Arthroscopic arthrolysis for flexion contracture following intraarticular reconstruction of the anterior cruciate ligament.

This article describes the surgical technique and expected results for arthroscopic arthrolysis for the treatment of flexion contracture following anterior cruciate ligament (ACL) reconstruction. The technique emphasizes a systematic approach to the surgical procedure followed by an intensive rehabilitation program. The results in 11 patients treated with this technique are reviewed. They averaged 12.6 months from the index ACL reconstruction. Despite extensive physical therapy, their mean preoperative flexion contracture was 19 degrees, mean total range of motion was 94 degrees, and mean preoperative Lysholm score was 67. At a mean follow-up of 22 months following arthrolysis and physical therapy, mean flexion contracture improved to 2 degrees, total range of motion improved to 125 degrees, and mean Lysholm score improved to 94.

Tissue-specific pharmacodynamics of 5-bromo-2'-deoxyuridine incorporation into DNA in VX2 tumor-bearing rabbits.

The thymidine analog 5-bromo-2'-deoxyuridine (BrdUrd) is felt to exert its cytotoxic effects primarily through incorporation into DNA. We have evaluated the incorporation of BrdUrd into the DNA of relevant normal tissues (bone marrow, gut mucosa, and liver) and tumor in rabbits with the VX2 tumor growing intrahepatically. Using constant i.v. infusions, steady state plasma drug concentrations ranging from 0.4 to 65.4 microM were maintained for 24 h and tissues were harvested and processed so that a sensitive gas chromatography/mass spectrometry (GC/MS) method could be used to analyze the thymine and 5-bromouracil content of hydrolyzed DNA. In all tissues, DNA incorporation showed saturating effects as plasma BrdUrd concentration was increased and, BrdUrd incorporation as a function of plasma concentration could be fitted to a Langmuir-like equation generating tissue-specific pharmacodynamic parameters: Imax for percentage thymine replacement at infinite plasma BrdUrd concentrations, and C50 for the arterial BrdUrd concentration generating incorporation that is Imax/2. At all plasma concentrations of BrdUrd the incorporation into DNA of bone marrow was greater than that observed in VX2 tumor. However, BrdUrd labeling index (with a BrdUrd monoclonal antibody) was greater in tumor than bone marrow. Thus, pharmacodynamic differences in incorporation do not result solely from cytokinetic differences between tissues. This model may prove useful in evaluating the pharmacodynamics of incorporation in studies using hepatic arterial infusion and biochemical modulation to improve selectivity.