Anterior knee pain subgroups: the first step towards a personalized treatment

Identification of subgroups within the patellofemoral pain (PFP) population has gained a lot of interest and attention from the research community in recent years due to the recognition of the relatively poor patient outcomes associated with the multimodal approach and following the success of subgrouping approaches used in the management of low back pain. This paper reviews early attempts at PFP subgrouping and introduces readers to some of the modern methodological approaches employed to derive subgroups. Summaries of the results of two research projects illustrating the use of these more robust methods to derive subgroups in the PFP population are provided. In conclusion, it appears there are probably 3 or 4 discrete subgroups within the PFP population that may require a more personalised approach to treatment. However, to date no definitive randomized controlled trials (RCTs) have been conducted to evaluate the potential benefits of targeted interventions for PFP subgroups in terms of improved patient outcomes so this warrants further research.