Imaging Findings

The patient is a 68-year-old male with a history of hypertension, dyslipidemia, atrial fibrillation, and peripheral vascular disease, presenting with left-sided sciatic pain. Imaging examinations (including X-ray, CT, and MRI) targeting the left hip and proximal femur reveal:

• A relatively well-demarcated bony lesion is seen in the proximal left femur (intertrochanteric region), appearing as a “geographic” lesion with a distinct sclerotic margin around it.
• Within the lesion, there are heterogeneous signals or density changes. Some components appear cystic/mixed in density, with additional imaging suggesting possible myxoid or fibrous tissue.
• CT demonstrates “dense–low density–sclerotic margin” coexisting within the lesion, with occasional irregular calcifications or lipomatous density structures. However, a clearly prominent fat component is absent.
• On MRI, the lesion shows mixed T1/T2 signals. Within the lesion, certain areas display low T1 signal and high T2 signal. After contrast enhancement, mild to moderate enhancement is observed in the myxoid matrix region, with a relatively well-defined boundary.
• There is no evident soft tissue invasion or marked cortical bone destruction, and the surrounding soft tissue structures show no significant edema or mass effect.

Potential Diagnosis

Based on the above imaging findings and the patient’s history, the possible diagnoses or differentials include:

1. Liposclerosing Myxofibrous Tumor (LSMFT): Typically occurs in the proximal femur. The lesion often shows a mixture of fibrous, myxoid, and minor fat components, along with a thick sclerotic rim and a geographic pattern of bone destruction.
2. Intraosseous Lipoma: Imaging usually shows a clear fat density, though it may have areas of necrosis, cystic change, and calcification. If the amount of fat is small or there is extensive degeneration, careful differentiation is required.
3. Fibrous Dysplasia (FD): Commonly presents with a “ground-glass” appearance. Compared to this case, FD often lacks a pronounced thick sclerotic margin and may show medial cortical expansion or endosteal scalloping.

Final Diagnosis

Considering the patient’s age, symptoms (relatively mild pain), and imaging features (a lesion in the proximal femur intertrochanteric zone with a thick sclerotic margin, mixed matrix, and no prominent fat signal), the most likely diagnosis is Liposclerosing Myxofibrous Tumor (LSMFT).

For further confirmation, imaging follow-up can be performed. If suspicious malignant features (such as rapid lesion enlargement, cortical bone destruction, or soft tissue mass) appear, a biopsy may be indicated to rule out malignancy.

Treatment Plan and Rehabilitation

Liposclerosing myxofibrous tumor is usually a slowly growing benign lesion. Some cases can be managed conservatively under imaging surveillance. Key points in treatment and rehabilitation include:

1. Conservative Management:
   • For patients with no significant or mild symptoms, regular observation may be considered. X-rays every 6 months and MRI or CT annually are recommended to monitor lesion progression.
   • If pain is significant, nonsteroidal anti-inflammatory drugs (NSAIDs) or appropriate analgesics may be used.
   • Pay attention to bone health (supplement calcium and vitamin D, and perform bone density tests as needed).
2. Surgical Treatment:
   • For patients with significant symptoms or those at increased risk of pathological fracture, curettage plus bone grafting or internal fixation may be performed. In cases of malignant transformation or extensive bone destruction, joint replacement may be necessary.
3. Rehabilitation and Exercise Prescription:
   • Engage in safe, low-impact exercise within tolerable limits, such as walking, swimming, and lower-limb strength training, to improve quadriceps strength and hip function.
   • Follow the FITT-VP principle:
     1. Frequency: 3–5 times a week, adjusted according to the patient’s physical condition.
     2. Intensity: Begin with low intensity (e.g., a 10–15-minute walk), gradually increasing to moderate intensity.
     3. Time: Start at 15 minutes per session and gradually extend to 30–45 minutes, based on pain and fatigue levels.
     4. Type: Opt for activities with less joint impact, such as stationary cycling, resistance band exercises for the lower limbs, swimming, or light resistance training.
     5. Progression: Increase duration or load gradually under safe conditions, avoiding overexertion.
   • If the patient has osteoporosis or cardiovascular comorbidities, assess safety first, possibly collaborating with rehabilitation or cardiology specialists to devise an individualized exercise plan.
   • Monitor pain and fatigue levels closely. If severe pain or discomfort arises, pause the activity and seek medical evaluation.

Disclaimer: This report provides a reference analysis based on the available imaging and clinical information. It does not replace an in-person consultation or professional diagnosis and treatment. If you have any questions or changes in your condition, please consult an orthopedic or related specialist promptly.