Background: There is a paucity of data on the treatment of femoral neck fractures in young patients. The purpose of the present study was to review the results and complications associated with the treatment of femoral neck fractures with internal fixation in a large consecutive series of young patients.

Methods: Between 1975 and 2000, eighty-three femoral neck fractures in eighty-two consecutive patients who were between fifteen and fifty years old were treated with internal fixation at our institution. Two patients died, and eight were lost to follow-up. Seventy-three fractures were followed until union, until conversion to hip arthroplasty, or for a minimum of two years; the mean duration of follow-up was 6.6 years. Fifty-one of the seventy-three fractures were displaced, and twenty-two were nondisplaced. The results and complications of treatment were retrospectively reviewed, and the effects of fracture displacement, reduction quality, and capsular decompression on outcome were evaluated. Function was assessed by evaluating pain, walking capacity, and the need for gait aids. The mean duration of follow-up for the fifty-seven patients (fifty-eight fractures) who had not undergone early conversion to arthroplasty was 8.1 years.

Results: Fifty-three (73%) of the seventy-three fractures healed after one operation and were associated with no evidence of osteonecrosis of the femoral head. Osteonecrosis developed in association with seventeen fractures (23%), and a nonunion developed in association with six (8%). Four of the six nonunions later healed after a secondary procedure. At the time of the final follow-up, thirteen patients had had a conversion to a total hip arthroplasty because of osteonecrosis (eleven), nonunion (one), or both (one). Five (9.8%) of the fifty-one displaced fractures were associated with the development of nonunion, and fourteen (27%) were associated with the development of osteonecrosis. Three (14%) of the twenty-two nondisplaced fractures were associated with the development of osteonecrosis, and one (4.5%) was associated with the development of nonunion. Eleven (24%) of the forty-six displaced fractures with a good to excellent reduction were associated with the development of osteonecrosis, and two (4%) were associated with the development of nonunion. Four of the five displaced fractures with a fair or poor reduction were associated with the development of osteonecrosis, nonunion, or both.

Conclusions: The ten-year survival rate of the native femoral head free of conversion to total hip arthroplasty was 85%. Osteonecrosis was the main reason for conversion to total hip arthroplasty, but not all patients with osteonecrosis required further surgery. The results of treatment were influenced by fracture displacement and the quality of reduction.

Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.