Joint Replacement

What is a joint?

A joint is where two or more bones come together. It is connected by thick tissues called ligaments. The smooth layer that covers the end of each bone is called cartilage. This is designed to create smooth, pain free and frictionless movement for the joint. Each joint also has synovium, which is a fibrous tissue envelope that contains fluid to reduce wear and friction in the joint.

Why is joint replacement needed?

Cartilage can become damaged or diseased over time causing pain and stiffness of the joint. When this happens a person often avoids using the joint because the pain is so severe. Lack of movement causes the muscles around the joint to weaken and can make the joint even harder to move. Physical examinations, x-rays, and other laboratory tests help the physician determine the extent of the damage in the joint. If all other treatments have been unsuccessful to reduce pain, then a joint replacement will be considered. The entire joint or “total joint” replacement is not always needed. In some cases, specific parts can be replaced instead of the whole joint. However, if the entire joint is damaged a total joint replacement can be performed. “Currently, over 400,000 hip and knee replacements are performed in the United States annually. “ American Academy of Orthopaedic Surgeons (http://orthoinfo.aaos.org/topic.cfm?topic=A00510)

What is involved in a replacement?

In all replacements an anesthetic is administered in order to perform the operation. Knee and hip replacements may be the most common, but replacements can be performed on other joints in the body i.e. shoulder, elbow, and ankle. The materials used in a joint replacement are designed to imitate normal joint movement. Prosthesis (joint replacement components) are typically made up of a metal piece that closely fits a matching plastic part. Sometimes to anchor a prosthetic to the bone, plastic bone cement may be used. Cement is not always used, as some prosthetics are developed to lock and fit together directly. Depending on age, one may need to have parts of their replacement revised. Physicians and scientists are working to prolong the longevity of the replacement parts. As with all operations there is small chance of complications. Some complications that could possibly be involved with joint replacements include: blood clot, nerve injury, infection, excessive wear, loosing, dislocation or prosthetic breakage. “Joint replacement surgery is successful in more than 9 out of 10 people. When complications occur, most are successfully treatable.” American Academy of Orthopaedic Surgeons (http://orthoinfo.aaos.org/topic.cfm?topic=A00233)

For information on a specific joint replacement, click to learn more

Shoulder

Click Here Learn More
Shoulder replacements may not be as widespread as knee replacements, but they are just as effective at alleviating joint pain. When nonsurgical treatment ceases to help ease pain it may be time to talk to your physician about shoulder replacement surgery. Shoulder replacement surgery can help you get back into your everyday activities once more.

Anatomy and Description

The shoulder is composed of your humerus (upper arm bone), scapula (shoulder blade), and clavicle (collar bone). It is a ball-and socket joint meaning there is a ball (top of the humerus) that fits into a shallow socket located in your shoulder blade known as the glenoid. The surfaces of these bones, where they touch, are covered in articular cartilage which is a smooth matter that shields the bones and allows them to move trouble-free. Synovial membrane (slim, smooth tissue) coats the remaining surfaces of the joint. When the joint is healthy the synovial membrane produces a solution that works as a lubrication for the cartilage and prevents friction in the shoulder. Shoulder stability is provided by muscles and ligaments that surround it. The shoulder has the greatest range of motion out of all the joints in the body as a result of these structures.
Damaged parts are removed and replaced in shoulder replacement surgery. Prosthesis’s (artificial parts) are used to replace the damaged areas of the shoulder. During the surgery either the ball (top of the humerus) or the entire ball and glenoid (socket) are replaced.

Causes

Multiple conditions can cause shoulder pain and debilitation.
• Osteoarthritis – arthritis from wear and tear that is age related
• Rheumatoid Arthritis – Synovial membrane that covers the joint develops inflammation and thickens
• Post-traumatic Arthritis – fractures or tears in the tendons or ligaments of the shoulder may damage the articular cartilage over time
• Rotator Cuff Tear Pathology – a big, untreated rotator cuff tear may lead to damage in the joint cartilage and arthritis
• Avascular Necrosis (Osteonecrosis) – the blood supply to the bones is interrupted and bone cells die causing damage to the shoulder joint and arthritis
• Severe Fractures – when the upper arm shatters it can be difficult to piece back together and blood supply may not return properly to the bone
• Failed Previous Shoulder Replacement Surgery – this is uncommon, but if it occurs it most likely would be from either the implant loosening, prosthesis wear, infection, or dislocation

