Pigmented Villonodular Synovitis of the Knee Presenting as a Loose Body A Case Report CLARENCE WOODS,JR., M.D., CLEMENT 0. ALADE,M.D., VIRGINIA ANDERSON, M.D.AND MILTONE. ASHBY,M.D.
and pain on extremes of full motion as the mass would snap from beneath the patella. All plain roentgenograms were normal. A pneumoarthrogram was ordered but a contrast arthrogram was done and described as normal. On July 27, 1976 an arthrotomy was performed with a preoperative diagnosis of a loose body. A small amount of straw colored synovial fluid was encountered as a 3 x 2.5 cm tumor was discovered attached to the synovium immediately above the superior aspect of the medial femoral condyle by a 1.5 cm pedicle. The immediately adjacent synovium appeared grossly hypertrophic but no other joint abnormalities were noted. A limited local synovectomy was done in removing the mass. The postoperative course was without complication. The microscopic diagnosis was pigmented villonodular synovitis (Fig. 1).
Diffuse pigmented villonodular synovitis is a relatively rare condition most commonly involving the knee joint. The localized nodular form of this condition nearly always involves the knee joint and may be responsible for presenting signs and symptoms suggesting a loose body.'-3 The following case presentation adds further documentation to the cited literature suggesting that localized villonodular synovitis be considered as an occasional cause of knee symptoms and signs suggesting a loose body.
CASE REPORT C.H.A 21-year-old black woman was first seen in the orthopedic clinic at the Martin Luther King, Jr. General Hospital on July 14, 1976 complaining of intermittent locking, swelling and pain in her right knee of one year's duration. There was no history of trauma. She was aware of a movable body about the medial aspect of her knee. On physical examination a 3 X 2.5 cm nontender mass could be palpated adjacent to the medial border of the right patella which would disappear upon pressure beneath the patella. There was a mild effusion
DISCUSSION The localized form of villonodular synovitis may present as internal derangement of the knee. Rarely is this diagnosis made preoperatively. Though the prognosis is excellent following local excision when compared with the less optimistic results associated with total synovectomy for the diffuse variety, it would seem that consideration of this entity in the differential diagnosis of internal derangement would permit the occa-
From the Martin Luther King, Jr. General Hospital, Los Angeles, California. Received: December 3, 1976. 230
Number 129 November-December, 1977
Pigmented Villonodular Synovitir
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sionally encountered case to be diagnosed preoperatively. The air arthrogram is more accurate in detecting loose bodies than is arthrography utilizing contrast media.4 It is suggested that with a palpable loose body, not roentgenographically detectable in a nontrauma patient, a pneumoarthrogram may be of value in establishing a preoperative diagnosis of localized villonodular synovitis. SUMMARY A 21-year-old woman with a history of internal derangement of the knee and a palpable loose body was found to have localized villonodular synovitis at surgical exploration. REFERENCES 1. Byers,
P. D., Cotton, R. E.. Deacon, W.,
Lowy, M., Newman, P. H., Sissons, H. A. and Thomson, A. D.: The diagnosis and treatment of pigmented villonodular synovitis, J. Bone Joint Surg. 50-8:290, 1968. 2. Granowitz, S. P. and Mankin, H. J.: Localized pigmented villonodular synovitis of the knee, J. Bone Joint Surg. 49-A:122, 1967.
FIG. 1. Photomicrograph ( 2 5 0 )~. Giant cells with iron pigment visible typical of villonodular synovitis. 3. Jaffee, H. L.: Tumor and Tumorous Condi-
tions of the Bone and Joints, Philadelphia Lea and Febiger, 1958, p. 546. 4. Nicholas, J. A., Frieberger, R. H. and Killoran, P. J.: Double-contrast arthrography of the kneeJ. Bone Joint Surg. 52-A:203, 1970. 5. Nilsonne,
U. and Moberger, G.: Pigmented villonodular synovitis of joints, Acta. Orthop. Scand. 40:448, 1969.
and pain on extremes of full motion as the mass would snap from beneath the patella. All plain roentgenograms were normal. A pneumoarthrogram was ordered but a contrast arthrogram was done and described as normal. On July 27, 1976 an arthrotomy was performed with a preoperative diagnosis of a loose body. A small amount of straw colored synovial fluid was encountered as a 3 x 2.5 cm tumor was discovered attached to the synovium immediately above the superior aspect of the medial femoral condyle by a 1.5 cm pedicle. The immediately adjacent synovium appeared grossly hypertrophic but no other joint abnormalities were noted. A limited local synovectomy was done in removing the mass. The postoperative course was without complication. The microscopic diagnosis was pigmented villonodular synovitis (Fig. 1).
Diffuse pigmented villonodular synovitis is a relatively rare condition most commonly involving the knee joint. The localized nodular form of this condition nearly always involves the knee joint and may be responsible for presenting signs and symptoms suggesting a loose body.'-3 The following case presentation adds further documentation to the cited literature suggesting that localized villonodular synovitis be considered as an occasional cause of knee symptoms and signs suggesting a loose body.
CASE REPORT C.H.A 21-year-old black woman was first seen in the orthopedic clinic at the Martin Luther King, Jr. General Hospital on July 14, 1976 complaining of intermittent locking, swelling and pain in her right knee of one year's duration. There was no history of trauma. She was aware of a movable body about the medial aspect of her knee. On physical examination a 3 X 2.5 cm nontender mass could be palpated adjacent to the medial border of the right patella which would disappear upon pressure beneath the patella. There was a mild effusion
DISCUSSION The localized form of villonodular synovitis may present as internal derangement of the knee. Rarely is this diagnosis made preoperatively. Though the prognosis is excellent following local excision when compared with the less optimistic results associated with total synovectomy for the diffuse variety, it would seem that consideration of this entity in the differential diagnosis of internal derangement would permit the occa-
From the Martin Luther King, Jr. General Hospital, Los Angeles, California. Received: December 3, 1976. 230
Number 129 November-December, 1977
Pigmented Villonodular Synovitir
23 I
sionally encountered case to be diagnosed preoperatively. The air arthrogram is more accurate in detecting loose bodies than is arthrography utilizing contrast media.4 It is suggested that with a palpable loose body, not roentgenographically detectable in a nontrauma patient, a pneumoarthrogram may be of value in establishing a preoperative diagnosis of localized villonodular synovitis. SUMMARY A 21-year-old woman with a history of internal derangement of the knee and a palpable loose body was found to have localized villonodular synovitis at surgical exploration. REFERENCES 1. Byers,
P. D., Cotton, R. E.. Deacon, W.,
Lowy, M., Newman, P. H., Sissons, H. A. and Thomson, A. D.: The diagnosis and treatment of pigmented villonodular synovitis, J. Bone Joint Surg. 50-8:290, 1968. 2. Granowitz, S. P. and Mankin, H. J.: Localized pigmented villonodular synovitis of the knee, J. Bone Joint Surg. 49-A:122, 1967.
FIG. 1. Photomicrograph ( 2 5 0 )~. Giant cells with iron pigment visible typical of villonodular synovitis. 3. Jaffee, H. L.: Tumor and Tumorous Condi-
tions of the Bone and Joints, Philadelphia Lea and Febiger, 1958, p. 546. 4. Nicholas, J. A., Frieberger, R. H. and Killoran, P. J.: Double-contrast arthrography of the kneeJ. Bone Joint Surg. 52-A:203, 1970. 5. Nilsonne,
U. and Moberger, G.: Pigmented villonodular synovitis of joints, Acta. Orthop. Scand. 40:448, 1969.
