Use of a Herbert screw for interphalangeal joint arthrodesis.

Fifty-one Herbert-screw fixation procedures were performed for interphalangeal fusion in the hand. The preoperative diagnoses included rheumatoid arthritis, degenerative arthritis, posttraumatic arthritis, and chronic mallet finger. All patients were observed until there was clinical and radiographic evidence of union. Solid osseous union occurred in all patients. Herbert screw fixation for interphalangeal arthrodesis was a simple, effective technique permitting early mobilization; complications were minimal.

Use of cross-linked bovine pericardium as a disc replacement in the rabbit temporomandibular joint.

Chemically purified bovine pericardial membrane, highly cross-linked with monomeric glutaraldehyde, was implanted in the TMJ area in ten adult rabbits in place of partially excised discs. Sham controls had the temporal aspect of the TMJ scraped with a scalpel. After 3 months, the whole TMJ area was processed for morphologic and scanning electron micrographic (SEM) evaluation. Evidence was found of the disintegration of the implanted pericardium, which was extensively infiltrated by inflammatory cells. The collagen matrix of the membrane was distended and dissociated, showing signs of degradation by its stainability with trichrome stain. It was concluded that cross-linking of a collagenous structure such as pericardium does not prevent it from being resorbed. It is suggested that the cytotoxic residues of polymeric glutaraldehyde within the implant may render the implant more resistant to cellular degradation.

Transport of beta-aminopropionitrile through intact skin or scar tissue.

A lathyrogen, [C14]aminopropionitrile (beta APN), was administered to 34 rats either in K-Y jelly or saline vehicles onto intact shaven skin or onto a healed splinted deep excision wound. The dynamics of beta APN transport and content in the skin or repair tissue was observed after 2, 5, 8, and 24 hr of topical administration. The repair tissue quickly absorbed the lathyrogen and reached maximum at the 2-hr sampling. The content of beta APN in the repair tissue was twice as high as that in K-Y jelly vehicle and remained high and stable for at least 24 hr only when beta APN was administered through a saline vehicle. The transport of beta APN through intact skin, irrespective of the vehicle tested, was slow and continuously increased. The study showed that almost 20% of the beta APN administered onto the wounded skin area was transported into the repair tissue within 2 hr. We suggest that, due to the absence of epidermal stratum corneum from the repair tissue, drugs, such as beta APN, penetrate quickly into the wound.

The sesamoids of the metacarpo-phalangeal joint of the thumb: an anatomical and clinical study.

Two unusual cases of injury to the sesamoids of the M.P. joint of the thumb are described. An anatomical dissection of the M.P. volar plate region, including the sesamoids, was undertaken to delineate the details of the sesamoids' relationship to the M.P. joint, flexor tendon, flexor tendon sheath and capsule of the joint. Histological studies were carried out to demonstrate a tendinous extension of the muscles that attach to the sesamoids.

Effect of topically applied beta-aminopropionitrile on granuloma tissue biochemistry.

The effects of the percutaneous transport of vehicles and the transport of beta-amino-propionitrile (beta APN) in vehicles were studied in rats. The bioavailability of topically administered beta APN was determined by measuring the degree of collagen cross-linking inhibition in the underlying granuloma tissue. Granulomas were induced by subcutaneous implantation of polyvinylalcohol sponges. From the 4th to 12th days postimplantation, a 20 mg/cm2 dose of beta APN fumarate was applied. Vehicles employed included dimethylsulfoxide (DMSO), urea, and occlusion. DMSO significantly enhanced the effect of beta APN in reducing the cross-linking of collagen. beta APN administered onto urea-pretreated skin and followed by occlusion in the granuloma tissue was more effective than beta APN in 30% DMSO, but only in the parameter reflecting extractibility of collagen into urea or thiocyanate solutions. The results suggest that beta APN administered topically in an appropriate vehicle penetrates the granuloma tissue and affects collagen polymerization. Though beta APN was topically administered, a systemic effect from the drug was evident, as documented by lower body weight of treated rats.