Assessing and Progressing Achilles Isometrics in the Clinic

Peter starts most Achilles patients in a Smith machine, testing how much weight they can hold for 20 seconds in full plantar flexion, plantargrade and about 10 to 15 degrees of dorsiflexion, and how painful each position is. Inner range weakness is common. Full dorsiflexion is avoided at this stage because it is provocative and tests passive structures rather than strength. Weaker patients can start on a leg press, seated calf raise or assisted standing with scales under one foot. One isometric is used as the repeated assessment and the hold positions become the rehabilitation. Once the patient is confident, push isometrics are tested seated in plantargrade on a force plate or frame, where athletes should reach about two times body weight. Standing pushes are used for rehabilitation, dosed as 3 to 5 second maximal pushes, four repetitions, two minutes rest, three sets. The final stage is a standing push in near full dorsiflexion. Hip rotation, deeper dorsiflexion or an eversion wedge can bias different subtendons and the tibialis posterior.