Late postoperative analysis of the tip-apex distance (TAD) in pertrochanteric fractures: is there an accommodation of the implant within the bone?

Abstract

This study measured the tip-apex distance (TAD) values in the immediate postoperative period and following weight-bearing and fracture impaction in patients undergoing osteosynthesis with dynamic hip screw and cephalomedullary nail. To correlate the Baumgaertner index in the immediate postoperative period with values obtained after impaction of the fracture with the accommodation of the cephalic implant in the femoral head. Radiographic TAD measurements were taken with AGFA-VIEW^® of 82 patients with a mean age of 72 years with pertrochanteric fractures who were operated on and the fracture fixed with DHS- Synthes^®, TFN-Synthes^®, or Gamma Nail III-Stryker^® in the immediate postoperative period, and following weight-bearing and fracture impaction (mean 3-8 weeks after surgery). The overall average TAD decreased from 20.3mm to 18.2mm. Regardless of the instability of the fracture, the age of the patient or the implant used, TAD decreased between the immediate postoperative period and following fracture impaction. The osteosynthesis of pertrochanteric fractures was associated with important accommodation of the cephalic implant in the femoral head with decreased TAD values after weight-bearing.