ICEROSS - a consensus view: a questionnaire survey of the use of ICEROSS in the United Kingdom
I. McCurdie *
R. Hanspal *
The management of the individual with a trans-tibial amputation has been strongly influenced by the increasing use of the ICEROSS socket system over recent years. Despite this growth in clinical experience, there has been very little research into its place in current prosthetic practice, and prescribing activity is largely determined by personal experience. In order to formulate the current consensus view on the use of ICEROSS, questionnaires were sent to 42 doctors and 43 senior prosthetists around the UK. The influence of 38 different factors on prescribing activity was assessed using a grading system (ranging from "primary indication" to "absolute contraindication"). An 85% response rate was achieved and no significant differences in response between the two professional groups were identified. Those factors considered by most to be positive indications for using ICEROSS were "pistoning", "shear-sensitive skin / split-skin grafts", "patient unsuccessful with supracondylar (s/c) or cuff suspension" and "insufficient suspension due to change in type or level of activity". Those considered by most to be absolute contra-indications were "ulceration / unhealed scars", "poor patient hygiene" and "poor patient commitment to prosthetic rehabilitation". This consensus of opinion is in keeping with the results of the few published audits of ICEROSS usage. There was a lack of consensus, however, about the use of ICEROSS in some situations, including skin complications.
Whilst some consensus does exist about the use of ICEROSS, the results of this survey indicate significant variations in clinical practice which serve to illustrate the urgent need for data from prospective clinical trials.
The Icelandic Roll-on-Silicone Socket (ICEROSS) was first developed in 1985 by Ossur Kristinsson as a system which relies on the unique properties of silicone and claims to considerably improve the weight-bearing capability of the prosthesis and the interface between prosthesis and user (Kristinsson, 1993). The system has been used increasingly in the United Kingdom over the past five years, but despite this, there has been very little research into its place in current prosthetic practice. The only published works have been retrospective audits of clinical practice (Cluitmans et al., 1994; Panagamuwa et al., 1995) which both identified a significant incidence of troublesome side effects, as well as certain advantages over a conventional socket system. Panagamuwa et al. (1996) concluded that careful patient selection was necessary to improve the effectiveness and minimise the complications of the ICEROSS system.
Prescribing activity is usually determined by a combination of several factors. These include evidence from clinical research (eg. drug trials), personal experience, audits of current practice, and anecdote. The variation seen in prescribing activity is a result of the differing influence of these factors among individual clinicians. With regard to ICEROSS, current patient management is based largely on clinical experience and anecdotal evidence, rather than any sound research data. In the absence of prospective trial data, therefore, the increasing breadth of clinical experience in the use of ICEROSS represents a significant influence on prescribing activity. The aim of this study was to formulate a consensus view on the use of ICEROSS in clinical practice by collating the opinions of those with experience in using this system.
A questionnaire was sent to 42 doctors and 43 senior prosthetists known to have experience with the ICEROSS system and working in 38 different centres around the UK. The questionnaire detailed 38 factors which might be considered when prescribing for individuals with a trans-tibial amputation (Table 1). A grading system was described, ranging from "an absolute / primary indication" (grade A) to "an absolute contra-indication" (grade E) (Table 2). Practitioners were asked to give each factor a grade to indicate whether they considered ICEROSS to be the best treatment option (grade A), the worst (grade E), or somewhere in between for that particular factor. Comments on any other factors influencing prescribing activity were invited.
Completed questionnaires were returned by 37 (88%) of the doctors and 35 (81%) of the prosthetists, giving an overall response rate of 85%. This represents an unusually high response rate for a postal questionnaire. The actual numbers of responses given by doctors and prosthetists for each factor are shown in Table 1. Where the total number of responses to any question does not equal 72, this indicates that one or more respondents failed to answer this question. There were no significant differences in the pattern of responses between the two groups. Doctors gave, on average, 2.5 A grades (range 0-10) and prosthetists 3.3 A grades (range 0-12). The average number of E grades (ie absolute contra-indications to using ICEROSS) was 5.4 (0-15) and 3.0 (0-13) respectively.
The grades given to certain factors showed a definite polarity, with the majority of respondents considering them to be positive indications or absolute contra-indications. Whilst no factor had a mode of grade "A" (ie more respondents considering ICEROSS to be the treatment of choice than any other grade), four factors were found to have a distribution whose mean grading which lay between A and B. These are shown in Table 3, along with the three factors with a mode of grade E. The closeness of the range of grades given to these factors indicates the degree of consensus that exists among prescribers (Table 1).
