Joint injection practices in Pediatric Rheumatology - A global survey

Background: Intraarticular injections (IAI) were first reported in adult rheumatology in the 1950s and subsequently gained acceptance as a safe and efficacious treatment in Juvenile Idiopathic arthritis (JIA). IAIs are now widely performed and recommended as the initial or only treatment of Oligoarticular JIA and ancillary treatment of actively inflamed joints in other varieties of JIA. However, the performance of the procedure is not currently guided by standardized recommendations, thereby several practice variations are observed. Methods: This worldwide survey of pediatric rheumatologists (with 50% response from Pediatric Rheumatology International Trials Organization: PRINTO and Pediatric Rheumatology Collaborative Study Group: PRCSG members) captures the differences in pre-procedural, procedural and post procedural protocols observed across the globe and asks the necessity of developing consensus in this area of Pediatric Rheumatology. Results: This worldwide survey of Pediatric Rheumatologists had a response rate of almost 50% and captured the differences in IAI protocols observed across the globe. Conclusions: Consensus plans are needed to ensure uniformity in this widely used procedure in Pediatric Rheumatology.

In a survey about initial treatment for knee monoarthritis in JIA among Pediatric Rheumatologists in North America, 63% respondents believed that corticosteroid injections were more efficacious than Non-Steroidal Anti-inflammatory Drugs (NSAIDs) and 90% used NSAIDs as an initial or subsequent treatment strategy 4 . Despite the wide use of this procedure in chronic arthritis in children, there are no standard recommendations or guidelines on IAI practices in Pediatric Rheumatology.
We conducted a 22-item web-based survey to explore practice variations in pediatric IAI across the world. This survey was disseminated on Survey Monkey to PRCSG and PRINTO groups in North America and Europe respectively.

1.
To describe global variations in IAI practices.

2.
To explore the relation of these variations with physician demographic features.

Methods
Questionnaire design -A 22-item questionnaire comprising three main sections was designed. Section A pertained to questions regarding procedural variations viz setting of joint injection, number of joints injected, use of Ultrasound guidance, choice and dose of therapeutic agent, availability of TH, anesthesia preferences, complications, techniques for prevention of complications, and post procedure practices. Section B addressed variations in practice for patients less than 5 years of age and Section C was focused on physician demographic characteristics. The questionnaire was pilot tested by 3 pediatric rheumatologists prior to dissemination.
Subject selection -The survey link was disseminated via email to: PRCSG (n=169), and PRINTO/PRES members (n= 568) The survey was live for 2 months with one e-reminder sent at one month.

Results And Discussion
The response rate was 48.5% (358/737). 310/358 respondents (87%) routinely performed IAI in their clinical practice. The remaining 48 responses were excluded from the analysis.  Comments regarding availability of TH were: "advocacy to bring it back would be great", "Would like to use Aristospan (TH) but Kenalog (TA) is all we have available currently", and "Prefer TH but not available currently in US so use TA", indicating that availability of TH is perceived as a significant barrier in IAIs.
Small prospective trials and retrospective chart reviews have studied the efficacy of TA and TH in IAI and concluded that TH offers an advantage to TA, due to long duration of In a study by Eberhard et al from New York, 794 IAIs were examined of which 422 were injected with TH and 372 with TA. In this study, TH proved more effective than TA with respect to the time to relapse for first injection (p < 0.001) 9 .

Dose of steroid in TH equivalent:
The most used dose of steroid (TH equivalent) for large and small joint injections was 1 mg/kg and 0.5 mg/kg respectively (n=180:64% and n=155:55% respectively). While these are the recommended doses, several dose variations were observed in this response, ranging from 0.5mg/kg (n=24) to 2 mg/kg (n=28) with a minority using 1.5 mg/kg (n=12) for large joints (knees, shoulders and hips) and 0.25 mg/kg (n=42), 1 mg/kg (n=35) and 2 mg/kg (n=1) for small joints Additionally, short anesthesia (49%) and oral sedation (19%) were offered by most 6 respondents. A minority (2.13%) selected long anesthesia and amongst those who selected "Other" (30.85%) included no anesthesia, a mix of sedation and short anesthetic or differing choice as per age group.

Malleson et al explored anesthesia practices in pediatric joint injections in a Childhood
Arthritis & Rheumatology Research Alliance (CARRA) survey in 2010 and reported a lack of standard of care with respect to anesthetic practices in Pediatric Rheumatology 10 . In their study, 100% of respondents used some LA contrary to our results where more than 30% denied use of LA.

Complications and prevention:
IAI is a safe procedure without major systemic side effects. The incidence of reported complications ranges from 2.6% to 8.3% 6,11 . Some known minor complications of IAI include infections, skin atrophy, hypopigmentation, articular calcifications and avascular necrosis. 12,13 Similar complications were reported by the respondents in our survey (Table   1).
Techniques to prevent post-injection steroid leakage and subcutaneous atrophy included: reinjecting lidocaine (14.18%), quick withdrawal of needle (34.75%), combination of the above two (10.64%). 17% respondents reported no specific preventive measures. Amongst those who selected "other", application of pressure, injecting normal saline, physiological serum, bupivacaine, air, limiting the volume injected, Z-track method and pressure application after needle withdrawal were reported.
Post-procedure monitoring: Most respondents monitored the patient in the hospital until the effect of anesthesia subsided (77%). We are not aware of any pediatric studies that explore the benefit of a longer period of rest. In the adult literature, the period of post procedure rest ranges between 24-72 hours 14 and is reportedly controversial 15 .
Section B: Age-related practices 47% respondents followed significantly different practices for the <5year age group. Of these, the commonest age-dependent practice (72%) was choice of anesthesia. The CARRA survey 10 on anesthetic practices reported more use of LA in children > 8 years of age and general anesthesia in the younger age group. whereas none of those without formal training did. This difference was statistically significant with Fishers exact test (p<0.0001).