What Is a Partial Knee Replacement?
A partial knee replacement is a surgery to replace one portion of your knee with artificial parts. Your knee contains three parts called compartments. There are three types of partial knee replacement, depending on which compartment your surgeon replaces:
-
Medial unicompartmental arthroplasty—Your surgeon removes and replaces the compartment on the inner side of your knee. This is the most common type of partial knee replacement.
-
Patellofemoral arthroplasty—Your surgeon removes and replaces your kneecap. People with previous trauma or repeated kneecap (patellar) dislocations are more likely to get this type of replacement.
-
Lateral unicompartmental arthroplasty—Your surgeon removes and replaces the compartment on the outer side of your knee. This is the least common type of partial knee replacement.
Partial vs. Total Knee Replacement
Your surgeon may recommend a total knee replacement if you have damage in more than one knee compartment. During a total knee replacement, your orthopedic surgeon removes and replaces the knee joint with metal and plastic.
Your surgeon usually also removes your anterior cruciate ligament (ACL) during a total knee replacement. Your ACL is a strong band of tissue that stabilizes your knee joint. You keep your own ACL in a partial knee replacement. As a result, your knee often feels more natural after a partial replacement.
Sometimes, it’s hard to tell how much knee damage you have on imaging tests. That’s why our surgeons often have both partial and total knee replacement implants available in the operating room. This allows them to perform a total replacement if they find knee damage in more compartments. They discuss the possibility of a total replacement with you before surgery to ensure you’re comfortable with this approach.
Who Is a Candidate for a Partial Knee Replacement?
Partial knee replacement may be right for you if you have damage in only one knee compartment. It can be a good choice if you are older. Older patients have a lower risk of wearing out their other knee compartments in their lifetime. A partial knee replacement can also be a good option for very young patients who want to delay a total knee replacement.
Some people are less ideal candidates for a partial knee replacement:
-
Body mass index (BMI) of 35 or higher
-
Low bone density or osteoporosis
-
Wear and tear (osteoarthritis) in more than one knee compartment
Find a Knee Specialist
What to Expect During Partial Knee Replacement Surgery
You get anesthesia to remain comfortable during the procedure. You may get spinal anesthesia, where your legs are numb, but you are awake. Or you may receive general anesthesia so you stay in a sleep-like state. It depends on your health conditions, the anesthesia provider’s insights, and your preference.
Your orthopedic surgeon follows several steps during the operation:
-
Makes a small incision along the side of your knee
-
Looks at your knee joint to assess the damage
-
Decides whether to perform a partial or total replacement
-
Removes damaged portions of your knee and replaces them with artificial parts
-
Closes the incision with absorbable stitches and surgical glue
Surgery usually takes around 90 minutes. You go to a recovery area for the anesthesia to wear off. You practice walking with crutches or a walker. Almost all patients return home the same day.
Partial Knee Replacement Recovery
Full recovery from a partial knee replacement takes about three months:
-
1–2 days—You ice your knee and take pain medication. You can move with crutches or a walker but you will be sore.
-
One week—You start physical therapy exercises. Our team uses a text message service that gives you daily exercise recommendations during recovery. You will likely stop taking narcotic medicines and can continue over-the-counter pain medications.
-
Two weeks—You see your orthopedic surgeon’s team to check on your recovery. Most people gradually stop using crutches around this time. You work with a physical therapist to regain your strength and range of motion.
-
Six weeks—You start feeling more like yourself and may want to resume some of your usual activities. We advise waiting to play sports or kneel on your new joint.
-
Three months—Most people get full clearance to resume all their activities.
Our orthopedic surgeons' research shows that people with partial knee replacements usually return to their prior activity levels. In our recent studies, up to 80% of people who skied or played racquet sports before they had surgery were able to resume these activities afterward.
How Long Does a Partial Knee Replacement Last?
The components of your replacement should last decades. Eventually, you may need revision surgery to get a total replacement if your other natural knee compartments wear out.
Why Choose Â鶹ѧÉú¾«Æ·°æ?
Our University Orthopaedic Services team includes expert surgeons skilled in a full range of knee replacement techniques. We regularly treat patients with complex needs from throughout the Mountain West region and beyond. Our surgeons are also active researchers who teach and train the next generation of experts.
Our comprehensive team includes nurses and medical assistants who help you prepare for surgery, answer all your questions, and put you at ease. Specialized physical therapists help ensure you experience the best outcome possible after surgery. We tailor care to your needs, always putting your unique concerns and preferences first.
Make an Appointment
Call 801-587-7109 to request an appointment with an orthopedic specialist. We don’t require referrals, but some insurance plans do. We recommend checking with your insurance provider before you schedule your appointment.
