Effectiveness of inactivated COVID-19 vaccine CoronaVac in children aged less than 3 years old during Omicron wave in Hong Kong

The COVID-19 pandemic has affected people of all ages worldwide. However, there is still no information on the vaccine effectiveness (VE) of inactivated COVID-19 vaccines in children aged less than 3 years old. This study highlighted that 2 doses of CoronaVac were effective in preventing COVID-19, with a VE of 83.1 %.

Dynamics of childhood obesity in Hong Kong throughout the COVID-19 pandemic before and after the school closures: a 3-year longitudinal study

OBJECTIVE

This study is to evaluate if there is any difference in the balance between incidence of and remission from overweight/obesity in Hong Kong school-age children before and during the COVID-19 pandemic over three years.

METHODS

This is a retrospective longitudinal study that involved children aged 6-16 years from a database of the School Physical Fitness Award Scheme.

RESULTS

2765 students were longitudinally followed up for two years. The prevalence of childhood overweight/obesity was increased between the 2019 and 2021 academic years (P < 0.001). During the COVID-19 pandemic, the rate of obesity remission significantly reduced by 7.9 % (P = 0.003), at a background of a plateau of obesity among children and adolescents.

CONCLUSIONS

Our study provides evidence on the impact of school closure and home confinement as a standard infection control measure for the prevention of COVID-19, which are likely to break the balance between incidence of and remission from childhood obesity.

Reconstruction of a fatty acid synthesis cycle from acyl carrier protein and cofactor structural snapshots

Fatty acids (FAs) play a central metabolic role in living cells as constituents of membranes, cellular energy reserves, and second messenger precursors. A 2.6 MDa FA synthase (FAS), where the enzymatic reactions and structures are known, is responsible for FA biosynthesis in yeast. Essential in the yeast FAS catalytic cycle is the acyl carrier protein (ACP) that actively shuttles substrates, biosynthetic intermediates, and products from one active site to another. We resolve the S. cerevisiae FAS structure at 1.9 Å, elucidating cofactors and water networks involved in their recognition. Structural snapshots of ACP domains bound to various enzymatic domains allow the reconstruction of a full yeast FA biosynthesis cycle. The structural information suggests that each FAS functional unit could accommodate exogenous proteins to incorporate various enzymatic activities, and we show proof-of-concept experiments where ectopic proteins are used to modulate FAS product profiles.

COVID-19 vaccines versus pediatric hospitalization

Vaccine effectiveness of BNT162b2 and CoronaVac against COVID-19-associated hospitalization and moderate-to-severe disease due to SARS-CoV-2 Omicron BA.2 is studied from the 1.36 million doses administered to 766,601 of 953,400 children aged 3-11 years and adolescents aged 12-18 years in Hong Kong as of April 2022. These vaccines confer substantial protection.

Mental health & maltreatment risk of children with special educational needs during COVID-19

BACKGROUND

Children with special educational needs (SEN) are more vulnerable during the COVID-19 pandemic with risk of poor mental wellbeing and child maltreatment.

OBJECTIVE

To examine the impact of COVID-19 on the mental health of children with SEN and their maltreatment risk.

PARTICIPANTS AND SETTING

417 children with SEN studying at special schools and 25,427 children with typical development (TD) studying at mainstream schools completed an online survey in April 2020 in Hong Kong during school closures due to COVID-19.

METHOD

Emotional/behavioural difficulties, quality of life and parental stress of children with SEN were compared with typically developed children using mixed effect model. Linear regression analyses were performed to explore factors associated with child emotional/behavioural difficulties and parental stress during the pandemic. Chi-square test was performed to detect the differences in maltreatment risk before and during COVID-19.

RESULTS

Children with SEN had significantly poorer overall quality of life (68.05 vs 80.65, p < 0.01). 23.5% of children had at least one episode of severe physical assault and 1.9% experienced very severe physical assault during COVID-19. Rates of physical assault increased significantly (59.8% vs. 71.2% p < 0.001) while children with mental disorders had increased risk of severe physical assault comparing to those without mental disorders (RR = 1.58, ꭓ² = 5.19 p = 0.023).

CONCLUSION

Children with SEN had poorer mental health than typically developed children during the COVID-19 pandemic. Maltreatment risk for children with SEN is higher in comparison to pre-COVID-19 era. Surveillance of child maltreatment, continuity of medical and rehabilitation care to support children with SEN are essential during a disease pandemic.

An anti-inflammatory and anti-fibrotic proprietary Chinese medicine nasal spray designated as Allergic Rhinitis Nose Drops (ARND) with potential to prevent SARS-CoV-2 coronavirus infection by targeting RBD (Delta)- angiotensin converting enzyme 2 (ACE2) binding

BACKGROUND

Since the outbreak of COVID-19 has resulted in over 313,000,000 confirmed cases of infection and over 5,500,000 deaths, substantial research work has been conducted to discover agents/ vaccines against COVID-19. Undesired adverse effects were observed in clinical practice and common vaccines do not protect the nasal tissue. An increasing volume of direct evidence based on clinical studies of traditional Chinese medicines (TCM) in the treatment of COVID-19 has been reported. However, the safe anti-inflammatory and anti-fibrotic proprietary Chinese medicines nasal spray, designated as Allergic Rhinitis Nose Drops (ARND), and its potential of re-purposing for suppressing viral infection via SARS-CoV-2 RBD (Delta)- angiotensin converting enzyme 2 (ACE2) binding have not been elucidated.

