After putting POP cast for supracondylar fracture a child developed severe pain over forearm. He is unable to move the fingers fully. He says this pain is terrible than the pain of the fracture. Volkmann's ischemia is suspected. The muscle which is affected by Volkmann's ischaemia most commonly is:

Volkmann's ischaemia is an ischemic injury to the muscles and nerves of the flexor compament of the forearm. This occurs due to the occlusion of the brachial aery following a supracondylar fracture. The muscles supplied by the anterior interosseous aery are most susceptible to ischemic damage because this aery is an end aery. Most commonly affected muscles are the flexor pollicis longus and flexor digitorum profundus (medial-half). Severe pain will be present over forearm usually over the flexor aspect of the forearm when the fingers are extended passively. Ischemic pain is much severe than the pain due to the fracture. Ref: Essential Ohopaedics by Maheshwari, 3rd edition, Page 83-84.