The Documentation of Injuries Caused by Traffic Accidents

BACKGROUND

Persons injured in traffic accidents may have injuries of characteristic types that are of significance for the complex reconstruction of the accident and whose medicolegally sound clinical documentation is highly important. This is of particular relevance for the approximately 55 000 persons who are severely injured in traffic accidents in Germany each year. Gaps in documentation are often disadvantageous for the injured persons.

METHODS

This review is based on pertinent publications retrieved by a selective literature review, with additional consideration of relevant textbooks in traffic medicine and legal medicine, as well as the guidelines of the AWMF (Association of the Scientific Medical Societies in Germany).

RESULTS

Injuries in traffic accidents typically differ depending on the mode of participation of the injured person in traffic. They must be examined with a view toward the sequence of events of the accident and documented in medicolegally sound fashion. In particular, because of the different mechanical forces involved, it is important to document the seat that the injured person occupied in the automobile, the nature of the collision (pedestrian vs. automobile; bicycle, e-bike, e-scooter, and motorcycle accidents), and the protective devices that were in use.

CONCLUSION

The precise documentation of injuries and examination findings, with critical consideration of their plausibility in relation to the sequence of events of the accident as far as it is known, is an important duty of the physician. This documentation serves as the basis for further judicial steps leading to compensation when legally appropriate.

Cortical Desmoid of the Distal Femur-Incidentaloma or Insertional Tendinopathy?

BACKGROUND

The cortical desmoid (DFCI) of the posteromedial femoral condyle is considered an asymptomatic incidental finding in adolescents without clinical relevance. The aim of this study was to evaluate the clinical relevance of DFCI from both a tumor orthopedic and sports medicine point of view.

METHODS

n = 23 patients (13.74 ± 2.74 years; nineteen female, four male) with DFCI of the posteromedial femoral condyle were included. A localized posteromedial knee pain on exertion was differentiated from non-specific knee pain. Symptom duration, additional pathologies, number of MRIs, sports activity and training intensity, downtime, therapeutic modalities, and relief/remission of symptoms were documented. The Tegner activity scale (TAS) and Lysholm score (LS) were collected. The influence of specific posteromedial pain, MRI presence of paratendinous cysts, sports level as well as physiotherapy on downtime and LS/TAS was statistically analyzed.

RESULTS

100% reported knee symptoms at initial presentation. A localized posteromedial pain was documented in 52%. In 16/23 (70%) additional functional pathologies were diagnosed. Patients were physically highly active with high training intensities (6.52 ± 5.87 h/week) and performance level (65% competitive vs. 35% recreational). Patients underwent 1.91 ± 0.97 MRIs (max four). Symptom duration was 10.48 ± 11.02 weeks. A follow-up examination was performed after 12.62 ± 10.41 months (n = two lost to follow-up). 17/21 had physiotherapy, on average 17.06 ± 13.33 units. Overall downtime was 13.39 ± 12.50 weeks, the return-to-sports (RTS) rate 81%. 100%/38% reported a relief/remission of complaints. LS was 93.29 ± 7.95, median TAS before onset of knee complaints/at follow-up 7 (6-7)/7 (5-7). Specific posteromedial pain, presence of paratendinous cysts, sports level and physiotherapy had no significant influence on downtime and outcome parameters (n.s.).

CONCLUSIONS

DFCI as a pathognomonic finding is recurrently encountered in the MRIs of children and adolescents. This knowledge is essential to spare patients from overtreatment. Contrary to the literature, the present results implicate a clinical relevance of DFCI particularly in those who are physically highly active with localized pain on exertion. Structured physiotherapy as basic treatment is recommended.

[E-scooter, e-bike and bicycle injuries in the same period-A prospective analysis of a level 1 trauma center]

BACKGROUND

The actual number of accidents in e‑scooter drivers in Germany seems to be significantly higher than the current figures from the Statistisches Bundesamt suggest. This epidemiological study examines e‑scooter injuries and compares them with e‑bike and bicycle injuries.

OBJECTIVE

In order to create a comparable database on the dangers of e‑scooters, e‑bikes and bicycles, the typical injury patterns were analyzed and prevention options derived from them.

MATERIAL AND METHODS

All accidents involving e‑scooters, e‑bikes and bicycles that were presented via the university emergency room of a level 1 trauma center between 15 June 2019 and 31 October 2020 were prospectively investigated.

