The latest Inner Circle webinar recording on Assessing Shoulder Capsular Mobility is now available.
Assessing Shoulder Capsular Mobility
This month’s Inner Circle webinar is on Assessing Shoulder Capsular Mobility. This is a recording of an actual inservice we performed with the students and interns at Champion this week. I’m super excited to be able to record and share things like this with my Inner Circle. It’s like having a front row seat at our inservices! I think this offers many benefits over the traditional webinar/lecture format, as you can watch the interaction and also see some of the clinical techniques better.
In this webinar, we discuss:
The anatomy of the shoulder capsule and glenohumeral ligaments
How different arm positions stress different aspects of the capsule
How to determine which ligament and aspect of the capsule is tight
How to assess range of motion at different positions to assess different portions of the capsule
How to perform range of motion and capsular mobility assessment of the shoulder
I feel like we’ve been discussing anterior pelvic tilt lately in several articles and an Inner Circle webinar on my strategies for fixing anterior pelvic tilt. I wanted to show a video of a great example of how a simple assessment really tells you a lot about how pelvic positioning should influence how we coach exercises such as squats and deadlifts.
In this video, I have a great example of a client that has limited knee to chest mobility and with boney impingement. However, if we abduct the leg a bit, it clears the rim of the hip and has full mobility with no impingement.
As you can see, because he is in anterior pelvic tilt, he is prepositioned to start the motion in hip flexion, so therefor looks like he has limited mobility. I have a past article on how anterior pelvic tilt influence hip flexion mobility, which discusses this a little more.
While you are working on their anterior pelvic tilt, you can work around some of their limitations. I hate when people say there is only one way to squat or deadlift.
Our anatomy is so different for each individual.
Some need a wider stance while others need more narrow. Some need toes out while some need more neutral. Do what works best for your body, not what the text book says you are supposed to look like.
Today’s guest post comes from John Snyder, PT, DPT, CSCS. John, who is a physical therapist in Pittsburgh, has a blog that has been honored as the “Best Student Blog” by Therapydia the past two years. He’s a good writer and has many great thoughts on his website. John discusses some of our common beliefs in regard to the role of the proximal hip on knee pain. I’ll add some comments at the end as well, so be sure to read the whole article and my notes at the end. Thanks John!
Should We Stop Blaming the Glutes for Everything?
Anterior cruciate ligament (ACL) rupture1,2 and patellofemoral pain syndrome (PFPS)3,4,5 are two of the most common lower extremity complaints that physicians or physical therapists will encounter. In addition to the high incidence of these pathologies, with regards to ACL injury, very high ipsilateral re-injury and contralateral injury have also been reported6,7,8.
With the importance of treating and/or preventing these injuries, several researchers have taken it upon themselves to determine what movement patterns predispose athletes to developing these conditions. This research indicates that greater knee abduction moments9,10, peak hip internal rotation11, and hip adduction motion12 are risk factors for PFPS development. Whereas, for ACL injury, Hewett and colleagues13 conducted a prospective cohort study identifying increased knee abduction angle at landing as predictive of injury status with 73% specificity and 78% sensitivity. Furthermore, as the risk factors for developing both disorders are eerily similar, Myer et al performed a similar prospective cohort study finding that athletes demonstrating >25 Nm of knee abduction load during landing are at increased risk for both PFPS and ACL injury14.
Does Weak Hip Strength Correlate to Knee Pain?
With a fairly robust amount of research supporting a hip etiology in the development of these injuries, it would make sense that weakness of the hip musculature would also be a risk factor, right?
A recent systematic review found very conflicting findings on the topic. With regards to cross-sectional research, the findings were very favorable with moderate level evidence indicating lower isometric hip abduction strength with a small and lower hip extension strength with a small effect size (ES)15. Additionally, there was a trend toward lower isometric hip external rotation and moderate evidence indicates lower eccentric hip external rotation strength with a medium ES in individuals with PFPS15. Unfortunately, the often more influential prospective evidence told a different story. Moderate-to-strong evidence from three high quality studies found no association between lower isometric strength of the hip abductors, extensors, external rotators, or internal rotators and the risk of developing PFPS15. The findings of this systematic review indicated hip weakness might be a potential consequence of PFPS, rather than the cause. This may be due to disuse or fear avoidance behaviors secondary to the presence of anterior knee pain.
