Divergent spatio-temporal tree growth trends in Pinus pinaster Ait. in South-Western European forests.

Climate change influences forest ecosystems in several ways, such as modifying forest growth or ecosystem functionality. To fully understand the impact of changing climatic conditions on forest growth it is necessary to undertake long-term spatiotemporal analyses. The main purpose of this work is to describe the major trends in tree growth of Pinus pinaster in Spain over the last 70 years, differentiating homogeneous ecological units using an unsupervised classification algorithm and additive modelling techniques. We also aim to relate these growth trends with temporal series for precipitation and temperature, as well as forest variables. We leverage information from a large data set of tree cores (around 2200) extracted during the field campaign of the Fourth Spanish National Forest Inventory. An unsupervised algorithm classified the plots into five classes, which were consistent in ecological terms. We also found a general decline in growth in three of the five ecoregions since the 1970s, concomitant with an increase in temperature and a reduction in precipitation. However, this tree growth decline has not been observed in the Atlantic influenced ecoregion, where the cooler, more humid climatic conditions are more stable. Certain stand features, such as low basal area through forest management practices, may have alleviated the impact of harsh climatic conditions on some areas of inner Spain, while denser stands display a more pronounced decline in tree growth. We concluded that Southern populations show some degrees of growth decline and low growth trends while Northern populations did not exhibit growth decline and have the largest growth rates. Under a forecasted increment of temperatures, the growth decline can be expanded.

The Montecristo mining district, northern Chile: the relationship between vein-like magnetite-(apatite) and iron oxide-copper-gold deposits.

The Montecristo district, northern Chile, is one of the few places worldwide where there is a direct relationship between magnetite-(apatite) (MtAp) mineralization and iron oxide-copper-gold (IOCG) mineralization. The MtAp mineralization includes Ti-poor magnetite, fluorapatite, and actinolite and is crosscut and partially replaced by a younger IOCG mineralization that includes a second generation of actinolite and magnetite with quartz, chalcopyrite, pyrite, and molybdenite. The MtAp stage at Montecristo is interpreted as the crystallized iron-rich melts that used the pre-existing structures of the Atacama Fault System as conduits. These rocks later acted as a trap for hydrothermal IOCG mineralization. Geochronology data at Montecristo indicate that the host diorite (U-Pb zircon 153.3 ± 1.8 Ma, 2-sigma), MtAp mineralization (40Ar-39Ar in actinolite, 154 ± 2 Ma and 153 ± 4 Ma, 2-sigma), and the IOCG event (Re-Os on molybdenite, 151.8 ± 0.6 Ma, 2-sigma) are coeval within error and took place in a time span of less than 3.4 Ma. The εHfi and εNdi values of the host diorite are + 8.0 to + 9.8 and + 4.3 to + 5.4, respectively. The whole-rock 87Sr/86Sri values of the IOCG mineralization (0.70425 to 0.70442) are in the lower end of those of the MtAp mineralization (0.70426-0.70629). In contrast, εNdi values for the IOCG mineralization (+ 5.4 and + 5.7) fall between those of the MtAp rocks (+ 6.6 to + 7.2) and the host diorite, which suggests that the IOCG event was related to fluids having a more crustal Nd (εNdi < + 5.7) composition than the MtAp mineralization. This likely reflects the mixing of Nd from the MtAp protolith and a deep magmatic-hydrothermal source, very likely an unexposed intrusion equivalent to the host diorite. Sulfur isotope compositions (δ34S, + 0.3 to + 3.4‰) are consistent with a magmatic source. Supplementary Information: The online version contains supplementary material available at 10.1007/s00126-023-01172-0.

Elongation of the brachial plexus after reverse shoulder arthroplasty: an anatomical study.

