Place a medium pot over medium heat with the chicken stock. Bring up to a simmer and reserve warm. Place a medium pot of water over high heat to boil.
Place a large skillet over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the sausage to the pan and brown, breaking it up with a wooden spoon as it cooks, 6-8 minutes.
When the sausage is almost ready, drop the broccoli rabe into the boiling water and cook until tender, about 1 minute. Scoop the broccoli rabe out of the water with a spider or slotted spoon and add it to the pan with the sausage. Add half of the garlic, nutmeg, salt and pepper, and cook for about 1 minute. Reserve warm until the risotto is ready.
While the sausage is browning, place a high-sided skillet over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the onion and remaining garlic to the pan and cook until tender, 4-5 minutes. Add the rice to the pan and cook until lightly toasted, about 1 minute. Add the wine and cook until most of it has evaporated. Add a ladle of the reserved warm stock to the pan and cook, stirring frequently, until it has absorbed. Continue adding stock, one ladleful at a time, while stirring frequently until the rice is tender and creamy, about 18 minutes. Stir in the butter, grated cheese and season with salt and pepper.
To serve, spoon a bed of risotto into the bottom of a shallow bowl and top with a scoop of the sausage and broccoli rabe.