PURPOSE

To characterize ARND as a potential SARS-CoV-2 entry inhibitor for its possible preventive application in anti-virus hygienic agent.

METHODS

Network pharmacology analysis of ARND was adopted to asacertain gene targets which were commonly affected by COVID-19. The inhibitory effect of ARND on viral infection was determined by an in vitro pseudovirus assay. Furthermore, ARND was confirmed to have a strong binding affinity with ACE2 and SARS-CoV-2 spike-RBD (Delta) by ELISA. Finally, inflammatory and fibrotic cell models were used in conjunction in this study.

RESULTS

The results suggested ARND not only inhibited pseudovirus infection and undermined the binding affinity between ACE2 and the Spike protein (Delta), but also attenuated the inflammatory response upon infection and may lead to a better prognosis with a lower risk of pulmonary fibrosis. The data in this study also provide a basis for further development of ARND as an antiviral hygienic product and further investigations on ARND in the live virus, in vivo and COVID-19 patients. ARND holds promise for use in the current COVID-19 outbreak as well as in future pandemics.

CONCLUSION

ARND could be considered as a safe anti-SARS-CoV-2 agent with potential to prevent SARS-CoV-2 coronavirus infection.

A fluorescent probe for STED microscopy to study NIP-specific B cells

We have developed a series of monovalent fluorophore-conjugated affinity probes based on the hapten 3-nitro-4-hydroxy-5-iodophenylacetyl (NIP), which is widely used as a model antigen to study B lymphocytes and the functional principles of B cell antigen receptors (BCRs). We successfully used them in flow-cytometry, confocal and super-resolution microscopy techniques.

Brain Microstructural Changes Associated With Neurocognitive Outcome in Intracranial Germ Cell Tumor Survivors

Background

Childhood intracranial germ cell tumor (GCT) survivors are prone to radiotherapy-related neurotoxicity, which can lead to neurocognitive dysfunctions. Diffusion kurtosis imaging (DKI) is a diffusion MRI technique that is sensitive to brain microstructural changes. This study aimed to investigate the association between DKI metrics versus cognitive and functional outcomes of childhood intracranial GCT survivors.

Methods

DKI was performed on childhood intracranial GCT survivors (n = 20) who had received cranial radiotherapy, and age and gender-matched healthy control subjects (n = 14). Neurocognitive assessment was performed using the Hong Kong Wechsler Intelligence Scales, and functional assessment was performed using the Lansky/Karnofsky performance scales (KPS). Survivors and healthy controls were compared using mixed effects model. Multiple regression analyses were performed to determine the effects of microstructural brain changes of the whole brain as well as the association between IQ and Karnofsky scores and the thereof.

Results

The mean Intelligence Quotient (IQ) of GCT survivors was 91.7 (95% CI 84.5 – 98.8), which was below the age-specific normative expected mean IQ (P = 0.013). The mean KPS score of GCT survivors was 85.5, which was significantly lower than that of controls (P < 0.001). Cognitive impairments were significantly associated with the presence of microstructural changes in white and grey matter, whereas functional impairments were mostly associated with microstructural changes in white matter. There were significant correlations between IQ versus the mean diffusivity (MD) and mean kurtosis (MK) of specific white matter regions. The IQ scores were negatively correlated with the MD of extensive grey matter regions.

Conclusion

Our study identified vulnerable brain regions whose microstructural changes in white and grey matter were significantly associated with impaired cognitive and physical functioning in survivors of pediatric intracranial GCT.

A hybrid platform featuring nanomagnetic ligand fishing for discovering COX-2 selective inhibitors from aerial part of Saussurea laniceps Hand.-Mazz

ETHNOPHARMACOLOGICAL RELEVANCE

Saussurea laniceps Hand.-Mazz. (Compositae) is a representative "snow lotus" herb well known in Chinese folk medicine to treat inflammation-related diseases such as arthritis. S. laniceps (SL) shows anti-inflammatory and analgesic potencies and contains various constituents potentially with cyclooxygenase-2 (COX-2) selective inhibition. The herb is a valuable source of natural alternatives to synthetic COX-2 selective nonsteroidal anti-inflammatory drugs, a common medication for rheumatoid arthritis (RA) and osteoarthritis (OA) reported with serious cardiovascular side effects.

AIM OF THE STUDY

Based on an innovative drug screening platform, this study aimed to discover safe, effective COX-2 selective inhibitors from SL.

MATERIALS AND METHODS

An enzyme-anchored nanomagnetic fishing assay was developed to separate COX-2 ligands from SL. Cell and animal models of cardiomyocytes, lipopolysaccharide-stimulated macrophages, rat adjuvant-induced arthritis, and anterior cruciate ligament transection-induced OA rats, were adopted to screen the single/combined ligands regarding toxicity and bioactivity levels. Molecular docking was employed to unravel binding mechanisms of the ligands towards COX-1 and COX-2.

