Traumatic Injury to the Facial Nerve or its Branches: This is the most likely diagnosis given the history of a hard nose blow leading to a ruptured ball in the nose. The facial nerve has branches that supply the face, and trauma to these areas can cause numbness.

Nasal Septal Hematoma: A hard blow to the nose can cause a collection of blood in the nasal septum, which may compress or damage nearby nerves, leading to numbness.
Fracture of the Nasal Bones or Sinuses: Such fractures can cause nerve damage or compression, resulting in facial numbness.
Soft Tissue Injury: Significant soft tissue injury around the nose and face can also lead to nerve damage.

Cavernous Sinus Thrombosis: Although rare, this condition can occur after a facial injury, especially if there's an infection. It's a serious condition that requires immediate medical attention.
Meningitis or Encephalitis: In rare cases, a severe head or facial injury can lead to infections like meningitis or encephalitis, which are life-threatening.
Carotid Artery Dissection or Stroke: A hard blow to the neck or head can potentially dissection the carotid artery or cause a stroke, both of which are medical emergencies.

Multiple Sclerosis: While rare in this context, multiple sclerosis can cause facial numbness. However, it would typically be accompanied by other neurological symptoms.
Lyme Disease: Neurological manifestations of Lyme disease can include facial numbness, but this would be part of a broader clinical picture including other symptoms like fever, rash, and joint pain.
Sarcoidosis: This autoimmune disease can affect the nerves and cause facial numbness, but it's a rare condition and would likely present with other systemic symptoms.