Original Title: État des connaissances - Ostéointégration de prothèses à ancrage osseux chez les personnes vivant avec une amputation d’un ou des membres inférieurs

Authors' objectives: The Institut national d'excellence en santé et en services sociaux (INESSS) was mandated by the Ministère de la Santé et des Services sociaux (MSSS) to produce a state of knowledge on osseointegration of bone-anchored prostheses (BAP) in people living with lower limb amputations. This state of scientific knowledge presents a synthesis of all the evidence from the literature, a portrait of the experience in Quebec since the beginning of the project in 2019, as well as the perspectives of stakeholders. It aims to highlight the findings and issues related to this type of innovative technology.

Authors' results and conclusions: RESULTS: (#1 SOCIO-CULTURAL DIMENSION): OI is a new support option for people living with an amputation of one or two lower limbs. In Quebec, the rapid integration of highly potential innovations remains a major objective of the government. However, it is important that OI integration must be based on a rigorous assessment of its benefits and risks, as well as its impact on the sustainability of health and social services systems. (#2 POPULATIONAL DIMENSION): Diabetes and vascular disease, which are exclusion criteria for OI, are the two leading causes of lower limbs amputations (65.4% and 25.6%, respectively). Lower limb(s) amputation involves a physical and environmental reconfiguration as well as an identity reconfiguration that is noticeable daily and extends throughout life. The main option for patients to regain some level of functionality and mobility is a prosthetic socket. There are different types of prostheses, from the most basic to the most sophisticated ones. Daily use of a prosthetic socket may require numerous adjustments, revisions, and replacement of its components. Some people continue to experience problems and complications with their prosthesis and have no other options except its usage. BAPs are designed to provide a more physiological gait and posture, improve the range of motion and control, and increase osteo-perception. (#3 CLINICAL DIMENSION): Approximately 50 clinical studies evaluating BAPs have been published since the first trials in 1990. However, many of these studies have methodological concerns. For instance, the type of program or BAP used is not always specified in these studies. In addition, similar cohorts of patients seem to be used in several studies with no mention of that. Currently, it is difficult to determine the actual number of osseo-integrated patients and their long-term follow-up. A 2020 review estimated that approximately 400 patients received OPRA BAP and more than 800 received OPL BAP (the two most commonly used BAPs to date). The study assessing OPRA BAP, which has the longest follow-up available to date, reports data for only 14 patients at 15 years. For OPL, clinical studies report follow-ups of around 5 years, with a limited number of patients. (#4 RESULTS ON EFFICACY AND QUALITY OF LIFE ): In the studies, outcomes are compared to the patients' baseline status with prosthetic sockets and their observed complications. Overall, the clinical studies suggest that patients had improved functionality, range of motion, and comfort with their prosthesis regardless of the OI program used or the type of BAP received. In contrast, no significant improvement in social, mental, and emotional health was perceived by patients based on scores from questionnaires assessing their quality of life. The studies do not provide an explanation for this absence of improvement. Patients’ perspectives from clinical studies have identified the first few years after OI as a real challenge in rehabilitation and BAP appropriation. They would have to demonstrate a certain degree of determination, patience, and caution. According to these patients, even with the best care provided and sophisticated external prostheses, one must be mentally prepared to overcome the challenges that can occur after OI surgery. (#5 SAFETY): The most common complications after receiving a BAP are superficial infections at the site where the skin meets the external part of the implant and mechanical failure of the implant that requires replacement of certain components. The most serious complications are deep or bone infections, insufficient osseointegration and bone fractures. These can lead to implant removal or even re-amputation over the residual limb. With OPRA BAP, the risk of developing osteomyelitis within 10 years of surgery was 20% according to one study and the risk of this deep infection leading to implant removal was 9%. The older the placement of the BAP, the greater the risk of complications that require revision. After 10 years, the complications seem to become more frequent (particularly mechanical breakage and bone fracture). For the OPRA prosthesis, the survival rate (estimated number of implants still functional in the bone) remains high and stable for the first 5 years after surgery, then decreases to 89% at 7 years, 83% at 10 years, and finally 72% at 