Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Andrew E. Federer is active.

Publication


Featured researches published by Andrew E. Federer.


Arthroscopy techniques | 2015

Capsular Suspension Technique for Hip Arthroscopy

Andrew E. Federer; Vasili Karas; Shane J. Nho; Struan H. Coleman; Richard C. Mather

Hip arthroscopy has recently become a common procedure to treat central and peripheral hip pathology. Capsulotomies are necessary in these procedures, and negotiating adequate visualization, as well as capsular preservation, is a challenge. We describe a capsular suspension technique that allows for adequate visualization of the central and peripheral compartments while facilitating preservation of the native hip capsule. This technique eliminates the need for additional personnel for retraction, potentially decreases iatrogenic hip injury, eliminates the need for excessive capsular debridement, and allows for capsular closure under minimal tension.


Foot & Ankle International | 2017

Hindfoot Arthritis Progression and Arthrodesis Risk After Total Ankle Replacement

Travis J. Dekker; David Walton; Emily N. Vinson; Kamran S. Hamid; Andrew E. Federer; Mark E. Easley; James K. DeOrio; James A. Nunley; Samuel B. Adams

Background: The purpose of this study was to assess the radiographic progression of subtalar and talonavicular degenerative joint disease in a series of patients who had undergone TAA (total ankle arthroplasty) with minimum follow-up of 5 years. Methods: TAA patient radiographs from a single institution were analyzed for peritalar arthritic changes by extrapolating the modified Kellgren Lawrence (KL) grades of the knee to the subtalar and talonavicular joints. Patients were included if they had a minimum of 5 years of follow-up. Patients who had undergone prior arthrodesis of the talonavicular or subtalar joints were excluded. A total of 140 patients with average follow-up of 6.5 years (range, 5.0-8.9 years) were included. Results: Overall, 27% of patients advanced 1 KL grade at the subtalar joint and 31% of patients increased 1 KL grade at the talonavicular joint. Furthermore, 60% and 66% of patients showed no progression in the subtalar and talonavicular joints, respectively. Two patients progressed greater than 2 KL subtalar arthritis grades and only 2 patients with talonavicular arthritis progressed to the same extent. Sixteen patients went on to require a subtalar arthrodesis compared to 2 requiring a talonavicular fusion (P < .05). Conclusion: This study suggests a moderate but nominal radiographic increase in adjacent subtalar and talonavicular arthritis over a minimum of 5 years after TAA. Future studies require a comparative control group of ankle fusion, but these data may suggest the motion preserved with an arthroplasty diminishes the stresses and compensatory motion incurred during tibiotalar arthrodesis. Level of Evidence: Level IV, retrospective case series.


Foot and Ankle Clinics of North America | 2017

Tendonitis and Tendinopathy: What Are They and How Do They Evolve?

Andrew E. Federer; John R. Steele; Travis J. Dekker; Jordan L. Liles; Samuel B. Adams

The development of tendinitis and tendinopathy is often multifactorial and the result of both intrinsic and extrinsic factors. Intrinsic factors include anatomic factors, age-related factors, and systemic factors, whereas extrinsic factors include mechanical overload and improper form and equipment. Although tendinitis and tendinopathy are often incorrectly used interchangeably, they are in 2 distinct pathologies. Due to their chronicity and high prevalence in tendons about the ankle, including the Achilles tendon, the posterior tibialis tendon, and the peroneal tendons, tendinitis and tendinopathies cause significant morbidity and are important pathologies for physicians to recognize.


Journal of Foot & Ankle Surgery | 2015

Blastomyces Tenosynovitis of the Foot and Ankle: A Case Report and Review of the Literature

Andrew E. Federer; Bryan D. Haughom; David M. Levy; Andrew J. Riff; Shane J. Nho

Deep fungal infection localized to the foot is not common, and when it occurs it often affects immunocompromised individuals. In this report, we describe the case of an adult diabetic patient who suffered with with Blastomycosis infection of the flexor digitorum longus and peroneal tendon sheaths. The condition was treated with systemic antifungal therapy and surgical debridement.