Evaluation and Treatment Options

An evaluation may consist of; medical history discussion, physical examination, x-rays, occasional blood test, magnetic resonance imaging (MRI) scan, and/or bone scan.
Several treatment options are available.
• Total Shoulder Replacement –typically entails the replacement of arthritic surfaces in the joint with a metal ball attached to a rod and a plastic socket. The surgeon may choose to cement or press fit the prosthesis. Cement is used when the bones are soft, tendons torn beyond repair or if the bones are badly worn. Most of the time cement is used. However, if the bone is in good condition the press fit option may be used instead.
• Stemmed Hemiarthroplasty – only the ball is replaced in this surgery. A metal ball and stem similar to that in the total shoulder replacement is used in the Hemiarthroplasty. Sometimes the physician may not know which procedure will be necessary (total or hemiarthroplasty) until they are in the operating room.
• Resurfacing Hemiarthroplasty – only the joint surface of the ball is replaced. A cap like prosthesis is used instead of the entire ball and stem prosthesis. This surgery has bone preserving advantages and helps young patients reduce the risk of the prosthesis to wear or loosen.
• Reverse Total Shoulder Replacement – very similar to the conventional total shoulder, the reverse total shoulder replacement simply installs the metal ball on the shoulder bone and the socket on the humerus. This surgery may be necessary because a total shoulder replacement has failed, a rotator cuff is completely torn causing arm weakness, pain persists, or the arm is debilitated from hindered range of motion.

Physical Therapy following shoulder replacement

Physical therapy usually begins after your first follow up appointment with your surgeon. Initial physical therapy goals include restoring range of motion, decreasing pain and swelling, and improving muscle function. Your physical therapist will help you safely return to your daily activities including work and leisure activities.

Knee

Click Here Learn More
Decreasing pain and restoring knee function is the goal of knee replacements. Not all knee replacements are the same. Sometimes the knee is only moderately injured and a partial knee replacement (unicompartmental/MAKOplasty) is all that is necessary. Patients with severe damage may, however, require a total knee replacement. The surgery will reduce pain, deformity, and help resume daily activities. If knee pain does not decrease from nonsurgical treatments interventions such as walking, supports, physical therapy, or medication you may want to talk to your physician about knee replacements.

Anatomy

The knee is the largest joint in the body and is made up of the femur (thighbone), tibia (shinbone), and patella (kneecap). Where the end of each bone touches is articular cartilage that protects the ends of the bone and allows them to glide smoothly. C-shaped wedges known as menisci are located between the femur and tibia and cushion the joint from shock. Synovial membrane covers the rest of the joint surfaces and releases fluids so the knee can be lubricated and move without friction. There are three different compartments of the knee. These three compartments are the lateral (outside of the knee), medial (inside of the knee), and the patellofemoral (between the femur and patella in the front). The knee gets its strength from thigh muscles and is stabilized by ligaments that hold the tibia and femur together.

Cause and Symptoms

Arthritis is the most common form of disability and chronic knee pain. Although there are many different types of arthritis three types are the major cause for knee pain. These three include osteoarthritis, rheumatoid arthritis, and post-traumatic arthritis.
Symptoms include:
• Severe knee pain or stiffness
• Moderate to severe pain while at rest
• Knee deformity
• Chronic inflammation and swelling
• No improvement with nonsurgical treatments.

Evaluation and Treatment

In the evaluation for both a partial and total replacement the physician will go over your medical history with you. They are looking to see if the pain encompasses the whole knee or if it is just on the inside or outside portion of the knee. A physical examination will be performed to determine range of motion, location of pain, alignment, ligament quality, stability, and strength. Some image testing may be ordered such as x-rays or magnetic resonance imaging (MRI) to determine the extent of damage.
For both partial and total knee replacements the day of surgery you will be admitted into the hospital. You will discuss with your doctor the type of anesthesia that is best for you. Either general anesthetic (you are put to sleep) or spinal anesthetic (numb from your waist down and awake) can be used.

