Comment on “efficacy of a single intra-articular injection of ultra-high molecular weight hyaluronic acid for hip osteoarthritis: a randomized controlled study”

We read with great interest the study by Clementi et al. that would like to explore the efcacy of a single intraarticular injection of ultra-high molecular weight hyaluronic acid in patients with hip osteoarthritis. Actually, we believe that investigating just patients’ clinical status using VAS and WOMAC scale should have been supported by further information. In fact, in order to have more data that could infuence the recent clinical practice, it is important to consider also  the efect that the intra-articular injection of ultra-high molecular weight hyaluronic acid could have on walking biomechanics using an objective measurement tool as gait analysis. In our opinion, the work by Clementi and colleagues is very important and useful especially for the long-term follow-up. Osteoarthritis is a theme currently representing a hot topic because the number of people afected by this pathology in the world is growing and this situation is a burden for healthcare system. Hence, modern medicine will meet, more and more, this issue. From this point of view, we believe that osteoarthritis management and rehabilitation should be performed by objectifying functional alterations using movement analysis instrumentations. The use of gait analysis should be desirable during diagnosis and follow-up . Gait analysis is able to assess diferent walking patterns in patient with osteoarthritis of the lower limbs, whereas the radiology can evaluate the status of the joint’s structures. Moreover, gait analysis  allows to identify the precise altered sub-phase of the walking cycle, permitting adequate prescription of a rehabilitation protocol, giving to the clinician information about kinematic and kinetic alterations and also about the muscle activity. Finally, gait analysis is easily applicable to the most of patients, without side efects. Hence, this tool is ideal for repetitive follow-up evaluations and allows assessing any variations of walking biomechanics over time. Furthermore, gait analysis examinations could represent very valid outcome measurements in order  to understand the efcacy of injection therapy to treat hip osteoarthritis. These evaluations should be considered as a completion of clinical assessment, and their use should be always considered in rehabilitation of osteoarthritis.