Does Hip Strengthening Improve Hip Biomechanics?
Regardless of its place as a cause or consequence, hip strengthening has proved beneficial in patients with both PFPS16,17,18 and following ACL Reconstruction19, but does it actually help to change the faulty movement patterns?
Gluteal strengthening can cause several favorable outcomes, from improved quality of life to decreased pain, unfortunately however marked changes in biomechanics is not one of the benefits. Ferber and colleagues20 performed a cohort study analyzing the impact of proximal muscle strengthening on lower extremity biomechanics and found no significant effect on two dimensional peak knee abduction angle. In slight contrast however, Earl and Hoch21 found a reduction in peak internal knee abduction moment following a rehabilitation program including proximal strengthening, but no significant change in knee abduction range of motion was found. It should be noted that this study included strengthening of all proximal musculature and balance training, so it is hard to conclude that the results were due to the strengthening program and not the other components.
Does Glute Endurance Influence Hip Biomechanics?
All this being said, it is possible that gluteal endurance may be more influential than strength itself, so it would make sense that following isolated fatigue of this musculature, lower extremity movement patterns would deteriorate.
Once again, this belief is in contrast to the available evidence. While fatigue itself most definitely has an impact on lower extremity quality of movement, isolated fatigue of the gluteal musculature tells a different story. Following a hip abductor fatigue protocol, patients only demonstrated less than a one degree increase in hip-abduction angle at initial contact and knee-abduction angle at 60 milliseconds after contact during single-leg landings22. In agreement with these findings, Geiser and colleagues performed a similar hip abductor fatigue protocol and found very small alterations in frontal plane knee mechanics, which would likely have very little impact on injury risk23.
Can We Really Blame the Glutes?
The biomechanical explanation for why weakness or motor control deficits in the gluteal musculature SHOULD cause diminished movement quality makes complete sense, but unfortunately, the evidence at this time does not agree.
While the evidence itself does not allow the gluteal musculature to shoulder all of the blame, this does not mean we should abandon addressing these deficits in our patients. As previously stated, posterolateral hip strengthening has multiple benefits, but it is not the end-all-be-all for rehabilitation or injury prevention of lower extremity conditions. Proximal strength deficits should be assessed through validated functional testing in order to see its actual impact on lower extremity biomechanics on a patient-by-patient basis. Following this assessment, interventions should be focused on improving proximal stability, movement re-education, proprioception, fear avoidance beliefs, graded exposure, and the patient’s own values, beliefs, and expectations.
John Snyder, PT, DPT, CSCS received his Doctor of Physical Therapy degree from the University of Pittsburgh in 2014. He created and frequently contributes to SnyderPhysicalTherapy.com (Formerly OrthopedicManualPT.com), which is a blog devoted to evidence-based management of orthopedic conditions.
John provides an excellent review of many common beliefs in regard to the influence of the hip on knee pain. While it is easy to draw immediate conclusions from the result of one study or meta-analysis, one must be careful with how they interpret date.
I think “anterior knee pain,” or even PFPS, is just too broad of a term to design accurate research studies. It’s going to be hard to find prospective correlations with such vague terminology. Think of it as watering down the results. Including a large sample of people, including men, women, and adolescents and attempting to correlate findings to “anterior knee pain” is a daunting task.
Imagine if we followed a group of adolescents from one school system for several years. Variations in gender, sport participation, recreational activity, sedentary level, and many more factors would all have to be considered. Imagine comparing the development of knee pain in a 13 year old sedentary female that decided she wanted to run cross country for the first time with an 18 year old male basketball player that is playing in 3 leagues simultaneously. Two different types of subjects with different activities and injury mechanisms. But, these two would be grouped together with “anterior knee pain.”
What do we currently know? We know hip weakness is present in people with PFPS and strengthening the hips reduces symptoms. As rehabilitation specialists, that is great, we have a plan. I’m not sure we can definitely say that hip weakness will cause knee pain, but I’m also not sure we can say it won’t. Designing a prospective study to determine may never happen, there are just too many variables to control.
John does a great job presenting studies that require us to keep an open mind. I’m not sure we can make definitive statements from these results, but realize that there are likely many more variables involved with the development of knee pain. Hip strength and biomechanics may just be some of them. Thanks for sharing John and helping us to remember that it’s not always the glutes to blame!
