1. Imaging Findings

Based on the provided hip X-ray and MRI images, a space-occupying lesion is observed in the left proximal femur trochanteric region (between the femoral neck and the trochanter), presenting as follows:

• X-ray: The lesion appears as a focal radiolucent area with relatively clear margins, showing a thin sclerotic rim (“thin sclerotic border”). Small spot-like or fine granular calcifications/ossifications can be seen internally.
• MRI: On T1-weighted images, the lesion signal is generally isointense to the surrounding muscle (“isointense”). On T2-weighted images, it appears predominantly hyperintense, with areas of low signal corresponding to sclerotic or calcified components. The overall boundaries remain relatively clear, with no noticeable soft tissue invasion.

No clear sign of swelling is observed in the surrounding soft tissue. The joint alignment is normal, and there is no obvious destruction of the surrounding bone structures. The patient reports prolonged pain (3 months) without a history of acute trauma.

2. Possible Diagnoses

Considering that the patient is a middle-aged (53-year-old) female with persistent pain in the left trochanteric region and based on the imaging characteristics, the following diagnoses or differential diagnoses are considered:

1. Liposclerosing Myxofibrous Tumor (LSMFT)
   • Commonly seen in the proximal femur trochanteric area, containing various pathological components (fat, fibrous tissue, myxoid tissue, etc.). Imaging typically shows a radiolucent lesion with a sclerotic rim and internal calcifications.
   • Usually benign, but there is an approximate 10-16% risk of malignant transformation.
2. Fibrous Dysplasia or Fibrous Lesions
   • These lesions may present as well-defined radiolucent areas, sometimes with sclerosis. However, they are typically less complex in terms of location and histological patterns compared to LSMFT.
3. Bone Fibroma, Enchondroma, or Other Benign Bone Tumors
   • They can also manifest as radiolucent lesions, possibly with a thin sclerotic rim or focal calcifications. Distinguishing characteristics revolve around typical locations and imaging structures.

3. Final Diagnosis

Based on the patient’s age range (commonly occurring in the 4th to 6th decades of life), the typical location in the proximal femur trochanteric region, and the mixed features on X-ray and MRI (radiolucency, sclerosis, calcification), along with the patient’s persistent local pain, the most likely diagnosis is:

Liposclerosing Myxofibrous Tumor (LSMFT).

This condition requires close monitoring and vigilance for potential malignant transformation. If symptoms are significant or there is notable progression and increased pain, a biopsy should be considered to assess the benign or malignant nature of the lesion.

4. Treatment Plan and Rehabilitation

• Treatment Strategy:
  • Close Observation: For patients with mild or negligible symptoms, regular follow-up (routine MRI or X-ray) can be carried out to monitor any changes in the lesion.
  • Biopsy and Surgery: For patients with significant pain or lesions suspected to be malignant, a core needle biopsy is recommended to confirm the diagnosis. If the pathology indicates a risk of malignancy or local structural compromise, surgical interventions such as curettage, segmental resection, or prosthesis replacement may be considered.
  • Multimodal Management: Depending on the histological findings and surgical outcomes, radiotherapy and chemotherapy can be combined if malignant or highly suspicious features are present.
• Rehabilitation and Exercise Prescription:
  • Early Phase (Preoperative or Non-operative Stage):
    • Focus on protecting the affected limb and relieving pain, avoiding strenuous weight-bearing activities.
    • Perform low-load active exercises targeting hip joint range of motion, such as seated or supine hip flexion/extension (10-15 repetitions, 2-3 sets per day).
    • Maintain lower-limb muscle strength by light resistance exercises such as straight leg raises (10 repetitions, 2-3 sets per day).
  • Intermediate Phase (Postoperative or Stable Observation without Progression):
    • As long as there is no significant pain, gradually restore joint mobility and lower-limb strength with exercises like wall-sitting or elastic band resistance training.
    • Recommend 3-4 training sessions per week, each lasting about 20-30 minutes; adjust the intensity based on pain and fatigue.
  • Late Phase (Stable or Advanced Rehabilitation):
    • Progressively incorporate aerobic exercises (e.g., walking on level ground, cycling, swimming), gradually increasing intensity and duration.
    • Follow the FITT-VP principle: start with low intensity (around 50-60% of maximal heart rate), then increase intensity by about 5-10% weekly and add 5 minutes of exercise time as tolerated, while avoiding excessive impact on the hip.
  • Individual Precautions:
    • If the lesion compromises the bone structure, prevent falls and high-impact trauma to avoid further injury.
    • Consider assistive devices (e.g., cane, walker) if necessary for protection and support until bone integrity is ensured.

Disclaimer: This report represents a reference analysis based on the available information. It is not a substitute for an in-person consultation or professional medical advice. If you have any concerns or if your condition changes, please seek medical attention promptly for further evaluation and treatment.