Proliferation analysis of the growth plate after diaphyseal midshaft fracture by 5′-bromo-2′-deoxy-uridine
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Both stimulative and inhibitory growth disturbances may occur after a fracture during the growth period. The exact mechanism responsible for stimulative growth disturbances in the immature skeleton is unexplained. It's possible that chondrocyte proliferation leads to overgrowth. This study investigates the effect of a fracture on the proliferation of chondrocytes at the nearby growth plate and its effect on the contra-lateral leg. Fifty-six 1-month-old Sprague–Dawley rats (weight, 100–120 g) were randomised to either an experimental or a control group. A closed mid-diaphyseal tibial fracture was produced in all animals of the experimental group using a standardised technique. On day 3, 10, 14 and 29 of the experiment, the rats were euthanised and their tibial growth plates were subjected to histological analysis. 5′-Bromo-2′-deoxy-uridine labelling was used for the quantitative analysis of chondrocyte proliferation. Safranin O staining provided the histological overview for the subsequent analysis of BrdU-labelling. Immunohistochemical analysis showed increased proliferation of chondrocytes in the growth plates of broken bones during fracture healing. This proliferation peaked on day 3 post-fracture and then reduced gradually until day 29. No increase in the rate of proliferation was observed on the contra-lateral limbs of the animals in the experimental group. Following a diaphyseal fracture of the tibia, the growth plates located next to the fracture react with increased cell proliferation. This proliferation was not observed in the contra-lateral uninjured tibia. This investigation shows that the post-traumatic length discrepancy is a local biological process at the growth plate brought about by the fracture.
KeywordsGrowth plate Chondrocyte proliferation Growth disturbance Bone length discrepancy 5′-Bromo-2′-deoxy-uridine
This study was supported by a grant from the AO Research Foundation, Switzerland. Furthermore, we want to thank Andrea Groselj-Strele M.Sc., Office for Biostatistics, Center for Medical Research, Medical University of Graz, for her support concerning the statistical processing.
Conflict of interest statement
The authors declare that they have no conflict of interest.
- 2.Clement DA, Colton CL (1986) Overgrowth of the femur after fracture in childhood. An increased effect in boys. J Bone Jt Surg Br 68:534–536Google Scholar
- 3.Reynolds DA (1981) Growth changes in fractured long-bones: a study of 126 children. J Bone Jt Surg Br 63-B:83–88Google Scholar
- 4.Stephens MM, Hsu LC, Leong JC (1989) Leg length discrepancy after femoral shaft fractures in children. Review after skeletal maturity. J Bone Jt Surg Br 71:615–618Google Scholar
- 10.Ogden JA (2000) Skeletal injury in the child. Springer-Verlag, New YorkGoogle Scholar
- 11.Pring M, Newton P, Rang M (2005) Femoral shaft. In: Rang M, Pring ME, Wenger DR (eds) Rang's children's fractures. Lippincott Williams & Wilkins, Philadelphia, PA, pp 181–200Google Scholar
- 12.Rang M, Wenger DR (2005) Children are not just small adults. In: Rang M, Pring ME, Wenger DR (eds) Rang's children's fractures. Lippincott Williams & Wilkins, Philadelphia, PA, pp 1–10Google Scholar
- 13.Routt M Jr (1994) Fractures of the femoral shaft. In: Green N, Switontkowski M (eds) Skeletal trauma in children. WB Saunders Company, Philadelphia, pp 345–368Google Scholar
- 14.Salter R (1983) Textbook of disorders and injuries of the musculoskeletal system. Williams & Wilkins, Baltimore, MDGoogle Scholar
- 15.Wirth T, Syed Ali MM, Rauer C et al (2001) The influence of local vascular regeneration on growth plate activity after defined growth plate lesions. Eur J Trauma 27:58–65Google Scholar
- 22.Standring S, Ellis H, Healy JC et al (2005) Gray's anatomy: the anatomical basis of clinical practice. Elsevier Churchill Livingstone, EdinburghGoogle Scholar
- 23.Ballock RT, O'Keefe RJ (2003) The biology of the growth plate. J Bone Jt Surg Am 85-A:715–726Google Scholar
- 26.Meyer U, Wiesmann HP (2006) Bone and cartilage engineering. Springer-Verlag, BerlinGoogle Scholar