Trends in incidence and average waiting time for arthroplasty from 1998-2021: an observational study of 282,367 patients from the Scottish arthroplasty project.

BACKGROUND: Current waiting times for arthroplasty are reported as being the worst on record. This is a combination of increasing demand, the COVID-19 pandemic and longer standing shortage of capacity. The Scottish Arthroplasty Project (SAP) is a National Audit that analyses all joint replacements undertaken in the Scottish NHS and Independent Sector. The aim of this study was to investigate the long-term trend in provision and waiting time for lower limb joint replacement surgery. METHODS: All total hip replacements (THR) and total knee replacements (TKR) undertaken in NHS Scotland from 1998 to 2021 were identified. Waiting times data were analysed each year to determine the minimum, maximum, median, mean and standard deviation. RESULTS: In 1998, there were 4,224 THR and 2,898 TKR with mean (range, SD) waiting time of 159.5 days (1-1,685, 119.8) and 182.9 days (1-1,946, 130.1). The minimum waiting times were both in 2013 for 7,612 THR - 78.8 days (0-539, 46) and 7,146 TKR - 79.1 days (0-489, 43.7). The maximum waiting times recorded were in 2021 with 4,070 THR waiting 283.7 days (0-945, 215) and 3,153 TKR waiting 316.8 days (4-1,064, 217). CONCLUSIONS: This is the first robust large-scale national dataset showing trends in incidence and waiting time for THR and TKR over two decades. There was an expansion of activity with a reduction in waiting time, which peaked in 2013, followed by an increase in waiting time with a plateau and modest decline in the number of procedures.

Effect of anionic polymeric hydrogels on spermatozoa motility.

The effects of a few synthetic polymers on the motility of human spermatozoa in vitro have been studied. An alternate copolymer of styrene and maleic anhydride, poly(S-MA), poly (styrene-maleic acid), poly(S-MC), poly(hydroxy-ethyl methacrylate-methacrylic acid) copolymer, poly(HEMA-MAC), poly(HEMA) homopolymer and poly(MAC) homopolymer were chosen for this purpose. It was found that all the carboxylic acid containing polymers are strong inhibitors of the motility of spermatozoa. Poly(HEMA) did not have any inhibitory effect on the motility of spermatozoa.

PIP: This paper describes the effects of selected synthetic polymers on the motility of human spermatozoa in vitro. The authors have developed a new mehtod of male fertility control that involves the use of an anionic hydrophilic polymer which when infected into the vas deferens, is precipitated and lowers the pH in the vicinity, thus killing the spermatozoa passing through the vas deferens. The results of this experiment indicate that carboxylic acid-containing polymers are strong inhibitors of sperm motility. Almost all sperm became immotile within 15 minutes after treatment with polymer (styrene-maleic acid) (S-MC) and polymer methacrylic acid (MAC). Polymer (HEMA-MAC), a copolymer containing roughly equal ratios of hydroxyethyl methacrylate and methacrylic acid, showed inhibitory action, but it took 30 minutes for 100% immotility to be achieved. The stronger inhibition of motility observed with poly (S-MC) compared with poly (HEMA-MAC) is attributed to the presence in the former of 2 carboxylic groups on adjacent carbon atoms. It is possible that low pH environment created by ionization of carboxyl groups fixed in the polymer matrix is responsible for killing the spermatozoa. Hydrogen ion concentration is considered to be a key factor in influencing the motility, viability, and metabolism of spermatozoa. Poly (HEMA), containing only hydroxyl groups, did not have any inhibitory effect.