Orthopaedics

Wear in the foot, knee or hip joints can have various causes: long-term overload from excess weight or work, malalignment, post-traumatic, genetic or metabolic causes. In all cases there is increased cartilage abrasion in the joint surfaces and remodelling of the subchondral bone.

As long as there are no large-scale cartilage defects yet, stochastic resonance therapy can intervene positively: by improving subchondral circulation and treating accompanying osteoporosis. Under these conditions better regeneration of cartilage tissue is possible.

Here stochastic resonance therapy works by increasing voluntary muscular activation potential, triggered by the release of neurotrophic substances. Combining it with heat therapy is conceivable to aid regeneration of irritated receptor systems.

Stimulating the receptor systems triggers reflex activation; neural cell assemblies are trained independently of voluntary motor control. The unpredictability of the movements also generates high cerebellar activity, improving movement confidence and the timing of movement sequences.

The therapy is used for hip, femoral neck, lower leg and foot fractures as well as knee joint and patellar fractures, among others.

The effect arises from activating osteoblast activity; the stochastic stimuli additionally optimise preflex-reflex control of muscle activity. Practical observations describe a more favourable course; tendons, supporting tissue and postural muscles are strengthened — which can reduce strain on adjacent joints.

With longer-term use it can also support bone metabolism and gait stability in older people.

Here the therapy pursues three goals: improving movement function by mobilising the capsule-ligament apparatus, “running-in mechanisms” at the edge of the resected meniscus cartilage, and strengthening and regenerating the mostly traumatically altered joint cartilage around the lesion.

Stochastic resonance therapy intensifies metabolic processes in bone and cartilage and prevents the local metabolic problems with subchondral decalcification typically expected after surgery. It is performed for four weeks, two to three times per week; from the second week the first cycles can be done standing crosswise on the plates.

Treatment can begin just a few days after surgery — naturally at the lowest intensity and with the knee flexed (more than 10–15°). Depending on the location of the rupture, positioning is varied so the therapy remains pain-free; intensity can then be increased. Overall, healing time is shortened significantly.

Hip replacements are implanted for painful coxarthrosis and for traumatic, osteoporotic or tumour-related fractures; knee replacements for osteoarthritis, fractures or tumours. Stochastic resonance therapy is used with both cemented and cementless implants.

The effect arises from activating osteoblast activity (bone formation) and reducing any concurrent osteoporosis: the bond with the foreign material — implant or cement — is accelerated and strengthened, ingrowth is faster and fixation better.

With cemented implants, therapy can start about 14 days after surgery — at very low intensity with slow progression over six weeks, then once weekly for a further six weeks. With cementless implants, therapy usually starts five to six weeks after surgery, again gently and with slow progression to medium intensity.

Stochastic resonance therapy is an essential part of the overall therapy determined by the treating physician, which also addresses common accompanying conditions such as inactivity-related trunk muscle atrophy.

It works by stimulating osteoblast activity. At the same time the trunk musculature is strengthened — improving spinal support and slowing further degenerative processes. A positive effect shows in the improved muscular situation; higher bone density can naturally only be measured after roughly 6 to 12 months.

The particular effect arises from strengthening tendon tissue by activating fibroblast activity and from mobilising the tissue adhesions inevitably caused by surgery in the tendon and joint capsule area. This can support the rehabilitation of mobility and load capacity.

Load stability is expected around six weeks after surgery. Since the ligaments are not under significant tension in normal standing, therapy can start three weeks post-op — two to three times a week at low intensity. The affected side can initially be partially loaded; from week seven the first and second cycles can be done standing crosswise on the plates.