Mitchell, a 43-year-old labourer, presents with 48 hours of worsening ache in the left lower back, hip and posterior thigh, as well as left leg weakness.

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<p>Mitchell, a 43-year-old labourer, presents with 48 hours of worsening ache in the left lower back, hip and posterior thigh, as well as left leg weakness.</p><p>Mitchell is typically very well. He has a remote past history of DVT and, more recently, appropriately self-managed mechanical back pain.</p><p>Mitchell has made several long-haul car trips for contract work in recent weeks. Four days ago, he was diagnosed with a recurrent right lower leg DVT and restarted rivaroxaban.</p><p>Prolonged driving often provokes his back pain. However, this episode differs in location and intensity and is worsening despite usual management.</p><p>His right leg swelling is subsiding. The left hip is irritable, with marked pain and weakness with hip extension.</p><p>A lumbosacral CT scan is requested (pictured, L5 level).</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.