# Clinical Cases: Lower Limb - Foot and Ankle

## Case 1: Weber B Ankle Fracture

### Clinical Image
![Ankle Fracture](case_01_image.jpg)
*Source: [Wikimedia Commons - Ankle Fracture](https://commons.wikimedia.org/wiki/File:Ankle_fracture.jpg) - CC BY-SA 3.0*

### Case Presentation
A 38-year-old woman presents to the emergency department after twisting her left ankle while walking down stairs in high heels. She reports immediate pain and swelling over the outer aspect of her ankle and was unable to bear weight. Physical examination reveals significant swelling and ecchymosis over the lateral malleolus. There is tenderness over the distal fibula at the level of the ankle joint. The medial side has mild tenderness but no bony tenderness over the medial malleolus. There is no tenderness over the proximal fibula (ruling out Maisonneuve injury). The squeeze test is negative. Neurovascular examination is intact. Radiographs demonstrate an oblique fracture of the distal fibula at the level of the tibial plafond (Weber B classification) with lateral shift of the talus and widening of the medial clear space to 6mm (normal <4mm), indicating deltoid ligament injury. The syndesmosis appears intact on radiographs. Given the unstable injury pattern with talar shift, she undergoes open reduction internal fixation of the fibula with a plate. Intraoperative stress testing confirms syndesmotic stability, and the deltoid ligament is not repaired. She is kept non-weight-bearing for 6 weeks with subsequent progression to full weight bearing.

### Key Learning Points
- The ankle mortise is formed by the tibial plafond, medial malleolus, and lateral malleolus
- Weber classification: A (below syndesmosis), B (at syndesmosis), C (above syndesmosis)
- Ankle stability depends on the bony ring and ligamentous support (syndesmosis, deltoid, lateral ligaments)
- Medial clear space widening >4mm indicates deltoid ligament injury and an unstable injury pattern
- Weber B fractures can be stable or unstable; instability requires operative fixation

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## Case 2: Achilles Tendon Rupture

### Clinical Image
![Achilles Rupture](case_02_image.jpg)
*Source: [Wikimedia Commons - Achilles Tendon Rupture](https://commons.wikimedia.org/wiki/File:Achilles_tendon_rupture.jpg) - CC BY-SA 3.0*

### Case Presentation
A 42-year-old man presents with acute left ankle pain after playing basketball. He was running and suddenly pushed off to sprint when he felt like he was "kicked in the back of the ankle." He heard a pop and immediately fell to the ground. He was unable to continue playing and has difficulty walking. He denies any prior Achilles problems but notes he had been taking ciprofloxacin for a urinary tract infection last week. Physical examination reveals swelling and ecchymosis over the posterior heel and distal leg. A palpable gap is present 4-6 cm proximal to the calcaneal insertion of the Achilles tendon. He has weakness of active plantarflexion but some movement is preserved (due to intact plantaris and toe flexors). Thompson test is positive - squeezing the calf while the patient is prone with feet hanging off the examination table does not produce passive plantarflexion of the foot. Simmonds squeeze test also positive. Ultrasound confirms complete Achilles tendon rupture at the watershed zone 4 cm proximal to insertion. After discussing options, he elects for operative repair given his active lifestyle. He undergoes primary surgical repair and is placed in a walking boot for 12 weeks with gradual rehabilitation.

### Key Learning Points
- The Achilles tendon is the strongest tendon in the body, formed by the gastrocnemius and soleus
- Rupture typically occurs 2-6 cm proximal to insertion (watershed zone of relative hypovascularity)
- Mechanism: forceful push-off, sudden dorsiflexion, or direct trauma; often in middle-aged "weekend warriors"
- Risk factors: fluoroquinolone antibiotics, corticosteroid injections, chronic tendinopathy
- Thompson test (calf squeeze test): no plantarflexion with calf squeeze indicates complete rupture

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## Case 3: Fifth Metatarsal Fractures

### Clinical Image
![Fifth Metatarsal Fractures](case_03_image.jpg)
*Source: [Wikimedia Commons - Jones Fracture](https://commons.wikimedia.org/wiki/File:Jones_fracture.jpg) - CC BY-SA 3.0*

### Case Presentation
A 25-year-old professional basketball player presents with lateral foot pain after landing awkwardly from a jump during practice. He reports immediate pain at the base of his fifth metatarsal and was unable to continue playing. He denies any prior foot injuries or pain at this location. Physical examination reveals point tenderness at the proximal fifth metatarsal, specifically in the metaphyseal-diaphyseal junction, rather than at the tuberosity. There is mild swelling over the lateral midfoot. He is unable to bear weight on the affected foot. Radiographs demonstrate a transverse fracture at the metaphyseal-diaphyseal junction of the fifth metatarsal, which is a true Jones fracture. There is no fracture of the tuberosity and no avulsion at the base. Given his athletic demands and the high nonunion rate of Jones fractures with conservative treatment, he undergoes intramedullary screw fixation. He is kept non-weight-bearing for 4 weeks, then progressed to weight bearing, and returns to full basketball activity at 10 weeks.

### Key Learning Points
- Fifth metatarsal fractures are classified by location: Zone 1 (tuberosity avulsion), Zone 2 (Jones fracture), Zone 3 (shaft stress fracture)
- Jones fracture occurs at the metaphyseal-diaphyseal junction, a watershed zone with poor blood supply
- Jones fractures have high nonunion rates (up to 30%) with conservative treatment due to limited vascularity
- Tuberosity avulsion fractures (Zone 1) result from peroneus brevis traction and heal well conservatively
- Athletes with Jones fractures often undergo operative fixation for faster return to sport and lower refracture rates