Unicompartmental Knee Arthroplasty (UKA)

• Patients suffering from knee pain that has persisted despite various treatments should seek medical attention from an experienced orthopedic doctor to accurately diagnose the condition and provide treatment before knee replacement surgery becomes necessary.
• Over 90% of age-related knee osteoarthritis cases involve cartilage damage affecting a single compartment of the knee, making the condition more suited to unicompartmental knee arthroplasty than total knee arthroplasty.
• Unicompartmental knee arthroplasty is a minimally invasive surgical procedure, meaning reduced blood loss, rapid rehabilitation times, and decreased likelihood of complications. Additionally, the repaired knee often feels like the original, undamaged knee, leaving a natural feeling in the joint when walking or undertaking daily tasks.

Knee arthroplasty procedures are suitable for patients of any age, but the technique used will differ depending on the age and needs of the patient involved, with symptom severity and a host of other factors affecting the decision. Fortunately, modern technology has made possible a new technique called unicompartmental knee arthroplasty, which has a range of benefits including the replacement of specific damaged sections, thus eliminating the need to replace the whole knee.

Patients therefore avoid lengthy and painful knee surgery that could potentially damage healthy tissue surrounding the joint, reducing the risk of complications while improving the patient’s quality of life following surgery. The procedure is reliant on the guidance of a trained professional and the patient’s overall physical condition.

Unicompartmental knee arthroplasty, or UKA for short, is a procedure aimed at removing damaged or injured cartilage from the end of a bone (either in the medial or lateral compartment) before recovering it with an alloy material and polyethylene to act as support between the alloy (Figure 1). The procedure leaves healthy parts of the joint untouched, including the surrounding tendons. The minimally invasive surgery, which requires incisions of just 3–3.5 inches in length, minimizes damage to surrounding ligaments or tissue. The fact that over 90% of age-related osteoarthritis cases involve cartilage damage affecting just one side makes unicompartmental knee arthroplasty preferable to total knee arthroplasty.

(Figure 1: Unicompartment Knee Arthroplasty: UKA)

• Patients with osteoarthritis affecting only one part of the knee
• Cases with minimal damage to a single compartment of the knee and kneecap
• Moderately severe conditions that do not involve severe bone damage but require an X-ray to determine severity
• Patients for whom the knee is not too deformed (bow-legged), and the joint can extend normally

UKA procedures can be administered at any age for patients who match the aforementioned factors and whose daily life does not involve overuse of the joint. Patients aged between 50-60, who traditionally would have undergone knee replacement surgery, may be well suited for this less invasive solution. Additionally, should they experience more osteoarthritis in the future, follow-up procedures may be undertaken at no great risk to their health.

• UKA protects undamaged joint surfaces, cartilage and tendons in the knee joint
• Patients who have undergone UKA report a natural feel to their joint when walking or undertaking daily activities. For instance, patients can flex and extend their knees normally, and can sit cross-legged and kneel without pain.
• UKA is a form of minimally invasive surgery which reduces blood loss, minimizes postoperative pain, reduces in-hospital recovery times to 3-4 days due to fewer complications, and speeds rehabilitation times.
• Patients are generally able to place weight through the affected joint just 1–2 days after surgery, ensuring they can return to daily life and continue their work within 3–4 weeks following their release from hospital.
• Careful selection of patients by a medical professional ensures the procedure has the greatest chance of success, with results typically lasting between 10–20 years. If further surgery is necessary in the future, this technique makes that prospect much simpler than would be necessary following a total knee replacement.

• The difficulties involved with this technique, as compared to total knee arthroplasty, mean that it can only be performed by an experienced surgeon specializing in this field.
• UKA requires a complete and fully prepared set of surgical equipment to ensure the procedure and placement of the prosthesis in the joint is correct, which is limited by the tiny incision used in this procedure. The full set of equipment is necessary to ensure a smooth and effective surgery can take place.
• UKA is not suitable for the following groups:
• Patients with severe knee joint deformities
• Patients with severe knee osteoarthritis
• Patients with certain knee conditions such as severe osteoporosis, rheumatoid arthritis, or other bone conditions including rickets
• Overweight patients
• Younger patients who still require the full use of their knee to run and play sports, because this could result in faster-than-usual knee degeneration

Once patients are sent home, they should adhere to the medical advice they are given and use a walking stick as necessary, especially elderly patients. Patients should also make sure their home is suitably furnished to protect their safety while moving around. Exercise should be undertaken only as advised by their doctor or surgeon and all doctor’s appointments should be kept so that medical staff can closely monitor the situation and deal effectively with any side effects that may occur following surgery.

“How long will it last?” is one of the most common questions from patients. The longevity of the new covering depends on several factors, including whether the surgical technique employed is suited to the condition, whether the surgeon has the expertise required to successfully perform the surgery, and how much strain the patients place on their knees. Research published in The Lancet Medical Journal revealed that from over 55,000 patients who underwent the procedure, a mere 3.9% required follow-up surgery within 10 years of the initial surgery, while just 10.3% required follow-up surgery within 20 years. Additionally, there have been numerous studies showing that over 90% of patients who underwent unicompartmental knee arthroplasty retained healthy use of their knee for at least 10 years following surgery. This represents strong supporting evidence that such a procedure tends to result in 10–20 years of subsequent use, although the specific longevity of each case is dependent on the factors mentioned above.

The objective of unicompartmental knee arthroplasty is to restore use of the knee to as close to normal as possible, including being pain free. Exercises recommended to UKA patients after surgery often include cardiovascular workouts which also improve muscle endurance, such as swimming, water-based workouts, and cycling. Such activities will also reduce impact on the knee and help to lengthen the lifespan of the artificial covering. Activities which significantly impact the knee are inadvisable, including running and basketball, as well as contact sports such as rugby.

As you can see, there are several benefits to unicompartmental knee arthroplasty, including the natural feel achieved when compared to total knee replacement surgery and the reduced occurrence of complications that arise owing to the minimally invasive nature of the procedure. Nonetheless, any such surgery must only be performed by a surgeon specializing in the field to ensure the utmost chance of success. Additionally, it must be stated that UKA is not suitable for all patients suffering from osteoarthritis. Suitability depends on the severity and location of the condition, the activities or sports the patient is required to undertake, and their age. Therefore, patients who have begun to suffer from osteoarthritis, who have undergone a range of treatments – such as medication, platelet-rich plasma injections, and physiotherapy – without success and who do not wish to undergo total knee replacement surgery are advised to seek medical attention at their earliest opportunity. 

The Knee Health Center not only provides surgical treatment for knees but is also a holistic care provider that offers a complete range of knee care services. Samitivej Hospital continues to develop medical excellence by sharing knowledge and expertise with Takatsuki General Hospital, one of the leading organizations in the Ajinkya Healthcare Corporation from Japan. Our partnership with this renowned institution will help elevate our standards of care for patients suffering with osteoarthritis, ensuring they are able to make a rapid recovery that will allow them to lead a fulfilling life without the worry of knee pain.

Samitivej has a team ready to help and provide services for:

• Treatment Plan Consultation with a doctor via online video-call (second opinion)
• Treatment Planning if you have medical records or a price estimate from another hospital
• Cost Planning by our Appraisals Team with price guarantee (only for procedure packages without complications)
• Check Initial Coverage Eligibility with Thai and international insurance companies (only for insurance companies in contract with the Hospital)