RESULTS

Four COX-2 selective compounds were separated from SL using optimized COX-2-functionalized magnetic nanoparticles. All the four ligands were proved with evidently lower cardiotoxicity both in vitro and in vivo than celecoxib, a known COX-2 selective inhibitor. Two ligands, scopoletin and syringin, exhibited potent anti-arthritic activities in rat models of RA and OA by alleviating clinical statuses, immune responses, and joint pathological features; their optimum combination ratio was discovered with stronger remedial effects on rat OA than single administrations. The COX-1/2 binding modes of the two phytochemicals contributed to explain their cardiac safety and therapeutic performances.

CONCLUSIONS

The screened chemicals are promising to be developed as COX-2 selective inhibitors as part of treating RA and OA. The hybrid strategy for discovering therapeutic agents from SL is shown here to be efficient; it should be equally valuable for finding other active chemicals in other natural sources.

Prediction of spontaneous preterm birth by cervical length in the first trimester of pregnancy: Comparison of two measurement methods

INTRODUCTION

Our objectives were to compare the single-line and two-line methods of cervical length measurement in the first trimester of pregnancy and to evaluate the potential value of the first trimester cervical length measured by the two methods in predicting spontaneous preterm birth.

MATERIAL AND METHODS

This was a prospective study in singleton pregnancies at 11+0 to 13+6  weeks of gestation. Cervical length was measured by two methods: (i) a linear distance between the two ends of the glandular area around the endocervical canal (single-line method) and (ii) a sum of a linear distance from the internal os to the greatest cervical curvature and a linear distance from this point of the cervix to the external os (two-line method). The screening performance of the first trimester cervical length measured by the two different methods for the prediction of spontaneous preterm delivery was assessed by receiver-operating characteristics (ROC) curve analysis. The areas under the ROC (AUROC) were compared by De Long test.

RESULTS

A total of 1484 consecutive singleton pregnancies were included in this study. Spontaneous preterm delivery at <37 and <32 weeks occurred in 75 cases (5.1%) and 12 cases (0.8%), respectively. The median cervical length measured by the single-line method was significantly shorter than that by the two-line method (33.5 vs 36.5 mm, p < .001). Compared with the term delivery group, the median cervical length measured by the two-line method was shorter in women with spontaneous delivery at <32 weeks of gestation (36.5 vs 33.6 mm, p < .01). No significant difference in the median cervical length measured by the single-line method was detected between the spontaneous preterm delivery and term delivery groups. Receiver-operating-characteristic curves demonstrated that cervical length measured by the two-line method achieved better performance in predicting spontaneous delivery at <32 weeks compared with the single-line method (AUROC: 0.72 vs 0.61, p < .01).

CONCLUSIONS

We have demonstrated that the first trimester cervical length, measured by the two-line approach, holds promise as a potential screening tool for early spontaneous preterm delivery.

QOL-25. MICROSTRUCTURAL BRAIN CHANGES ASSOCIATED WITH NEUROCOGNITIVE AND FUNCTIONAL OUTCOMES OF INTRACRANIAL GERM CELL TUMUOR SURVIVORS – A DIFFUSIONAL KURTOSIS IMAGING STUDY

BACKGROUND

Childhood intracranial germ cell tumour (iGCT) survivors are prone to radiotherapy-related neurotoxicity which can lead to neurocognitive dysfunction. Diffusion kurtosis imaging (DKI) is a MRI technique that quantifies microstructural changes in the grey and white matter of the brain. This study aims to investigate the associations between MR-DKI metrics, the cognitive and functional outcomes of childhood iGCT survivors.

METHOD

20 childhood iGCT survivors who had received cranial radiotherapy were recruited. DKI parameters were determined for iGCT survivors and 18 control subjects. Neurocognitive assessment using the Hong Kong Wechsler Intelligence Scales for Children (HKWISC)/ Wechsler Adult Intelligence Scale – Revised (WAIS-R) and functional assessment using the Lansky/ Karnofsky performance scales were performed for GCT survivors.

RESULTS

There were significant negative correlation between the IQ scores and the mean diffusivity (MD) in multiple white matter regions of iGCT survivors including: anterior limb of internal capsule, superior fronto-occipital fasciculus, anterior corona radiata, uncinate fasciculus, cingulum and hippocampus. Mean kurtosis (MK) values of the superior fronto-occipital fasciculus were positively correlated with IQ scores. For grey matter, the MD of the olfactory, insula, caudate, heschl gyrus, parahippocampal gyrus, hippocampus, anterior cingulum, frontal inferior operculum, middle and superior temporal gyrus, middle and superior frontal orbital gyri, cuneus and precentral gyrus were negatively correlated with IQ scores. Most of the microstructural changes with associated functional impairment were white matter regions.

CONCLUSION

Our study identified vulnerable brain regions with significant white and grey matter microstructural changes that were associated with impaired cognitive function or deficits in physical functioning.

Aggregation-induced emissive nanoparticles for fluorescence signaling in a low cost paper-based immunoassay

Low cost paper based immunoassays are receiving interest due to their fast performance and small amounts of biomolecules needed for developing an immunoassay complex. In this work aggregation-induced emissive (AIE) nanoparticles, obtained from a diastereoisomeric mixture of 1,2-di-(4-hydroxyphenyl)-1,2-diphenylethene (TPEDH) in a one-step top-down method, are characterized through Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Zeta potential. By measuring the Zeta potential before and after labeling the nanoparticles with antibodies we demonstrate that the colloidal system is stable in a wide pH-range. The AIE-active nanoparticles are deposited on chitosan and glutaraldehyde modified paper pads overcoming the common aggregation-caused quenching (ACQ) effect. Analyte concentrations from 1000ng and below are applied in a model immunocomplex using Goat anti-Rabbit IgG and Rabbit IgG. In the range of 7.81ng-250ng, linear trends with a high R(2) are observed, which leads to a strong increase of the blue fluorescence from the TPEDH nanoparticles.

