Ankle sprains can occur through either sports or activities of daily living, and individuals can be at higher or lower risk depending on a variety of circumstances including their homeland, race, age, sex, or profession In addition, there are different types of ankle sprains such as eversion ankle sprains and inversion ankle sprains. Overall, the most common type of ankle sprain to occur is an inversion ankle sprain, where excessive plantar flexion and supination cause the anterior talofibular ligament to be affected. A study showed that for a population of Scandinavians, inversion ankle sprains accounted for 85% of all ankle sprains Most ankle sprains occur in more active people, such as athletes and regular exercisers.

Another study comparing gender influences on ankle sprains found that male and female counterparts had similar incidence rates of ankle sprains. However, at a specific age range of 19–25 years old, males were found to have a substantially greater rate of ankle sprains than females. Furthermore, at ages 30 and over, females showed a higher incidence of ankle sprains than males. From this, it can be said that age and activity levels are better indicators of ankle sprain risks than sex.

Risk factors for developing shin splints include:

- Excessive pronation at subtalar joint

- Excessively tight calf muscles (which can cause excessive pronation)

- Engaging the medial shin muscle in excessive amounts of eccentric muscle activity

- Undertaking high-impact exercises on hard, noncompliant surfaces (ex: running on asphalt or concrete)

- Smoking and low fitness level

While medial tibial stress syndrome is the most common form of shin splints, compartment syndrome and stress fractures are also common forms of shin splints. Females are 1.5 to 3.5 times more likely to progress to stress fractures from shin splints. This is due in part to females having a higher incidence of diminished bone density and osteoporosis.

The prevalence of Achilles tendinitis fluctuates greatly among different ages and groups of people. However, Achilles tendinitis is most commonly found in individuals aged 30–40. A study was conducted in 1981 on recreational and competitive runners and what type of injury they were most likely to suffer from. Out of the 232 runners, 25 (11%) complained that their Achilles bothered them.

A study conducted in the city of Oulu found that a peak incidence of 18 injured Achilles occurred in 1994 and was highest in the male group aged 30–39. The study also found that 90% of the injuries occurred while playing a sport.

Risk factors include participating in a sport or activity that involves running, jumping, bounding, and change of speed. Although Achilles tendinitis is mainly diagnosed in runners, it does occur in basketball, volleyball, dancing, gymnastics and other athletic activities. Other risk factors include gender, age, improper stretching, overuse, and conditions which the individual may be born with. Congenital conditions occur when an individual’s legs rotate abnormally, which in turn causes the lower extremities to overstretch and contract; this puts stress on the Achilles tendon and will eventually cause Achilles tendinitis.

Complications are likely to result in cases of excess blood loss or punctures to certain organs, possibly leading to shock. Swelling and bruising may result, more so in high-impact injuries. Pain in the affected areas may differ where severity of impact increases its likelihood and may radiate if symptoms are aggravated when one moves around.

Specific populations at high risk of primary PFPS include runners, bicyclists, basketball players, young athletes and females.

Several precautions may decrease the risk of getting a pelvic fracture. One study that examined the effectiveness of vitamin D supplementation found that oral vitamin D supplements reduced the risk of hip and nonvertebral fractures in older people. Certain types of equipment may help prevent pelvic fractures for the groups which are most at risk.

In 2010 national statistics was done by Agency for Healthcare Research and Quality for posterior cruciate ligaments injuries. They found that 463 patients were discharge for having some type of PCL injury. The 18- to 44-year-old age group was found to have the highest injuries reported (figure 1). One reason why this age group consists of the majority of injuries to the PCL is because people are still very active in sports at this age. Men were also reported having more injuries to the PCL (figure 3).

Running is a form of exercise and described as the one of the world's most accessible sport. However, its high-impact nature can lead to injury. Approximately 50% of runners are affected by some form of running injuries or running-related injuries (RRI) annually, and some estimates suggest an even higher frequency. The frequency of various RRI depend on the type of running, as runners vary significantly in factors such as speed and mileage. RRI can be both acute and chronic. Many of the common injuries that plague runners are chronic, developing over a longer period of time, as opposed to injury caused by sudden trauma, such as strains. These are often the result of overuse. Common overuse injuries include stress fractures, Achilles tendinitis, Iliotibial band syndrome, Patellofemoral pain (runners knee), and plantar fasciitis.

