Prepare the dressing first. In a small bowl, whisk together the ketchup, mustard, Worcestershire sauce, horseradish, vinegar, mayonnaise and vegetable oil.
Continue whisking until the mixture is smooth and creamy. Stir in the onion and garlic. Season to taste with black pepper and divide the dressing between 4 small bowls for serving.
Place the crabmeat in a bowl and check thoroughly for any bits of shell that might remain. Add the lemon juice and a few grinds of black pepper. Toss to combine and set aside.
Remove 16 of the outermost leaves from the romaine, wash and pat dry. Arrange four of these leaves in a spoke pattern on each of four plates. Wash and dry the remaining lettuce, chop roughly and mound it in the center of each plate. Top with crabmeat and sprinkle with chives.
Arrange the egg slices, tomato wedges, cucumber and asparagus spears around the edges of the plate. Serve with dressing and a lemon wedge.