Size-Up, Size-Down: Accuracy of Component Sizing with Computerized Tomography and Robotic-Assisted Total Knee Arthroplasty.

Templating prior to total knee arthroplasty (TKA) can help to improve surgical efficiency and potentially improve alignment and outcomes. The purpose of this article is to evaluate the ability of computed tomography (CT)-based preoperative templating to accurately predict implant sizes. A total of 724 Stryker MAKO robotic-assisted TKA cases were retrospectively evaluated from a prospectively collected database between January 2020 and October 2023.

Virtual range of motion is a safe and acceptable alternative to intra-operative manual range of motion testing in direct anterior robotic total hip arthroplasty.

Introduction: In robotic total hip arthroplasty (THA), virtual range of motion (VROM) modeling allows the surgeon to account for spinopelvic motion and create an impingement-free range of motion that is patient-specific. The primary purpose of this study was to evaluate the risk of dislocation in patients undergoing direct anterior THA using VROM rather than manual ROM trialing.

Methods: Prospectively collected data was reviewed retrospectively of all consecutive anterior THAs performed by a single fellowship-trained surgeon.

Patient-Specific Venous Thromboembolic Event Prophylaxis in Total Joint Arthroplasty - Literature-Supported Guidelines.

Following total joint arthroplasty (TJA), venous thromboembolic events (VTE) are a known complication that may result in increased hospitalization cost as well as morbidity. Numerous investigations have documented patient-specific factors that place an individual at increased risk of VTE after TJA. Potential risk factors for VTE include genetic predisposition, history of a prior VTE event, revision surgery and patient comorbidity factors.

Looking beyond leaves: variation in nutrient leaching potential of seasonal litterfall among different species within an urban forest.

Unlabelled: Urban litterfall that is deposited on impervious surface leaches nutrients into stormwater, contributing to downstream eutrophication. Previous studies have focused on the leaching potential of deciduous leaf litter, while other smaller-volume litterfall types-such as blossoms and fruit-may leach significant amounts of nitrogen, phosphorus, and carbon. These additional litterfall types represent an unaccounted-for source of nutrients to urban stormwater.

Heterotopic Ossification Following Direct Anterior Total Hip Arthroplasty With and Without Postoperative Analgesic Nonsteroidal Anti-inflammatories.

Background: Heterotopic ossification (HO) can result in poorer clinical outcomes following total hip arthroplasty (THA). Multiple modes of intervention have been evaluated for HO prevention, including the use of nonsteroidal anti-inflammatories. Additionally, multimodal pain management strategies including celecoxib have become more prominent.

Differences in morphological and physiological plasticity in two species of first-year conifer seedlings exposed to drought result in distinct survivorship patterns.

First-year tree seedlings represent a critical demographic life stage, functioning as a bottleneck to forest regeneration. Knowledge of how mortality is related to whole-seedling carbon and water relations is deficient and is required to understand how forest compositions will be altered in future climatic conditions. We performed a greenhouse drought experiment using first-year seedlings of two common pine species found in the Intermountain West, USA.

Large variation in branch and branch-tip hydraulic functional traits in Douglas-fir (Pseudotsuga menziesii) approaching lower treeline.

Few studies have quantified intraspecific variation of hydraulic functional traits in conifers across elevation gradients that include range boundaries. In the Intermountain West, USA, the lower elevational limit of forests (lower treeline) is generally assumed to be caused by water limitations to growth and water relations, yet few studies directly show this. To test this assumption, we measured changes in a suite of traits that characterize drought tolerance such as drought-induced hydraulic vulnerability, hydraulic transport capacity and morphological traits in branch tips and branches of Douglas-fir (Pseudotsuga menziesii var.

Snowmelt Timing Regulates Community Composition, Phenology, and Physiological Performance of Alpine Plants.

The spatial patterning of alpine plant communities is strongly influenced by the variation in physical factors such as temperature and moisture, which are strongly affected by snow depth and snowmelt patterns. Earlier snowmelt timing and greater soil-moisture limitations may favor wide-ranging species adapted to a broader set of ecohydrological conditions than alpine-restricted species. We asked how plant community composition, phenology, plant water relations, and photosynthetic gas exchange of alpine-restricted and wide-ranging species differ in their responses to a ca.

A multi-species synthesis of physiological mechanisms in drought-induced tree mortality.

