Spinopelvic sagittal alignment of people with a transfemoral amputation

Abstract

This study aims to describe the spinopelvic sagittal alignment in transfemoral amputees (TFAs) and to compare with a reference population. To our knowledge, this is the first recent radiologic study of the TFAs’ spine and the first postural approach destined to better understand the high prevalence of low back pain (LBP) in the TFAs. Volunteers with transfemoral amputation underwent bi-planar X-rays with 3-D reconstructions of the spine and pelvis. Sagittal parameters were analyzed in the light of literature and compared to those of a reference group of non-amputees. Differences between TFAs with and without LBP were also searched. Twelve subjects have been prospectively included. The two groups (TFA-LBP n = 5 and TFANoP n = 7) were comparable in terms of gender, age, amputation delay and sedentarity. In the TFALBP group, the impact of LBP was estimated on average to 16.4% with the ODI (SD 7.9%, [6; 24]). Pelvic incidences were within normal limits, except for one subject of the TFA-LPB group. Anterior pelvic tilt was observed in two subjects of each group. Eight subjects (6 NoP and 2 LBP) had abnormal low value of TK. The mean angle of TK in the TFA-NoP group was lower than in the TFA-NoP group ( P = 0.0511). Two subjects of the TFA-LBP group had a hyperlordosis while all the TFAs-NoP had a lower lumbar lordosis than expected in an economic posture. Concerning the sagittal balance, four of the five individuals of the TFA-LBP group had unbalanced sagittal posture versus two of the seven in TFAs-NoP. This study emphasizes the importance of considering the sagittal balance of patients with a transfemoral amputation to prevent and manage the onset of low back pain. Moreover, in this population, it seems necessary to study not only the sagittal plane but also the frontal plane, which is also probably unbalanced.