Characteristics of urban natural areas influencing winter bird use in southern Ontario, Canada.

Characteristics of urban natural areas and surrounding landscapes were identified that best explain winter bird use for 28 urban natural areas in southern Ontario, Canada. The research confirms for winter birds the importance of area (size) and natural vegetation, rather than managed, horticultural parkland, within urban natural areas as well as percent urban land use and natural habitat in surrounding landscapes. Alien bird density and percent ground feeding species increased with percent surrounding urban land use. Higher percent forest cover was associated with higher percentages of forest, bark feeding, small (<20 g) and insectivorous species. Natural area size (ha) was related to higher species richness, lower evenness and higher percentages of insectivorous, forest interior, area-sensitive, upper canopy, bark feeding, and non-resident species. Higher number of habitat types within natural areas and percent natural habitat in surrounding landscapes were also associated with higher species richness. Common, resident bird species dominated small areas (<6.5 ha), while less common non-residents increased with area, indicative of a nested distribution. Areas at least 6.5 ha and more generally >20 ha start to support some area-sensitive species. Areas similar to rural forests had >25% insectivores, >25% forest interior species, >25% small species, and <5% alien species. Indicator species separated urban natural areas from rural habitats and ordination placed urban natural areas along a gradient between urban development and undisturbed, rural forests. More attention is needed on issues of winter bird conservation in urban landscapes.

The preparticipation sports examination for high school and college athletes.

The PSE can be used as a tool to allow athletes to participate safely in sports. The goal of the PSE is not to disqualify athletes but to ensure that their participation in sports does not unnecessarily increase their risk of injury. The PSE is most effectively conducted by the station method with multiple examiners, one of whom should have specialty training in musculoskeletal disorders. The examination should be conducted 6 weeks prior to the beginning of the season and at the beginning of each new level of competition, unless directed differently by local laws. The correct use of the PSE should screen for signs and symptoms of pathological states that may lead to a nontraumatic death while participating in sports. An effective musculoskeletal examination should detect any postinjury deficits that may lead to subsequent reinjury later in the season. It is our hope that a PSE, based on the literature, can be used to prevent some of the nontraumatic deaths and musculoskeletal injury associated with sports participation.

Fractures of the ipsilateral femur and tibia: emphasis on intra-articular and soft tissue injury.

Twenty-one patients with fractures of the ipsilateral femur and tibia were treated at Boston City Hospital from 1982 through 1987. Fourteen (67%) of the 21 patients sustained a total of 17 open fractures (76% of which were grade II or III wounds). Over 50% of the patients suffered concomitant ipsilateral knee injuries. Associated injuries required 37 nonorthopaedic procedures; 30 orthopaedic procedures were required to stabilize the axial skeleton and the other three extremities. Five patients ultimately required amputation, reflecting the magnitude of the initial high-energy trauma. Superior results were achieved when early rigid intramedullary fixation of the femur and rigid stabilization of the tibia with either an intramedullary nail or an external fixator was undertaken. Patients that underwent initial rigid intramedullary fixation of both the femur and tibia required fewer secondary operative procedures than those treated with primary external fixation. Rigid internal fixation allowed for thorough evaluation and treatment of the ligamentous structures of the knee and facilitated management of the soft tissue trauma.

Injury and disability in the professional athlete.

An injury at work affects the professional athlete more than his nonathlete counterpart because it may portend the end of his playing career. The pertinent issues that concern the injured athlete are initial assessment of the injury, regulations governing treatment and rehabilitation of the injury, criteria for return-to-play status, determination of permanent impairment, and the athlete's rights. Permanent impairment determination procedures and compensation mechanisms are well established in each of the major professional leagues in the United States.

Secondary reconstruction of the lateral ligaments of the ankle.

Due to the increased number of participants in athletic activities and because such people continue to participate for many years, secondary reconstructions of the lateral ligaments of the ankle are performed with greater frequency. Physical examination and review of the patient's history are of more value than stress X-rays of the tibiotalar joint in determining whether or not secondary reconstructive surgery is advisable. The modified Chrisman-Snook procedure presented reconstructs the anterior talofibular ligament and the calcaneofibular ligament, thereby reducing excessive subtalar motion. The results are predictable and appear to be lasting.

The augmentive use of methyl methacrylate in the management of pathologic fractures.

Methyl methacrylate is a useful adjunct to obtain secure internal fixation in the treatment of comminuted pathologic fractures. This method was used in 73 patients with 81 pathologic fractures of whom only four failed to regain function in the extremity which was operated upon. While it is probable that methyl methacrylate may have an adverse effect on fracture healing, the fixation achieved when applied to only one surface appears adequate and was observed to last for as long as nine years. The use of methyl methacrylate to augment internal fixation of pathologic fractures offers the patient a better chance to return to normal activities than any of the methods that are in use to date.