Introduction
Among the various hip fracture predictors explored to date, modifiable risk factors warrant special consideration, since they present promising targets for preventative measures. This ...systematic review and meta-analysis aims to assess various modifiable risk factors.
Material and methods
We searched four online databases in September 2017. We included studies that reported on modifiable lifestyle risk factors for sustaining fragility hip fractures. The quality of the included studies was assessed using the Newcastle–Ottawa Scale (NOS).
The inclusion criteria consisted of (1) adult patients with osteoporotic hip fracture, (2) original study, (3) availability of full text articles in English, and (4) report of a modifiable lifestyle risk factor.
Results
Thirty-five studies, containing 1,508,366 subjects in total, were included in this study. The modifiable risk factors that were significantly associated with an increased risk of hip fracture were the following: weight < 58 kg (128 lbs) (pooled OR 4.01, 95% CI 1.62–9.90), underweight body mass index (BMI) (< 18.5) (pooled OR 2.83, 95% CI 1.82–4.39), consumption of ≥ 3 cups of coffee daily (pooled OR 2.27, 95% CI 1.04–4.97), inactivity (pooled OR 2.14, 95% CI 1.21–3.77), weight loss (pooled OR 1.88, 95% CI 1.32–2.68), consumption of ≥ 27 g (approx. > 2 standard drinks) alcohol per day (pooled OR 1.54, 95% CI 1.12–2.13), and being a current smoker (pooled OR 1.50, 95% CI 1.22–1.85). Conversely, two factors were significantly associated with a decreased risk of hip fracture: obese BMI (> 30) (pooled OR 0.58, 95% CI 0.34–0.99) and habitual tea drinking (pooled OR 0.72, 95% CI 0.66–0.80).
Conclusion
Modifiable factors may be utilized clinically to provide more effective lifestyle interventions for at risk populations. We found that low weight and underweight BMI carried the highest risk, followed by high coffee consumption, inactivity, weight loss, and high daily alcohol consumption.
Abstract
Background
Knowledge regarding the biomechanics of the meniscus has grown exponentially throughout the last four decades. Numerous studies have helped develop this knowledge, but these ...studies have varied widely in their approach to analyzing the meniscus. As one of the subcategories of mechanical phenomena Medical Subject Headings (MeSH) terms, mechanical stress was introduced in 1973. This study aims to provide an up-to-date chronological overview and highlights the evolutionary comprehension and understanding of meniscus biomechanics over the past forty years.
Methods
A literature review was conducted in April 2021 through PubMed. As a result, fifty-seven papers were chosen for this narrative review and divided into categories; Cadaveric, Finite element (FE) modeling, and Kinematic studies.
Results
Investigations in the 1970s and 1980s focused primarily on cadaveric biomechanics. These studies have generated the fundamental knowledge basis for the emergence of FE model studies in the 1990s. As FE model studies started to show comparable results to the gold standard cadaveric models in the 2000s, the need for understanding changes in tissue stress during various movements triggered the start of cadaveric and FE model studies on kinematics.
Conclusion
This study focuses on a chronological examination of studies on meniscus biomechanics in order to introduce concepts, theories, methods, and developments achieved over the past 40 years and also to identify the likely direction for future research. The biomechanics of intact meniscus and various types of meniscal tears has been broadly studied. Nevertheless, the biomechanics of meniscal tears, meniscectomy, or repairs in the knee with other concurrent problems such as torn cruciate ligaments or genu-valgum or genu-varum have not been extensively studied.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The current understanding of glenohumeral joint stability is defined by active restrictions and passive stabilizers including naturally-occurring negative intraarticular pressure. Cadaveric specimens ...have been used to evaluate the role of intraarticular pressure on joint stability, although, while the shoulder's negative intraarticular pressure is universally acknowledged, it has been inconsistently accounted for.
During continuous, passive humeral abduction, releasing the native intraarticular pressure increases joint translation, and restoring this pressure decreases joint translations.
Descriptive Laboratory Study.
A validated shoulder testing system was used to passively abduct the humerus in the scapular plane and measure joint translations for seven (n = 7) cadaveric specimens. The pressure within the glenohumeral joint was measured via a 25-gauge needle during passive abduction of the arm, which was released and subsequently restored. During motion, the rotator cuff muscles were loaded using stepper motors in a force feedback loop and electromagnetic sensors were used to continuously measure the position of the humerus and scapula. Joint translation was defined according to the instant center of rotation of the glenohumeral head according to the recommendations by the International Society of Biomechanics.
