Understanding the Causes of Frailty Using a Life-Course Perspective: A Systematic Review

(1) Background: Few studies have examined risk factors of frailty during early life and mid-adulthood, which may be critical to prevent frailty and/or postpone it. The aim was to identify early life and adulthood risk factors associated with frailty. (2) Methods: A systematic review of cohort studies (of at least 10 years of follow-up), using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). A risk of confounding score was created by the authors for risk of bias assessment. Three databases were searched from inception until 1 January 2023 (Web of Science, Embase, PubMed). Inclusion criteria were any cohort study that evaluated associations between any risk factor and frailty. (3) Results: Overall, a total of 5765 articles were identified, with 33 meeting the inclusion criteria. Of the included studies, only 16 were categorized as having a low risk of confounding due to pre-existing diseases. The long-term risk of frailty was lower among individuals who were normal weight, physically active, consumed fruits and vegetables regularly, and refrained from tobacco smoking, excessive alcohol intake, and regular consumption of sugar or artificially sweetened drinks. (4) Conclusions: Frailty in older adults might be prevented or postponed with behaviors related to ideal cardiovascular health.

Increased hip flexion gait as an exercise modality for individuals with obesity

PURPOSE

Exercise is a critical element for the management of body weight and improvement of quality of life of individuals with obesity. Due to its convenience and accessibility, running is a commonly used exercise modality to meet exercise guidelines. However, the weight-bearing component during high impacts of this exercise modality might limit the participation in exercise and reduce the effectiveness of running-based exercise interventions in individuals with obesity. The hip flexion feedback system (HFFS) assists participants in meeting specific exercise intensities by giving the participant specific increased hip flexion targets while walking on a treadmill. The resulting activity involves walking with increased hip flexion which removes the high impacts of running. The purpose of this study was to compare physiological and biomechanical parameters during an HFFS session and an independent treadmill walking/running session (IND).

METHODS

Heart rate, oxygen consumption (VO2), heart rate error, and tibia peak positive accelerations (PPA) were investigated for each condition at 40% and 60% of heart rate reserve exercise intensities.

RESULTS

VO2 was higher for IND despite no differences in heart rate. Tibia PPAs were reduced during the HFFS session. Heart rate error was reduced for HFFS during non-steady state exercise.

CONCLUSION

While demanding lower energy consumption compared to running, HFFS exercise results in lower tibia PPAs and more accurate monitoring of exercise intensity. HFFS might be a valid exercise alternative for individuals with obesity or individuals that require low-impact forces at the lower limbs.

Utilizing Age-Predicted Heart Rate Maximum to Prescribe a Minimally Invasive Cycle Ergometer HIIT Protocol in Older Adults: A Feasibility Study

Previous research has provided evidence that aerobic HIIT exercise can induce important physiological adaptations and elicit improvements in health and fitness parameters. However, most of the research has taken place in a laboratory setting with specialized equipment and monitoring devices. It begs the question, is HIIT accessible to the general aging population? The objective of the current research was to employ an age-predicted HRmax to prescribe a minimally invasive 4x4 cycle ergometer HIIT protocol. Ten participants (age: 64.2 ± 6.1) completed a non-weight-bearing cycle ergometer protocol for 6 weeks. Significant Pearson correlations were found between %HRmax and W/kg in seven of the ten participants. Two participants showed significant correlations between RPE and W/kg. Half of the participants exhibited a significant correlation between %HRmax and RPE. Pre- to post-intervention measures demonstrated a significant increase in lower limb strength by the 10-repetition chair sit-to-stand (p = 0.004) and 30-second sit-to-stand (p = 0.021). Increased functional capacity demonstrated by TUG (p = 0.001) and SB (p = 0.034) also presented significant differences pre- to post-intervention. There was a 96% participant session completion rate. These data imply that a simple 4x4 cycle ergometer HIIT protocol prescribed using a %HRmax is effective at increasing lower-limb power/strength and can be used in the general older adult population without excessive oversight. Our intervention protocol demonstrates that 6 weeks of cycle ergometer HIIT is an adequate amount of time to result in lower limb strength and functional capacity improvements in active older adults.

Comparison of High-Intensity Interval Training to Moderate-Intensity Continuous Training in Older Adults: A Systematic Review

High-intensity interval training (HIIT) is emerging as a safe and effective means to combat chronic diseases. The objective of this work was to perform a systematic review of the effect of HIIT interventions in an aging population. Three electronic databases were searched for randomized trials comparing the effect of HIIT and moderate-intensity continuous training in older adults. After a thorough screening process, 15 articles were identified as meeting the inclusion criteria. All studies expressed a comparable or superior effect of HIIT in cardiorespiratory fitness measures. No studies reported a lessened effect of HIIT in comparison with moderate-intensity continuous training. This systematic review demonstrates that HIIT is a useful exercise regimen, which can be used in older adults to increase cardiorespiratory fitness. More research is needed to determine the effects of HIIT in an aging, predominately female population.

