Mitomycin C Effect on Fibrous Adhesions of Rabbit Temporomandibular Joint

Adhesion reduction after knee surgery in a rat model by mitomycin C

The purpose of this study was to investigate the effect of Mitomycin C on reduction in intra-articular fibrotic adhesion formation after knee surgery. Twenty female Wistar Albino rats were divided into two equal study groups. After skin incision, the right knees of animals were opened through a medial parapatellar approach, and the medial and lateral sides of the femoral condyle were exposed. A partial capsulotomy and synovectomy were performed. In group I, Mitomycin C was applied in the articular cavity of rats after hemostasis. An identical volume of sterile normal saline was applied in group II, which served as controls. All rats received weekly (6 weeks) intra-articular both Mitomycin C and saline starting from the day of operation. Animals were killed at 45 days after surgery. The presence and severity of osteo-capsular adhesion was assessed with both macroscopic and microscopic adhesion scoring systems. Results of macroscopic observations showed a significant reduction in both incidence and severity of adhesions in group I compared to group II. Histologically, adhesions in group I were thinner with less collagenic fibers. Microscopic determination of adhesion formation was less in group I, and the difference between groups was statistically significant. Our results suggest that post-operative administration of Mitomycin C may be considered a promising preventive therapy for the reduction in fibro-adhesive scars and consequent stiffness after knee surgery.

Effect of mitomycin-C on post-operative adhesions in tendon surgery: an experimental study in rats

We investigated the effect of mitomycin-C on the reduction of the formation of peritendinous fibrous adhesions after tendon repair. In 20 Wistar albino rats the tendo Achillis was cut and repaired using a modified Kessler technique. The rats were divided into two equal groups. In group 1, an injection of mitomycin-C was placed between the tendon and skin of the right leg. In group 2, an identical volume of sterile normal saline was injected on the left side in a similar fashion. All the rats received mitomycin-C or saline for four weeks starting from the day of operation. The animals were killed after 30 days. The formation of peritendinous fibrous tissue, the inflammatory reaction and tendon healing were evaluated. The tensile strength of the repaired tendons was measured biomechanically. Microscopic evidence of the formation of adhesions and inflammation was less in group 1. There was no significant difference in the tensile load required to rupture the repaired tendons in the two groups. Mitomycin-C may therefore provide a simple and inexpensive means of preventing of post-operative adhesions.

Study of Wound Healing in Rats Treated with Topical and Injected Mitomycin C

Objectives:

Mitomycin C, a widely used chemotherapeutic drug, has been proposed as a potential adjuvant for the control of scar tissue in surgical wounds because of its capacity to inhibit fibroblast proliferation. The current study used a combination of topical and injected mitomycin C to slow the healing process of surgical wounds in rats.

Methods:

An experimental model of surgical wounding at the dorsum of rats was used. A total of 43 animals were subdivided into 3 groups: Control, topical mitomycin C, and a combination of topical treatment and intradermal injections of the drug at 30 and 60 days after the initial topical treatment. After 3 months, the animals were painlessly sacrificed and the surgical scars were removed for microscopic analysis.

Results:

The group that received only topical mitomycin C presented milder inflammatory signs and consequently had a less intense healing process than the control group. The group treated with a combination of both topical and injected mitomycin C presented results comparable to those of the control group.

Conclusions:

The toxic characteristics of mitomycin C were most likely responsible for the greater tissue damage that occurred when it was used in the injected form, causing increased scar tissue formation. Mitomycin C slows the healing process of surgical wounds when used topically, but causes enhanced scar tissue formation when injected.