The issues of standing up, walking and load bearing capacity during the lengthening period are not related to the intramedullary nail. The distal segment of the intramedullary nail is not locked in surgery. In other words, all of the body weight is on the external fixator. Ilizarov or monorail external fixators and pins already have a very high body weight bearing capacity. So yes, you can get up and walk on the second day of the surgery. Walking with full body weight without using a walker may be inconvenient in terms of loosening the pin sites, not in terms of carrying capacity. After the lengthening period is over, the distal part of the intramedullary nail is locked with screws and the external fixator is removed. During the consolidation period, the entire body weight is on the nail. In this period, walking without support with full body weight before the callus tissue hardens enough may be a matter of discussion.