Literature concerning ankle injuries is abundant, probably due to the high incidence in both the recreational and competitive athletes (Gross et al, 1987). The most common ankle injury is a lateral sprain or inversion injury with more than 25 000 occurring each day in the U.S (Pfeffer et al, 1997). Closer to home, Bridgeman et al (2003) found during a United Kingdom (UK) based epidemiology study that the incidence of ankle sprain related attendances to Accident and Emergency (A&E) accounted for 52.7 per 10 000 patients. Moreover, 14% of ankle sprains seen in A&E were classified as severe equating to 42 000 severe ankle sprains per year in the U.K. A large proportion of this number would be expected to filter into the musculoskeletal outpatient setting, however Hertal (2002) proposed that 55% of patients do not seek further medical advise and are in danger of developing a chronically unstable ankle.

Anatomy and Biomechanics

The lateral side of the ankle joint has an inherent vulnerability to ligamentous sprain due to its anatomical and biomechanical makeup. Together the talocrural and subtalor joints allow inversion and eversion (Hertel et al, 1999). The medial malleolus is proportionally shorter than the lateral, which in turn creates a fulcrum that can predispose the ankle to inversion sprains (Booher & Thibodeau, 1994). There are three main lateral ligaments of the ankle, the anterior talofibular ligament, posterior talofibula ligament, and the calcaneofibular ligament. When the lateral ligament complex is overstretched beyond its normal mechanical means, partially torn or ruptured, the inflammatory response will be initiated (6-24 hours) with the ensuing initiation of the proliferation and maturation stages of healing (Mattacola & Dwyer 2002, Obrascous 1985). Routine physiotherapy must be initiated as soon as possible following a sprain in order to maximize the inflammatory process, initiate collagen stretching and strengthening exercises (Mattacola & Dwyer, 2002) and finally begin an appropriate proprioception exercise circuit (Murphy et al, 2003). Poor or prolonged initiation of correct rehabilitation following injury is one cause of chronic ankle instability (CAI).

Chronic ankle instability can be defined as the inability to control normal motion of the ankle leading to recurrent sprains or giving way (Morrison et al, 2007). Morrison et al (2007) studied anatomical foot and ankle characteristics associated with CAI during a systematic review and identified several mechanical predisposing factors to CAI: Greater foot width, a high longitudinal arch, greater metatarsalphalangeal joint extension, cavovarus foot deformity, subtalor joint instability and weight bearing on the lateral side of the foot during gait were all seen as risk factors. Hypermobility syndrome is a congenital disorder of the connective tissue and is associated with CAI (Bird, 2007). CAI may manifest itself with pain in conditions such as Marfans syndrome, osteogenisis imperfecta and Ehlers-Danlos (Hakim & Graham, 2003). It is also accepted that poor neuro-muscular control, proprioception, inexperience (learning) and postural control have a large part to play in CAI (Ross et al, 2002. Robbins et al, 1995. McKnight & Armstrong, 1997).

Margarita and Reyes (2010) considered ankle taping important in both the acute and chronic stages of healing. In the acute stages ankle taping is used to control swelling and range of movement (Callaghan 1997) which fulfills the protection, rest and to a lesser extent compression components of the National Institute of Clinical Excellence (N.I.C.E) recommendations for acute ligamentous sprains (P.R.I.C.E). Capasso et al (1989) compared non-adhesive and adhesive tape on ankle oedema. The authors found that non-adhesive tape should be replaced after three days owing to insufficient compression, however the adhesive tape could last for five days. Compressive forces were measured during this study by combining a sphygmomanometer in with the ankle taping. The method of data collection can however been criticised as it does not provide an exact measurement. The participants were asked to heel strike, full foot weight bear and toe off weight bear in a mechanical action where between phases a reading was taken whilst the position was held. This cannot offer a functional representation to gait and does not reflect a real time gait cycle. Moreover, three ‘operators’ were used to tape the ankles and although they followed a standardised method, there was no mention about how pressure applied was normalised.

In a much more sophisticated study, Boyce et al (2005) compared the value of taping and bracing in acute ankle sprains. The authors randomised 50 participants into two even groups: one was treated with an Aircast™ ankle brace and the other with a supportive elastic tape. Participants were reviewed at 10 days and 1 month post intervention. Ankle joint function was measured using the Karlson score whilst ankle girth measured swelling, both groups showed significant improvements (p=0.028 and p=0.014 respectively) in the bracing group compared with taping. Six out of seventeen participants in the taping group did not complete this study thus demonstrating a somewhat poor compliance to ankle taping. Callaghan (1997) supported this observation in their literature review comparing ankle taping and bracing in the athlete and felt taping may be of an inconvenience to the participant and may be less comfortable than a brace.

Both Boyce et al (2005) and Capasso et al (1989) used several different examiners to tape and collect data, this has a detrimental impact on the reliability of data, using just one examiner would eliminate this bias and improve the reliability of the studies. Furthermore, neither Boyce et al (2005) nor Capasso et al (1989) used a control group, consequently it would be hard to extrapolate the proposed benefits of the tape and bracing when improvements due to the normal healing process have not been controlled for.

The use of ankle taping as a mechanical stabiliser

The act of taping an ankle to provide an external support has been evidenced in the literature dating back to the 1880’s when it was used by the U.S. Army (Libera, 1967). A hypermobile ankle joint is often seen as the predisposing mechanism of injury for a lateral ligament sprain. Therefore, it is logical to assume that by mechanically limiting this excess in movement one might reduce the incidence of ankle sprain (Reisburg & Verstraete, 1992).

Historically, passive range of movement (ROM) has been the most frequently utilised objective measure when studying ankle-taping effectiveness. Lohrer et al (1999) used electromyography and goniometry methods to examine talor tilt and neuromuscular adaptation in 40 subjects. The mechanical displacements of the joint complex were analysed before and after controlled athletic exercise. Inversion was reduced my a mean of 50% using the ‘basket weave’ method of taping and a post exercise restriction decrease of 66% (lower values represent greater restriction). Both fatigue and mechanical loosening were deemed responsible for the restrictions in mechanical stability. Fatigue was not controlled for in this study nor were the participants blinded to the aims – thus creating a participant bias. The authors could have provided a likert scale questionnaire in the form of a subjective level of tiredness, which would have quantified fatigue. In a similar study, (using roentgenologic measurements of talor tilt) Vaes et al (1998) found a medial subtalor sling (taping method) decreased mean inversion by 37%-78% pre exercise and 52%-88% post exercise. It must be stressed that in both these studies, testing was performed passively to the limits of restriction, and although these restrictions would maintain talor tilt within normal ranges (uninjured ranges), restriction may not be adequate to prevent sprain. Studies using non-weight bearing methods of measuring talor tilt do quantify passive restriction qualities of tape nicely, however they cannot be seen as functional. The stress through the ankle joint complex is much higher during an actual inversion injury, loading the joint at pressures typical for sprains may consequently yield different results.

The ‘trap-door’ method of measuring joint restriction with taping is said to mimic the mechanism of injury; as a result, movement limitations can be assessed during a more realistic activity. The disadvantage to this method however has been the limitation of assessed ranges coupled with the fact that it is a static measure.

Ricard et al (2000) randomly assigned 30 physically active college students who had a history of ankle sprains. The authors excluded participants who had sprained within the last 4 weeks, had a painful gait, or previous ankle surgery. Data was collected using an electronic goniometer while