United KingdomPigmented villonodular synovitis (or PVNS for short) is listed on the Office of Rare Diseases Research as a rare condition. It is a condition of the joint lining, characterized by pain and swelling as well as iron build-up inside the joint.
pigmented villo nodular synovitis (PVNS)
It is a disease in which the tissue lining a joint in the body begins to grow abnormally. The additional tissue in the joint can cause pain, limit movements or cause the joint to lock, and in some cases, can destroy the normal joint structure. The knee is most commonly affected by this condition, though it can occur in other joints such as the hip, shoulder, elbow, ankle, or wrist. The average age of diagnosis for this condition is 35 years
There are two types: the nodular form (where the abnormal tissue growth forms a single bump) and the diffuse form (where the entire lining of the joint grows unusually).
Causes
The cause of PVNS is unknown. Genetic changes associated with PVNS have been identified, but the evidence for a genetic cause is not conclusive.
Symptoms
In addition to joint pain and swelling, patients with localized PVNS will experience joint locking, catching, and instability. Patients with diffuse PVNS often present with a gradual onset of joint pain, swelling, and stiffness. In both types, symptoms may occur sporadically.
Treatment
In most cases of PVNS, surgery is the best treatment option. In the past, because of the high rate of surgical complications and local recurrence rates, physicians recommended observation (no treatment) until a total joint replacement was required. Today, with improved surgical techniques, the rate of surgical complications and local recurrence rates have decreased to such an extent that most patients are best treated with surgery. For people who are not good candidates for surgery, anti-inflammatory medicines and muscle-strengthening exercises can help alleviate the pain and swelling.
There are several surgical techniques to treat PVNS.
Recovery
Postoperative physical therapy is extremely important in getting you back to your daily activities. Specific exercises will help you regain strength and range of motion.
pigmented villo nodular synovitis (PVNS)
It is a disease in which the tissue lining a joint in the body begins to grow abnormally. The additional tissue in the joint can cause pain, limit movements or cause the joint to lock, and in some cases, can destroy the normal joint structure. The knee is most commonly affected by this condition, though it can occur in other joints such as the hip, shoulder, elbow, ankle, or wrist. The average age of diagnosis for this condition is 35 years
There are two types: the nodular form (where the abnormal tissue growth forms a single bump) and the diffuse form (where the entire lining of the joint grows unusually).
Localized
When the pain and swelling occurs in just one area of the joint, it is called localized PVNS. This type usually responds well to treatment.
Diffuse
When the condition involves the entire joint, it tends to be more destructive. Diffuse PVNS is more difficult to treat. It is significantly more common than localized PVNS.
When the pain and swelling occurs in just one area of the joint, it is called localized PVNS. This type usually responds well to treatment.
Diffuse
When the condition involves the entire joint, it tends to be more destructive. Diffuse PVNS is more difficult to treat. It is significantly more common than localized PVNS.
Causes
The cause of PVNS is unknown. Genetic changes associated with PVNS have been identified, but the evidence for a genetic cause is not conclusive.
Symptoms
In addition to joint pain and swelling, patients with localized PVNS will experience joint locking, catching, and instability. Patients with diffuse PVNS often present with a gradual onset of joint pain, swelling, and stiffness. In both types, symptoms may occur sporadically.
Treatment
In most cases of PVNS, surgery is the best treatment option. In the past, because of the high rate of surgical complications and local recurrence rates, physicians recommended observation (no treatment) until a total joint replacement was required. Today, with improved surgical techniques, the rate of surgical complications and local recurrence rates have decreased to such an extent that most patients are best treated with surgery. For people who are not good candidates for surgery, anti-inflammatory medicines and muscle-strengthening exercises can help alleviate the pain and swelling.
There are several surgical techniques to treat PVNS.
Arthroscopy (keyhole surgery)
Arthroscopic partial removal of the affected joint lining with the mass is the treatment of choice for localized PVNS today. Arthroscopy is commonly successful because recurrence rates of localized PVNS at the same site are very low.