15 years. According to one study, the survival rate of the ILP implant is 78% at 9 years. No study has reported the survival rate of the ILP implant. Intensity and duration of BAP use, overweight, and female gender have been reported as risk factors for fractures. According to patient perspectives from the literature, the risks of falls, mechanical breakage, or infection remain daily concerns. (#6 ECONOMIC DIMENSION): According to the publication of Health Quality Ontario (HQO) on the efficiency of OI identified in the literature, which was deemed applicable to the Quebec clinical context, the implementation of a BAP is associated with an incremental cost-utility ratio of approximately $100,000 per QALY (quality-adjusted life year) compared to a prosthetic socket over a lifetime. The studied technology would be more expensive than the prosthetic socket but would be associated with additional benefits. Thus, if an analysis of the cost effectiveness of OI in patients with lower limb amputations in Quebec were to be performed, it seems reasonable to anticipate results that would be comparable to those reported in the HQO assessment report. (#7 ORGANIZATIONAL DIMENSION): Various findings and considerations from the international experience in OI have been identified in the literature and their applicability to the context in Quebec has been considered. Among these, we note the prudent selection of patients, which is an important preliminary step that can reduce certain long-term complications. As such, the eligibility criteria of the Montreal OI Clinic should allow specialists to properly refer their patients to the procedure. The potential increase in the number of patients who may require OI also raises uncertainty about the ability to provide optimal service and followup across the province. The current centralization of OI expertise in Montreal and the importance of knowledge transfer to health professionals in remote areas are factors to consider. For many countries, OI is offered as part of a research program, due the persistence of some uncertainties. (#8 PATIENTS’ PERSPECTIVES: Patients consulted in this project reported facing a variety of challenges related to their amputation condition in many areas of their life. Some patients described their prosthetic socket as a burden. In terms of care and services, patients reported a good management, highlighted by the central role of prosthetists. However, some patients reported that the financial support available to amputees in Quebec varies and depends on the cause of the amputation. Patients felt that BAPs are one of the innovative health technologies that should be available in Quebec. They mentioned that they are aware of the risks and benefits of OI and therefore, the procedure cannot be suitable for all amputees. The impossibility/difficulty of fitting the prosthetic socket was the main reason that encouraged OI patients to use this procedure. In their opinion, OI provides certain benefits over prosthetic sockets and would have radically improved their life. Centralization of expertise in Montreal did not appear to be a major issue. Patients expressed more confidence in the OI team than in people in their region who may not be familiar with the technology. (#9 CONSULTED EXPERTS’ PERSPECTIVE): The experts consulted reported that BAPs can have a significant improvement of the quality of life. They also reported that the number of complications should increase proportionately as the follow-ups become longer. . In their opinion, complications should be better specified and collected in the studies, especially the number and severity of infections as well as the outcome of patients who have had an implant removed. Experts have reported that they have observed a real enthusiasm for the procedure among people living with amputations. To avoid unrealistic expectations, some experts have insisted on the need to better specify the eligibility criteria in order to better refer their patients to have the procedure. Some concerns were raised by the experts regarding the follow-up of osteo-integrated patients, mainly those living in remote areas. In their opinion, the centralization of expertise in Montreal creates inequity of access, particularly in terms of rehabilitation and follow-up. This is why they supported the importance of planning follow-up in external centres. CONCLUSION: The lower limb OI procedure has evolved significantly since the first studies in 1990. The increase in the number of publications in recent years reflects a growing interest in introducing this procedure into the care programs of patients with lower limb amputations. However, the most recent clinical studies still have many limitations, especially for longterm follow-ups of the same patient cohorts which is crucial in the context of OI. Some efficacy, safety, or quality of life data are still not well defined or specified in the studies. Consequently, there is still uncertainty about the benefit-risk balance of BAPs, the level of evidence is therefore difficult to determine. More data are needed to better identify the benefits and risks associated with OI.

