The knotting probability is defined by the probability with which an N -step self-avoiding polygon (SAP) with a fixed type of knot appears in the configuration space. We evaluate these probabilities for some knot types on a simple cubic lattice. For the trivial knot, we find that the knotting probability decays much slower for the SAP on the cubic lattice than for continuum models of the SAP as...

Iatrogenic complications in medicine are increasing in frequency, especially in critical care environments because of the use of invasive procedures and monitoring. Although nasogastric tubes are routinely used for decompression and/or feeding of critically ill patients, the number of potential complications almost exceeds the indications for use. Knotting of small-bore feeding tubes and nasoga...

BACKGROUND Several appendiceal stump closure tecniques such as intracorporoeal-knotting, endoloop, stapler and clips are used during laparoscopic appendectomy. This study aimed to compare intracorporoeal-knotting and endoloop tecniques used to close appendiceal stump in laparoscopic appendectomy. METHODS This study included patients who underwent laparoscopic appendectomy with preliminary dia...

Catheter knotting is a rare complication of bladder catheterisation. Retention of catheter parts resulting in calculus formation is even rarer. We report a case of a vesical calculus formed over a broken and retained supra-pubic catheter which to the best of our knowledge has yet to be reported, along with three other cases of bladder catheter knotting.

Intestinal obstruction is common surgical emergency; ileosigmoid knot is a rare cause of intestinal obstruction (a loop ileum and sigmoid colon twisted around each other in a knot). We recorded a three cases in HASSAN II hospital in the last 3 years.

Though controversy exists regarding the utility of pulmonary artery catheters (PAC), their use persists in select patients. Knotting of these catheters upon insertion is a rare but serious complication. We present 2 cases of coagulopathic patients undergoing orthotopic liver transplantation complicated by PAC knotting on attempted line placement. Both knotted PAC were successfully removed nonsu...