RESULTS

In our study, 68 accidents in e‑scooter drivers were included, of which only 11.8% (n = 8) were recorded by the police. Significantly more of them were male than female (p = 0.032) with a mean age of 31.1 (±13) years. At the same time, we registered 34 accidents in e‑bike riders and 356 in cyclists. In all three groups, most injuries occurred to the head, followed by injuries to the upper extremities. Significantly more e‑scooter drivers had an ISS ≥ 16 than in the group of injured cyclists (p = 0.016). E‑scooter riders who had an accident had a significantly longer length of stay in hospital, than e‑bike riders (p = 0.003) and cyclists (p = 0.001), 52.9% (n = 18) of e‑bike riders and 53.3% (n = 113) cyclists wore a helmet, compared to only 1.5% (n = 1) of e‑scooter riders. The most common cause of accidents among e‑bike riders (17.7%; n = 6) and cyclists (10.4%; n = 37) was slipping away on tram rails, while for e‑scooter riders it was colliding with a curb (7.4%; n = 5).

CONCLUSION

The three patient collectives examined showed different causes and profiles of injuries. The reasons for an increased proportion of seriously injured people compared to cyclists are electromobility, driving under the influence of alcohol and inadequate wearing of a helmet on e‑scooters when head injuries dominate. 73.5% (n = 50) of the e‑scooter accidents recorded by us were not registered by the police and therefore do not appear in the current statistics of the statistisches Bundesamt. As a result, a much higher number of e‑scooter accidents can be assumed. Preventive measures could include the introduction of compulsory helmets, a higher number of traffic controls and the expansion of bike tracks.

Increased UHMWPE Particle-Induced Osteolysis in Fetuin-A-Deficient Mice

Particle-induced osteolysis is a major cause of aseptic prosthetic loosening. Implant wear particles stimulate tissue macrophages inducing an aseptic inflammatory reaction, which ultimately results in bone loss. Fetuin-A is a key regulator of calcified matrix metabolism and an acute phase protein. We studied the influence of fetuin-A on particle-induced osteolysis in an established mouse model using fetuin-A-deficient mice. Ten fetuin-A-deficient (Ahsg−/−) mice and ten wild-type animals (Ahsg+/+) were assigned to test group receiving ultra-high molecular weight polyethylene (UHMWPE) particle implantation or to control group (sham surgery). After 14 days, bone metabolism parameters RANKL, osteoprotegerin (OPG), osteocalcin (OC), alkaline phosphatase (ALP), calcium, phosphate, and desoxypyridinoline (DPD) were examined. Bone volume was determined by microcomputed tomography (μCT); osteolytic regions and osteoclasts were histomorphometrically analyzed. After particle treatment, bone resorption was significantly increased in Ahsg−/− mice compared with corresponding Ahsg+/+ wild-type mice (p = 0.007). Eroded surface areas in Ahsg−/− mice were significantly increased (p = 0.002) compared with Ahsg+/+ mice, as well as the number of osteoclasts compared with control (p = 0.039). Fetuin-A deficiency revealed increased OPG (p = 0.002), and decreased levels of DPD (p = 0.038), OC (p = 0.036), ALP (p < 0.001), and Ca (p = 0.001) compared with wild-type animals. Under osteolytic conditions in Ahsg−/− mice, OPG was increased (p = 0.013), ALP (p = 0.015) and DPD (p = 0.012) were decreased compared with the Ahsg+/+ group. Osteolytic conditions lead to greater bone loss in fetuin-A-deficient mice compared with wild-type mice. Reduced fetuin-A serum levels may be a risk factor for particle-induced osteolysis while the protective effect of fetuin-A might be a future pathway for prophylaxis and treatment.

[Rupture of the pectoralis major muscle in amateur athletes: a rare injury or often overlooked?]

INTRODUCTION

A rupture of the pectoralis major muscle is a rare injury pattern overall, but it is frequently described in athletes, particularly in weightlifting. The risk of sustaining this type of injury is present especially during the eccentric phase of muscle loading. An association between such injuries and the abuse of anabolic steroids is described in the literature, but there is no coherent evidence to support this. We report the case of a young patient with a normal habitus who suffered a humeral rupture of the pectoralis major muscle during recreational sports. There was no history of excessive weight training or use of anabolic steroids.