Widespread tree mortality associated with drought has been observed on all forested continents and global change is expected to exacerbate vegetation vulnerability. Forest mortality has implications for future biosphere-atmosphere interactions of carbon, water and energy balance, and is poorly represented in dynamic vegetation models. Reducing uncertainty requires improved mortality projections founded on robust physiological processes.

Ecotoxicological assessments show sucralose and fluoxetine affect the aquatic plant, Lemna minor.

Pharmaceuticals and personal care products (PPCP) are prevalent in aquatic systems, yet the fate and impacts on aquatic plants needs quantification for many compounds. We measured and detected sucralose (an artificial sweetener), fluoxetine (an antidepressant), and other PPCP in the Portneuf River in Idaho, USA, where Lemna minor (an aquatic plant in the environment and used in ecotoxicology studies) naturally occurs. Sucralose was hypothesized to negatively affect photosynthesis and growth of L.

Response of aboveground carbon balance to long-term, experimental enhancements in precipitation seasonality is contingent on plant community type in cold-desert rangelands.

Semi-arid rangelands are important carbon (C) pools at global scales. However, the degree of net C storage or release in water-limited systems is a function of precipitation amount and timing, as well as plant community composition. In northern latitudes of western North America, C storage in cold-desert ecosystems could increase with boosts in wintertime precipitation, in which climate models predict, due to increases in wintertime soil water storage that enhance summertime productivity.

Erratum to: Clinical Results and Failure Mechanisms of a Nonmodular Constrained Knee Without Stem Extensions.

[This corrects the article DOI: 10.1007/s11420-012-9277-9.].

Vegetation-zonation patterns across a temperate mountain cloud forest ecotone are not explained by variation in hydraulic functioning or water relations.

Many studies have demonstrated linkages between the occurrence of fog and ecophysiological functioning in cloud forests, but few have investigated hydraulic functioning as a determining factor that explains sharp changes in vegetation. The objective of this study was to compare the plant water status during cloud-immersed and non-immersed conditions and hydraulic vulnerability in branches and roots of species across a temperate, mountain fog ecotone. Because cloud forests are often dark, cool and very moist, we expected cloud forest species to have less drought-tolerant characteristics (i.

Linking carbon and water relations to drought-induced mortality in Pinus flexilis seedlings.

Survival of tree seedlings at high elevations has been shown to be limited by thermal constraints on carbon balance, but it is unknown if carbon relations also limit seedling survival at lower elevations, where water relations may be more important. We measured and modeled carbon fluxes and water relations in first-year Pinus flexilis seedlings in garden plots just beyond the warm edge of their natural range, and compared these with dry-mass gain and survival across two summers. We hypothesized that mortality in these seedlings would be associated with declines in water relations, more so than with carbon-balance limitations.

Lower limb alignment control: is it more challenging in lateral compared to medial unicondylar knee arthroplasty?

Introduction: Limb alignment after unicondylar knee arthroplasty (UKA) has a significant impact on outcomes. The literature lacks lateral UKA alignment studies, making our understanding of this issue based on medial UKA.

Methods: We evaluated limb alignment in 241 patients who underwent medial (229 knees) or lateral (37 knees) UKA.

Cruciate-retaining TKA is an option in patients with prior patellectomy.

Background: The recommendation for using posterior-stabilized (PS) implants in patellectomy patients undergoing total knee arthroplasty (TKA) is based on older case series with heterogeneous patient populations. The use of cruciate-retaining implants in these patients has not been evaluated with more contemporary implant designs.

Questions/purposes: The purpose of this study was to evaluate the survivorship and functional outcomes (Knee Society score, presence of an extensor lag, and range of motion) of cruciate-retaining (CR) TKA in patients with prior patellectomy.

The management of extensor mechanism complications in total knee arthroplasty. AAOS exhibit selection.

Complications involving the knee extensor mechanism and patellofemoral joint occur in 1% to 12% of patients following total knee arthroplasty and have major negative effects on patient outcomes and satisfaction. The surgeon must be aware of intraoperative, postoperative, and patient-related factors that can increase the rate of these problems. This review focuses on six of the most commonly encountered problems: patellar tendon disruption, quadriceps tendon rupture, patellar crepitus and soft-tissue impingement, periprosthetic patellar fracture, patellofemoral instability, and osteonecrosis of the patella.