Partial Knee Replacement (MAKOplasty) – through an incision on the front of the knee the surgeon will search the three compartments to find damaged cartilage. If the damage is restricted to one side of the knee the surgeon will continue with a partial knee replacement. However, if it is discovered that the knee is damaged beyond just one side then a total knee replacement may be performed. Your surgeon will discuss this possibility before the surgery and a contingency plan will be signed. When the knee qualifies for a partial replacement, a special saw is used to clean out any damaged cartilage in that compartment. At the end of the femur and tibia, on the damaged side, metal components cap the ends and are held in place typically with cement. Between the metal components, a plastic insert is placed to help the knee move smoothly. Once the surgery is complete you will be taken to the recovery room and monitored as you recuperate from anesthesia. Once you have completely recovered you will placed in your hospital room. Makoplasty partial knee resurfacing is a treatment option for early to mid stage osteoarthritic knees involving only medial, lateral or patellafemoral. There is a bicompartmental option for medial and patellfemoral together. Only the affected portion of the knee is replaced leaving healthy bone and ligament ACL (anterior cruciate ligament) and PCL (posterior cruciate ligament). MAKOplasty is an advanced partial replacement that uses RIO (robotic arm interactive orthopedic system). MAKOplasty allows for more consistant results and a more accurate implant than traditional partial knee replacements. CT scans are taken of the knee to create a 3D model for development of a pre-surgical plan based on the patient’s unique anatomy. *Learn more about MAKOplasty

Total Knee Replacement – through an incision on the front of the knee the surgeon will remove all of the damaged cartilage throughout the entire knee along with some of the underlying bone. Metal components are placed on the end of the femur and tibia to resurface the joint. The pieces are held in place with either cement or “press-fit” into the bone. A plastic button is sometimes placed on the underside of the patella. This depends on the surgeon and the case. Finally, a plastic piece is placed between the two metal components to help the knee move smoothly. Once the surgery is complete you will be taken to the recovery room and monitored as you recuperate from anesthesia. Once you have completely recovered you will placed in your hospital room. A total knee replacement won’t allow you to do more then you could before arthritis built up, but it does reduce pain dramatically and allows you to participate in daily activities.

Recovery

Although you will be in the hospital for a shorter amount of time with a partial knee replacement (MAKOplasty), most everything is the same. You will participate in pain management, blood clot prevention, pneumonia prevention, and physical therapy. With partial and total replacements you will begin to bear weight immediately after surgery. With a total replacement may be placed on a continuous passive motion (CPM) machine to generate knee movement (this depends on physician preference if one is utilized or not). This will help with swelling and blood circulation. Physical therapists work with both partial and total replacements to help gain range of motion and restore strength and function. They will help you get back on your feet and back to your daily activities quickly after surgery. MAKOplasty patients may go home the day of surgery if they are able to walk safely with the physical therapist. Total knee replacements are generally in the hospital 3 days then discharged to home or inpatient rehab depending on each individual and their progress.

Physical Therapy Following Knee Replacement

Physical therapy following knee replacement focuses on restoring range of motion, decreasing pain and swelling, and improving muscle strength. Each patient is evaluated by a physical therapist and an individualized treatment plan is developed. The treatment and goals are established based on findings during the evaluation, prior level of function, and patient goals both pre-operative and postoperative.

Hip

Click Here Learn More
Hips can be damaged from arthritis, fractures, or other conditions. If nonsurgical treatments do not help relieve symptoms, then hip replacement might be your answer. Hip replacements can help relieve pain, restore motion, and help you return to your daily activities. Depending on your situation one of two types of hip replacement may fit you better. A total hip replacement or hip resurfacing may be a better fit. Both are similar, but there are important differences.