CASE HISTORY

This 33-year-old patient reported a sudden onset of left pectoral pain during training on the chest fly machine as well as a whip-like popping sound, followed by an immediate painful restriction of movement in the left arm. A clinical examination revealed a mild haematoma located on the left medial upper arm with localised tenderness and a discrete asymmetry of the contour of the pectoral muscles. Due to the typical medical history, we established the indication for surgical exploration although the clinical picture was rather discrete and only an incomplete rupture was seen in an MRI scan. Intraoperatively, we detected a complete rupture of the sternocostal part of the pectoralis major muscle with marked retraction and haematoma. Reinforcement and reinsertion were performed at the "footprint" using titanium anchors (2 x 5.5mm Corkscrew FT, Arthrex, Florida). The patient was able to resume his sports activities at the pre-traumatic level four months after surgery.

CONCLUSION

A rupture of the insertion of the pectoralis major muscle must also be considered in amateur athletes with a typical history. The characteristic clinical symptoms described in the literature mostly refer to competitive athletes and bodybuilders, but these injuries can also be diagnosed in amateur athletes with lower muscle mass by subtle clinical examination. Nevertheless, there is a considerable risk of underestimating the extent of the injury. In case of doubt, surgical exploration should be performed promptly in amateur athletes. Surgical refixation of the humeral rupture of the pectoralis major muscle is the gold standard and should not be reserved to high-performance athletes.

Injuries and Overuse Injuries in Show Jumping—A Retrospective Epidemiological Cross-Sectional Study of Show Jumpers in Germany

This retrospective cross-sectional epidemiological study deals with sport-specific injury patterns in show jumping. A total of 363 show jumpers of all levels (S) answered a retrospective questionnaire about injuries and overuse damages which occurred in the course of their careers. Demographic data and information on injuries in various body regions were collected. In addition to descriptive analysis, significance tests were performed. For better statistical comparability with other sports, exposure time was extrapolated with total career duration and weekly training hours, and injuries per 1000 jumping hours were calculated. The study included 251 (69%) women and 112 (31%) men, who were on average 26.9 ± 10.9 years old. The injury rate for the entire collective was 3.7 per 1000 h of exposure. The most frequently affected body region was the head (31%). Overuse complaints play a subordinate role and mainly affect the upper extremities (65%). The riders of the professional lower performance levels are less likely to injure themselves per 1000 h than riders of the higher performance levels. Riders who often or always wore a helmet suffered significantly fewer head injuries (p = 0.008) and had a significantly lower total injury duration than riders who did not wear a helmet (p = 0.006). Similarly, the study showed that riders who often or always wore a safety vest suffered significantly fewer spinal injuries (p = 0.017) and had significantly fewer injuries per 1000 riding hours (p = 0.031) than riders who did not wear a safety vest. Based on the present results, there should be an extension of the general helmet requirement and a requirement to wear safety vests in show jumping in general.

Geriatric Proximal Femur Fractures During the Covid-19 Pandemic - Fewer Cases, But More Comorbidities

Background:

The COVID-19 pandemic is challenging healthcare systems worldwide. This study examines geriatric patients with proximal femur fractures during the COVID-19 pandemic, shifts in secondary disease profile, the impact of the pandemic on hospitalization and further treatment.

Methods:

In a retrospective monocentric study, geriatric proximal femur fractures treated in the first six months of 2020 were analyzed and compared with the same period of 2019. Pre-traumatic status (living in a care home, under supervision of a legal guardian), type of trauma, accident mechanism, geriatric risk factors, associated comorbidities, time between hospitalization and surgery, inpatient time and post-operative further treatment of 2 groups of patients, aged 65-80 years (Group 1) and 80+ years (Group 2) were investigated.

Results:

The total number of patients decreased (70 in 2019 vs. 58 in 2020), mostly in Group 1 (25 vs. 16) while the numbers in Group 2 remained almost constant (45 vs. 42). The percentage of patients with pre-existing neurological conditions rose in 2020. This corresponded to an increase in patients under legal supervision (29.3%) and receiving pre-traumatic care in a nursing home (14.7%). Fractures were mostly caused by minor trauma in a home environment. In 2020, total number of inpatient days for Group 2 was lower compared to Group 1 (p = 0.008). Further care differed between the years: fewer Group 1 patients were discharged to geriatric therapy (69.6% vs. 25.0%), whereas in Group 2 the number of patients discharged to a nursing home increased.

Conclusions:

Falling by elderly patients is correlated to geriatric comorbidities, consequently there was no change in the case numbers in this age group. Strategic measures to avoid COVID-19 infection in hospital setting could include reducing the length of hospital stays by transferring elderly patients to a nursing home as soon as possible and discharging independent, mobile patients to return home.

