Chapter 19 The Ankle and Lower Leg
Chapter 19
Extended Lecture Outline
· Anatomy of the Lower Leg and Ankle
o Bones
§ Tibia
· Tibia is the longest bone in the body with exception of the femur
· Principle weight bearing bone of the leg
· Anatomical weakness present in the lower third of the shaft
§ Fibula
· Joins the tibia with an arthrodial articulation at the upper end, just below the knee and as a syndesmotic joint at the lower end
· Main function is to provide for attachment of muscles
§ Tibial and fibular malleoli
· Lateral malleolus extends further distally which creates stability on the lateral aspect of the ankle
§ Talus
· Second largest tarsal, and main weight-bearing bone of the articulation, rests on the calcaneous and receives the articulating surfaces of the lateral and medial malleoli
§ Calcaneous
· Forms the heel, attachment site for ligaments and the achilles tendon
o Articulations
§ Superior and Inferior Tibiofibular Joints
· The superior tibiofibular joint is diarthrotic – allows for some gliding movements
· Superior tibiofibular joint formed by the tibia’s lateral condyle and the head of the fibula
· Inferior tibiofibular joint is a fibrous articulation between the lateral malleolus and the distal end of the tibia
§ Talocrural Joint
· The ankle joint is a hinge joint (ginglymus)
· The ankle mortise formed by the distal portion of the tibia, lateral malleolus and medial malleolus articulating with the trochlea of the talus
· Movements include plantarflexion and dorsiflexion
§ Subtalar Joint
· Discussed in Chapter 18
· Movements that occur include inversion, eversion, pronation and supination
o Stabilizing Ligaments
§ Tibiofibular Ligament
· Oblique arrangement aids in diffusing the forces on the lower leg
· Anterior and posterior tibiofibular ligaments, which hold the tibia and fibula together, form the distal portion of the interosseous membrane (syndesmotic ligaments)
§ Ankle Ligaments
· Lateral Ligaments
o Anterior Talofibular: restrains anterior displacement of talus
o Calcaneofibular: restrains inversion of calcaneous
o Posterior Talofibular: restrains posterior displacement of talus
· Medial Ligaments
o Deltoid (anterior tibiotalar, tibionavicular, tibiocalcaneal and posterior tibiotalar)
o Deltoid helps to maintain the inner longitudinal arch along with the plantar calcaneonavicular (spring) ligament
o Prevents abduction and eversion of the ankle and subtalar joint
o Prevents eversion, pronation and anterior displacement of the talus
o Joint Capsule
§ Encases the ankle joint, thick on the medial aspect and becomes thin at the back
o Ankle Musculature
· Movements of talocrural joint = dorsiflexion and plantar flexion
· Inversion and eversion occur at the subtalar joint
· Tendons passing posterior to the malleoli produce ankle plantarflexion and toe flexion
· Tendons passing anterior to the talocrural joint dorsiflex the foot and produce toe extension
· Muscles that cross ankle joint laterally cause eversion and muscles that cross medially cause inversion
§ Muscle Compartments: divided into four distinct compartments bounded by heavy fascia – (See Table 19-2)
· Anterior Compartment: Contains the anterior tibial nerve and the tibial artery, also contains the muscles that dorsiflex the ankle and extend the toes (tibialis anterior, extensor hallucis longus, extensor digitorum, peroneus tertius)
· Lateral Compartment: Peroneus longus and brevis (evert ankle), superficial branch of the peroneal nerve
· Superficial Posterior Compartment: Plantaris, Gastrocnemius, and soleus (plantarflex ankle)
· Deep Posterior Compartment: Popliteus, Tibialis Posterior, flexor digitorum longus and flexor hallucis longus (invert ankle) Posterior tibial artery
o Nerve Supply
§ Lower leg supplied by the common peroneal nerve anteriorly. The common peroneal nerve branches into the superficial peroneal nerve and the deep peroneal nerve. Tibial nerve runs posteriorly and supplies the foot and ankle
o Blood Supply
§ Lower leg and ankle supplied by the anterior tibial artery and posterior tibial artery
§ Blood drains via the peroneal vein, posterior tibial vein and anterior tibial vein
· Functional Anatomy
§ The ankle is a stable hinge joint, with dome of talus articulating with distal ends of tibial and fibula
§ Medial or lateral displacement of talus prevented by malleoli
§ Talus is wider anteriorly than posteriorly – most stable position of the ankle is in dorsiflexion
§ Ankle ROM ranges from 10º Dorsiflexion to 50º of plantarflexion
§ Normal gait requires at least 20 degrees of plantarflexion and 10 degrees of dorsiflexion with the knee extended
· Preventing Injury to the Ankle and Lower Leg
o Achilles tendon stretching
o Strength Training
o Neuromuscular Control Training
§ Involves adapting to uneven surfaces by controlling motion at the ankle joint
§ Neuromuscular control can be improved by working/balancing on uneven surfaces daily (BAPS board, BOSU balance trainer, rocker board or dynadisc)
o Footwear (See Chapter 7)
§ Shoes should not be worn for activities for which they are not intended for (running shoes should not be worn for tennis)
§ Cleats should be placed far enough on the border to avoid ankle sprains
§ High tops offer more stability than low tops for those with previous ankle sprains
o Preventative Ankle Taping and Orthoses (See chapter 8)
§ Controversy over taping ankles that have no history of sprains
§ If tape constricts soft tissue may disrupt normal biomechanical function and create unnecessary injuries
§ Ankle braces superior to taping in preventing injuries
· Assessing the Ankle and Lower Leg
o History
o Observation
o Palpation (Bony and Soft-tissue)
o Special Tests
§ Lower Leg
· Lower leg alignment tests: Determine malalignment
· Percussion and compression Tests
· Thompson Test: Achilles tendon integrity
· Homan’s Sign: Indicates presence of deep vein thrombophlebitis
§ Ankle Stability Tests
· Anterior Drawer Test: Determines extent of injury to anterior talofibular ligament
· Talar Tilt Test: Determine extent of inversion or eversion injuries
· Kleiger’s Test: Determines injury to the deltoid ligament (pain over the deltoid ligament) and injury to the distal ankle syndesmosis (pain over the lateral malleolus)
· Medial Subtalar Glide Test: Determines presence of excessive medial translation of the calcaneous on the talus in the transverse plane (indicates injury to the lateral ligaments)
§ Functional Tests
· Walk on toes (tests PF)
· Walk on heels (tests DF)
· Walk on lateral borders of feet (tests inversion)
· Walk on medial borders of feet (tests eversion)
· Hop on injured ankle
· Recognition of Specific Injuries
o Ankle Injuries
§ Inversion Ankle Sprain (Grade I, Grade II, Grade III)
· Ottawa Ankle Rules: used to decide if radiographs are necessary (Do not apply to injuries that are more than 10 days old): Inability to bear weight for four steps at time of injury and evaluation, tenderness over the inferior or posterior pole of either malleolus including the distal 6 cm, inability to bear weight, tenderness along the base of the fifth metatarsal or navicular bone.
