It is important to understand the options and risk and complications of surgery:

Total knee and partial knee replacements are usually performed on patients suffering from severe arthritis where the pain interferes with normal day to day activities and require the use of pain killers. Most patients are above the age of 55yrs. Before moving to the option of surgery it is important to have tried and considered the other non-surgical possible options.

The option of a partial knee replacement is made on the basis of the degree of osteoarthritis within the knee joint. If it is isolated to just one area, we will offer a partial knee replacement. This is verified initially on an MRI scan but ultimately decided when the surgery takes place. We always have the plan B and an option to divert to a total knee replacement if the other parts of the knee are more worn than expected on MRI or the ligaments are not intact allowing us to safely perform a partial knee replacement.

The national joint registry shows that the revision (redo) rate for partial knee replacements are higher than that for total knee replacements over a 7-10 year period. (Approx. 3% vs 6%).

Other alternatives include:

stopping strenuous exercises or work

Losing weight

Physiotherapy and gentle exercises,

Medicines, such as anti-inflammatory

Using a stick or a crutch

Using a knee brace

All surgery and treatment carry some risk these are the most common for a total and partial knee replacement:

Most Common 2-3% or higher risk of occurring

Pain: the knee will be sore after the operation. If you are in pain, it’s important to tell staff so that medicines can be given. Pain will improve with time. Rarely, pain will be a chronic problem. This may be due to altered leg length or any of the other complications listed below, or sometimes, for no obvious reason. 1 in 10 patients can have worse pain after surgery than before that con be permanent. Some patients will regret having surgery and wish they had not proceeded.

Bleeding: A blood transfusion or iron tablets. May rarely be required. Rarely, the bleeding may form a blood clot or large bruise within the knee which may become painful require an operation to remove it (Haemarthrosis).

Blood clots: a DVT (deep vein thrombosis) is a blood clot in a vein. The risks of developing a DVT are greater after any surgery (and especially bone surgery). DVT can pass in the blood stream and be deposited in the lungs (a pulmonary embolism – PE). This is a very serious condition which affects your breathing. We will give you medication to try and limit the risk of DVTs from forming. We will also ask you to wear stockings on your legs and may use foot pumps to keep blood circulating around the leg. Starting to walk and moving early is one of the best ways to prevent blood clots from forming. A DVT may be life threatening.

Knee stiffness: may occur after the operation, especially if movement post-operation is limited. Manipulation of the joint (under general anaesthetic) may be necessary.

Less Common Risks Less of occurring 1%:

Infection: You will be given antibiotics just before and after the operation and the procedure will also be performed in sterile conditions (theatre) with sterile equipment. Despite this there are still infections (approx. 1%). The wound site may become red, hot and painful. There may also be a discharge of fluid or pus. This is usually treated with antibiotics, but an operation to washout the joint may be necessary. In rare cases, the prostheses may be removed and replaced at a later date. The infection can sometimes lead to sepsis (blood infection) and strong antibiotics are required. The worst case would be that this infection could be a risk to your life or require you to lose your leg above the knee.

Prosthesis wear: Modern operating techniques and new implants, mean around 80% of knee replacements last over 15 years. In some cases, this is significantly less. The reason is often unknown. The plastic bearing is often the most commonly worn away part.

Nerve Damage: efforts are made to prevent this, however damage to the small nerves around the knee is a risk. This may cause temporary or permanent altered sensation around the knee. There may also be damage to the Peroneal Nerve, this may cause temporary or permanent weakness or altered sensation of the lower leg.

Bone Damage: the thigh bone may be broken when the prosthesis (false joint) is inserted. This may require fixation, either at time or at a later operation.

Blood vessel damage: the vessels at the back of the knee may rarely be damaged. This

may require further surgery by the vascular surgeons or very rarely amputation.

COVID 19 Risk: It is difficult to quantify at this time the true risk to developing COVID 19 due to your surgery and inpatient stay. We will ask you to isolate before and after surgery. You will also have a COVID 19 swab prior to admission. Despite this there is a risk of contracting COVID. If you did contract it having had surgery and an anaesthetic, you would be at an increased risk of developing breathing complications and this could be a risk to your life.

