Cozen fracture or phenomenon is the valgus angulation deformity of the tibia following a proximal tibial metaphyseal fracture in children.
This typically occurs as a late deformity in children aged 3-6 years.
Proposed causes include:
- non-recognized or under recognized valgus deformation at time of injury
- proximal tibial fractures in children typically involved valgus force resulting in laterally angulated distal tibia
- also inadequate reduction may play a role
- soft tissue interposition of periosteum and/or pes anserinus
- medial epiphyseal overgrowth stimulated by trauma
- greenstick fracture whereby medial aspect fractured but intact lateral aspect with subsequent bowing
Treatment and prognosis
These deformities usually self correct within 12-24 months. Younger children have better remodelling potential. Surgery can be considered if the patient is older with significant angulation or if there is failure to self correct a Cozen deformity.
History and etymology
Dr Lewis N Cozen (1911-2001), American orthopedic surgeon, first described this deformity in 1953 4.
- 1. Dorman S, Jariwala A, Campbell D. Cozen's phenomenon: a reminder. (2013) Scottish medical journal. 58 (3): e10-3. doi:10.1177/0036933013496922 - Pubmed
- 2. Sanjeev Sabharwal. Pediatric Lower Limb Deformities. (2015) ISBN: 9783319170978
- 3. Yael Gelfer, Karen Daly, Deborah Eastwood. Paediatrics for the FRCS (TR + ORTH) Examination. (2018) ISBN: 9780198749301
- 4. Cozen L. Fracture of the proximal portion of the tibia in children followed by valgus deformity. (1953) Surgery, gynecology & obstetrics. 97 (2): 183-8. Pubmed