Dry taps and what to do about them: A pictorial essay on failed arthrocentesis of the knee

Sonographic diagnosis of an arterioarticular fistula following knee arthrocentesis

“…In addition, Roberts et al 7 found that the medial plica and a medial patella fat pad could cause difficulty with an intra-articular needle. With the supine patient, the contralateral knee may occasionally make access more limited when using the medial approach.…”

Lipoma arborescens of the knee

“…Apart from the five patients described by Hallel et al 10 all have been the subject of single case reports, 1,[3][4][5][6][7][8][9][12][13][14] some of which lacked pathological confirmation and clinical follow-up. 1,4,6,8,9,[11][12][13] Although Placeo and Tassi 18 presented a large series of cases and suggested a traumatic origin for this lesion, their series has not been accepted as lipoma arborescens because it showed reactive synovial hyperplasia overlying normal deposits of fat. 10,11 Patients with lipoma arborescens usually have longstanding, slowly progressive swelling of the involved joint, which may be associated with effusion, decreased range of movement and pain.…”

“…4,6,8,9,13 Macroscopically, lipoma arborescens has a frond-like appearance with numerous broad-based polypoid or thin papillary villi composed of fatty yellow tissue. Histologically, the villi are filled with mature adipose cells, and enlarged or congested hyperaemic capillaries may be present.…”

“…19 Two of our five patients had a history of psoriatic arthritis, and this has also been documented in another recent case report. 13 It is not clear whether diseases such as osteoarthritis, rheumatoid arthritis, and psoriatic arthritis cause lipoma arborescens, or are merely coincidental.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14] We present six cases (Table I) involving the knee, and review the literature on this unusual lesion.…”