Area under the translation versus abduction angle curve suggests that releasing the pressure within the capsule results in significantly less posterior translation of the glenohumeral head as compared to intact (85-90˚, p < 0.05). Posterior and superior translations were reduced after 70˚ of abduction when the pressure within the joint was restored.
With our testing system employing a smooth continuous passive motion, we were able to show that releasing intraarticular pressure does not have a major effect on the path of humeral head motion during glenohumeral abduction. However, both violating the capsule and restoring intraarticular pressure after releasing alter glenohumeral translations. Future studies should study the effect of simultaneous external rotation and abduction on the relationship between joint motion and IAP, especially in higher degrees of abduction.
Thoroughly simulating the glenohumeral joint environment in the cadaveric setting may strengthen the conclusions that can be translated from this setting to the clinic.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
Nonunion following treatment of supracondylar femur fractures with lateral locked plates (LLP) has been reported to be as high as 21 %. Implant related and surgeon-controlled ...variables have been postulated to contribute to nonunion by modulating fracture-fixation construct stiffness. The purpose of this study is to evaluate the effect of surgeon-controlled factors on stiffness when treating supracondylar femur fractures with LLPs:
Does plate length affect construct stiffness given the same plate material, fracture working length and type of screws?
Does screw type (bicortical locking versus bicortical nonlocking or unicortical locking) and number of screws affect construct stiffness given the same material, fracture working length, and plate length?
Does fracture working length affect construct stiffness given the same plate material, length and type of screws?
Does plate material (titanium versus stainless steel) affect construct stiffness given the same fracture working length, plate length, type and number of screws?
Methods
Mechanical study of simulated supracondylar femur fractures treated with LLPs of varying lengths, screw types, fractureworking lenghts, and plate/screw material. Overall construct stiffness was evaluated using an Instron hydraulic testing apparatus.
Results
Stiffness was 15 % higher comparing 13-hole to the 5-hole plates (995 N/mm849N vs. /mm,
p
= 0.003). The use of bicortical nonlocking screws decreased overall construct stiffness by 18 % compared to bicortical locking screws (808 N/mm vs. 995 N/mm,
p
= 0.0001). The type of screw (unicortical locking vs. bicortical locking) and the number of screws in the diaphysis (3 vs. 10) did not appear to significantly influence construct stiffness (
p
= 0.76,
p
= 0.24). Similarly, fracture working length (5.4 cm vs. 9.4 cm,
p
= 0.24), and implant type (titanium vs. stainless steel,
p
= 0.12) did also not appear to effect stiffness.
Discussion
Using shorter plates and using bicortical nonlocking screws (vs. bicortical locking screws) reduced overall construct stiffness. Using more screws, using unicortical locking screws, increasing fracture working length and varying plate material (titanium vs. stainless steel) does not appear to significantly alter construct stiffness. Surgeons can adjust plate length and screw types to affect overall fracture-fixation construct stiffness; however, the optimal stiffness to promote healing remains unknown.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Category:
Other
Introduction/Purpose:
Plantar fasciitis is the most common cause of heel pain in adults, affecting 1 out of 10 of the population at some point during their lifetime. Plantar specific ...stretching programs are popularity among foot and ankle surgeons consisting of passively dorsiflexing foot and using thumb to apply pressure. This technique is not without limitations. Certain patients are unable to properly perform the stretching techniques, such as limited mobility from advanced age, disability, or simply from performing stretching exercises incorrectly. The aims of this study are; first, identify what configuration of plantar-specific stretching combined with applied pressure to the plantar aponeurosis generates the greatest tensional force in the plantar fascia. And second, to construct a prototype device that could simulate these forces in a hands-free technique.
