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218


Intravenous administration of multipotent stromal cells and bone allograft modification to enhance allograft healing

Paudel, Sharada; Lee, Wen-Han; Lee, Moses; Zahoor, Talal; Mitchell, Reed; Yang, Shang-You; Zhao, Haiqing; Schon, Lew; Zhang, Zijun
AIM/OBJECTIVE:This study investigated a coordinated strategy of revitalizing bone allograft with circulating multipotent stromal cells (MSCs). MATERIALS & METHODS/METHODS:was implanted into the femur of athymic mice, which received intravenous injections of human MSCs or saline at weeks 1, 2 and 3. RESULTS: + MSC group (p < 0.05). CONCLUSION/CONCLUSIONS:Coating bone allograft with stromal cell-derived factor 1 and platelet-derived growth factor BB and intravenous injections of MSCs improved allograft incorporation.
PMID: 30761943
ISSN: 1746-076x
CID: 3803102

Compromised Antibacterial Function of Multipotent Stromal Cells in Diabetes

Cho, Young; Mitchell, Reed; Paudel, Sharada; Feltham, Tyler; Schon, Lew; Zhang, Zijun
In diabetes, multipotent stromal cells (MSCs) are functionally deficient. It is unknown, however, whether their antibacterial function is compromised. In this study, MSCs were isolated from the bone marrow samples provided by nine diabetic and six nondiabetic donors and treated with or without Escherichia coli lipopolysaccharides (LPS). The supernatant of diabetic MSCs (MSCs-dia) and nondiabetic control MSCs (MSCs-c) was added into the cultures of E. coli for evaluation of the effect of MSCs-dia and MSCs-c on bacterial growth. The number of E. coli colonies increased when they were cultured with the supernatant of MSCs-dia, with or without LPS stimulation, compared with the E. coli cultured with the supernatant of MSCs-c. Human macrophages were co-cultured with either MSCs-dia or MSCs-c, for 24 h, and then cultured with heat-inactivated E. coli. Bacterial phagocytosis was reduced after macrophages were co-cultured with MSCs-dia. Gene expression of antibacterial peptide LL-37 and indoleamine 2,3-dioxygenase (IDO) by MSCs-dia was reduced compared with MSCs-c. The supernatant of MSCs-dia and MSCs-c was applied to a 42-cytokine antibody array. While the cytokine profiles of MSCs-dia and MSCs-c were largely similar, the productions of MCP-1 and interleukin-6 distinguished MSCs-dia from MSCs-c in response to LPS treatment. In conclusion, MSCs-dia were less inhibitive of the growth of bacteria and compromised in regulation of macrophages for bacterial phagocytosis. The reduced expression of IDO and LL-37 and an altered cytokine profile in MSCs-dia should be taken into consideration in developing cell therapies for diabetic infection.
PMID: 30572796
ISSN: 1557-8534
CID: 3803092

Revision of the Failed Bunion Surgery

Sherman, Thomas I; Schon, Lew
Complications and failures of corrective surgery for hallux valgus are not infrequent, and their reported rates vary widely. This is at least partly because of the variety of surgical techniques performed as well as a lack of consensus regarding what constitutes a successful outcome. Some of the most commonly encountered reasons for failure include recurrence, hallux varus, nonunion, and malunion. These problems present a challenging scenario for both the patient and surgeon. A comprehensive understanding of these complications and a nuanced, critical analysis of each case is paramount to effective management of failed surgery for hallux valgus. There are several strategies for both minimizing complications in surgery for hallux valgus and salvaging a successful outcome through revision surgery.
PMID: 32032045
ISSN: 0065-6895
CID: 4373092

Clinical and radiographic outcomes of the Kramer osteotomy in the treatment of bunionette deformity

Lee, David C; de Cesar Netto, Cesar; Staggers, Jackson Rucker; Siegel, Rebecca; Chen, Richard; Bae, Su-Young; Schon, Lew C
BACKGROUND:Bunionette deformity is a painful bony prominence of the 5th metatarsal. We evaluated outcomes of using a Kramer osteotomy to treat this condition. METHODS:Retrospective study of patients treated with a Kramer osteotomy from 2003 and 2016. Outcome measures included Foot Functional Index (FFI) and radiographic measurements. RESULTS:angle improved 13.2° from 13.6° preoperatively to 0.4° at final follow-up (p<0.01). There were 5 delayed unions (11.6%) and 1 non-union (2.3%). CONCLUSIONS:angles and few complications.
PMID: 29409268
ISSN: 1460-9584
CID: 3803022

