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Manual Therapy 17 (2012) 39e46

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Manual Therapy

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Original article

Use of ultrasound imaging by physiotherapists: A pilot studyto survey use, skills and training

Catherine L. Pottera, Mindy C. Cairnsb,*, Maria Stokesc

aAlpine Physiotherapy, 75 Grove Road, Harpenden, Hertfordshire, AL5 1EN, UKb Post Doctoral Research Fellow, School of Health & Emergency Professions, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UKc Professor of Neuromuscular Rehabilitation, Director of Research, School of Health Professions & Rehabilitation Sciences, University of Southampton,Highfield Campus, Southampton SO17 1BJ, UK

a r t i c l e i n f o

Article history:Received 3 December 2010Received in revised form11 August 2011Accepted 30 August 2011

Keywords:PhysiotherapistsTrainingCompetencyUltrasound imaging

* Corresponding author. Tel.: þ44 1707 285 288; faE-mail address: m.cairns@herts.ac.uk (M.C. Cairns

1356-689X/$ e see front matter � 2011 Published bydoi:10.1016/j.math.2011.08.005

a b s t r a c t

Objective: This study aimed to design and pilot a questionnaire to survey the use of ultrasound imaging(USI) by physiotherapists in the United Kingdom (UK), the type and content of ultrasound trainingphysiotherapists using USI had undertaken and their perceived future training needs.Background: The use of USI by physiotherapists is becoming increasingly common but is highly operatordependent and there are safety and professional issues regarding use in physiotherapy practice.Currently there are no specific training guidelines relating to physiotherapists using USI.Methods: A questionnaire was developed, based on research literature and guidelines. Twelve experts inUSI commented on the content and design. The electronic on-line questionnaire was piloted on groupsthat were likely to be users of USI.Results: Forty-six respondents completed the questionnaire. Results indicated that USI is used predom-inantly for biofeedback and there are many unmet training needs. Respondents reported a mismatchbetween techniques for which they had received training and those that they used in practice andindicated a more structured training framework is required.Conclusions: The development and piloting of the questionnaire provides a starting point for a moreextensive evaluation of how USI is being used, the training needs of physiotherapists and benefits asa biofeedback tool. Refinement is needed and replication in a larger sample. Results could assist thedevelopment of a structured formal training framework encompassing key skills.

� 2011 Published by Elsevier Ltd.

1. Background

The use of ultrasound imagining (USI) to assess musclemorphology and guide rehabilitation decisions has developed overthe last three decades and is increasingly being integrated intophysiotherapy practice. Such imaging has been termed rehabilita-tive ultrasound imaging (Teyhen, 2007) although there is currentlyno universal consensus regarding imaging terminology. Use of USIby physiotherapists developed from medical ultrasound imaging isa recognized techniquewithin the field of musculoskeletal imaging.It is distinct from diagnostic imaging for musculoskeletal injury/pathology (Grassi and Cervini, 1998; Balint and Sturrock, 2001),which physiotherapists also use, and requires different machinespecifications, operator skills and training. For example, diagnosticimaging does not include using USI for biofeedback to train muscle

x: þ44 1707 284 977.).

Elsevier Ltd.

function and it requires higher transducer frequencies than muscleimaging, so it is important that the required scanner specificationsare understood. Current musculoskeletal diagnostic imaging cour-ses are primarily aimed at medical specialties and radiographerstherefore only partially equip physiotherapists with the skills theyrequire for the range of USI applications used in physiotherapy. AsUSI becomes more affordable (Speed and Bearcroft, 2002) andaccessible, physiotherapists are increasingly embracing this tech-nique (Henry and Westervelt, 2005; Blackledge, 2006; Oxlade,2007). In 2006, an international symposium of experts within thespecific field of USI for muscle evaluation and biofeedback reachedconsensus on the clinical and research applications of USI (Teyhen,2006, 2007). The outcome of this symposium identified current useof USI, guidance for future research (Henry and Teyhen, 2007;Stokes et al., 2007; Teyhen, 2007; Teyhen et al., 2007a, 2007b;Whittaker et al., 2007; Hides et al., 2008b) and need for adequateand appropriate training for physiotherapists (Whittaker et al.,2007; Hides et al., 2008b).

