Labral tears and altered motion during loading.

"One might argue, that we sit the majority of our days with our femur and thus our femoral head pressed forward into the anterior and roof of the acetabulum. This becomes particularly suspect when in a conforming chair, such as a "bucket" seat in a car." -Shawn Allen

This article follows nicely with yesterday's post about hip joint control and anterior hip pain.

The premise behind this study referenced below was to determine if contact forces and electromyography (EMG) muscle amplitudes were altered during lunging activities in clients with painful labral tears compared to hose who are symptom free.
The unsurprising conclusions of this study ("contact forces and EMG muscle amplitudes are altered during the lunge for patients with symptomatic labral tears") are mostly predictable. But one should, we would hope, propose the chicken or the egg theory here.  Are these clients having pain because they are loading into the labral tear, or is the pain from poor joint stabilitation (and thus possible impaired normal mobility and motion) which incidentally lead to the labral loading and thus tear ?  We propose this one all the time. Why? Because we get a decent population of clients with typical "suspect" anterior hip labral pain and after rehabbing them, the pain resolves. So in these cases, was it a labral tear? Labral irritation? Or just a faulty loading response?
*However, we also get enough clients who present with an MRI in hand that confirms a labral tear, and we take them through the same process, and many of them also stabilize and have pain resolved. This then proposes the end question from them "So, was my pain from the labral tear at all? Or was it because had a poor stabilization capability, which lead to the tear/irritation?" 
And that folks, is the big question that has to be asked in all cases, and that is the unanswerable question.  But, should the process change regardless? If your client is going to head into surgery for the tear, should they not be fully rehabbed in the first place? And if the rehab works, is surgery even necessary ?  In the successful cases, we just stare openly at the client and smile, we let them answer the question. After all, they know the answer anyways.

Make no mistake. not everyone responds to our, or your, care. And, not every labral tear is incidental. Not every labral tear is undamaging to the femoral head and to the longer term health of the joint.  But, taking a few weeks and dedicating some good work into your client's skill, endurance, strength, power and loading responses often either give your client answers or prepare them for a great outcome post-operatively. 

In a nut shell, these can be tricky challenging cases. People sit and use the glutes as a cushion all day. We sit the majority of our days with our femur and thus our femoral head pressed forward into the anterior and roof of the acetabulum (depending on our sitting posture and chair choice).  They load similarly in their cars in challenged ways. They do not move well or often enough. They have weak glutes and abdominals and their ability to control the pelvis in safe loading is poor.  So many patients, and non-patients are on this bus, in fact, the majority of us are on it as well.  It feels like we are seeing more and more of these anterior hip problems, and we are not surprised as the average human moves less, is getting weaker and less durable and robust physically, and they sit more, and drive more.  This anterior hip pain clinical entity should really be no surprise to anyone anymore.
To be thorough, this study did "surface electromyography electrodes were placed over the gluteus medius, gluteus maximus, adductor longus, and rectus femoris muscles of the patients' involved limb and matched limb of asymptomatic controls."  This makes this an incomplete study with incomplete conclusions. As we said yesterday, without information on the mighty psoas and iliacus to name a few other big players, this study is somewhat suspect, but overall, we do not thing the results would come out too terribly different.

-Shawn and Ivo, the gait guys

Do Neuromuscular Alterations Exist for Patients With Acetabular Labral Tears During Function?
Arthroscopy. 2016 Jun;32(6):1045-52. doi: 10.1016/j.arthro.2016.03.016. Epub 2016 Apr 27.  Dwyer MK1, Lewis CL2, Hanmer AW3, McCarthy JC4.

https://www.ncbi.nlm.nih.gov/pubmed/27129378

More anterior hip pain dialogue.

On a recent podcast we discussed complex hip problems, particularly hip stability and mobility issues lending themselves to anterior hip pain.
We have often mentioned ankle rocker being important in the discovery of hip pain, insufficient rocker can cause some impairments and abilities to get to ample hip extension function and range.
Here, this slightly older article mirrors a discussion we had on a recent podcast. We discussed the need for balance in the hip. More so, that focusing only on the glutes and hip extension can get one into trouble. One needs to also consider hip flexion skill, endurance and strength. The glutes and the hip flexors are a team to help maintain hip stability, mobility, and centration of the opposing joint surfaces during roll and glide motions. This is some of Shirley Sahrman's work, and others of course. When these component parts are not in harmony, and a loading force potentiates the femoral head towards the anterior labrum, it is the job of the glutes and hip flexors, to name two of the big players, to centrate that femoral head and keep it from impinging, and applying a forward load especially when this occurs during end motion loading into hip flexion and extension. I came across an article a while back that suggested these anterior directed movement risks are greater when the limb is loaded from being externally rotated, such as when making a strong power move or "cut" off the stance leg into the contralateral direction (we are looking for that source).
The bottom line is pretty simple, create sufficient stability to endure the loading challenge, but have enough strength and skill to still enable safe mobility. That being said, it is the diagnostics and the remedy that can be the tricky and challenging part of this game.

Anterior hip joint force increases with hip extension, decreased gluteal force, or decreased iliopsoas force. Lewis CL1, Sahrmann SA, Moran DW. J Biomech. 2007;40(16):3725-31. Epub 2007 Aug 17.

"Abnormal or excessive force on the anterior hip joint may cause anterior hip pain, subtle hip instability and a tear of the acetabular labrum.

We found that decreased force contribution from the gluteal muscles during hip extension and the iliopsoas muscle during hip flexion resulted in an increase in the anterior hip joint force. The anterior hip joint force was greater when the hip was in extension than when the hip was in flexion."