From the Research
The distal fibula physis typically closes between 15 and 18 years of age in females and 17 to 20 years of age in males. This growth plate is one of the last to close in the body, which is important to recognize when evaluating ankle injuries in adolescents. The closure occurs as part of normal skeletal maturation when cartilage cells in the physis stop proliferating and the growth plate ossifies, becoming solid bone. This process is primarily driven by hormonal changes during puberty, particularly sex hormones like estrogen and testosterone, which explains the earlier closure in females compared to males 1.
Key Points to Consider
- The distal fibular physis begins as a transverse structure that becomes undulated and has extensive peripheral lappet formation 1.
- Enchondromalike extensions of the physis into the metaphysis are common, and accessory ossification may develop at the distal end 1.
- Clinically, this information is crucial when assessing ankle injuries in adolescents, as an open physis can be vulnerable to Salter-Harris fractures that may affect future growth 2.
- Radiologists and orthopedic surgeons use this knowledge when interpreting imaging studies to distinguish normal growth plates from fractures and when planning treatments that might affect growth in skeletally immature patients 3.
Implications for Clinical Practice
- The physical examination is unreliable in determining the location of the distal fibular physis, and imaging studies such as ultrasound or MRI may be necessary to accurately assess the growth plate 2.
- Growth arrest in the distal fibular physis may result in either proximal or distal sliding of the fibular metaphysis in relation to the tibial metaphysis, which can lead to valgus deformity of the ankle 4.
- Histological and radiographic determination of the age of physeal closure of the distal femur, proximal tibia, and proximal fibula of the New Zealand white rabbit has been studied, but the results may not be directly applicable to humans 5.