Metal Artifact Reduction Computed Tomography of Arthroplasty Implants: Effects of Combined Modeled Iterative Reconstruction and Dual-Energy Virtual Monoenergetic Extrapolation at Higher Photon Energies

Khodarahmi, Iman; Haroun, Reham R; Lee, Moses; Fung, George S K; Fuld, Matthew K; Schon, Lew C; Fishman, Elliot K; Fritz, Jan
OBJECTIVE:The aim of this study was to compare the effects of combined virtual monoenergetic extrapolation (VME) of dual-energy computed tomography data and iterative metal artifact reduction (iMAR) at higher photon energies on low- and high-density metal artifacts and overall image quality of the ankle arthroplasty implants with iMAR, weighted filtered back projection (WFBP), and WFBP-based VME. MATERIALS AND METHODS:Total ankle arthroplasty implants in 6 human cadaver ankles served as surrogates for arthroplasty implants. All specimens underwent computed tomography with a 2 × 192-slice dual-source computed tomography scanner at tube voltages of 80 and tin-filtered 150 kVp to produce mixed 120 kVp equivalent polychromatic and virtual monoenergetic extrapolated images at 150 and 190 keV (VME 150 and VME 190, respectively). By implementing the WFBP and iMAR reconstruction algorithms on polychromatic, VME 150 and VME 190 data, 6 image datasets were created: WFBP-Polychromatic, iMAR-Polychromatic, WFBP-VME 150, WFBP-VME 190, iMAR-VME 150, and iMAR-VME 190. High-density and low-density artifacts were separately quantified with a threshold-based computer algorithm. After anonymization and randomization, 2 observers independently ranked the datasets for overall image quality. Repeated measures analysis of variance, Friedman, and Cohen weighted κ tests were applied for statistical analysis. A conservative P value of less than 0.001 was considered statistically significant. RESULTS:iMAR-VME 190 keV and iMAR-VME 150 keV created the least amount of high-density artifacts (all P < 0.001), whereas iMAR-Polychromatic was the most effective method to mitigate low-density streaks (P < 0.001). For low- and high-density artifacts, polychromatic iMAR acquisition was superior to WFBP-VME 150 keV and WFBP-VME 190 keV (all P < 0.001). On sharp kernel reconstructions, readers ranked the overall image quality of iMAR-Polychromatic images highest (all P < 0.001). Similarly, on soft tissue kernel reconstructions, readers ranked iMAR-Polychromatic images highest with a statistically significant difference over other techniques (all P < 0.001), except for iMAR-VME 150 keV (P = 0.356). CONCLUSIONS:In computed tomography imaging of ankle arthroplasty implants, iMAR reconstruction results in fewer metal artifacts and better image quality than WFBP reconstruction for both polychromatic and virtual monoenergetic data. The combination of iMAR and VME at higher photon energies results in mixed effects on implant-induced metal artifacts, including decreased high-density and increased low-density artifacts, which in combination does not improve image quality over iMAR reconstruction of the polychromatic data. Our results suggest that, for ankle arthroplasty implants, the highest image quality is obtained by iMAR reconstruction of the polychromatic data without the need to implement VME at high-energy levels.
PMID: 30015677
ISSN: 1536-0210
CID: 3235062

Conservative Management and Biological Treatment Strategies: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle

Dombrowski, Malcolm E; Yasui, Youichi; Murawski, Christopher D; Fortier, Lisa A; Giza, Eric; Haleem, Amgad M; Hamid, Kamran; Tuan, Rocky; Zhang, Zijun; Schon, Lew C; Hogan, MaCalus V; [Kennedy, John G]
BACKGROUND:The evidence supporting best practice guidelines in the field of cartilage repair of the ankle are based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "Conservative Management and Biological Treatment Strategies" developed at the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS:Seventy-five international experts in cartilage repair of the ankle representing 25 countries and 1 territory were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 11 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed upon in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; unanimous, 100%. RESULTS:A total of 12 statements on Conservative Management and Biological Treatment Strategies reached consensus during the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. Ten statements reached strong consensus (greater than 75% agreement), and 2 achieved consensus. CONCLUSIONS:This international consensus derived from leaders in the field will assist clinicians with conservative management and biological treatment strategies for osteochondral lesions of the talus.
PMID: 30215314
ISSN: 1944-7876
CID: 3702632

