Violent Sport

In case you needed a reminder of just how violent a sport football is, there was a terrible injury during the Vikings-Cardinals game last night. EJ Henderson of the Vikings fractured his femur when a teammate collided with him, resulting in a compressive and torsional force greater than the strength of his femur. Football players have gotten very strong and very fast, and the combination of these two variables leads to large forces during such collisions and often leads to injury. Hopefully he will be able to make a full recovery and return to action next season.

EJ Henderson Injury

Happy Thanksgiving!!

Just wanted to wish everybody a Happy Thanksgiving!! I hope everybody has a great holiday and I'll be back next week with a new post.

Who is Lisfranc? What is a Lisfranc injury?

An uncommon, but often misdiagnosed injury, is the Lisfranc fracture/dislocation. The Lisfranc joint, or tarsometatarsal articulation in the middle of the foot, is where the three cuneiform bones articulate with the first three metatarsals. This joint is named for Jacques Lisfranc, who was a general in Napoleon's army and performed an amputation through this joint of a soldier who fell, caught his foot in the stirrup, and developed gangreen. Lisfranc fractures account for fewer than 1% of all diagnosed fractures. It is often missed on the initial x-ray. In the everyday setting, this injury may result from a high energy car wreck or from falling from high places. In the sport of football, there have been a few prominent NFL players that have suffered this injury, including Dwight Freeny, Warrick Dunn, and this past Sunday, Ronnie Brown. If you watch the video of Brown's injury (link below), you will see that he planted his right foot, and then another player landed on his leg from behing, causing the injury. If a fracture occurs, surgery will most likely be performed, using screw fixation to repair the fracture. The rehabilitation from this injury is often lengthy, and may take up to a year.

Ronnie Brown injury

Why High Heels Are Bad!!

Instead of talking about sports injuries today, I thought I would get on my soapbox and discuss why high heels are bad. I'm not saying to absolutely never wear them, but everyday for 8 hours is not a good idea. When wearing high heels, a person must adjust their posture in order to accommodate the lift of the calcaneus. This adjustment occurs in the lower back (lumbar spine) and causes anterior rotation of the pelvis, which leads to back pain. Here are some facts about different heel heights:
1) a 1.9 cm heel increases forefoot pressure by 22%
2) a 5 cm heel increases forefoot pressure by 57%
3) an 8 cm heel increases forefoot pressure by 76%
In addition to causing low back pain and foot problems, high heels can also cause bunions if they are too narrow, nerve damage under the foot, and achilles tendon contractures. What the last part means is that by wearing high heels, it may chronically shorten the achilles tendon, which will lead to limited ankle motion, altered gait, and could possibly cause the achilles tendon to rupture. So, it is best to avoid high heels or limit their use to help avoid all these problems.

Head Up!!

This past weekend, an Auburn football player, Zac Etheridge, was involved in a serious injury during the Auburn-Ole Miss football game. While attempting to tackle Ole Miss running back Rodney Scott, Etheridge and teammate Antonio Coleman met head on in the above picture. It is never a good idea to attempt and tackle someone with your head down (neck flexion), because it lines up all the vertebrae in the neck and if the force is great enough, a domino effect will occur, fracturing the vertebrae and possibly leading to paralysis. After watching the video in class, one of my students pointed out that Etheridge likely wasn't trying to hit Scott with his head, but Coleman came into the play after he left his feet, and by then he couldn't change direction. After this collison, Etheridge lay motionless on the turf on top of Scott, and the Auburn medical staff did a great job stabilizing his cervical spine and placing him on the spineboard. As an athletic trainer, you always suspect a player has a spine injury when they get hit in the head. The most remarkable part of the play was Scott, who did not move until Etheridge was stabilized and moved off of him. The actions of Scott may have saved Etheridge from permanent paralysis, because any type of movement before he was stabilized could have caused a serious spinal cord injury. I am happy to report that Etheridge did not sustain any permanent damage, he has sprained ligaments in his neck and did fracture cervical vertebrae five. He will have to wear a neck brace for 3-4 months and is expected to make a full recovery. If you would like to see the video, click on the link below. It occurs around the 26 mintue mark of the video.