INTRODUCTION: The use of reverse shoulder arthroplasty (RSA) is becoming more extended and its clinical results are good or excellent according to the literature. The main biomechanical characteristic of RSA is that it lowers and medializes the centre of rotation of the shoulder causing an arm lengthening. Although the number of neurological complications is low (5%), there are more neurophysiological changes in the brachial plexus with RSA than with the anatomic shoulder arthroplasty. The main goal of this study was to quantify the lengthening of the terminal branches of the brachial plexus suffered after RSA implantation. MATERIALS AND METHODS: 20 Embalmed cadavers were analysed. Four distances using bone references were employed to measure the lengthening of the arm and subacromial space. The brachial plexus and its terminal branches (radial, axillary, ulnar, musculocutaneous and median nerves) and the axillary artery, were identified and marked. Measurements were made to determine the change of position of the neurovascular structures, the arm lengthening and the lengthening of each nerve before and after the implantation of RSA. Two models of RSA were used: SMR®(Lima) and Delta Xtend®(DePuy-Synthes). RESULTS: The mean arm elongation was 10.5 mm. The subacromial space suffers an elongation of 20.5-29.8%. All the neurovascular structures suffered elongation: median nerve 23.1%, musculocutaneous nerve 22.1%, ulnar nerve 19%, radial nerve 17%, axillary nerve 12-14.5%, axillary artery 24.8%. There were no differences in the results between the types of prosthesis. CONCLUSIONS: Due to its design, the RSA causes an arm lengthening which is reflected by the elongation of the neurovascular structures of the arm.

Acute Carpal Tunnel Syndrome After Radial Artery Cannulation: A Case Report.

CASE: A 20-year-old postpartum woman developed paresthesias and intolerable pain over the volar aspect of the first through fourth fingers, after radial artery cannulation (RAC) during cesarean section. Ultrasonography did not show any hematoma in the forearm. Urgent carpal tunnel release and median nerve decompression were performed, resulting in complete disappearance of symptoms. CONCLUSION: Acute median nerve compression is a rare injury in its own, but it is even rarer as a complication of RAC. Urgent decompression should be performed as soon as possible to avoid future neurological deficits.

The triglyceride/glucose index as an insulin resistance marker in the pediatric population and its relation to eating habits and physical activity.

INTRODUCTION: To examine the triglyceride/glucose index (TyG) as an insulin resistance marker in obese children and adolescents and its relation to clinical and biochemical parameters, body composition and lifestyle. PATIENTS AND METHOD: Sixty patients aged 7-16 years of age were enrolled. Anthropometric variables were recorded, together with pubertal stage, blood pressure and body composition assessed by bioimpedance. The TyG index was calculated as ln (fasting glucose (mg/dL) × triglycerides (mg/dL))/2 and the HOMA (homeostatic model assessment) index as fasting insulin (µU/mL) × fasting glucose (mmol/L)/22.5. Feeding habits were documented by adherence to the Mediterranean dietary pattern questionnaire, while physical activity was assessed using the International Sedentary Assessment Tool (ISAT), as well as accelerometry (Actigraph wGT3X+). RESULTS: The mean TyG index was 4.45 ±â€¯0.18, and proved higher in the pubertal group. We found a positive correlation with the HOMA index (r = 0.39; P = 0.03) and TG/HDL-c index (r = 0.53; P < 0.001). The best cut-off point of the TyG index for predicting insulin resistance was 4.21 in prepubertal children (sensitivity 84%, specificity 100%; AUC: 0.84) and 4.33 in pubertal children (sensitivity 89%, specificity 69%; AUC: 0.61). A positive correlation was found with screen time (r = 0.39; P = 0.01), as well as a negative correlation with caloric expenditure (Kcal/day) in the prepubertal group (r = -0.81; P = 0.005). CONCLUSIONS: The TyG index could be a useful insulin resistance marker in the pediatric population. Moderate to vigorous physical activity should be encouraged, as well as restricting screen time for leisure purposes, mainly in the prepubertal group.

The triglyceride / glucose index as an insulin resistance marker in the pediatric population and its relation to eating habits and physical activity. / El índice triglicéridos-glucosa como marcador de insulinorresistencia en población pediátrica y su relación con hábitos de alimentación y actividad física.

