What is a Lisfranc fracture?
The midfoot gets no respect. While people can relate to a stubbed toe or
sprained ankle; the part of the foot that connects the two, and is responsible
for helping absorb the shock of walking, running, and jumping isn't given much
thought. Not so for the French surgeon Jacques Lisfranc de St. Martin, a surgeon
in Napolean's army. Dr. Lisfranc studied the midfoot bones, the joints where
they connected, and the ligaments that held them together. Understanding that
anatomy led to his name being attached to the classic Lisfranc fracture
dislocations that occurred when horsemen fell and their foot was trapped in the
Most people, including doctors (except for orthopedic and podiatric surgeons)
quickly forget or vaguely remember about the row of bones between the ankle and
the metatarsal bones (the long thin bones that lead from the toes to the middle
of the foot). But the relationship of the cuneiforms and the cuboid bones allow the
foot to disperse the energy and shock that is generated by the weight of the
body. A Lisfranc injury disrupts those joints that hold the midfoot stable.
Causes of Lisfranc fractures
While history said that the injury was equestrian in origin, the most common
cause of a Lisfranc fracture is stepping into a hole and falling forward. The
toes of the foot are trapped and pointed downward, and in car accidents the foot
is trapped and rotates. This is also the same mechanism that can occur in
football, where a pointed toe gets caught and an opponent falls onto the back of
the heel, most often damaging the Lisfranc joint.
History names parts of the body based upon discovery, and the Lisfranc
describes the connection of the second metatarsal (that attached to the 2nd toe)
to the medial cuneiform (one of the midfoot bones that can be palpated or felt
on the top of the foot). When injured, this area can swell and be very painful.
Walking is difficult, and patients often mistake this for an ankle sprain. If
there is just a sprain, the physical examination can reveal only minimal
swelling and the findings can be subtle. However, if there are broken bones and
the joints dislocated, the appearance of the foot can be quite dramatic with
significant swelling and pain.
X-rays can be deceiving. Sometimes the injury is obvious, but the X-rays can appear normal. It is up to the doctor to have a high index of suspicion to look
for the ligament damage, and subtle alignment changes of the joint. If that
suspicion is high, the doctor may order a
CT scan to look for an occult or hidden
fracture. The doctor's intuition is important in this injury because up to
50% can be missed on plain X-ray films.
Lisfranc fracture treatment
If a Lisfranc injury is present, the treatment depends upon the bony
alignment. If the bones are where they are supposed to be, treatment in a
non-walking cast for 6 weeks may be enough. It's important to remember that
close follow-up is needed in case the bones shift in position. If the initial
alignment is poor, surgery may be needed to place a screw across the injury
to keep the bones in place. Unfortunately, after the injury heals, good looking
X-rays may not provide good looking results. Up to 25% of patients with a Lisfranc
fracture that is well treated may go on to develop
arthritis in the joint and
intractable pain requiring fusion of the joints.
Lisfranc learned in the 19th century what we know now to be true. Sprains are
significant injuries where ligaments tear and joint surfaces shift, and this
type of injury should
not be ignored. The lesson also learned is that history and physical examination
are perhaps more important than tests and X-rays. Touching the patient and
understanding the mechanism of injury are cornerstones of diagnosis.
Emotional trauma is best described as a psychological response to a deeply distressing or life-threatening experience.