Box Jump Mechanics after ACLR: after a month of training

We discussed an example of poor box jump mechanics after ACLR. It is shown in many studies that poor jump mechanics is a risk factor for an injury. But it can be fixed through training. 

The picture on the left is taken earlier. She was jumping with her knees almost touching. She also landed on the box with the same knee positions. The picture on the right was taken after about a month and a half after. She is still going through rehabilitation but her jump mechanics is a lot better. She also is not standing straight up like she was on the left picture. She still leans towards her non-surgical side when she jumps, which needs to be fixed.

Box Jump Mechanics after Knee Surgery

There are a lot of research studies done on jump mechanics. It can tell us a lot of different things. Jumping with wrong mechanics is a risk factor for an injury, not ideal for performance, may indicative of insufficient muscle strength, etc. The athlete may be compensating, not feeling comfortable jumping, or scared. 

       There are so many things that we look at when evaluating jump mechanics. We look at it from the front. We look at it from the side. We look at how much the knees and hips are bent when they land. We look at where the feet re pointing, etc. One thing that we evaluate when looking at the athlete from the front is where their knees are when they take off and when they land. The pictures below are showing a basketball players jumping to a box. Her knees are almost touching each other when she takes off. 

 Also, we can tell that she is leaning towards her right leg which is her healthy knee. She is rehabing from a knee surgery and has good quads and hamstrings strength and training her hip muscles as well as balance, squatting mechanics, etc. So, why is not jumping the right way?! She may not be able to use her muscles, or she is so used to jumping this way for a long time, or there are other  potential factors that her jump mechanics is not the way it should be. Whatever the reason  may be, as a rehab professional, we need to find out why and fix this because we know, from the past literature, this is not a good sign and this may predispose her to another injury in the future.

Generalized Joint Laxity and Injury

There are so many research studies that investigated relationship between loose jointed athletes and injury. Some say there is a link and the others say no. We did a research on it too using female volleyball players and found athletes with a history of injury such as ankle sprain were loose jointed. You can read our published article here.

Core Stability Exercise

Everyone knows that it is important to train core muscles. However, people tend to misunderstand when it comes to how to train those muscles. Understanding the importance of core is important, but you need to train it the right way also. To me, injury prevention and performance enhancement training is based on the idea that every joint and body segment should have enough motion but should not have too much motion in isolation and during movement. Some parts of the body are supposed to move and some are not supposed to move a lot. When a part of the body that is not supposed to have a lot motion moves too much, it can lead to an injury or decreased performance. And the core is one of those that should NOT have too much motion. So, when doing a core exercise, you should really focus on keeping your pelvis and lumbar spine stable instead of focusing on how much and how fast you can move your arms and legs, or trunk, or how much weight you can lift.

Here is an example......

This exercise looks simple but not easy for a lot of athletes to do it right. Starting from laying on a physio ball (top picture), you try t extend one knee (bottom picture) WITHOUT losing balance, dropping a hip or hips, keeping pelvis squared to the floor, and maintaining neutral spine position. Like I said, this exercise is NOT about how fast you can move your leg, but how stable you can keep your pelvis and spine and whole body. 

 

Postural Stability and Control

Postural stability and control is an important factor when it comes to injury prevention and performance enhancement. Athletes will have to be able to stabilize, control, and maintain it. The better they are able to do it, the less risks of injury they will have and the better they will be able to perform no matter what the tasks and skills are. This is a main reason that a gymnast falls off from the beam, a figure skater doesn't land a triple jump, a soccer player hurts her knee, etc. To have a good postural stability, athletes will have to have enough strength, musce balance, proprioception, and they also need to be able to recruit muscles when they need to at a right timing. They will also have to have endurance to maintain it for a prolonged period of time. There are a lot different ways to achieve this and also depending on what their deficits may be, training methods will vary. But this is one of my favorite exercises to have an athlete do.

You stand on BOSU ball or something that challenges you to balance on and get in a squat position, holing a stretch exercise band attached to a wall at your shoulder height. Then, you extend the arms out as you maintain the good squat position without letting the BOSU ball tilt. Bring the arms back in towards your body and repeat. Also, keep in mind to maintain the neutral pelvic position.

Sounds easy?! Give it a try and find out!

