Final answer:
Improperly applied plaster or pressure from a cast can cause pain, improper healing, and Volkmann's ischemic paralysis, which entails muscle paralysis and contracture due to lack of blood flow.
Step-by-step explanation:
Improperly applied plaster or subsequent swelling that produces pressure of the cast against underlying soft tissues could cause all of the above, meaning it can lead to pain, improper healing, and Volkmann's ischemic paralysis. Volkmann's ischemic paralysis is a condition that occurs when there is a lack of blood flow (ischemia) to the forearm muscles, leading to paralysis and contracture of the muscles. This condition can be a complication of an improperly managed fracture or cast. Padding a strained muscle and ensuring proper alignment and pressure distribution during healing is crucial to prevent such complications.