The relationship between morphometric parameters and Trendelenburg sign following the Hardinge incision.

Objectives: We evaluated the relationship between morphometric parameters such as height, weight, and body mass index with the development of the Trendelenburg gait following the Hardinge approach, which is one of the most commonly used approaches in total hip arthroplasty.

Methods: The study included 59 patients (43 women, 16 men; mean age 55 years; range 37 to 74 years) who underwent total hip arthroplasty via the Hardinge approach for primary coxarthrosis. The patients were examined postoperatively at 15 days, and at the end of the first and third months. The mean follow-up period was 24.3 months (range 12 to 37 months). The height, weight, and body mass index values of the patients with and without a positive Trendelenburg sign were compared.

Results: The Trendelenburg sign was positive in 19 patients (32.2%) following total hip arthroplasty with the Hardinge approach and persisted for a mean of 8.3 months (range 4-14 months). Patients with a positive Trendelenburg sign had a mean height of 157.4 cm (range 151 to 173 cm), mean weight of 82.5 kg (range 70 to 108 kg), and mean body mass index of 33.2 kg/m(2) (range 25.4 to 30.5 kg/m(2)). The corresponding figures in patients without a Trendelenburg sign were as follows: 166.3 cm (range 158 to 180 cm), 79.4 kg (range 72 to 94 kg), and 28.7 kg/m(2) (range 21.6 to 30.5 kg/m(2)). There was no significant difference between the two patient groups with respect to weight, but height and body mass index showed highly significant differences (p<0.0001).

Conclusion: Based on our finding that patients having a significantly shorter height and greater body mass index sustained Trendelenburg positivity for quite a long time, we recommend that these two factors be taken into consideration in the preoperative evaluation of patients for total hip arthroplasty with the Hardinge approach. Thus, the use of the Hardinge approach in total hip arthroplasty may not be convenient in short subjects having borderline obesity.