Open Surgery (non-keyhole surgery)
In patients with diffuse PVNS with both the front and back of the knee involved (most patients), open surgery rather than arthroscopy is often the best treatment. Your doctor will need to remove the mass and the entire joint lining to treat diffuse PVNS.
Combined Arthroscopy and Open Surgery
When most of the mass is in the back of the knee, a combined surgical approach can be undertaken. The back the knee is treated with open surgery to remove the mass and joint lining, and the front of the knee is treated with arthroscopic removal of the joint lining. This combined method decreases the magnitude of surgery, allowing for an easier recovery. The recurrence rate at the same site is higher in patients with diffuse PVNS, but with proper surgical technique, the risk of recurrence can be minimized.
Total Joint Replacement
In its end stages, PVNS can cause extensive joint destruction. Once the joint has been significantly damaged, the best option to relieve pain and improve function is a total joint replacement.
Radiation Therapy
Radiation therapy can sometimes be used for patients with diffuse PVNS that involves major nerve, tendon, or vascular structures or lesions that recur after surgery. Radiation therapy is most commonly delivered via an external beam (treatment is directed from outside the skin to inside the joint). A newer method called intra-articular radiation (a radioactive fluid is injected into the joint with a needle) has been used as well. Radiation therapy is usually reserved for patients in whom standard surgery has not been successful.
Arthroscopic partial removal of the affected joint lining with the mass is the treatment of choice for localized PVNS today. Arthroscopy is commonly successful because recurrence rates of localized PVNS at the same site are very low.
Open Surgery (non-keyhole surgery)
In patients with diffuse PVNS with both the front and back of the knee involved (most patients), open surgery rather than arthroscopy is often the best treatment. Your doctor will need to remove the mass and the entire joint lining to treat diffuse PVNS.
Combined Arthroscopy and Open Surgery
When most of the mass is in the back of the knee, a combined surgical approach can be undertaken. The back the knee is treated with open surgery to remove the mass and joint lining, and the front of the knee is treated with arthroscopic removal of the joint lining. This combined method decreases the magnitude of surgery, allowing for an easier recovery. The recurrence rate at the same site is higher in patients with diffuse PVNS, but with proper surgical technique, the risk of recurrence can be minimized.
Total Joint Replacement
In its end stages, PVNS can cause extensive joint destruction. Once the joint has been significantly damaged, the best option to relieve pain and improve function is a total joint replacement.
Radiation Therapy
Radiation therapy can sometimes be used for patients with diffuse PVNS that involves major nerve, tendon, or vascular structures or lesions that recur after surgery. Radiation therapy is most commonly delivered via an external beam (treatment is directed from outside the skin to inside the joint). A newer method called intra-articular radiation (a radioactive fluid is injected into the joint with a needle) has been used as well. Radiation therapy is usually reserved for patients in whom standard surgery has not been successful.
Recovery
Postoperative physical therapy is extremely important in getting you back to your daily activities. Specific exercises will help you regain strength and range of motion.
Arthroscopy
Recovery from arthroscopic treatment for localized PVNS often requires a short course of physical therapy, after which you may return to normal activity.
Open Surgery
Because the open surgical removal of diffuse PVNS is extensive, there is an increased risk of postoperative stiffness. A more regimented and extensive physical therapy program is required for patients recovering from open surgery to treat diffuse PVNS. Recovery after open surgery involves an intensive, difficult, and prolonged physical therapy program. A return to normal daily activities could take months.
Differential diagnosesRecovery from arthroscopic treatment for localized PVNS often requires a short course of physical therapy, after which you may return to normal activity.
Open Surgery
Because the open surgical removal of diffuse PVNS is extensive, there is an increased risk of postoperative stiffness. A more regimented and extensive physical therapy program is required for patients recovering from open surgery to treat diffuse PVNS. Recovery after open surgery involves an intensive, difficult, and prolonged physical therapy program. A return to normal daily activities could take months.
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