Abstract: Atypical subtrochanteric and diaphyseal femoral fractures (AFF) have been suggested to be associated with the use of bisphosphonates (BPs), but the role of these drugs is still under debate. A 64-year old female, never treated with BPs was admitted to our Rehabilitation Institute because of a recent right AFF. The patient began suffering from low back pain radiating to the groin and to the anterior regions of the right thigh and leg, A nuclear magnetic resonance (NMR) of the lumbar spine showed disc protrusions at the L3-L4 and L5-S1 levels with impingement of the spinal nerve root. Therefore she was treated with analgesic, anti-inflammatory and muscle relaxing compounds for nine months without reduction of symptoms. Being the pain still present, the patient felt down the street breaking the right femoral neck and the femoral distal shaft. Following the ASBMR criteria the fracture was classified as a complete AFF and the patient underwent surgical ostheosynthesis with nail. A bone biopsy of the fracture site was performed showing findings consistent with B-cells non-Hodgkin lymphoma (NHL). Immuno-histochemical analysis highlighted that the atypical cells were follicolar G2 pattern diffuse large B cells.
Conclusions: AFF can occur also in patients not treated with BPs. In the present case report, the cause of the fracture was a NHL. Even uncommon, this occurrence should be considered in the differential diagnosis of radicular pain.
Keywords: Atypical femoral fracture,; Bisphosphonates; Non-Hodgkin lymphoma.