There are two main types of knee joint injury; acute and chronic. Acute injuries occur in an instant (e.g. bone fracture) and chronic injuries (e.g. stress fractures and tendinitis) occur over a period of time and are usually classified as overuse injuries. Here I am mainly addressing acute injuries. They may vary in severity from mild to moderate and severe. Sprains (an injury to ligaments that connect bone to bone) and strains (an injury to tendons that connect bone to muscle) may also be classified as first degree (least severe with mild stretching) to second degree and third degree (most severe with complete rupture). Hence, for example, the expression knee strain is often used when in fact it is a knee sprain because it really involves ligament damage.
The knee is stabilised and supported by four main ligaments. The medial collateral ligament (mcl) spans the medial side (inside) of each knee and prevents the knee joint opening up when a force is applied to the outside of the knee (e.g. due to a football tackle). At the centre of the knee joint are two ligaments that form a cross or cruciate ligament arrangement. One is called the posterior cruciate ligament (pcl) and the other the anterior cruciate ligament (acl). The pcl holds the knee together from the back and the acl stabilises the knee from the front. Acl knee injury is very common in high impact sports involving lots of direction changes where a foot may be instantaneously planted on the floor and the knee strongly rotated or hit (e.g. basketball, football, rugby). There is always a large demand for acl rehab and mcl recovery because of how common these injuries are in sports.
The menisci (medial and lateral) rest on the ends of the main lower leg bones (Tibia) and provide C shaped energy absorbing cushions between the upper leg bones (Femurs) and Tibias to reduce contact friction and evenly distribute impact loads. Meniscal tears may be caused by forceful twisting of the knee (e.g. netball), are often associated with ligament sprains and cause rough edges on the previously smoothly sliding surfaces.
There are many other forms of other knee injuries as well, including Bursitis (inflammation of one of the fourteen fluid filled sacks in the knee area due to for example, repetitive jumping and improper gait), Osteochondritis Dissecans (loose cartilage becomes trapped in the joint) and Patella injury (for example, knee cap injury caused by tight tendons and incorrect patella positioning, patella tendinitus and cartilage damage).
Sports injury rehabilitation begins in the first 3 days after the soft tissue injury. The first priority is RICER treatment. This stands for Rest, Ice, Compression, Elevation and immediate Referral to an injury specialist to establish the exact nature of the injury and recommend initial treatment.
For the next 3 weeks rehabilitation consists of 2 important elements. The first is managing the formation of scar tissue with a physiotherapist and the second is to restore the function of the legs by being active. Being active will ensure that oxygen and nutrients are supplied to injured areas and the lymphatic system can remove waste products. During rehabilitation the primary focus is to regain joint and muscle flexibility (range of motion), strength, power, endurance, balance and proprioception (special positioning and coordination of limbs) in gentle work out routines.
In the final 3 months of injury recovery the focus of the conditioning stage is to reduce the risk of future injuries by identifying the likely causes of the original injury (e.g. muscle imbalances, incorrect gait) and eliminating them in more strenuous work out routines! (e.g. to restore muscle balance, improve muscle strength and flexibility).
Whatever part of the body is injured it is important to remember that it is part of a larger system and can never be treated in isolation. In the case of the knee for example, it is stabilised and mobilised by both the main lower and upper leg muscles. This means that leg work out routines are necessary.
The first priority is to regain the full knee joint range of motion with simple bending and straightening exercises followed by gentle rotations. This should be followed by slightly more intense leg stretching exercises (e.g. calves, hamstrings and quadriceps) and isometric exercises (e.g. pushing against a wall with the foot whilst keeping the ankle still).
Once some of the strength and flexibility has been regained gym machines provide a safer unsupervised way of strengthening the legs (e.g. calf raises, leg curls). Alternatively a certified personal trainer can provide supervised free weight exercises.
In the final rehabilitation stage it is necessary to restore the ability of the nervous system in the injured area to control the position and function of muscles, tendons and ligaments. Most soft tissue injuries will lead to nerve damage and the body must be retrained to control balance and proprioception. Some of the exercises include standing on one leg with/without the eyes shut and the use of specialist equipment such as balance disks, BOSU's and Swiss balls. Proprioception exercises include training drills used in a client's sport (e.g. dribbling with a football) and plyometrics (e.g. jumping, hopping, skipping, bounding, figures of eight).
With the basic leg function restored the conditioning stage involves client specific work out routines and the use of a certified personal trainer is recommended. The objective is to identify potential causes of the injury and use specialist work out routines to minimise or eliminate them. This often means strengthening and increasing the flexibility of certain parts of the body and/or recommending lifestyle changes (e.g. being more active, eating more healthily, wearing foot insoles).
Much of this approach also applies to knee surgery recovery but it is essential to ensure that for example, a personal trainer works in close conjunction with the medical care provider (e.g. injury consultant) to ensure that the specific needs of an individual's situation are taken into consideration.