Tennis Serve vs Baseball Pitching

Tennis players and baseball players especially pitchers are called "overhead" athletes because of the way they throw the ball and serve. Tommy John surgery in baseball pitchers is one of the most talked about injury in all sports right next to concussion these days. However, we do not hear anything in tennis players. There are a lot of similarities between baseball pitching and tennis serve, and they both suffer similar shoulder injuries. But why don't tennis players suffer Tommy John injury?! Everyone that watches or plays baseball has heard of "pitch count", however, we don't hear about "serve count" Let's take a look at how many pitches a starting pitcher throws in a month. They usually get 5-6 starts a month and they pitch around 100 pitches per start. So that's roughly 500-600 pitches per month discounting bullpen sessions they do between starts. Tennis players' serve count varies depending on how many matches they win in a tournament. After looking at 250 Grand Slam matches from 2014-2016, male tennis players served 140-150 times a match on average. Those players that advanced to the round of 16 played 4 matches in about a week. So that is 560-600 serves in a shorter period of time. A baseball is heavier than a tennis ball. Tennis players use a tennis racket. 

       One thing that stands out to me is that during baseball pitching pitchers shoulder is rotating at around 5-7000 degrees per second. On the other hand, tennis players shoulder are rotating at a lot slower speed (4-5000 degrees per second). The faster you move the shoulder, the more stress you are placing on the shoulder and elbow. Also, tennis players can use a tennis racket to serve harder than baseball pitchers can throw a baseball. 

       There is no study that explains why baseball pitchers suffer more Tommy John injury than tennis players. So we can  only speculate, but shoulder rotation speed may have something to do with it. Also, tennis players seem to suffer more wrist injuries than baseball pitchers. Tommy John injury is more common in athletes such as javelin throwers than tennis players. And studies suggested that softball pitchers suffer similar shoulder injuries to those suffered by baseball pitchers even though softball pitchers pitch underhand.......

Preventing Injuries

An injury is something that many athletes are forced to deal with at any level of play whether it is at junior level, high school level, college level, or professional level. Some injuries are more serious than others. But if you have to deal with pain every time you practice or if you have to miss practices and competitions, it is not fun. In many cases, an injury is caused by multiple factors; some you can control (intrinsic) the others you can't(extrinsic). As long as you want to play sports competitively and achieve your goals in the sport, you should be involved in some form of injury prevention program because it is the first step toward success.
      Everyone talks about "core" these days and does some type of core exercises to become a better athlete. But why is it and how is it important?! "Core" is pelvis and lumbar spine (and sacrum). And muscles that are attached to them are called "core muscles". Some parts of the body are designed to move and the others are not. Pelvis, sacrum, and lumbar spine are those areas that should have minimal movements, which means that you should be able to control their movement and stabilize them, which requires muscles  functions. There is a study done on baseball pitchers to see how the amount of pelvis motion affects their performance (ERA, WHIP, etc). And they found that the pitchers that had 7 degrees or more tilt of pelvis during the measurement pitched worse than those that had less than 7. Another study suggested that tennis players with low back pain had more movement of pelvis in a sagittal plane than those who did not have low back pain. Of course, core stability alone will not prevent injury or enhance performance, however, core stability is a huge factor in those two areas. 
       Any athletes that are involved in competitive sports should implement injury prevention program and core strength/stability/endurance/proprioceptive exercises should be included in it. 

Single Leg Squat Test

A lot of athletes use single leg squat as an exercise and strength training. However, oftentimes, we see them do it wrong... knowing what the right form is is one thing and being able to do it right is another. We use single leg squat as a test to identify what the athlete is doing, being able to do or unable to do, what the athlete may need to work on, whether the athlete may be at a risk of injury, etc. We take a video of an athlete doing a single leg squat from the front and the side and put in on slow motion motion analysis app to assess it. 

This is how this figure skater stood on single leg. Other than her toes/foot pointing out slightly she was comfortably standing with a good balance. Then, I asked her slowly squat down and come back up... then this is what happened (shown in the picture below). 

She was having hard time balancing on her leg. Her knee collapsed. Her knee was going over her toes. It was really challenging for her.   