Proper running form is important in injury prevention. A major aspect of running form is foot strike pattern. The way in which the foot makes contact with the ground determines how the force of the impact is distributed throughout the body. Different types of modern running shoes are created to manipulate foot strike pattern in an effort to reduce the risk of injury. In recent years, barefoot running has increased in popularity in many western countries, because of claims that it reduces the risk of injury. However, this has not been proven and is still debated.

In terms of overuse injuries a British study found that:

- 40 percent occurred in the fingers

- 16 percent in the shoulders

- 12 percent in the elbows

- 5 percent were the knees

- 5 percent back

- 4 percent wrists

One injury that tend to be very common among climbers is Carpal tunnel syndrome. It is found in about 25% of climbers.

Isolated and combined posterolateral knee injuries are difficult to accurately diagnose in patients presenting with acute knee injuries. The incidence of isolated posterolateral corner injuries has been reported to be between 13% and 28%. Most PLC injuries accompany an ACL or PCL tear, and can contribute to ACL or PCL reconstruction graft failure if not recognized and treated. A study by LaPrade "et al." in 2007 showed the incidence of posterolateral knee injuries in patients presenting with acute knee injuries and hemarthrosis (blood in the knee joint) was 9.1%.

While the exact cause is unknown, shin splints can be attributed to the overloading of the lower leg due to biomechanical irregularities resulting in an increase in stress exerted on the tibia. A sudden increase in intensity or frequency in activity level fatigues muscles too quickly to properly help absorb shock, forcing the tibia to absorb most of that shock. This stress is associated with the onset of shin splints. Muscle imbalance, including weak core muscles, inflexibility and tightness of lower leg muscles, including the gastrocnemius, soleus, and plantar muscles (commonly the flexor digitorum longus) can increase the possibility of shin splints. The pain associated with shin splints is caused from a disruption of Sharpey's fibres that connect the medial soleus fascia through the periosteum of the tibia where it inserts into the bone. With repetitive stress, the impact forces eccentrically fatigue the soleus and create repeated tibial bending or bowing, contributing to shin splints. The impact is made worse by running uphill, downhill, on uneven terrain, or on hard surfaces. Improper footwear, including worn-out shoes, can also contribute to shin splints.

The meniscal tear is the most common knee injury. A meniscal tear tends to be more frequent in sports that have rough contact or pivoting sports such as soccer. The meniscal tear is more common in males than females. The ratio is about two and a half males to one female. Males between the ages of thirty-one and forty tend to tear their meniscus more frequently than younger men. Females on the other hand, seem to be more likely to tear their meniscus between the ages of eleven and twenty. People who work in straining jobs such as construction or pro athletes are also more likely to have a meniscal tear because of all the different tensions of their knees. According to the United States National Library of Medicine, the isolated medial meniscal tear occurs more frequently than any other tear associated with the meniscus. The prevalence of meniscus tears is the same for both knees. In a few different studies the BMI of a person can have a greater effect on the frequency of a meniscus tear because having a higher BMI will result in more weight on the joints which can cause the knee to be non-aligned which causes more weight on the muscles resulting in an easier tear. In 2008 the U.S Department of Health and Human Services reported a combined total of 2,295 discharges for the principal diagnosis of tear of lateral cartilage/meniscus (836.0), tear of medial cartilage/meniscus (836.1), and tear of cartilage/meniscus (836.2). Females had a total of 53.49% discharges while males had 45.72%. Individuals between the ages of 45–68 years had an average of 31.73% discharges followed by age group 65–84 with 28.82%. The average length of stay for a patient diagnosed with torn menisci was 2.7 days for males and 3.7 days for females. There was a report of 6,941 hospital discharges for knee repair. Individuals between 18–44 years of age were among the highest with 37.37% total of discharges followed by the age group 45–64 with a percentage of 36.34%. Males had a slightly higher number of discharges (50.78%) than females (48.66%). The average length of stay for both male and female patients in a hospital setting was 3.1.