If you have any questions or concerns, please do not hesitate to contact us before your surgery.

Consent and understanding the expectations of patients is vitally important. We at Wessex Knee have created our new consent information sheets. These allow you to read at home and before your surgery everything we have discussed in clinic. Follow the link to the consent page to download the PDFs for each specific procedure.

We have done one for knee arthroscopy and meniscal surgery, Anterior Cruciate Ligament (ACL) and other ligament surgery, Patellar instability (MPFL) surgery, Total (TKR) and partial knee replacement and resurfacing surgery and revision knee replacement surgery.

Patellar or kneecap dislocations are part of the overall condition called patellofemoral instability. It is more common in children but can become recurrent and extend into adulthood.

It is a complex problem and causes knee pain and significant disability and restriction of your activities, sports and day to day life! Here a full run down of everything you need to know about what it is and how we can diagnose it and ultimately prevent it happening again and give you your life back.

Yours or your child's kneecap (patella) is usually right where it should be—resting in a groove at the end of the thighbone (femur - trochlear groove). When the knee bends and straightens, the patella moves straight up and down within this groove. Sometimes, the patella slides too far to one side or the other. When this occurs — such as after a hard blow or fall — the patella can completely or partially dislocate. Sometimes this can occur with a simple twist and is due to the laxity of the ligaments or under-development of the groove (trochlea). This is something you are born with.

When the patella slips out of place — whether a partial or complete dislocation — it typically causes pain and loss of function and can lock your knee. Even if the patella slips back into place by itself, it will still require treatment to relieve the knee pain and swelling that will follow. Be sure to take your child to the doctor for a full examination to identify any damage to the knee joint and surrounding soft tissues as the act of the knee cap dislocating and going back into joint can knock of the highly specialised articular cartilage that covers the surface of the joint. This is an emergency and may require urgent surgery. Contact us if this happens or attend ED.


There are a several ways in which the kneecap can become unstable or dislocate. In many cases, the patella dislocates with very little force because of an abnormality in the structure of yours or your child's knee.

A shallow or uneven groove in the femur can make dislocation more likely.

Some children's ligaments are looser, making their joints extremely flexible and more prone to patellar dislocation. This occurs more often in girls, and the problem may affect both knees.

Children with cerebral palsy and Down syndrome may have kneecaps that dislocate frequently due to imbalance and muscle weakness.

Rarely, children are born with unstable kneecaps causing dislocations at a very early age, often without pain.

In children or patients with normal knee structure, patellar dislocations are often the result of a direct blow or a fall onto the knee. This incidence is more common in high-impact sports, such as football or rugby.


We would want to examine your or your child’s knee and check to see how the leg is aligned and whether there is any rotational abnormalities that can increase the chances of patellar instability and recurrent dislocations. We also want to look for the laxity of the medial patellofemoral ligament (MPFL). tis is lax with hypermobility and in those where they have had damage to the ligament holding the knee cap in position. Patella Alta or the knee cap riding high can also increase the risk of dislocation.

MRI scans would be ordered to look at the smooth articular cartilage to check for damage and also to look at how well developed the groove the knee cap runs in is developed. In the acute injury this MRI is vital at excluding a significant cartilage injury that might need urgent surgery.

Surgical Treatment

If yours or your child's patella dislocates multiple times, or continues to be unstable despite physiotherapy and bracing, surgery may be recommended to correct the problem. The type of surgery will depend on the cause of the unstable kneecap.

Surgical treatments often involve reconstructing the ligaments that hold the patella in place. This surgery is sometimes performed arthroscopically—using a tiny camera and miniature surgical instruments inserted through small incisions. Other surgeries include realignment of the angle of the leg or rotation of the leg with an osteotomy, a tibial tubercle or tuberosity ostetomy to move the attachment of the patella on to the shin bone (tibia) to allow it to glide in a straight line in the groove (trochlea) and finally if the groove is under-developed we may need to recreate the groove with a trochleoplasty.

At Wessex Knee Mr Frame uses his 10 year experience in 3D printing to create models from CT scan of your knee to help plan the complex knee reconstruction surgery required to get you back on your feet.

If you have any questions or want to make an appointment contact us here.

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