Tibialis Posterior Muscle
Action – plantar flexion and inversion of the foot
– Plantar flexion – pointing the foot and toes away from the knee
– Inversion – the foot moves towards the side of the big toe
Origin – posterior proximal 2/3 of tibia, fibula and interosseous membrane
Insertion – fans out over the plantar surface of foot (navicular, all 3 cuneiforms, 2nd-4th metatarsals, cuboid and calcaneus)
Nerve – tibial nerve (L4-S1)
Tibialis posterior is located on the back of the lower leg deep to the main ‘calf’ muscles (gastrocnemius and soleus), so it can be difficult to feel.
It helps to stabilise the ankle and prevents over-pronation while walking, as well as supporting the arch of the foot. Playing an important role in running for both ankle stability and spring in the foot. For those with ‘flat feet’ and/or wearing orthotics, tibialis posterior strengthening is recommended for the support of the arch.
If you stand on your toes or use your foot to press on the pedals in your car, then you are engaging tibialis posterior.
Dysfunction in the muscle, similar to tibialis anterior, can cause pain around the shin bone (Medial Tibial Stress Syndrome), in the front of the ankle or the big toe (shown in the above referral pattern image). Shin splints are an overuse or overload injury that can involve inflammation and pain in tibialis posterior and along the Tibia where the muscle inserts. Weakness can lead to the arch of the foot collapsing, resulting in pain and increased stress on the muscle.
When inflamed it can be extremely painful to massage. Dry needling is a good option if this is the case.
As usual, consult your local Myotherapist on what strategy may work best for your situation.
Stand with feet hip width apart. Place a tennis ball (or yoga block, foam roller) between both ankles and squeeze the heels together to hold on to it. While keeping the squeeze, raise the heels off the ground as high as you can, hold for 1-2 seconds and slowly lower back down. Repeat 10-15 times.
Sit on the floor with the affected leg straight out in front of you, placing a rolled up towel under the knee so that it is slightly bent. Use another towel, belt or strap looped around the foot (or simply your outstretched hand on the same side), pull the top of the foot towards the knee while everting the foot (so the small toe side comes a little further than the big toe side). You should feel a stretch deep in your calf. Hold for 20-30 seconds.
Sitting in a chair, place your ankle of the affected leg on your opposite knee. Place your thumbs on the inside edge of the tibia. Anywhere in the top 2/3 of your tibia. Push in and around to the back of your tibia with your thumbs.
Flex and extend your foot as you push in. You will be able to feel the muscle contract if you are on the correct spot. If you feel a pulse move onto another spot.
As always, consult your local Myotherapist to make sure the above techniques are suitable for your situation.
Contributors: Ben Lewis & Jesse Kingsbury