[Connecting adapter for coupling exoprostheses to endoshafts : Demands on orthopedic technicians with respect to planning and application]

Abstract

Introduction: Transcutaneous, bone anchored prostheses have proved to be an alternative for amputees. In addition to the safe osseointegration of the implant, the correct prosthetic alignment is also important. Therefore, the interaction between prosthesis components and the prosthesis wearer is significant and the role of the certified prosthetist should not be underestimated.

Aim: The aim of treatment is the best possible compensation of disability after limb loss with increase of physical abilities and comfort of the prosthesis wearer by means of bone anchored prosthesis.

Method: Endoprosthesis inserted by the surgeon carrying out both surgery with the implant and a double-cone and 6 weeks later the exoprosthesis is fitted by the certified prosthetist orthotist (CPO). Mounting the external adaptors, assembly of the prosthesis.

Results: The long-term results with cementless implants and more than 35 years experience are presented. Clinical experience with the endo-exo prosthesis since 1999. A total of 135 patients treated after transfemoral amputation, 8 of them bilateral, 8 out of 135 were transtibial amputees and 1 of them bilateral. A total of 85% were amputated as a consequence of trauma and 12 out of 135 had a full range of motion at the beginning of the prosthetic work following osseointegration. In other cases, a hip flexion contracture between 3 and 12 ° had to be considered by corresponding posterior displacement adaptors.

Conclusion: Bone anchored prostheses influence the skeleton and joints in a more direct way. This fact requires specific prosthetic measures concerning the connection between the endo-implant and the exoprosthesis. Therefore, specially matched adaptors and the prosthetic alignment are the focus of interest. Prostheses connected to an osseointegrated implant have many biomechanical advantages compared to socket-guided prostheses. Because the quality of rehabilitation is clearly affected by the prosthetic alignment, it has to be carried out extremely carefully and precisely if the prosthesis is connected to an osseointegrated implant. According to the survey, none of the prosthesis wearers wanted to return to a socket-guided prosthesis.

Keywords: Amputation; Biomechanics; Osseointegration; Prosthesis; Prosthetic alignment.