Figure skaters spend a lot of time on ice on single leg. If this is what happens when they jump and land etc, not only will this keep them from performing well but also will lead to increased risk of injury. And if they have trouble performing single leg squat on the ground slowly, they would have much harder time doing this on ice. But the question is.... why is this happening?! It could be from a lot of different reasons and from combination of multiple contributing factors. Some of the most common contributing factors are hip muscle weakness, arch is collapsing, poor muscle strength and balance, etc. A rehabilitation specialist should be able to identify why this is happening in each athlete and fix it. Each case is different and there are additional tests we can do to find out why this faulty maneuver is happening. Or maybe this is what she or he is used to doing.

From performance and injury risk standpoint, this is a huge disadvantage because 1) figure skaters have to be able to jump without using their ankle while skating on ice 2) they have to absorb an impact that is 6-7 times of their body weight without using their ankle on one leg. And in most cases, this is something that needs to be fixed during off ice training.

Kinesio Tape

Kinesio tape  has been around for a while now and is getting more popular these days as  it is getting more exposure on TV and social media etc. I have ignored it for a while because there is no scientific explanation to why and how it works. However, there have been a lot of research studies that support that it works and getting more difficult to ignore. According to the past studies, it may reduce pain, increase range of motion, increase strength, reduce swelling and ecchymosis (bruise), etc. What we do not know yet is its physiological effects on the body (if there is any...). Could it just be psychological?! Possibly.. But let's say you get injured or aggravated your old injury in the middle of tournament or competition and need to get through it.... if using kinesio tape helps with pain etc, why not use it. But at the same time, you do not want to keep masking the symptom using kinesio tape or NSAIDs instead of taking care of what caused the pain or injury. Kinesio taping could be useful in certain cases. Here is an example of kineio tape applied for wrist flexor tendonitis at medial elbow. 

Movement Impairment (1)

Have you had any pain and saw the doctor but were told that there was anything wrong?! Have you had pain that gets better with rest but comes back as soon as you start using the body part?! There is probably nothing more frustrating as an athlete than having pain that keeps you from training and competing but no one can figure out what is really going on. It is a lot easier to understand why you are having pain when you see what is damaged on a film such whether it is broken bone or torn ligament. However, there may be a lot more to "pain" than pain caused by injuries diagnosed by the doctor. Let's say there is a female figure skater with chronic lower pack pain. Her back is fine as long as she keeps her training  short, however, her pain increases as her training intensity and length increase. Her doctor took an x-ray and MRI of her back but did not see anything wrong with her back structurally. So she was told that she was fine and keep training as pain permits. So in her case, is she really fine?! Or is there something wrong that did not show up on the films?! The fact that she has pain that keeps her from training is not "fine". There must be something wrong. But what is wrong with her that even her doctor could not find?! First of all, lower back is where she is having pain and may not necessarily be where a cause of pain is. Then, where is her pain coming from?! This is something we, rehabilitation specialists, can or should be able to find and fix so she will be pain free. We examine things such as flexibility, muscle strength, range of motion, core stability, feet, posture, etc etc etc to name a few. One of the things we look at is how  her body is moving or the way  she moves her body. And what movement(s) she is having trouble with, having pain with, is not doing right, etc. And what movements she has no pain with. Having strong muscles and strength and good range of motion is one thing. But how she is using  those in a system during movements is another story. Every body movement happens in a system, which means that each part of the body/segments have to work in sync to optimize the movement and to prevent stress from being placed on the body. The human body is very well balanced withing asymmetries that we have. Our body is not completely symmetrical but well balanced. So, if a part of the balance system fails, this can be a problem. Doing a certain movement wrong a few times are not likely to cause pain right away, but if that happens over a long period of time, this can be a problem. There are a lot of things that may have caused her lower back pain. But just because the pain is not diagnosed or there is no structural damage, this does not mean there is nothing wrong. Bottom line is... pain is a sign that there is something wrong and it is very important to figure out what is really causing the pain and fix the contributing factors. Otherwise, it will keep coming back. 

