Next speaker is going to be Ken Maroczek. He's from NYU and the Chief of Joint Diseases, Foot and Ankle Division, and we're happy to have him talk about perineal tendon pathology. Thanks a lot for coming. Thanks for having me, Matt. So, nothing to disclose. The anatomy of the perineal tendon is important to know about the perineal groove and the posterior fibula. It's a fiber cartilaginous rim which helps hold the tendon in place along with the superior perineal retinaculum, or the SPR. So, within the groove, the peroneus brevis is anterior and medial to the peroneus longus. The function of the peroneal tendon is primarily hind foot eversion. Secondarily, it also plantarflexes the ankle. Remember, the peroneus longus goes in the midfoot and also plantarflexes the first right. The tendons themselves have a watershed zone at the posterior to the tip of the fibula, and this is where a lot of times they tear, particularly the brevis. Anatomic variations associated with both tearing and subluxing are low-lying peroneus brevis, a muscle, as well as a peroneus cortis muscle is overcrowding the groove. So, what can the tendons do? They can be inflamed with tendonitis. They can tear, and they can sublux or dislocate. So, we'll talk about tendonitis first. Both tendons usually have overuse, complaint of pain, swelling over the peroneal tendons. You can feel that on examination. There's localized tenderness. Reproduce pain with resisted heel and eversion. And, you know, look for a varus heel, which may cause more stress in the tendons. Treatment, like most things in orthopedics, is non-operative initially with resting, activity modifications, anti-inflammatories. Immobilizing in some type of boot or stirrup. Basically, I tell them to stay in a pain-free zone. So, if not running makes them pain-free, then I tell them to do that. If they can barely walk, then I put them in a cam boot. Physical therapy, once things quiet down, you know, try to mobilize them first and wake them back up with therapy. And if they have a varus heel, you should put a lateral heel wedge in there. I get an MRI when they fail to respond. I usually don't send people an MRI initially, but a lot of times they come in with MRIs initially. But I get an MRI, basically, when they fail to respond. And usually you see fluid in the tendon sheath. You're looking for a relative perineal tendon tear. Before I do a tenosynovectomy, a lot of times I'll send them to a rheumatologist. Because if they're following, if they really only have tendonitis and they're following the treatment protocol, they should get better. It's very rare to do a tenosynovectomy. So I'll send them to a rheumatologist first to check before I do surgery. With tendon tears, usually the symptoms and exam are similar to tendonitis. It may show some weakness. Obviously a complete rupture would show weakness, but most of the time these are partial. This can be associated with chronic lateral ankle instability and also OCDs. Similarly, it's initially conservative. You'll mobilize them, much like tendonitis treatments. So like we talked about before, failure of a patient to get better, where you get an MRI to confirm the tear, and a lot of other pathology. So the peroneus brevis normally tears at the tip of the fibula. The peroneus longus sometimes tears a little more distally at the peroneal tubercle. You can have both split tears of the brevis and the longus. Like I said, they're usually split or partial tears, longitudinal, not transverse, and usually they're chronic. A complete rupture can occur with both the peroneus brevis or longus. Sometimes people have prodromal symptoms where they've been aching for a while and then they hear a pop. Peroneus longus, it can be difficult to repair, but sometimes it tears right at the cuboid tunnel and it can retract into the midfoot, so that can be very difficult to reconstruct. So the etiology of peroneal tendon tears. Usually there's something compressing in the groove, a low-lying peroneus brevis muscle or peroneus cortis. Sometimes it's subluxation and dislocation. They're popping over the distal fibula. It can tear. It usually occurs in the watershed region. And ankle instability. People keep spraying their ankles and they have lax ligaments. The tendons have to work overtime so they can be stressed out. Surgical treatment. Obviously you repair the tendon directly. If the severe tear or degeneration is greater than 50%, you can consider weaving the brevis and longus together and creating one tendon. If it's very little tendon left, you can consider doing the FDL transfer if both are gone. And if they have a varus, he'll consider doing a lateralizing calcaneosteotomy to bring them into neutral. So peroneal tendon dislocation and subluxation was originally described in skiing. And it's funny how oftentimes that actually happens. So, you know, if you have a person who's skiing and they have ankle pain, really ask them and have a little higher suspicion because it can be missed. There's nothing else that can really happen to the ankle and foot in the ski boot except tendons can dislocate or sublux. Dislocation or sublocation can be associated with a shallow peroneal groove, like you mentioned about overcrowding with a cortis or a low-lying brevis muscle. So the mechanism of injury is usually inversion and a dorsiflexed ankle contraction at peroneal. So if you just think about your foot in a ski boot, if you're trying to, you know, your brevis and longus fire and it pops out of place. Almost every patient describes a popping or snapping sensation, and they can reproduce it a lot of times. So if they come to you with this problem, it can be obvious when it pops and snaps. You want to check stability. You want to evert from a dorsiflexed position. Do circumduction both directions, clockwise and counterclockwise. And always compare it to the contralateral side because a lot of people have high-riding tendons. They kind of come up, but they don't pop out of place. Always check the other side. MRI to look at the SPR. They may have a small bony or fleck or avulsion, and also to rule out a peroneal tendon tear. Immobilization has a high chance of failure. You know, I'll put them in a brace, but in reality I tell them they probably need surgery because it's most likely going to keep popping out of place. There are many different described procedures in the literature and history for peroneal tendon dislocation, but what's really kind of come to be accepted is a deepening of the groove with repair or imbrication of the SPR, and I'll show you that right now. This is a case with a patient who had a split tear of the brevis and also a dislocating tendon. So if you see here, just to give a point to here. If you see, this is distal. That's proximal. And you can see that that's anterior and posterior. This is shiny. This shouldn't be shiny right here. You see right over here? This is just avulsed over here. You can see a little tip also. So this is the tendons here, but it's just shiny and it's completely avulsed. And I cut this sheath initially to get in there. And this is a small split tear of the brevis. This is a lot of times how it looks. It's on the undersurface. Always turn the tendon over and look underneath. You can miss it otherwise. And it's not as dramatic as you think sometimes. Some are shredded, but this is one that was torn because it kept dislocating. And I just did a repair, just a baseball-stitch repair. And you can see once again how shiny the fibula is because it was avulsed off the SPR. So we do a sort of coffin type. You bring the ledge of a cancellous ridge, bringing it down, lifting it up, and then you shave back about five millimeters or more of cancellous bone. You try to keep the ridge smooth and in one piece. I don't know how other people feel, but I never put a plate posteriorly. I know the trauma guys do because it's supposed to be stronger, but I think it's ridiculous. When you see this right here, this is smooth, and the tendons go right here and it tears up the tendons. So I try never to instrument a plate back posteriorly. So you pack it back in place, and it's pretty stable. You can see how much deeper it is now. And I put drill holes through the tip of the fibula posteriorly, and we bring through the sutures. This is the SPR. Tie it down and then do a sort of pants over vest with the periosteum of the fibula on top of it. And it's very stable. And that's it.

perineal tendon pathology

anatomy of perineal tendon

tendonitis

tendon tears

surgical treatment