Articular lymphoscintigraphy in human knees using radiolabeled dextran.

Whereas joint lymphatics are inaccessible to conventional (oil-contrast) lymphography, articular lymphatic dysfunction can be assessed by lymphoscintigraphy (isotope lymphography). Using 99mTc-labeled dextran (molecular weight-70,000 daltons), we performed dynamic lymphoscintigraphy in 38 patients with degenerative osteoarthropathy of the knee. Comparison with the normal (contralateral knee) in 25 patients demonstrated that tracer disappeared at 24 hours more slowly from the abnormal side (86.5 +/- 3.3% retention in the abnormal joint compared with 77.1 +/- 4.6%; p less than 0.01), but accumulated more intensely in regional lymph nodes on the pathologic side (3.8 +/- 2.4% vs 1.9 +/- 0.3%; p less than 0.01). The findings suggest deranged macromolecular transport and lymphatic dysfunction in degenerative knee joint disease.