Zac Etheridge injury

Are you kidding me?

Watch this clip. BYU-New Mexico Soccer Fight


Today in motor development, we were discussing gender typing in sports. We were discussing how soccer is now viewed as both a male and female sport, and one of the students asked me if I saw the fight during the BYU-New Mexico match last night. I had not seen it, so recognizing a great opportunity for discussion, we viewed the video in class. You have to watch this for yourself. I don't know how one person could
1) do all these things to other players and 2) get away with it. You would think by the fifth incident one of the officials would have noticed. I'm not sure which was worse, pulling the girl down by her hair, kicking the ball into another player's face, or punching a player in the face. Just an unbelievable demonstration of how NOT to play the game.

Update

I found the video at http://www.secdigitalnetwork.com/default.aspx. It occurs on the very last play of the 3rd quarter. You should be able to move the video ahead to that play.

Patellar dislocations

I was originally going to do a post on why people should not wear high heels, but I was watching the Tennessee-South Carolina game this past weekend and saw an injury I just had to blog about. The patella is a seasmoid bone that lies in the trochlear groove between the medial and lateral femoral condyles. It moves up and down as we flex and extend our knee, and rarely comes out of place. A non-contact patellar dislocation may occur with a violent twisting motion of the leg, while a contact disclocation occurs when some outside force knocks it out of the groove. Three Tennessee defenders were trying to tackle a South Carolina player near the sideline, when one of the Tennessee players hit the patella of his teammate and knocked it out of the trochlear groove, resulting in a patellar dislocation. The patealla was located on the lateral femoral condyle, and clearly could be seen during the telecast. I've tried to locate the video of the injury, but have not had any luck yet. A physician will relocate the patealla back into place by flexing the hip, and gently pushing the patealla medially as the knee is extended. The athlete will likely miss four to six weeks or possibly longer after this injury. Like all other dislocations, once the patella is disclocated, it is much more likely to occur again.

AC Sprain

I apologize for the delay between blog posts. It's been a hectic couple of weeks. Keeping with the theme of discussing current football injuries, I thought it would be good to talk about AC sprains. The acromioclavicular joint is the articulation between the distal end of the clavicle and the acromion process of the scapula. It is a critical link in proper functioning of the shoulder complex. Anytime you move your shoulder, the clavicle moves with it. The common term for an AC sprain is a "seperated" shoulder, because of the seperation that occurs between the two bones. This can be a very painful and debiliating injury, especially for a quaterback. This injury commonly occurs from falling on an outstretched hand, or by landing direclty on the joint. In Sam Bradford's case, he landed directly on the AC joint during the BYU game, and again this past weekend against Texas. Because the AC joint is very superficial, it is not easy to protect with padding. It is even harder for a quarterback to rehabilitate from this injury because of the throwing motion. Depending on the severity of the injury, players can be out anywhere from a few days to a few months, if surgery is required to repair the ligaments.

Fun Fact: The Coracoacromial ligament actually connects to the same bone, the acromion process and coracoid process of the scaupula. Almost all ligaments connect two different bones together.
Fun Fact 2: One way to test for damage to the AC joint is to press down on the clavicle. If the clavicle "pops up" more than the non-injured side, then the person may have an AC sprain. This popping up of the clavicle is referred to as the "piano key" sign.

To play or not to play

Unless you live in a cave, you have probably seen the hits that lead to Tim Tebow suffering a concussion two weeks ago against Kentucky. Tebow actually took two hits to the head on the play, the one pictured to the right, and another to the back of the head when he hit the leg of his own lineman. Tebow was knocked unconscious and spent the night in a Kentucky hospital. The raging debate this week is whether or not Tebow should play against LSU Saturday night. Many times, commentators refer to a concussion as someone having "their bell rung." Well, that does not really describe what a concussion is, and the National Athletic Trainers Association (NATA) discourages the use of words such as "ding" and "bell rung". According to Arnheim and Prentice, a concussion, also know as a traumatic brain injury (TBI), is defined as "a clinical syndrome characterized by immediate and transient posttraumatic impairment of neural functions-such as alterations of consciousness, disturbance of vision, loss of equillibrium, etc., due to brain stem involvement." The majority of concussions do not involve loss of consciousness, but Tebow's did. Now, Tebow will undergo numerous tests to measure his cognitive function, equillibrium, physchological function, etc., to determine if he can play. These scores will be compared to baseline scores taken before the season started. If he passes all these tests and scans of his brain come back normal, he will likely be cleared to play. I do believe the medical staff at Florida will not clear him to play unless he passes all of these tests. The next question is, should he play, even if he is cleared? While there has been some good research done on concussions, the long term affects are still unknown. It will be a tough decision, and one I am glad I don't have to make.