Anatomy

The hip is one of the largest joints in the body. It is a ball-in-socket joint which is formed by the ball of the femur (upper thighbone) and the acetabulum (part of the pelvis bone). Articular cartilage (a smooth tissue) covers the ends of the bone as a cushion and allows them to move easily. The hip joint is encased by a synovial membrane that produces a small amount of fluid to lubricate the cartilage and prevent friction. Connecting the ball to the sock is the hip capsule which also provides stability for the hip joint. 3

Causes and Symptoms

Arthritis is the most common cause of constant hip pain and disability. The most common forms of arthritis that cause hip issues are: osteoarthritis, rheumatoid arthritis, and post-traumatic arthritis. Other causes of hip pain can come from avascular necrosis which is caused by lack of blood flow to the femoral head. The femoral head collapses due to the lack of blood flow and arthritis takes over. A hip dislocation or even a fracture can create avascular necrosis as well as some diseases. Child hip disease may also be the cause of hip pain. Although the childhood disease may have been treated arthritis can set in with age because the joint may not have grown normally or the joint surface has been affected.
Symptoms include:
• Daily activities limited from pain
• Pain continuation even while resting
• Leg movement limitation due to stiffness
• Nonsurgical treatments do not reduce pain or restore function

Evaluation and Treatments

When an orthopedic surgeon evaluates you, they will go over your medical history to learn about your general health, pain levels, and how they hinder your daily activity. They will also complete a physical exam to test your range of motion, strength, and alignment. Imaging tests like x-rays or even magnetic resonance imaging (MRI) may be issued to explore the extent of the damage to the hip.

Hip Resurfacing (MAKOplasty) – you will be admitted into the hospital the day of surgery. Anesthesia will be discussed by you and your surgeon and either general anesthesia (put to sleep) or a spinal anesthetic (numb from the waist down and awake) will be chosen. Through an incision in your thigh, the surgeon will dislocate the ball from the hip socket. The ball is then trimmed with specialty power tools and a metal cap is cemented over the ball. Cartilage that lines the socket is removed with a reamer (specialty power tool) and a metal cup is placed in the socket. The metal cup is held in place by friction from the bone and metal. The metal covered ball is then put back into place and the incision is closed up. After the procedure is finished, you are taken to the recovery room to be monitored during your recovery from anesthesia. Then you will be taken to your hospital room for the remainder of your stay. Hip resurfacing replaces the acetabulum in the same way as a traditional hip replacement, but allows bone conservation with resurfacing the femoral head.

Total Hip Replacement – just as in the resurfacing procedure you will be admitted into the hospital. Anesthesia will be discussed by you and your surgeon and either general anesthesia (put to sleep) or a spinal anesthetic (numb from the waist down and awake) will be chosen. Through an incision in your thigh, the surgeon will dislocate the ball from the hip socket. The ball is then removed from the femur and a metal stem is placed into the now hollow center of the femur. This is either cemented in or “press-fit” so the bone can grow to it. A metal or ceramic ball is then attached to the stem to replace the previous ball on the femur. Cartilage that has been damaged in the socket is then removed and a metal socket replaces it. It is sometimes held in place with cement or screws. A spacer made of plastic, ceramic or metal is placed between the ball and socket to allow for smooth movement. After the procedure is finished, you are taken to the recovery room to be monitored during your recovery from anesthesia. Then you will be taken to your hospital room for the remainder of your stay. Hospital stay is typically 3-5 days after which you will discharge to your home or inpatient rehab depending on each patient and their progress.

Recovery

With both procedures, you will probably be in the hospital for a few days. After a hip surgery procedure you may bear some weight immediately with an assistive device and the assistance of a physical therapist. This may also depend on your physician preference and bone strength. Walking assistive devices may be used until it is comfortable for you to walk on your own. Pain management is an important part for both procedures. If your pain becomes an issue, please notify your surgeon. Physical therapy will be necessary to re-establish range of motion and increase strength. This is crucial to your recovery.

Hip Precautions

Hip precautions to avoid dislocation of the prosthesis for at least the first 6 weeks after surgery:
• Do not cross your legs
• Do not bend your hips more than 90˚ (Do not bend over at your waist to dress or pick items off the floor)
• Do not turn your feet excessively in or out
• Use a pillow between your legs at night while sleeping

Physical Therapy Following Hip Replacement

Physical therapy following hip replacement focuses on restoring range of motion, decreasing pain and swelling, and improving muscle strength. Each patient is evaluated by a physical therapist and an individualized treatment plan is developed. The treatment and goals are established based on findings during the evaluation, prior level of function, and patient goals both pre-operative and postoperative.