Injuries in underwater rugby: a retrospective cross-sectional epidemiological study

INTRODUCTION

Underwater rugby (UWR) is a team sport which combines swimming sprints, apnoea diving, a good overview of the three-dimensional underwater space and wrestling for the ball.This was the first epidemiological study of UWR injuries in a large international collective.

METHODS

A questionnaire containing 124 questions was distributed to 198 active UWR players and completed under the supervision of medical staff. Demographic data and information about injuries in ten different body regions were collected.

RESULTS

Of the 198 respondents, 106 (53.5%) were male and 92 (46.5%) were female. On average, each UWR player suffered a median of 19.5 (IQR 44) injuries. Based on the exposure time, means of 37.7 (SD 90.0) injuries per 1000 playing hours per player and 9.9 (20.1) injuries per year were found. Significant injuries mainly occurred to the head region (45.7%). Bruises and sprains were observed more often than fractures and dislocations. Male athletes had a longer total injury break time (median 4.8 [IQR 10.5] days), than female athletes (4 [8.6] days). Female athletes had more injuries (median 20 [IQR 26.8]) than male athletes (18.5 [63]). The length of the injury-related break time increased with the rise in body mass index.

CONCLUSIONS

The risk of severe injury in UWR is low compared to other ball sports like water polo and rugby. UWR is played under water and the impact of tackles is lessened by the water. Further studies should record chronic injuries in UWR and establish measures to prevent injury.

Development of Case Numbers during the COVID-19 Pandemic in a Center of Maximum-Care for Traumatology and Orthopedic Oncology

(1) Background: The COVID-19 pandemic has led to a significant change in the utilization of trauma surgery and tumor orthopedic hospital facilities. (2) Methods: In a monocentric retrospective analysis, the weekly numbers of cases requiring intra-clinical treatment in the first four months of 2020 were compared with those of 2019. Patients' visits to the emergency department and shock room, consultation hours, work-related accidents, case numbers in the normal and intensive care units, ventilation hours, the "Simplified Acute Physiology Score/ Therapeutic Intervention Scoring System" (SAPS/TISS), the average length of stay in hospital, the number of operations and their degree of urgency, as well as deaths, were analyzed in a study based on the data from 7606 outpatient consultations in 2019 and 6755 in 2020, as well as 993 inpatient cases in 2019 and 950 in 2020. (3) Results: There was a significant reduction in the number of treatments per week in the emergency department (261 ± 29 vs. 165 ± 25; p < 0.001) with the same number of shock room treatments and fewer consultation hour contacts (226 ± 29 vs. 119 ± 65; p = 0.012). There were fewer inpatient cases (66 ± 7 vs. 42 ± 11; p = 0.001), resulting in a fall in the days of hospitalization (492 ± 63 vs. 308 ± 78; p < 0.001) and number of operations (73 ± 7 vs. 55 ± 10; p = 0.012), especially elective procedures (20 ± 3 vs. 7 ± 7; p = 0.008). The SAPS/TISS score was lower (1351 ± 1213 vs. 399 ± 281; p = 0.023). Fewer fracture treatments and septic surgeries were performed, while the number of procedures to treat orthopedic malignancies remained constant. (4) Conclusions: During the first phase of the COVID-19 pandemic, we observed a significant reduction in the number of cases treated in orthopedics. While the number of multiple-injured patients was unchanged, fewer patients presented for primary and regular care. Treatment of acute injuries and malignant tumor diseases was not at risk. There was no effect on in-house mortality. We see a potential for the recruitment of medical staff from the outpatient department, operating room, and the ward. In the event of a future second wave, our results may allow for early planning, particularly of the all-important human resources. Reorganization by hospitals and decreased patient numbers in trauma surgery can enable the reallocation of medical staff, equipment, and beds to increase capacity for COVID-19 patients.

