Lew C. Schon

Dr. Lew C. Schon

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Research Focus & Metrics

Academic Career Length

29Years (1998-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2008 in Foot & Ankle International
Verified
Journal Article
Closed access
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POPatrick J. O'NEill
Patrick J. O'NEill
KLKevin J. Logel
Kevin J. Logel
BPBrent G. Parks
Brent G. Parks
LSLew C. Schon
Lew C. Schon
Background: Obtaining adequate fixation during tibiotalocalcaneal (TTC) arthrodesis may be challenging. Various fixation constructs have been tested biomechanically, but the use of a locking plate has not been reported. We hypothesized that the locking plate with a TTC augmentation screw would provide structural rigidity comparable to that of the intramedullary (IM) nail with a TTC augmentation screw during dorsiflexion testing. Materials and Methods: Six matched pairs of fresh frozen cadavers underwent TTC arthrodesis. Specimens in each pair were randomized to receive a locking plate or an intramedullary nail. Each specimen had an additional TTC augmentation screw through the calcaneus, talus, and medial tibia. All samples underwent dorsiflexion testing with determination of structural rigidity at the first cycle (initial rigidity) and last cycle (final rigidity) and the torque required to achieve a failure of 10 degrees of dorsiflexion. Statistical analysis was performed using a paired t-test to determine whether any differences were significant (p < 0.05). Results: The locking plate construct showed higher final rigidity (mean ± standard error of the mean) (27.7 ± 2.6 N-m/degree versus 17.6 ± 2.1 N-m/degree, p = 0.01) than the IM nail construct. There were no other differences measured. Conclusion: Rigidity with the the IM nail was inferior to that with locking plate fixation for TTC arthrodesis in one of the four parameters tested. Clinical Relevance: Screw augmented IM nail fixation and augmented locking plate fixation may offer similar rigidity clinically for TTC arthrodesis.

22 March 2015 in International Orthopaedics
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Journal Article
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BSBenjamin E. Stein
Benjamin E. Stein
DSDavid Alex Stroh
David Alex Stroh
LSLew C. Schon
Lew C. Schon

1 April 1998 in Clinical Orthopaedics and Related Research
Verified
Journal Article
Closed access
SWSteven B. Weinfeld
Steven B. Weinfeld
LSLew C. Schon
Lew C. Schon
Arthritis of the hallux metatarsophalangeal joint is a common disorder that affects shoewear, ambulation, and other activities of daily living. Etiologies include degenerative arthritis (hallux rigidus), crystal induced arthropathy (gout, pseudogout), rheumatoid arthritis, the seronegative spondyloathropathies, posttraumatic degeneration, and advanced hallux valgus. Accurate diagnosis and selection of the appropriate intervention depends on recognition of pertinent clinical and radiographic features. This study presents a synopsis of the senior author's (LCS) experience with 439 surgically treated patients with hallux metatarsophalangeal arthritis, focusing on origin and treatment.

10 June 2010 in Fibrogenesis & Tissue Repair
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Journal Article
Open access
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JCJean-Paul Courneya
Jean-Paul Courneya
ILIrina G Luzina
Irina G Luzina
CZCynthia B Zeller
Cynthia B Zeller
JRJeffrey F Rasmussen
Jeffrey F Rasmussen
ABAlexander Bocharov
Alexander Bocharov
SASergei Atamas
Sergei Atamas
Background: Tendon disorders (tendinopathies) pose serious biomedical and socioeconomic problems. Despite diverse treatment approaches, the best treatment strategy remains unclear. Surgery remains the last resort because of the associated morbidity and inconsistent outcomes. We hypothesized that, similar to fibroblasts in various organs, tendon fibroblasts (tenocytes) might be responsive to stimulation with interleukins (ILs), particularly IL-4 and IL-13. These two cytokines share sequence homology, receptor chains and functional effects, including stimulation of fibrogenesis. It is unknown whether tenocytes are responsive to stimulation with IL-4 or IL-13. If true, local use of these cytokines might be used to facilitate tendon repair in patients with tendinopathies or used for tendon tissue-engineering approaches to facilitate tenocyte growth on scaffolds in culture. Results: Tendon tissues that would normally be discarded were obtained during reconstructive surgery procedures performed for clinical indications. Primary tenocytes were derived from Achilles, posterior tibial, flexor digitorum longus and flexor hallucis longus tendon tissue samples. Reverse transcriptase quantitative PCR (RT-qPCR) experiments revealed that mRNAs for the receptor (R) chains IL-4Rα, IL-13Rα1 and IL-13Rα2, but not the common γ-chain were present in all tested tendon tissues and in cultured tenocytes. Levels of IL-13R chain mRNAs were significantly higher than those of IL-4R mRNA. The cultures responded, in a dose-dependent fashion, to stimulation with recombinant human IL-4 or IL-13, by increasing proliferation rates 1.5 to 2.0-fold. The mRNA levels of 84 genes related to cell cycle regulation were measured by RT-qPCR after 6 h and 24 h of activation. The expression levels of several genes, notably CDK6 and CDKN2B changed more than twofold. In contrast to their effects on proliferation, stimulation with IL-4 or IL-13 had little if any effect on the levels of collagen mRNA or protein in cultured primary tenocytes. The mRNA levels of 84 other genes related to extracellular matrix and cell adhesion were also measured by RT-qPCR; expression of only five genes was consistently changed. Conclusions: Stimulation with IL-4 or IL-13 could be used to facilitate tendon repair in vivo or to aid in tendon tissue engineering, through stimulation of tenocyte proliferation.

