|Year : 2015 | Volume
| Issue : 2 | Page : 204-206
Synovial chondromatosis of the knee joint in infant: A case report and literature review
Department of Orthopedic Surgery, King Saud University, Riyadh, Saudi Arabia
|Date of Web Publication||6-May-2015|
Department of Orthopedic Surgery, King Saud University, Riyadh
Synovial chondromatosis is an uncommon benign disorder that is most often occurring in adults. It is an exceedingly rare condition in children. We are describing an unreported cause of knee swelling in an infant. Clinical and radiological evaluation revealed that the symptoms were due to a synovial chondromatosis of the knee joint. To the best of our knowledge, this is the first report describing a knee synovial chondromatosis in an infant patient. Synovial chondromatosis should be included in the differential diagnosis of knee swelling during infancy. Greater physician awareness of such condition together with a high index of suspicion is crucial for diagnosis.
عضرلا لافطلأا دنع ةبكرلا لصفم يف يليلزلا يفورضغلا مرولا
بيصي ام اردانو ,نيغلابلا بيصي ام ابلاغو عئاش ريغ ابارطضا يليلزلا يفورضغلا مرولا ّدعي فشكلا رهظأ دقو .عضرلا لافطلأا دحأ ىدل ةبكرل مروت ةلاح فصي ريرقتلا اذهو .لافطلأا بسحو ةبكرلا لصفمل يليلزلا يفورضغلا مرولا ببسب تناك ضارعلأا نأ يعاعشلإاو يريرسلا ىدل ةبكرلا لصفم يف يليلزلا يفورضغلا مرولا فصي يذلا ديحولا وه ريرقتلا اذه نأ ،انملع صيخشت يف يليلزلا يفورضغلا مرولا جردي نأ يغبني هنا ريرقتلا جئاتن نم تناك و .عضرلا ىضرملا ةجرد عافترا عم ةلاحلا هذهب جلاعملا بيبطلل ريبكلا يعولا دعيو .ةلوفطلا ةلحرم للاخ ةبكرلا مروتضرملا صيخشتل امساح ارمأ هابتشلاا
Keywords: Infant, knee, synovial chondromatosis
|How to cite this article:|
Al-Khawashki H. Synovial chondromatosis of the knee joint in infant: A case report and literature review. Saudi J Sports Med 2015;15:204-6
|How to cite this URL:|
Al-Khawashki H. Synovial chondromatosis of the knee joint in infant: A case report and literature review. Saudi J Sports Med [serial online] 2015 [cited 2021 Sep 17];15:204-6. Available from: https://www.sjosm.org/text.asp?2015/15/2/204/146353
| Introduction|| |
Synovial chondromatosis (also known as synovial osteochondromatosis or synovial chondrometaplasia) is an uncommon benign disorder. It is marked by the metaplastic proliferation of multiple cartilaginous nodules in the synovial membrane of the joints, bursae, or tendon sheaths.  It, usually, occurs in patients between 30 and 50 years of age with a male to female ratio of 2:1. It is almost invariably monoarticular; rarely, multiple joints may be affected. Synovial chondromatosis is extremely rare in pediatric patients. ,,,,,,,
We are describing an unreported cause of knee swelling in an infant that turned out to be a synovial chondromatosis. To the best of our knowledge, this is the first report that describing a knee synovial chondromatosis in an infant. The patient's family agreed that the date concerning the case would be submitted for publication and was approved by the Institutional Review Board.
| Case report|| |
A 16-month-old boy presented with left knee swelling. The swelling started 2 months prior to the presentation without history of antecedent trauma. Initially, the knee swelling coincides with an attack of fever for 2 days that resolved spontaneously with antipyretics prescribed by the general pediatrician. The family also noticed progressive limping while walking.
