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.

Women in sports such as association football, basketball, and tennis are significantly more prone to ACL injuries than men. The discrepancy has been attributed to gender differences in anatomy, general muscular strength, reaction time of muscle contraction and coordination, and training techniques.

Gender differences in ACL injury rates become evident when specific sports are compared. A review of NCAA data has found relative rates of injury per 1000 athlete exposures as follows:

- Men's basketball 0.07, women's basketball 0.23

- Men's lacrosse 0.12, women's lacrosse 0.17

- Men's football 0.09, women's football 0.28

The highest rate of ACL injury in women occurred in gymnastics, with a rate of injury per 1000 athlete exposures of 0.33

Of the four sports with the highest ACL injury rates, three were women's – gymnastics, basketball and soccer.

According to recent studies, female athletes are two to eight times more likely to strain their anterior cruciate ligament (ACL) in sports that involve cutting and jumping as compared to men who play the same particular sports (soccer, basketball, and volleyball). Differences between males and females identified as potential causes are the active muscular protection of the knee joint, the greater Q angle putting more medial torque on the knee joint, relative ligament laxity caused by differences in hormonal activity from estrogen and relaxin, intercondylar notch dimensions, and muscular strength.

Knee injuries are very common among athletes as well as regular active people and can always be prevented. Ligament tears account for more than forty percent of knee injuries and the posterior cruciate ligament is considered one of the less common injuries. Although it is less common, there are still important measures that can be taken in order to prevent this type of knee injury. Maintaining proper exercise and sport technique is crucial for injury prevention, which include not exceeding the body or not going over the proper range of motion of the knee, properly warming up and cooling down

High school athletes are at increased risk for ACL tears when compared to non-athletes. This risk increases with certain types of sports. Among high school girls, the sport with the highest risk of ACL tear is soccer, followed by basketball and lacrosse. The highest risk sport for boys was basketball, followed by lacrosse and soccer. Children and young athletes may benefit from early surgical reconstruction after ACL injury. Young athletes who have early surgical reconstruction of their torn ACL are more likely to return to their previous level of athletic ability when compared to those who underwent delayed surgery or nonoperative treatment. They are also less likely to experience instability in their knee if they undergo early surgery.

Tear of a meniscus is a common injury in many sports. The menisci hold 30–50% of the body load in standing position. Some sports where a meniscus tear is common are American football, association football, ice hockey and tennis. Regardless of what the activity is, it is important to take the correct precautions to prevent a meniscus tear from happening.

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".

In the original description by Hume, where the olecranon fractures were not displaced, treatment consisted of closed reduction of the radial head dislocation under general anaesthesia by supination of the forearm. This was followed by immobilisation of the arm in a plaster cast with the elbow flexed at 90° and the forearm in supination for 6 weeks.

Where the olecranon fracture is displaced, open reduction internal fixation is recommended. Once the olecranon has been repaired, closed reduction of the radial head dislocation is usually possible. This is followed by immobilisation with the elbow flexed to 90° and the forearm in the neutral position. The duration of immobilisation depends on clinical assessment of the joint, and mobilisation may be possible after as little as 4 weeks.

There are three major ways of preventing a meniscus tear. The first of these is wearing the correct footwear for the sport and surface that the activity is taking place on. This means that if the sport being played is association football, cleats are an important item in reducing the risk of a meniscus tear. The proper footwear is imperative when engaging in physical activity because one off-balanced step could mean a meniscus tear.

It is highly advised that cleats contain a sole that molds around the foot, no less than fourteen cleats per shoe, no lower than a half inch diameter of the cleat tip, and at most, a three-eighths inch of cleat length.

Future research with regard to medial knee injuries should evaluate clinical outcomes between different reconstruction techniques. Determining the advantages and disadvantages of these techniques would also be beneficial for optimizing treatment.

As with any body part, maintaining strength and flexibility of the muscles can help to prevent injuries. Specifically in the knee, the quadriceps and hamstring muscles help to stabilize the knee, and maintaining their strength and flexibility will help prevent minor stresses from developing into major injuries. Proper footwear can also help prevent injuries. Wearing shoes that are appropriate for the activity help decrease the risk of slipping or twisting forces acting on the knee. In some circumstances, prophylactic bracing or taping may reduce the risk of injury as well.

Treatment of medial knee injuries varies depending on location and classification of the injuries. The consensus of many studies is that isolated grade I, II, and III injuries are usually well suited to non-operative treatment protocols. Acute grade III injuries with concomitant multiligament injuries or knee dislocation involving medial side injury should undergo surgical treatment. Chronic grade III injuries should also undergo surgical treatment if the patient is experiencing rotational instability or side-to-side instability.