Table 1Type of work, employment status specialism and years of experience ofrespondents.

Type of work (n ¼ 38)a Responses Percentage

NHS 17 45%Private practice 19 50%Private hospitals 1 3%Private organisation 2 5%Independent Hospital 1 3%Sports team or Institute 4 11%Other 9 24%Research, University, Education, MOD, Veterinary PhysiotherapyTotal responses 53

Employment Status (n ¼ 38)a

Employed 29 76%Self-employed 14 37%Employer 2 5%Total responses 45

Scope of work (n ¼ 38)a

Neurology 1 3%Veterinary physiotherapy 1 3%Women’s health 2 5%Paediatrics 2 5%Occupational health 3 8%Other 3 8%Research 4 11%Management 4 11%Teaching and education 5 13%Sports medicine 16 42%Rehabilitation 18 47%Musculoskeletal 31 82%Total responses 90

Years of experience (n ¼ 36)

0e5 1 3%6e10 8 22%11e15 9 25%16þ 18 50%Total responses 36

a Responses to question not mutually exclusive.

C.L. Potter et al. / Manual Therapy 17 (2012) 39e4640

There are numerous professional bodies whose members useultrasound imaging within practice, with some providing guidelinesfor use (BMUS, 2007; RCR, 2011b) and standards of training (BMUS,2011; RCR, 2011a). However, none specifically relate to use byphysiotherapists and at present the governing body for physiother-apists in the UK has no published guidelines (CSP, 2011). A numbertheprofessional bodieshave formeda consortiumaiming topromotebest ultrasound practice through the accreditation of those trainingprogrammes (CASE, 2011) but few formal courses exist to trainphysiotherapists in the safe and appropriate use of USI. Modules atUniversities often focus on diagnostic ultrasound rather than forrehabilitation, and there may be a case for combining both applica-tions in USI courses for physiotherapists. Also, short, non-accreditedcourses available are often only at a basic or introductory level.

There is clearly a need for training for physiotherapists using USIbut the initial step is to investigate how it is being used. This studyaimed to design and pilot a questionnaire to survey the use of USIby physiotherapists in the UK, and identify the type and content oftraining physiotherapists using USI had undertaken and theirperceived future training needs. Questions were also asked relatingto perceived skills using ultrasound and continued professionaldevelopment (CPD) related activities.

2. Methodology

The study consisted of three phases:

1. Development of the questionnaire.2. Consultation with experts followed by revisions.3. Distribution of the questionnaire to physiotherapists.

The study focused on USI within physiotherapy practice, notdiagnostic imaging, and targeted physiotherapists who had eitherundergone training and/or were already using USI in practice.Ethical approval was gained from the University of HertfordshireFaculty of Health and Human Sciences Ethics Committee for Healthand Emergency Professions for the questionnaire development(HEPEC/12/06/11) and survey (HEPEC/05/07/43).

2.1. Development of the questionnaire

An initial questionnaire was developed based on research liter-ature and guidelines, and by categorising components of traininginto subsections (Aston-McCrimmon and Hamel, 1983; Brown et al.,2004; Frazer and Lawley, 2000; Hicks, 2005; Utwin,1995). To ensureall key skills required for using USI had been included, a panel of UKbased experts in USI in physiotherapy was identified to commentand test an initial version of the questionnaire. Experts in using USIin clinical practice and research were identified by the CharteredSociety of Physiotherapy (CSP), the UK professional body for phys-iotherapists, and authors of relevant published literature were alsoapproached. Twelve experts were identified and contacted by emailaddresses available in the public domain. They consisted of ninephysiotherapists and three qualified sonographers (one of whomwas dual qualified). One of the expert panel (MS) was involved inthe study but was not involved in data management or analysis.

2.2. Initial questionnaire (version 1)

The initial questionnaire had 27 questions, divided into fivesections: clinical use of ultrasound imaging, training, skills,continued professional development (CPD) and demographics. Thequestionnaire was sent by blind copy email. Experts were asked tochecka consentboxandrespondwithinoneweek,with commentaryon questionnaire content and design rather than completing the

questionnaire. Responses were coded by a third party. Nine validcommentaries were used to revise the questionnaire.