Most people know that one of the keys to successful baseball pitching is a consistent release point. This is a point that is driven home by coaches all the time. Most people focus on your arm slot, for good reason. Many times inconsistency in your arm slot can be the major cause of poor biomechanics and difficulty repeating your delivery. I see this a lot in young baseball pitchers that are trying to tweak their mechanics and pitchers that may have discomfort in their shoulder or elbow and are trying to take some pressure off the sore area.
However, the act of throwing a baseball is a sequence of kinetic chain events that ultimately lead to your release point. There are several factors with your lower body and core that may be altering your arm slot and leading to an inconsistent release point without you even realizing.
5 Mobility Issues That May Prevent a Consistent Release Point
In this article I will discuss 5 issues that may be preventing a consistent release point while pitching. There are several areas that can be causing inconsistency, but I wanted to focus on mobility and stability issues that you can address.
If you have mobility or stability concerns in your lower half and core, your body is going to make the adjustment with your arm in order to throw a strike.
This is far too common and one factor in injuries in my opinion. These compensations are going to lead to wear and tear as well as decreased performance.
It is going to be difficult to make adjustments to your mechanics before cleaning up and mobility or stability concerns. Otherwise, you are kind of running up hill (or should I say throwing up hill?) trying to make mechanical adjustments on top of dysfunction.
Inconsistent Lead Knee Flexion and Trunk Flexion
A very interesting biomechanical study was conducted by ASMI that looked at biomechanics over the course of a game to see if arm slot and a consistent release point changed. What they found was pretty interesting. Over the course of a game as the pitcher became tired, there was no change in arm slot at all biomechanically. In fact, there were relatively little biomechanical changes over the course of a game. However, they did find two things – a decrease in lead knee flexion and a decrease in trunk flexion.
As baseball pitchers get tired over the course of a game, their bodies are more upright.
This leads to a higher and inconsistent release point, but it has nothing to do with the pitcher’s arm slot. Their arm slot was the same, but their release point was higher. This is a very important factor in understanding why a pitcher leaves his pitches up and has trouble getting the ball down in the zone late in the game.
This really demonstrates the importance of a few things:
Lead leg quad and hip strength
Lead leg quad and hip endurance
Lead leg single leg stance stability
In addition to strength and endurance, I will also incorporate basic lunges onto an unstable surface, such as below, and progress to more dynamic activities over time.
I also work on low back and posterior chain endurance and stability. Here is an example of a drill to work on a consistent trunk flexion angle. The bands create a force trying to pull the trunk forward, creating a need for the body to stabilize.
Restricted Lead Hip Mobility
Another issue with the lead leg involves mobility as the baseball pitcher’s body rotates and transitions their body weight from the rear leg to the front leg during arm cocking and acceleration phases of throwing and then release the ball and travels into the arm deceleration and follow through phases.
During this movement, the body must rotate over a planted lead leg into a position of hip flexion, adduction and internal rotation. This is a challenging position to achieve and goes against our postural adaptations, so many baseball pitchers struggle to “get into their lead hip” in this fashion.
Any limitations in lead hip mobility is going to prevent the pitcher from closing their body. This can cause them to fly open, become more rotational, have their arm drag behind their body, or to decelerate with more of their arm and less of their lower half. All of these are not good things!
I use several drills and emphasize this “getting into your hip” position. Here is one basic mobility drill to encourage this hip mobility. The athlete stands in a split stance similar to their release point and rocks in and out of their hip. The coaching cue here is to pull your lead leg back into your hip.
For those that have more restrictions and can’t get into their hip well, they may need more posterior hip stretches, such as shown below. One thing of note is that I want the lead leg that you are stretching close to neutral rotation. It’s hard to get into this position without going into hip external rotation, but I do not want the hip externally rotated like you see in many common runner stretches. You can alter the area of mobilization but changing your body angle to the side and forward until you feel it in the rear of your hip.
Restricted Rear Hip Mobility
Most pitchers realize that stride length is going to have an effect on release point. While stride length often times is due to other biomechanical and timing issues, there is a potential for rear leg adductor tightness (groin) altering your stride length.
In my experience, this tends to occur more when there is a groin or hamstring injury in the rear leg or in the pitcher with hip impingement. I have even seen some pitchers with chronic MCL issues on their rear leg, especially in those with aggressive toe drag.
