Blount's disease

The Blount 's disease, also Blount 's disease or Erlacher - Blount 's disease is the infantile form of tibia vara ( in humans), a deformation of the lower leg bone as a result of a growth disorder of the medial growth plate. The disease was named after the discoverer and describer Walter Putnam Blount ( 1900-1992 ). The disease is rare, but more common among the population of African origin in South Africa.

Two forms can be distinguished:

• Occurring on both sides Infantile form in children under 10 years, mostly in the first years of life, usually
• Adolescents, juvenile or late form mostly between 8 and 15 years and one-sided occurring frequently with premature closure of the growth plate as well as necrosis of the adjacent epiphysis.

Must be differentiated deformities due to rickets and premature physeal closure of other, mostly post-traumatic etiology.

Classification

After Langeskjöld different prognosis and therapy relevant stages can be distinguished:

• Stage I: varus deformity with irregularity of the growth plate and medial side hook formation
• Stage II: reduction of the medial tibial metaphysis with a slight tilt
• Stage III: Significant varus and pronounced medial hooks, possibly fragmentation of the medial metaphysis
• Stage IV: narrowing of the growth plate with a clear inclination
• Stage V: Additional deformation and division of the epiphysis
• Stage VI: bridging between epi- and metaphysis medially with partial fusion of fragmented epiphysis to the metaphysis.

Treatment

Treatment is usually conservative with rails.