The Achilles tendon is the largest tendon in the body. Tendinopathy and rupture can affect both athletes and those with sedentary lifestyles
Acute injury (i.e. rupture) to the Achilles tendon usually occurs from sudden acceleration or deceleration. This is different to Achilles tendinopathy – which is often a chronic overuse condition
Achilles tendon rupture occurs in athletes in 80% of cases. It is more common in those who have had previous Achilles tendon problems
Achilles tendon rupture can be partial or complete
Complete tears are usually managed surgically, but in older sedentary patients may be managed conservatively. Surgical management reduces the risk of re-rupture, but has a higher acute complication rate
Aetiology
Usually in athletes
Most commonly in sports that involve a quick acceleration – e.g. sprinting, tennis, basketball, football
Typically aged 30-50
M > F
May also occurs as a result of a fall with forces dorsiflexion
The Achilles tendon connects the gastrocnemius and soles muscles to the posterior of the calcaneus
It begins at the mid calf
It has slightly unusual anatomy – there is not true synovial sheath and instead it is surrounded by a sheath called the paratenon.This is a highly vascular structure and it allows for a sliding action of the tendon inside the paratenon
The blood supply is least around the mid tendon – defined as the region 2-6cm proximal to the insertion. This is the area most likely to rupture
Presentation
Sudden onset Achilles tendon pain. Initially sharp pain, often settles within hours to days to more of a dull ache
A loud “snap” or “bang” is sometimes heard when the tendon ruptures!
Some patients report feeling as though they were hit on the back of the tendon
Usually occurs with a pushing-off motion – in contact to ankle sprain, which is often due to impact on landing
Inability to stand on tip toe on affected side
Examination
Often localised swelling
Altered gait
Inability to stand on tip toes
Reduced plantar flexion
Simmond’s Triad. Ask the patient to lay prone on the couch, with their feet dangling off the end of the bed. Compare both sides. Check:
Altered “angle of dangle” – in Achilles tendon rupture the affect foot will naturally “dangle” in a more dorsiflexed position than the unaffected side
Calf squeeze (aka Thomson’s calf squeeze test) – in a normal, intact Achilles tendon, a calf squeeze should cause plantar flexion of the ankle. In Achilles tendon rupture, there will be minimal or no plantar flexion
Palpable notch or gap in the Achilles tendon at this site of the rupture
Investigation
Often a clinical diagnosis
USS (usually first line) or MRI can help to differentiate a partial from a complete tear, or to narrow down differentials
Achilles tendon rupture on USS. The area of disrupted tissue is indicated by the red line. Image by Hellerhoff is licensed with CC BY-SA 3.0
Management
Non-weight bearing – immediately
Urgent referral to orthopaedics – surgery is usually required
Surgical repairs reduces the risk of subsequent recurrent rupture, but also carries risks – such as wound infection
Following surgery, rehabilitation plan is often similar to conservative management outlined below
80% of athletes return to sport
Athletes may not be able to resume full activity for up to 1 year
There is often some loss of function – even small amount of functional loss can have a significant impact for athletes
Conservative management is an option for older more sedentary patients – but decision should be made by orthopaedic specialist
Plaster cast for 2 weeks
Can be changed to immobilising boot from 2 weeks
Weight bear as pain allows from 4-6 weeks
Physiotherapy involvement from the start
Partial tears are usually managed conservatively, with an immobilisation boot from the start, and earlier weight bearing
Complications
Achilles tendon scarring and contracture – especially if there is not early mobilising and range of movement exercises – best direct by physiotherapist
