Ankle
Ankle sprains are one of the most common sporting injuries requiring
treatment. The mechanism is usually inversion damaging the anterior talofibular
(ATF) and subsequently the calcaneofibular (CF) ligaments (Fig.
29.8). Surgery
to repair the ligaments is rarely required; functional bracing with early
weight-bearing allows the ligaments to heal whilst maintaining ankle motion.
If
the recovery after ankle sprain is slow then chondral damage to the talar dome
should be suspected. Bone scintigraphy is the most sensitive investigation and
lesions can be treated with arthroscopic débridement.
Recurrent
lateral instability of the ankle requires a rehabilitation programme
concentrating on restoration of proprioception but if this fails then repair
is indicated. A direct repair of the ligament ends is usually possible,
otherwise the use of a periosteal flap from the fibula or a free hamstring
autograft may be used to reconstruct both the ATF and the CF ligaments. The
use of some or all of the peroneal tendons for reconstruction is best avoided as
they are the dynamic stabilisers to inversion.
Posterior
impingement of the ankle is practically an occupational hazard in ballet
dancers. With the ankle in point (forced plantar flexion) the posterior
malleolus, the talus and the calcaneum compress the soft tissues causing
inflammation. An os trigonum may or may not be present, but the diagnosis is
made by reproducing the pain of impingement. With the patient prone, plantarflex
the ankle and compress the heel whilst moving the forefoot from side to side.
Treatment is surgical resection of the soft tissue, or os trigonum if present,
via a short medial approach.
Repeated
trauma to the anterior joint capsule causes anterior osteophytes
(‘footballer’s ankle’) which limit dorsiflexion. These may be resected
via the arthroscope.
Forced
eversion of the ankle may disrupt the sheath surrounding the peroneal tendons
allowing them to subluxed anteriorly. The athlete reports a ‘snapping’
sensation with activity and resisted eversion demonstrates the abnormality.
Splints are ineffective at keeping the tendons in place so surgery is required
to repair the defect in the sheath, supplementing it with a periosteal flap.
Ruptured
tendoachilles
Rupture of the tendo achilles (TA) most commonly occurs in patients in
their 40s who experience a sharp snap while running or jumping. Over 80 per
cent occur during sport, and the athlete describes a feeling of being struck in
the back of the heel. On examination there is tenderness and swelling over the
TA and careful palpation may reveal a dent in the TA, especially if it is
compared with the other side. Paradoxically the patient may still be able to
stand using their long toe flexors, although it may be painful. Simmons’ test
involves lying the patient face down on the couch with their feet hanging over
the edge of the bed. If the calves are
Management
If the tear is at the musculotendon junction high up in the calf then
treatment only needs to be symptomatic, but if it is in the middle of the
substance of the tendon then the two ends must be brought into close apposition
for healing to occur. This can be done by managing the patient in a below-knee
plaster with the ankle in full equinus. Serial plasters are may be used to bring
the foot up into neutral. After a total of 6—8 weeks the leg is taken out of
plaster and mobilisation of the ankle is started. Surgery to appose the tendon
ends may be performed through a longitudinal medial incision (open) or via stab
wounds (percutaneous) (Fig. 29.9). Accelerated rehabilitation regimes with
functional braces are now commonly used. Ankle mobilisation starting 7 days
after repair and 3-4 weeks after nonsurgical treatment lowers the re-rupture
rate and maintains better muscle function.
Nonsurgical
treatment has a re-rupture rate of 6—10 per cent, open repair risks wound
breakdown (1—2 per cent) which is a disaster, and percutaneous repair may lead
to sural nerve injury. The results of the few prospective randomised trials have
unfortunately been inconclusive, so surgeons should stick to what works best for
them.