Friday, September 13, 2013

Science Friday: Diagnoses and Discoveries About Hips

Note: This is not a typical Science Friday, but Part 2 in the unexpected series identifying what is wrong with RunnerTeal.  (Let’s hope for no Part 3 anytime soon.) 

Last week I told you about my not-so-hip hip and my upcoming doctor’s appointment.  Everyone’s well wishes and thoughts paid off, as I do not have a surgery-requiring labral tear, but tendonitis in my hip flexor instead. (Yippee!!) Tendonitis means no running for a few more weeks, being forced to confront my hatred for biking, and no fall marathon. (The Philadelphia Marathon has now stolen my money for the last two years. I’ll get you back some day, Philly…) But, it isn’t surgery, and that is a huge relief that indisputably makes a few run-less weeks and hours of boring biking seem like a blessing.

Given the crash course I’ve had the last few weeks, I thought it might be nice to share some of the things I’ve learned about hips, both their tears and tendons.*

The hip is a ball and socket joint, like the shoulder, where the head of the femur (the ball) sits in the pocket (called the acetabulum, the socket) of the pelvic bone. This allows for motion in almost all directions and allows us to walk, jump, and of course, run. It absorbs a lot of forces; when we run, the forces are many times our body weight. The hip is the superstar of joints.

The acetabular labrum is the cartilage that surrounds the socket, helping to keep the femur securely in place. Running repeatedly over years and years (as marathoners are wont to do) can cause the labrum to wear thin and tear. (This can also occur more instantaneously in contact sports or accidents.) The pain occurs on the inside of the hip and it may present as stiffness and tightness or it may feel like it’s clicking or catching. The latter is the symptom that had me (and Dr. #1) convinced I had a tear. If the tear is bad enough, arthroscopic surgery may be required, where the torn portion is cut out. After seeing my x-ray and hearing my description—when the pain was worst, what time of day it hurt, etc.—my doctor was less than convinced that I had a labral tear, and did an ultrasound to check. If I had a tear big enough to need surgery, he’d see it on the ultrasound. Fortunately, he found a healthy looking labrum! He diagnosed me with tendonitis of the hip flexor instead.

The hip flexors are a collection of muscles that mainly function to pull the leg and knee upward, towards the body. Two of these muscles, the iliacus and the psoas major (together referred to as the iliopsoas), are the most susceptible to hip flexor injuries, and tendonitis can occur in the tendons associated with these muscles. (Tendons attach muscles to bones.) When under repeated stress, tendons can degenerate and become inflamed. (The suffix “-itis” means inflammation.) The stress could come from doing too much too soon or from overuse, pushing too hard for too long—again as marathoners are wont to do. If the tendons are inflamed or aggravated, most likely the surrounding muscles are as well. During my appointment, the tightness and stress on these muscles was obvious. The psoas major connects the lumbar part of the spine (the lower back) to the front of the pelvis. When my doctor pressed on my lower back, I could feel pain in the front of my hip—a strange sensation that convinced me he knew what he was talking about. (An interesting side note: only about 50% of people have a psoas minor. It seems not to matter whether you do or do not have this weak muscle.)

Treatment for tendonitis includes anti-inflammatories, physical therapy, massage, and, of course, the most hated treatment: a break from running. The tendon is able to heal itself; the purpose of the initial inflammatory process is to promote healing. As with all injuries, the trick is patience: let your body work its magic (and have a really good PT to help coax it along.)

Here’s a quick run down of other hip issues that affect runners:

Bursae are lubricating sacs that cushion areas where muscles and tendons slide against bone; bursitis is an inflammation of these sacs. Trochanteric bursitis will cause a dull ache or rubbing on the outside of the hip. Again, the treatment includes rest and ice/anti-inflammatories.

Stress fracture:
In the hip region, the most common place for a stress fracture is the neck of the femur. A stress fracture causes a throbbing pain that gets worse with more running and will probably leave you limping. If you can’t hop on the affected leg, a stress fracture is probably the issue, and you should immediately stop hopping and stop running. Here the treatment is 6-8 weeks of no running.

Iliotibial (IT) band syndrome:
This can present as a jabbing pain on the outside of the knee, but it starts up in the hips. IT band syndrome is from irritation of the ligament that runs along the outside of the thigh from the hip to the shin. You can get it from doing too much too soon (always trouble!) or even from running the same direction on the track (too many left turns!) IT band syndrome can be helped with rest, ice/anti-inflammatories, and massage before starting a program that strengthens the surrounding muscles.

Piriformis syndrome:
This is literally a pain in the butt, as pain shoots from the butt down the back of the leg. It can be treated with massage and physical therapy.

Staring at images of skeletons, muscles, and joints and learning all the things that can go wrong makes me appreciate how amazing it is that, most of the time, things work smoothly to allow us to move around. And, someday soon, to run again.

*Note: I am not a doctor, just a scientist who likes to teach herself things. You should see an actual doctor if you’re having hip trouble.

Dream big, 


  1. Thank you for the detailed report. I like especially the final paragraph (above the Note). There's a big truth there... about hips and all the rest of our bodies!

    Heal quickly -- but take time to make sure you are all better!

  2. It's a shame that the hips are so often overlooked when it comes to exercise. I believe that's why they tend to creep up on people and cause them problems - it's easy to forget that they're even there.

    Sarah | Mass Gain Source