The clinical value of tip apex distance (TAD) rule in proximal femoral nail antirotationⅡ(PFNAⅡ) in treating unstable femoral intertrochanteric fracture

ZHAO Ting-bo; JI Lu-hong; TANG Huan

doi:10.3969/j.issn.1009-4237.2016.11.006

Abstract：Objective To investigate the influence of tip apex distance ( TAD) rule on the effectiveness and safety of proximal femoral nail antirotationⅡ( PFNAⅡ) in unstable femoral inter-trochanteric fracture.Meth-ods A total of 162 unstable femoral inter-trochanteric fractures patients that had undergone PFNAⅡin our hospital were retrospectively evaluated.One hundred and one cases were males and 61 were females[mean age 68.1(57-84) years] .Totally 137 cases were injured from falling and 25 cases were from traffic accident.They were divided into TAD≤25mm group(102 cases) and TAD>25mm group(57 cases) according to TAD rule.Comparison between the two groups was based on four indicators,including weight-bearing time,fracture healing time,post-operative com-plication rate and post-operative Harris score for the fractured hip.Results Three patients were excluded because of non-operation related death.They remaining 159 patients were followed up for an average of 14.1 months,ranging from 10 to 22 months.Within the study period,20 patients had surgical complication,and one of them accepted sec-ondary femoral head arthroplasty for the helical blade cut-out.They achieved good clinical recovery with average weight-bearing time of (6.4 ±1.8) weeks,average fracture healing time of (5.4 ±1.3) months and average post-operative Harris score of (86.7 ±5.0) points.However,the two groups had no statistical difference in fracture heal-ing time,post-operative complication rate and post-operative Harris score(P>0.05).Conclusion PFNAⅡis ef-fective in treating unstable femoral inter-trochanteric fractures.But there is no enough evidence showing that the TAD rule is still applicable to PFNA/PFNAⅡ.