2.3. Revised questionnaire (Version 2)

Version 2 of the questionnaire had 38 questions and was re-sentto the same experts requesting final commentary. Experts weregiven a week to respond and eight of the nine responded.Comments informed changes to the final questionnaire to be usedfor the piloting phase. The final questionnaire had 40 questionsconsisting of single and multiple choice answers, ranked questionsusing Likert Scale and open ended questions. It was hosted by theweb based survey site SurveyMonkey (SurveyMonkey, 2007) whichprovided secure, anonymous data capture.

2.4. Survey of physiotherapists

A small scale pilot survey of Chartered Physiotherapists basedin the UK was undertaken. Non CSP members, physiotherapystudents and Chartered Physiotherapists not based in the UK wereexcluded.

Convenience sampling was used to recruit respondents whom itwas believed were likely to be using USI in practice (Sim andWright, 2000). A snowballing technique was employed to maxi-mize responses which allowed recipients to forward the invita-tional e-mail to colleagues or friends for whom they thought itwould be appropriate (Forrest, 1999). A Uniform Resource Locator(URL) to the survey was included in an invitation email. The URL

C.L. Potter et al. / Manual Therapy 17 (2012) 39e46 41

connected participants to the survey, which then asked for consent.The survey was live on-line for three weeks.

The questionnaire was sent to physiotherapists at the EnglishInstitute of Sport (EIS) and those who had purchased ultrasoundmachines via manufacturers (Pie Data, SKF Services and Mobilis),members of the Manipulation Association of Chartered Physio-therapists (MACP; a recognized clinical interest group of the CSP),physiotherapists who were members of a group with an interest inusing USI, subscribers to iCSP (the interactive website of the CSP)and prospective delegates on a USI course for physiotherapists(approved by the United Kingdom Association of Sonographers).

2.5. Data management and analysis

Data were exported into Excel for analysis and quantitative datawere presented as frequencies and percentages. Open text answerswere analysed by thematic review.

Table 2Content of formal and informal training.

Content of training Form

Background physics of ultrasonography 22Safety issues around use of the machine 22How to operate the ultrasound machine 22Ergonomics of machine and scanning 13Shown more than one ultrasound machine 18Shown more than one type of transducer 19How to enhance the quality of the image 20Research that shows reliability and validity of RUSI 15Practical experience for you to practice on other delegates 22Practical experience on patients 8How to take a CSA measurement with callipers 11Linear measurements of muscle thickness and/or width 17How to standardise measurements of muscle width and/or thickness 7Using RUSI as a biofeedback tool 20Understanding variations in muscle morphology 14Interpretation of types of muscle activity

e.g. isometric/dynamic contractions7

Ethical considerations e.g. scope& codes of practice, consent,BMUS/UKAS guidelines, storage of data

14

Other (see below)* 5*Other Formal training contentDetection of pleural effusions, diaphragmatic function,superficial thoracic lesions, pleural "gliding"DopplerCorrelation to other imaging (MRI, X-ray)

*Other Informal training contentInterpreting pathological images (not rehabilitation)Supervised imaging of peripheral joint/muscular pathologyDemonstration of US on model 8 years agoTypes of artifacts (shown by consultant radiologist)Bladder scanning

Length of training (in hours) Formal (n ¼ 23)

0e4 15e8 149e12 513e16 017e20 520+ 3Total responses 23Percentage of formal training that was practical (n ¼ 23)0e10 411e20 121e30 031e40 241e50 551e60 261e70 271e80 381e90 391e100 1Total responses 23

CSA ¼ Cross sectional area, BMUS ¼ British Medical Ultrasound Society, UKAS ¼ United

3. Results

3.1. Response

Forty-six valid responses were received with some respondentsreportinghavingundertakenboth formal and informal training,whichis normal for CPD activities. Not all respondents completed all ques-tions; therefore results are presented as valid responses anda percentage out of those who completed the item e.g. 23/44 (52%).Somequestions allowed respondents to choosemore thanone answerand where this is the case, no percentage is presented in the text.

