COVID-19 outbreak at a reception centre for asylum seekers in Espoo, Finland.

Background shared accommodation may increase the risk of SARS-CoV-2 transmission. In April 2020, an increasing number of asylum seekers at a reception centre in Espoo, Finland presented with COVID-19 despite earlier implementation of preventive measures. We decided to screen the entire population of the centre for SARS-CoV-2. Methods we offered nasopharyngeal swab collection and SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) analysis to the centre's clients. Symptoms were recorded at the time of diagnostic sample collection using electronic forms and followed up for two weeks through phone interviews and a review of medical records. Findings 260 clients were screened. Of them, 96 (37%) were found positive for SARS-CoV-2 and isolated. The high attack rate prompted the local public health authority to set the other clients in quarantine for 14 days to prevent further spread. Of the positive cases, 61 (64%) reported having had symptoms at the time of the screening or one week prior. Of the 35 initially asymptomatic individuals, 12 developed symptoms during follow-up, while 23 (or 18% of all screened SARS-CoV-2 positive clients) remained asymptomatic. No widespread transmission of COVID-19 was detected after the quarantine was lifted. Interpretation in this large COVID-19 outbreak, voluntary mass screening provided valuable information about its extent and helped guide the public health response. Comprehensive quarantine and isolation measures were likely instrumental in containing the outbreak. Funding Finnish Institution for Health and Welfare, Finnish Immigration Agency, City of Espoo.

A new form of metaphyseal chondrodysplasia in two sibs: surgical treatment of tracheobronchial malacia and scoliosis.

We describe a 19-year-old male with a previously unrecognized form of disproportionate short stature, tracheobronchial malacia, and progressive scoliosis and his 28-year-old sister with the same but milder condition. The clinical characteristics were short limbs and digits and thoracolumbar scoliosis. Bone films showed progression from marked metaphyseal dysplasia of tubular bones in childhood to short and broad bones with mild dysplasia of the joints in adulthood. The vertebrae and the intervertebral plates were only mildly affected in spite of marked scoliosis. Trachea and bronchi were reinforced with surrounding acrylate mesh before surgical treatment of the scoliosis. Affected sibs of both sexes and healthy parents suggest an autosomal recessive mode of inheritance.

Influence of the modified Milwaukee brace on the dentofacial complex.

The influence of the Milwaukee brace treatment in a material of 56 patients, mean age 13.9 +/- 2.1 years, was studied. Thirteen of the patients wore monoblock and 46 did not, during the period of wearing the MW-brace, mean 0.9 years. Pre- and post-treatment cephalograms and study models were analysed. Small but significant detrimental changes were seen in about half of the 22 dentofacial variables analysed. Decreasing of the interincisors angle and the palatal vault height, and increasing of the ILs-SNL, ILs-MaxL and canine width were highly significant changes. Detrimental changes in the monoblock group occurred also but they were not as considerable as in the non-monoblock group. The influence of the five dentofacial characteristics which were analysed in more detail did not show any clear correlation to the magnitude of the change.

Cathepsin B, the lysosomal thiol proteinase of calf liver.

Cathepsin B from calf liver was obtained by a method involving preparation of a lysosomal-mitochondrial pellet and treatment of this pellet with acetone. The material was extracted with an acid buffer, pH4.0, and then precipitated from the extract with acetone. The precipitate was dissolved in phosphate buffer, pH7.4, and subjected to gel filtration on Sephadex G-200 and G-100. The cathepsin B emerged in a range of molecular weight much lower than 50000 as a well-defined component. The purity of this material was checked by electrophoresis. To obtain maximum activity the enzyme had to be activated with a chelating agent and a reducing agent (i.e. EDTA and cysteine). A number of different substrates were used. The enzyme was active for the hydrolysis of both peptide bonds and ester bonds and had approximately equal reactivity in the two cases. The pH-dependence of the hydrolysis was the same with both substrates. The binding of the substrates was half-maximal at pH4.5 and at pH6.8. A thiol group occurred in the active centre but this group ought to have a much higher pK than that found in this enzyme.

