Orthopedic Exam / Special Tests for Physical Therapy: Leg and Ankle
The triceps surae aka “three-headed [muscle] of the calf” is a pair of muscles located at the calf – the two-headed gastrocnemius and the soleus. These muscles both insert into the calcaneus, the bone of the heel of the human foot, and form the major part of the muscle of the posterior leg, commonly known as the calf muscle. The triceps surae is connected to the foot through the Achilles tendon, and has 3 heads deriving from the 2 major masses of muscle.
The superficial portion (the gastrocnemius) gives off 2 heads attaching to the base of the femur directly above the knee. The deep (profundis) mass of muscle (the soleus) forms the remaining head which attaches to the superior posterior area of the tibia.
Special Test: Thompson’s Test / Simmond’s Test
- to test for 3rd degree strain or rupture of the Achilles tendon
- Patient is prone , feet over the edge of the table, legs relaxed
- Squeeze the affected gastrocnemius and soleus muscles
- Absence of plantarflexion when the muscles are squeezed
** When the achilles tendon is intact and the calf is squeezed, the ankle will plantar flex .
** It is still possible for the m. plantaris and deep toe flexors to also provide plantar flexion even if the Achilles tendon is ruptured. To be sure that the patient has a complete Achilles tendon rupture, there are three additional clinical signs that may be observed to corroborate the diagnosis
** On careful inspection, with the patient prone and both ankles fully relaxed, the foot on the ruptured side hangs straight down due to the absence of the tendon tone
There may be a palpable gap in the tendon, approximately 3-6cm proximal to the insertion into the calcaneus.
** The strength of the plantar flexion is markedly reduced