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 injury can be debilitating for athletes of many sports who need to accelerate, quickly change direction, or jump. Use of the toes is not possible during the healing process. Since the toes are necessary for proper push-off when accelerating, those sorts of athletic activities should be almost completely curtailed. An extended healing period of one or more months is often required.

Because of the anatomy of the distal foot and the unique use of the foot, it is often impossible to properly tape or brace the joint. Although difficult, it is not impossible to tape the toe to limit extension (upward bend of toe). Additionally, wearing a shoe with a rigid sole (often a metal plate) and cushioned innersole will help minimize extension of the joint. Anti-inflammatory medication as well as physical therapy is recommended.

Turf toe is usually healed in about 2–3 weeks. It can become more serious if left untreated, and may cause serious problems for the athlete. Treating the injury includes icing of the area, elevating the foot, or possibly the use of custom orthotics.

The first-line treatment for a muscular strain in the acute phase include five steps commonly known as P.R.I.C.E.

- Protection: Apply soft padding to minimize impact with objects.

- Rest: Rest is necessary to accelerate healing and reduce the potential for re-injury.

- Ice: Apply ice to induce vasoconstriction, which will reduce blood flow to the site of injury. Never ice for more than 20 minutes at a time.

- Compression: Wrap the strained area with a soft-wrapped bandage to reduce further diapedesis and promote lymphatic drainage.

- Elevation: Keep the strained area as close to the level of the heart as is possible in order to promote venous blood return to the systemic circulation.

Immediate treatment is usually an adjunctive therapy of NSAID's and Cold compression therapy. Controlling the inflammation is critical to the healing process. Cold compression therapy acts to reduce swelling and pain by reducing leukocyte extravasation into the injured area. NSAID's such as Ibuprofen/paracetamol work to reduce the immediate inflammation by inhibiting Cox-1 & Cox-2 enzymes, which are the enzymes responsible for converting arachidonic acid into prostaglandin. However, NSAIDs, including aspirin and ibuprofen, affect platelet function (this is why they are known as "blood thinners") and should not be taken during the period when tissue is bleeding because they will tend to increase blood flow, inhibit clotting, and thereby increase bleeding and swelling. After the bleeding has stopped, NSAIDs can be used with some effectiveness to reduce inflammation and pain.

A new treatment for acute strains is the use of platelet rich plasma (PRP) injections which have been shown to accelerate recovery from non surgical muscular injuries.

It is recommended that the person injured should consult a medical provider if the injury is accompanied by severe pain, if the limb cannot be used, or if there is noticeable tenderness over an isolated spot. These can be signs of a broken or fractured bone, a sprain, or a complete muscle tear.

In 1936, Cambell stated that an "impairment of the anterior crucial and medial ligaments is associated with injuries of the internal cartilage". In 1950, O'Donoghue described the unhappy triad as: (1) rupture of the medial collateral ligament, (2) damage to the medial meniscus and (3) rupture of the anterior cruciate ligament. O'Donoghue estimated the incidence rate in the traumatic sports knee to be 25%.

In 1991, Shelbourne and Nitz questioned the validity of O'Donoghue's terrible triad study. A review of all arthroscopically confirmed acute injuries of second degree or worse to the ACL and MCL was performed. Of the 52 knees reviewed, 80% of group 1 had lateral meniscus tears and 29% had associated medial meniscus tears. None of the medial meniscus tears were isolated; medial meniscus tears were not present in the absence of a lateral meniscus tear. From this study, it was concluded that the structures more typically involved in a triad were the anterior cruciate ligament, medial collateral ligament, and the lateral (not medial) meniscus.

If the femur head is dislocated, it should be reduced as soon as possible, to prevent damage to its blood supply. This is preferably done under anaesthesia, following which, leg is kept pulled by applying traction to prevent joint from dislocating.

The final management depends on the size of the fragment(s), stability and congruence of the joint. In some cases traction for six to eight weeks may be the only treatment required; however, surgical fixation using screw(s) and plate(s) may be required if the injury is more complex. The latter treatment will be called for if bone fragments do not fall into place, or if they are found in the joint, or if the joint itself is unstable.

Although the precise mechanism of injury is unclear, the injury occurs in children who have fallen heavily with their arm trapped under the body. In his original description of the injury, Hume suggested that the injury occurred as a result of hyperextension of the elbow leading to fracture of the olecranon, with pronation of the forearm leading to the radial head dislocation.

