Droughts, floods and freshwater ecosystems : evaluating climate change impacts and developing adaptation strategies

Climate change is expected to have significant impacts on hydrologic regimes and freshwater ecosystems, and yet few basins have adequate numerical models to guide the development of freshwater climate adaptation strategies. Such strategies can build on existing freshwater conservation activities, and incorporate predicted climate change impacts. We illustrate this concept with three case studies. In the Upper Klamath Basin of the western USA, a shift in land management practices would buffer this landscape from a declining snowpack. In the Murray–Darling Basin of south-eastern Australia, identifying the requirements of flood-dependent natural values would better inform the delivery of environmental water in response to reduced runoff and less water. In the Savannah Basin of the south-eastern USA, dam managers are considering technological and engineering upgrades in response to more severe floods and droughts, which would also improve the implementation of recommended environmental flows. Even though the three case studies are in different landscapes, they all contain significant freshwater biodiversity values. These values are threatened by water allocation problems that will be exacerbated by climate change, and yet all provide opportunities for the development of effective climate adaptation strategies.

Primary hemiarthroplasty for treatment of proximal humeral fractures

Background: Primary hemiarthroplasty of the shoulder is used to treat complex proximal humeral fractures, although the reported functional results following this method of treatment have varied widely. The aim of this study was to prospectively assess the prosthetic survival and functional outcomes in a large series of patients treated with shoulder hemiarthroplasty for a proximal humeral fracture. By determining the factors that affected the outcome, we also aimed to produce models that could be used clinically to estimate the functional outcome at one year following surgery.

Methods: A thirteen-year observational cohort study of 163 consecutive patients treated with hemiarthroplasty for a proximal humeral fracture was performed. Twenty-five patients died or were lost to follow-up in the first year after treatment, leaving 138 patients who had assessment of shoulder function with use of the modified Constant score at one year postinjury.

Results: The overall rate of prosthetic survival was 96.9% at one year, 95.3% at five years, and 93.9% at ten years. The overall median modified Constant score was 64 points at one year, with a typically good score for pain relief (median, 15 points) and poorer scores, with a greater scatter of values, for function (median, 12 points), range of motion (median, 24 points), and muscle power (median, 14 points). Of the factors that were assessed immediately after the injury, only patient age, the presence of a neurological deficit, tobacco usage, and alcohol consumption were significantly predictive of the one-year Constant score (p < 0.05). Of the factors that were assessed at six weeks postinjury, those that predicted the one-year Constant score included the age of the patient, the presence of a persistent neurological deficit, the need for an early reoperation, the degree of displacement of the prosthetic head from the central axis of the glenoid seen radiographically, and the degree of displacement of the tuberosities seen radiographically.

Conclusions: Primary shoulder hemiarthroplasty performed for the treatment of a proximal humeral fracture in medically fit and cooperative adults is associated with satisfactory prosthetic survival at an average of 6.3 years. Although the shoulder is usually free of pain following this procedure, the overall functional result, in terms of range of motion, function, and power, at one year varies. A good functional outcome can be anticipated for a younger individual who has no preoperative neurological deficit, no postoperative complications, and a satisfactory radiographic appearance of the shoulder at six weeks. The results are poorer in the larger group of elderly patients who undergo this procedure, especially if they have a neurological deficit, a postoperative complication requiring a reoperation, or an eccentrically located prosthesis with retracted tuberosities.

Severe impacted valgus proximal humerus fractures : results of operative treatment

Background: The functional results associated with nonoperative treatment of severely impacted valgus fractures of the proximal part of the humerus are poor, and these injuries are difficult to treat with minimally invasive percutaneous fixation techniques. The aim of this study was to review the functional and radiographic results and complications of a new operative technique in a series of twenty-five patients.

Methods: Over a two-year period, we treated twenty-nine patients with a severely impacted valgus fracture of the proximal part of the humerus. Three patients were lost to follow-up and one died, leaving twenty-five patients who were available for the study. In all of the fractures, the head-shaft angle had been tilted into =160° of valgus and the greater tuberosity was displaced by >1 cm. All patients were treated with open reduction of the fracture, and the space created behind the humeral head was filled with Norian Skeletal Repair System (SRS) bone substitute. The fractures were stabilized with either screws or buttress plate fixation. Associated rotator cuff tears were repaired. All patients underwent functional outcome assessment with use of the Constant, DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores at one year, and twelve patients were followed for two years.

