Sunday wasn’t Matt Shaub’s day. (J. Meric / Getty Images)

Little understood, infrequently mentioned, it occasionally raises its ugly little head and creates havoc — as it did Monday when it was determined that that is what ails Houston Texans quarterback Matt Schaub. The Texans, 7-3 and looking so good, now face the prospect of using Matt Leinart as their starter — possibly the rest of the way. Reports from ESPN and CBS Sports indicate that Schaub will miss the rest of the season.

Just what is a Lisfranc injury?

First, Lisfranc. He was, as you might have guessed by his name, a French surgeon who first described the mid-foot injury in the 1800s. In those days, it often occurred when a man fell from a horse and caught his foot in the stirrup. Today, it more commonly occurs when the foot is pointed and someone or something lands on the heel or when someone steps in a hole and twists the foot. Lisfranc injuries can include any combination of sprains, dislocations and fractures.

According to the American Academy of Orthopaedic Surgeons website:

Lisfranc injuries occur at the midfoot, where a cluster of small bones forms an arch on top of the foot between the ankle and the toes. From this cluster, five long bones (metatarsals) extend to the toes. The second metatarsal also extends down into the row of small bones and acts as a stabilizing force. The bones are held in place by connective tissues (ligaments) that stretch both across and down the foot. However, there is no connective tissue holding the first metatarsal to the second metatarsal. A twisting fall can break or shift (dislocate) these bones out of place.

Schaub, according to the Houston Chronicle, could be lost for the season if he must have surgery for the injury he suffered Sunday on a quarterback sneak in the second quarter of Houston’s 37-9 victory over Tampa Bay. “Somebody fell on the back of his foot, and his foot got caught in the pile,” Coach Gary Kubiak said. “He played the rest of the game. He was sore. We asked him and he said, ‘I’m fine.’

“They taped it up at halftime, and he played. He was complaining about it in the fourth quarter, and we took him out of the game.”

Schaub, who hasn’t missed a start since 2008, had an MRI Monday morning. “After the game, the doctors still felt like he was going to be fine, so this all took place today,” Kubiak said.

That’s not surprising. The AAOS site says the injury can be tricky to diagnose.

Lisfranc fracture-dislocations are often mistaken for sprains. The top of the foot may be swollen and painful. There may be some bruising. If the injury is severe, you may not be able to put any weight on the foot. Lisfranc injuries are often difficult to see on X-rays. Unrecognized Lisfranc injuries can have serious complications such as joint degeneration and compartment syndrome, a build-up of pressure within muscles that can damage nerve cells and blood vessels. If the standard treatment for a sprain (rest, ice and elevation) doesn't reduce the pain and swelling within a day or two, ask your doctor for a referral to an orthopaedic specialist.

Texans guard Mike Brisiel and safety Dominique Barber have had Lisfranc injuries and underwent surgery. Brisiel returned; Barber is on the injured-reserve list. Shaub will visit several foot specialists before a decision is made on whether he’ll have surgery.