604 injured rock climbers were prospectively evaluated from January 1998 to December 2001, due to the rapid growth of new complex finger trauma in the mid-1980s. Of the most frequent injuries, three out of four were related to the fingers: pulley injuries accounted for 20%, tendovaginitis for 7%, and joint capsular damage for 6.1%.

According to the posterior cruciate ligament injuries only account for 1.5 percent of all knee injuries (figure 2). If it is a single injury to the posterior cruciate ligament that requires surgery only accounted for 1.1 percent compared to all other cruciate surgeries but when there was multiple injuries to the knee the posterior cruciate ligament accounted for 1.2 percent of injuries.

Training of the feet, utilizing foot gymnastics and going barefoot on varying terrain, can facilitate the formation of arches during childhood, with a developed arch occurring for most by the age of four to six years. Ligament laxity is also among the factors known to be associated with flat feet. One medical study in India with a large sample size of children who had grown up wearing shoes and others going barefoot found that the longitudinal arches of the bare-footers were generally strongest and highest as a group, and that flat feet were less common in children who had grown up wearing sandals or slippers than among those who had worn closed-toe shoes. Focusing on the influence of footwear on the prevalence of pes planus, the cross-sectional study performed on children noted that wearing shoes throughout early childhood can be detrimental to the development of a normal or a high medial longitudinal arch. The vulnerability for flat foot among shoe-wearing children increases if the child has an associated ligament laxity condition. The results of the study suggest that children be encouraged to play barefooted on various surfaces of terrain and that slippers and sandals are less harmful compared to closed-toe shoes. It appeared that closed-toe shoes greatly inhibited the development of the arch of the foot more so than slippers or sandals. This conclusion may be a result of the notion that intrinsic muscle activity of the arch is required to prevent slippers and sandals from falling off the child’s foot.

In the US, the annual incidence of stress fractures in athletes and military recruits ranges from 5% to 30%, depending on the sport and other risk factors. Women and highly active individuals are also at a higher risk. The incidence probably also increases with age due to age-related reductions in bone mass density (BMD). Children may also be at risk because their bones have yet to reach full density and strength. The female athlete triad also can put women at risk as disordered eating and osteoporosis can cause the bones to be severely weakened.

Future research into posterolateral injuries will focus on both the treatment and diagnosis of these types of injuries to improve PLC injury outcomes. Studies are needed to correlate injury patterns and mechanisms with clinical measures of knee instability and laxity.

The cause of snapping hip syndrome is not well understood, and confusion exists within the medical community regarding causation. Athletes appear to be at an enhanced risk for snapping hip syndrome due to repetitive and physically demanding movements.

In athletes such as ballet dancers, gymnasts, horse riders, track and field athletes and soccer players, military training, or any vigorous exerciser, repeated hip flexion leads to injury. In excessive weightlifting or running, the cause is usually attributed to extreme thickening of the tendons in the hip region. Snapping hip syndrome most often occurs in people who are 15 to 40 years old.

A study containing 100 consecutive patients with a recent anterior cruciate ligament injury were examined with respect to type of sports activity that caused the injury. Of the 100 consecutive ACL injuries, there were also 53 medial collateral ligament injuries, 12 medial, 35 lateral and 11 bicompartmental meniscal lesions. 59/100 patients were injured during contact sports, 30/100 in downhill skiing and 11/100 in other recreational activities, traffic accidents or at work.

An associated medial collateral ligament tear was more common in skiing (22/30) than during contact sports (23/59), whereas a bicompartmental meniscal lesion was found more frequently in contact sports (9/59) than in skiing (0/30). Weightbearing was reported by 56/59 of the patients with contact sports injuries whereas 8/30 of those with skiing injuries. Non-weightbearing in the injury situation led to the same rate of MCL tears (18/28) as weightbearing (35/72) but significantly more intact menisci (19/28 vs 23/72). Thus, contact sports injuries were more often sustained during weightbearing, with a resultant joint compression of both femuro-tibial compartments as shown by the higher incidence of bicompartmental meniscal lesions. The classic "unhappy triad" was a rare finding (8/100) and Fridén T, Erlandsson T, Zätterström R, Lindstrand A, and Moritz U. suggest that this entity should be replaced by the "unhappy compression injury".

