Prevalence of Osteoarthritis in Patients Undergoing Transfemoral Amputation

A significantly decreased prevalence of osteoarthritis (OA) and specific disorders of the spine have been observed in patients undergoing unilateral transfemoral amputation compared with controls, according to database analysis results published in PLoS One.

The primary objective of the analysis was to explore whether individuals who undergo amputation are more often affected by gonarthrosis, coxarthrosis, or polyarthrosis, as well as back pain or spinal disorders. The hypothesis was that mobile and active patients undergoing transfemoral amputation more frequently experience OA and spinal disorders than non-amputees. The secondary study objective was to compare the mean age of the individuals with OA.

Overall, 1569 patients who had undergone a transfemoral amputation and 5 able-bodied control groups (n=1569 for each) were matched in terms of age, gender, and drug expenses, yielding a total of 9414 study participants. The mean age of all groups was 63.3 years, which is approximately 20 years older than the median age of the German population (approximately 44.5 years).

The groups were analyzed with respect to the prevalence of 6 selected diagnoses, based on the following musculoskeletal disorders: polyarthrosis (arthrosis with mention of >1 side), coxarthrosis (arthrosis of the hip), gonarthrosis (arthrosis of the knee), spinal osteochondrosis, other deformities of the spine, and back pain. For all of the 6 selected musculoskeletal disorders, the number of insured individuals in the control group was higher than that in the group undergoing transfermoral amputation.

The study results showed a significantly decreased prevalence of OA and specific disorders of the spine in patients undergoing transfemoral amputation compared with controls with respect to all diagnoses other than gonarthrosis. Regarding polyarthrosis, 4.72% insured in the transfemoral amputation group and 7.07% insured in the control group were affected (P =.006). In addition, a total of 11.22% of patients in the amputation group and 13.64% of patients in the control group were affected by coxarthrosis (P =.045).

Regarding the diagnosis of spinal osteochondrosis, patients in the transfemoral amputation arm were affected significantly less often than patients in the control arm (7.84% insured vs 12.36% insured, respectively; P ≤.001). Moreover, the lowest number of insured were affected by other deformities of the spine (3.89% in amputees vs 5.80% in controls; P =.016). In addition, the patients in the fermoral amputation group were significantly less affected by back pain than patients in the control group (P ≤.001).

The investigators concluded that life circumstances, such as physical work and strenuous activities, which were likely to be underrepresented in the amputation group, played a key role in the findings from the study. The amputees with OA were significantly younger than patients with OA in the control group.

Study results should be interpreted with caution, however, because of the lack of details available with respect to individual patients linked to the methodology of this analysis.

Reference

Welke B, Jakubowitz E, Seehaus F, et al. The prevalence of osteoarthritis: Higher risk after transfemoral amputation?-A database analysis with 1,569 amputees and matched controls. PLoS One. 2019;14(1):e0210868.