Teaching Case

The patient presented at the emergency department with acute and disabling pain localised in the left Achilles tendon. The patient's investigation revealed the presence of a previous trauma during sport activity. There was a palpable gap along the course of the tendon.

The patient, a 29-year-old man, presented with acute and disabling pain localised in the left ankle; there was a history of acute trauma during sports. The patient was not able to move his left foot. Examination revealed a palpable gap along the course of the Achilles tendon. In the emergency department an ultrasonography was performed and it showed a diffuse inhomogeneity within the tendon because of the presence of oedema and haemorrhage. US showed also the ends of the tendon as hyperechoic areas. Surgical reconstruction of the tendon was necessary: the two tendon stumps were sutured with both absorbable and non-absorbable wires. After 2 months the patient underwent a US as follow up; it showed thickening of the tendon and an area of effusion in the Kager's triangle. Signal of the tendon was inhomogeneous, as a sign of healing. Postoperative follow up included also a MRI examination: the MRI protocol included T2 and STIR sequences in axial and sagittal planes. T2 and STIR sequences showed diffuse thickening of the tendon, which was hyperintense at the site of rupture but having a normal signal at the insertion on the calcaneum. Furthermore they showed tenosynovitis of the posterior tibial tendon because of postural imbalance.

Achilles tendon ruptures are increasing in frequency due to an increase in athletic activity, especially in 30-40 years old men. Although most Achilles tendon ruptures occur during sporting activities, intrinsic structural, biochemical and biomechanical changes related to aging may play a significant role.
Achilles tendon rupture is more common in males with a male-to-female ratio of 15:1. Typically, an acute rupture of the Achilles tendon occurs in males who play sports occasionally.
The aetiology of Achilles tendon rupture still remains unclear. Probably the association of degenerative changes (related to alterations in blood flow and impaired metabolism) and sports (which place additional stress on the tendon) can lead to complete rupture, as a consequence of multiple microruptures. Also prolonged administration of corticosteroids and fluoroquinolones have been related to Achilles tendon rupture.
In most cases the acute rupture occurs during weightbearing, with the forefoot pushing off with the knee in extension.
Diagnosis of acute Achilles tendon rupture can usually be made by history and physical examination alone. MRI or ultrasound can be helpful in cases of suspected rupture for pre-operative planning. Patients with ruptured Achilles tendon typically have an history of sudden pain in the affected leg. They are often unable to bear weight and notice weakness or stiffness of the affected ankle.
Examination may reveal diffuse oedema and bruising and a palpable gap may be felt along the course of the tendon. The site of rupture is usually 2 to 6 cm proximal to the insertion of the tendon.
Ultrasonography of the Achilles tendon is a primary imaging method; a normal Achilles tendon appears as a hypoechoic image contained within 2 hyperechoic bands. Acute rupture of the Achilles tendon is seen as an acoustic vacuum with irregular edges and it is characterised by an enlarged tendon with discontinuity of the normal pattern of parallel fibres at the site of rupture. Furthermore, a haematoma forms at the site of rupture.
On MRI the normal Achilles tendon is seen as an area of low signal intensity on all sequences. Any increase in intratendinous signal intensity should be regarded as abnormal. In T2 weighted images the rupture is demonstrated as a generalised increase in signal intensity because of the presence of oedema and haemorrhage.
The management of an acutely ruptured Achilles tendon depends on the preference of surgeon and patient. The most common nonoperative management consists in immobilisation using a plaster cast, usually for a period of 6 to 10 weeks. Although function following nonoperative repair is generally good, there is high incidence of rerupture (15%).
In the open operative management a longitudinal incision is made next to the medial border of the tendon on the palpable gap. After juxtaposing the ends, the tendon is sewn together with strong absorbable suture. The leg is then immobilised in a plaster cast, which is removed after 2 weeks.