Final answer:
A lateral blow to the knee can damage the tibial collateral ligament, medial meniscus, and anterior cruciate ligament, an injury sequence known as the "terrible triad." Tight casts can also induce similar damage if not applied correctly.
Step-by-step explanation:
A lateral blow to the knee can cause a series of injuries primarily affecting the tibial collateral ligament, the medial meniscus, and the anterior cruciate ligament. This severity of injury is referred to as the "terrible triad" injury. The tibial collateral ligament, being attached to the medial meniscus, is particularly vulnerable as it can cause damage to both the ligament and the meniscus. The anterior cruciate ligament can also rupture in this type of injury, especially if the blow is strong and the knee is extended at the time of impact.
Aimed at prevention and aftercare, it's essential for tight casts around the knee to be well-fitted to avoid putting excessive pressure on the ligaments and surrounding structures that might lead to complications similar to those caused by a lateral blow.