[Injuries in inline skater hockey]

In Germany, Inline Skater Hockey (ISH) is played by about 7500 active players on inline skates with equipment comparable to ice hockey using a hard-plastic ball. The aim of this retrospective epidemiological cross-sectional study is to record the frequency and types of injuries in this sport, for which there is a lack of medically adequate studies in the literature. A questionnaire comprising 112 items was used to collect demographic data, injuries in eight body regions and defined overuse injuries. 274 ISH players with an average age of 24.5 ± 6.2 years and an exposure time of 2787 ± 2063 hours were examined. 5701 injuries were recorded, 60.5 % of which were minor bruises, abrasions and wounds. The total injury rate per 1000 hours was 9.6 ± 17.7, with an injury-related break of 12.8 ± 21.8 weeks per player. Field players with visors had highly significantly fewer head injuries (2.8 ± 6.1 vs. 8.9 ± 13.1; p < 0.001) with highly significantly (p < 0.001) fewer lacerations, nasal bone fractures, eye injuries and dental injuries. There was a weak negative correlation between facial protection and number of head injuries (r = -0.386, p < 0.001). In conclusion, frequency and types of injuries in ISH are comparable to ice hockey during training. In accordance with ice hockey, protective equipment in ISH can significantly reduce the occurrence of head injuries. Preventive attention should be paid to the wearing of a full visor and to education about the occurrence of concussions despite the use of a protective helmet.

Lollipop Sign - Ossification at Wire Ends after Osteosynthesis?

Introduction:

Heterotopic ossification (HO) is abnormal formation of new bone in the soft tissue. HO occurs outside the normal bone within soft tissues such as muscles and tendons, and histologically, it is no different from skeletal bone. It is still not clear what factors stimulate HO. The soft tissue around the hip joint has been identified as the most common location for HO. Patients with HO usually have no clinical symptoms; however, it can become very painful and lead to severe functional limitations. The standard diagnostic procedure consists of conventional X-ray diagnostics and/or skeletal scintigraphy. Local radiation and nonsteroidal anti-inflammatory drugs are the classical options for treatment and prophylaxis of HO. We describe two pediatric patients with “lollipop-like” HO at the end of Kirschner wires (K-wires, steel) and titanium elastic nails (TENs, titanium).

Case Report:

A 9-year-old girl, 1 year after Salter and Pemberton osteotomy with K-wires, and a 15-year-old boy, 1 year after fracture of the right femur treated by osteosynthesis with TENs, were treated in our department due to HO. The girl did not report any symptoms, while the boy had pain in the location where the ossification had formed. However, examination of the girl’s hip showed that the range of motion in the hip affected by HO was limited in comparison with the opposite unaffected hip.

Conclusion:

To the best of our knowledge, lollipop-like HO around protruding K-wires or TENs has not yet been described. According to literature, HO is mainly located in the pelvic region and at the elbow. Most studies investigating HO describe cases which have occurred after cemented or uncemented hip replacement surgery. In the cases presented here, HO might have been stimulated by repetitive muscle trauma above the protruding K-wire and TENs, the trauma caused by the operation, bone marrow cells dispersed intraoperatively, or by a combination of these and other factors. There are numerous studies on strategies to prevent HO after joint replacement. We suggest “lollipop sign” as a name for this rare type of HO around the end of K-wires/TENs in pediatric patients.

Improved repair of chondral and osteochondral defects in the ovine trochlea compared with the medial condyle

Associations between topographic location and articular cartilage repair in preclinical animal models are unknown. Based on clinical investigations, we hypothesized that lesions in the ovine femoral condyle repair better than in the trochlea. Full-thickness chondral and osteochondral defects were simultaneously established in the weightbearing area of the medial femoral condyle and the lateral trochlear facet in sheep, with chondral defects subjected to subchondral drilling. After 6 months in vivo, cartilage repair and osteoarthritis development was evaluated by macroscopic, histological, immunohistochemical, and biochemical analyses. Macroscopic and histological articular cartilage repair and type-II collagen immunoreactivity were better in the femoral trochlea, regardless of the defect type. Location-independently, osteochondral defects induced more osteoarthritic degeneration of the adjacent cartilage than drilled chondral lesions. DNA and proteoglycan contents of chondral defects were higher in the condyle, reflecting physiological topographical differences. The results indicate that topographic location dictates the structural patterns and biochemical composition of the repair tissue in sheep. These findings suggest that repair of cartilage defects at different anatomical sites of the ovine stifle joint needs to be assessed independently and that the sheep trochlea exhibits cartilage repair patterns reflective of the human medial femoral condyle.