Hand | 2018

Open Reduction Internal Fixation With Transverse Volar Plating for Unstable Proximal Interphalangeal Fracture-Dislocation: The Seatbelt Procedure

Andrew E. Federer; Evan M. Guerrero; Travis J. Dekker; Suhail K. Mithani; J. Mack Aldridge; David S. Ruch; Marc J. Richard

Background: Unstable intra-articular proximal interphalangeal (PIP) joint fracture-dislocations present a difficult problem that requires congruous joint reduction and stable internal fixation or distraction. Though fractures with limited articular involvement may be treated successfully with less invasive procedures, fracture-dislocations with a volar shear component may benefit from joint reduction with subchondral support for maintenance of stability. The purpose of this article is to describe a volar transverse plate and screw technique and report the short-term postoperative results. Methods: Seventeen patients with volar shear PIP dorsal fracture-dislocations were treated with transverse plate and screw constructs at an average of 21 days (range, 2-52) after injury. Information on postoperative stability, range of motion at PIP and distal interphalangeal (DIP) joints, and radiographic outcomes and complications were retrospectively collected. Results: At a mean of 7.3 months post-operation (range, 1.5-24), there were no recurrent dislocations and an average PIP arc of 77.4° and DIP arc of 61.5°. Sixteen of 17 patients had radiographically concentric joints, with 1 patient showing slight radiographic dorsal subluxation not apparent clinically. Two of 17 patients (11.8%) had revision surgery for tenolysis and removal of hardware to improve range of motion at 4 and 9 months post-operation. Conclusions: In the setting of PIP dorsal fracture-dislocations with volar shear component >40% of the articular surface, the Seatbelt procedure allows for concentric joint and articular surface reduction with subchondral support for maintenance of stability. This volar transverse plating technique allows for highly functional range of motion without PIP dorsal subluxation clinically in the setting of comminution and delayed presentation.


Foot and Ankle Specialist | 2018

The Value of Motion: Patient-Reported Outcome Measures Are Correlated With Range of Motion in Total Ankle Replacement

Travis J. Dekker; Kamran S. Hamid; Andrew E. Federer; John R. Steele; Mark E. Easley; James A. Nunley; Samuel B. Adams

Background: The proposed benefit of total ankle replacement (TAR) over ankle fusion is preserved ankle motion, thus we hypothesized that an increase in range of motion (ROM) is positively correlated with validated patient-reported outcome measures (PROMs) in individuals receiving TAR. Methods: Patients undergoing TAR at a single academic medical center between 2007 and 2013 were evaluated in this study. In addition to a minimum of 2-year follow-up, complete preoperative and postoperative outcome measures for the Foot and Ankle Disability Index (FADI), Short Musculoskeletal Function Assessment (SMFA) Bother and Function Indices, Visual Analog Scale (VAS), and 36-Item Short Form Health Survey (SF-36) were requisite for inclusion. Standardized weightbearing maximum dorsiflexion and plantarflexion sagittal radiographs were obtained and previously described ankle and foot measurements were performed to determine ankle ROM. Results: Eighty-eight patients met inclusion criteria (33 INBONE, 18 Salto-Talaris, 37 STAR). Mean time to final ROM radiographs was 43.8 months (range 24-89 months). All aforementioned PROMs improved between preoperative evaluation and most recent follow-up ( P < .01). Final ankle ROM was significantly correlated with postoperative FADI, SF-36 Mental Component Summary (MCS), SMFA Bother and Function Indices, and VAS. Additionally, dorsiflexion was positively associated with FADI, SF-36 MCS, and SMFA Function ( P < .05) but plantarflexion had no such influence on outcomes. No differences were identified with subset stratification by prosthesis type, fixed versus mobile-bearing design or etiology. Conclusion: In this TAR cohort with prospectively collected outcomes data, radiographic sagittal plane ankle motion was positively correlated with multiple PROMs. Disease-specific and generic health-related quality of life PROMs demonstrated improvement postoperatively in all domains when evaluating final total range of motion. Patients who undergo TAR for end-stage osteoarthritis with improvement in ROM demonstrate a direct correlation with improved patient-centric metrics and outcome scores. Levels of Evidence: Level III: Retrospective comparative study


