Leg lengthening by distraction osteogenesis using the Ilizarov apparatus: a novel concept of tibia callus subsidence and its influencing factors

Abstract

This article studies the incidence and magnitude of delayed callus subsidence, which will also help in study the hypothesis of three cortex corticalisation to determine the time of fixator removal during distraction osteogenesis (DO). Eighty-one tibia segments with mean lengthening of 7.7±2.9 cm were studied with age, gender, skeletal maturity, amount and percentage of lengthening, callus pattern, callus shape, number of cortices seen at the time of fixator removal, bone mineral density (BMD) ratio, and callus diameter ratio analysed for their effect on callus subsidence. All segments had tibia callus subsidence ranging from 4 mm to 3.2 cm with 54% having significant subsidence of more than 1 cm. Multivariate regression analysis revealed only the amount of lengthening and callus patterns to be significant. In conclusion, we can say that tibia callus subsidence is a significant delayed complication and factors affecting it can be used to determine the time of fixator removal.

Complications and outcome of tibial lengthening using the Ilizarov method with or without a supplementary intramedullary nail

“…A previous study showed that callus subsidence often goes unnoticed by surgeons in spite of the high incidence. 18 It is caused by inadequate callus formation and early weight-bearing, which can also cause axial deviation. Laxity of the knee and ankle and THE JOURNAL OF BONE AND JOINT SURGERY subluxation of the fibular head are more occult complications that many surgeons also overlook.…”

“…Its measurement and calculation has been well described. [14][15][16][17][18][19][20] The healing index records the time needed to reach a certain level of bone quality for the regenerate. The lower the value, the more ideal the regeneration.…”

Author's reply to comments on Shyam et al.: Leg lengthening by distraction osteogenesis using the Ilizarov apparatus: a novel concept of tibia callus subsidence and its influencing factors

“…We really appreciate the thoughtful and detailed comments by the readers in referencing our paper on subsidence in tibia lengthening [1].…”

Distraction osteogenesis using a longitudinal corticotomy

“…To decrease the amount of time the external fixator was in place, it was often exchanged for a cast prior to complete consolidation. Healing duration was defined as time from the beginning of lengthening until bony consolidation, which was defined by formation of complete cortices at least 2 mm in diameter (three mm for lengthenings under ten centimetres and four mm for lengthening over ten centimetres), as previously described [16,18]. The healing index (healing duration per centimetre of lengthening) was calculated for each patient, and any complications were noted.…”