§ Eversion Ankle Sprain
§ Syndesmotic Sprain (High Ankle Sprain)
§ Ankle Fracture/Dislocation
§ Osteochondritis Dissecans
o Lower Leg Injuries
§ Achilles Tendon Strain
§ Achilles Tendinitis, tenosynovitis, tendinosis/tendinopathy
§ Achilles Tendon Rupture
§ Peroneal Tendon Subluxation/Dislocation
§ Anterior Tibialis Tendinitis
§ Posterior Tibialis Tendinitis
§ Peroneal Tendinitis
§ Shin Contusion
§ Muscle Contusions
§ Leg Cramps and Spasms
§ Gastrocnemius Strain
§ Acute Leg Fractures
§ Medial Tibial Stress Syndrome
§ Compartment Syndrome
§ Stress Fracture of Tibia or Fibula
· Rehabilitation Techniques for the Lower Leg and Ankle
o General Body Conditioning
§ Running in the deep end of pool, biking or upper body ergometer can be used to maintain CV conditioning while recovering from lower extremity injury
o Weight Bearing
§ During period of maximum protection immediately after injury – should be either non-weight bearing or partial weight bearing on crutches
§ Early ambulation, even if only touch down weight bearing is essential to prevent muscle atrophy, proprioceptive loss, circulatory stasis and tendinitis
o Joint Mobilizations
§ Mobilizations to restore DF (anterior tibial glides and posterior talar glides), and PF (posterior tibial glides and anterior talar glides) should be initiated early
§ Subtalar joint medial and lateral glides can be used to increase inversion and eversion
o Flexibility
§ Minimize inversion and eversion in early stages
§ Perform towel stretching for plantarflexors and standing or kneeling stretches for dorsiflexors to improve ROM
§ Start inversion/eversion exercises once tenderness has decreased (towel pulls side to side, drawing alphabet in capital letters while in ice bath)
o Neuromuscular Control
§ Early weight bearing decreases proprioceptive loss
§ Deficits in Proprioception can predispose an athlete to ankle injuries
§ Changes in joint position sense and kinesthesia found in subjects with chronically unstable ankles
§ Balance and coordination training can restore sense of joint positioning to normal
§ BAPS board, wedge board or Dynadisc in sitting to start progressing to standing
o Balance and Postural Stability
§ Postural control is significantly impaired with ankle sprains and may require 2-4 weeks to return to normal
§ Baps board, Bosu Balance Trainer, Rocker board, Tremor box, minitramp, dynadisc, start with UE support progressing to free standing
§ CKC exercises: leg presses, minisquats, single leg standing kicks
o Strengthening
§ Isometrics can be started early in the four major planes of motion
§ Isotonics for dorsiflexion and plantarflexion initiated first and as healing continues inversion/eversion can be added.
§ Pain should be basic guideline for starting inversion/eversion isotonic exercises
§ Light resistance with high reps has fewer detrimental effects on the ligaments
§ Resistive tubing exercises, PNF
o Taping and Bracing
§ Most desirable to have the athlete return to sport without the aid of ankle support, but some type of support may be needed initially
§ Taping does seem to have a stabilizing effect on unstable ankles without interfering with motor performance
§ Bracing may help the athlete detect movement in the ankle and thus may help reduce injury
o Functional Progressions
§ See Focus Box 19-1 “Return to running following ankle injury functional progression”
§ Should be full weight bearing when no limp is present
§ Running may begin as soon as ambulation is pain-free – Pain-free hopping on affected side may also be a guideline to determine when running is appropriate
§ Early running can also be started in the pool – starting in the deep end and progressing to the shallow end with increased weight bearing
o Return to Activity
§ Athlete should have complete range of motion and at least 80 – 90% of pre-injury strength before considering a return to sport
§ If tolerates full practice then can return to competition
§ Specific demands of each sport dictates the individual drills of functional sport progression
Prentice, Principles of Athletic Training , 15e LO-19 | 1