Methods:
Six (will be 10) fresh-frozen, morphologically normal cadaver feet (Medcure, RI) were utilized. Plantar fascia was exposed, ankle was fixed at 90-degree dorsiflexion using Calcaneo-Tibial Schanz Pin, specimen was then inverted and potted in a custom-made box (Smooth-Cast 300q, PA). Using an electromagnetic motion tracking system (Liberty, Polhemus, VT), the motion of sensors was recorded at 120 Hz. Utilizing tissue adhesive glue (Vetbond, 3M, Minnesota), the first sensor was attached to medial calcaneal tuberosity, and the second sensor was placed 5 cm distal to the first sensor on the plantar aponeurosis. Custom- built testing apparatus was made for induction of MTP dorsiflexion application of pressure on the plantar aponeurosis to mimic current conservative treatments. Weights were added to the custom build stretcher device in 10Lb increments. Strain percentage was calculated as the change in length divided by the baseline length position (condition 1) using the formula: (L − Lo/Lo) × 100
Results:
Dorsiflexion of 2nd-5th MTPs increases strain percentage more in comparison with 1st MTP dorsiflexion (Condition 3>4>2). This might show that dorsiflexing of 1st metatarsal is less effective at straining the plantar fascia because of the midfoot motion. By adding thumb pressure, strain percentages go higher, up to a point that in condition 7 (dorsiflexing all MTPs in combination of thumb pressure) it is significantly higher than our baseline condition (P=0.0385). It is noteworthy that, stretcher device itself (condition 8), cannot replicate conditions 4 or 7 strain percentages. When adding direct pressure and weight to the stretcher device (conditions 12 and 13), strains are even higher than condition 7 and also are significantly higher than the baseline (P= 0.0090 and 0.0291 respectively).
Conclusion:
The stretcher device itself is insufficient for stretching the plantar fascia, supporting the hypothesis of this study that we need a direct forceful pressure on the plantar aponeurosis as well. Our customized plantar stretcher not only can replicate the conventional stretching program, but also can produce higher strains on the plantar aponeurosis than the current manual application of plantar specific stretching. This device may impact the rehabilitation process in patients with advanced age as well as patients with spine mobility limitation who cannot perform manual stretching programs.
Category:
Ankle; Trauma
Introduction/Purpose:
There is a lack of consensus regarding optimal management of Posterior Malleolar Fractures (PMFs). Indirect reduction and fixation with ...posterior-anterior (PA) screw shows promise of avoiding the risks associated with direct reduction or indirect anterior to posterior (AP) approaches. Some authors have raised concerns about potential risk to nearby structures with PA technique, including hardware prominence into the syndesmosis. This study highlights the use of a posteromedial vertical syndesmotic line as a fluoroscopic landmark, helping surgeons avoid intra-syndesmotic placement.
Methods:
Indirect PA screw placement was completed on ten cadaveric specimens, followed by fluoroscopy in mortise and lateral views. Dissection was performed to assess screw placement relative to the posteromedial border of the syndesmosis. The posterior border of the syndesmosis was marked with a radiopaque wire. Repeat imaging was completed to validate the fluoroscopic posteromedial vertical syndesmotic line is representative of the posteromedial border of the tibial incisura.
Results:
On dissection, 9 of 10 cadavers had accurate screw placement with no penetration into the syndesmosis (Figure 1, bottom left & bottom right). Corresponding imaging showed the screw head to be medial to the marker on mortise view. For the specimen with penetration into the syndesmosis, imaging confirmed that the screw head was lateral to the marker on mortise views (Figure 1, top center & top right). The radiopaque marker correlated with the posteromedial vertical syndesmotic line for all specimens when comparing anatomic to radiographic findings. A radiographic safe zone is defined for the PA screw 12 mm medial to the vertical syndesmotic line to ensure no iatrogenic injury to the FHL tendon.
Conclusion:
This study demonstrated that the posterior incisura tibialis fluoroscopic landmark is unambiguous in localizing the posterior syndesmotic border (Figure 1, top left) and that screws medial to this line are safely out of the syndesmosis, while screws placed lateral are either in or at risk of intra-syndesmotic placement. A safe zone is defined for screw placement.
There is evidence of increased incidence, rapid progression, and poor prognosis of COVID‐19 in patients with underlying comorbidities such as diabetes and epilepsy. Developing effective treatment ...regimens for COVID‐19 patients with multiple comorbidities is crucial, as patients' past medical history is an essential contributor to possible organ injuries in COVID‐19 patients. Herein, we report a confirmed case of COVID‐19 patient with a history of multiple underlying diseases, including diabetes, epilepsy, and gout. The patient developed multiple organ failure and died a week after intensive care unit (ICU) admission. Multiple organ failure is the most common cause of death in COVID‐19 patients.
