The aim of this bicentric, biphasic, randomized, controlled study is to compare of the current gold standard functional treatment to functional treatment plus WBV in patients with acute unilateral unstable inversion ankle sprains over a period of 12 months

Background:

Ankle sprains often result in ankle instability, which is most likely caused by damage to passive and neurological structures. Whole body vibration (WBV) is a neuromuscular training method improving those neurologic parameters impaired. The aim of this study is to compare the current gold standard functional treatment to functional treatment plus WBV in patients with acute unilateral unstable inversion ankle sprains.

Methods/Design:

60 patients, aged 18-40 years, presenting with an isolated, unilateral, acute unstable inversion ankle sprain will be included in this bicentric, biphasic, randomized controlled trial. Patients will be randomized by envelope drawing. All patients will be allowed early mobilization and pain-depending weight bearing, limited functional immobilization by orthesis, PRICE, NSARDs as well as home and supervised physiotherapy. Supervised physical therapy will take place twice a week, 30 minutes per session, for 6 weeks, following a standardized intervention protocol. During supervised physical therapy, the intervention group will perform similar exercises on a side-alternating sinusoidal vibration platform as the control group. Two time dependent primary outcome parameters will be assessed. Short-term outcome after six weeks will be postural control quantified by the sway index. Mid-term outcome after one year will be assessed by subjective instability, defined by the presence of giving-way attacks. Secondary outcome parameters include return to pre-injury level of activities, residual pain, recurrence, objective instability, energy / coordination, Foot and Ankle Disability Index and EQ 5D.

Inclusion Criteria:

• Acute, unilateral, unstable, inversion ankle sprain (Grade II, III)

Exclusion Criteria:

• Pregnancy
• Conditions affecting the neuromuscular- or musculoskeletal System
• Previous surgical interventions to the foot, ankle, knee or hip; known FAI, CAI
• Conditions possibly affecting balance
• Cardiovascular disease including thrombosis
• Respiratory diseases
• Abdominal diseases (including gallstones)
• Urological diseases (including kidney- and bladder stones)
• Gynaecological diseases and + intrauterine devices
• Neurological diseases including epilepsia within the last 2 years
• Acute injuries to the head
• Patient is not available for follow up visits
• Patient unable to give informed consent
• Patient suspected to be non-compliant