Accidents and injuries among U.S. Navy crewmembers during extended submarine patrols, 1997 to 1999.

Accidents and injuries, the most common cause of morbidity in military populations, result in a significant number of work days lost each year and account for 75% of all active duty deaths. Rates of accidents and injuries during U.S. Navy submarine deployments have not been evaluated previously. A database designed to monitor the health of submarine crew-members was used to examine the rates and causes of accidents among deployed crewmembers aboard 196 submarine patrols between 1997 and mid 1999. The most common category of injuries was open wounds, followed by sprains and strains, contusions, superficial injuries, burns, and others. Rates of accidents and injuries decreased with increasing age and duration of military service. Among submariners working in supply departments, the rates were more than two times those of crewmembers working in other departments. Based on these data, among a submarine crew of 100 men at sea for 100 days, approximately four to five accidents or injuries might be expected and would result in an average of about 2 days of light or no duty per injury. Rates of accidents and injuries were very low; however, focused safety training could reduce rates among younger and less experienced crewmembers as well as among those working in particular areas of the submarine.     

Use of a New High-Activity Arthroplasty Score to Assess Function of Young Patients With Total Hip or Knee Arthroplasty

The High-Activity Arthroplasty Score (HAAS) was specifically developed to assess subtle variations in functional ability after lower limb arthroplasty with particular regard to highly functioning individuals. The score was a 4-item self-assessment measure covering the 4 domains of walking, running, stair climbing, and general activities, with a possible score ranging from 0 to 18 points. The score was validated in 22 patients (total hip arthroplasty [THA], n = 11; total knee arthroplasty [TKA], n = 11) by comparison with the Oxford, Knee Society, Harris Hip, and Short WOMAC scores. The HAAS was then administered to 152 high-functioning arthroplasty patients (THA, n = 99; TKA, n = 53), all younger than 66 years. The HAAS produced a much wider range of scores, allowing greater differentiation of level of function between patients in assessing performance after TKA or THA.     

COVID-19 in pediatric kidney transplantation: The Improving Renal Outcomes Collaborative

There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes.     

Lower material stiffness in rupture-repaired Achilles tendon during walking: transmission-mode ultrasound for post-surgical tendon evaluation

Purpose

This cross-sectional study used transmission-mode ultrasound to evaluate dynamic tendon properties during walking in surgically repaired and contralateral Achilles tendon (AT), with a median (range) post-operative period of 22 (4–58) months. It was hypothesised that the axial transmission speed of ultrasound (TSOU) during walking would be slower, indicating lower material stiffness in repaired compared with contralateral AT.

Methods

Ten patients [median (range) age 47 (37–69) years; height 180 (170–189) cm; weight 93 (62–119) kg], who had undergone open surgical repair of the AT and were clinically recovered according to their treating clinicians, walked barefoot on a treadmill at self-selected speed (1.0 ± 0.2 m/s). Synchronous measures of TSOU, sagittal ankle motion, vertical ground reaction force (GRF), and spatiotemporal gait parameters were recorded during 20 s of steady-state walking. Paired t tests were used to evaluate potential between-limb differences in TSOU, GRF, ankle motion, and spatiotemporal gait parameters.

Results

TSOU was significantly lower (≈175 m/s) in the repaired than in the contralateral AT over the entire gait cycle (P < 0.05). Sagittal ankle motion was significantly greater (≈3°) in the repaired than in the contralateral limb (P = 0.036). There were no significant differences in GRF or spatiotemporal parameters between limbs.

Conclusions

Repaired AT was characterised by a lower TSOU, reflecting a lower material stiffness in the repaired tendon than in the contralateral tendon. A lower material stiffness may underpin greater ankle joint motion of the repaired limb during walking and long-term deficits in the muscle-tendon unit reported with AT repair. Treatment and rehabilitation approaches that focus on increasing the material stiffness of the repaired AT may be clinically beneficial. Transmission-mode ultrasound would seem useful for quantifying tendon properties post AT rupture repair and may have the potential to individually guide rehabilitation programmes, thereby aiding safer return to physical activity.

Level of evidence

II.

     

Nitroglycerine reduces neutrophil activation and acute damage in latissimus dorsi muscle grafts

Background. Damage to the latissimus dorsi muscle (LDM) may jeopardize a successful outcome to dynamic cardiomyoplasty. We and others have demonstrated muscle damage in LDM in various species including humans. Ischemia is now recognized to be an important contributory factor. We postulated that glyceryl trinitrate, a nitric oxide donor, might protect against ischemic endothelial dysfunction and so reduce resultant muscle damage.

Methods. In 20 adult rats the left LDM was mobilized on its thoracodorsal neurovascular pedicle and maintained as an orthotopic graft. Half of the animals received glycerol trinitrate intraoperatively and postoperatively for 24 hours. The other half served as untreated controls. Each group was further subdivided into two groups (n = 5 in each): animals in which the LDM was excised after 4 hours for myeloperoxidase studies, and animals in which the LDM was excised at 24 hours for analysis of muscle damage by histology and enzyme macrohistochemistry. Blood samples were taken at 24 hours for assay of plasma nitrite and nitrate as nitric oxide metabolites.

Results. Glycerol trinitrate-treated animals had higher plasma nitric oxide metabolite levels after 24 hours (after nitrate reductase treatment, total nitrite, 78.3 ± 11.8 nmol/mL, mean ± SEM) than controls (42.1 ± 3.7 nmol/mL, p = 0.008). The proportion of viable LDM in glycerol trinitrate-treated animals was greater than in untreated animals, mainly in the middle and distal regions of the graft (middle region, 96.3% ± 0.5% versus 75.7% ± 4.1%, p < 0.001; distal region, 94.4% ± 0.8% versus 40.9% ± 3.1%, p < 0.001). Macrohistochemical findings correlated well with the histologic findings. Myeloperoxidase activity (U/g) was markedly lower in glycerol trinitrate-treated LDMs, mainly in the distal part of the graft (glycerol trinitrate versus control, 20.5 ± 2.1 versus 40.9 ± 3.1 U/g, p < 0.001).

Conclusions. Glycerol trinitrate significantly reduced acute damage to the distal two-thirds of the mobilized LDM, possibly by modifying leukocyte activation and endothelial dysfunction associated with ischemic injury.