Motor Milestones

We have been discussing recently different motor milestones and how infants progress through these milestones. For example, an infant must first be able to hold his or head up before they can crawl, and he or she must be able to stand without support before they can walk. There is an average age range that most infants reach these milestones by. We must remember, however, that these are just average ranges. I think sometimes we place too much emphasis on "Is my child normal?" We have to remember that these average ages are just that, averages. That means some children will reach these milestones faster and some slower than others. Does that mean there is something wrong with the child? Not necessarily. The average walking age is around 12 months. But, some children will begin walking as early as 9 months, and some will not walk until 15 months. The other thing to consider is that the individual constraints of the infant interact with the environment and task to influence how and when we move. So, an infant that has developed the appropriate muscular strength and is frequently placed in an environment that encourages her to walk will more than likely begin walking sooner than a child not placed in that environment.

"High" Ankle Sprains

We have been discussing the ankle in class, and one of the topics has been the "high" ankle sprain. The most common type of ankle sprain is the "lateral" ankle sprain, which damages the ligaments on the outside of the ankle that connect the talus to the fibula. Most of the time when people "roll" their ankle, they sustain a "lateral" ankle sprain. While not as common, the "high", or "syndesmosis" ankle sprain, can be much more debilitating. With a "high" ankle sprain, there is damage to the ligaments of the distal tibiofibular joint, primarily the anterior inferior and posterior inferior tibiofibular ligaments, and sometimes the interosseous membrane. To sustain a high ankle sprain, the talus, through hyperdorsiflexion, is forced up between the tibia and fibula, thus separating the bones from each other. This often occurs during a pile up in football when a player lands on the back of the leg of a lineman. Recovery for a high ankle sprain is often lengthy. Every time we walk or run, the talus is forced up into the distal tibiofibular joint. In a healthy person, this is not a problem, but in a person that has damaged these ligaments, it makes recovery difficult.

Rate limiters

I apologize for the length of time between posts. We have been discussing the concept of rate limiters recently in motor development. A rate limiter is an individual constraint, or system, that holds back of slows the emergence of a motor skill. One example would be a five year old trying to shoot a basketball on a ten foot goal. He or she will lack the muscular strength to shoot the ball at a goal this high. Therefore, the muscular system would be the rate limiter. We had a really good discussion in class about how a single rate limiter of one system can affect numerous systems. As we age, certain parts of our body begin to break down. A common problem is arthritis. As people develop arthritis, which affects the joints, they tend to decrease their amount of physical activity. Well, a lack of physical activity leads to a loss of bone mass, muscle mass, degeneration of the nervous system, and many other health problems. So, what starts off as one problem eventually leads to the development of several problems. It is important to determine what rate limiter may be holding a person back and attempt to correct it before more problems arise.

Uralacher's Wrist Injury

If you follow the NFL, then you know that the Bears All Pro linebacker, Brian Urlacher, dislocated his "wrist" Sunday night against the Packers and will be out the remainder of the season after undergoing surgery yesterday. The term "wrist" only describes a general area of the body, and the exact bone that was dislocated was not disclosed in any of the press releases. The actual "wrist" is the articulation of the distal end of the radius with the proximal row of carpal bones (four bones). The most commonly dislocated carpal bone is the lunate, which is located almost directly beneath the middle finger. This bone helps hold the wrist together, and often times when it is dislocated, it must be put back into place with pins via surgery. This type of surgery requires a lengthy recovery. I was able to do some digging and Urlacher did, in fact, dislocate the lunate.