The exact response rate could not be established due to the useof ‘snow-balling’ technique of recruitment. A rough estimatesuggests that the URL could have potentially been e-mailed toapproximately 1200 physiotherapists, giving a low response rate.However, it is not known how many of the sample receiving thesurvey did not complete it because they were not trained or using

al (n ¼ 23) Informal (n ¼ 29) Formal % Informal %

8 96 289 96 31

22 96 767 57 248 78 28

13 83 4518 87 625 65 17

17 96 5913 35 453 48 10

11 74 385 30 17

12 87 419 61 316 30 21

4 60 14

5 21 17

Informal (n ¼ 29) Formal % Informal %

17 4% 60%3 61% 10%3 22% 10%1 0% 3%3 0% 10%2 13% 7%

29

17%4%0%9%

22%9%9%

13%13%4%

Kingdom Association of Sonographers, MRI ¼ Magnetic Resonance Imaging.

Fig. 1. Percentage of respondents trained to image specific muscles between formal, informal and future training needs.

C.L. Potter et al. / Manual Therapy 17 (2012) 39e4642

USI. The type of work, employment status, scope of work orspecialism and years of experience are shown in Table 1.

3.2. Training received in use of ultrasound imaging

Out of the 44 respondents answering the question regardingtraining, just over half, 23/44 (52%) had received formal training inusingUSI but 21/44 (48%) hadreceivedno formal training. The contentof the formal training and informal training is shown in Table 2. Morecomponents were offered during formal training than informal, otherthan ‘practical experience on patients’. The biggest discrepancybetween the two types of training was in the area of backgroundphysics and safety of ultrasonography, with 96% reporting this topicbeing included in formal training and only 28% in informal training.

Fig. 2. Respondents perceived comp

The muscle groups respondents reported having been taught toimage during both formal and informal training, and those theyidentified as a future training need, are shown in Fig.1. The informaland formal training offered imaging of similar muscle groups withabdominal imaging representing the greatest percentage oftraining with none or little training offered during informal trainingfor the cervical spine musculature and bladder.

3.3. Skills

Respondents were asked to rate their perceived level ofcompetence from a list of skills (Fig. 2). They were also asked to ratetheir level of priority for future training for the same set of skills(Fig. 3). Results indicated that interpreting muscle morphology and

etency of specific skills, n ¼ 40.

Fig. 3. Respondents rating of priorities for future training, n ¼ 40.

C.L. Potter et al. / Manual Therapy 17 (2012) 39e46 43

gaining information about muscle activity were the competenciesthat respondents felt least competent but were also rated as highpriorities for future training.

3.4. Clinical use of ultrasound imaging and continued professionaldevelopment (CPD)

Despite having received either formal or informal training in theuse of USI, 23/43 (53%) respondents reported not using USI inpractice. The main reasons stated for not using USI were lack ofavailability of an ultrasound machine and not feeling competent touse USI. Of the 20/43 (47%) of respondents who were using USI inpractice a wide range of uses were reported and these and theamount of time spent using USI are shown in Table 3. The sectionexamining CPD began with a question regarding attitudes to fourstatements about CPD and is summarized in Table 3 along witha summary of time spent on USI CPD activities. The majority ofrespondents, 22/32 (69%), reported undertaking between 0 and 2 hper month of CPD with scientific journals, the internet, otherprofessionals and clinical interest groups being the main sources ofCPD support (27%, 24%, 21%, 16% respectively).

4. Discussion

The majority of respondents were working in areas such asmusculoskeletal (82%), rehabilitation (47%) and sports medicine(42%). However, this profile suggests some bias of the sampling ofgroups such asMACP and EIS which specialise in these areas. There isliterature about theuseofUSI in thefieldofwomen’shealth (Critchley,2000; Teyhen, 2006; Peng et al., 2007) but very few respondentsworked in this field. If the women’s health special interest group andother groups such as veterinary, paediatric, and neurology had beentargeted, the responses are likely to have been different.

All skills/elements were represented in both the formal andinformal training; howevermore training on background physics ofthe machine and safety issues was received during formal trainingcompared to informal training. This difference may be due to a lackof time, with 60% of informal training being only 0e4 h durationcompared to 61% of formal training being 5e8 h. However informal

training may be insufficient to provide respondents with thenecessary skills outlined by the British Medical Ultrasound Society(BMUS), in particular calculating the lowest output levels that stillachieve a clear image (Hides et al., 1998;Whittaker et al., 2007). TheRoyal College of Radiologists in their recommendations for ultra-sound training for medical and surgical specialists stress the needfor both theoretical and practical elements to be included intraining and advise different levels of training and the type andlevel of supervision (RCR, 2011b). Although covering a wider scopethan USI which physiotherapists use, this may be a useful model toconsider for physiotherapists training to use ultrasound imaging.