Some factors were not graded as "A" by any respondents (Table 4), indicating that none of the prescribers considered these factors to be an absolute reason for using the ICEROSS system. Those factors with a mode of grade "C" represent circumstances in which more prescribers are neither swayed towards, nor against, the use of ICEROSS, ie more select grade C than select any other grade (Table 4). Some factors were given both "A" and "E" grades by more than 4 respondents, suggesting that opinions vary widely on the use of ICEROSS in these circumstances, and that some considered these factors to be primary indications, whilst others thought them to be absolute contra-indications to the use of ICEROSS (Table 4).
All clinicians should ensure that any therapeutic intervention used, whether it be a drug, a course of physiotherapy, or a prosthesis, is both safe and effective. This can only be achieved by understanding the indications, contra-indications, potential side effects, and interactions of the proposed treatment. With such knowledge, gained from a combination of formal research and clinical experience, the safety and effectiveness of the treatment can be maximised. In the absence of prospective trial data on the outcome of ICEROSS prescription to individuals with a trans-tibial amputation, this study has sought to establish the current consensus of opinion among a large number of clinicians in the UK.
The high response rate to the questionnaire indicates the level of interest among clinicians in this complex area of prosthetic practice, and perhaps an eagerness to improve the understanding of the use of the ICEROSS system. The results show that some consensus does exist in certain clinical situations and patient types, with strong agreement on a few indications and absolute contra-indications (Table 3). However, there were no individual factors or circumstances in which the majority considered ICEROSS to be the treatment of choice. Overall, the findings are consistent with those of the previously published audits. Poor patient commitment to prosthetic rehabilitation was recommended as a contra-indication by Panagamuwa et al. (1995) and so was included in the questionnaire - it was graded "D" or "E" by 89% of respondents. The observation by Cluitmans et al. (1994) that suspension was the most significant advantage of ICEROSS was also apparent from the responses in this study.
Several factors were universally considered not to be primary indications (see Table 4, - no "A" grades), although not necessarily contra-indicating the use of ICEROSS. A number of factors were found to have a mode of grade "C" (Table 4), indicating perhaps that a substantial number of prescribors would consider an ICEROSS prosthesis to be suitable, but of no particular benefit compared to other systems. This may indicate a genuine belief that there is no significant difference in outcome between conventional socket and an ICEROSS socket in these circumstances. It may, however, reflect a lack of sufficiently clear evidence to influence prescribing activity in these patients, such as the diabetic or traumatic amputee. A recent audit of ICEROSS use in the authors' unit identified patients with peripheral vascular disease to be significantly more likely to discontinue its use than other disease groups (unpublished data).
Any degree of consensus appears to be lost when one looks at those factors which were given a grade of "A" or "E" by an arbitrarily chosen number of respondents (see Table 4, which lists factors given an "A" or "E" grade by at least four (6%) of respondents). It is interesting to note the number of skin-related factors in this list. Some clinicians, both doctors and prosthetists, clearly have diametrically opposed views on whether ICEROSS should be used in these circumstances. Again, such views are likely to be a reflection of personal experience, rather than evidenced-based practice. It is the outcome of using ICEROSS in these clinical situations (whether it be favourable or otherwise) that deserves closer attention through clinical study, in order to guide prescribing activity with more confidence.
A wide variety of comments were made by respondents about their experiences with ICEROSS. Several raised the issue of cost and its restrictive influence on prescribing. Whilst it is acknowledged that cost is a significant factor, it was not included in the questionnaire as it was felt that it exerted an equal influence on prescription for all patients within any one centre. Many respondents commented on the complexity of the assessment required when prescribing ICEROSS, and the frequency with which skin problems were encountered.
The use of ICEROSS and other silicone-based prosthetic systems is likely to continue to increase in the future. As clinicians are increasingly required to adopt an evidence-based approach to their clinical practice, there is an urgent need for controlled, prospective, clinical trials in this field.
- Cluitmans J, Geboers M, Deckers J, Rings F, (1994). Experiences with respect to ICEROSS system for trans-tibial prostheses. Prosthet Orthot Int 18, 78-83.
- Kristinsson O (1993). The ICEROSS concept: a discussion of philosophies. Prosthet Orthot Int 17, 49-55.
- Panagamuwa B, Altay O, Lindsay J, et al. ( 1994). An audit of ICEROSS usage. In: Proceedings of the Annual Scientific Meeting, International Society for Prosthetics and Orthotics, UK National Member Society, p28-30.