Speed Isn't Everything: Tennis Serve

In sports such as baseball and tennis, athletes tend to improve on pitch speed and serve speed. And it is important to have enough speed, however, it may not be everything you need to have when it comes to professional sports. We analyzed more than 200 match stats from this year's Grand Slam (Australian, French, Wimbledon, and US opens). We have found that the winners' average 1st serve speed was about 183km/hr and also that the losers served about 183km/hr on average. The 2nd serve speed was 149km/hr for the winners and 148km/hr for the losers. What was different between winners and losers were that the winners won about 77% of their 1st serve and the losers won only 65%. Also the winners won 56% of their 2nd sere points and the losers won only 45% of them. This tells us that serve speed was not everything in those Grand Slam matches. There has to be something else that matters other than the speed. Ball location, serving strategy, and ground stroke, etc etc. This just tells us that serve speed isn't everything in tennis and probably the same for sports such as baseball at least in a professional level.

Gravity in Sports

Most people do not like physics and chemistry and math and.... all those things we all learn in school. Most of us wondered why we had to learn all that. Sometimes knowing a little about physics won't hurt us..... Yes! Even in sports! We all know what the gravity is and all know that it exists every where we go on Earth. And it's constant everywhere. And it is FREE to use!! The gravity can be your best friend or your enemy. It depends on how you use it. When we do rehabilitation and exercise, we think about the gravity all the time to effectively and efficiently use it or to eliminate it. Let's say you are being measured for a max vertical jump. When you are standing straight on the ground, you are experiencing something called ground reaction force (GRF) which is the same as your body weight. Your weight pushes down on the ground and the ground pushes you back up. That's why you are not sinking into the ground or you are not being pushed up in the air. How high you can jump depends on how well you can use GRF. How well you can maximize it and how efficiently you can use it. Athletes with more weight potentially have more GRF they can use because GRF varies with body weight. However, they have to be stronger to be able to jump because they are heavier. So how can we maximize it? Stand on a scale and see how much you weigh...staining straight...and then try moving your arms up and down or bend your knees. You should see the number of the scale go up for a moment. That's one way to jump higher. Use your legs and arms. Another way to do that is to do a little hop before you jump up (this is usually not allowed when you are being measured though). Any object in the air has something called potential energy and it depends on its mass and its height. When you hop straight up before you jump, you are creating an extra energy that you can use because when you land from the hop, GRF is higher. Try hopping on a scale (without breaking it) to see what happens when you land on it. However, a flip side of this is that when you jump you have to land too. The higher you jump, the bigger the force your body feels and needs to absorb is. A good thing is that you have shock absorbers in your own body...muscles. Muscles are like springs. They can create a force for you to use and can dissipate it. A lot injuries happen during landing and its cause is multi-factorial. A failure to absorb a force when you land will put stress in your body (joints, muscles, bones, etc) If you do not land in a right way, your body will feel extra stress that you may not feel when you land correctly. Over time, it could lead to an injury. You also have to have enough muscle strength to do it. You need to have right muscles working at the right time too. Bad mechanics will interfere with it. Especially in sports where jumping is a major part of, it becomes even more important to be able to utilize the gravity and also able to protect your body from it. Gymnastics, volleyball, figure skating, basketball, etc etc etc. Hope this makes a little sense. The gravity can be your best friend or can be your worst enemy. But it is up to you to make it your BFF!!!

Stress Fracture in Figure Skaters

This figure skating season is nearing an end as only a few more international and national level competitions are left. Also, this is about time of the season when athletes get injured as an intensity of competitions increases. Those skaters who qualified for the nationals are probably training harder to do well in the competition. Some may be trying to secure a spot at the Worlds. Or some may already been training for the next season. Training hard is necessary to be successful. However, training too hard can be potentially damaging to the body. One of the common injuries suffered by figure skaters is stress fracture. The common injury sites are foot, lower leg, hip, and lower back. Stress fractures are categorized into 2 categories. One is a high risk fracture and the other is a low risk fracture, depending on where the fracture is located. High risk fractures are treated more aggressively because of their higher chance of non-union fracture. Many cases may require a surgical fixation of the fracture. Low risk fractures are usually treated with relative rest, partial or non weight bearing, activity modification, and rehabilitation. In case those do not work, then, it may be treated more aggressively. One of the reasons why it makes it challenging is that a lot of skaters will ignore a pain and keep training until it gets to the point that they cannot. By the time it becomes that painful, it may be too late. Once diagnosed with a stress fracture, a skater will be off the ice for a long time, probably around 6 weeks to a few months. Good news is that it is preventable. Causes of stress fractures include sudden increase in training intensity and time, a change of skates, nutritional factors, over training, not having proper mechanics, etc to list a few. Female skaters are more prone to stress fracture than male skaters. A study done at BYU showed that figure skaters sustain about 8 times of their body weight when they land on ice from a jump. That means that they have to be able to sustain that much force only using knee and hip muscles (and core muscles play an important role as well). When we jump and land on the ground, we can use ankles, knees, and hips and muscles around them to absorb the force. However, when skaters jump on ice, they are forced to use only knee and hip because of rigid type skates they wear. It becomes very important that they have enough muscle strength in their knees and hips to sustain that much force. By being evaluated for any risk factors they may have and by eliminating those factors when they are healthy, injuries such as stress fracture can be prevented.

