The knee joint is formed between the two large prominences at the lower end of the thigh bone and two corresponding semicircular pits at the top of the shin bone, that are made deeper by two shallow cups on each side known as the cartilages (menisci) of the knee. It is a very strong hinge joint that can bend and straighten and is made more stable on twisting movements by several ligaments (strong ‘elastic bands’) that act as restraints to protect the joint.
Arthritis of the knee
Different forms of arthritis can affect the knee joint: osteoarthritis, inflammatory arthritis or traumatic arthritis. All of them will present with a particular pattern of pain and stiffness and it will be hard to bend and fully straighten the knee. Swelling may be present according to the degree of inflammation in the joint.
Physiotherapy can help with traumatic arthritis (that is usually associated with ligament injury) when any ligamentous damage will be treated with a specific massage technique called frictions before encouraging active movement in the knee to keep the ligament free. Massage, ice and electrotherapy can be used to reduce swelling and pain. If the problem has been there for over six weeks the ligament will need to be treated with manipulation to restore normal movement.
In osteoarthritis there may be persistent thickened swelling of the joint and this can be treated with deep tissue massage and electrotherapy. Mobilisations and stretching techniques will be applied with a home exercise programme to increase muscle strength and movement.
An anti-inflammatory steroid injection is more appropriate for the knee with inflammatory arthritis although advice on maintaining muscle strength and movement within the pain free range is appropriate as aftercare.
Loose body in the knee
Loose bodies are small fragments of cartilage or bone that can form in joints; particularly the hip, knee and elbow.
Loose bodies don’t have to cause problems and they can often be stable and fixed within the joint space. If they are free in the joint they may become trapped between the bony joint surfaces where they may give rise to twinges of pain, locking of the joint or blocked or ‘springy’ movements.
A loose body in the knee joint causes twinges of pain, swelling and the sensation of giving way. There may also be the sensation of the knee locking but that usually passes quite quickly. If the knee remains locked or needs manipulation to unlock the joint then an orthopaedic opinion is normally required as an arthroscopic (key hole) investigation may be indicated. The condition is most commonly associated with osteoarthritis in the knee or a flap of cartilage within the knee may also cause similar symptoms.
Physiotherapy can help by applying a special technique that stretches through the joint to give the loose body room to move, and then applying a few sharp flicks to jolt the loose body into a more comfortable position.
Medial collateral ligament sprain at the knee.
The collateral ligaments of the knee lie on either side of the joint and restrict sideways movement. The wider ligament is on the inside of the joint where it helps to resist torsion with the foot fixed and the knee bent – as in twisting movements whilst playing football, skiing etc. In that position the ligament can be overstretched and because it attaches closely to the joint covering (capsule) it can set up a traumatic arthritis with swelling, pain, stiffness and limitation of movement. Pain will be felt on stretching the ligament with a sideways movement of the knee. In the acute situation, the patient may need to be given crutches to walk.
Physiotherapy can help in both the acute and chronic stages, when the problem may have persisted for six weeks or more. In the acute stage ice and massage can be applied to the joint to reduce swelling and pain. A specific massage technique called frictions is applied across the tender site to maintain movement and bending and straightening of the knee is encouraged in the pain free range. Electrotherapy, usually ultrasound, can be applied to the ligament to reduce pain and to promote healing.
In the more chronic stage, scar tissue will have formed that can restrict the extremes of bending and straightening. Frictions are applied with a smart manipulative technique at the end of each movement to allow the joint to move more freely. Vigorous bending and straightening of the knee is encouraged to keep the knee moving normally after treatment.
Coronary ligament sprain
The coronary ligaments attach the edges of the cartilages (menisci) in the knee to the top edge of the shin bone. They provide some elasticity to movement to protect the cartilages. They can be sprained with a twisting movement of the knee or a forced straightening of the knee (hyperextension) and can co-exist with an injury to the cartilages themselves. The patient usually complains of a small area of pain on one side of the joint, usually at the front that is tender to touch on the sharp edge of the bone, especially when the knee is in the bent position. Stiffness and pain are felt on getting up after sitting for a long time in a cramped position, as in the cinema on a plane for instance.
