The hidden effects of COVID-19 on HIV services in Zanzibar: country report.

The COVID-19 pandemic has had a major effect on HIV-related healthcare services. Zanzibar has experienced several interruptions of HIV services in the areas of testing and counselling, prevention of mother-to-child transmission of HIV, key population, care and treatment services as well due to the hospital operating at a reduced capacity and the strict visit restrictions with health care allocations to COVID 19 pandemic. The community HIV initiatives, such as index testing and ARVs medicine refills, were used to mitigate the consequences of the epidemic and can be applied in future emergencies. This report tries to reveal COVID-19's unnoticed consequences on HIV services in Zanzibar.

Customised silicone prostheses for the reconstruction of chest wall defects: technique of manufacture and final outcome.

Chest wall reconstruction with a customised silicone prosthesis in 13 patients (five patients with pectus excavatum, six Poland's syndrome and two with post-surgical chest wall deformity) is presented. An alginate impression or CT scan with three-dimensional reconstruction was used to produce the final mould from which the silicone prosthesis was fabricated. The surface of the silicone implant was roughened to reduce capsular contracture and holes were incorporated to allow for tissue integration. Twelve patients had aesthetically acceptable results after a mean of 5 years follow up. This series indicates that accurate assessment of the defect, modifications on manufacture and proper placement of the implant result in a more satisfactory final outcome.

The distal radioulnar joint as a load-bearing mechanism--a biomechanical study.

PURPOSE: A biomechanical study was performed to define the normal profiles of force transmission across the distal radioulnar joint (DRUJ) and their alteration as the result of surgical modification of the joint and its ligaments. METHODS: Twelve cadaver arms were used in this investigation. A custom-made jig was designed to hold the arm and allow axial loading of the hand. Force transmitted across the DRUJ was measured with sensor film. The axial force transmitted through the ulna and radius was measured with strain gauges mounted to the surface of each bone and the strain in the dorsal and volar distal radioulnar ligaments (DRUL) was measured with differential variable reluctance transducers. Measurements of force and strain with the DRUJ in the surgically unmodified condition were performed in various positions of forearm rotation and with sequential loads. Subsequently, the same series of measurements was performed after DRUL division and after reconstruction of the ligament. The effect of excision of the ulna head (Darrach's procedure) was also studied. RESULTS: Force varied significantly (p <.05) with the applied load and with forearm position, being greater in supination than pronation (sensor film data). Force transmitted through the ulna varied in an approximately reciprocal pattern with that of the radius. The greatest forces through the ulna occurred in supination and therefore mirrored the change in force transmission across the DRUJ. Between 32% and 34%, respectively, of the applied load (5-10 kg) was transmitted through the ulna and the remainder was transmitted through the radius (strain gauge data). Division of either the volar or the dorsal DRUL tended to increase the force transmitted across the DRUJ (p =.09), and reconstruction of the disrupted DRUL restored the force pattern toward the previous values (not significant) (differential variable reluctance transducer data). Excision of the ulna head disrupted the force transmission profiles, producing the biomechanical equivalent of a 1-bone forearm. Only 1.8% and 2.7% of the applied force (10 kg and 5 kg), respectively, was transmitted through the ulna (strain gauge data only). CONCLUSIONS: The data show consistent and characteristic force transmission profiles across the DRUJ and through both ulna and radius. The joint is important in the transmission of load and its anatomic integrity should be respected in surgical procedures if normal biomechanics are to be preserved.

The pulley system of the thumb: anatomic and biomechanical study.

To examine the precise conformation of the annular and oblique pulleys of the thumb flexor sheath, anatomic dissections were undertaken on 14 hands. In all specimens a distinct pulley was found between the A1 and oblique pulleys. This is named the variable annular pulley or Av pulley. There appear to be 3 discrete forms of this pulley designated type I to III. The biomechanical study was done on 8 limbs by using linear strain transduction techniques. The analysis showed that the strain in the oblique pulley was greater in extension than in flexion of the thumb. This statement remains true even after division of either the A1 or Av pulley and after section of both pulleys. The oblique pulley does not prevent bowstringing of the flexor pollicis longus when A1 and Av pulleys have been sectioned. These studies challenge current concepts of both the anatomy and mechanics of the thumb pulley system with implications for clinical procedures such as trigger thumb release and pulley reconstruction.