Pitch Count in Professional Baseball Pitchers: USA vs Japan

There have been so many injuries in MLB about a half way through the season especially UCL tears, the most recently a NY Yankee pitcher, Tanaka. A lot of people in baseball world including coaches, media, and medical staff are discussing that pitchers in Japan pitch too much and they will get hurt. A pitch count is strongly reinforced in the US including little league baseball and professional baseball. However, it is not in Japan. Especially high school baseball in Japan is so popular and it is not rare that a single pitcher pitches a complete game in 6 straight games in a week long period tournament. However, if we look at how much Japanese professional pitchers pitch and compare it to American pitchers, it may be a bit surprising. In Japanese professional baseball league, they play 144 games with 6 men rotation. A typical healthy starting pitcher will be pitching in about 24 games a season. Let's say he pitches 125 pitches a game, he would be throwing 3000 pitches a season. In comparison, in MLB, 162 games are played a season with 5 men rotation. A pitcher will be pitching in 32 -33 games on average with average of about 100 pitches per outing. He would end up throwing 3200-3300 pitches a season. More games played, more pitches thrown, less time to recover... this may be something we should be looking at when it comes to Japanese pitchers getting hurt after coming to play in MLB. Ohh and these pitch count numbers do not include pitches thrown in each bullpen session and side session between starts. 

Knee Balance Exercise

We all know that balance is an important factor for athletic performance and injury prevention. Balance exercises are done usually on a foot on the ground or uneven surface to make it harder. Or you can add a ball toss to make it more challenging. Also, you can do a balance exercise on your knee instead of your foot. It is hard to put your knee down on a hard surface so try doing it on a balance pad or BOSU ball, etc. It challenges more of your hip muscles and postural stability than regular balance exercise on a foot. Pictures below show the knee balance exercise. This is another way to train your hip and core stability and proprioception. Again, balance is an important factor when it comes to performance enhancement and injury prevention!

Left knee balance with his left foot and right leg in the air.

Knee balance with ball toss.

Core Stability and Respiration

Core stability is a crucial part of athletic performance and injury prevention during athletic activities. Importance of core muscles are well documented and known. However, less is known about how it may be affected by respiration. Abdominal muscles such as transverse abdominis and internal/external abdomini create the wall of the trunk, and the pelvic floor muscles create the bottom part of the core. The top part of it is the diaphragm. The diaphragm is also important in respiration. In fact, the abdominal muscles and diaphragm work in sync for respiration and core stability. In inhalation, the diaphragm contracts concentrically and the abdominal muscles contract eccentrically. In exhalation, they work in reverse. And the roles of these muscles get challenged with arm and leg movements and with respiration. It is known that a role of diaphragm in core stability decreases as it is challenged by increased demand for respiration. For example, during running, the diaphragm will work more for respiration and less for core stability than it does when at rest. What this may mean is that, during activities that increase respiration rate, the abdominal muscles may work non-optimally because they will have to help with respiration if the diaphragm cannot work optimally, leading to poor core stability. Performance of core muscles are also affected by other factors. Excessive lumbar extension will lengthen abdominal muscles putting them in non-optimal muscle length. Interestingly, the diaphragm also attaches to lumber spine from 1-3 level and excessive lumber spine extension may also affect performance of the diaphragm. Thus, it may be very important to take this into account when it comes to core stability.   

