Biomedical subjects

H A Chansky

Publications and source records attributed to H A Chansky.

3 recordsLinked to original sources

PubMed1996

Pediatric soft-tissue sarcomas.

Pediatric soft-tissue sarcomas represent a relatively common problem in pediatric oncology. The evaluation of these lesions has contributed significantly to the understanding of the molecular basis of sarcomas, and the adjuvant treatment of these tumors has resulted in improved local control and significant improvements in long-term survival. The essence of successful treatment involves preoperative imaging, followed by needle biopsy, preoperative neoadjuvant chemotherapy, and well-documented surgical resection. Indications for radiation therapy and the adequacy of surgical margins remain areas of further investigation. The identification and treatment of well-defined histologic and molecular subtypes will allow further improvements in treatment decisions and clinical results.

Child↗

PubMed1994

Effect of sterilization and storage treatments on screw pullout strength in human allograft bone.

Many conflicting studies have been performed evaluating the effects of sterilization and storage treatments on the mechanical properties of allograft bone. In the current study, four right and left matched, sterile, deep-frozen, tibial pairs from human donors with an average age of 32 years were tested. One tibia from each pair served as a matched control for the opposite side. Each tibia was cut into four equal segments. One segment of each tibia underwent no treatment; the other three underwent one of the following treatments: irradiation, freeze drying, or ethylene oxide (ETO). Screw pullout tests were performed using four 3.5-mm cortical screws per segment. Sixteen screw pullout tests were performed for each allograft treatment. The freeze-dried specimens required significantly less force for screw pullout. The screw pullout force for the irradiated specimens and the ETO specimens did not significantly differ from their controls. These results indicate that freeze drying affected screw pullout strength. This method of processing should be questioned for structural allografts in which screw fixation is mandatory. The use of irradiation or ETO for sterilization may not have an adverse effect on screw pullout strength.

Biomechanical Phenomena↗

PubMed1991

The vascularity of the rotator cuff.

The major arterial supply to the rotator cuff is derived from the ascending branch of the anterior humeral circumflex artery, the acromial branch of the thoracoacromial artery, as well as the suprascapular and posterior humeral circumflex arteries. The pathogenesis of rotator cuff tears has been considered to be influenced by the microvascular supply of the rotator cuff tendons. Most cadaver studies have demonstrated a hypovascular area within the critical zone of the supraspinatus tendon. It has been suggested that this area of hypovascularity has a significant role in the attritional degeneration of the aging tendon. More recent studies of the microvascular supply to the supraspinatus tendon in symptomatic patients with impingement syndrome suggest that in the area of greatest impingement, i.e., the critical zone, there is actually hypervascularity. In contrast to the cadaver investigations, these studies seem to imply that hypervascularity or neovascularization is associated with symptomatic rotator cuff disease secondary to mechanical impingement.

Humans↗