Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Nov;97(8):589-91.
doi: 10.1308/rcsann.2015.0044.

Determination of a safe INR for joint injections in patients taking warfarin

Affiliations

Determination of a safe INR for joint injections in patients taking warfarin

M A Bashir et al. Ann R Coll Surg Engl. 2015 Nov.

Abstract

Introduction: With an increase in life expectancy in 'developed' countries, the number of elderly patients receiving joint injections for arthritis is increasing. There are legitimate concerns about an increased risk of thromboembolism if anticoagulation is stopped or reversed for such an injection. Despite being a common dilemma, the literature on this issue is scarce.

Methods: We undertook 2,084 joint injections of the knee and shoulder in 1,714 patients between August 2008 and December 2013. Within this cohort, we noted 41 patients who were taking warfarin and followed them immediately after joint injection in the clinic or radiology department, looking carefully for complications. Then, we sought clinical follow-up, correspondence, and imaging evidence for 4 weeks, looking for complications from these joint injections. We recorded International Normalised Ratio (INR) values before injection.

Results: No complications were associated with the procedure after any joint injection. The radiologists who undertook ultrasound-guided injections to shoulders re-scanned the joints looking for haemarthroses: they found none. A similar outcome was noted clinically after injections in the outpatient setting.

Conclusion: With a mean INR of 2.77 (range, 1.7-5.5) and a maximum INR within this group of 5.5, joint injections to the shoulder and knee can be undertaken safely in primary or secondary care settings despite the patient taking warfarin.

Keywords: Complications; Injection; International Normalised Ratio; Warfarin.

PubMed Disclaimer

Figures

Figure 1
Figure 1
INR values and number of injections
Figure 2
Figure 2
Distribution of INR values in terms of time interval before injection

References

    1. Ouirke W, Cahill M, Perera K, Sargent J, Conway J. Warfarin prevalence indications for use and haemorrhagic events. Ir Med J 2007; : 402–404. - PubMed
    1. Grant PJ, Brotman M, Perera K. Perioperative anticoagulant management. Med Clin North Am 2009; : 1,105–1,121. - PubMed
    1. Thumboo J, O’Duffy JD. A prospective study of the safety of joint and soft tissue aspirations and injections in patients taking warfarin sodium. Arthritis Rheum 1998; : 736–739. - PubMed
    1. Salvati G, Punzi L, Pianon M. et al. . Frequency of the bleeding risk in patients receiving Warfarin submitted to arthrocentesis of the knee. Reumatismo 2003; : 159–163 [In Italian]. - PubMed
    1. Ahmed I, Gertner E. Safety of arthrocentesis and joint injection in patients receiving anticoagulation at therapeutic levels. Am J Med 2012; : 265–269. - PubMed

MeSH terms