A system for engaging a proximal end of an intramedullary nail , comprising: (i) a driver comprising a handle extending along a longitudinal axis (L1) of the driver from a proximal end to a distal end and having a handle channel extending longitudinally therethrough, a shaft extending through the handle channel from a proximal end to a distal end along the longitudinal axis (L1) having a shaft channel extending longitudinally therethough, the distal end of the shaft extending distally from the handle , the distal end of the shaft forming a driving element , and a retention pin slidably received in the shaft channel and extending from a proximal end to a distal end along the longitudinal axis (L1), the distal end of the retention pin comprises threading, the retention pin including a lumen extending longitudinally therethrough; (ii) an endcap having a lumen extending therethrough comprising a body configured to engage a channel of the intramedullary nail , and a head portion configured to receive the driving element therein and to reversibly lock the head portion to the shaft , the head portion comprising threading configured to threadedly engage a corresponding threading of the retaining pin ; and (iii) a guidewire slidably inserted through the lumen of the retention pin and the lumen of the endcap to align the driving element to the head portion of the endcap . (i) a driver comprising a handle extending along a longitudinal axis (L1) of the driver from a proximal end to a distal end and having a handle channel extending longitudinally therethrough, a shaft extending through the handle channel from a proximal end to a distal end along the longitudinal axis (L1) having a shaft channel extending longitudinally therethough, the distal end of the shaft extending distally from the handle , the distal end of the shaft forming a driving element , and a retention pin slidably received in the shaft channel and extending from a proximal end to a distal end along the longitudinal axis (L1), the distal end of the retention pin comprises threading, the retention pin including a lumen extending longitudinally therethrough; a handle extending along a longitudinal axis (L1) of the driver from a proximal end to a distal end and having a handle channel extending longitudinally therethrough, a shaft extending through the handle channel from a proximal end to a distal end along the longitudinal axis (L1) having a shaft channel extending longitudinally therethough, the distal end of the shaft extending distally from the handle , the distal end of the shaft forming a driving element , and a retention pin slidably received in the shaft channel and extending from a proximal end to a distal end along the longitudinal axis (L1), the distal end of the retention pin comprises threading, the retention pin including a lumen extending longitudinally therethrough; (ii) an endcap having a lumen extending therethrough comprising a body configured to engage a channel of the intramedullary nail , and a head portion configured to receive the driving element therein and to reversibly lock the head portion to the shaft , the head portion comprising threading configured to threadedly engage a corresponding threading of the retaining pin ; and a body configured to engage a channel of the intramedullary nail , and a head portion configured to receive the driving element therein and to reversibly lock the head portion to the shaft , the head portion comprising threading configured to threadedly engage a corresponding threading of the retaining pin ; and (iii) a guidewire slidably inserted through the lumen of the retention pin and the lumen of the endcap to align the driving element to the head portion of the endcap . <EOS>