Breaking Down The Roope Hintz Injury

The pictures of where he was suffering this season might not be the faint of heart.

[Editor’s Note: I’m by no means a doctor, so when uncommon injuries come up when it comes to the Dallas Stars I turn to Erin Bolen, a previous Defending Big D editor and about-to-be doctor, to explain to me just how bad things are. She was kind enough to provide an analysis (complete with pictures!) to explain just what forward Roope Hintz played through this season.]

The great mystery has been solved. We know what was ailing Roope Hintz all season – an avulsed adductor muscle. But what the heck is that, and how do you fix it? What does it mean for his playing career? As a resident Defending Big D alumnus with some formal anatomical training at this point, I’m here to answer those questions.

Again, typical disclaimer – I am not quite a doctor, at least until this Friday when I graduate, and I don’t know anything about any player’s specific situation or medical decision making. This information is all general about anatomy, typical injuries, and typical repairs. If you think you’ve done this to yourself, first of all I’m sorry, and second make sure you are evaluated in person by a physician.

Let’s start off with the adductor muscles, who they are and what they do. A couple of basic medical terms – abduction is a motion that helps move something away from your body, like raising your elbows straight out to the side. Adduction is bringing something back toward the body, and because we’re super creative, we often name muscles that help with those motions after what they do.

Some of the biggest, strongest muscles in the body are around your thigh. Most people know about the glutes, quads and hamstrings for flexing and extending the knee and leg, but there are also large muscles involved in abduction and adduction. The adductors are a group of five muscles - adductor magnus, adductor longus, adductor brevis, pectineus and gracilis.

The largest and most powerful of these are the three muscles with adductor in their name, and they all start somewhere along the inner border of the femur, the big upper leg bone. They all insert on a tiny corner on the inside of the pelvis as shown below:

Importantly here, you can see there are some significant overlap in these insertion sites, so typically in medicine we just refer to the general area as the “adductor tendon” rather than sussing out which specific one we’re talking about.

Now onto this injury. You can injure a muscle in several ways, most commonly through strains (stretching and tearing of the muscle fibers themselves). Sometimes the fibers of the muscle can develop an inappropriate gap, which is what happens in a sports hernia/core muscle injury. There is inflammation of the tendon itself, called tendinitis, and tears at the level of the tendon, a tendon rupture. But what happens if the muscle and tendon are so relatively strong that they don’t actually tear, but the strain of the injury is still enough to cause huge tension? Sometimes an avulsion, where the edge of the bone comes off instead.

Avulsion fractures are most common when there’s a little dinky bone and a bigger, stronger muscle – a classic place for them is the outside of the foot in a bad inversion injury as a big muscle pulls on its attachment point, the corner of one of the long foot bones, and yanks the corner off. Avulsions can be complete or incomplete, where the whole tendon/bone complex is just kind of lying there for a complete avulsion versus a corner or portion coming off in an incomplete tear.

This all leads us back to Hintz, who had an incomplete avulsion of the left adductor tendon at the pelvis sometime early this season. Some sort of traumatic abduction (which would work against the tension of adductors) caused such a hard pull that a corner of the bone where the tendon was attached came off, but importantly to his ability to function, the rest of the tendon was still intact. He would have had significant pain and bruising around the time of the injury, and pain with adducting his leg against resistance as well as whenever anyone abducted his leg for him.

Another disclosure – I’m going into pediatrics, not orthopedics, so my baseline surgical repair knowledge is limited. But I did find this study from a couple years ago talking about this injury if you’d like to dive into the medical jargon. Essentially, it says this is rare injury seen primarily in male athletes, more common in soccer (the article says football, but it is a British journal). You can treat it with rest for small avulsions (i.e., let the ends of the bone hang out close to each other, in which time they will knit back together), which they define as a muscle retraction of less than 1 cm in the area of injury, or surgical pinning. Surgical recovery time until equal strength and pain-free motion averaged 12 weeks.

A morbid-but-true fact there is that bone injuries often heal better, more completely and often faster than similarly traumatic intramuscular or tendon injuries. Bone has great blood supply and good regenerative capability even after having been apart for a reasonable period of time, and it offers good structure into which you can anchor pins and screws and all sorts of helpful devices. Muscle doesn’t regenerate, and tendons have poor blood supply, and both are more like trying to sew thick fabric together as opposed to nailing blocks of wood. If you’re going to hurt something, we would often prefer it to be a bone rather than a muscle, tendon or ligament just for healing purposes.

Why did he play with this? Well, assuming the bone next to this avulsed area was completely intact on scans, it’s unlikely he could have made it worse without some sort of traumatic event that would have injured anything, already hurt or not. The biggest risk would have been some sort of compensatory strain/sprain/tendinitis type injury along his right side or potential left hamstrings/quads from favoring the area. I assume he was monitored quite closely for such things.

Hintz is scheduled to have surgical repair of the injury in New York, which almost certainly means at the Hospital for Special Surgery, on Wednesday, meaning the 12-week recovery until pain free/equal strength puts him at mid-August with time for on-ice rehab prior to training camp. HSS is a high-rent, big name, orthopedic-focused institute where both Jamie Benn and I’m willing to bet Tyler Seguin had their repairs done. Maybe even Alexander Radulov.

A quick note about Radulov and “sports hernias”/core muscle injuries. These live in the same area of the body and is usually from the abdominal muscles that attach just superior to that part of the pelvis.

These abdominal muscles get somehow weakened, sometimes through an intramuscular tear or other issue, and the resulting weakness while the area is also being yanked on by the giant adductors causes significant pain. Treatment can be conservative, with rest to allow healing followed by a trial of play, or surgical. A good article is found here, and if you prefer bullet form, this is your go-to.

Hintz and Radulov should make full recoveries and be ready to play by the time the season comes around. But both of them demonstrate quite nicely how annoying this region of the pelvis is (just ask any medical student learning pelvic anatomy) and how many ways it can make you mad.