Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits. A group of 12 skeletally mature rabbits were randomly divided into two groups. One group received subcutaneous (SQ) saline, and a second group received SQ ketotifen injections. Biomechanical data were collected at eight, ten, 16, and 24 weeks. At the time of necropsy, posterior capsule tissue was collected for histopathological and gene expression analyses (messenger RNA (mRNA) and protein).Aims
Methods
We studied the time course of micro-embolism by recording high intensity transient signals (HITS) on Doppler venous blood flow studies during a 7-day period in 57 of 63 consecutive patients after hip or knee replacement. No HITS were found before surgery, or in the non-operated leg after surgery. In the operated leg, the median number of HITS per minute showed an exponential decrease with time; a 50% reduction in the number of HITS took 72 minutes. Regardless of the duration and severity of HITS, we found no clinically apparent embolic event. Colour Doppler imaging at days 8 to 10 after operation showed a deep venous thrombosis in 17% of our patients with one thrombosis of the long saphenous vein. The presence or severity of HITS did not predict the venous thrombi. Although we found no pulmonary complications, we detected micro-emboli over a longer period after surgery than is usually reported. Spectral analysis of the Doppler venous signal is a repeatable and non-invasive monitoring technique in the post-surgical period. We failed to prove a correlation between deep venous thrombi and micro-emboli detected by this method.
