Lisfranc's Joint
Lisfranc's Dislocation
Hardcastle Classification System
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Jacques Lisfranc (1790-1847) was a French surgeon in Napoleon's army. He is best known today for describing the joint that bears his name. What is Lisfranc's joint?Lisfranc's joint is the joint where the midfoot attaches to the metatarsal bones (the long bones in the ball of the foot through which the toes attach to the foot). This is also known as the tarso-metatarsal joint. See the X-ray to the right to see Lisfranc's joint |
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What is a Lisfranc's dislocation?
A Lisfranc's dislocation is where one or several of the metatarsal bones become misaligned with the bones of the midfoot (the cuneiforms and the cuboid bones). Small chip fractures of the metatarsals are often associated with this condition, but the biggest problem is the dislocation itself, which can be very debilitating when left untreated.
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Lisfranc's dislocations are
sometimes obvious, but they can be very difficult to diagnose at times,
with radiographic (X-ray) changes often very subtle and difficult to
discern. For this reason, it is very important that these
conditions be assessed by an individual who specializes in the foot. |
Who gets Lisfranc dislocations?
There are two main groups:
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Those exposed to sudden trauma. The trauma causing this injury may be severe, but modest "freak" injuries may result in this condition more frequently than you might expect. The mechanism is usually plantarflexion (the foot is pointed downwards) with a sudden twisting of the foot.
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Those with poor sensation in their feet. The largest members in this category are diabetic and alcoholic neuropathy. Lack of sensation from these conditions may lead to a Charcot foot, Lisfranc dislocations and severe arthritis and deformity.
How are Lisfranc injuries classified?
Most podiatric physicians use a modified version of the.........
Hardcastle Classification System:
Type A:
Total incongruity (all the metatarsals are dislocated, and together move as a unit in one direction).
Type B1:
Partial incongruity involving the medial metatarsals (the metatarsals nearest the big toe are dislocated).
Type B2:
Partial incongruity involving the lateral metatarsals (the metatarsals nearest the little toe are dislocated). The example above is a B2 because the 1st metatarsal has not moved; the 2nd, 3rd, 4th, and 5th metatarsals (the lateral metatarsals) have moved together away from the first metatarsal.
Type C1:
Divergent incongruity involving some metatarsals (2 or more metatarsals are dislocated in different directions.
Type C2:
Divergent incongruity involving all the metatarsals (all the metatarsals are dislocated, moving in different directions.
How are Lisfranc injuries treated?
A non-weight-bearing cast may be attempted in some cases, but in the majority of cases surgery is performed. Surgery usually involves realigning the metatarsals and holding them in place with pins (K-wires), Screws or External Fixation, then casting the patient in a non-walking cast. (For more information about how to hold bones together, please visit our web page on fixation techniques.
How do Lisfranc injuries heal?
Often quite well, but Lisfranc injuries often lead
to long-term, chronic arthritis in the affected foot. Additional surgery
to fuse the bones is sometimes necessary. Early diagnosis and treatment
increases the odds greatly of successful long-term treatment.