Subungual squamous cell carcinoma: report of 2 cases

Subungual squamous cell carcinoma (SCC) is a rare malignant tumor with an indolent course. Its etiology is unknown. It often involves the distal phalanx of the thumb or the index finger, and often presents as a chronic ulcer that is commonly misdiagnosed as chronic paronychia, pyogenic granuloma or verruca vulgaris. Approximately 150 cases of subungual SCC, including one in a Taiwanese patient, have been reported. Here, we report two cases of subungual SCC presenting as a chronic ulcer of the nail bed refractory to antibiotic treatment. One case involved the right thumb, while the other involved the right index finger. Radiographs of both cases showed an osteolytic bone lesion involving the distal phalanx. Excision biopsy revealed SCC in both cases. Both patients received amputation of the involved distal phalanx and showed no signs of reoccurrence during 5 years of follow-up. These findings suggest that all recalcitrant ulcers of the nail bed should be biopsied to facilitate early diagnosis and treatment of subungual SCC.

Articular cartilage lesions of the knee following immobilisation or destabilisation for 6 or 12 weeks in rabbits

Eighty mature female New Zealand White rabbits were sacrificed 6 or 12 weeks after either section of the medial collateral and the anterior cruciate ligaments with removal of the anterior third of the medial meniscus of one knee, or immobilisation of one knee, using the contralateral non-treated knee as the control. The area of degenerated joint surface of the distal femur, and water and proteoglycan content were measured, and the articular cartilage stained using haematoxylin and eosin and safranin O. Destabilisation resulted in a significantly larger time-dependent degenerated joint surface area. Water content significantly increased after 6 weeks with no significant differences between immobilisation and destabilisation. Destabilisation resulted in a significantly greater decrease in proteoglycan content. At 12 weeks, the control knees of the animals undergoing destabilisation showed significant degenerative changes. There were more extensive lesions in destabilisation, while 6 weeks of immobilisation produced moderate degenerative joint disease.

Regional nerve block for total knee arthroplasty

Femoral and sciatic nerve blocks have been used occasionally for unilateral total knee arthroplasty (TKA). In order to evaluate the effectiveness of this technique, combined femoral 3-in-1 and sciatic nerve blocks were performed in 20 cases of TKA, by the same surgeon. This surgeon also performed unilateral TKA under spinal anesthesia in another 20 cases. The anesthetic effectiveness of the two types of anesthesia was compared in terms of the time needed to complete the surgery, amount of intraoperative blood loss, and time interval until the first dose of analgesic. The results showed that the two types of anesthesia had comparable anesthetic effects. Ten of the 20 patients who had spinal anesthesia complained of postoperative urinary retention, while none of those who had nerve block had this complaint. Neither group experienced postpunctural headache, neurovascular damage, or drug-over-dose toxicity. We conclude that combined femoral 3-in-1 and sciatic nerve block is an effective anesthetic alternative for unilateral TKA.

Treatment of congenital pseudarthrosis of the tibia with the Ilizarov method

Congenital pseudarthrosis of the tibia (CPT) is a difficult orthopedic problem. Many modalities of treatment have been used but none provide comprehensive treatment with highly satisfactory results. We reviewed the surgical management and results of eight consecutive patients with CPT treated with the Ilizarov technique for nonunion, angulation, leg length discrepancy and valgus ankle between 1988 and 1992. The median age at the time of Ilizarov treatment was 1.8 years (range, 0.4-20.1 yr). Primary union at the pseudarthrosis site was achieved in five of the eight patients. After a median follow-up period of 5.2 years (range, 3.0-6.2 yr), final union at the pseudarthrosis site was achieved in seven of the eight patients (union rate, 87.5%). However, nonunion persisted at the distraction site in one patient. In the six patients who achieved union and functional recovery, the median number of total surgeries was four; there were two residual deformities. Leg length discrepancy was corrected in these six patients to less than 1.7 cm. Six out of the eight patients were satisfied with the results. In general, the treatment course was lengthy with numerous complications, especially in young children. The Ilizarov technique, with its ring design, simultaneously addresses several problems associated with CPT, and may provide a comprehensive treatment for CPT with promising results. Combination treatment with other methods is necessary.

Resurfacing of thumb-pulp loss with a heterodigital neurovascular island flap using a nerve disconnection/reconnection technique

The problems of late deterioration of sensation and a "double sensibility" phenomenon, either in the thumb or donor finger, are a known deficiency of the conventional heterodigital neurovascular island flap. This is probably related to unsatisfactory cortical reorientation following flap transfer. To obviate this problem, the authors have used a disconnection/reconnection technique for heterodigital island flaps in 17 patients, to resurface defects in the skin of the thumb. All patients were followed-up for 1 year, while 15 were followed-up for 2 years or more. There were no flap complications or failures, and the length of the thumb tip was preserved in all cases. The classic two-point discrimination was less than 6 mm in eight of these patients, and the remaining nine patients had two-point discrimination of between 6 and 8 mm. This technique was found to provide sensitive, supple, and well-vascularized skin with proper cortical representation, to replace the loss of the tactile pump of the thumb tip in one operative stage.

