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BackgroundAlthough the modified tension band technique (eg, tension band supplemented by longitudinal Kirschner wires) has long been the mainstay for fixation of transverse fractures of the patella, it has shortcomings, such as bad reduction, loosening of implants, and skin irritation.Questions/purposesWe conducted a retrospective comparison of the modified tension band technique and the titanium cable-cannulated screw tension band technique.Patients and MethodsWe retrospectively reviewed 101 patients aged 22 to 85 years (mean, 56.6 years) with AO/OTA 34-C1 fractures (n = 68) and 34-C2 fractures (n = 33). Fifty-two patients were in the modified tension band group and 49 were in the titanium cable-cannulated screw tension band group. Followup was at least 1 year (range, 1–3 years). Comparison criteria were fracture reduction, fracture healing time, and the Iowa score for knee function.ResultsThe titanium cable-cannulated screw tension band group showed improved fracture reduction, reduced healing time, and better Iowa score, compared with the modified tension band group. In the modified tension band group, eight patients experienced wire migration, three of these requiring a second operation. There were no complications in the titanium cable-cannulated screw tension band group.ConclusionsThe titanium cable-cannulated screw tension band technique showed superior results and should be considered as an alternative method for treatment of transverse patellar fractures.Level of EvidenceLevel III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Soil water is the key abiotic limiting factor in desert areas and hydrological processes determine the vegetation composition, patterns and processes in desert regions. The hydrological processes can be altered by vegetation succession. In this paper, we review the major advances in ecohydrological research and their potential impact on plant-water relations in revegetated desert communities. The major advances in ecohydrological research over the past 50 years in desert areas were analyzed using a case study that investigated the long-term ecosystem effects of sand-binding vegetation in the Tengger Desert. Key challenges and opportunities for ecohydrology research in the future are also discussed in the context of the major scientific issues affecting sand binding vegetation.

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km 2 in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed. desert areas, sand fixation by plant, succession of the artificial vegetation, soil water dynamics, carrying capacity for vegetation Citation:Li XR, Zhang ZS, Tan HJ, Gao YH, Liu LC, Wang XP. Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.

BackgroundThe incidence of intertrochanteric hip fracture is expected to increase as the global population ages. It is one of the most important causes of mortality and morbidities in the geriatric population. The incidence of reverse oblique and transverse intertrochanteric (AO/OTA 31-A3) fractures is relatively low; however, the incidence of implant failure in AO/OTA 31-A3 fractures is relatively high compared with that in AO/OTA 31-A1 and A2 fractures. To date, the risk factors for implant failure in AO/OTA 31-A3 fractures treated with proximal femoral nail antirotation (PFNA) have remained ambiguous. The purpose of this study was to identify the predictive factors of implant failure in AO/OTA 31-A3 fractures treated with PFNA.MethodsThe data of all patients who underwent surgery for trochanteric fractures at our institution between January 2006 and February 2018 were retrospectively reviewed. All AO/OTA 31-A3 fractures treated with PFNA were included. Logistic regression analysis of potential predictors of implant failure was performed. Potential predictors included age, sex, body mass index, fracture type, reduction method, status of posteromedial support and lateral femoral wall, reduction quality, tip-apex distance and position of the helical blade in the femoral head.ResultsOne hundred four (9.3%) patients with AO/OTA 31-A3 fractures were identified. Forty-five patients with AO/OTA 31-A3 fractures treated with PFNA were suitable for our study. Overall, implant failure occurred in six (13.3%) of forty-five patients. Multivariate analysis identified poor reduction quality (OR, 28.70; 95% CI, 1.91–431.88; p = 0.015) and loss of posteromedial support (OR, 18.98; 95% CI, 1.40–257.08; p = 0.027) as factors associated with implant failure.ConclusionsPoor reduction quality and loss of posteromedial support are predictors of implant failure in reverse oblique and transverse intertrochanteric fractures treated with PFNA.