INTRODUCTION: To examine the triglyceride/glucose index (TyG) as an insulin resistance marker in obese children and adolescents and its relation to clinical and biochemical parameters, body composition and lifestyle. PATIENTS AND METHOD: Sixty patients aged 7-16 years of age were enrolled. Anthropometric variables were recorded, together with pubertal stage, blood pressure and body composition assessed by bioimpedance. The TyG index was calculated as ln (fasting glucose (mg/dL)×triglycerides (mg/dL))/2 and the HOMA (homeostatic model assessment) index as fasting insulin (µU/mL)×fasting glucose (mmol/L)/22.5. Feeding habits were documented by adherence to the Mediterranean dietary pattern questionnaire, while physical activity was assessed using the International Sedentary Assessment Tool (ISAT), as well as accelerometry (Actigraph wGT3X+). RESULTS: The mean TyG index was 4.45±0.18, and proved higher in the pubertal group. We found a positive correlation with the HOMA index (r=0.39; P=.03) and TG/HDL-c index (r=0.53; P<.001). The best cut-off point of the TyG index for predicting insulin resistance was 4.21 in prepubertal children (sensitivity 84%, specificity 100%; AUC: 0.84) and 4.33 in pubertal children (sensitivity 89%, specificity 69%; AUC: 0.61). A positive correlation was found with screen time (r=0.39; P=.01), as well as a negative correlation with caloric expenditure (Kcal/day) in the prepubertal group (r=-0.81; P=.005). CONCLUSIONS: The TyG index could be a useful insulin resistance marker in the pediatric population. Moderate to vigorous physical activity should be encouraged, as well as restricting screen time for leisure purposes, mainly in the prepubertal group.

Reverse total shoulder arhroplasty for the treatment of failed fixation in proximal humeral fractures.

BACKGROUND: This study evaluates the clinical outcomes in patients with proximal humerus fractures (PHF) treated with reverse total shoulder arthroplasty (RTSA) as a revision procedure for failed fixation that have more than 5 years of follow-up. MATERIALS AND METHODS: This is a retrospective study of 270 RTSA. The inclusion criteria for this study consisted of patients initially treated with either open reduction and plate fixation (ORIF) or fixation using an intramedullary nail (IMN), who were managed with a single-stage revision to a RTSA, and had a minimum of 24 months clinical and radiological follow-up. Six patients with failed fixation of displaced PHF were revised with RTSA. One patient was excluded from the study because she died. Five shoulders were reviewed for the purpose of this study. The patients were evaluated using Constant score, relative Constant score and visual analogue scale for pain. RESULTS: The mean follow-up was 89 months (65-108). The mean absolute Constant score improved from 31, 81 to 44, 2 and the relative Constant score improved from 31,81% to 67,2%. Mean VAS improved from 6, 8 to 2. One patient rated their outcome excellent, 1good, 1 satisfied and 2 poor. CONCLUSION: RTSA is an appropriate treatment as a revision surgery for failed fixation of PHF. Patients should be adequately warned that they will improve their function but may have complications following this salvage procedure.

Spontaneous Fractures of a Modern Modular Uncemented Femoral Stem.

BACKGROUND: Femoral stem fracture following total hip arthroplasty is an uncommon event that requires immediate revision surgery. QUESTIONS/PURPOSES: We report on four patients who experienced stem fractures of one design and a review of the US Food and Drug Administration adverse event reports on this design. METHODS: Fracture surfaces of four EMPERION™ (Smith & Nephew, Memphis, TN) femoral stems were analyzed under optical and scanning electron microscopy. A search of the FDA's Manufacturer and User Facility Device Experience (MAUDE) that reports on all EMPERION™ adverse events was completed. RESULTS: Fracture surfaces exhibited characteristics consistent with a fatigue fracture mechanism. Sixteen MAUDE reports claimed stem fracture or breakage of EMPERION™ stems. CONCLUSION: The four cases of EMPERION™ stem fractures were likely driven by small stem diameter, high offset, and high patient weight. Modular stem-sleeve femoral systems are susceptible to fatigue failure under high stress and should only be used in appropriate patients, whom are not considered obese.

Topical Tranexamic Acid May Improve Early Functional Outcomes of Primary Total Knee Arthroplasty.