Subcutaneous ("inverted") verrucous carcinoma with bone invasion

Verrucous carcinoma (VC) is a low-grade cutaneous squamous carcinoma which often presents on the foot where it is known as carcinoma cuniculatum. Three cases of VC on the buttock have previously been documented. We describe a highly unusual example of VC involving the buttock with extensive iliac bone erosion, and with the apparently unique feature of being totally subcutaneous.

Prevention of potential fracture between two implants using interlocking bipolar cut short GK nail and Enders nail

A technique to prevent a potential fracture occurring between the distal end of a cementless hip prosthesis and the proximal end of a dynamic compression screw (DCS) is described. The method involves bridging the two implants using a bipolar shortened femoral nail, which is further improved by filling the gap between the stem and the femoral nail with an Enders nail. The distal connection is secured by placing the distal locking screw of the femoral nail through the distal femoral plate of the dynamic compression plate first before locking the nail to the distal femur. Further stabilisation and promotion of healing at the distal femur were achieved using cement and bone graft.

Ender nailing for ipsilateral femoral shaft fractures after Austin-Moore hemiarthroplasty

BACKGROUND

The management of ipsilateral femoral shaft fractures after hemiarthroplasty is controversial.

METHODS

Fifteen patients (average age 82.4 +/- 8 years) with ipsilateral femoral shaft fractures after uncemented hemiarthroplasty were treated by closed reduction and Ender nailing. Under radiographic control, closed reduction was attempted. If not possible, cerclage of the shaft fracture was accomplished through a limited lateral approach. Ender nails were then inserted well past the tip of the stem of the prosthesis.

RESULTS

There were a superficial wound infection and a deep vein thrombosis. At 6 months, five patients had died, and backing out of the nails necessitated removal in one patient. At 1 year, nine patients were still alive. Of these, seven were able to walk with aids. At 2 years, seven patients were still alive and were walking with aids. Two patients presented shortening of more than 1.5 cm of the operated femur. After an average of 5 years, 11 patients were dead, two were still walking, and two were bedridden.

CONCLUSIONS

The technique described is an option in the treatment of fractures of the ipsilateral femoral shaft after uncemented hemiarthroplasty.

False aneurysm with median nerve palsy after iatrogenic brachial artery puncture

We report on a case in which a patient on oral anticoagulation for her aortic valve replacement, with an International Normalised Ratio of 2.13, developed a false aneurysm of the brachial artery after a routine arterial puncture, despite direct pressure to the aspiration site. The false aneurysm was complicated by the development of median nerve palsy.

Multiple chop wounds in Hong Kong. An epidemiological study of an unusual injury

Knife injuries can be classified into stabbing injuries and multiple laceration or multiple chops, the latter being much more common in Chinese communities. It is the mark of criminal gang attacks with their tendency to use long knives and choppers rather than guns. The intention is often to wound rather than kill. A survey of 89 cases revealed that 90% of the victims are men, with a mean age of 27 years; 75% was admitted to the hospital at night, and in 78% of the cases the assailants were persons unknown, or so we were told by the victims. The reasons for the attacks were also not given. Most of the women victims were assaulted by their spouse. Some 74% of the patients suffered three to six lacerations; 62% of the injuries were on the extensor surfaces of the upper limbs, while the hand and the back of the trunk were also common sites. The type of management differs from that for stabbing injuries. There were no fatalities, and less than half of the patients required blood transfusion. The average hospital stay was 6.2 days. The morbidity of these injuries involves damaged tendons and nerves.

Cystic tuberculosis of the bone mimicking osteogenic sarcoma

Hong Kong has a relatively high incidence of tuberculosis in comparison with other developed cities, possibly due to the influx of mainland Chinese immigrants and Vietnamese boat people. However, primary, solitary cystic tuberculous infection of the bone is rare and few cases have been reported. Radiological appearances of this disease can mimic several bone conditions, including bone cyst, osteoblastoma and even osteosarcoma. We report on a case of a healthy fifteen-year-old who presented with swelling to the left elbow; biopsy confirmed this as cystic tuberculosis of the bone.

The second case of Paget's disease (osteitis deformans) in a Chinese lady

Paget's disease of the bone is extremely rare in the Chinese population. We report a case of a 91-year-old female patient who presented with a leg ulcer after an injury. On examination, she was incidentally noted to have bowing of the tibia and facial features suggestive of Paget's disease which was later confirmed with plain radiograph. An extensive search of the international literature over the last thirty years, including the use of Medline, has revealed only one other case report of Paget's disease in a Chinese patient in Thailand.

