Hip and Knee Joints
The hip joint, scientifically referred to as the acetabulofemoral joint (art. coxae), is the joint between the femur and acetabulum of the pelvis and its primary function is to support the weight of the body in both static (e. g. standing) and dynamic (e. g. walking or running) postures. The hip joints are the most important part in retaining balance. The pelvic inclination angle, which is the single most important element of human body posture, is adjusted at the hips. The knee joint joins the thigh with the lower leg and consists of two articulations: one between the femur and tibia, and one between the femur and patella. It is the largest joint in the human body and is very complicated. The knee is a mobile trocho-ginglymus (a pivotal hinge joint), which permits flexion and extension as well as a slight medial and lateral rotation. Since in humans the knee supports nearly the whole weight of the body, it is vulnerable to both acute injury and the development of osteoarthritis.
- Joint Arthritis
Osteoarthritis is the most common type of hip and knee arthritis which is characterized by progressive wearing away of the cartilage of the joint. As the protective cartilage is worn away by hip arthritis, bare bone is exposed within the joint. Arthritis typically affects patients over 50 years of age. It is more common in people who are overweight, and weight loss tends to reduce the symptoms associated with hip arthritis. There is also a genetic predisposition of this condition. Other factors that can contribute to developing arthritis include traumatic injuries to the joint and fractures to the bone around the joint.
- Signs and Symptoms
The most common symptoms of hip and knee arthritis are:
In the case of knee arthritis, in addition to the abovementioned symptoms, the following are also probable:
Evaluation of a patient with hip arthritis should begin with a physical examination and x-rays. These can serve as a baseline to evaluate later examinations and determine progression of the condition. In situations where a hip fracture is suspected but not obvious on x-ray, an MRI is the next test of choice. If an MRI is not available or the patient cannot be placed into the scanner a CT may be used as a substitute.
Treatment of hip arthritis should begin with the most basic steps, and progress to the more involved, possibly including surgery. Not all treatments are appropriate in every patient, and you should have a discussion with your doctor to determine which treatments are appropriate for your hip arthritis.
In the case of knee arthritis, Cortisone injections, Sinvisc and knee osteotomy and in the case of hip arthritis, Hip Resurfacing Surgery might also serve as a treatment criteria.
Joint Replacement Surgery
Joint Arthritis is the main reason of joint replacement surgeries in Hip and Knee. Hip fracture is the second reason for the former surgery and joint tumors might also bring the necessity for surgery.
Before the surgery starts, patient will have one of the following types of anesthesia:
- Hip joint replacement
Hip joint replacement is surgery to replace all or part of the hip joint with a man-made (artificial) joint. The artificial joint is called a prosthesis.
Your hip joint is made up of two major parts. One or both parts may be replaced during surgery:
The new hip that replaces the old one is made up of these parts:
After you receive anesthesia, your surgeon will make a surgical cut to open up your hip joint. Often this cut is over the buttocks. Then your surgeon will:
This surgery usually takes 1 to 3 hours.
After Hip Surgery, you will need to follow HIP PRECAUTIONS for 3 MONTHS unless otherwise advised by your surgeon. These activity restrictions will help your joint to heal and reduce the risk of hip dislocation. Things you CAN DO after hip surgery: DO sit on a raised chair or use a high-density foam cushion to increase surface heights. Use a raised toilet seat. DO use long-handled aids, such as a shoehorn and reacher, to help you dress and pick up items.
Do sleep with pillows between your legs for the first 3 months after surgery. You may require assistance placing the pillows or choose to use an extra-long pillow.
- Knee joint replacement
Knee joint replacement is surgery to replace a knee joint with a man-made (artificial) joint. The artificial joint is called a prosthesis.
During knee joint replacement surgery, damaged cartilage and bone are removed from the knee joint. Man-made (artificial) pieces, called prostheses, are then placed in the knee. These pieces may be placed in up to three surfaces in the knee joint:
You will not feel any pain during the surgery because you will have a type of anesthesia. After you receive anesthesia, your surgeon will make a cut over your knee to open it up. This cut is often 8 to 10 inches long. Then your surgeon will:
The surgery usually takes around 2 hours. Usually, artificial knees have both metal and plastic parts. Some surgeons now use different materials, including metal on metal, ceramic on ceramic, or ceramic on plastic.
After Knee Surgery, you will need to follow KNEE PRECAUTIONS for 3 months unless otherwise advised by your surgeon. These activity restrictions will help your joint to heal and reduce stiffness in the new joint.
- Why the Procedure is performed
The most common reason to have a hip/knee joint replaced is to relieve severe arthritis pain that is limiting your activities. Joint replacement is usually done in people age 60 and older, but many people who have this surgery are younger. Your doctor may recommend hip/knee joint replacement if:
But there are other reasons for replacing the hip joint which are:
Risks for any surgery are:
Hip/knee replacement surgery results are usually excellent. Most or all of your pain and stiffness should go away. Although some people may have problems with infection, loosening, or even dislocation of the new hip joint. Over time (sometimes as long as 15 – 20 years for the hip and 10 – 15 years for the knee) the artificial joint will loosen. You may need a second replacement. Younger, more active people may wear out parts of their new hip. It may need to be replaced before the artificial hip loosens.