These concerns will obviously have to be addressed, but there are some general hip mobility drills that you can perform to maintain and enhance adductor mobility in the rear leg. Here are two basics that are easy enough to add to your movement prep and dynamic warm up, adductor foam rolling and mobilization.
Poor Rear Leg Stability
In addition to restricted rear hip mobility, the rear leg also has to stabilize the weight of the body at the top of the wind up when the lead leg reaches peak height. While this seems fairly basic to most people, it could be the equivalent of doing 200 single leg stance exercises for a starting pitcher if you include warm up. Your balance point at the top of the wind up is essential for the proper sequencing of the rest of your delivery.
Top bring physics into the discussion, your balance point is also where you start developing potential energy and transitioning to kinetic energy. To illustrate, when you draw back a bow you are building up potential energy to shoot an arrow. The more you pull back, the more energy you develop and eventually transfer to the arrow. Losing rear leg stability is the equivalent of drawing the bow back half way. You will lose some of that energy and force that you want to put behind the ball and direct towards the plate.
So, any issues with rear leg stability could lead to issues with power development, timing, and sequencing through the rest of the delivery requiring your arm to “catch up” to find the correct arm slot. This can be seen in people drifting and even some that drop-and-drive.
In addition to lower half strengthening exercises, I try to incorporate balance as well. Here is an example of just some basic single leg balance on an unstable surface. The foam pad simulates the decline of the mound. The goal is to pause at the top, maintain balance, and then control your body lowering back down to the start position. This is a quality over quantity drill.
Poor Core Control
As you are probably noticing, developing force towards the plate is a common theme in this article. Any energy leaks away from the plate are going to alter your mechanics and take away from your potential. Poor core control is one of the most common energy leaks I see, especially in young and/or loose pitchers. Core control seems to take longer to develop in young athletes, even as they get strong. Perhaps it has to do with growth spurts, but regardless, it appears that younger athletes have difficulty controlling their core during functional activities. Add the speed of pitching into the mix, and this core control is challenged even further.
For the loose athlete, they tend to rock back onto their joints to gain stability to make up for poor core dynamic stability. In the core, this is often seen in pitchers that arch their back significantly while pitching. This is often lack of anterior core control, taking your momentum away from the plate and becoming more rotational. This can alter your arm slot and put significant stress on not only your arm, but also you low back.
There are a lot of anti-extension exercises, such as planks and dead bug sequences, that should serve as the basic foundation for this core control. But once baseline core control is established, I tend to try to get the athlete in more specific positions. Here are a couple of anti-extension exercises in the stride position. The bands are pulling into extension, requiring the body to provide anterior core control. I will progress to then use a TRX Rip Trainer so that I need to prevent a combined extension and rotary force.
Before you start focusing on your arm slot to train a more consistent release point, make sure you have adequate mobility and stability below. I always recommend a thorough evaluation combined with manual therapy and some of the corrective strategies above (My Functional Stability Training series has many more examples of these drills and more). Don’t forget that you may have some mobility and stability issues with your lower body and core that may be causing and inconsistent release point and making it difficult to repeat your mechanics.
I read a lot of stuff on the internet. I like to keep up with a ton of blogs, websites, and journals to make sure I am on top of recent trends, but also to share with my readers. I recently came across an article at Science Direct entitled Getting Athletes Back in the Game Sooner Following Shoulder Injuries. Nice headline, right? It made me want to click.
Interestingly, they were talking about how a biceps tenodesis can cut down the rehabilitation time from SLAP tears in comparison to a SLAP repair. That wasn’t what I was expecting!
OK, would a tenodesis cut down (no pun intended…) the rehab time in comparison to a SLAP repair? No doubt, I agree with that. But I am not sure if this is what we want to do, especially in athletes, as the title of the article suggested. Let’s dig into this deeper, but first, let’s discuss SLAP tears and what the biceps tenodesis surgery actually does.
What is a SLAP Tear and Biceps Tenodesis?
