Objective    To investigate the relationship between the anatomic form of proximal femoral medullary cavity and the proximal femoral fracture caused by the implantation of Ribbed anatomic femoral stem.     Methods    Between Jan. 2004 and Jan. 2009

we performed total hip arthroplasty on two-hundred-and-thirteen patients (two-hundred-and-fifty-four hips) using the Link Ribbed femoral stems. Before the surgeries

the anatomic form of proximal femoral medullary cavity of each patient was analyzed and classified. After the surgeries

we followed-up all patients for 1-5 years (average=3.6 years)

and evaluated their hip joint function by Harris scoring.     Results    One-hundred-and-seventy-six patients (82.63%) had a normal proximal femoral medullary cavity; twenty patients (9.39%) had a champagne-flute type proximal femoral medullary cavity; only seventeen patients (7.98%) had a stovepipe type proximal femoral medullary cavity. Proximal femoral fracture occurred in eleven patients (including five patients with femoral neck fracture and six patients with greater trochanter fracture)

accounting for 5.16% of all patients and 26.19% of all complications. Seven of the eleven patients with proximal femoral fracture had a champagne-flute type proximal femoral medullary cavity (63.64%). No aseptic loosening of Ribbed femoral stem was found. Two-hundred-and-three patients (95.31%) could engage in the former jobs

and one-hundred-and-ninety-five patients could squat down and wear shoes and socks. The average Harris score of the patients after the surgeries was significantly higher than that before the surgeries (93.0 vs 40.8).     Conclusion    The anatomic form of proximal femoral medullary cavity is related to the proximal femoral fracture caused by the implantation of anatomic Ribbed femoral stem

and can contribute to the difficulty of the implantation. Therefore

the anatomic form of proximal femoral medullary cavity should be taken into account when selecting the anatomic implant.