INTRODUCTION: The use of tranexamic acid (TXA) reduces postoperative anemia and blood transfusion requirements. We investigated if these beneficial effects improve the early outcomes of primary total knee arthroplasty (TKA). METHODS: We retrospectively studied 166 consecutive patients (179 TKAs) who received topical TXA (3 g before tourniquet deflation). This "study group" was compared with a "control group" of 197 consecutive patients (209 TKAs) in whom no TXA was used. We captured outcomes during the first 4 postoperative months. Knee Society score (KSS) was determined preoperatively, 6 weeks, and 4 months postoperatively. The outcomes were compared using univariate analysis. Multiple logistic regressions were calculated to assess differences between groups in KSS at 6 weeks and 4 months, controlling for age, sex, body mass index, and preoperative KSS. RESULTS: Postoperative hemoglobin was significantly higher in the study than that in the control group on day 1, day 2, and at discharge (P < .0001). Blood transfusions were required in 5% and 22% of patients (P < .001), respectively. Six weeks postoperatively, the functional KSS and its 5 categories (ability to walk, negotiate stairs up and down, stand up from a chair, and the use of support) were significantly higher in the study than those in the control group (P ≤ .001). Four months postoperatively, there was no difference in the KSS between the groups. DISCUSSION: Our study suggests that the clinical benefit of topical TXA administration extends beyond the hospitalization period. Its use may improve knee function during the first 6 postoperative weeks. This beneficial clinical effect seems to be negligible afterward.

Reverse shoulder arthroplasty for acute proximal humeral fractures in the geriatric patient: results, health-related quality of life and complication rates.

PURPOSE: Reverse shoulder arthroplasty (RSA) in fractures is especially indicated in patients of advanced age, although the influence of age on functional outcomes, health-related quality of life (HRQoL) and complication rate is unknown. We hypothesized that complication rate would decrease in the geriatric population because of their reduced activity, improving the perceived HRQoL. METHODS: Retrospective study of 42 patients with proximal humeral fractures treated with RSA, divided into two groups: <80 years (<80y)(n = 16) and ≥80 years (≥80y)(n = 26). The assessment tools used were radiological images (functional outcome) with the Constant-Murley score(CMS); disabilities of the arm, shoulder and hand (DASH) score; and HRQoL with the EQ-5D index. Mean follow-up time was 32.6 months. RESULTS: Mean CMS adjusted for age and sex (R-CMS) was 68 % ± 29 %. Patients in the ≥80y group had a lower total CMS, 33 vs 64 (p = 0.027). Mean active range of motion at 24 months <80y/≥80y was: forward flexion: 126°/110°; abduction: 117°/105°; external rotation: 22°/20°; and internal rotation: L3/sacrum. Mean EQ-VAS was 74 ± 16 in the <80y group, and 63 ± 12.6 in the ≥80y group. Mean DASH was 29.5 ± 9.2. The EQ-5D "self-care" item in the >80y group was the most affected. The "pain/discomfort" item was lower for the two age groups than for the reference population. There were 9.5 % complications: one prosthesis dislocation, one periprosthetic fracture and two surgical wound haematoma. CONCLUSIONS: Our results indicate that age is a critical factor for RSA success. Lower functional outcomes have been obtained in patients older than 80y, although the EQ-5D results in our sample were similar or even better than the referred population. LEVEL OF EVIDENCE: Level III.

Benefits of early intramedullary nailing in femoral metastases.

PURPOSE: Pathological fractures of the long bones are common complications of metastatic disease; however, the outcome of different surgical techniques for the treatment of these fractures has not been clearly defined. The aim of this study was to evaluate differences in prophylactic and therapeutic intramedullary nailing in femoral metastasic implants. METHODS: Sixty-five patients with metastasis of the femur were analysed retrospectively (37 females; 28 males) between 1995 and 2011 (follow-up 15 months). Forty-four presented with pathological fractures and 21 impending fractures (Mirel ≥7). The operative treatments used were intramedullary fixation with reamed long Gamma nails. The studied parameters were survival, radiological and analytical findings, and functional outcomes. RESULTS: Prophylactic nailing resulted in immediate postoperative deaths in 5% vs. 11.4% in therapeutic, and one technical complication was detected in each group. Among the surviving patients 75.9% of the fractures and 100 % of impending lesions were able to walk after the operation. The mean survival time was 11 months in the therapeutic (range 1-49) and 14 in the prophylactic group (1-34). The prophylactic intramedullary nails required a lower transfusion rate (1.4 concentrates vs. 3.0), mobilised earlier (day 4.0 vs. 9.7) and needed a shorter hospital stay (eight days vs. 16 days) compared to therapeutic nails (p < 0.05). CONCLUSION: Femoral intramedullary nailing of metastasic lesions provides satisfactory results both clinically and radiologically. Early treatment of the metastases prevents fractures and gives better results, improving life quality of these patients.