Addition of a single ultrasound guided intra-articular injection of triamcinolone and lidocaine to advice and education for hip osteoarthritis (OA) was associated with greater improvement in hip pain and function over six months compared with advice and education alone, a UK study has found.

A total of 199 patients with hip OA, aged 40 years or over, with moderate to severe pain were recruited to the Hip Injection Trial (HIT) from orthopaedics, rheumatology, or two musculoskeletal interface services, as well as directly from general practice.

All patients had hip pain of at least six weeks’ duration, which had been present on most days in the past month. The mean age of participants was 62.8 years and 57% were women.

HIT was a pragmatic, three arm, parallel group, single blind, randomised controlled trial, conducted within two NHS community-based musculoskeletal services in England. Participants were allocated to one of three treatment arms:

• Advice and education. This consisted of written information (Versus Arthritis leaflet on OA), a bespoke leaflet on exercise and functional activities, and personalised advice and information about weight loss, exercise, footwear, walking aids, and pain management

• Advice and education plus ultrasound guided intra-articular hip injection of triamcinolone and lidocaine

• Advice and education plus ultrasound guided intra-articular hip injection of lidocaine

Pain and function

• Greater mean improvement in self-reported intensity of hip pain over six months (using a 0-10 Numerical Rating Scale) was reported with advice and education plus triamcinolone-lidocaine compared with advice and education alone: mean difference − 1.43 (95% CI: − 2.15 to − 0.72, P < 0.001); standardised mean difference − 0.55 (95% CI: − 0.82 to − 0.27).

There was also greater improvement in physical function: mean difference  between the groups in the SF-12 physical component scale score 3.80 (95% CI: 1.33-6.27).

• No significant difference in hip pain intensity over six months was reported between advice and education plus triamcinolone-lidocaine compared with advice and education plus lidocaine; mean difference between groups − 0.52 (95% CI: − 1.21 to 0.18). However, significantly better improvements in secondary outcomes e.g. quality of life, pain self-efficacy and physical function were seen in the former group.

• Ultrasound confirmed hip synovitis or effusion was associated with a significant interaction effect favouring advice and education plus triamcinolone-lidocaine − 1.70 (95% CI: − 3.10 to − 0.30).

 Patient satisfaction

At six months, participants in the advice and education plus triamcinolone-lidocaine arm compared with those receiving advice and education alone were:

• More likely to be satisfied with the treatment they had received (58% vs 34%); relative risk (RR) 1.72 (95% CI: 1.11-2.66), NNT = 4

• More likely to want the same treatment again (64% vs 34%); RR 1.89 (95% CI: 1.22-2.92), NNT= 3.

• At two months, they were also more likely to report that they were not limited in their usual activities because of hip pain (67% vs 45%); RR 1.79 (95% CI: 1.15-2.70), NNT= 3.

The study authors state:

‘In community settings of musculoskeletal services, we have shown that an ultrasound guided intra-articular hip injection of corticosteroid and local anaesthetic, administered with advice and education, is a clinically effective treatment for rapid and sustained symptom response compared with advice and education alone for people with hip osteoarthritis.’

The findings offer an important additional choice to patients, particularly those who are unsuitable for surgery or feel that their treatment options are limited.

Dr Jez Thompson