Foot & Ankle Orthopaedics | 2018

Osteochondral Lesions of the Talus: Current Concepts in Diagnosis and Treatment

John R. Steele; Travis J. Dekker; Andrew E. Federer; Jordan L. Liles; Samuel B. Adams; Mark E. Easley

Osteochondral lesions of the talus (OLTs) are a difficult pathologic entity to treat. They require a strong plan. Lesion size, location, chronicity, and characteristics such as displacement and the presence of subchondral cysts help dictate the appropriate treatment required to achieve a satisfactory result. In general, operative treatment is reserved for patients with displaced OLTs or for patients who have failed nonoperative treatment for 3 to 6 months. Operative treatments can be broken down into cartilage repair, replacement, and regenerative strategies. There are many promising treatment options, and research is needed to elucidate which are superior to minimize the morbidity from OLTs.


American Journal of Sports Medicine | 2018

Effects of Arthroscopy for Femoroacetabular Impingement Syndrome on Quality of Life and Economic Outcomes

Richard C. Mather; Shane J. Nho; Andrew E. Federer; Berna Demiralp; Jennifer Nguyen; Asha Saavoss; Michael J. Salata; Marc J. Philippon; Asheesh Bedi; Christopher M. Larson; J. W. Thomas Byrd; Lane Koenig

Background: The diagnosis and treatment of femoroacetabular impingement (FAI) have increased steadily within the past decade, and research indicates clinically significant improvements after treatment of FAI with hip arthroscopy. Purpose: This study examined the societal and economic impact of hip arthroscopy by high-volume surgeons for patients with FAI syndrome aged <50 years with noncontroversial diagnosis and indications for surgery. Study Design: Economic and decision analysis; Level of evidence, 2. Methods: The cost-effectiveness of hip arthroscopy versus nonoperative treatment was evaluated by calculating direct and indirect treatment costs. Direct cost was calculated with Current Procedural Terminology medical codes associated with FAI treatment. Indirect cost was measured with the patient-reported data of 102 patients who underwent arthroscopy and from the reimbursement records of 32,143 individuals between the ages of 16 and 79 years who had information in a private insurance claims data set contained within the PearlDiver Patient Records Database. The indirect economic benefits of hip arthroscopy were inferred through regression analysis to estimate the statistical relationship between functional status and productivity. A simulation-based approach was then used to estimate the change in productivity associated with the change in functional status observed in the treatment cohort between baseline and follow-up. To analyze cost-effectiveness, 1-, 2-, and 3-way sensitivity analyses were performed on all variables in the model, and Monte Carlo analysis evaluated the impact of uncertainty in the model assumptions. Results: Analysis of indirect costs identified a statistically significant increase of mean aggregate productivity of


Foot and Ankle Clinics of North America | 2017

Conservative Management of Metatarsalgia and Lesser Toe Deformities

Andrew E. Federer; David M. Tainter; Samuel B. Adams; Karl M. Schweitzer

8968 after surgery. Cost-effectiveness analysis showed a mean cumulative total 10-year societal savings of


Foot & Ankle International | 2017

Use of Patient-Specific 3D-Printed Titanium Implants for Complex Foot and Ankle Limb Salvage, Deformity Correction, and Arthrodesis Procedures:

Travis J. Dekker; John R. Steele; Andrew E. Federer; Kamran S. Hamid; Samuel B. Adams

67,418 per patient from hip arthroscopy versus nonoperative treatment. Hip arthroscopy also conferred a gain of 2.03 quality-adjusted life years over this period. The mean cost for hip arthroscopy was estimated at

Collaboration


Dive into the Andrew E. Federer's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Shane J. Nho

Rush University Medical Center

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Kamran S. Hamid

Rush University Medical Center

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge