🦶 Ankle Pain

The Ottawa Ankle Rules (OAR) were developed at the University of Ottawa in 1992 and are highly sensitive for ankle and midfoot fractures when correctly applied, with limited specificity, and reduce unnecessary X-rays. NICE NG38 recommends them for people over 5 years; they are less reliable with altered mental status, intoxication, distracting or multiple injuries, neuropathy, an unreliable examination, or suspected stress or pathological fracture. Critically, inability to take four weight-bearing steps both immediately after the injury and at assessment is as important a criterion as bony tenderness. Achilles tendon rupture is a commonly missed significant ankle injury — the Simmonds–Thompson test takes seconds and should be performed in every case of acute Achilles/posterior heel pain or sudden loss of push-off. A palpable gap may be absent, especially with swelling or delayed presentation.

The distinction between an acute lateral ligament sprain and a chronic ankle instability syndrome is clinically important. A single significant sprain that is inadequately rehabilitated leads to persistent proprioceptive deficit and mechanical laxity — the patient describes the ankle "giving way" on uneven ground. This is not a new injury each time but ongoing instability from the original inadequately healed ligament. The treatment is proprioceptive rehabilitation via physiotherapy, not repeated rest and RICE. Patients who present with recurrent "ankle sprains" without adequate rehabilitation should be referred to physiotherapy for a structured proprioceptive and strengthening programme. Persistent instability despite structured physiotherapy may indicate a ligament reconstruction referral to orthopaedics.

Peroneal tendon pathology is a commonly missed diagnosis after an ankle sprain — some patients with "chronic lateral ankle pain after sprain" have a peroneal tendon tear rather than residual ligament injury. The peroneal tendons run posterior to the lateral malleolus in a shared fibrous tunnel — they stabilise the ankle in eversion and are stressed during inversion injuries. A peroneal tendon tear presents with persistent lateral ankle pain, swelling along the peroneal tendons (not at the ligament), and pain with resisted eversion. If lateral ankle pain persists beyond 6–8 weeks without improvement despite appropriate management, consider USS or MRI of the peroneal tendons, or refer to physiotherapy/MSK, where the diagnosis is uncertain or surgery is being considered. Fluoroquinolone antibiotics (ciprofloxacin, ofloxacin) are a significant risk factor for tendon rupture — both Achilles and peroneal tendons — via an unclear mechanism. MHRA Drug Safety Updates (March 2019; January 2024 — use only when other commonly recommended antibiotics are inappropriate) restrict fluoroquinolone use because of disabling, long-lasting effects including tendinopathy and tendon rupture, and the SPCs carry the warning (the US FDA boxed warning is the international equivalent). Avoid inappropriate prescribing, particularly with current tendinopathy; the MHRA advises stopping a fluoroquinolone at the first sign of tendon pain or inflammation, avoiding concurrent corticosteroids where possible, and recognising that tendon damage can occur during treatment or several months afterwards.

Serum urate during an acute gout attack may be paradoxically normal or low — the acute inflammatory response redistributes urate from serum into the joint and tissues. A normal urate during an acute attack does not exclude gout. If urate is normal during a flare, NICE NG219 (2022) advises repeating it at least 2 weeks after the flare has settled to establish the true level. The treat-to-target urate for ULT is <360 μmol/L, with a lower target of <300 μmol/L considered for tophi, chronic gouty arthritis or continuing flares (NICE NG219). The mortise view (15–20° internal rotation) is the most important X-ray for ankle assessment — it shows the tibiotalar joint space and the integrity of the ankle mortise. A widened lateral clear space (>5 mm) indicates syndesmotic disruption — a high ankle sprain that requires orthopaedic assessment and may need screw fixation.

The management of acute Achilles tendon rupture (conservative vs surgical) remains debated — the UKSTAR trial (Costa et al., Lancet 2020) showed that, for non-surgically treated ruptures, immediate weight-bearing in a functional brace (walking boot) was as good as a plaster cast, with better early patient-reported outcomes; non-operative treatment also avoids surgical complications such as wound infection and sural nerve injury, at the cost of a slightly higher re-rupture rate. Most UK orthopaedic centres now offer functional conservative management (immediate weight-bearing in equinus CAM boot) as the primary approach, reserving surgery for young athletes with high performance demands. The GP's role is to diagnose the rupture, arrange temporary immobilisation in plantar flexion (avoid dorsiflexion) or immediate orthopaedic referral, and arrange same-day review — not to decide on surgical vs conservative management.

The Alfredson eccentric loading protocol for Achilles tendinopathy was developed in 1998 and is one of several evidence-based loading programmes — isometric and heavy slow resistance programmes are alternatives. Eccentric (lengthening) contractions specifically stimulate neovascularisation and collagen remodelling in the tendon. The programme requires compliance with twice daily exercises for 12 weeks — explaining the mechanism and time commitment to patients significantly improves adherence. Corticosteroid injection into or around the Achilles tendon should be avoided because of rupture risk. This is in contrast to plantar fasciitis (where steroid injection may be considered selectively after an adequate conservative programme). Starting allopurinol during an acute gout attack can prolong the attack — NICE NG219 (2022) advises starting ULT 2–4 weeks after the flare has settled (it can be started during a flare if flares are frequent), with prophylactic colchicine or NSAID cover for the first 3–6 months.

VTE prophylaxis in lower limb immobilisation is a frequently neglected clinical duty in primary care. NICE NG89 (VTE prevention) advises that people whose lower-limb immobilisation prevents normal weight-bearing or use of the limb should have a VTE and bleeding risk assessment; it does not recommend automatic prophylaxis for every ankle injury, boot or plaster. NG89 advises considering LMWH or fondaparinux only when the VTE risk outweighs the bleeding risk, with review if immobilisation continues beyond 42 days. Whoever arranges immobilisation should document the VTE risk assessment. Prophylactic LMWH doses are fixed, not the weight-based treatment doses — dose per NICE/SPC (for example enoxaparin 40 mg OD subcutaneously).

Proprioceptive rehabilitation is the most important component of ankle sprain management for preventing recurrence — yet it is rarely prescribed in primary care, where PRICE (Protection, Rest, Ice, Compression, Elevation) is often the only advice given. Recurrence is common without proprioceptive rehabilitation and is reduced by a structured balance training programme. The mechanism is restoration of ankle proprioceptive afferent signalling — ligament injury disrupts the mechanoreceptors in the ligament, impairing balance and increasing the risk of re-injury. Balance board training retrains the central nervous system to compensate. This takes 12 weeks of consistent daily practice. Gout medication review is often the most impactful intervention — thiazide diuretics (bendroflumethiazide, hydrochlorothiazide) significantly raise serum urate and are a major treatable contributor to recurrent gout. Switching to an alternative antihypertensive (amlodipine, losartan — the latter is mildly uricosuric) can reduce gout frequency dramatically without ULT.

Extracorporeal shockwave therapy (ESWT) for chronic refractory Achilles tendinopathy delivers acoustic shockwaves through the skin to stimulate neovascularisation and collagen remodelling in the tendon, usually as an outpatient course once conservative treatment (including eccentric loading) has failed. NICE HTG426 (formerly IPG571, 2016) found no major safety concerns but inconsistent, limited efficacy evidence, so it should only be used with special arrangements for clinical governance, consent and audit or research. It is not available in all areas but can be accessed via physiotherapy MSK services or private. PRP (platelet-rich plasma) injection for tendinopathy has inadequate or uncertain efficacy evidence (NICE HTG299: special arrangements only) and is not routinely available on the NHS. The key principle: if around 12 weeks of a compliant loading programme fails, referral to a specialist MSK service is warranted rather than simply continuing the same management.