Plasma 25-hydroxyvitamin d levels in operative patella fractures.

Background: Patella fractures have not traditionally been considered "fragility" fractures.

Questions/purpose: The purpose of this study was to examine the demographic patterns (age and gender distribution) and plasma 25-hydroxyvitamin D levels of a cohort of patients with operative patella fractures.

Patients And Methods: Medical records were reviewed on all consecutive patients presenting to our institution with operative patella fractures from 2003 to 2009.

Intraarticular analgesia versus epidural plus femoral nerve block after TKA: a randomized, double-blind trial.

Background: Pain management after TKA remains challenging and the efficacy of continuously infused intraarticular anesthetics remains a controversial topic.

Questions/purposes: We compared the side effect profile, analgesic efficacy, and functional recovery between patients receiving a continuous intraarticular infusion of ropivacaine and patients receiving an epidural plus femoral nerve block (FNB) after TKA.

Methods: Ninety-four patients undergoing unilateral TKA were prospectively randomized to receive a spinal-epidural analgesic infusion plus a single-injection FNB or a spinal anesthetic plus a continuous postoperative intraarticular infusion of 0.

Clinical results and failure mechanisms of a nonmodular constrained knee without stem extensions.

Introduction: In the setting of persistent knee instability despite appropriate ligament balancing for primary total knee arthroplasty, most surgeons advocate the use of an implant with increased articular constraint. These implants are commonly supplemented with stem extensions to improve stress transfer and decrease the risk of aseptic loosening. However, disadvantages exist with the use of stem extensions, including increased cost, intramedullary invasion, and diaphyseal pain.

Accelerometer-based, portable navigation vs imageless, large-console computer-assisted navigation in total knee arthroplasty: a comparison of radiographic results.

Computer-assisted surgery (CAS) systems improve alignment accuracy in total knee arthroplasty (TKA) but have not been widely implemented. Eighty knees underwent TKA using an accelerometer-based, portable navigation device (KneeAlign 2; OrthAlign Inc, Aliso Viejo, California), and the radiographic results were compared with 80 knees performed using a large-console, imageless CAS system (AchieveCAS; Smith and Nephew, Memphis, Tennessee). In the KneeAlign 2 cohort, 92.

Treatment of Lisfranc fracture-dislocations with primary partial arthrodesis.

Background: The optimal method of treatment for Lisfranc fracture-dislocations remains controversial, and the role of primary partial arthrodesis for combined osseous-ligamentous Lisfranc injuries is unclear. This study reviewed the outcomes of Lisfranc injuries treated by primary partial arthrodesis.

Methods: Patients who underwent primary partial arthrodesis for a primarily ligamentous or combined osseous and ligamentous Lisfranc fracture-dislocation were reviewed retrospectively and assessed at followup according to radiographic, clinical and standardized patient-based outcomes.

Surgical decision making for arthroscopic partial meniscectomy in patients aged over 40 years.

Purpose: To identify clinical variables that affect a surgeon's decision to recommend arthroscopic partial meniscectomy (APM).

Methods: Members of 2 orthopaedic specialty societies were invited to participate in an online survey by e-mail. The survey consisted of surgeon demographics and case scenarios to evaluate clinical decision making for APM.

Popliteal venotomy during posterior cruciate ligament reconstruction in the setting of a popliteal artery bypass graft.

Injury to the vascular structures in the popliteal fossa during arthroscopic cruciate ligament reconstruction can be limb threatening or even life threatening. We present the first report, to our knowledge, of an isolated injury to a popliteal vein during arthroscopic posterior cruciate ligament reconstruction. Unfortunately, the venotomy led to cardiopulmonary arrest and flash pulmonary edema in this patient.

An analysis of the hip and knee reconstruction section of the orthopaedic in-training examination.

This article analyzes the hip and knee reconstruction section of the Orthopaedic In-Training Examination (OITE). All of the hip and knee reconstruction questions from 2005 to 2009 were analyzed, and the following data were recorded: number of questions per year in the hip and knee section, total number of questions on the OITE per year, national average score by year in training, references cited, taxonomy classification of each question, topics that were tested, imaging modalities used for a given question, and treatment modalities tested. Eight percent to 9% of the questions on the OITE each year were hip and knee reconstruction-related questions.