Final answer:
Contracted hip flexors are indicated by the inability to fully extend the hip rather than a fixed degree of hip flexion. Physical examinations like the modified Thomas test are used to detect tightness of hip flexors.
Step-by-step explanation:
A positive sign of contracted hip flexors is generally indicated by reduced hip extension rather than a specific degree of hip flexion. During a physical examination, if the thigh lifts off the table when the opposite leg is brought into full extension (a modified Thomas test), this can suggest tightness of the hip flexors. In clinical practice, there isn't a universal degree of hip flexion that signifies contracted hip flexors; rather, the focus is on the inability to fully extend the hip. The degree of restricted extension is more indicative of hip flexor tightness than a specific degree of flexion.
For example, if a person with contracted hip flexors tries to extend their leg backward while standing, they will only be able to reach a maximum of about 120 degrees of hip flexion.Contracted hip flexors can result from tightness or weakness in the muscles, and can be addressed through stretching and strengthening exercises.