Every month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.

This month, Matthew J. Allen, VetMB, PhD, author of the December 6, 2017 Specialty Update on Musculoskeletal Basic Science, summarized the five most compelling findings from among the more than 60 noteworthy studies summarized in the article.

Cartilage Repair

–Deriving induced pluripotent stem cells (iPSCs) from peripheral blood cells¹ rather than from dermal fibroblasts obviates the need for in vitro expansion. This method may also serve to boost interest in the use of commercial cell-based therapies with defined potency that are available off-the-shelf and don’t require separate cell-harvesting procedures.

–The FDA recommends that large-animal models be used to corroborate basic-science findings from small-animal models. Recent work has demonstrated the efficacy of insulin-like growth factor (IGF)-1 in supporting mechanically competent repair tissue following chondrocyte implantation in a pig model.²

Infection

–Infection, especially from organisms that have developed antimicrobial resistance and/or that produce biofilms, continues to pose a challenging problem for orthopaedic surgeons. To provide a more rational and stratified approach to managing these complex cases, Getzlaf et al. recommend the use of a multidisciplinary approach in which patient-specific information about individual microorganisms is combined with detailed understandings of the vulnerabilities of candidate bacterial species.³

Aseptic Loosening

–There is a resurgence of interest in the role of subclinical infection in the etiopathogenesis of aseptic loosening. At the same time, molecular diagnostic methods for microbial infection are moving forward.⁴ Such methods may serve to highlight the relevance of subclinical microbial contamination as a cause of aseptic loosening.

Cartilage Imaging

–While the goal of cartilage imaging is to develop tools that are fast, inexpensive, sensitive, accurate, and noninvasive, there is growing interest in the use of more direct, invasive techniques such as optical coherence tomography (OCT),⁵ which could be used in vivo at the time of surgery to analyze cartilage damage.

References

1. Li Y, Liu T, Van Halm-Lutterodt N, Chen J, Su Q, Hai Y. Reprogramming of blood cells into induced pluripotent stem cells as a new cell source for cartilage repair. Stem Cell Res Ther.2016 Feb 17;7:31.
2. Meppelink AM, Zhao X, Griffin DJ, Erali R, Gill TJ, Bonassar LJ, Redmond RW,Randolph MA. Hyaline articular matrix formed by dynamic self-regenerating cartilage and hydrogels. Tissue Eng Part A.2016 Jul;22(13-14):962-70. Epub 2016 Jul 7.
3. Getzlaf MA, Lewallen EA, Kremers HM, Jones DL, Bonin CA, Dudakovic A,Thaler R, Cohen RC, Lewallen DG, van Wijnen AJ. Multi-disciplinary antimicrobial strategies for improving orthopaedic implants to prevent prosthetic joint infections in hip and knee. J Orthop Res.2016 Feb;34(2):177-86. Epub 2015 Dec 29.
4. Palmer MP, Melton-Kreft R, Nistico L, Hiller NL, Kim LH, Altman GT, Altman DT, Sotereanos NG, Hu FZ, De Meo PJ, Ehrlich GD. Polymerase chain reaction-electrospray-time-of-flight mass spectrometry versus culture for bacterial detection in septic arthritis and osteoarthritis. Genet Test Mol Biomarkers.2016 Dec;20(12):721-31. Epub 2016 Oct 17.
5. Novakofski KD, Pownder SL, Koff MF, Williams RM, Potter HG, Fortier LA. High-resolution methods for diagnosing cartilage damage in vivo. 2016 Jan;7(1):39-51.