I’ve covered superior labral tears, or SLAP tears extensively in the past. If you don’t know much about SLAP tears, start there, but essentially a SLAP tear is a superior labral tear at the junction of where the long head of the biceps comes in and attaches to the superior labrum. SLAP tears are common, and can be especially troublesome for overhead athletes. (Photo from Wikipedia)
A biceps tenodesis is a surgical procedure that detaches the biceps attachment from the superior labrum and reattaches it to the humerus. Here is a surgical demonstration from Smith and Nephew:
By removing the biceps, this essentially eliminates the patient’s pain from the SLAP lesion or biceps tendonitis, however at what consequence? By performing a tenodesis, you are changing the anatomy of the shoulder and the function of the biceps. This procedure has become more popular in older individuals, essentially those that chose a decrease in function for a decrease in pain. But what about athletes, as the paper I mentioned above proposed was happening, can they return to sports faster by simply cutting the biceps off instead of trying to repair it?
One of the most popular studies on this subject was in AJSM in 2009. The authors reported that the results of biceps tenodesis were superior to SLAP repairs in athletes with superior labral tears. The authors mention both “overhead athletes” and “return to sport” in the paper, though they report the age range of subjects was 24-69 years old. Furthermore, significant differences in age existed between the two groups, with the mean age of 37 years old in the SLAP repair group and mean age of 52 years old in the biceps tenodesis group. One could certainly argue that the level of “sport” participation was different between the groups and could certainly influence their subjective satisfaction.
What is the Function of the Biceps?
Biomechanical studies have shown that the biceps labrum complex has a role in providing both translational and rotational stability, and that repair of a SLAP lesion restores this ability to provide static stability. This is especially true in overhead athletes who need to use their arm in the abducted and externally rotated position. Contraction of the long head of the biceps in this position has been shown to reduce anterior humeral head displacement, a functional that is critical in preventing throwing injuries. In fact, peak biceps EMG activity has been shown to occur during this cocking phase of throwing, and has been shown to be higher in pitchers that have anterior instability.
So if the biceps is involved with translational and rotational glenohumeral stability and helps prevent superior humeral head migration, is this something you want to sacrifice just to reduce pain? How will this impact function, and more importantly, future injuries?
Is a Biceps Tenodesis the Answer?
Is there a role for biceps tenodesis? I am sure there is. I like the recommendations my friend Brian Busconi reports in this paper, stating that he likes to perform SLAP repairs, but will consider biceps tenodesis in patients over the age of 45. This serves a different purpose and return to high level athletics is probably not as important to the patient than reducing their pain. I have heard Dr. Altchek from New York report in meetings that he thinks biceps tenodesis may be an option, but one he reserves for those who fail a SLAP repair. Still, I have to wonder what the long term effects of the biceps tenodesis will do on this patient population as well. Will the increased superior humeral head cause rotator cuff pathology or degenerative changes? Only time will tell.
Noted orthopedist, Dr. James Andrews was recently asked about the biceps and the potential for biceps tenodesis, to which he replied “The biceps is there for a purpose — it’s too intrinsically associated with the shoulder joint. Until we know what the real function of it is, we’re stabbing in the dark.” When asked if a biceps tenodesis is the answer to athletes returning to sport, similar to a Tommy John procedure, he replied “With Tommy John surgery, we’re actually restoring anatomy. In the case of biceps tenodesis, you’re deleting anatomy.”
SEE ALSO: Dr. Lyle Cain from Dr. Andrews’ American Sports Medicine Institute discusses some of the facts and fiction related to the biceps tenodesis surgery.
So, sadly, I don’t think we all learned a great new way “get athletes back in the game sooner following shoulder injuries” like the Science Direct title would suggest. Perhaps I’m wrong, but I would have to agree with Dr. Andrews, I always prefer procedures that restore anatomy when possible. Don’t get me wrong, a biceps tenodesis has it’s place. But I’m not sure if it is the magical secret to getting athletes back faster, there just has to be some consequences.
What has your experience been? Have you seen many athletes opt for a biceps tenodesis rather than a SLAP repair?
This week’s Stuff You Should Read comes from Chris Beardsley, T-Nation, and Pete Holman.
ShoulderSeminar.com, Inner Circle, and RehabWebinars.com Updates
My huge sale on ShoulderSeminar.com rages on! Thanks for those that have joined already, you are going to really enjoy the next 7 weeks of my online program. Get $150 off the price of enrollment plus free access to RehabWebinars.com if you sign up be the end of October. Don’t forget it is worth 20 CEUs for the NSCA and 21 for the NATA and MA state APTA. Click here to learn more about the limited time offer.