Development of tendinitis depends on the type, frequency and severity of exercise or use; for example, rock climbers tend to develop tendinitis in their fingers, swimmers in their shoulders. Achilles tendinitis is a common injury, particularly in sports that involve lunging and jumping. It is also a known side effect of fluoroquinolone antibiotics such as ciprofloxacin, as are other types of tendinitis.

Swelling in a region of micro-damage or partial tear can be detected visually or by touch. Increased water content and disorganized collagen matrix in tendon lesions may be detected by ultrasonography or magnetic resonance imaging.

Achilles tendinitis is thought to have physiological, mechanical, or extrinsic (i.e. footwear or training) causes. Physiologically, the Achilles tendon is subject to poor blood supply through the synovial sheaths that surround it. This lack of blood supply can lead to the degradation of collagen fibers and inflammation. Tightness in the calf muscles has also been known to be involved in the onset of Achilles tendinitis.

During the loading phase of the running and walking cycle, the ankle and foot naturally pronate and supinate by approximately 5 degrees. Excessive pronation of the foot (over 5 degrees) in the subtalar joint is a type of mechanical mechanism that can lead to tendinitis.

An overuse injury refers to repeated stress and strain, which is likely the case in endurance runners. Overuse can simply mean an increase in running, jumping or plyometric exercise intensity too soon. Another consideration would be the use of improper or worn-down footwear, which lack the necessary support to maintain the foot in the natural/normal pronation.

In general, overuse injuries are the result of repetitive impact between the foot and the ground. With improper running form, the force of the impact can be distributed abnormally throughout the feet and legs. Running form tends to worsen with fatigue. When moving at a constant pace, a symmetrical gait is considered to be normal. Asymmetry is considered to be a risk factor for injury. One study attempted to quantify the change in running form between a rested and fatigued state by measuring asymmetrical running gait in the lower limbs. The results showed that "knee internal rotation and knee stiffness became more asymmetrical with fatigue, increasing by 14% and 5.3%, respectively". These findings suggest that focusing on proper running form, particularly when fatigued, could reduce the risk of running related injuries. Running in worn out shoes may also increase the risk of injury and altering the footwear might be helpful. These injuries can also arise due to a sudden increase in the intensity or amount of exercise.

Bone mineral density decreases with increasing age. Osteoporotic bone loss can be prevented through an adequate intake of vitamin C and vitamin D, coupled with exercise and by being a non-smoker. A study by Cheng et al. in 1997, showed that greater bone density indicated less risk for fractures in the calcaneus.

ITBS can result from one or more of the following: training habits, anatomical abnormalities, or muscular imbalances:

Training habits

- Spending long periods of time/regularly sitting in lotus posture in yoga. Esp beginners forcing the feet onto the top of the thighs

- Consistently running on a horizontally banked surface (such as the shoulder of a road or an indoor track) on which the downhill leg is bent slightly inward, causing extreme stretching of the band against the femur

- Inadequate warm-up or cool-down

- Excessive up-hill and down-hill running

- Positioning the feet "toed-in" to an excessive angle when cycling

- Running up and down stairs

- Hiking long distances

- Rowing

- Breaststroke

- Treading water

Abnormalities in leg/feet anatomy

- High or low arches

- Supination of the foot

- Excessive lower-leg rotation due to over-pronation

- Excessive foot-strike force

- Uneven leg lengths

- Bowlegs or tightness about the iliotibial band.

Muscle imbalance

- Weak hip abductor muscles

- Weak/non-firing multifidus muscle

- Uneven left-right stretching of the band, which could be caused by habits such as sitting cross-legged

Extra-articular snapping hip syndrome is commonly associated with leg length difference (usually the long side is symptomatic), tightness in the iliotibial band (ITB) on the involved side, weakness in hip abductors and external rotators, poor lumbopelvic stability and abnormal foot mechanics (overpronation). Popping occurs when the thickened posterior aspect of the ITB or the anterior gluteus maximus rubs over the greater trochanter as the hip is extended.