The aim of a study that spanned 15 years was to describe implant and patient-reported outcomes in patients with a unilateral transfemoral amputation treated with a bone-anchored, transcutaneous prosthesis.
All participants were treated with the Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA) implant system in Sahlgrenska University Hospital, Gothenburg, Sweden, between January 1999 and December 2017. The cohort comprised 111 patients (78 men or 70 percent) with a mean age of 45 years (17 to 70). The main reason for amputation was trauma in 75 patients (68 percent) and tumors in 23 patients (21 percent).
Patients answered the Questionnaire for Persons with Transfemoral Amputation (Q-TFA) before treatment and at two, five, seven, ten, and 15 years’ follow-up. A prosthetic activity grade was assigned to each patient at each timepoint. All mechanical complications, defined as fracture, bending, or wear to any part of the implant system resulting in removal or change, were recorded.
Results of the study showed that the Q-TFA scores at two, five, seven, and ten years showed significantly more prosthetic use, better mobility, fewer problems, and an improved global situation, compared with baseline. The survival rate of the osseointegrated implant was 89 percent after seven years and 72 percent after 15 years. Sixty-one patients (55 percent) had mechanical complications resulting in exchange of the percutaneous implant parts, according to the study. There was a positive relationship between a higher activity grade and the number of mechanical complications.
Compared with before treatment, the patient-reported outcome was significantly better and remained so over time, the study found. Although osseointegration and the ability to transfer loads over a 15-year period have been demonstrated, a number of mechanical failures in the external implant parts were found. Since these were related to higher activity, restrictions in activity and improvements to the mechanical properties of the implant system are required.
The study was published in December in the Bone & Joint Journal.