Foot and ankle pain is common in children and adolescents. Problems are usually related to skeletal maturity and are fairly specific to the age of the child. Evaluation and management is challenging and requires a thorough history and physical exam, and understanding of the pediatric skeleton. This article will review common causes of foot and ankle pain in the pediatric population.
Foot and ankle problems are common in the pediatric population. Problems can be related to skeletal maturity and are fairly specific to the age of the child. An awareness of congenital anomalies, developmental variation, skeletal maturation and lower extremity alignment will aid the physician in evaluation and management. This article will review common causes of foot and ankle pain in the pediatric population. It is not meant to be an exhaustive review and will not review acute traumatic fractures.
Most foot and ankle pain in the active pediatric population are associated with minor trauma or repetitive stress combined with abnormal biomechanics of the foot and lower extremity. Older children may isolate pain to a specific site whereas toddlers are more likely limp or refuse to bear weight. Often there is no clear history of traumatic event. There are numerous, non-traumatic diseases that masquerade as injuries.
The clinical history should include a thorough description of the pain characteristics (location, character, onset, duration, change with activity or rest, aggravating and alleviating factors, night pain); trauma (acute macrotrauma, repetitive microtrauma, recent/remote); mechanical symptoms (locking, catching, clicking, instability, worse during or after activity); inflammatory symptoms (morning stiffness, swelling); neurological symptoms (weakness, altered sensation); gait (limp, altered weight bearing); effects of previous treatments and the current level of function of the child. Location of pain is the most important historical factor in aiding diagnosis.
A history of previous injury and/or surgery, neurological disorder, chronic inflammatory joint disease or bleeding diathesis is significant. Family history of orthopedic, neurologic or rheumatic disease is also important.
Anatomy and physical examination
The basic anatomy of the foot and ankle is shown in Figure Figure1. 1. Foot and ankle pain can be localized to the forefoot, midfoot, hindfoot or ankle. The forefoot includes the metatarsals, phalanges and sesamoids; the midfoot includes the tarsal bones, (navicular, cuboid and three cuneiforms); and the hindfoot includes the talus and calcaneus. The Lisfranc joint includes the five metatarsophalangeal (MTP) joints and separates the midfoot and forefoot and the talonavicular and calcaneocuboid articulation (Chopart joint) separates the midfoot from the hindfoot. The subtalar joint separates the talus and calcaneus. Movement at the Chopart joint includes supination and pronation. Movement occurs in triplanar patterns at the subtalar joint: supination (inversion, adduction, plantarflexion) and pronation (eversion, abduction, dorsiflexion) The main functions of the foot are to support the body, absorb shock from ground reaction forces, and to provide a rigid lever for gait.
Anatomy of the foot and ankle. (Picture courtesy of Allan McGavin Sports Medicine Centre patient handouts).
The ankle is a simple hinge joint composed of the tibia and fibula, which both articulate with the talus. Movement occurs in triplanar patterns: dorsiflexion and plantarflexion, dorsiflexion with eversion and abduction, and plantarflexion with inversion and adduction. Static stability is provided by the lateral ligament complex (anterior talofibular, calcaneofibular and posterior talofibular ligaments) and the medial deltoid ligament (originates from the distal tibia). Dynamic stability is provided by the peroneus brevis and longus muscles laterally (everts foot) and the posterior tibialis muscle medially (inverts foot). The main functions of the ankle are to provide stability for weight bearing and to allow mobility of the foot [1 ].
During the clinical assessment the physician should try and reproduce the patient's foot or ankle pain through palpation and manipulation. Biomechanical examination is important in determining any potential predisposing or contributing factors. This should include an assessment for genetic predisposing factors such as excessive stiffness, loose-jointedness, pes planus, pes cavus, and/or increased or decreased muscle tone. Functional biomechanics should be assessed by evaluation of gait, and maneuvers such as jumping, hopping (single and double-leg), cutting and
figure of 8's running. Most causes of foot and ankle pain are unilateral, allowing comparison to the unaffected side. The lumbar spine, ipsilateral hip and knee should always be examined.
Standing [Pelvis heights, lower limb alignment, hindfoot position (varus, valgus), subtalar position (inversion, eversion), forefoot position (adduction, abduction), foot arch (cavus, planus), toes (claw toes, overriding fifth toe, Morton's foot with first ray shorter than the second), swelling, redness.]
Supine or sitting [Lower limb lengths and alignment, hindfoot position, forefoot position, foot arch, alteration of callus formation due to altered weight bearing, corns, plantar warts, onchocryptosis.]
Surface anatomy is best appreciated with the patient sitting. The foot and lower leg are stabilized by holding the foot around the calcaneus. It is important to palpate specific structures. The point of maximal tenderness should be correlated with the underlying bone or soft tissue anatomy. Palpate both malleoli and their respective physes, which lie 1 inch (2.5 centimeters) from the tip of each malleoli. Palpate over the joints, tarsal bones, metatarsals, phalanges and along the course and attachments of ligaments and tendons. Ankle joint effusion and tenosynovitis may be palpable.
3. Range of motion
The resting position of the foot and ankle is slight ankle plantarflexion (10°), subtalar neutral.
Passive movements [Ankle dorsiflexion (10–20°; if patient is unable to dorsiflex ankle with knee extended but can dorsiflex with knee flexed the gastrocnemius is the cause of limited range whereas if range limitation is the same with knee extended and flexed soleus is involved), ankle plantarflexion (50°), subtalar eversion (15–20°), subtalar inversion (35–40°), forefoot adduction (20°), forefoot abduction (10°), first MTP flexion (45°), first MTP extension (70–90°), motion of lesser toes.] Range of motion decreases with age, especially at the subtalar joint with eversion (10°) and inversion (20°) in adulthood.
4. Special tests
1) Tests for rigid or flexible flat feet [Observe patient's medial longitudinal arch standing, standing on his/her toes, and sitting. Presence of an arch while on one's toes or sitting and absent with standing suggests flexible flat feet. Absence of an arch in all positions suggests rigid flat feet.]
2) Thigh foot angle [Measure of tibial torsion. Patient prone with knee flexed to 90° and foot in relaxed position; measure angle between the axis of the thigh and foot. The thigh foot angle rotates laterally with increasing age; the upper limit of normal is 30°. Negative values are common in infants. Negative and positive values beyond the normal range are referred to as medial (internal) tibial torsion and lateral (external) tibial torsion respectively.]
3) Forefoot adduction correction test [Patient supine or prone. The lateral border of the foot is usually straight. If forefoot adduction is correctable to neutral or beyond with abduction it is "correctable" and if "fixed" it likely requires orthopedic intervention and casting.]
4) Anterior drawer and talar tilt tests for lateral ankle sprains. [The anterior drawer tests the stability of the anterior talofibular ligament (ATFL) and the talar tilt the stability of the calcaneofibular (CFL) ligament. It is normal to have a small amount of movement but pain, a soft endpoint and marked difference from side to side all indicate injury to the ligament. For the anterior drawer the ankle is relaxed in a neutral or slightly plantar flexed position, the tibia and fibula are stabilized with one hand while the other hand attempts to pull the talus forward out of the ankle mortise. The talar tilt is performed by inverting the calcaneus with the ankle in neutral position.]
5. External rotation test for "high" ankle sprains (injuries to the anterior tibiofibular ligament) [Stabilize the lower leg in neutral with one hand and abduct the foot with the other hand. The test is positive if it produces pain.]
The ankle, subtalar, forefoot and MTP joints should be moved thru active range and then placed thru full passive range of motion. Muscles that span two joints are important for functional range of motion and should be tested independently (gastrocnemius muscles).