Medial Collateral Ligament (MCL) Sprain: This is a common injury in children and adolescents, especially with twisting mechanisms. The MCL is more susceptible to injury due to its anatomical location and the forces applied during a twisting injury.

Anterior Cruciate Ligament (ACL) Sprain: Although less common in pre-adolescent children due to open growth plates, ACL injuries can occur, especially with significant twisting forces.
Meniscal Tear: The menisci can be injured with twisting motions, and this diagnosis should be considered, especially if there is locking or catching of the knee.
Osteochondritis Dissecans: This condition involves a fragment of cartilage and bone becoming detached, often due to repetitive stress or a single traumatic event, and can present with knee pain after a twisting injury.

Fracture (e.g., Tibial Spine Avulsion Fracture): Although less common, fractures around the knee can occur with significant trauma and must be ruled out to avoid missing a potentially serious condition.
Septic Arthritis: This is an infection within the joint space, which is a medical emergency. While less likely, it must be considered, especially if there are signs of infection such as fever, redness, or significant swelling.
Osteonecrosis: This condition involves the death of bone tissue due to a lack of blood supply and can be a complication of certain fractures or severe injuries.

Discoid Meniscus: An abnormal formation of the meniscus that can lead to knee pain and instability, which might be uncovered after a twisting injury.
Patellar Dislocation: Although more commonly associated with direct blows to the knee, a patellar dislocation could potentially occur with a severe twisting mechanism.
Growth Plate Fracture: In children, growth plates are weaker than the surrounding bone and ligaments, making them susceptible to injury. A twisting mechanism could potentially lead to a fracture through a growth plate.