 20–30 minutes each session at a moderate intensity (“moderately demanding” by self-assessment).
• Advanced Strengthening: If recovery is favorable following surgery or interventional treatment, introduce low-impact weight-bearing exercises such as slow walking or low-intensity squats (like wall sits) to strengthen the lower limbs and back. Ensure proper protection and progress gradually.
• FITT-VP Principle:
  Frequency, Intensity, Time, Type, Volume, and Progression should be customized based on the patient’s pain and functional recovery, adjusting the exercise plan accordingly.

Safety Note: If pain, numbness, or other neurological symptoms worsen, seek timely medical review to reassess and determine whether to modify the treatment strategy or pause certain exercises.

Disclaimer

This report is based on the available imaging and clinical information for preliminary analysis and is provided for reference only. A definitive diagnosis and treatment plan require a comprehensive patient history, physical examination, and further diagnostic tests. Please consult a qualified physician or specialized medical institution for personalized medical advice.