Meralgia Paresthetica: This condition is characterized by numbness, tingling, and burning pain in the outer part of the thigh due to compression of the lateral femoral cutaneous nerve. However, given the inner thigh involvement, it's less likely but still considered due to the proximity and potential for nerve entrapment or irritation in the region that could radiate or refer pain to the inner thigh.

Adductor Strain: A common injury in athletes, especially those involved in sports that require quick changes of direction, such as soccer or hockey. The adductor muscles are located in the inner thigh, and strain or pull can cause pain that worsens with walking or physical activity.
Osteitis Pubis: An inflammatory condition affecting the pubic bone and surrounding structures, often seen in athletes. It can cause pain in the groin area that may radiate to the inner thigh, especially with weight-bearing activities like walking.
Stress Fracture of the Pubic Ramus or Femur: Overuse injuries that can cause pain in the groin or thigh area, which may worsen with activity such as walking.

Aortic Aneurysm or Aortic Dissection: Although less common and typically presenting with severe, tearing chest or back pain, in rare cases, an aortic dissection can cause referred pain to the groin or thigh due to the involvement of the iliofemoral arteries. This is a medical emergency.
Deep Vein Thrombosis (DVT): Can cause pain and swelling in the leg, which might be exacerbated by walking. While DVT typically presents with more pronounced swelling and warmth, it's crucial not to miss due to the risk of pulmonary embolism.
Herniated Lumbar Disc: Specifically, an L2-L3 or L3-L4 disc herniation can cause radiculopathy that might refer pain to the inner thigh. This condition can significantly impact quality of life and may require urgent intervention if there are signs of neurological compromise.

Avulsion Fracture of the Lesser Trochanter: A rare injury where a fragment of bone is pulled off by the attached muscle (usually the iliopsoas), which can cause pain in the thigh.
Neurogenic Tumor: Rare tumors arising from the nerves, such as neurofibromas or schwannomas, which can compress nearby structures and cause pain.
Intra-abdominal or Pelvic Pathology: Conditions like an intra-abdominal shunt infection, appendicitis, or ovarian torsion can cause referred pain to the thigh, although these would typically be accompanied by other significant symptoms.