Treatment With Autograft Interposition Arthroplasty in Advanced Hallux Rigidus

Orapin, Jakrapong; Schon, Lew C.
Hallux rigidus is a term that is used to describe restricted motion of the hallux metatarsophalangeal (MTP) joint secondary to degenerative arthritis. In the early stages of disease, cheilectomy is recognized as the treatment of choice for improving joint motion and functional outcomes. Traditionally, arthrodesis has been employed for its benefit in reducing pain as well as for controlling deformity in advanced hallux rigidus by eliminating MTP joint motion. However, we present an alternative to fusion; an interposition arthroplasty technique using the dorsal MTP joint capsule and extensor hallucis brevis tendon as interposed tissues. This technique has demonstrated efficacy in reducing arthritic pain and improving bony contour via osteophyte debulking, all while preserving MTP joint motion in active patients. (C) 2018 Elsevier Inc. All rights reserved.
ISI:000434868500006
ISSN: 1048-6666
CID: 3803432

Safety of dorsolateral talonavicular joint fixation in modified double arthrodesis: an anatomic study

Atwater, Lara C.; Aynardi, Michael C.; Melvani, Roshan; Schon, Lew C.; Miller, Stuart D.
Background:
ISI:000435074900017
ISSN: 1940-7041
CID: 3803442

Metal artifact reduction MRI of total ankle arthroplasty implants

de Cesar Netto, Cesar; Fonseca, Lucas F; Fritz, Benjamin; Stern, Steven E; Raithel, Esther; Nittka, Mathias; Schon, Lew C; Fritz, Jan
OBJECTIVES/OBJECTIVE:To assess high-bandwidth and compressed sensing-(CS)-SEMAC turbo spin echo (TSE) techniques for metal artifact reduction MRI of total ankle arthroplasty (TAA) implants. METHODS:Following institutional approval and consent, 40 subjects with TAA implants underwent 1.5-T MRI prospectively. Evaluations included bone-implant interfaces, anatomical structures, abnormal findings and differential diagnoses before and after MRI. AUCs of P-P plots were used to determine superiority. Statistical differences were evaluated with McNemar and chi-square tests. P-values ≤ 0.05 were considered significant. RESULTS:CS-SEMAC TSE was superior to high-bandwidth TSE in showing the bone-implant interfaces (AUC=0.917), periprosthetic bone, tendons and joint capsule (AUC=0.337-0.766), bone marrow oedema (43 % difference, p=0.041), interface osteolysis (63 %, p=0.015), tendinopathy (62 %, p=0.062), periprosthetic fractures (60 %, p=0.250), synovitis (43 %, p=0.250), as well as reader confidence for bone marrow oedema (p=<0.001), fracture (p=0.001), interface osteolysis (p=0.003), synovitis (p=0.027) and tendinopathy (p=0.034). The number of differential diagnoses in symptomatic subjects after the MRI with CS-SEMAC decreased from 3 (1-4) to 1 (1-2) (p<0.001). CONCLUSIONS:MRI of TAA implants with CS-SEMAC improves the diagnosis of interface osteolysis, periprosthetic bone marrow oedema, fractures and tendinopathy when compared to high-BW TSE, and has a positive effect on patient management. KEY POINTS/CONCLUSIONS:• High-bandwidth TSE and compressed sensing SEMAC improve MRI of ankle arthroplasty implants. • Compressed sensing SEMAC improves bone-implant interfaces, periprosthetic bone, tendons and joint capsule visibility. • Compressed sensing SEMAC improves the diagnosis of osteolysis, tendinopathy, fractures and synovitis. • MRI decreases the number of clinical differential diagnoses of painful ankle arthroplasty implants.
PMID: 29218618
ISSN: 1432-1084
CID: 3802982

☆Diagnostic and therapeutic injections of the foot and ankle-An overview

de Cesar Netto, Cesar; da Fonseca, Lucas Furtado; Simeone Nascimento, Felipe; O'Daley, Andres Eduardo; Tan, Eric W; Dein, Eric J; Godoy-Santos, Alexandre Leme; Schon, Lew Charles
Foot and ankle injections are useful diagnostic and therapeutic tools, particularly when the pain etiology is uncertain. A variety of foot and ankle injuries and pathologies, including degenerative joint disease, plantar fasciitis and different tendinopathies are amenable to injections. Understanding the foot and ankle anatomical landmarks, a thorough physical exam and knowledge of the different injection techniques is key for a successful approach to different pathologies. The objective of this study is to review the use of foot and ankle injections in the orthopaedic literature, present the readers with the senior author's experience and provide a comprehensive clinical guideline to the most common foot and ankle diagnostic and therapeutic injections.
PMID: 29409219
ISSN: 1460-9584
CID: 3803012