Take a look at one of your limbs and straighten it as much as you can. Notice that your elbows and knees each have a clearly defined limit of rotation – these are called “joint limits”. While you might not think about them much, Brazilian Jiu Jitsu fighters see our joint limits as exploitable weaknesses. Martial artists have been inventing and refining ways to hyperextend their opponents’ joints for hundreds (if not thousands) of years. These “joint submissions” are executed by acting as human levers or torque wrenches, trying to rotate joints past their limits.
Continue reading “Tap out before your ligaments do: The mechanics of Jiu Jitsu joint submissions”Tag: joints
Where the Treatable can become Life-Threatening: The Link Between Patellar Dislocations, Biomechanics, and Wilderness Emergency Medicine
The dislocation of the patella is the dislocation of the kneecap sideways— either laterally, to the outward facing side of the leg, or medially, to the inward facing side of the leg. While the condition is rare, accounting for around 3% of knee injuries, acute patellar dislocations are painful health emergencies with long-lasting consequences if not properly treated. This is especially true in a wilderness medicine context: a patellar dislocation may create dangerous and even deadly scenarios in the backcountry, where long, complicated evacuation processes will prolong patient discomfort and the precarious wilderness environment may lead to further danger. Thus certified wilderness first responders are permitted to perform straightforward dislocation reductions in a backcountry setting to alleviate pain and assist evacuation.
Continue reading “Where the Treatable can become Life-Threatening: The Link Between Patellar Dislocations, Biomechanics, and Wilderness Emergency Medicine”Patellar Tendonitis: Affecting Forces and Recovery Methods
Patellar tendonitis, also known as jumper’s knee, is inflammation of the patellar tendon. This tendon connects the patella (kneecap) to the tibia. Its function is to extend the leg by transmitting the force produced by the quad to do so. Tendonitis develops when there is overuse of the tendon, Athletes who participate in sports such as basketball or volleyball are more likely to develop patellar tendonitis. Tendonitis is a complex injury that is difficult to overcome and can delay an athlete’s return to play. Understanding the forces acting on the tendon during jumping can help create a plan that will help the athlete return to play quickly and reduce the chances of reinjury.
Continue reading “Patellar Tendonitis: Affecting Forces and Recovery Methods”Ostrich-ized From Flight, But Not From Stride: The Unique Biomechanics of the World’s Fastest Bird
Ostriches are the largest two-footed bird. While they are unable to fly, they are the fastest running birds in the world, reaching speeds of up to 43 mph. But how are these large birds able to reach such fast speeds? Understanding the kinematics of ostrich motion compared to humans can reveal to us important information that can help when designing human-based technologies.
Continue reading “Ostrich-ized From Flight, But Not From Stride: The Unique Biomechanics of the World’s Fastest Bird”Double-Jointedness: the Benefits and Drawbacks of Hypermobility
Simone Biles, Michael Phelps, Patrick Mahomes, and Shohei Ohtani are all athletes who have benefited from hypermobile joints. However, hypermobility can be both a blessing and a curse. Joint hypermobility, or “double-jointedness”, is when joints are able to move beyond their normal range of motion, and the connective tissue holding joints together is loose or weak. Most people with hypermobile joints do not experience any issues, but some suffer from ligament and tendon injuries, joint pain, tiredness, anxiety disorders, and bowel issues.
Continue reading “Double-Jointedness: the Benefits and Drawbacks of Hypermobility”Silly Name, Serious injury. How Tension on the Metatarsal Joint Leads to Common Sports Injury “Turf Toe.”
In some of the world’s greatest sports such as football, soccer, basketball, etc., injuries are the topic of conversation. How many weeks will the franchise athlete miss with an Achilles tear, knee sprain, Tommy John surgery, or broken bone? However, an injury to the metatarsophalangeal joint, commonly known as Turf Toe, can cause an athlete severe pain leaving star players sidelined for prolonged periods of time. While the increased flexion at the connection between the great or big toe and the bottom of the foot will continue to be present in every high-level sport, understanding the mechanics surrounding this injury might help remediate and treat this pain in the future.
Continue reading “Silly Name, Serious injury. How Tension on the Metatarsal Joint Leads to Common Sports Injury “Turf Toe.””It’s Not About How Well You Fall, but How Well You Land – The Biomechanics of a Military Parachute Landing
Airborne operations have been a tactically advantageous method of entering a battlefield for decades. However, falling and more importantly, landing require a very technical and precise skill set to execute correctly without providing harm to the soldier’s body. The rapid deceleration that results when a paratrooper lands places a lot of force in a short amount of time on their joints. The rate of injury in airborne jumps is about 5 out of every 1000. An understanding of what is going on when a paratrooper lands— both correctly and incorrectly— can be beneficial to helping reduce injury to the soldier, and preserve the longevity of the soldier’s body.
Continue reading “It’s Not About How Well You Fall, but How Well You Land – The Biomechanics of a Military Parachute Landing”Taking Collagen and Copper Supplements can decrease the risk of bone fractures
When we think of building strong bones, most of us picture drinking plenty of milk for its calcium—at least, that’s what our elementary gym teachers used to tell us. But building and maintaining strong bones requires more than just calcium from milk; supplemental vitamins play a key role in the development and maintenance of strong bones. Bone fractures are common in young, but especially elderly people, and adding collagen supplements to one’s diet can have a major impact on bone toughness reducing the risk of fractures.
Continue reading “Taking Collagen and Copper Supplements can decrease the risk of bone fractures”From Strain to Pain: Role of Altered Loadings at Joints as Onset for Osteoarthritis (OA)
Featured image courtesy of InjuryMap.
Joint degenerative diseases, such as Osteoarthritis, are an increasing cause of pain and disability in millions of people worldwide, per Sanchez-Adams et. al. As a culture of intense, nonstop work is promoted, people incline to not give their bodies enough time to rest, which has increased the cases of joint injuries, especially those to the lower body; specifically in those populations that are exposed to high intensity physical activity. This is concerning, since it has been discovered that joint injuries provoke an alteration in how these joints distribute loads, drifting from their physiological, or typical/natural, behavior, as demonstrated by Ko et. al. Consequently, this affects the biological response of the bone and cartilage that compose that affected joint, leading to potential degeneration due to the altered mechanotransduction (interpretation of mechanical signals to biochemical ones) interactions of the cell and cartilage forming cells, osteocytes and chondrocytes. This degeneration is what characterizes the concerning and debilitating Osteoarthritis (OA). This leads us to our questions: Why does the altered loading affect my joints? If I suffer an injury, can I prevent the degeneration of my joints and live a long, healthy life?
Continue ReadingYour ankle could replace your knee! – How Rotationplasty gives ankles new function.
Typically, the joys of childhood that adults reminisce about include carefree playing, running, and jumping—not cancer. Despite this, childhood cancer affects nearly 10,000 children in the U.S. every year, and of these cases, about 500 (2 percent) involve osteosarcoma. Rotationplasty is a surgery that can give childhood osteosarcoma survivors requiring amputation the best chance of running and jumping again, just like before.
Read more: Your ankle could replace your knee! – How Rotationplasty gives ankles new function. Continue reading “Your ankle could replace your knee! – How Rotationplasty gives ankles new function.”