Pitch Velocity and Elbow Injury in Baseball

Shoulder and elbow injuries are very common in baseball players especially in pitchers. It is hard to watch baseball news on TV without hearing the word "Tommy John surgery" these days. Even before this Major League Baseball season starts, there are already quite a few pitchers that are going to miss this season from Tommy John surgery. Tommy John surgery is a reconstructive surgery for a torn ulnar collateral ligament in the elbow. We have discussed this and its rehabilitation in our previous posts. And it seems like a more popular topic in baseball news lately because of its frequency and names of the players involved in this. There is an interesting article published a few years ago done on high school baseball pitchers and it found out that there was a positive correlation between pitch velocity and stress placed on the elbow. The faster the pitch velocity was, the more stress placed on the medial side of the elbow where UCL is, according to this study. So does this mean that pitchers that throw faster pitches will be more prone to elbow injury such as UCL sprain?! We do not know. But this may be something that we cannot ignore....  

What is Meniscus Tear?!

Sports news world is busy with the news of the basketball player having a meniscus repair surgery. But what is meniscus?! Meniscus is a fibrocartilage that exists in the knee. Its roles are to absorb shocks and to make the knee joint more stable by deepening the concave part of the joint (tibia). There are 2 menisci in the knee; one located laterally and the other located medially. Medial meniscus is more commonly injured. Degenerative meniscus injury is common as people age. But it also happens in sports especially in sports that involve a lot of cutting, changing directions, and twisting such as soccer and basketball. It also happens with anterior cruciate ligament injury. Depending on where the injury is and how severe it is, it can be repaired. The center of meniscus does not have sufficient blood supply and does not heal well. The outside of it, on the other hand, is more vascularized and has more chance to heal. Meniscus repair seems to do better in younger athletes and in those who are having an ACL reconstructive surgery at the same time. Older knees have less chance of successful meniscus repair surgery. Athletes with meniscus tear may complain of dull aches and pain, sharp pain with motion, swelling, loss of motion, loss of function, joint line tenderness, etc. It may cause clicking sounds and it may feel like knee is locking up. The picture below is an arthroscopic view of torn meniscus. Whether a torn meniscus can be repaired depends on the location of the injury and the severity of it. Also, the age is a factor. If it is shaved off, it usually takes about 4 to 10 weeks to rehab. It is repaired it will take a lot longer. Rehabilitation of repaired meniscus usually involves non-weight bearing for 4-6 weeks and start partial weight-bearing and rehab may take as long as 4-6 months.

 



Lateral Posterior Hip Muscle Exercise for Baseball Pitchers

It is well known the importance of hip muscles, especially gluteal muscles and external rotators. They play an important role in not only stabilizing the hips but also the knees and lower legs. Every baseball pitcher has to be on one foot during stride phase of the pitching motion. If he is not able to maintain the stability of his lower leg, hip, and trunk, he will not be able to effectively transmit a ground reaction force through trunk, upper body, and to his arm and to the ball. Doing hip exercise on a table is a good way to start but he will need to train the muscles in standing as well. Here is one easy way to work on his hip muscle strength.

 

This is an isometric hip muscle (gluteal) strengthening exercise. He is pushing the physio ball into the wall with his left knee while trying to maintain his upright posture with his right leg. With this exercise, he should be able to maintain the upright posture without moving any part of the body. This works on his bilateral hip muscles, especially gluteus medius. If he brings his left knee up to the level of his hips, he now is working on his external rotators of his left hip as well as his right gluteus medius. Also he needs to use his core muscles to stabilize his pelvis.

Modified Sleeper Stretch

Major league baseball season is already half way through and summer baseball league is in a full swing for college and high school baseball players. We have already talked about how important it is to prevent injuries rather than treating injuries that have already happened. For baseball players especially pitchers, it is important to maintain sufficient shoulder range of motion(ROM) to prevent injuries. A loss of internal rotation and total arch of motion compared to the non-throwing arm of more than 5 degrees may put pitchers in increased risk of injury according to past studies. Several stretching techniques to increase or maintain shoulder internal rotation ROM have been described. One way to stretch is sleeper stretch. However, for high school and little league baseball level, there may not be a table available to lay on and do sleeper stretch. So, here is another way to do sleeper stretch. Instead of laying down on a table, a wall can be used to do the same stretching(pictures). Also, horizontal adduction(cross arm) stretching is an effective way to regain or maintain internal rotation motion. Stretching the shoulder on a daily basis especially after pitching is an important part of injury prevention for baseball pitchers.

Modified sleeper stretch (start)

Modified sleeper stretch (end)