A Modelling Capacity of Vertebral Fractures Exist During Growth: An Up To 47 Years Follow-up

Introduction: The purpose of the study was to evaluate the incidence and the long-term results of vertebral fractures sustained during growth.

Material and Methods: At Malmo University Hospital, the only emergency hospital in the city of 225 00 inhabitants, all radiographs are saved since the beginning of last century leaving the opportunity to re-examine and classify old fractures. All patients with a traumatic vertebral fracture 1950-1972, <16 years at injury, still alive and city residents were invited. Three denied to participate, leaving 12 boys and 12 girls with mean age 12 years (range 7 – 16) when sustaining the fracture, 21 stable one column compression fractures and 3 burst fractures Denis type B, all without neurological deficits. The primary treatment consisted in all of immediate mobilisation without any support. The follow-up after mean 33 years (range 27 – 47) included subjective symptoms (Oswestry score), objective deficits (Frankel score) and radiographic outcome. Outcome are presented as mean ± SD.

Results: Epidemiology:The incidence of thoracolumbar vertebral fractures in individuals below age 16 in Malmo, Sweden, was during the period 1950 – 1971, 0.7 / 10 000 person-years (0.07 ‰).

Subjective: Twenty-one individuals had at follow-up no subjective complaints, three had occasional back pain (Oswestry Scores 8, 22, 26, respectively). All were classified as Frankel E and al were fulltime working.

Objective: All had normal lumbar lordosis and thoracic kyfosis. One had reduced quadriceps strength in one leg but no muscle atrophy. No other deficits were seen.

Radiographic: The radiographic ratio anterior height / posterior height in the fractured vertebra increased from 0.75 at fracture event to 0.87 at follow-up (p < 0.001) and the posttraumatic kyfosis in the fractured region decreased in 8 individuals (33 %), all aged 13 or less at fracture event. No increased disc degeneration were seen above or below the fractured vertebra and none had developed olisthesis or scoliosis.

Conclusion: Vertebral fractures without neurological deficits, sustained during growth, have an excellent long-term outcome. A modelling capacity, reducing the fracture deformity, exists at least in the youngest patients.