Clinical examination upon presentation revealed healthy and afebrile child who was walking on the tip toes of the left foot with a limping gait. Left knee examination revealed swollen knee with effusion, clicking sensation during motion,and flexion deformity of 20°; otherwise the knee flexes to full [Figure 1]. There were no palpable lymph nodes and examination of the hips; ankles and back was within normal.
Laboratory workup revealed a normal white blood cell count: 7000/mm (normal; 4500-10,000/mm), a normal C-reactive protein: 1.0 mg/L (normal; 0-4 mg/L), and mildly elevated erythrocyte sedimentation rate count: 22 mm/h (normal; < 20 mm/h).
In view of the persistent patient symptoms and failure of medical treatment, we proceeded to radiological investigations. Plain radiographs of both knees showed a soft tissue swelling of the left knee. However, no calcified nodules identified [Figure 2]. To further delineate the swelling, a magnetic resonance imaging was also performed. It demonstrated a cartilaginous lobular appearance consistent with chondromatosis [Figure 2].
|Figure 2: (a) Anteroposterior and lateral views of both knees plain radiographs showing the knee swelling on the left side (arrow). (b) Coronal and axial magnetic resonance imaging views demonstrating the left knee|
synovial chondromatosis (arrow)
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Based on clinical and radiological findings, a provisional diagnosis of synovial chondromatosis versus a synovial tumor was suspected, and the decision was to proceed for excision and subtotal synovectomy. At the time of the procedure, a medial parapatellar arthrotomy was performed. On incision, a clear, straw-colored synovial fluid was obtained in addition to wondering grape-like grayish soft nodular masses [Figure 3]. Histopathological examination of the excised lesion confirmed the diagnosis of synovial chondromatosis.
Postoperatively, the patient had complete resolution of knee swelling within 3 months. At the most recent 1-year follow-up, the patient was doing well, and there were no signs of local recurrence.
| Discussion|| |
The differential diagnosis of knee swelling in an infant is broad. Infection, inflammation, trauma, and child abuse are established, well-reported causes of such presentation. Keeping a high index of suspicion for synovial chondromatosis was mandatory for diagnosis in the presented case.
Synovial chondromatosis is, usually, symptomatic depending on its location and severity. Occasionally, it occurs in the bursa overlying an osteochondroma. Pain, clicking, swelling and limited range of motion are the mainstay symptoms. In our case, knee swelling was the presenting symptom. Natural history is, usually, self-limited, but the process can damage the joint if left untreated. Less than adequate removal of chondromatosis nodules should be avoided as it may increase the risk for local recurrence. 
In terms of radiological and pathological findings, conditions such as pigmented villonodular synovitis, synovial hemangioma, synovial chondrosarcoma, secondary chondromatosis, and lipoma arborescens can mimic synovial chondromatosis and should be differentiated. 
There are few reported cases of synovial chondromatosis in pediatrics. Most of the cases reported after the age of 10 years. Gottschalk et al. reported a case of synovial chodromatosis involving the thumb in a 13-year-old girl.  Similarly, Narasimhan et al. reported an elbow synovial chondromatosis in an 11-year-old girl.  Kirchhoff et al. described an extremely rare presentation of synovial chondromatosis in a child affecting the sheath of the long head of biceps tendon. 
Reports of knee synovial chondromatosis similar to the current case have been described, however; in these reports, it occurred during childhood beyond the infancy period. ,, Based on a literature search, only one case of synovial chondromatosis in a 2-year-old child has been reported.  In that report, it affected the hip joint. This contrasted with the synovial chondromatosis presented here, which affected the knee joint.
| Conclusion|| |
Synovial chondromatosis could happen in infancy. It is rare and possibly misdiagnosed condition. Physicians should be aware of the possibility of this lesion in patients with unexplained symptoms. High index of suspicion together with a sufficient imaging work up are crucial for diagnosis.
| Acknowledgment|| |
We would like to thank Professor Mamoun Kremli for allowing us to publish his case.
| References|| |
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[Figure 1], [Figure 2], [Figure 3]