Authors' recommendations: RESULTS: (#1 SOCIO-CULTURAL DIMENSION): OI is a new support option for people living with an amputation of one or two lower limbs. In Quebec, the rapid integration of highly potential innovations remains a major objective of the government. However, it is important that OI integration must be based on a rigorous assessment of its benefits and risks, as well as its impact on the sustainability of health and social services systems. (#2 POPULATIONAL DIMENSION): Diabetes and vascular disease, which are exclusion criteria for OI, are the two leading causes of lower limbs amputations (65.4% and 25.6%, respectively). Lower limb(s) amputation involves a physical and environmental reconfiguration as well as an identity reconfiguration that is noticeable daily and extends throughout life. The main option for patients to regain some level of functionality and mobility is a prosthetic socket. There are different types of prostheses, from the most basic to the most sophisticated ones. Daily use of a prosthetic socket may require numerous adjustments, revisions, and replacement of its components. Some people continue to experience problems and complications with their prosthesis and have no other options except its usage. BAPs are designed to provide a more physiological gait and posture, improve the range of motion and control, and increase osteo-perception. (#3 CLINICAL DIMENSION): Approximately 50 clinical studies evaluating BAPs have been published since the first trials in 1990. However, many of these studies have methodological concerns. For instance, the type of program or BAP used is not always specified in these studies. In addition, similar cohorts of patients seem to be used in several studies with no mention of that. Currently, it is difficult to determine the actual number of osseo-integrated patients and their long-term follow-up. A 2020 review estimated that approximately 400 patients received OPRA BAP and more than 800 received OPL BAP (the two most commonly used BAPs to date). The study assessing OPRA BAP, which has the longest follow-up available to date, reports data for only 14 patients at 15 years. For OPL, clinical studies report follow-ups of around 5 years, with a limited number of patients. (#4 RESULTS ON EFFICACY AND QUALITY OF LIFE ): In the studies, outcomes are compared to the patients' baseline status with prosthetic sockets and their observed complications. Overall, the clinical studies suggest that patients had improved functionality, range of motion, and comfort with their prosthesis regardless of the OI program used or the type of BAP received. In contrast, no significant improvement in social, mental, and emotional health was perceived by patients based on scores from questionnaires assessing their quality of life. The studies do not provide an explanation for this absence of improvement. Patients’ perspectives from clinical studies have identified the first few years after OI as a real challenge in rehabilitation and BAP appropriation. They would have to demonstrate a certain degree of determination, patience, and caution. According to these patients, even with the best care provided and sophisticated external prostheses, one must be mentally prepared to overcome the challenges that can occur after OI surgery. (#5 SAFETY): The most common complications after receiving a BAP are superficial infections at the site where the skin meets the external part of the implant and mechanical failure of the implant that requires replacement of certain components. The most serious complications are deep or bone infections, insufficient osseointegration and bone fractures. These can lead to implant removal or even re-amputation over the residual limb. With OPRA BAP, the risk of developing osteomyelitis within 10 years of surgery was 20% according to one study and the risk of this deep infection leading to implant removal was 9%. The older the placement of the BAP, the greater the risk of complications that require revision. After 10 years, the complications seem to become more frequent (particularly mechanical breakage and bone fracture). For the OPRA prosthesis, the survival rate (estimated number of implants still functional in the bone) remains high and stable for the first 5 years after surgery, then decreases to 89% at 7 years, 83% at 10 years, and finally 72% at 15 years. According to one study, the survival rate of the ILP implant is 78% at 9 years. No study has reported the survival rate of the ILP implant. Intensity and duration of BAP use, overweight, and female gender have been reported as risk factors for fractures. According to patient perspectives from the literature, the risks of falls, mechanical breakage, or infection remain daily concerns. (#6 ECONOMIC DIMENSION): According to the publication of Health Quality Ontario (HQO) on the efficiency of OI identified in the literature, which was deemed applicable to the Quebec clinical context, the implementation of a BAP is associated with an incremental cost-utility ratio of approximately $100,000 per QALY (quality-adjusted life year) compared to a prosthetic socket over a lifetime. The studied technology would be more expensive than the prosthetic socket but would be associated with additional benefits. Thus, if an analysis