What does a navicular drop measurement of 10mm or more indicate?

A navicular drop measurement of 10mm or more is indicative of hyperpronation. This condition suggests that the foot is excessively rolling inward during weight-bearing activities, which can lead to complications such as altered biomechanics and increased risk of injuries. The navicular bone is a key structure in the foot that plays a significant role in arch support and stability during movement. When the navicular drops significantly, it highlights a collapse of the foot's arch, characteristic of hyperpronation.

This weakened arch can affect the alignment and function of the entire lower extremity, which may contribute to sports-related injuries or discomfort, particularly in the lower back, knees, and hips. Hyperpronation is often a focus in athletic training and rehabilitation, as understanding foot mechanics is crucial for preventing injuries and optimizing performance.

In contrast, the other choices refer to different conditions. Metatarsalgia is concerned with pain in the metatarsals, supination refers to the outward rolling of the foot, and pes cavus pertains to a high arch formation, none of which are directly associated with a navicular drop measurement of 10mm or more. Therefore, hyperpronation is correctly identified as the condition indicated by that specific measurement.