Results of surgical treatment for unstable distal clavicular fractures

HYPOTHESIS

Delayed surgical treatment of unstable distal clavicle fractures is associated with a higher complication rate.

MATERIALS AND METHODS

Between 1998 and 2008, a retrospective study of 38 patients (average age, 42.9 year) with Neer type II clavicular fractures was performed. Fractures were treated with a hook-plate (22 patients) or with superior locked plate with suture augmentation (16 patients). Patients were divided into acute (27 patients) or delayed (11 patients) treatment groups based on the timing of surgical intervention before or after 4 weeks. All had clinical and radiographic follow-up for 1 year or until fracture union.

RESULTS

Union was achieved in 36 of 38 patients (94.7%). The acute treatment group had an average American Shoulder and Elbow Surgeons score of 77.9 compared with 65.0 in the delayed group. Six complications occurred (15.8%) including 2 infections (5.3%), 1 hardware failure (2.6%), and 3 peri-implant fractures (7.9%). The complication rate was 36.4% in the delayed group vs 7.4% in the acutely treated group (P = .047).

DISCUSSION

A high rate of union was observed in all cases regardless of timing or method of fixation. Despite a high rate of union, the results of treatment in the delayed group were more problematic. Patients treated with a hook-plate in a delayed fashion had more complications than those treated in an acute fashion (P = .039). Peri-implant fractures occurred only in patients treated with hook-plates.

CONCLUSION

Surgical timing played a critical role in the outcome and complication rate in treatment of unstable distal third clavicle fractures.

Large coronal shear fractures of the capitellum and trochlea treated with headless compression screws

BACKGROUND

The purpose of this study is to retrospectively evaluate the clinical outcomes of 18 patients with large coronal shear fractures of the capitellum and lateral trochlea that underwent open reduction and internal fixation with headless compression screws.

METHODS

Eighteen patients were identified (16 women, 2 men) with an average age of 45 years and an average follow-up of 26 months. Fractures were classified according to the Dubberley classification as 11 type-1A injuries and 7 type-2A injuries.

RESULTS

All patients, with the exception of 1, had good to excellent functional results by the Broberg-Morrey scale (mean score, 93.3). Average arc of motion was 128 degrees in flexion/extension and 176 degrees in pronation/supination. Radiographically, 3 patients had subsequent development of avascular necrosis and 5 developed arthrosis. No significant negative correlation was noted between the development of avascular necrosis and clinical outcome. Minor complications occurred in 2 patients, but there were no re-operations.

CONCLUSION

Headless compression screw fixation allows for stable fixation in patients with large coronal shear fractures of the distal humerus without posterior comminution.

LEVEL OF EVIDENCE

4.

Characterization and expression of the Escherichia coli Mrr restriction system

The mrr gene of Escherichia coli K-12 is involved in the acceptance of foreign DNA which is modified. The introduction of plasmids carrying the HincII, HpaI, and TaqI R and M genes is severely restricted in E. coli strains that are Mrr+. A 2-kb EcoRI fragment from the plasmid pBg3 (B. Sain and N. E. Murray, Mol. Gen. Genet. 180:35-46, 1980) was cloned. The resulting plasmid restores Mrr function to mrr strains of E. coli. The boundaries of the mrr gene were determined from an analysis of subclones, and plasmids with a functional mrr gene produce a polypeptide of 33.5 kDa. The nucleotide sequence of the entire fragment was determined; in addition to mrr, it includes two open reading frames, one of which encodes part of the hsdR. By using Southern blot analysis, E. coli RR1 and HB101 were found to lack the region containing mrr. The acceptance of various cloned methylases in E. coli containing the cloned mrr gene was tested. Plasmid constructs containing the AccI, CviRI, HincII, Hinfl (HhaII), HpaI, NlaIII, PstI, and TaqI N6-adenine methylases and SssI and HhaI C5-cytosine methylases were found to be restricted. Plasmid constructs containing 16 other adenine methylases and 12 cytosine methylases were not restricted. No simple consensus sequence causing restriction has been determined. The Mrr protein has been overproduced, an antibody has been prepared, and the expression of mrr under various conditions has been examined. The use of mrr strains of E. coli is suggested for the cloning of N6-adenine and C5-cytosine methyl-containing DNA.