My next Inner Circle webinar will be on How I Use Kettlebells in Shoulder Rehabilitation. This isn’t going to be how traditional kettlebell exercises, like swings, can be used for shoulder work, but rather how I use kettlebells as a tool to strengthen and enhance stability of the shoulder for people with injuries. I’m still trying to solidify a date and time but will post the info when scheduled in the Inner Circle Dashboard. Check it out and click here to learn more about the Inner Circle.
We had several new webinars this week featuring Pete Holman, PT, CSCS. Pete is the Director of Rip Training at TRX and shares three webinars on some really cool exercises techniques to train rotational power in athletes, to strengthen the posterior chain, and to focus on shoulder prehab work. Good stuff and really great technique demonstrations. I’ll be featuring a post with Pete next week here at MikeReinold.com. Click here to learn more about RehabWebinars.com.
Chris Beardsley of Strength and Conditioning Research has a very thorough breakdown of the biomechanics of adding weight to the lunge. This is a really great article that outlines the role of the hip extensors during the forward lunge.
What do you get when you get 8 experts on heart rate variability training to sit around a round table and discuss HRV? A HRV roundtable discussion! This is an information article for those new to using HRV, which is something to explore as we learn more and more about recovery, stress, and the impact on performance. You should read this to start thinking about how you can use HRV to get the most out of your clients and athletes.
The TRX Suspension System is a pretty cool piece of exercise equipment that has some obvious (i.e. rows!) and not so obvious uses. The strength community has shown us tons of great uses of the TRX, but I also personally use the TRX many ways within my rehabilitation programs.
Here is a video of some simple variations to the squat that can be performed by using the TRX. I’ll explain more about why I use these TRX squat variations below, but take a look at the clip first:
Muscle Activity During Squats
Biomechanical studies have shown that altering your center of gravity impacts the resultant muscle activity ratios between the quadriceps and hamstrings. This was demonstrated well in the classic 1996 study by Wilk, Escamilla, and Fleisig publish in AJSM. The authors compared squatting and leg press and found that the plane of orientation of the body produced a significant effect on muscle activity.
During the upright squat, when the center of gravity is fairly neutral, the quadriceps and hamstring muscle groups produced a relative amount of co-conraction during the concentric portion of the exercise:
However, when the leg press was performed and the center of gravity was positioned posteriorly, the contribution of hamstrings to the activity was significantly less:
Basically when performing an exercise where you center of gravity is posterior, such as a leg press or wall squat, you will increase quadriceps activity and decrease hamstring activity. Conversely, if you lean forward during a squatting motion, you will increase the hamstrings contribution. Lastly, a neutral squat with a neutral center of gravity will produce co-contraction of the two muscles.
TRX Squat Variations
These biomechanical findings can be used to alter the ratio of quadriceps to hamstrings during the squat as needed. Clinically, there are times during the rehabilitation process where this may be beneficial.
For example, a patient recovering from ACL reconstruction surgery may benefit from performing neutral squats to facilitate co-contraction and stability of the knee. A patient with a PCL injury may want to perform squats from to neutral to posterior to their center of gravity to reduce hamstring contribution and the potential for posterior shear forces. If you want to facilitate posterior chain involvement during the squat and emphasize hip extension, you may want to lean forward and work on this motor control pattern.
As you can see there are a lot of potential clinical implications.
Using the TRX to perform these squats is very helpful, expecially during the early phases of rehabilitation. The TRX suspension system can take some weight off the squat, enhance balance so the patient can shift their center of gravity more anterior or posterior, and serves as what I like to call “training wheels” to help perform a squat correctly when movement dysfunction exists. Just a small reduction in body weight can enhance motor control and help movement quality during the squat. As the person’s motor control improves, they can ween off the TRX “training wheels.”
What do you think? How have you used the TRX during rehab? These are just a few examples of how using the TRX suspension system can help us tweak an exercise like the squat. Understanding the biomechanics of the squat and what happens on the inside during these TRX squat variations will help us build better programs for our patients and clients.
Mike is the President and Co-Founder of Champion Physical Therapy and Performance, located in Boston, MA. Champion offers an integrated approach to elite level physical therapy, personal training, and sports performance.
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