Background Previous studies on tendinopathies of the hand (Quervain's tendinitis) and enthesis knee (anserine syndrome) have shown that some sort of ultrasound findings could predict the therapeutic response to specific treatments. Globally, acute inflammatory (power Doppler, synovial effusion) US findings predicts a better response to steroids injection than the chronic US findings (enthesophytosis, bone cortical irregularities).
Objectives The aim of present study is to determine the probability of therapeutical success of different treatment approaches according to the presence of some specific US findings, in patients with trochanteric pain.
Methods The image and clinical charts of patients who were assessed due to trochanteric pain between June 2015 and June 2016 in our clinic were reviewed. From those registries, dichotomic data about US findings were collected: Superficial bursitis, deep bursitis, cortical irregularities, enthesophytosis and power Doppler signal. The follow up data were collected from the electronic app or paper control form at day 6 to 9 from the original consultation. Successful treatment was interpreted as at least a reduction of 50% of the basal visual pain scale (rated from 1 to 10). Correlations with US findings were performed using single or composite variables.
Results One hundred and twenty six registries of patients with trochanteric pain were included. From all of them, 119 belongs to female patients (94.4%). The global US findings were as follows: 43 superficial bursitis, 39 deep bursitis, 47 cortical irregularities, 32 enthesophytosis and 6 power Doppler signal. Thirty seven steroids injection, 64 prescriptions of non steroideal antinflammatory drugs (NSAIDs) and 66 prescriptions of transdermal NSAIDs were performed.
Therapeutic success was achieved in 76.8% of patients who underwent an steroid injection in whom superficial or deep bursitis were identified in the US, and in 79.9% of patients who were treated with transdermal NSAIDs in whom enthesophytosis of cortical irregularities were identified.
By the other hand, patients treated with steroids injections in whom chronic US findings were achieved showed a failure treatment rate of 54.4%. For those in whom any kind of bursitis were identified the failure treatment rate of transdermal NSAIDs was 65.5%. Oral NSAIDs treatments were success in 35% of patients with any kind of bursitis and in 70% of patients with cortical irregularities or enthesophytosis.
Into the composite variables study we find that the treatment with steroid injection in patients with any kind of bursitis with independence of the presence of any chronic US findings had a Relative Risk (RR) of success of 2.66 compared to transdermal NSAID and a RR of 2.26 compared with oral NSAD treatment (P<0.001 y P<0.01, respectively). The only independent factor that demonstrated a 100% success treatment rate was the presence of power Doppler signal treated using steroid injection.
Conclusions US findings are useful predictors of therapeutic response in patients with trochanteric pain. In general terms, we found that patients with US acute findings have an increased probability of treatment success when treated with steroid injection while those with US chronic findings have an increased probability of success when treated with NSAIDs (transdermal or systemic).
Disclosure of Interest None declared