Subspine Hip Impingement: Clinical and Radiographic Results of its Arthroscopic Treatment

Abstract

Objective To evaluate the clinical and radiographic results as well as complications related to patients undergoing arthroscopic treatment of subspine hip impingement. Methods We retrospectively evaluated 25 patients (28 hips) who underwent arthroscopic treatment of subspine impingement between January 2012 and June 2018. The mean follow-up was 29.5 months, and the patients were evaluated clinically by using the Harris hip score modified by Byrd (MHHS), the non-arthritic hip score (NAHS), and in terms of internal rotation and hip flexion. In addition, the following items were evaluated by imaging exams: the center-edge (CE) acetabular angle, the Alpha angle, the presence of a sign of the posterior wall, the degree of arthrosis, the presence of heterotopic hip ossification, and the Hetsroni classification for subspine impingement. Results There was an average postoperative increase of 26.9 points for the MHHS, 25.4 for the NAHS ( p < 0.0001), 10.5° in internal rotation ( p < 0.0024), and 7.9° for hip flexion ( p < 0.0001). As for the radiographic evaluation, an average reduction of 3.3° in the CE angle and of 31.6° for the Alpha angle ( p < 0.0001). Eighteen cases (64.3%) were classified as grade 0 osteoarthritis of Tönnis, and 10 (35.7%) were classified as Tönnis grade 1. Two cases (7.1%) presented grade 1 ossification of Brooker. Most hips ( n = 15, 53.6%) were classified as type II of Hetsroni et al. Conclusion In the present study, patients undergoing arthroscopic treatment with subspine impingement showed improvement in clinical aspects and radiographic patterns measured postoperatively, with an average follow-up of 29.5 months.

Keywords: arthroscopy; femoroacetabular impingement; hip joint.

Fig. 1

Preoperative radiography in anteroposterior view of the hip joint, showing the presence of prominent anterior inferior iliac spine (white arrow) and deformity in the neck-head transition (asterisk). center-edge Angle: 36°.

Fig. 2

Preoperative radiography in DUNN view 45° evidencing the presence of cam-type deformity. Alpha angle: 80°.

Fig. 3

Preoperative image of computed tomography in axial section, showing the presence of prominent anterior inferior iliac spine (white arrow).

Fig. 4

Two-year postoperative radiograph in anteroposterior view of the hip joint, showing the correction of the subspine impingement and of the deformity of the neck-head transition.

Fig. 5

Two-year postoperative radiograph in DUNN 45° view showing the correction of the cam-type deformity. Alpha angle: 38°.

Fig. 1

Radiografia pré-operatória em incidência anteroposterior de articulação coxofemoral, evidenciando a presença de espinha ilíaca anteroinferior proeminente (seta branca) e deformidade na transição colo-cabeça (asterisco). Ângulo CE: 36°.

Fig. 2

Radiografia pré-operatória em incidência DUNN 45° evidenciando a presença de deformidade tipo came. Ângulo alfa: 80°.

Fig. 3

Imagem pré-operatória de Tomografia computadorizada em corte axial, evidenciando a presença de espinha ilíaca anteroinferior proeminente (seta branca).

Fig. 4

Radiografia pós-operatória de 2 anos em incidência anteroposterior de articulação coxofemoral, evidenciando a correção do impacto subespinhal e da deformidade da transição colo-cabeça.

Fig. 5

Radiografia pós-operatória de dois anos em incidência DUNN 45° evidenciando a correção da deformidade tipo came. Ângulo alfa: 38°.