1 April 2018 in Foot and Ankle Surgery
Verified
Journal Article
Closed access
CNCesar De Cesar Netto
Cesar De Cesar Netto
LFLucas Furtado da Fonseca
Lucas Furtado da Fonseca
FNFelipe Simeone Nascimento
Felipe Simeone Nascimento
AOAndres Eduardo O’daley
Andres Eduardo O’daley
ETEric W. Tan
Eric W. Tan
LSLew C. Schon
Lew C. Schon

11 November 2024 in Foot & Ankle International
Verified
Journal Article
Closed access
AFAmanda N. Fletcher
Amanda N. Fletcher
JDJonathan Day
Jonathan Day
MMMorgan Motsay
Morgan Motsay
MMMaggie Manchester
Maggie Manchester
ZZZijun Zhang
Zijun Zhang
LSLew C. Schon
Lew C. Schon
Background: The Trabecular Metal Total Ankle Implant differs from other newer-generation implants in the transfibular approach, multiplanar external frame for alignment, tantalum trabecular metal interfaces, curved geometry, and shallow resection depths. The primary aim of this study was to report midterm clinical and radiographic results, as well as survivorship and adverse events at a minimum of 5-year follow-up. Methods: A total of 83 ankles (81 patients, average age 60.6 years old, 50.6% females) with average 6.3 years’ (range, 5.0-10.1) follow-up were included. Postoperative patient-reported outcome measures (PROMs) included SF-12 physical (PCS) and mental component summary (MCS) scores, Ankle Osteoarthritis Scale (AOS), pain visual analog scale (VAS). Radiographic outcomes included postoperative range of motion (ROM) and coronal/sagittal alignment. Adverse events were reported using the Canadian Orthopaedic Foot and Ankle Society Reoperation Coding System (CROCS). Results: Preoperative tibiotalar coronal deformity included 27 valgus (10 degrees, range 2-20 degrees) and 25 varus ankles (−9 degrees, range −2 to −25 degrees), corrected to neutral postoperatively. Postoperative tibiopedal ROM was 17.8 degrees dorsiflexion and 21.8 degrees plantarflexion. Adverse events occurred at average 28.7 months, most commonly gutter debridement (n = 17, 16.7%) and subsequent operative treatment unrelated to metal components (n = 10, 12.0%). There were 2 cases (2.4%) of acute deep infection treated with irrigation and debridement, polyethylene exchange, and retention of metal components without recurrence of infection. There were no cases of fibular nonunion, septic or aseptic loosening, or implant subsidence. Postoperative PROMS included SF-12 PCS: 40.4; SF-12 MCS: 56.0; VAS: 2.3; AOS Pain: 17.0; and AOS Disability: 24.9. Overall implant survival, defined by retention of the metal components, was 100% at final follow-up. Conclusion: At a minimum of 5 years, patients who underwent TM TAA reported minimal ankle pain and regained neutral ankle alignment and mobility, without septic or aseptic implant loosening. Although having certain limitations, this study suggests that TM TAA is a viable option for the treatment of end-stage ankle arthritis.