1. Radiological Findings

Based on the provided X-ray images of the pelvis and bilateral femurs:

• On the right proximal femur, internal fixation hardware (intramedullary nail) from previous surgery is visible. Its position and shape indicate good postoperative reconstruction, and signs of fracture healing can be observed.
• In the left proximal femur, a fracture line is also noted, originating from the lateral cortex and running transversely (or nearly transversely). It extends medially in an oblique pattern, with a “spike-like” appearance at the medial bony end.
• There is no obvious comminution of the fracture segment, and varying degrees of cortical thickening are observed.
• This type of fracture is located in the femoral shaft near the subtrochanteric region, consistent with a “subhip” or “subtrochanteric–proximal femoral shaft” characteristic.
• Combined with the medical history, multiple bilateral fractures in similar locations of the proximal femur are noted.

Overall imaging findings suggest that the left femur exhibits a typical subhip transverse-to-oblique fracture trajectory with lateral cortical thickening, consistent with the characteristics of an Atypical Femoral Fracture (AFF).

2. Potential Diagnoses

Based on the patient’s history (over 10 years of bisphosphonate use, bilateral femoral fractures in similar locations) and imaging findings, possible diagnoses or differential diagnoses include:

1. Atypical Femoral Fracture (AFF)
   Reason: Long-term bisphosphonate use, fracture site typically in the proximal femoral shaft, transverse pattern on the lateral cortex extending obliquely to the medial side, and minimal trauma associated with the fracture occurrence, all consistent with the revised ASBMR criteria.
2. Osteoporotic Fracture
   Reason: The patient is elderly with a history of osteoporosis. However, common sites of osteoporotic fractures typically include hip intertrochanteric fractures or vertebral compression fractures. The characteristic subhip transverse fracture must be differentiated from AFF.
3. Pathological Fracture (e.g., metastatic lesion)
   Reason: The patient also has multiple chronic conditions (diabetes, rheumatoid arthritis, etc.). If there is a potential malignancy or bone metastasis, it could result in pathological fractures. Nevertheless, from the imaging, no obvious osteolytic or osteoblastic tumor features are observed.

3. Final Diagnosis

Based on:

• The patient’s age and medical history (particularly prolonged bisphosphonate use).
• Similar fracture patterns in the proximal femoral shaft on both sides, with a transverse-to-oblique configuration.
• Fractures occurring under minimal or no apparent trauma.
• Cortical thickening visible at the fracture site on imaging, with a relatively regular fracture line and a medial spike.

Overall, the most likely diagnosis is: Atypical Femoral Fracture (AFF).

If uncertainty remains, MRI or bone scintigraphy can be performed to rule out potential neoplastic processes, and bone metabolic markers or laboratory tests can be used to comprehensively assess bone turnover status.

4. Treatment Plan and Rehabilitation

1. Treatment Strategy
   • Surgical Fixation: For patients with complete fractures, intramedullary nail fixation is the main approach. For those without a complete fracture but at high risk (presenting as an incomplete fracture with significant cortical thickening or pain), prophylactic nailing can be considered.
   • Medication Adjustments: Depending on the patient’s bone status and duration of bisphosphonate therapy, consider discontinuing or replacing bisphosphonates, for instance, switching to alternative anti-osteoporotic treatments (e.g., teriparatide, selective estrogen receptor modulators). This should be done under the guidance of an endocrinologist or osteoporosis specialist, with monitoring of bone mineral density and bone turnover markers.
   • Other Supportive Treatments: Supplement calcium and vitamin D, and control blood glucose, blood pressure, and rheumatoid arthritis if necessary. Be mindful of psychological status (including depression) and provide psychological interventions as needed.
2. Rehabilitation/Exercise Prescription Recommendations (FITT-VP Principle)
   • F (Frequency): In the early phase of fracture healing (6–8 weeks postoperatively), follow postoperative instructions to undertake 3–5 rehabilitation sessions per week, avoiding excessive weight-bearing. In later stages, gradually increase to once-daily low-impact exercise.
   • I (Intensity): Start with light training, avoiding sudden or intense weight-bearing activities. Use small-range movements (e.g., sit-to-stand exercises, walking with a walker or rail support). Rest promptly if significant pain or fatigue occurs, and gradually increase intensity.
   • T (Time): Begin with 10–15 minutes per session and gradually extend to 20–30 minutes as tolerated, splitting the sessions to prevent excessive fatigue.
   • T (Type): Focus on range-of-motion exercises and muscle strength recovery in the early stages. In the mid-to-late stages, gradually incorporate endurance training, such as light lower-limb cycling or stationary biking, and other low-impact activities.
   • V (Volume): Increase exercise volume progressively, adjusting weekly based on healing status and pain levels.
   • P (Progression): As the fracture heals and lower-limb strength recovers, progressively increase the difficulty level, for example, transitioning from a walker to crutches, and eventually to a single cane.

   During rehabilitation, it is crucial to prevent further falls or fractures; seek guidance from a professional rehabilitation therapist if necessary.

Disclaimer: This report is a reference analysis based on existing information and does not replace an in-person consultation or professional orthopedic guidance. If you have any doubts or experience worsening symptoms, please seek medical attention promptly.