The majority of respondents reported that imaging of theabdominal muscles was undertaken in both formal and informaltraining. This may reflect the increasing interest in motor controlretraining and also the validity and reliability (Wallwork et al.,2007; Vasseljen et al., 2009) and utility of abdominal imaging(Critchley, 2000; Ferreira et al., 2004). It may also be that theabdominal muscles are relatively easier to image and interpret thansome other muscle groups. Imaging of the lower limb and thebladder showed the large discrepancies between the two types oftraining; however this may have been influenced by the samplingstrategy. Similarly training to image lumbar multifidus showedquite large discrepancies. This finding is of interest as there isconvincing evidence of differential functioning (Moseley et al.,2002) and atrophy (Hides et al., 1994, 1995b, 1996, 2008a) anda reduced ability to voluntarily contract multifidus in chronic lowback pain patients (Wallwork et al., 2009) possibly suggesting thatthe ability to image this muscle effectively may be of use clinically.Little training was reported for cervical musculature; however, thiswas identified as a future training need by many respondentsdespite its use being less well evidenced than for the abdominal ormultifidus muscles (Javanshir et al., 2010).

Safety issues, biofeedback and recognition of muscle borders toidentify CSA were the three skills at which most respondentsperceived themselves as being ‘competent’. Most respondentsrated themselves as ‘not at all competent’ for use of callipers tomeasure CSA; linearmusclemeasurements; gaining information onmuscle activity and interpreting muscle morphology. This may beexplained by the relatively short duration of training that many

Table 3Reported use of RUSI and continuing professional development.

Use of RUSI (n ¼ 21)a Responses Percentage

Research 4 19%Training other physiotherapists 6 29%Measuring cross sectional area (CSA) of muscle in the clinical setting 6 29%Measuring linear muscle measurements of thickness and/or width 7 33%Evaluating muscle morphology e.g. shape, pennation angle, muscle fascicle length 4 19%Monitoring outcome of treatment 8 38%Biofeedback tool 17 81%Assess soft tissue trauma and monitor healing 8 38%Other 5 24%Total responses 65

Hours per month using RUSI (n ¼ 21)1e5 11 52%6e10 3 14%11e15 4 19%16e20 1 5%21e25 0 0%26e30 0 0%31þ 2 10%Total responses 21

Reasons for not using RUSI (n ¼ 24)a

No training available 6 25%Lack of training to feel competent 9 38%No machine on site 15 63%Machine on site but not available for use 2 8%Machine available but different from that used in training 0 0%Lack of support for the service from management 4 17%Patients not suitable for RUSI e.g. unable to interpret the image for biofeedback 0 0%Patients unable to comply with instructions 0 0%Lack of supervision 2 8%Lack of confidence 2 8%Other 8 33%Total responses 48

Hours per month of CPD related to RUSI (n ¼ 32)0 10 31%1 4 13%2 8 25%3 2 6%4 1 3%6 2 6%8 1 3%10 2 6%Total responses 32

Agreement with CPD statements Disagreestrongly

Disagree Neither agreenot disagree

Agree Agreestrongly

Totalreponses

There are enough opportunities for formal learning to maintain my skills in UI 4 13 14 4 2 37I have the resources to receive informal supervision for CPD in UI 8 14 5 9 1 37I have read literature about RUSI 1 5 19 10 38I review patients with other practitioners with skills in UI 14 8 5 8 2 37

a Respondents were able to choose more than one category.

C.L. Potter et al. / Manual Therapy 17 (2012) 39e4644

respondents reported receiving. It is of note that althoughmeasuring CSA has been validated against other measurementtools (McMeekin et al., 2004; Reeves et al., 2004; Sipila andSuominen, 1993), and as such can be considered evidence based,it was not rated particularly highly as a future training need.

