The acute swollen knee: diagnosis and management

The acutely swollen knee is a common presentation of knee pathology in both primary care and the emergency department. The key to diagnosis and management is a thorough history and examination to determine the primary pathology, which includes inflammation, infection or a structural abnormality in the knee. The location of pain and tenderness can aid to localization of structural pathology even before radiological tests are requested, and indeed inform the investigations that should be carried out. Aspiration of an acutely swollen knee can aid diagnosis and help relieve pain. The management of the swollen knee depends on underlying pathology and can range from anti-inflammatory medication for inflammation to operative intervention for a structural abnormality.     

Diagnostic image (350). A woman with a swollen knee. Clear cell sarcoma

A 31-year-old woman presented with a slowly growing mass anterior from the right patella, due to a clear cell sarcoma.     

A man with a swollen scrotum

A 32-year-old man was referred to our hospital with a painless left-sided scrotal mass present since infancy. Physical examination showed 2 small ovoid masses in the left hemiscrotum and 1 testis on the right side. Ultrasound showed a supernumerary testis with fusion of epididymis. The diagnosis was: polyorchidism.     

A swollen leg after total hip arthroplasty

Two patients, a 71-year-old and a 59-year old woman who had undergone total hip arthroplasty, presented with pain, difficulty in walking and slow progressive unilateral leg swelling. They did not have any other physical abnormalities. Physical examination and other investigations indicated a cystic enlargement of the iliopectineal bursa causing venous obstruction of the v. femoralis. After exploration and excision of the swelling the patients recovered rapidly. Pathological examination showed a bursa with an extensive foreign body giant cell reaction, double-breaking fibrous polyethylene and a small quantity of granular metal pigment originating from the total hip prosthesis. A unilateral swelling of the leg can also be caused by deep venous thrombosis and primary lymphatic oedema or by other compressing swellings. Venous obstruction due to cystic enlargement of the iliopectineal bursa following total hip arthroplasty is only described incidentally. Treatment consists of decompression of the affected structures and if necessary revision of the polyethylene cup to avoid excessive polyethylene wear.     

A man with a swollen leg and abnormal globulins

A 72-year-old man presented with a two-week history of exertional dyspnea and nonclaudicatory pain and swelling in the right lower leg. Elevating the leg for short periods had not helped. The symptoms had begun soon after he took a nonsteroidal anti-inflammatory drug for right shoulder pain but persisted after he stopped taking the drug. His history included two-pillow orthopnea, but that had not worsened in the last year. He had not experienced chest discomfort.     

A man with a painful, swollen neck and fever

Lemierre's syndrome is a rare condition mostly secondary caused by an oropharyngeal infection with Fusobacterium necrophorum. We report a 62-year-old man with a classic case of Lemierre's syndrome, most likely caused by a diminished immunity as a result of an underlying chronic lymphatic leukemia.     

Diagnostic image (248). A girl with swollen cheeks

Mumps was diagnosed in an 11-year-old girl with bilaterally swollen cheeks. She had received mumps-measles-rubella vaccine as an infant.