Developing effective treatment regimens for COVID‐19 patients with multiple comorbidities—especially diabetes and epilepsy—is crucial, as patients' past medical history is an essential contributor to possible organ injuries in COVID‐19 patients.
Substance administration to laboratory animals necessitates careful consideration and planning in order to enhance agent distribution while reducing any harmful effects from the technique. There are ...numerous methods for administering cannabinoids; however, several parameters must be considered, including delivery frequency, volume of administration, vehicle, and the level of competence required for staff to use these routes properly. There is a scarcity of information about the appropriate delivery method for cannabinoids in animal research, particularly those that need the least amount of animal manipulation during the course of the investigation. This study aims to assess the feasibility and potential side effects of intraperitoneal and subcutaneous injection of CBD and THC using propylene glycol or Kolliphor in animal models. By evaluating the ease of use and histopathological side effects of these solvents, this study intends to help researchers better understand an accessible long-term delivery route of administration in animal experiments while minimizing the potential confounding effects of the delivery method on the animal.
Intraperitoneal and subcutaneous methods of systemic cannabis administration were tested in rat models. Subcutaneous delivery via needle injection and continuous osmotic pump release were evaluated using propylene glycol or Kolliphor solvents. In addition, the use of a needle injection and a propylene glycol solvent for intraperitoneal (IP) administration was investigated. Skin histopathological changes were evaluated following a trial of subcutaneous injections of cannabinoids utilizing propylene glycol solvent.
Although IP delivery of cannabinoids with propylene glycol as solvent is a viable method and is preferable to oral treatment in order to reduce gastrointestinal tract degradation, it has substantial feasibility limitations. We conclude that subcutaneous delivery utilizing osmotic pumps with Kolliphor as a solvent provides viable and consistent route of administration for long-term systemic cannabinoid delivery in the preclinical context.
Hip fractures inflict heightened morbidity and mortality upon older adults. Although previous studies have explored the impact of individual demographic factors on hip fracture risk, a comprehensive ...review can help reconcile disparities among these factors. This meta-analysis encompassed 69 studies involving 976,677 participants and 99,298 cases of hip fractures. We found that age ≥ 85 (OR = 1.75), BMI < 18.5 (OR 1.72), female sex (OR = 1.23), history of falls (OR = 1.88), previous fractures (OR = 3.16), menopause (OR 7.21), history of maternal hip fractures (OR = 1.61), single and unmarried status (OR = 1.70), divorced status (OR 1.38), residing in a residential care facility (OR = 5.30), and living alone (OR = 1.47) were significantly associated with an increased incidence of hip fracture. Conversely, BMI ranging from 25 to 30 (OR = 0.59), BMI > 30 (OR = 0.38), parity (OR = 0.79), non-Caucasian descent (overall OR = 0.4, Asian OR 0.36, Black OR = 0.39, and Hispanic OR = 0.45), and rural residence (OR = 0.95) were significantly associated with a diminished risk of hip fracture. Hip fracture patients exhibited significantly lower weight and BMI than the non-fracture group, while their age was significantly higher. However, age at menopause and height did not significantly differ between the two groups.
Tendinopathy is a degenerative condition resulting from tendons experiencing abnormal levels of multi-scale damage over time, impairing their ability to repair. However, the damage markers associated ...with the initiation of tendinopathy are poorly understood, as the disease is largely characterized by end-stage clinical phenotypes. Thus, this study aimed to evaluate the acute tendon responses to successive fatigue bouts of tendon overload using an in vivo passive ankle dorsiflexion system.
Sprague Dawley female rats underwent fatigue overloading to their Achilles tendons for 1, 2, or 3 loading bouts, with two days of rest in between each bout. Mechanical, structural, and biological assays were performed on tendon samples to evaluate the innate acute healing response to overload injuries.
Here, we show that fatigue overloading significantly reduces
functional and mechanical properties, with reductions in hysteresis, peak stress, and loading and unloading moduli. Multi-scale structural damage on cellular, fibril, and fiber levels demonstrated accumulated micro-damage that may have induced a reparative response to successive loading bouts. The acute healing response resulted in alterations in matrix turnover and early inflammatory upregulations associated with matrix remodeling and acute responses to injuries.
This work demonstrates accumulated damage and acute changes to the tendon healing response caused by successive bouts of
fatigue overloads. These results provide the avenue for future investigations of long-term evaluations of tendon overload in the context of tendinopathy.
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