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Assessment and Diagnosis of Knee Injuries
Professional articles
417 Key Words Extended scope, clinical diagnosis, knee injuries, arthroscopy, orthopaedic outpatient clinics.
Assessment and Diagnosis of Knee Injuries
by Victoria Dickens Fazal Ali Helen Gent A Rees
The value of an experienced physiotherapist
Summary A range of titles now reflects emerging roles in physiotherapy: clinical specialists, extended scope practitioners, and more recently consultant therapists. While each role is essentially different, what people in these roles have in common is experience. There is a move to cut down patient waiting times both for operations and for orthopaedic consultant outpatient appointments. An experienced physiotherapist with additional skills would help achieve a reduction in patient waiting times, being able to triage patients for either conservative treatment or a consultant appointment. This study investigates physiotherapists’ diagnostic accuracy of acute knee injuries and answers the question: ‘Can a physiotherapist manage the diagnosis of patients presenting with an acute knee injury safely and effectively?’ This is a prospective study investigating the agreement between physiotherapists’ clinical diagnoses and arthroscopic diagnosis of the knee. Fifty consecutive new patients referred to one consultant’s acute knee clinic were recruited into the study. Assessment was by a consultant knee surgeon and two experienced physiotherapists in random order. An initial diagnosis was then made. This was compared to final diagnosis, which was mainly based on arthroscopic findings and special investigations. The results show that experienced physiotherapists are able to diagnose acute knee injuries with a high rate of accuracy, sensitivity and specificity.
Dickens, V, Ali, F, Gent, H and Rees, A (2003). ‘Assessment and diagnosis of knee injuries: The value of an experienced physiotherapist’, Physiotherapy, 89, 7, 417-422.
Introduction Physiotherapists are highly experienced in the management of musculoskeletal conditions. Weale and Bannister (1995) found that an experienced physiotherapist who has received additional training is as capable of managing selected orthopaedic outpatients as staff grade orthopaedic surgeons, and can offer an effective ser vice safely in outpatient clinics. Many hospitals currently use senior house officers in outpatient clinics who do not have as much experience as experienced physiotherapists in the management of musculoskeletal cond-
itions. Furthermore, up to half of orthopaedic outpatients are seen by sub-consultant grades (Kiff and Sykes, 1988). Many orthopaedic outpatient waiting lists are long, with the majority of referrals for conditions that do not respond to surgical intervention (Weale and Bannister, 1995). Many of these patients can be best managed by experienced physiotherapists (Hockin and Bannister, 1994. This study examines the ability of experienced physiotherapists both to make a correct diagnosis and to recognise when a patient requires an arthroscopy. The first recorded use of a specially trained physiotherapist as a ‘first line filter system’ for orthopaedic patients not obviously requiring surgical intervention was in Exeter Health Authority in 1986 (Byles and Ling, 1989). Since then, the numbers working in this extended role have rapidly increased. The initial growth in these posts has been linked to efforts to halt the rise in hospital waiting lists, reduce costs and lower junior doctors’ hours of work (Durrell, 1996; DakerWhite et al, 1999). Gardiner and Turner (2002) performed a retrospective audit comparing clinical diagnosis of physiotherapists working in an extended role and orthopaedic surgeons with the results of arthroscopies. This study showed favourable results for physiotherapists working in this role. Physiotherapists are specifically trained in the management of musculoskeletal conditions that do not respond to surgical intervention. Arthroscopic examination of the knee is not a substitute for careful clinical assessment. Noble (1992) discussed several aspects of the uses and misuses of arthroscopy. He questioned: ‘How many arthroscopies are clinically essential preoperatively, and have been beneficial to the patient post-operatively?' The current medical environment requires physicians Physiotherapy July 2003/vol 89/no 7
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to be critical of the tests that are used (Lawson and Nutton, 1995. Each test should ideally be low cost and provide information that will help with future decisions on how to proceed, with either arthroscopic surgery or non-operative treatment. So if the clinical examination and diagnosis are correct, it is the most cost-effective non-invasive method of diagnosis available. Methodology Fifty consecutive new patients who attended one consultant’s outpatient knee clinic, over a period of ten weeks, were recruited into the study. Patients were excluded if they had any of the following: ■ ■ ■ ■
A confirmed fracture Previous knee surgery Severe osteo-arthritis Referral from another consultant
All recruited subjects were given an information sheet and asked to sign a consent form. It was made clear to all participants that their treatment would not be influenced by inclusion in this study and they all took part on a voluntary basis. Subjects who agreed and consented to take part in the study underwent a clinical assessment by three clinicians (the consultant and two physiotherapists, identified in this study as 1 and 2) in a balanced presentation order. Clinical Assessment All three clinicians were asked to perform a standard assessment that was normal for their working practice. The assessment comprised two sections: Subjective examination An interview including history of the problem, mechanism of injury, previous knee injuries or problems, site, type and behaviour of pain. Objective examination Including observation, ligament testing, meniscal testing, accessory movements of both tibio-femoral and patello-femoral joints and palpation. All the assessments were performed within a similar time limit (five to ten minutes), in a systematic manner and with comparison to the unaffected knee. After the assessment each clinician made an independent diagnosis. Each of the three Physiotherapy July 2003/vol 89/no 7
