OARSI 2013 - Presentation Info

S. J. Preece1 R. K. Jones1 C. Brown2 A. Jones2 T. Cacciatore3;
1Univ. of Salford Manchester UNITED KINGDOM 2Univ. of Manchester Manchester UNITED KINGDOM 3Univ. Coll. London London UNITED KINGDOM.

Purpose:
Previous research has consistently demonstrated elevated levels muscle of co-contraction in patients with knee OA. The level of co-contraction is typically highest between the medial hamstrings and medial quadriceps and occurs during the early stance phase of walking. It has been suggested that patients with knee OA increase muscle activity in order to maintain knee joint stability. However given that increased co-contraction will increase loading across the knee joint it could equally be a maladaptive response which acts to maintain the patient in a state of chronic pain. If this is the case then we would expect decreases in co-contraction to be accompanied by reductions in clinical pain.
The Alexander Technique (AT) is a method of movement re-education which aims to alter patterns of muscle tension. A recent large scale trial demonstrated that the AT can provide symptom relief for patients with chronic low back pain and another study found the AT was able to reduce spinal stiffness. This led the authors to suggest that AT may be effective because it rebalances ongoing muscle activity (muscle tone). Given the focus of the AT on patterns of muscle tension it may be an effective method for reducing increased co-contraction in patients with knee OA.
We investigated whether the Alexander Technique would be effective at reducing co-contraction and pain in patients suffering with knee OA. In addition we investigated whether any decreases in co-contraction would be accompanied by decreases in pain.
Methods:
A total of n=11 patients (5 male) suffering with knee OA were recruited from primary care. Each patient underwent a baseline biomechanical gait assessment after which they were given 20 lessons of instruction in the AT. Each patient was then reassessed after the intervention. At each of the two assessment points EMG data were collected and used to quantify the level of co-contraction during walking between the quadriceps and hamstrings. In addition kinematic and kinetic data were collected for the lower extremity segments. Clinical pain/disability was assessed using the WOMAC instrument and individual pain scores were obtained by summing the items from the WOMAC questionnaire which focus specifically on pain.
Results:
Following instruction in the AT there was a significant (p<0.01) reduction of 15% in medial co-contraction. However no changes were observed in lateral co-contraction or in any kinematic/kinetic variables. In addition there was a 56% decrease (p<0.01) from 45 to 20 in the WOMAC score and a decrease of 60% (p<0.01) in the WOMAC pain score. The analysis revealed a relatively strong correlation of r=-0.67 (p<0.05) between the change in medial co-contraction and the change in the WOMAC pain score.
Conclusions:
The finding of a strong correlation suggests that the AT was effective at reducing pain/disability because it reduced muscular co-contraction. Although these finding suggest that elevated co-contraction may be a maladaptive response further work is needed to understand whether reducing co-contraction in patients with knee OA compromises knee joint stability. Although future large-scale studies are required our results demonstrate the potential for interventions such as the AT which focus on reducing levels of muscle activity during functional activity.