Treatment of lumbar lytic spondylolisthesis using osteoperiosteal transplants in young patients.

A series of 40 young patients with lumbar spondylolisthesis is presented. The patients were treated surgically using osteoperiosteal transplants as the fusion material. In 29 patients, the fusion was posterior and in 11 patients posterolateral. The loose posterior element was removed in eight patients in connection with fusion. The degree of slipping on admission was less than 30% in 18 patients (45%), 30 to 50% in 5 patients (12.5%), and more than half of the olisthetic vertebral body in 17 patients (42.5%). A good clinical result was obtained in 24 patients (60%), satisfactory in 11 (27.5%), and poor in 5 (12.5%). Solid union was obtained in 29 patients (72.5%), nonunion in 7 cases (17.5%), and in 4 patients (10%) the union was considered uncertain. One patient was reoperated on. The best results were obtained using posterior fusion, while the rate of nonunion was higher in the posterolateral group. The periosteum was taken from the anteromedial aspect of the tibia using a sharp chisel. The method gives clinical and radiological results comparable with those obtained using bone transplants.

Pregnancy and delivery in patients operated by the Harrington method for idiopathic scoliosis.

The course and outcome of 142 pregnancies in 146 patients operated between 1970 and 1975 by the Harrington method for idiopathic scoliosis were studied to determine the effects of scoliosis on pregnancy and childbirth and the effects of pregnancy on the remaining fused and unfused scoliotic curvatures. Occurrence of and sick leave due to low back pain during pregnancy was determined. The patients, all originally treated at the Orthopaedic Hospital of the Invalid Foundation (Orton) in Helsinki, Finland, were invited to a clinical and radiological re-examination on average 19 years following surgery. The results show that pregnancy does not significantly increase fused scoliotic curvatures nor the remaining unfused curvatures. A somewhat higher proportion of children (23%) were delivered by cesarean section than in the general population (15%; P < 0.01), but this result should only be taken as suggestive. Rates of complications of pregnancy and in labor did not differ from those in the background population. The offspring were healthy. Low back pain during pregnancy occurred in about 40% of our patients, but was severe enough to cause sick leave only in 11% of the pregnancies.

Fractures of the proximal femur in Finland in 1975.

Hospital admissions due to fractures of the proximal femur in Finland increased 50% between 1968 and 1976. In this study the established differences and results of treatment in regional and district hospitals are reviewed. From the mortality incidence and the length of hospitalisation, the results were better in regional than in district hospitals, and better for operatively than for conservatively treated patients. Of the different operative methods, the best primary results were obtained with endoprosthetic replacement and osteosynthesis with a fixed-angle nail plate.

Periosteal and perichondral grafting in reconstructive surgery.

Periosteum consists of multipotent mesodermal cells, and the influence of the environment on differentiation of cells of free periosteal grafts has been demonstrated in experimental studies. Periosteum has the capacity to form all varieties of connective tissue. The periosteum has osteogenic capacity, but it can also be used to promote cartilage formation in a chondrotrophic environment. Free periosteal grafts transplanted to the completely chondrectomized articular surfaces of patellae in experimental animals differentiated into cartilage. Joint motion appeared to be one of the chondrogenesis-promoting factors. The authors are optimistic about the potential clinical results with these types of grafts. Also, periosteal resurfacing of the metatarsal head was found to be suitable in the treatment of hallux rigidus and Freiberg's disease. Findings in growing rabbits showed that spinal fusion can be achieved with free periosteal grafts. This technique has been used to treat lumbar lytic spondylolisthesis in young patients, and the method produced clinical and radiologic results that were comparable with those obtained using bone transplants. This work indicates that some of the adverse effects of lumbar spinal fusion (e.g., postoperative spinal stenosis) can be avoided by using osteoperiosteal fusion. Also, periosteal grafting has proved useful in the treatment of thoracolumbar scoliosis. Free periosteal grafting has been used to treat congenital clefts of the maxilla and tracheal cartilage defects.