Occult Femoral Neck Stress Fracture Presenting as Knee Pain: A Diagnostic Challenge in Primary Care

Femoral neck stress fractures (FNSFs) are uncommon injuries that may present with atypical and misleading symptoms, resulting in delayed diagnosis. Although classically associated with athletes and military personnel, these fractures can also occur in non-athletic individuals exposed to repetitive mechanical stress. We report the case of a 35-year-old male who presented with isolated knee pain without antecedent trauma. Initial clinical evaluation suggested primary knee pathology, and knee radiographs were unremarkable. Persistent symptoms and abnormal findings on hip examination prompted extension of the diagnostic workup to the hip. Magnetic resonance imaging (MRI) revealed an occult nondisplaced compression-side femoral neck stress fracture. The patient was managed conservatively with protected weight-bearing and close orthopaedic follow-up, resulting in complete recovery. This case highlights the importance of considering proximal sources of pain when evaluating unexplained knee symptoms. MRI is particularly useful when persistent symptoms and examination findings raise suspicion for occult proximal pathology despite negative radiographs.Subject AreasOrthopedics