Hip injuries and pain are relatively common in runners; high hamstring strains, hip flexor strains, labral tears, piriformis syndrome, FAI... the list goes on. Most hip injuries are musculoskeletal (either bone/joint, ligament, or muscle), which can cause us to unintentionally neglect a particular group of hip injuries: nerve entrapments.
Nerve entrapments can occur in conjunction with other injuries. In fact, this is probably the most likely scenario as there is often something that sets up the right conditions for a nerve entrapment.
So what is a nerve entrapment? Sounds scary, but all it means is that a nerve is getting pinched or restricted in an area of your body. Depending on the nerve, this can cause pain, weakness, numbness, and/or tingling. Here, I will outline the symptoms of a few more common nerve entrapments, as presented by The International Journal of Sports Physical Therapy.
These hip impingements will be divided into two groups: anterior (front of the hip/leg) and posterior (back of the hip/leg). The two most commonly entrapped posterior nerves are the sciatic and pudendal nerves. A sciatic nerve entrapment can cause pain the butt that often gets worse with long periods of sitting (like at your desk... all day). Some types of sciatic nerve entrapment can cause pain with walking, especially just before you push off the ground because of the location of the nerve relative to your bones and contracting muscles, or pain with running (specifically pain behind the knee).
A pudendal nerve entrapment will cause pain just off the bony part of your butt that gets worse with sitting on a toilet seat, not on a regular chair. The hard, supportive surface of a normal chair will actually feel better given the location of the pudendal nerve. This nerve entrapment is common will long periods of cycling (again, a non- supportive sitting surface).
The three most common anterior nerves to become entrapped are the obturator, femoral, and lateral cutaneous nerves. An obturator nerve entrapment can cause inner thigh pain during exercise; a femoral nerve entrapment causes pain, numbness, and tingling in the front of the thigh; and a lateral femoral cutaneous nerve entrapment causes numbness, tingling, stinging, and/or burning at the front outer thigh. Lateral femoral cutaneous nerve entrapment is also called "meralgia paresthetica" and is more commonly found in gymnasts and scuba divers because of the direct trauma or pressure to this area in each sport. For gymnasts, the repeated trauma of hitting their legs on the uneven bars can cause meralgia paresthetica, and the pressure of a weight belt on scuba divers does the same.
As you can see, there are some pretty general symptoms associated with these nerve entrapments, so the diagnosis is often thought to be something else, or is missed when the condition isn't getting better. Nerve entrapments probably happen with another injury. The key here is if you're getting better addressing your ______ (fill in the blank-
hamstring strain, etc), but then hit an impassable plateau in recovery and healing, it might be time to start to address the nerve entrapment more directly. This would include manual treatments such as joint mobilizations and soft tissue work, as well as nerve mobility exercises, specific strengthening, and running form correction.
This is important information to put out there, as we all know that feeling of frustration when hitting a plateau in healing. Be on your guard! Pay attention to your recovery and own it.
Martin R Martin HD Kivlan BR. "Nerve entrapment in the hip region: current concepts review". The International Journal of Sports Physical Therapy. 2017; 12(7): 1163-1173.
Dr. Cathlin Fitzgerald, DPT, CSCS