MCL "Sprain"

I blogged a couple of weeks ago about the difference between a "sprain" and a "strain." Well, during the Steelers-Titans game last night, there was a great example of a MCL sprain. The Medial Collateral Ligament is the ligament on the inside of the knee. It helps prevent the knee from "buckling" on the inside. It is frequently injured in football and injured much more frequently than the Lateral Collateral Ligament. Typically, the ligament is damaged by a valgus force, which is a force directed in the lateral to medial direction. In the above picture, the Titans player landed on the lateral aspect of the knee of Troy Polamalu, which stretched and damaged the MCL on the medial side. Football players are hit much more frequently on the lateral or outside of the knee, which causes damage to the MCL. Polamalu is reported to be out for 3-6 weeks, which would lead me to believe it is a Grade II MCL sprain. If the ligament was completely torn, as in the top picture, he would probably be out much longer, if not the entire season. With a grade II sprain, there is some tearing of the ligament, but not a complete disruption. He will likely wear a knee brace when he returns to help protect against a repeat of this injury.

Exercise is Medicine Part II

I blogged a couple of weeks ago about the "Exercise is Medicine" campaign and how the president of ACSM was coming to Mississippi State to help promote the campaign. Well, that day was today. There was a great turnout in front of the student union at the press conference and a standing room only crowd at question and answer session, which featured our own department head, Dr. Brown. Many students came out to support the event, and hopefully more people in the community, state, and nation will become more active. As professionals in the field of Health, I feel we have to set an example for others on the importance of physcial activity, and the best way to do this is to be active ourselves. It would be difficult for anyone in the field of health, kinesiolgy, etc., to stress the importance of exercise if they don't exercise themselves. Every journey begins with a "step", and hopefully this campaign will encourage more people to exercise. Check out the link below for more information on the program. I'll be back Friday with another football injury blog for the weekend.
http://www.exerciseismedicine.org/public.htm

Did he really fully "extend" to catch the ball?

Since this is the opening weekend of college football, we will stick with that theme. Over the course of the season, you'll undoubtedly see many diving catches like the one above. Often times, the announcer will say that the player "fully extended" to catch the pass. Well, this just isn't true. We have been discussing joint actions in class this past week, and I'm sure all of my students could tell you why this isn't true. First, we must identify the joint where the action is taking place. To say a player "fully extended" really does not give an indication of what happened. We must specify the joint where this action, such as flexion, extension, abduction, etc., is taking place. After identifying the joint, we must then identify the proper joint action. I believe that when announcers say a player "fully extended", they are referring to the shoulder/arm. Well, in the above picture, and almost all cases where a player dives for a ball, the motion at the shoulder is not extension, but flexion. The definition of flexion is a motion that decreases the angle of a joint, or moves the segment into the fetal position. In the above picture, it is clear that the athlete's shoulders are moving into the fetal position, therefore, he has shoulder flexion. He also has elbow flexion, wrist flexion, and knee flexion, making the "fully extended" statement even more incorrect. So the next time you are watching a game or Sportscenter and see a diving catch, pay close attention to the description of the movement. It just might not be accurate.

Is it a sprain or a strain?

With the start of football season right around the corner, many injuries are sure to follow. Two terms that are commonly used incorrectly by broadcasters and the media are "sprain" and "strain." These terms are often used interchangeably, but are not the same thing. When an athlete has a ligamentous injury, this is referred to as a "sprain". A "sprain" would indicate stretching or tearing of a ligament. Probably the most commonly sprained ligament among football players would be the medical collateral ligament (MCL) of the knee. When an athlete has a muscle or tendon injury, this is referred to as a "strain", which would indicate tearing or stretching of the muscle/tendon. The most common muscle strain would be the hamstrings, which is a group of three muscles located on the posterior aspect of the thigh. I'll focus on the reason why the hamstrings are so commonly strained in a later blog. So, when your watching football over the next few months, and the announcer states a player is out with a strained MCL, you will know he/she is incorrect!

