pyrophosphate and Hemarthrosis

We examined the time course of the development of hemorrhagic synovitis in response to repeated autologous blood injections into knee joints in mature dogs and the possible usefulness of joint imaging with technetium-99m pyrophosphate (Tc99m-PYP) in monitoring the early response of synovium to blood. Experimental hemarthrosis was induced in dogs by twice weekly injection of autologous blood into the knee joints. Sequential examination of the synovium at monthly intervals over a period of 12 weeks revealed early inflammatory cell infiltration and capillary neovascularization with eventual replacement of the normal fatty synovium by dense fibrous tissue. Serial Tc99m-PYP joint images demonstrated a progressive increase in isotope accumulation in the knees during the course of the study. Further isotope accumulation was observed after CO2 laser synovectomy. During the 24-week course of the entire study, no changes in joint cartilage or bone were observed by gross inspection or radiologic and light-microscopic examination. The findings indicate that the progressive proliferative, inflammatory, fibrotic changes in joint synovium associated with experimental hemarthrosis in dogs may be noninvasively and semiquantitatively assessed with the use of Tc99m-PYP scintigraphy. Evidence is also presented that the intensity of Tc99m-PYP joint accumulation (immediate static images) may not readily reflect synovial vascularity or synovial tissue mass.

Topics: Animals; Diphosphates; Dogs; Hemarthrosis; Knee Joint; Radionuclide Imaging; Synovitis; Technetium; Technetium Tc 99m Pyrophosphate

To determine the validity of a method for induction of experimental hemarthrosis in dogs and for the nuclear imaging of hemarthrosis, serial technetium-99m pyrophosphate [( 99mTc]PYP) flow and blood-pool scans were performed monthly in eight dogs who received bi-weekly injections of autologous blood into their femoro-tibial joints (also called stifle joint). In four control dogs, one joint was injected with saline while the other joint received only a sham injection. In addition, two dogs received intra-articular injections of autologous blood into their right stifle joint and saline into their left stifle joint. These dogs were studied with 99mTcO4 joint scintigraphy at monthly intervals. The dogs were periodically taken out of the study and explored surgically. Pathologic examination of synovial tissue was performed. Serial radiographs were also obtained and correlated with the scan and surgical findings. There was a striking abnormal increase in blood-pool activity of [99mTc]PYP in the treated stifle joints, commencing at the first examination after 1 mo of blood injections and continuing for the length of the study. All radiographs showed only minimal joint space widening and some soft-tissue swelling. On pathologic examination, both grossly and microscopically, there was profuse pannus formation, with intense inflammatory infiltrate replacing much of the subsynovial fat. The scintigraphic findings correlated well with these pathologic findings. This study not only validates this method for simulating hemophilic hemarthrosis but also suggests that [99mTc]PYP joint scintigraphy is a simple, and noninvasive method for monitoring the early changes in hemophilic arthropathy and is superior to pertechnetate imaging for this disease process. Instead of the previously recommended delayed bone images, we recommend, in addition, flow studies to assess joint hypervascularity and immediate static images to visualize the synovium and joint capsule.

Topics: Animals; Blood; Diphosphates; Disease Models, Animal; Dogs; Hemarthrosis; Hindlimb; Injections, Intra-Articular; Joints; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium; Technetium Tc 99m Pyrophosphate

Spontaneous haemarthrosis may occur during the evolution of articular chondrocalcinosis. It occurs mainly in older women and involves the knee in particular. The disorder may recur in the same or in different joints. A study of 11 case histories and counts of red blood corpuscles in samples of synovial fluid confirm that bleeding occurs more readily in chondrocalcinosis than in arthrosis alone. The proposed mechanism of haemarthrosis is only a hypothesis, but it is possible to imagine the onset of microcrystalline flow in a joint that is senile and affected by arthrosis. It is suspected that repeated haemarthrosis favours an oseolytic evolution in certain cases of chondrocalcinosis.

Topics: Aged; Calcium Phosphates; Chondrocalcinosis; Crystallization; Diphosphates; Female; Hemarthrosis; Humans; Inclusion Bodies; Knee Joint; Leg Injuries; Male; Middle Aged; Osteoarthritis; Osteochondritis; Osteolysis; Synovial Fluid

Topics: Adult; Age Factors; Aged; Arthritis; Calcium Phosphates; Chondrocalcinosis; Diphosphates; Female; Fever; Hemarthrosis; Hemostasis; Humans; Joint Diseases; Male; Middle Aged; Osteoarthritis; Osteochondritis; Sex Factors; Synovial Fluid; Synovial Membrane