PAINFULOSTRIGONUM
- The os trigonum is an ossicle present in 7 to 11% of
the population as a continuation of the posterior talar
process. - The painful os trigonum syndrome is one cause of
posteromedial ankle pain. This syndrome is most
prevalent in athletes who perform frequent or forceful
plantar flexion. The condition may be misdiagnosed
as other conditions such as Achilles’ tendonitis
(Martin, 2000). - Presentation is with pain in the posterior medial ankle.
There may be tenderness to palpation over the os or
pain with dorsiflexion/plantarflexion, or movement of
the great toe. The lateral X-ray may reveal the pres-
ence of the os trigonum. - Initial treatment is conservative with nonsteroidals
and activity modification. Surgical excision may be
required with failure of nonoperative management
(Blake, Lallas, and Ferguson, 1989).
TARSALCOALITION
•Tarsal coalition is fibrous (syndesmosis), cartilagi-
nous (synchondrosis), or osseous (synostosis) bridg-
ing of two or more tarsal bones.
- It often presents in older children or adolescents as
ankle instability and pain, or painful flat foot and
decreased subtalar motion. Pain localized to midtarsal
area, exacerbated by standing or athletic activity.
Bilaterality is common (as high as 50%). Incidence is
less than 1%. - The etiology is unclear. There may be a congenital
form that is autosomal dominant with variable pene-
trance. Failure of mesenchymal segmentation has been
proposed as cause (Pachuda, Lasday, and Jay, 1990). - In early childhood the union is fibrous and mobile and
is thought to become symptomatic as union becomes
cartilaginous or osseus. - Radiographic evaluation should include AP, lateral,
and oblique views of the foot. Coalition between the
talus and navicular can be seen on the lateral.
Coalition between the calcaneus and navicular, and
the cuboid and navicular can be seen on the oblique
films. Consider axial view of the calcaneus or CT if
routine views fail to show abnormality.
•Talonavicular coalition is frequently mild, may present
as early as 2–3 years old and respond to treatment
with a plastizote shoe insert. Calcaneonavicular
coalition commonly presents inpatients between
8–12 years of age. Surgical excision of the coalition
may be indicated in patients with a cartilaginous
bridge and no degenerative changes in the talonavicular
region.
•Talocalcaneal coalition frequently presents during
adolescence. It may occur in the anterior, middle, or
posterior facet. Treatment with immobilization in a
short leg cast may relieve symptoms. Surgical treat-
ment may consist of resection of the coalition or triple
arthrodesis (Pachuda, Lasday, and Jay, 1990; Kulik,
Jr, and Clanton, 1996; Varner and Michelson, 2000).TARSOMETATARSALFRACTURE-DISLOCATIONS
(LISFRANCINJURIES)- Injuries to the tarsometarsal joint are called Lisfranc
injuriesafter a French surgeon in the Napoleonic era.
Injuries to the tarsometatarsal joint are typically asso-
ciated with high-energy trauma, but may also occur
with lower energy mechanisms in athletics. - The base of the metatarsals and adjacent tarsals are
wedge-shaped, forming a “roman arch” to support the
transverse arch of the foot. The second metatarsal base
dovetails with adjacent tarsals and metatarsals to form
highly stable articulation. The third through fourth
metatarsals are connected at their bases by transverse,
oblique, and interosseous ligaments. The second
metatarsal is connected to the medial cuneiform by the
strong Lisfranc ligament.
•Forced plantar flexion may injure the weaker dorsal
ligaments. Direct blows to the dorsum of the foot or
rotational injuries may also injure the tarsometatarsal
joint (Solan et al, 2001). - Lisfranc injuries may be purely ligamentous without
apparent fracture. Consequently they are often
missed. Swelling and tenderness in the midfoot with-
out obvious fracture should raise suspicion.
Significant soft tissue injury may be associated with
tarsometatarsal injuries and may be associated with
compartment syndrome. Instability of the tar-
sometatarsal joints can be determined by palpating the
joint while grasping the metatarsal heads and apply-
ing a dorsally-directed force, although this may not be
tolerated in the acute setting.
•While markedly displaced fracture-dislocations are
obvious, some dislocations may spontaneously reduce
and non-weightbearing radiographs may appear
benign. Three radiographic findings suggest subtle
tarsometatarsal injury. The first is disruption of conti-
nuity of a line drawn from the medial base of the
second metatarsal to the medial side of the middle
cuneiform on the AP and oblique views. The second is
widening between the first and second rays. Third, the
medial side of the base of the fourth metatarsal should
line up with medial side of the cuboid on the oblique
view. Weightbearing radiographs, if tolerated, provide
excellent stress views. - Successful outcome is predicated upon anatomic
reduction. Injuries to the Lisfranc joint are treated by
open or closed reduction and stabilization with
screws or percutaneous wires, followed by a period
384 SECTION 4 • MUSCULOSKELETAL PROBLEMS IN THE ATHLETE