Muscle strain: This is the most common cause of thigh and groin pain, often resulting from overuse or direct injury to the muscles in the thigh or groin area. Activities that involve sudden stops, changes of direction, or direct blows to the area can lead to muscle strain.

Tendinitis: Inflammation of the tendons, which connect muscles to bones, can cause pain in the thigh and groin area. This condition is common in athletes who participate in sports that involve running, jumping, or quick changes of direction.
Osteitis pubis: This condition involves inflammation of the pubic bone and surrounding tissues, often seen in athletes who participate in sports that involve kicking, such as soccer.
Hernia: A hernia occurs when part of an intestine bulges through a weak area in the abdominal muscles, which can cause groin pain.
Bursitis: Inflammation of the bursae, fluid-filled sacs that cushion joints and reduce friction between bone and soft tissue, can cause pain in the thigh and groin area.

Testicular torsion: A medical emergency where the spermatic cord becomes twisted, cutting off the blood supply to the testicle. It requires immediate attention to save the testicle.
Femoral hernia: A type of hernia that occurs just below the inguinal ligament, where part of the intestine bulges through a weak area in the abdominal wall. It can lead to bowel obstruction or strangulation if not treated promptly.
Avascular necrosis of the femoral head: A condition where the blood supply to the head of the femur (thigh bone) is disrupted, leading to the death of bone tissue. It can cause severe pain and requires early diagnosis for effective treatment.
Deep vein thrombosis (DVT): A blood clot that forms in the deep veins of the body, which can cause pain, swelling, and warmth in the affected leg. It is a serious condition that can lead to pulmonary embolism if the clot breaks loose and travels to the lungs.

Piriformis syndrome: A condition where the piriformis muscle, located in the buttock region, compresses or irritates the sciatic nerve, causing pain in the thigh and groin area.
Meralgia paresthetica: A condition characterized by numbness, tingling, and burning pain in the outer part of the thigh, caused by compression of the lateral femoral cutaneous nerve.
Osteonecrosis of the femur: A rare condition where a portion of the femur dies due to lack of blood supply, often caused by trauma, steroid use, or excessive alcohol consumption.
Tumors: Both benign and malignant tumors can cause thigh and groin pain, although they are rare causes of this symptom.