Results: All fractures united within the first year, all reductions were maintained, and no patient had signs of osteonecrosis of the humeral head on the latest follow-up radiographs. At one year, the median Constant score was 80 points and the median DASH score was 22 points. The functional results continued to be satisfactory in the twelve patients who were followed for two years. The results in our series were better than those achieved in studies of nonoperative treatment of similar fracture configurations. There were six clinically relevant complications, although none required a reoperation and all six patients had a satisfactory short-term functional outcome.

Conclusions: Internal fixation of severely impacted valgus fractures of the proximal part of the humerus, supplemented by Norian SRS bone substitute to fill the proximal humeral metaphyseal defect, produces good early functional and radiographic outcomes. Additional follow-up will be required to assess whether these initially satisfactory outcomes are maintained over the longer term.

Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Severely impacted valgus proximal humeral fractures : surgical technique

Background: The functional results associated with nonoperative treatment of severely impacted valgus fractures of the proximal part of the humerus are poor, and these injuries are difficult to treat with minimally invasive percutaneous fixation techniques. The aim of this study was to review the functional and radiographic results and complications of a new operative technique in a series of twenty-five patients.

Methods: Over a two-year period, we treated twenty-nine patients with a severely impacted valgus fracture of the proximal part of the humerus. Three patients were lost to follow-up and one died, leaving twenty-five patients who were available for the study. In all of the fractures, the head-shaft angle had been tilted into > or = 160 degrees of valgus and the greater tuberosity was displaced by >1 cm. All patients were treated with open reduction of the fracture, and the space created behind the humeral head was filled with Norian Skeletal Repair System (SRS) bone substitute. The fractures were stabilized with either screws or buttress plate fixation. Associated rotator cuff tears were repaired. All patients underwent functional outcome assessment with use of the Constant, DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores at one year, and twelve patients were followed for two years.

Results: All fractures united within the first year, all reductions were maintained, and no patient had signs of osteonecrosis of the humeral head on the latest follow-up radiographs. At one year, the median Constant score was 80 points and the median DASH score was 22 points. The functional results continued to be satisfactory in the twelve patients who were followed for two years. The results in our series were better than those achieved in studies of nonoperative treatment of similar fracture configurations. There were six clinically relevant complications, although none required a reoperation and all six patients had a satisfactory short-term functional outcome.

Conclusions: Internal fixation of severely impacted valgus fractures of the proximal part of the humerus, supplemented by Norian SRS bone substitute to fill the proximal humeral metaphyseal defect, produces good early functional and radiographic outcomes. Additional follow-up will be required to assess whether these initially satisfactory outcomes are maintained over the longer term.

Surgical treatment of lateral clavicle fractures associated with complete coracoclavicular ligament disruption: clinico-radiological outcomes of acromioclavicular joint sparing and spanning implants

Distal clavicle fracture associated with complete coracoclavicular ligament disruption represents an unstable injury, and osteosynthesis is recommended. This study was performed (1) to retrospectively analyse the clinico-radiological outcomes of two internal fixation techniques, and (2) to identify and analyse radiographic fracture patterns of fracture that are associated with this injury. Conclusions: Internal fixation of this fracture pattern is associated with a high union rate and favorable clinical outcomes with both techniques. A combination of distal radius plate and ligament reconstruction device resulted in stable fixation and significantly lower reoperation rates, and should be used when fracture geometry permits (Types 1 and 2).

Fixed-angle locking proximal humerus plate: an evaluation of functional results and implant-related outcomes

Background
Displaced and unstable proximal humeral fractures are challenging injuries to treat. Proximal humeral locking plates are a recent development for the treatment of these complex fractures.

Methods
Retrospective analysis of 23 patients with 23 proximal humeral fractures treated with the Synthes locking proximal humerus plate. These were Neer two-, three- and four-part fractures. Follow-up was at a mean of 22 months and included clinical assessment using the Constant score (CS) and the Short Form-12 health questionnaire. Radiographic assessment was performed to assess implant-related complication in relation to the initial fracture pattern and the presence of adequate medial support.

Results
The mean CS for all patients was 60.4 (range, 29–85). The mean adjusted CS was 82% (range, 30–117), active forward flexion 127 degrees and the active abduction 115 degrees. Initial fracture pattern, the presence or absence of adequate medial support and age did not significantly influence the clinical scores. Complications included one infection, two cases of avascular necrosis, two cases of varus collapse with screw penetration and one non-union. The overall reoperation rate was 26%. There was an increased rate of complications in those with inadequate medial support (P = 0.0183) and a trend to higher complication rates in four-part fractures.

Conclusion
Using the locking proximal humerus plate for the treatment of proximal humeral fractures is an acceptable procedure with comparable outcomes with historical controls, but with a complication rate of 30%. More important than implant selection, however, is the ability to achieve a stable reduction with calcar support.