Exercise is Medicine

On September 9, Mississippi State University will be hosting the president of the American College of Sports Medicine (ASCM) to promote the "Exercise is Medicine" Campaign. The day will feature speeches by the president of MSU, the mayor of Starkville, the president of ACSM, and a question and answer session featuring various health care professionals. The purpose of "Exercise is Medicine" is to encourage physicians to prescribe exercise in much the same way they would prescribe medication, and to encourage people to exercise. The benefits of exercise are numerous, too many for me to list here (Here are a few: http://www.webmd.com/fitness-exercise/benefits-of-exercise). In this country, there is a "large" problem with inactivity and obesity. There is no possible way to obtain all the benefits exercise provides by taking a pill. For many, the most difficult part of exercising is getting started. It doesn't take much, just 30 minutes of walking 4-5 days/wk will yield benefits. For more information on this program, you can visit the following websites:
http://www.exerciseismedicine.org/
http://www.health.msstate.edu/health/eim.htm

Both classes went well today. In anatomical kinesiology, we continued discussion on muscles, and talked about the length/tension relationship for a sarcomere and whole muscle. Motor Development focused on continuing to explore the theoretical backgrounds of developement.
I hope everyone has a good weekend. I'll be back Monday with a blog on muscular injuries.

8-26-09

Anatomical Kinesiology: Today we began discussing the muscular system and how skeletal muscles produce voluntary movement. Skeletal muscle and the tendons associated with it (musculotendinous unit) can be represented by Hill's muscle model. The contractile component (CC) contains the contractile proteins found in the myofibril, actin and myosin. These proteins produce active tension. The parallel elastic component (PEC) runs parallel to the contractile component and is compromised of the connective tissues surrounding the muscle (epimysium, perimysium, and endomysium). The series elastic component (SEC) is represented by the tendons and all other connective tissue in series with the contractile component. The PEC and SEC, because of their elastic properties, produce passive tension. This will be discussed in further detail on Friday.

Motor Development: Today we discussed the three major theoretical perspectives of Motor Development. The earliest perspective, the maturational perspective, argues that development is driven by genetics and an internal biological clock. It does not consider the role of the environment and considers the nervous system to be the only system responsible for development. The second theory is the information processing theory. This theory considers the brain as functioning much like a computer. The third and most recent perspective is the ecological perspective. This includes both the dynamical systems and perception-action theories. The ecological perspective considers all internal systems (skeletal, muscular, nervous, etc.), and the interaction of these systems with the environment and task as shaping development and movement. Friday's class will focus on exploring these perspectives further.

Summary From 8-24-2009

Antatomical Kinesiology: Today we finished discussing different types of bones and their function. Most bones are named for their shape and indicate their function. For example, flat bones, such as the bones of the cranium, are designed for protection. We also discussed the six different types of loading and examples of fractures caused by these different types of loading. Three point bending is my favorite type of loading, this occurs when the bone is subjected to three forces, creating tension on one side of the bone and compression on the opposite side. The classic example of three point bending is the boot top fracture. We will have a quiz on Wednesday on anatomical terminlogy as well as the skeletal system.

Motor Development: Today we finished up the first chapter on the introduction to Motor Development. While the fields of Motor Development, Motor Learning, and Motor Control are related, it is also important to understand and recognize the differences. We have also spent a lot of time discussing contstraints and how they work together to shape movement. Using Newell's model, we can identify the individual, environmental, and task constraints that all work together to influence how we move. Wednesday we will begin discussing the different theories of motor development.

Kinesiology Blog

This blog is intended to give insights into the world of Kinesiology. I'll be posting summaries from class meetings as well as updates on research and other events in the field of Kinesiology. If you are one of my students, feel free to comment on the blog and post comments or ask questions. I will do my best to answer them as quickly as possible. If you are a potential student or just a person curious about the field of Kinesiology, also feel free to post comments or questions. This blog is intended to enhance the discussion of classroom materials as well as introduce people to Kinesiology. For those not familiar with Kinesiology, it is the study of movement. I am an assistant professor in the Department of Kinesiology here at Mississippi State University. Feel free to check out our webpage; the link is on the righthand side of this page. We have a very diverse faculty with many different interests, including exercise physiology, exercise psychology, pedagogy, coaching, sports administration, and others areas. My background is in Biomechanics, and much of my research is focused on understanding the mechanics of injuries, such as ankle sprains.