THE PODIATRIST’S ROLE IN THE ASSESSMENT OF THE SPORTS PATIENT:

PART 2 – GAIT ANALYSIS

MANJU MITAL, LECTURER AND STEVE AVIL, LECTURER

INTRODUCTION Gait is divided into a swing phase (no contact with the ground) and a stance phase (contact with the ground). The stance phase is further divided into contact, mid-stance and propulsion. Gait proceeds as follows: 1. Head/shoulders: no signs of excessive movement, tilt. 2. Pelvic rotation: downward (lateral) tilting of the non-weight-bearing swinging leg during single support phase, and transverse movement during double support. 3. Hip joint: the hip flexes about 30° at heel contact and is forced into extension during mid-stance and toe- off, as the knee and ankle plantarflex. 4. Knee joint: flexion of the knee provides the greatest degree of shock absorbency. Plantarflexion of the ankle at heel-strike forces the tibia forward, resulting in flexion of the knee. The quadriceps restrain rapid flexion, while the hamstrings prevent hyperextension. The knee then extends from mid- stance until heel-lift and flexes

This article analyses the walking and running gait and briefly discusses a number of treatment modalities. It also looks at the role of orthoses as part of the treatment protocol and looks at the relationship of lower-limb injuries with associated biomechanical abnormalities.

throughout propulsion. 5. Ankle joint: at heel-strike, the ground reaction force is directed behind the ankle. This places a vertical force on the heel at heel-strike, which results in rapid plantarflexion. At mid-stance, tibialis anterior, extensor digitorum longus and extensor hallucis longus eccentrically contract, the motion is resisted, and the ankle begins to dorsiflex with forefoot loading. Once the heel has lifted off the ground, knee flexion can occur, allowing the foot to plantarflex. At toe-off, contraction of the anterior muscle group initiates dorsiflexion of the ankle. 6. Subtalar joint (STJ): at heel contact, ground reaction forces pronate the STJ, allowing for weight transfer to the forefoot. During mid-stance, the STJ starts to supinate with external rotation of the tibia and continues until the swing

phase. Extensor digitorum longus activity causes the STJ to pronate in order to clear the ground. The anterior group of muscles then contract before heel contact in order to resupinate the STJ. 7. Midtarsal joint (MTJ): the forefoot is inverted around the long axis of the MTJ at heel-strike. 8. When the STJ is in neutral, the MTJ fully pronates and locks the forefoot on the rearfoot, by creating stability.

GAIT ANALYSIS OF RUNNING

An increase in pelvic, hip and knee rotations is seen in running due to an increase in joint movements. Slower running shows a heel-to-toe foot function. In a middle-distance runner, the forefoot may strike first and then the heel lowers before propulsion. In the sprinter, the forefoot is the main of contact from contact to toe-off (Fig. 1).

Figure 1: Gait during walking 24

WHAT DO THE PATIENT’S SHOES REVEAL? An assessment of the patient’s shoes is an integral part of the assessment and can help to confirm a diagnosis. Wear marks and patterns reveal information about foot function. It is normal for

sportEX medicine 2009;42(Oct):24-26