Introduction to surgery of the foot and ankle Flashcards
Why is the foot important?
To ensure that we have a smooth gait cycle
If foot anatomy is abnormal foot function is compromised
List the 3 sections of the foot
hindfoot, midfoot and forefoot
What does the hindfoot normally have?
Valgus
What are the aims of treating foot and ankle pathology?
Is always to achieve a foot which is :
- Painless - Plantigrade - Structurally normal - Functionally normal
Describe the achilles tendon
Also known as the heel cord The gastrocnemius, soleus and plantaris muscle unites to form a band of fibrous tissue which becomes the Achilles tendon which attaches to the calcaneal tuberosity Largest and strongest tendon Approximately 15 cm in length Plantarflexor of the foot
Why is the achilles tendon vulnerable to pathology?
Unlike other tendons it has no tendon sheath
It is surrounded by a paratenon
It has a poor blood supply
i. Posterior tibial artery ( proximal and distal section)
ii. Peroneal artery ( supplies midsection)
Blood vascularity weakest at the bone –tendon interface
Blood supply weakest at 2 to 6 cm form the calcaneal attachment
When does achilles rupture occur?
Occurs after a sudden forced plantarflexion to the foot
Violent dorsiflexion in a planatar flexed foot
Usually ruptures 4 to 6 cm above the calcaneal insertion in the hypovascular region
How is Achilles rupture treated?
In Functional bracing Surgery End to end repair VY advancement Failure to heal- Tendon transfer
Which tendon is used to treat achilles tendon
FLEXOR HALLUCIS LONGUS
Describe the surgical approach to the achilles tendon
Patient is prone or in lazy lateral position
Landmarks: The malleoli and the Achilles tendon- which is easily palpable
Incision: Longitudinal – slightly medially based ( but can go laterally as well)
Structure to avoid : Sural nerve laterally
Avoid going medial to Flexor hallucis longus (FHL) ( easily identifiable as has muscle fibres at this level ) - NEUROVASCULAR BUNDLE MEDIALLY
Describe the tibialis posterior tendon
Posterior aspect of interosseous membrane, fibula and tibia and has 9 insertions in the foot
Action-
Plantarflexes the ankle joint
Principal invertor of the foot
Adducts and supinates the foot
Arterial supply form the Posterior tibial, peroneal and sural nerve
Has a watershed area around the medial malleoli
What is the function of tibialis posterior
Stabilise lower leg
Facilitates foot inversion
Supports the foot’s medial arch
Plays a critical role in hindfoot inversion during the gait cycle
How does tibialis posterior insufficiency present?
Post-malleolar pain Arch pain + aching Progressive flat foot deformity Forefoot problems: progressive hallux valgus, metatarsalgia, lesser toe deformities Rarely, tarsal tunnel syndrome Valgus hindfoot Aquired flatfoot Forefoot abduction
Describe the treatment of tibialis posterior insufficiency
Non-surgical
- Analgesics - Shoe wear modification - Orthotics- medial arch supports - Physiotherapy
Surgery
- Reconstruction (tendon transfer) - Fusion (if secondary arthritis)
Describe the surgical approach to posterior tibialis anterior
Position: Supine
Landmark: Tip of medial malleoli and the base of the navicular
Incision : 10 cm longitudinal incision from tip of MM
Internervous plane : None
Dissection : Avid damage to the long saphenous vein and nerve
Divide the retinaculum and identify the tibialis posterior tendon by pulling on it
( FHL will plantart flex the great toe and FDL will plantarflex the lesser toes)
Dangers: Saphenous nerve and the tibialis posterior tendon are particularly vulnerable
Describe the presentation of ankle arthritis
Usually post-traumatic Presentation: Pain Swelling Deformity
Describe the pathology of ankle arthritis
Nasty fracture – cartilage damage Malalignment – leads to abnormal loading Biomechanics altered in the ankle joint Leads to abnormal point loading Eventual joint space narrowing and pain
Describe the surgical management of ankle arthritis
Failed medical / non-operative control…………
“Early” disease - joint preservation
Arthroscopy (or open procedure)
Debridement / synovectomy
“Late” disease – joint abolition or replacement
Arthrodesis (fusion)
Arthroplasty (replacement)
Excision Arthroplasty (excision joint)
Describe ankle arthroplasty
Indications
Pain relief
Preservation of joint mobility
Preservation of function
Polyarthropathy; Subtalar / Triple complex
List the indications for ankle fusion/arthrodesis
Pain relief
Severe deformity
Describe Anterior Approach to the Ankle for TAR
Position : Supine
Landmarks: Both the malleoli which are subcutaneous
Incision : 15 cm longitudinal incision midway between the malleoli
Internervous Plane: None
Intermuscular plane : Between EHL and EDL ( both supplied by deep peroneal but receive their supply proximal to the incision)
Dissection : Find the neurovascular bundle and mobilise laterally
Dangers: i. Superficial peroneal nerve ii. Deep peroneal nerve iii. Anterior tibial artery iv.
Describe Tibiotalocalcaneal Arthrodesis(TTC)
Severe deformity
Osteoporotic ankle fractures
Complex failed ankle fixation
Failed TAR
Describe ankle sprains
Lateral ligament
Passes form anterior margin of the fibular malleolus, to the talus bone
List the 3 elements of the lateral ligament
Anterior talofibular ATFL
Calcaneofibular CFL
Posterior talofibular PTFL
Describe ATFL/CFL
Weakest and commonly injured Commonly gets bruised and stretched during inversion injuries Prevents talar tilt If weak then the ankle feels unstable Positive anterior drawer test Positive talar tilt test
Describe the treatment of ankle sprains
Majority sprains recover within 3 months
Beware the sprain that persists…..
Back to basics – clinical reassessment
Describe Acute lateral ligament sprain (ATFL)
RICE Physiotherapy directed rehabilitation Loading injured ligaments Proprioception Strength and return to function
How is chronic instability diagnosed?
Examination: Positive anterior draw
Further investigations
Stress radiographs
MRI (very useful to demonstrate related pathology)
Describe hallux valgus
Commonly incidental finding
Female»_space;> Male
Family history +/- footwear
No symptoms = No surgery
List the symptoms of hallux valgus
Pain Deformity Modification of shoe wear Nerve irritation Lesser toe deformity
Describe the treatment of hallux valgus
Non- Surgical Surgical Bunionectomy Osteotomy Proximal Metatarsal shaft Distal Ist TMT joint fusion Technique used depends on the cause and the amount of correction required
Describe the dorsomedial approach to the great toe
Position: Supine
Landmarks: easily palpable 1st MTP joint
Incision: Proximal to the IP joint and curve over the medial eminence staying medial to EHL
Internervous Plane : none
Dissection: divide fascia and then periosteum
Dangers: i. Dorsal cutanous nerve ii. Extensor hallucis tendon iii, Flexor hallucis longus
