Comparison of Pelvic Tilt Before and After Hip Flexor Stretching in Healthy Adults.

OBJECTIVE: The purpose of this study was to assess the association between hip flexor length and pelvic tilt or lumbar lordosis by quantifying the effect of stretching on pelvic tilt and lumbar lordosis. METHODS: We quantified pelvic tilt and lumbar lordosis before and after a single session of passive hip flexor stretching in a sample of 23 male participants. Changes in hip flexor length were also characterized, using a Thomas test protocol to measure passive hip extension in supine lying. We investigated both the mean effect of the stretching protocol and potential correlations between changes in passive hip extension and changes in pelvic tilt or lumbar lordosis. RESULTS: Following the stretching protocol, there was a mean increase of 2.6° (P < .001) in passive hip extension and a corresponding mean reduction of 1.2° (P < .001) in anterior pelvic tilt. However, there was no change in lumbar lordosis, nor were there any meaningful correlations between change in passive hip extension and change in pelvic tilt or lumbar lordosis. CONCLUSION: The results suggest that hip muscle stretching may lead to immediate reductions in pelvic tilt during relaxed standing. Such stretching programs could play an important role in interventions designed to improve standing postural alignment.

Reductions in co-contraction following neuromuscular re-education in people with knee osteoarthritis.

BACKGROUND: Both increased knee muscle co-contraction and alterations in central pain processing have been suggested to play a role in knee osteoarthritis pain. However, current interventions do not target either of these mechanisms. The Alexander Technique provides neuromuscular re-education and may also influence anticipation of pain. This study therefore sought to investigate the potential clinical effectiveness of the AT intervention in the management of knee osteoarthritis and also to identify a possible mechanism of action. METHODS: A cohort of 21 participants with confirmed knee osteoarthritis were given 20 lessons of instruction in the Alexander Technique. In addition to clinical outcomes EMG data, quantifying knee muscle co-contraction and EEG data, characterising brain activity during anticipation of pain, were collected. All data were compared between baseline and post-intervention time points with a further 15-month clinical follow up. In addition, biomechanical data were collected from a healthy control group and compared with the data from the osteoarthritis subjects. RESULTS: Following AT instruction the mean WOMAC pain score reduced by 56 % from 9.6 to 4.2 (P < 0.01) and this reduction was maintained at 15 month follow up. There was a clear decrease in medial co-contraction at the end of the intervention, towards the levels observed in the healthy control group, both during a pre-contact phase of gait (p < 0.05) and during early stance (p < 0.01). However, no changes in pain-anticipatory brain activity were observed. Interestingly, decreases in WOMAC pain were associated with reductions in medial co-contraction during the pre-contact phase of gait. CONCLUSIONS: This is the first study to investigate the potential effectiveness of an intervention aimed at increasing awareness of muscle behaviour in the clinical management of knee osteoarthritis. These data suggest a complex relationship between muscle contraction, joint loading and pain and support the idea that excessive muscle co-contraction may be a maladaptive response in this patient group. Furthermore, these data provide evidence that, if the activation of certain muscles can be reduced during gait, this may lead to positive long-term clinical outcomes. This finding challenges clinical management models of knee osteoarthritis which focus primarily on muscle strengthening. TRIAL REGISTRATION: ISRCTN74086288 , 4th January 2016, retrospectively registered.