Many respondents indicated that they had inadequate opportu-nities for formal learning to maintain their skills. The reason may bea combination of paucity of appropriate training courses, and alsolimited funding and time to attend training courses. Similarly themajority of respondents indicated that there were inadequateresources to receive informal supervision to maintain CPD; possiblyindicating a lack of appropriately qualified and skilled mentors. Thisfinding is in keeping with the finding that the majority of respon-dents reported maintaining their CPD through independent theo-retical learning e.g. reading USI literature, scientific journals and theuse of the internet despite USI being a practical skill and highlyoperator dependent tool (Hides et al., 1995a; Whittaker et al., 2007).

The majority of respondents used USI for biofeedback yet it isnot known if ultrasound biofeedback influences treatment outcome(Hodges, 2005; Teyhen, 2006). However as other forms ofbiofeedback have been shown to improve outcome (Kim andKramer, 1997) this may be a useful area for future research forultrasound imaging (Henry and Teyhen, 2007; Whittaker et al.,2007). A common theme that emerged from the open questionswas that USI is very operator dependent (Balint and Sturrock, 2001;Goldberg and Pettersson, 1996; Grassi and Cervini, 1998; Whittakeret al., 2007) and this was perceived as a ‘pitfall’ andmay support theneed for structured and on-going training.

4.1. Limitations & future work

4.1.1. QuestionnaireThe questionnaire was developed based on current guidance

and consensus from an expert panel. Perceived expertise is

C.L. Potter et al. / Manual Therapy 17 (2012) 39e46 45

subjective and credentials to qualify as an expert are unknown,therefore the competency of the panel may not have beenexhaustive.

The questionnaire consisted of 40 questions. However, there isevidence that the attention span of some respondents may waneafter 25e30 questions (Forrest, 1999). Many questions allowedmultiple answers, thereforewere notmutually exclusive; this madeinterpretation of the results more difficult and should be addressedin future work. Not all questions were compulsory fields; thereforenot all questions were completed by all respondents resulting invarying response for many questions. This should also be addressedin future studies.

4.1.2. SamplingBias may have existed in sampling, as using the Internet relies

upon users having Internet access. Although earlier studies claimthat Internet questionnaires are not representative of the generalpopulation (Best et al., 2001; Hewson et al., 2003), more recentstudies support the reliability, validity and generalizability ofcomputer based internet surveys (Howell et al., 2010; Tolstikovaand Chartier, 2009). Similarly it is acknowledged that the samplewas small and may not necessarily represent all aspects of USI useby physiotherapists in the UK. A decision was made to use conve-nience sampling targeting groups of physiotherapists which theresearch team believed were likely to be using USI in practice.Whilst this was a pragmatic decision in this pilot stage, futuresurveys should use a broader sampling strategy which would alsoallow an estimation of the prevalence of use of USI byphysiotherapists.

5. Conclusions

The primary reported use of USI in this small scale pilot studywas for patient and therapist biofeedback. This application has notbeen shown to have a positive or negative effect on treatmentoutcome and therefore further research in this area is indicated.The majority of respondents worked in the musculoskeletal sector;however bias in the sampling strategy and the pilot nature of thisstudy may have influenced these results.

Clear discrepancies between the components offered in formaland informal training were reported, specifically regarding tech-nical and background physics. Since there are safety issues associ-ated with using USI and interpretation of the images are operatordependant (vanHolsbeeck, 2004; Whittaker et al., 2007), the lowlevel of training reported is of concern and suggests a need for moreformal training.

Formal training courses specifically designed for physiothera-pists remain relatively few and the development of a structuredframework for USI training for physiotherapists similar to those forother professions is needed.

Acknowledgements

The authors thank the employer of the PI (CP) at the time of datacollection, Bupa.

Thanks also go to the expert panel, who all agreed to be namedin this section: Paul Carnell, Katy Cook, Stephen Cipriani, YvonneColdron, Duncan Critchley, Jane Dixon, Robert Laus, John Leddy,Christine Mallion, Gabrielle Rankin, Jonathan Thompson. Sadly,Christine Mallion has passed away since contributing to thedevelopment of this questionnaire.

The authors are also grateful to all the groups throughwhom thepilot questionnaire was initially distributed.

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