Final answer:
A positive McMurray's test suggests damage to the meniscus of the knee, providing a diagnostic indication of a potential tear in the meniscus, specifically pointing to the medial meniscus when considered in context with common knee injury patterns.
Step-by-step explanation:
A positive McMurray's test suggests injury to the meniscus of the knee. This diagnostic test involves the physician manipulating and bending the knee, then straightening and twisting it, to identify the presence of pain or a clicking sound which indicates a tear in the meniscus. Based on the information provided, a strong blow to the lateral side of the extended knee can result in a sequence of injuries starting with the tearing of the tibial collateral ligament, followed by damage to the medial meniscus, and finally the rupture of the anterior cruciate ligament. This sequence demonstrates that the medial meniscus, which is attached to the tibial collateral ligament, can be easily damaged during knee injuries, and thus a positive McMurray's test would most notably suggest injury to this structure - specifically damage to the medial meniscus.