Chondromyxoid fibroma-like osteosarcoma: a distinct variant of low-grade osteosarcoma

Chondromyxoid fibroma-like osteosarcoma is a recently described, extremely rare subtype of low-grade osteosarcoma. Two such cases were encountered among 102 cases of osteosarcoma seen in the Prince of Wales Hospital, Hong Kong, between 1984 and 1994. The first patient, a 39-year-old woman, presented with a mass in her right maxilla which was resected and mistaken as a myxoma. The tumour recurred locally four years later and she now has extensive local recurrent disease six years after initial presentation and is amenable to support treatment only. The second patient, a 28-year-old man, had a pelvic tumour which recurred in the form of a polypoid left atrial tumour and pulmonary nodules six years after operation. The left atrial tumour recurred one year after operation, and led to sudden death of the patient seven years after initial presentation. Radiologically, the tumours in both cases appeared as expansile osteolytic lesions with erosion of adjacent bone and infiltration into soft tissue. Histologically, they consisted of lobules of spindle, stellate or polygonal tumour cells showing mitotic activity and with moderate nuclear pleomorphism and hyperchromatism, set in a highly myxoid stroma superficially mimicking chondromyxoid fibroma. The histological hallmark was the direct production of osteoid by tumour cells. Chondromyxoid fibroma-like osteosarcoma merits recognition as a distinct variant of low-grade osteosarcoma for which early appropriate surgery is indicated.

Treatment of deformed tibial intramedullary nail: report of two cases

Fixation of long-bone fractures using high-tensile-strength intramedullary nails is now a well-established form of treatment. A high-energy injury may deform and angulate such nails. Such incidents are rare-only two cases have previously been reported in the literature. We report the cases of two patients with deformed intramedullary tibial nails as the result of second injury to the same leg. The bent nails were removed in the conventional manner despite the straight intramedullary canal.

Fracture of the shaft of the humerus with a fracture-dislocation of the same shoulder. A case report

We report the case of a man aged 19 who sustained an anterior dislocation of the shoulder with a fracture of the greater tuberosity, and a fracture of the shaft of the same humerus. Open reduction and internal fixation of the shaft fracture was carried out followed by closed manipulation of the dislocation. He recovered full function of the shoulder and elbow.

Necrotizing fasciitis of the foot caused by an unusual organism, Vibrio vulnificus

In modern medicine, there are very few infectious disease processes occurring in the foot that can cause death within 48 hr. and have an overall mortality rate of 50% despite appropriate antibiotic and surgical treatment. Such a condition must be regarded as being potentially deadly. The authors report a case of necrotizing fasciitis of the left foot resulting from an unusual organism of Vibrio vulnificus.

Rapid airway access by modified retrograde intubation

Rapid access to the airway is important to ensure successful resuscitation. However, the establishment of a patent airway by orotracheal intubation is not always easy. This is especially true in patients with upper airway pathology or anatomic variations. A modified retrograde intubation technique was developed using the plastic sheath of the spring guidewire of a central venous pressure (CVP) kit as an introducer. This is considered to be a simple and safe method to provide a secure airway where intubation is difficult or in an emergency. This report presents our clinical experience using this method in 10 patients.

Extraskeletal mesenchymal chondrosarcoma of the labium majus

Extraskeletal mesenchymal chondrosarcoma is a rare tumor. It has been noted to occur most commonly in muscle and the central nervous system. It has never been reported to occur in the soft tissues of the anogenital region. We report the first such case, occurring in a 40-year-old woman who presented with a 1-year history of a mass originating in the left labium majus. After extensive local resection and lymph node dissection she remains disease free after 40 months follow-up.

Long survival with metastatic clear cell sarcoma of the Achilles tendon

Clear cell sarcoma of tendons and aponeuroses is a rare tumor with a predilection for the lower extremities, particularly the foot. Although it is claimed to have a poor prognostic outlook, it is sometimes characterized by a slow clinical course. The authors report a case with a prolonged survival period of 7 years--5 years in the presence of multiple lung metastases.

Giant cell tumor of bone

Giant cell tumor is a locally aggressive tumor with a high recurrence rate if not completely excised. The condition is more common among Asians than whites. During a 10-year period 44 patients, ranging in age from 12 to 51 years, were treated. The most common sites were the proximal femur and the distal radius. The aim of treatment was to excise the tumor completely. Because the tumor usually occurred at the juxtaarticular region of the bone, difficult reconstruction was expected. The authors' method of choice for filling large defects resulting from resection was to use a large vascularized bone graft from the iliac crest to enhance bone to bone corporation. The recurrence rate was low (4.5%), with only 2 recurrences: 1 at the proximal femur and the other at the proximal tibia. The functional results were highly satisfactory, with excellent stability of the joint, although in the case of the distal radius there was some degree of subluxation of the wrist joint. By applying microsurgical technique for the reconstruction, one was able to be more aggressive with excision of this locally aggressive tumor while maintaining excellent functional results. In the case of the knee, as long as 1 tibial condyle was intact, reconstruction of the other condyle using a vascularized iliac crest block maintained the joint integrity perfectly or created a pseudojoint component that was perfectly stable.

The osteoporotic spine

With an aging population, osteoporotic vertebral collapse is an increasingly common condition in both the Western and Eastern hemispheres. This review looked into the situation in Hong Kong with the aim of highlighting the major differences in data from the Western. Between 1989 and 1994, 497 patients with osteoporotic vertebral collapse, aged 65 to 94 years old, were admitted under the authors' care, with a female to male ratio of 5:1. More than 1/3 of the patients had fracture involving 1 single vertebra. The mean hospital stay was 5 days, with an additional 6 to 23 days in a convalescent hospital. Complication of spinal cord compression is uncommon and occurred in only 10 patients (2%) in this series who were treated mostly with anterior decompression and iliac crest graft with varying degrees of neurologic recovery. Despite the general benign nature of the problem, the high morbidity and the long hospital stays undoubtedly are significant drains on health care resources.