Physiotherapy can help by applying a specific massage technique called frictions across the tender area and electrotherapy, especially ultrasound can help to relieve the pain and promote healing. There isn’t usually much swelling but ice can be used at home if necessary.
Bursitis at the knee
A bursa is a thin flattened fluid-containing balloon that acts as a buffer where muscles pass over bony points or it may lie between two muscles pulling in different directions to reduce friction. It can also protect bony prominences where they lie just under the skin.
Bursitis is inflammation of a bursa and it is associated with swelling and pain. Two main bursae may be involved in bursitis at the knee: the prepatellar bursa, the infrapatellar bursa and, less commonly, the pes anserine bursa.
Prepatellar and infrapatellar bursitis
The prepatellar bursa sits in front of the knee cap (patellar) and it may become inflamed after long periods of kneeling on all fours, leading to prepatellar burstis being known as ‘housemaid’s knee’. The infrapatellar bursa sits just below the knee cap and may become inflamed after long periods of kneeling with the pressure just on the knees, leading to infrapatellar bursitis being known as ‘clergyman’s knee’.
Physiotherapy can help by applying gentle soft tissue massage and electrotherapy, usually ultrasound, but the fluid may need to be drained from the bursa if progress is slow, and injection with anti-inflammatory steroid can help the condition to settle.
Pes anserinus syndrome
The pes anserine bursa sits behind the inside of the knee, tucked under three tendons as they pass to attach to the front of the top of the shin bone. For interest, the tendons splay out as they attach, looking rather like a goose’s foot – which in Latin is ‘pes anserinus’.
Pes anserinus syndrome may involve the tendons as well and can mimic a medial collateral ligament sprain. The condition is treated with local electrotherapy, usually ultrasound, and a specific massage technique called frictions can be applied to the tendon attachments as necessary. The bursa can also be injected with anti-inflammatory steroid if symptoms persist.
The patellar tendon passes from the quadriceps muscle in the front of the thigh to attach to the bony bump at the top of the shin. The knee cap (patella) lies superficially within the tendon at the front of the knee. The patellar tendon complex has to withstand considerable forces as it provides a constraint or brake to the knee bending, as in coming downstairs or landing on the bent knee in sports. Problems can occur in the soft tissues around the margins of the knee cap and the most common site for patellar tendinopathy is at the lower point of the knee cap where the condition is known as ‘jumper’s knee’.
The patient will complain of pain in the front of the knee, with tenderness, usually on either side of the point of the knee cap. The pain comes on with overuse and will be felt on running, jumping and going downstairs. Straightening the knee against resistance will bring on the pain.
Physiotherapy can help using a specific massage technique called friction across the tender area and teaching special high load exercises to restore tendon health. Electrotherapy may be used, particularly ultrasound, to help to relieve pain and promote recovery.
If symptoms persist local injection with ant-inflammatory steroid can be used, that must be followed by a period of resting form the aggravating activity, and there is also some evidence that shock wave therapy can help with chronic tendinopathy.
Tendinopathy of the insertions of the hamstring muscles.
The hamstring tendons attach below the knee: one attaches to the top of the outer bone in the lower leg (fibula) and the other two attach to the inner side of the upper shin bone. Tendiopathy can come on with over use or a sudden spurt of movement and the patient will complain of pain on walking, running etc at either the inside or outside of the knee, where there will also be local tenderness. Bending the knee against resistance will also bring on the pain.
Physiotherapy can help by using a specific massage technique called frictions across the tender site. Electrotherapy may be used, particularly ultrasound, to help to relieve pain and promote recovery. Resting from the aggravating activity will be advised until the symptoms settle fully to prevent recurrence.