Pragmatic controlled randomised trials aim to identify correlations between treatment and outcomes and thus seek to answer the question of “What works?” Functional disability and chronic knee pain are frequent in combats sports. In Brazilian Jiu-Jitsu practitioners (BJJPs) prevalence of lower limb injuries is high (45.7%). The objective of the study was to investigate the effectiveness of Mechanical Diagnosis and Therapy (MDT), through Directional Preference (DP), for specific functional disability in Brazilian Jiu-Jitsu practitioners (BJJPs) experiencing chronic non-specific knee pain. All participants reported having already received physical therapy resources in the last 12 months without satisfactory resolution for their Specific Functional Disability (SFD).

Inclusion criteria were male BJJPs between 20 to 40 years old, with chronic non-specific knee pain (above three months) who maintain a routine of at least two training sessions per week and had a minimum of four years Jiu-Jitsu (JJ) experience. Sixty-five BJJPs who volunteered and were evaluated according to MDT principles and concepts. Of these 28 (43%) were classified as DS with identified DPs (19 DS knee and 9 DS spine). These were then randomized pairwise into intervention (IG) and control (CG) groups.

Baseline data was collected at week 0, and then at weeks 6 and 10. Between weeks 0 and 6, the IG received the intervention DP following MDT and DP principles. Interventions were based on exercises and manual procedures consistent with their DP. The participants were precisely instructed on how to perform his exercise set autonomously comprising 6 to 10 sets of 10 movements, distributed throughout the day, totalling 60 to 100 repetitions per day. The CG was only followed up (wait-and-see). All participants (IG and CG) continued active participation in Jiu-jitsu training during the course of the study and follow up and were not required to decrease or interrupt the amount practice. Between weeks 6 and 10, both groups were only followed up to check for retention of any effect.

The primary outcome measure was the Patient Specific Function Scale (PSFS). Secondary outcomes were pain intensity (PI), identified via the numeric pain rating scale (NPRS) and fear-avoidance (FA) evaluated via the single hop test (SHT) utilising the lower limb symmetry index (LSI). Statistical analyses was performed by a blinded evaluator.

Results indicated that BJJPs with chronic knee pain, who were diagnosed with DS, the intervention, exercises and manual procedures in accordance with the participant's DP, resulted in greater improvements in SFD (with a large effect and PI (with a small effect), compared to the control group that was only followed (wait-and-see) for 6 and 10 weeks. In addition, improvement in the FA (LSI) was also found. These findings suggest that intervention based on DP may be effective short term in the management of chronic non – specific knee pain in BJJPs.

Relevance to MDT practitioners

This percentage 28/65 classified as DS (43%) supports MDT as a classification system informing effective management. The superior outcomes obtained by introducing exercises in accordance with the DP suggests further investigation with other extremity joints is warranted. The clinical efficacy demonstrated, posits DP as an effective low cost clinical tool whose full potential in the extremities has yet to be realised.

Extremities: Trials