Timing of Intraarticular Hip Injection Changes Risk of Periprosthetic Joint Infection

Intraarticular (IA) injections are used in the diagnosis and treatment of degenerative joint disease. In some patients, these injections are part of a multimodal approach to the management of pain associated with osteoarthritis (OA). 

IA injections of corticosteroids exert potent anti-inflammatory effects mediated by direct action on nuclear steroid receptors, interrupting the inflammatory cascade and preventing further synthesis of mediators of inflammation such as prostaglandins and lekotrienes.¹  However, an increased risk of periprosthetic joint infection (PJI) has been reported with the preoperative administration of IA steroids.²  The development of PJI is an especially serious complication following total hip arthroplasty (THA), which can lead to implant failure and need for revision surgery.² Joint infection after IA injection is thought to occur via direct seeding of the joint, or as a result of corticosteroid immunosuppression. 

To investigate the risk of PJI after IA injection of the hip, researchers from the Hospital for Special Surgery in New York retrospectively analyzed the records of 196,521 patients from The Statewide Ambulatory Surgery and Inpatient Databases for Florida and California undergoing elective primary THA for indications other than traumatic hip fracture between 2005 and 2012. They identified patients who did not receive preoperative IA hip injections and those who did at 3 time frames prior to THA (12-18 weeks, 6-12 weeks, or 0-6 weeks).  They tracked PJI hospital readmission rates for a period of one year after primary THA.

Researchers found that patients who received preoperative IA hip injections within 12 weeks of THA had an increased incidence of PJI, according to the abstract presented at the 2016 annual meeting of the American Academy of Orthopaedic Surgeons (AAOS), in Orlando, Fla.³

Of the 196,521 patients analyzed, 3,688 (or 1.9%) received a preoperative IA hip injection. Of those patients, 1,268 patients received an IA hip injection 12-18 weeks prior to THA, 1,562 patients received an IA hip injection 6-12 weeks prior to THA 6-12 weeks, and 858 patients received an IA hip injection 0-6 weeks prior to THA.

In this study, the rate of PJI within one year of primary THA was 0.87% in patients who did not receive any preoperative IA hip injections. Among those patients who did receive IA hip injections, rates of PJI within one year were as follows:  0.87% in the 12-18 week group (HR=1.01, p=0.985), 1.34% in the 6-12 week group (HR 1.58, p=0.038), and 1.52% in the 0-6 week group (HR 1.76, p=0.042).

Summary and Clinical Applicability

The risk of deep joint PJI resulting from preoperative IA hip injections was evaluated in this large, population-level study. An increased rate of PJI was seen in patients who received IA hip injections within 12 weeks prior to undergoing THA.

The authors conclude that “THA should not be performed within three months of hip injection to avoid elevated risk of infection, but appears safe if performed more than three months pre-operatively”.

For generalizability purposes, it is important to note that this study excluded patients who underwent THA for the indication of hip fracture. These results were described in an abstract presented at the AAOS and have yet to be peer-reviewed prior to journal publication.

Due to this apparent increased infection risk, non-invasive treatments such as NSAIDS or mobility aids should be considered whenever possible, especially in patients deemed candidates for THA. 

Reference

1.  Ayhan E, Kesmezacar H, Akgun I. Intraarticular injections (corticosteroid, hyaluronic acid, platelet rich plasma) for the knee osteoarthritis. World J Orthop. 2014;5(3):351-61.

2.  Werner BC, Cancienne JM, Browne JA. The Timing of Total Hip Arthroplasty After Intraarticular Hip Injection Affects Postoperative Infection Risk. J Arthroplasty. 2015; pii: S0883-5403(15)00786-X. doi: 10.1016/j.arth.2015.08.032. [Epub ahead of print]

3.  Schairer WW, Nwachukwu BU, Lyman S, et al. Preoperative Hip Injections Increase the Rate of Periprosthetic Infection After Total Hip Arthroplasty. Abstract 916, presented at American Academy of Orthopaedic Surgeons annual meeting, Orlando, Fla. Mar 1, 2016.