Reduced dislocation rate after hip arthroplasty for femoral neck fractures when changing from posterolateral to anterolateral approach.
OBJECTIVE
Recent studies have shown that compared to the posterolateral approach, the anterolateral approach reduces the risk of dislocation after hip arthroplasty in patients with femoral neck fractures. We have therefore started to use the anterolateral approach on these patients and we now report the consequences of this change for the dislocation rate.


METHODS
We chose two 1-year time periods, 2007 (n = 199) and 2008 (n = 173), the former being before and the latter after the implementation of the anterolateral approach as the standard incision for hip arthroplasties in patients with femoral neck fractures. During 2007, 77% of the hips were operated on with the posterolateral approach and in 2008, 78% of the hips were operated on using the anterolateral approach.


RESULTS
The dislocation rate was reduced from 8% (16/199) in 2007 to 2% (3/173) in 2008. A multivariable logistic regression analysis showed that the posterolateral approach was the only factor associated with an increased risk of dislocation, with an odds ratio of 8 (2–35). Age, sex, ASA classification, type of arthroplasty, cognitive dysfunction, or the experience of the surgeon had no effect on the risk of dislocation.


CONCLUSIONS
Since most of our surgeons had earlier used the posterolateral approach when performing hip arthroplasties in patients with a femoral neck fracture, this study shows our surgical learning curve. We conclude that a collective policy change regarding surgical approach for these patients is both feasible and to be recommended, as it leads to a substantial reduction in dislocation rate.
Sköldenberg
Olof
O
Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, Stockholm, Sweden. olof.skoldenberg@ds.se
Ekman
Anna
A
Salemyr
Mats
M
Bodén
Henrik
H
D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000379:methods; D015331:Cohort Studies; D005260:Female; D005265:Femoral Neck Fractures / Q000601:surgery*; D006617:Hip Dislocation / Q000209:etiology / Q000601:surgery; D006622:Hip Prosthesis / Q000009:adverse effects; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011475:Prosthesis Failure; D012086:Reoperation; D012307:Risk Factors