title: Biodegradable device applied in flatfoot surgery: comparative studies between clinical and technological aspects of removed screws.
abstract: Poly-L-lactide (PLLA) is one of the most used polymers for biomedical application; its use in sutures and other implants has been widely investigated. Although the knowledge of PLLA biodegradation and biocompatibility features is deep, PLLA screws used to correct the flat foot deformity have deserved attention since they are not degraded in most of cases after a long period of years (3-7) from the implantation. In this article, a clinical and radiological evaluation (NMR, histological and clinical outcomes) on patients was correlated with physico-chemical characterization (by SEM, DSC, GPC and XRD analysis at different temperatures) on both native and patient-recovered screws together with the theoretical degradation processes of PLLA-based implants. The data demonstrated the need for crossing the biodegradation and bioabsorption of the polymer with the characteristics of both the device (geometry, structure and fabrication process) and the implantation site.
authors.affiliation: Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 183, 41100 Modena, MO, Italy. barbara.ruozi@unimore.it
authors.forename: Barbara
authors.initials: B
authors.lastname: Ruozi
authors.forename: Daniela
authors.initials: D
authors.lastname: Belletti
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Manfredini
authors.forename: Massimo
authors.initials: M
authors.lastname: Tonelli
authors.forename: Paola
authors.initials: P
authors.lastname: Sena
authors.forename: Maria Angela
authors.initials: MA
authors.lastname: Vandelli
authors.forename: Flavio
authors.initials: F
authors.lastname: Forni
authors.forename: Giovanni
authors.initials: G
authors.lastname: Tosi
mesh_terms: D020341:Absorbable Implants; D000042:Absorption; D000293:Adolescent; D001672:Biocompatible Materials; D001863:Bone Screws; D002152:Calorimetry, Differential Scanning; D002648:Child; D002850:Chromatography, Gel; D003460:Crystallization; D020878:Device Removal; D005260:Female; D005413:Flatfoot / Q000473:pathology / Q000601:surgery*; D006801:Humans; D007249:Inflammation / Q000473:pathology; D008297:Male; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D011091:Polyesters; D013052:Spectrometry, X-Ray Emission; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; C033616:poly(lactide)
keywords: Bioabsorption; Degradation time; Flatfoot; PLLA screws