Measles virus replication in lungs of hispid cotton rats after intranasal inoculation

Hispid cotton rats were inoculated intranasally with either measles virus (MV) Edmonston, a multipassaged, tissue culture-adapted strain of MV, or with one of three clinical MV isolates that had limited passages (three to five times) in tissue culture cells. MV Edmonston was recovered from the lungs of every (n = 37) hispid cotton rat inoculated with this virus for at least 7 days after virus inoculation. Peak pulmonary titers occurred on Day +4 (3.3-4.4 log10/g lung). Scattered areas of inflammation were observed interstitially in lung sections from infected animals stained with hematoxylin and eosin, and a similar pattern of diffuse fluorescence was seen in cryostat sections stained with an indirect fluorescent antibody procedure specific for virus antigens. Fluorescent antibody and virus isolation studies on lung lavage cells both suggested that lung leukocytes were a primary target of the virus. In contrast to these findings, virus was isolated only sporadically from hispid cotton rats inoculated with any of the clinical measles virus isolates. Despite the restricted growth of MV in these animals, cotton rats may be useful for studying certain aspects of measles virus pathogenesis and for screening potential antiviral compounds in vivo.

Evaluation of the immunogenicity and protective efficacy of a candidate parainfluenza virus type 3 subunit vaccine in cotton rats

A parainfluenza virus type 3 (PIV3) subunit vaccine consisting of detergent-solubilized, affinity-purified haemagglutinin-neuraminidase (HN) and fusion (F) surface glycoproteins was tested in cotton rats for immunogenicity, short-term effects on virus-induced immunopathology and protective efficacy. Groups of animals were immunized twice, 4 weeks apart, with graded doses of vaccine administered either alone or with aluminium phosphate (AlPO4). The minimum immunogenic dose of vaccine was 0.1 microgram HN and F when the vaccine was given alone and 0.01 microgram when the vaccine was administered with AlPO4 adjuvant. Antibody responses in animals immunized with 1 microgram HN and F mixed with adjuvant were similar to those in control animals infected with live PIV3 intranasally. Pulmonary and nasal wash PIV3 titres generally were inversely correlated with serum antibody levels. Virus titres were significantly reduced in all groups of animals immunized with greater than or equal to 0.1 microgram HN and F compared with control animals immunized with vehicle only. Four days after virus challenge, there was no evidence of enhanced histopathology in lung sections from animals immunized with the candidate vaccine.

Evaluation of the toxicity and antiviral activity of carbocyclic 3-deazaadenosine against respiratory syncytial and parainfluenza type 3 viruses in tissue culture and in cotton rats

The toxicity and antiviral efficacy of carbocyclic 3-deazaadenosine (Cc3Ado) against respiratory syncytial (RSV) and parainfluenza type 3 (PIV3) virus infections were tested in tissue culture and in cotton rats. The mean median efficacious dose (ED50) of Cc3Ado in HEp2 cells against RSV and PIV3 was 9 and 14 micrograms/ml, respectively. These values were 85- and 55-fold less than the median inhibitory (toxic) dose (ID50) of Cc3Ado in this cell line (750 micrograms/ml), and similar to values obtained for ribavirin. Cc3Ado exhibited no significant antiviral activity against influenza A, influenza B, adeno type 5 or adeno type 7 viruses (all ED50 were greater than 1000 micrograms/ml). In cotton rats, animals given greater than or equal to 1 mg/kg/day Cc3Ado intraperitoneally on days 1, 2 and 3 after experimental challenge with virus, consistently had significant reductions in pulmonary RSV and PIV3 titers compared to pulmonary virus titers in comparably treated control animals. The minimum efficacious dose of ribavirin given under the same conditions was 30 mg/kg/day. Cc3Ado was also efficacious in cotton rats when given orally by gavage, or when different administration schedules were used. The median efficacious dose of Cc3Ado when given orally was 10 mg/kg/day. No significant toxic effects were noted in cotton rats, even in animals given 20 mg/kg daily for eight consecutive days.

Toxicity and antiviral activity of LY253963 against respiratory syncytial and parainfluenza type 3 viruses in tissue culture and in cotton rats

LY253963, the sodium salt of 1,3,4-thiadiazol-2-ylcyanamide, was evaluated in tissue culture and in cotton rats for toxicity and antiviral efficacy against respiratory syncytial (RSV) and parainfluenza type 3 (PIV3) viruses. The selective index (ratio of the median toxic dose: median efficacious dose) of LY253963 in HEp2 tissue culture cells was greater than 100 against both RSV and PIV3. When given intraperitoneally to cotton rats, the minimum protective dose of LY253963 against both of these viruses was between 1 and 3 mg/kg/day. In contrast, doses of LY253963 as high as 30 mg/kg/day, administered orally after experimental inoculation of virus, did not significantly reduce pulmonary virus titers in treated animals compared to control animals given placebo. No toxic effects were noted in cotton rats, even in those given 20 mg/kg/day for eight consecutive days.