Searched for: in-biosketch:true
person:schonl01
Forefoot tendon transfers
Myers, Stuart H; Schon, Lew C
PMID: 21925362
ISSN: 1558-1934
CID: 3802572
Interdigital neuralgia
Peters, Paul G; Adams, Samuel B; Schon, Lew C
Interdigital neuralgia affects a significant number of individuals, with an average age of presentation in the sixth decade and a 4- to 15-fold increased prevalence in women. Historical descriptions date back to the 19th century. Nonoperative treatment with shoe modifications, metatarsal pads, and injections provides relief for most, but long term, 60% to 70% of patients eventually elect to have surgery. Although excision can be performed through a dorsal or plantar approach, we prefer the dorsal incision to prevent scar formation on the plantar aspect of the foot. Satisfactory results are common but not certain with reports of excellent or good ranging from 51% to 93%.
PMID: 21600450
ISSN: 1558-1934
CID: 3802532
Persistent or recurrent interdigital neuromas
Adams, Samuel B; Peters, Paul G; Schon, Lew C
Recurrent or persistent symptoms following surgical neurectomy for an interdigital neuroma are quite common, because of incorrect initial diagnosis, true neuroma formation, nerve stump adhesions, accessory nerve branches, or an adjacent web space neuroma. The clinical presentation of a recurrent neuroma is similar to the initial presentation. Recurrent symptoms usually occur within the first 12 months after surgery. The physical examination coupled with diagnostic nerve blocks is critical for diagnosis. Conservative therapy, although not particularly effective in treating true recurrent neuromas, may help to alleviate pain. With proper isolation of the instigating neuroma, revision surgical excision can be effective.
PMID: 21600451
ISSN: 1558-1934
CID: 3802542
3-Tesla magnetic resonance imaging evaluation of posterior tibial tendon dysfunction with relevance to clinical staging [Case Report]
Chhabra, Avneesh; Soldatos, Theodoros; Chalian, Majid; Faridian-Aragh, Neda; Fritz, Jan; Fayad, Laura M; Carrino, John A; Schon, Lew
The posterior tibial tendon (PTT) is the most important dynamic stabilizer of the medial ankle and longitudinal arch of the foot. PTT dysfunction is a degenerative disorder of the tendon, which secondarily involves multiple ligaments, joint capsules, fascia, articulations, and bony structures of the ankle, hindfoot, midfoot, and forefoot. When the tendon progressively attenuates, the patient develops a painful, progressive collapsed flatfoot or pes planovalgus deformity. This comprehensive review illustrates the 3-Tesla magnetic resonance imaging (3T MRI) features of PTT dysfunction. In addition, the reader will gain knowledge of the expected pathologic findings on MRI, as they are related to clinical staging of PTT dysfunction.
PMID: 21459628
ISSN: 1542-2224
CID: 3802512
Lateral process talus fracture in a kayaking injury [Case Report]
Yan, Alan Y; Mesfin, Addisu; Schon, Lew C
PMID: 21469617
ISSN: 1938-2367
CID: 3802522
Periarticular locking plate vs intramedullary nail for tibiotalocalcaneal arthrodesis: a biomechanical investigation
Ohlson, Blake L; Shatby, Meena W; Parks, Brent G; White, Kacey L; Schon, Lew C
Augmented retrograde intramedullary (IM) nail fixation was compared with augmented periarticular locking- plate fixation for tibiotalocalcaneal arthrodesis. Specimens in 10 matched pairs were randomly assigned to a fixation construct and loaded cyclically in dorsiflexion. The groups did not differ in initial or final stiffness, load to failure, or construct deformation. No correlation was found between bone mineral density and construct deformation for either group. A humeral locking plate may be a viable alternative to an IM nail for tibiotalocalcaneal fixation in cases not amenable to IM nailing.
PMID: 21720594
ISSN: 1934-3418
CID: 3802552
Interleukins 4 and 13 modulate gene expression and promote proliferation of primary human tenocytes
Courneya, Jean-Paul; Luzina, Irina G; Zeller, Cynthia B; Rasmussen, Jeffrey F; Bocharov, Alexander; Schon, Lew C; Atamas, Sergei P
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-4Ralpha, IL-13Ralpha1 and IL-13Ralpha2, but not the common gamma-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.
PMCID:2893086
PMID: 20537133
ISSN: 1755-1536
CID: 3802502
Lateral Ankle Ligament Injuries in Athletes: Diagnosis and Treatment
Groth, Adam T.; Guyton, Gregory P.; Schon, Lew C.
Nonsurgical management is preferred in most ankle sprains, even in the athletic population. However, patients presenting with chronic lateral ankle instability refractory to an appropriate bracing and rehabilitation program may benefit from lateral ligament reconstruction. Recognition and management of other associated injuries or conditions is critical to a successful outcome. We present 2 surgical techniques for reconstruction of the lateral ankle ligaments in athletes. The periosteal flap augmentation of the modified Brostrom reconstruction should be considered for primary cases. Patients who have failed prior surgical reconstruction or have a systemic condition resulting in generalized ligamentous laxity may require further surgical augmentation with an anatomical allograft ligament reconstruction technique. Oper Tech Sports Med 18:18-26 (C) 2010 Elsevier Inc. All rights reserved. ISI:000276703600004
ISSN: 1060-1872
CID: 3803402
Assessment of the foot and ankle in elite athletes
Schon, Lew C
An accurate assessment of the foot and ankle problem in elite athletes is the foundation of a treatment plan and prognosis. The special pressures of professional sports, where managers, agents, and lawyers may be involved, makes a thorough assessment especially critical for sound decision-making. Evaluation includes taking a history of the acute and chronic condition, including mechanism, physical sensation at injury, compensatory stresses, and general medical review. The athlete is assessed physically in several different ways, including comprehensive focal examination and alignment in static and dynamic nonweight-bearing and weight-bearing modes. This comprehensive process is essential to accurate assessment.
PMID: 19440134
ISSN: 1538-1951
CID: 3802482
Melvin Jahss, MD (1921-2009) [Historical Article]
Schon, Lew C
PMID: 19356366
ISSN: 1071-1007
CID: 3802472