Surgical management of patients with osteogenesis imperfecta: 10 years' experience

The orthopedic problems of osteogenesis imperfecta (OI) are multiple and formidable, if not untreatable. Controversy surrounds the timing and method of its management and to date, no reports have been published on the orthopedic treatment of these patients in Taiwan. This paper reports the surgical treatment of eight OI patients (average age, 3 yr 5 mo) who were unable to walk before surgery. Preoperatively, the incidence of long bone fracture ranged from once per month to twice per year. The average degree of femoral and tibial bowing as measured from leg radiographs at the first visit were 42 degrees and 32 degrees, respectively. Four patients underwent intramedullary nailing of both the femur and tibia while another four patients underwent intramedullary nailing of the femur only in the primary operation. The implants used were mostly Steinmann pins or Rush nails, and a femoral Kuntscher nail was used in one case. At the mean postoperative follow-up period of 5 years 4 months, five patients could walk independently without support. Two walked with wheel-carts and one could rise and stand with minimal support. We conclude that patients with OI can benefit from early surgical correction and stabilization and experience improvement in their ambulatory status despite the multiple procedures required.

Osteosarcoma in Hong Kong

Since 1984, the authors have treated 82 Chinese patients with sarcoma of bone. Of these patients, 58 had high grade osteosarcomas in the extremities. Of the 41 patients available for examination, the age range was 8 to 59 years, with a median of 17 years. Treatment consisted of preoperative and postoperative neoadjuvant chemotherapy, limb salvage surgery, or amputation. The overall survival rate was 62.9% at 2 years and 43% at 5 years. No significant difference was found in survival between the amputation and limb salvage groups, although local control was much better in the amputation group. There seemed to be better survival for patients who had a good response to preoperative chemotherapy, although the data did not reach statistical significance.

Antenatal sonographic diagnosis of clubfoot: a six-year experience

In the period 1988 through 1993, 6351 pregnant women were referred to the Department of Obstetrics and Gynaecology, University "La Sapienza", Roma, for suspected fetal anomalies or maternofetal problems. All underwent serial transabdominal and/or transvaginal ultrasound scanning, which revealed a total of 235 fetuses with hydrocephalus, cardiac, or musculoskeletal malformations. Forty-one clubfeet were detected in 27 pregnancies in the early part of the second trimester of pregnancy. Of these, 14 feet in eight patients were isolated, and were classified as idiopathic. A clubfoot was associated with neural tube defects in six patients, with anomalies of the urinary and/or digestive system in a further six, with a cystic hygroma in two, and with other musculoskeletal abnormalities in the other six patients. Amniocentesis revealed an abnormal karyotype in six fetuses (22.2%). In only two cases was oligohydramnios present. In both these patients, a fetal urinary tract malformation was present Polyhydramnios was found in 18 cases, and a normal amount of amniotic fluid was found in the remaining seven cases. Polyhydramnios was present in six of the eight idiopathic clubfoot fetuses. Clubfoot is associated with musculoskeletal and visceral anomalies in a high proportion of cases. The association of clubfoot with polyhydramnios in a high proportion of cases does not support the hypothesis of intrauterine moulding as an etiological factor in its development. Ultrasonographical prenatal detection of a clubfoot should prompt amniocentesis, as the condition is associated with an abnormal karyotype in a significant proportion of cases.

A pelvic osteosarcoma with metastasis to the donor site of the bone graft. A case report

A patient with a pelvic osteosarcoma was treated by resection and a vascularised fibular bone graft. A metastasis developed at the donor site of the graft.

Limb salvage surgery with microsurgical reconstruction for the treatment of musculoskeletal tumours involving the upper extremity

Microsurgical reconstructive techniques have been applied in the management of 14 patients with malignant bone and soft tissue tumours as well as for 30 patients with benign but aggressive bone lesions affecting the upper extremity. Vascularised bone grafts were used in 6 patients with malignant bone tumours and 30 patients with aggressive bone lesions. Reconstruction with soft tissue free flap transfer was required in 6 patients with soft tissue defects, primarily following excision of soft tissue tumours in 2 and after excision of recurrent tumours in 4 patients. Microneural dissection and vascular reconstruction were performed in 2 patients with tumours around the major neurovascular bundles. The patients were followed up for varying periods, ranging from 1 to 12 years and assessment of the limb function was performed using Enneking's system of evaluation. There were no local recurrences. In the malignant tumour group, 3 patients died of systemic disease, 7 were alive but with disease and 4 were disease free. Extremity function was excellent in 3 patients, good in 6 patients, fair in 4 patients and poor in 1 patient. In the benign bone tumour group, extremity function was graded as excellent in 12 patients, good in 14 patients, fair in 3 patients and poor in 1 patient. The vascular bone grafts united in all but 3 patients at 4 months following surgery. Minimal donor site complications had been recorded and there had been no failures. Useful limb salvage may thus be achieved with the application of microsurgical techniques for a variety of indications in limb salvage surgery after tumour excision.

Extraosseous osteogenic sarcoma of the mediastinum occurring in a Chinese patient

Osteogenic sarcoma can occur rarely in soft tissues, predominantly of the proximal lower limbs. The mediastinum is a less common site, with only five reports in the literature. We report a case occurring in a young Chinese man and review the literature.

