Conducting A Quick And Easy Functional Lower Extremity Exam Of An Athlete
The patient stands with his or her feet shoulder width apart. Then the patient transfers weight to one leg and balances on that leg while raising the non-weightbearing leg and bending the knee and hip 90 degrees. To add a dynamic component, the patient can swing the non-weightbearing leg in the sagittal plane. The patient should hold the position for 10 seconds with the eyes both open and closed.8
Look for poor balance, flailing arms, changing foot position, pelvic drop or slouching upper body posture. Compare static and dynamic balance. Many athletes will perform perfectly in the static exam and fail miserably when challenged with the dynamic component.
Key Insights On Ankle ROM Tests
As podiatrists, we are keenly aware that restricted ankle motion is a risk factor in both acute and overuse sports injuries.9-11
Differentiating between gastroc equinus and osseous equinus best occurs with a static exam and X-ray. One can quickly test functional ankle ROM with the lunge test, popularized by Bennel and coworkers.12 In this test, the patient stands with the toes 10 cm from a wall. Then flex the knee and dorsiflex the ankle to bring the knee as close to the wall as the patient can without lifting the heel. Measure the angle of the tibia in relation to the ground at a point 15 cm distal to the tibial tuberosity. Normal ankle ROM is 35 degrees or better.
Another way to assess functional ankle ROM is with the deep squat. This test assesses not only the ankle but also the knees and hips for bilateral symmetric mobility.2 The patient stands with feet shoulder width apart and parallel to the sagittal plane. The patient then descends slowly into as deep of a squat as he or she can perform while keeping the heels on the floor, and his or her head and chest upright and facing forward. Observing from the front, the examiner looks for valgus collapse of the feet or knees and external rotation of the lower leg as signs of poor function. Observing from the side, the examiner sees if the thigh is parallel to the floor (or better) and/or if the butt is lower than the knees. Failure to get the butt low can indicate inadequate ROM.
Essential Pointers On Foot Intrinsic Muscle Strength/Activation
Manual muscle testing is an accepted part of the patient exam and provides information on the large extrinsic muscles of the foot and ankle complex. However, it is more difficult to isolate and test the smaller intrinsic muscles of the foot. Just as inhibition in activation of the gluteus medius muscle has been implicated in poor dynamic locomotor control of knee and hip, some speculate that inhibition of the intrinsic foot muscles may negatively affect gait and balance.13 Mann and Inman wrote that the intrinsic foot muscles “… play the principal active role in the stabilization of the foot during propulsion.”14 They also wrote that the pronated foot requires greater intrinsic muscle activity to stabilize the subtalar and midtarsal joints than does the normal foot. When running, the foot is in contact with the ground for 0.1 to 0.4 seconds. If there is any latency or inhibition of the intrinsic foot muscles, then the dynamic stability of the foot is compromised.
For the test, the patient stands evenly weighted with legs shoulder width apart. Then the patient presses the hallux to the ground while elevating and extending the lesser digits. If the flexor hallucis brevis is activated, the patient can do this movement quickly and in a smooth coordinated manner with no movement of the lower leg or rearfoot. If the muscle is inhibited, the patient will struggle, often everting the knee and rearfoot while recruiting the extrinsic muscles to compensate for the latency of the flexor hallucis brevis.15,16