Differential Diagnosis for Flank Pain and Pain on Hip Flexion
Single Most Likely Diagnosis
- Lumbar nerve root compression: This is the most likely diagnosis due to the symptoms of flank pain and pain on hip flexion, which are commonly associated with lumbar radiculopathy, particularly involving the L2-L4 nerve roots. These roots can refer pain to the flank area and hip.
Other Likely Diagnoses
- Lumbar spinal stenosis: This condition can cause pain in the lower back, flanks, and hips, especially with activities that involve flexion or extension of the spine. The symptoms can be exacerbated by walking or standing and relieved by sitting or flexing forward.
- Thoracic nerve root compression: Although less common than lumbar nerve root compression for these specific symptoms, thoracic radiculopathy can cause flank pain, especially if the upper lumbar or lower thoracic nerve roots are involved.
- Hip pathology (e.g., hip arthritis, trochanteric bursitis): Conditions affecting the hip can cause pain that radiates to the flank area or is exacerbated by hip flexion.
Do Not Miss Diagnoses
- Abdominal aortic aneurysm: A potentially life-threatening condition that can cause flank pain. Although it might not typically cause pain on hip flexion, the severity of the condition warrants its consideration in the differential diagnosis.
- Renal colic or kidney stones: Severe, sharp pain in the flank that can radiate to the groin, which might be exacerbated by movement, including hip flexion.
- Inflammatory or infectious processes (e.g., pyelonephritis, discitis, osteomyelitis): These conditions can cause severe pain and have significant implications if not promptly diagnosed and treated.
Rare Diagnoses
- Referred pain from intra-abdominal pathology (e.g., pancreatic cancer, gallbladder disease): Certain intra-abdominal conditions can cause referred pain to the flank area, although these would be less common causes of pain on hip flexion.
- Psoas abscess or hematoma: Conditions affecting the psoas muscle can cause flank and hip pain, especially with flexion of the hip.
- Neoplastic processes (e.g., metastatic disease to the spine or soft tissues): Although rare, tumors can cause a wide range of symptoms, including flank pain and pain on hip flexion, depending on their location and involvement of surrounding structures.