Vibration arthrometry of the knee with torn meniscus: a preliminary report

Although projects using vibration signals generated by the joint to detect joint disorders are still experimental, vibration arthrometry has been shown to be useful in assessing meniscal pathology. A prospective study using vibration arthrometry to diagnose meniscal tears was carried out in 25 consecutive patients with knee injuries. They comprised 20 males and five females with an average age of 34 years. An arthroscopic examination of the injured knee was given to every patient. Six cases of medial meniscal tear, 12 lateral meniscal tear, and two torn discoid menisci were found. The remaining five cases had normal menisci. By correlating the vibration arthrography of the patients to their corresponding arthroscopic findings, 15 were found to be true-positive, five true-negative and five false-negative. There were no false-positive readings. The accuracy, sensitivity and specificity of the vibration arthrometry in diagnosing meniscal tear was 80%, 75% and 100%, respectively. Vibration arthrometry was shown to be a reliable, non-invasive diagnostic tool in diagnosing meniscal tear of the knee.

Posterior slope angle of the medial tibial plateau

The overall average of the posterior slope of the medial plateau of the tibia as determined from the lateral radiography of the knee was 10 degrees +/- 4 degrees, with a range from 0 degrees to 20 degrees. This value was independent of age and gender and was unaffected by arthrosis as long as the arcuate contours of the medial socket were not eroded and could be identified by lateral radiography. While the average value of this posterior slope was similar to that of a cadaveric study, the range was much greater. The current practice of neglecting the preoperative posterior tibial slope and arbitrarily setting the tibial component at a predetermined posterior tilt angle failed to take into account the wide variation in posterior tibial slope.

Patellar thickness in total knee replacement

The question of patellar thickness after total knee replacement (TKR) is an important issue. From November 1989 to June 1993, a total of 294 TKR were performed on 219 patients (34 males, 185 females) with an average age of 67 years. Tricon-M prostheses were used in TKRs performed before October 1992, and PCA prostheses were used after that date. In each TKR, all polyethylene patellar components used on patellar resurfacing were cemented in place. The average preoperative patellar thickness was 21.2 +/- 1.8 mm. The thickness was preserved in 106 knees, while for 53 knees, a slight increase in thickness (mean, 1.5 +/- 0.9 mm) was recorded, and for 120 knees, a slight decrease in thickness (mean, 1.5 +/- 0.8 mm) was recorded. Lateral retinacular release was performed in 96 knees (40%) of the 238 TKR with a Tricon-M prosthesis, but in only seven knees (17%) among the 41 TKR using the PCA prosthesis. Patellar subluxation and dislocation after TKR occurred in 13 knees of 11 patients (10 females, one male, mean body weight 63.5 kg) with the Tricon-M prosthesis. The mean time from arthroplasty to occurrence of patellar instability was eight months. Six knees were treated by proximal realignment procedure while seven knees were given conservative treatment, with good results and no recurrence reported. The use of a patellar cutting jig allows better control of patellar thickness when performing patellar resurfacing for small patella. No complications such as patellar fracture, infection or patellar component-loosening were encountered in the 294 TKRs performed.

Palmar hyperhidrosis in children: treatment with video endoscopic laser sympathectomy

Palmar hyperhidrosis (PH) often starts in childhood and can be a disabling condition for a significant number of young children at the age they begin primary school. There are few reports regarding the surgical treatment of PH in children. The authors report on 40 PH patients under 16 years of age treated with video thoracoscopic laser sympathectomy; there has been substantial experience with this procedure for the treatment of adults with PH. A satisfactory result, with very low morbidity, was achieved for all 40 children. The surgical technique is described briefly. With the technique, the proper sympathetic segment is visualized in almost all cases and then definitely ablated with a fiberoptic low-power laser while under the aid of sympathetic monitoring. Consequently, an adequate sympathectomy warranting a long-lasting therapeutic effect can be achieved without the need of tissue diagnosis. No case required conversion to open sympathectomy. Neither injury to the lung nor bleeding was encountered. Horner's syndrome did not occur in any case. Bilateral sympathectomy was accomplished generally within 30 minutes. All patients were discharged after an overnight stay and are doing well with normal activities. The most frequent complication was compensatory hyperhidrosis, which was tolerable after reassurance. Based on the accumulated experience, it is justified to recommend early surgery, with this refined technique, in cases of severe PH in children.

Reconstruction of extensor mechanism after trauma and infection by transposition of the Achilles tendon: report of technique and four cases

High-energy injuries to the knee often involve extensive soft tissue loss as well as fractures. In certain situations, the patellar tendon may be lost due to initial injury or post-injury complications such as infection. Use of the gastrocnemius flap is a popular method of covering the defect as well as controlling infection and promoting healing by increasing local vascularity. We present a method of reconstructing the patellar tendon by extending the use of the gastrocnemius flaps using its Achilles tendon and calcaneal insertion. The distal insertion of the Achilles tendon is fixed to the tibial tuberosity with a cancellous screw, and the proximal end is sutured to the quadriceps muscles. The knee is immobilized for 1 week, after which the knee is mobilized in a hinged brace. Three of the four cases had good results, one a moderate result (the initial injury was extensive, with dislocation of the knee).