By Nina Clark, CSCS
The prosthesis , or artificial joint, is inserted into the body to replace the damaged portion of the joint. There are two main fixations, cement or cementless.
In 1977, designs made it possible for the implant to attatch directly to the bone without using cement. The porous texture around the implant allows the bone to actually grow into the surface of the prosthesis. Cementless procedures require longer recovery time (6-12 weeks partial weight bearing) because bone growth is essential l for the prosthesis to be stable. The cementless technique is usually used for younger patients and those who are more active. This technique can be used in both hip and knee replacements.
Cemented joints recovery is very different. In this procedure it takes 10-15minutes for the cement to harden into a solid substance, filling the crevices and acting as a strong sealer around the bone. This allows for almost immediate ability to walk post surgery, which can translate to a quicker rehabilitation. One disadvantage of this type of replacement is the possibility of the cement loosening around the prosthesis over time. For all implants, the prosthetic steam and the cavity within the bone must fit together precisely, since new bone cannot grow to bridge the gaps larger than 1-2mm.
Recovery from a total joint replacement can last anywhere from a few weeks to a few months. The two initial goals of physical therapy are to 1: prevent contracture or tightening of the muscles surrounding the joint and 2:to assist the client in increasing muscular strength and stability. Most importantly, physical therapy helps the patient to perform activities of daily living (Roblero, 2007). Crutches or a walker are often essential tools during the beginning or recovery but it is important to move away from using these devises as soon as it is appropriate. Each person recovers from surgery at a different rate depending on age, current physical condition, and medical history.
Total joint replacements are extremely successful in most people. Nonetheless, complications do occur and need to be made known. Blood clots can occur in the lower extremities due to decreased activity. Pain, swelling, and redness in the claves or thighs are indications of blood clots. Blood thinners, anticoagulants and exercise all help in reducing the risk for developing blood clots. Infection can occur at the surgical site or around the prosthesis. Warning signs include fever, abnormal redness or warmth around the joint, persistent swelling, and unusual pain with activity or rest. Antibiotics are usually given as with any surgery before, during or after the procedure is done to help prevent infections. Loosening of the prosthesis within the bone is one of the main long-term complications with a joint replacement. With excessive wear, the prosthesis may become unstable causing an increase in pain. This is most common with very overweight or active people both of which place an excessive amount of stress on the prosthesis. Dislocation of the hip is more common then any other prosthetic joint. This is where strength of the muscles and tendons around the joint are essential. The stronger the surrounding structure of any joint is the less likely it is to dislocate. Although hip dislocation is more common during the earlier stages of recovery, a risk continues throughout the lifespan of the replacement, especially if the muscles surrounding the hip are not strong. To limit this risk here are three tips. Limit the hip bending to 90 degrees, don’t let the affected leg cross midline of the body, don’t rotate the leg to far inward or outward when standing, walking or turning. Mitigating these movements will lesion the likelihood of dislocating the hip.
Strength Training & Exercise
All joint-replacement patients are strongly encouraged to continue regular exercise and stay active. If the muscles are allowed to weaken from inactivity, the patient is at increased risk of falling, which according to the American Association of Orthopedic Surgeons, falls are the leading cause of repeat joint replacement surgeries (aaos,org, 2004). The muscles around the surgery site are weakened from both the lack of activity prior to the surgery and from the incisions that have disrupted the muscles integrity. In a study published in 2005 (Mizner et. Al) showed in 1 month after a total knee replacement, quadriceps strength in the involved leg decreased by 62% compared with the preoperative test.
Low-impact activities are most appropriate for any patient these include walking, swimming, golfing, bicycling, and ballroom dancing. Activities that put a larger amount of stress on the joint include running, skiing, horseback riding, tennis, contact sports etc. As I previously mentioned the more stress you put on the joint the quicker it will wear down nevertheless, depending on what sport and activities you enjoy it may be worth the risk. The following are some exercise that will help you gain strength so that you can perform to help you strengthen you lower body in order to return to sports and activities you love.
- Recumbent bike
- Elliptical machine
1- Quad Push: sit or lie on the back with the involved leg straight. Push the back of the knee down toward the mat, attempting to straighten the leg as much as possible. Hold for 5 seconds. This strengthens the quadriceps.
2- Straight leg lift: lie lat or propped on the elbows with the involved leg straight. Bend the opposite knee. Keeping the knee straight, lift the leg approximately 12 inches off the mat. Hold for 5 seconds and repeat.
3- Side laying Abduction: lie on the side opposite of the involved joint. Bend the knee on the bottom and keep the upper knee straight. Lift the straight leg off the bottom leg. Hold for 5 seconds. Then lower the leg and repeat.
4- Side laying Adduction: lie on the side of the involved joint. Place the sole of the top foot behind the straightened bottom leg. Lift the bottom leg up off the mat. Hold for 5 seconds. Then lower and repeat.
1- Standing Knee Extension: Stand with the resistance band around the upper portion of the calf with the other portion of the band attached or something sturdy. Begin with knee slightly bent then straighten the knee against the resistance of the band.
2- Standing Knee flexion: The same set up as the extension but pull the band forward keeping the knee straight
1- Supine hamstring stretch
2- Standing hamstring stretch
3- Heel to Buttocks
4- Calf stretch