THE ANTERIOR STRESS-FRACTURE OF THE TIBIA - AN ATROPHIC PSEUDOARTHOSIS

Histopathological examination of biopsies from the fracture site in tw o cases of anterior stress fractures of the tibia demonstrated no bone remodelling activity, absence of inflammatory cells, extensive fibrot ic infiltration and local avascular bone necrosis. The biopsies were t aken peroperatively from two elite soccer players who earlier had to s top training due to severe exertional pain. When non-operative treatme nt failed to heal the fractures within 1 year and 6 months, respective ly, surgery was performed in order to stabilize the fractures. Both su bjects were relieved from exertional pain within 6 months of surgery. Consecutive radiographs showed the pattern of direct healing and 8 mon ths postoperatively confirmed complete healing without callus formatio n. Both elite soccer players returned to pre-injury activity level. We suggest that the excessive fibrotic tissue ingrowth and hypovasculari ty under repetitive stress causes the delayed healing and histopatholo gical signs similar to an atrophic pseudoarthosis. Treatment should co nsequently consider the pseudoarthrotic character of the anterior stre ss fracture of the tibia.