Although strains are not restricted to athletes and can happen while doing everyday tasks, however, people who play sports are more at risk for developing a strain. It should also be noted that it is common for an injury to develop when there is a sudden increase in duration, intensity, or frequency of an activity.

Depending on the stability achieved via initial treatment, the patient may be allowed to stand and walk with help of support within about six to eight weeks. Full function may return in about three months.

Options include operative or non-operative treatment. If the dislocation is less than 2 mm, the fracture can be managed with casting for six weeks. The patient's injured limb cannot bear weight during this period. For severe Lisfranc injuries, open reduction with internal fixation (ORIF) and temporary screw or Kirschner wire (K-wire) fixation is the treatment of choice. The foot cannot be allowed to bear weight for a minimum of six weeks. Partial weight-bearing may then begin, with full weight bearing after an additional several weeks, depending on the specific injury. K-wires are typically removed after six weeks, before weight bearing, while screws are often removed after 12 weeks.

When a Lisfranc injury is characterized by significant displacement of the tarsometatarsal joint(s), nonoperative treatment often leads to severe loss of function and long-term disability secondary to chronic pain and sometimes to a planovalgus deformity. In cases with severe pain, loss of function, or progressive deformity that has failed to respond to nonoperative treatment, mid-tarsal and tarsometatarsal arthrodesis (operative fusion of the bones) may be indicated.

This method should be used within the first 48–72 hours after the injury in order to speed up the recovery process.

Heat: Applying heat to the injured area can cause blood flow and swelling to increase.

Alcohol: Alcohol can inhibit your ability to feel if your injury is becoming more aggravated, as well as increase blood flow and swelling.

Re-injury: Avoid any activities that could aggravate the injury and cause further damage.

Massage: Massaging an injured area can promote blood flow and swelling, and ultimately do more damage if done too early.

The radial head fracture is usually managed by open reduction internal fixation; if the fracture is too comminuted, a radial head implant can be used. Excision of the radial head should be avoided, as the radius will migrate proximally leading to wrist pain and loss of pronation and supination of the wrist. Delayed treatment of the radial head fracture will also lead to proximal migration of the radius.

The distal radio-ulnar joint dislocation can be reduced by supination of the forearm, and may be pinned in place for 6 weeks to allow healing of the interosseous membrane.

Turf toe is named from the injury being associated with playing sports on rigid surfaces such as artificial turf and is a fairly common injury among professional American football players. Often, the injury occurs when someone or something falls on the back of the calf while that leg's knee and tips of the toes are touching the ground. The toe is hyperextended and thus the joint is injured. Additionally, athletic shoes with very flexible soles combined with cleats that "grab" the turf will cause overextension of the big toe. This can occur on the lesser toes as well. It has also been observed in sports beyond American football, including soccer, basketball, rugby, volleyball, and tae kwon do. This is a primary reason why many athletes prefer natural grass to turf, because it is softer.

In humans, the midfoot consists of five bones that form the arches of the foot (the cuboid, navicular, and three cuneiform bones) and their articulations with the bases of the five metatarsal bones. Lisfranc injuries are caused when excessive kinetic energy is applied either directly or indirectly to the midfoot and are often seen in traffic collisions or industrial accidents.

Direct Lisfranc injuries are usually caused by a crush injury, such as a heavy object falling onto the midfoot, or the foot being run over by a car or truck, or someone landing on the foot after a fall from a significant height. Indirect Lisfranc injuries are caused by a sudden rotational force on a plantar flexed (downward pointing) forefoot. Examples of this type of trauma include a rider falling from a horse but the foot remaining trapped in the stirrup, or a person falling forward after stepping into a storm drain.

In athletic trauma, Lisfranc injuries occur commonly in activities such as windsurfing, kitesurfing, wakeboarding, or snowboarding (where appliance bindings pass directly over the metatarsals). American football players occasionally acquire this injury, and it most often occurs when the athlete's foot is plantar flexed and another player lands on the heel. This can also be seen in pivoting athletic positions such as a baseball catcher or a ballerina spinning.

The RICE method is an effective procedure used in the initial treatment of a soft tissue injury.

Rest: It is suggested that you take a break from the activity that caused the injury in order to give the injury time to heal.

Ice: The injury should be iced on and off in 20 minute intervals, avoiding direct contact of the ice with the skin.

Compression: Bandaging the injury will compress it, and prevent any further bleeding or swelling from occurring.

Elevation: Elevating the injury above the heart while resting will aid in the reduction of swelling.