Posterior Tibial Tendon Dysfunction

Wikis > Orthopaedics > Posterior Tibial Tendon Dysfunction

Posterior Tibial Dysfunction:
http://www.podiatrytoday.com/article/305

Often missed as a diagnosis.
Causes significant and progressive pain and development of a flat pronated foot  can become very debilitating. Commonest cause of acquired flatfoot in adults.

Aetiology:
4 Categories of aetiology :
Type 1 – Direct injury to posterior tibial tendon  dysfunction
Type 2 – Pathologic rupture (eg in rheumatoid arthritis) – also associated with diabetes, hypertension and obesity
Type 3 – Idiopathic rupture (cause of rupture unknown)
Type 4 – Functional rupture (tendon intact, but not functioning)
Pre-existing pronated or flatfoot may be a factor.

Pathogenesis:
Dysfunction of posterior tibial tendon  cannot provide supination force medial to subtalar joint axis  increased pronation at subtalar joint  subtalar joint axis becomes more medially deviated  less lever arm for what remains of posterior tibial function  progressive deformity.
Also get pathologic lengthening of spring ligament  less able to resist plantarflexion and adduction of head of talus  progression of deformity
Degenerative changes occur within the tendon

Clinical Features:
Due to progressive nature and potential disability  early detection is important. Onset usually insidious – with diffuse (often intermittent) ankle pain. Occasionally onset is sudden.
Generally get tenderness and oedema along tendon (often poorly localised) – usually from medial malleolus to navicular tuberosity (most hypovascular area of tendon) – may be located to sinus tarsi. Trigger points may be present.
First Metatarsal Rise Sign
Foot is pronated, arch lowered, rearfoot everted, forefoot abducted – patient may have noted a progression of this. Patients may complain of increased fatigue.
Heel on affected side does not generally invert during heel raise test – doing 10 or more single limb heel raise tests to fatigue muscle may show limited inversion on heel raise.
Muscle testing  weakness

Classification/Staging:
Stages of posterior tibial dysfunction :
Stage: Pre-stage 1 Stage 1 Stage 2 Stage 3
Condition: Tibialis posterior myofascial tightness Peritendonitis, tenosynovitis, tendinosis, paratendonitis Tendon elongation, partial tendon tear Complete tendon tear
Significant findings: Tendon neither swollen or tender.
Rearfoot neutral or inverted.
Single heel raise is less then the non-impaired side and heel lacks calcaneal inversion.
Tibialis posterior length test is positive.
Tender trigger point(s) in muscle(s). Tendon swollen and tender.
Rearfoot neutral or slightly everted.
Single heel raise is less than non-impaired side and lacks calcaneal inversion.
Tibialis posterior length test cannot be tested due to pain.
Tender trigger point(s) in muscle. Tendon swollen and tender.
Rearfoot everted.
Single heel rise is less than non-impaired side and heel lacks calcaneal inversion.
Tibialis posterior length test cannot be tested due to pain.
Tender trigger point(s) in muscle. Tendon swollen and tender.
Rearfoot everted, severely flat foot.
Single heel raise cannot be performed.
Tibialis posterior length test cannot be performed due to pain.
Tender trigger point(s) in muscle.
Positive “too many toes” sign.

Management:
Patient education re progressive nature is important.
Reduce pain – activity modification/ice/NSAID’s
Weightbearing cast if severe (8-12 weeks)  orthoses after casting
Orthoses essential – may need to be aggressive due to medial location of STJ axis (more rigid; minimal arch fill; wide orthoses; medial heel skive; or inverted device)
Basketball/hiking boots/high top boots  further help increase supination force medial to STJ axis.
Physical therapy – especially muscle strengthening and range of motion activities

If above unsuccessful:
 Brace with double steel uprights with a medial T strap
 Surgery (<5%)

Comments are closed.