of the cost effectiveness of OI in patients with lower limb amputations in Quebec were to be performed, it seems reasonable to anticipate results that would be comparable to those reported in the HQO assessment report. (#7 ORGANIZATIONAL DIMENSION): Various findings and considerations from the international experience in OI have been identified in the literature and their applicability to the context in Quebec has been considered. Among these, we note the prudent selection of patients, which is an important preliminary step that can reduce certain long-term complications. As such, the eligibility criteria of the Montreal OI Clinic should allow specialists to properly refer their patients to the procedure. The potential increase in the number of patients who may require OI also raises uncertainty about the ability to provide optimal service and followup across the province. The current centralization of OI expertise in Montreal and the importance of knowledge transfer to health professionals in remote areas are factors to consider. For many countries, OI is offered as part of a research program, due the persistence of some uncertainties. (#8 PATIENTS’ PERSPECTIVES: Patients consulted in this project reported facing a variety of challenges related to their amputation condition in many areas of their life. Some patients described their prosthetic socket as a burden. In terms of care and services, patients reported a good management, highlighted by the central role of prosthetists. However, some patients reported that the financial support available to amputees in Quebec varies and depends on the cause of the amputation. Patients felt that BAPs are one of the innovative health technologies that should be available in Quebec. They mentioned that they are aware of the risks and benefits of OI and therefore, the procedure cannot be suitable for all amputees. The impossibility/difficulty of fitting the prosthetic socket was the main reason that encouraged OI patients to use this procedure. In their opinion, OI provides certain benefits over prosthetic sockets and would have radically improved their life. Centralization of expertise in Montreal did not appear to be a major issue. Patients expressed more confidence in the OI team than in people in their region who may not be familiar with the technology. (#9 CONSULTED EXPERTS’ PERSPECTIVE): The experts consulted reported that BAPs can have a significant improvement of the quality of life. They also reported that the number of complications should increase proportionately as the follow-ups become longer. . In their opinion, complications should be better specified and collected in the studies, especially the number and severity of infections as well as the outcome of patients who have had an implant removed. Experts have reported that they have observed a real enthusiasm for the procedure among people living with amputations. To avoid unrealistic expectations, some experts have insisted on the need to better specify the eligibility criteria in order to better refer their patients to have the procedure. Some concerns were raised by the experts regarding the follow-up of osteo-integrated patients, mainly those living in remote areas. In their opinion, the centralization of expertise in Montreal creates inequity of access, particularly in terms of rehabilitation and follow-up. This is why they supported the importance of planning follow-up in external centres. CONCLUSION: The lower limb OI procedure has evolved significantly since the first studies in 1990. The increase in the number of publications in recent years reflects a growing interest in introducing this procedure into the care programs of patients with lower limb amputations. However, the most recent clinical studies still have many limitations, especially for longterm follow-ups of the same patient cohorts which is crucial in the context of OI. Some efficacy, safety, or quality of life data are still not well defined or specified in the studies. Consequently, there is still uncertainty about the benefit-risk balance of BAPs, the level of evidence is therefore difficult to determine. More data are needed to better identify the benefits and risks associated with OI.

Project Status: Completed

URL for project: https://www.inesss.qc.ca/publications/repertoire-des-publications/publication/osteointegration-de-protheses-a-ancrage-osseux-chez-les-personnes-vivant-avec-une-amputation-dun-ou-des-membres-inferieurs.html

Year Published: 2023

URL for published report: https://www.inesss.qc.ca/publications/repertoire-des-publications/publication/osteointegration-de-protheses-a-ancrage-osseux-chez-les-personnes-vivant-avec-une-amputation-dun-ou-des-membres-inferieurs.html

English language abstract: An English language summary is available

Publication Type: Other

Country: Canada

Province: Quebec

Organisation Name: Institut national d'excellence en sante et en services sociaux

Contact Address: L'Institut national d'excellence en sante et en services sociaux (INESSS) , 2021, avenue Union, bureau 10.083, Montreal, Quebec, Canada, H3A 2S9;Tel: 1+514-873-2563, Fax: 1+514-873-1369

Contact Name: demande@inesss.qc.ca

Contact Email: demande@inesss.qc.ca

Copyright: L'Institut national d'excellence en sante et en services sociaux (INESSS)