clinicians’ diagnoses and their decisions between conser vative and operative management were blindly recorded on separate forms. Although each clinician made a decision on the subjects’ management the final decision rested with the orthopaedic consultant. Any patients who were not referred for an arthroscopy were referred for physiotherapy and reviewed six to eight weeks later by the orthopaedic consultant. For the purpose of this study, and although there are limitations to this method, if these patients improved with conservative treatment and did not undergo an arthroscopy the consultant’s diagnosis was deemed to be correct, even when disagreement in diagnoses occurred. All arthroscopies were performed by, or under the supervision of, the same consultant who was an experienced arthroscopist. The clinical diagnoses were then compared to the diagnosis made at arthroscopy and the data were analysed. Each lesion was analysed to determine the sensitivity, specificity and accuracy of the diagnosis. The following definitions were used to calculate the percentages of patients with or without each lesion. Using a medial meniscal tear as an example: ■ A true positive is when a medial meniscal tear is suspected and then confirmed at arthroscopy. ■ A true negative is when examination has not indicated a tear and none is found at arthroscopy. ■ A false positive is when a tear is suspected, but not found. ■ A false negative is when a tear is not suspected but one is found. Sensitivity The sensitivity of a diagnostic test reflects the ability of the test to diagnose correctly a lesion which is present (true positive). The greater the sensitivity of the test, the more likely it will detect the lesion. Specificity Specificity reflects the ability of the test to determine correctly that a lesion is not present (true negative). The greater the specificity the more likely it is that patients who do not have a lesion will be excluded by the test.
Research report
Accuracy Accuracy is defined as the ability to detect correctly all cases who do have a particular lesion (true positive) and those who do not (true negative) in a set population. Results Characteristics of Subjects The final sample comprised 50 patients, 36 men and 14 women. There was no age limit for this study and patients recruited were aged between 16 and 64 years. Results of Clinical Diagnosis Of the 50 patients, 33 had an arthroscopy and 17 had conservative management. Conservative Treatment A total of 17 patients had conservative treatment after assessment. Table 1 shows the diagnoses for these patients and highlights the disagreements in diagnosis between clinicians. All these patients improved. The consultant’s diagnosis was the one on which treatments were based. Arthroscopy A total of 33 patients had an arthroscopy following assessment. Table 2 shows their confirmed diagnosis (single and multiple lesions). It illustrates the patients who had multiple lesions within their knees. The incidence of meniscal injuries associated with anterior cruciate ligament tears was high, five of the 13 knees with anterior cruciate ligament injuries had meniscal tears; three had medial meniscal tears and two had lateral meniscal tears. Similarly the three patients with patello-femoral pain syndrome who were chosen to have an arthroscopy did so as a plica was also suspected; this was confirmed, and dealt with at arthroscopy. Analysis of Results Table 3 shows the sensitivity, specificity and accuracy of the diagnosis made by each clinician with respect to the most common injuries found (medial meniscus, lateral meniscus, anterior cruciate ligament and patello-femoral pain syndrome). The correct initial diagnosis in this study was made by the consultant in 92% of cases, by physiotherapist 1 in 84% of cases and by physiotherapist 2 in 80% of cases.
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Table 1: Diagnoses for all patients who had conservative management (n = 17) Level of agreement
Conservative diagnosis
Numbers of subjects
All three clinicians in agreement
Patello-femoral pain syndrome Osteo-arthritis Other (pre-patellar bursitis)
10 2 1
Disagreement between two or more clinicians
Patello-femoral pain syndrome versus lateral meniscal tear Patello-femoral pain syndrome versus medial meniscal tear Osteo-arthritis versus lateral meniscal tear Osteo-arthritis versus loose body
1 1 1 1
Table 2: Patients who had an arthroscopy and their confirmed diagnosis (single and multiple lesions) (n = 33) Type of lesion
Arthroscopy diagnosis
Number of subjects
Single
Anterior cruciate ligament Medial collateral ligament Medial meniscus Lateral meniscus Osteo-arthritis Loose body
8 1 7 4 2 1
Multiple
Anterior cruciate ligament + medial meniscus Anterior cruciate ligament + lateral meniscus Anterior cruciate ligament + medial collateral ligament Patello-femoral pain syndrome + plica Posterior cruciate ligament + medial collateral ligament
3 2 1 3 1
Table 3: Sensitivity, with percentage (95% ‘exact’ confidence interval), specificity and accuracy of each clinician’s diagnosis of the most common injuries – medial meniscus, lateral meniscus, anterior cruciate ligament and patello-femoral pain syndrome Clinician
Sensitivity (%)
Specificity (%)
Accuracy (%)
Anterior cruciate ligament Consultant Physiotherapist 1 Physiotherapist 2
100 (77-100) 93 (66-100) 69 (52-92)
100 97 98
100 98 94
63 (44-97) 63 (44-97) 44 (26-88)
98 98 98
96 94 96
40 (7-93) 40 (7-93) 40 (7-93)
100 98 98
98 96 96
100 92 92
100 98 98
Medial meniscus Consultant Physiotherapist 1 Physiotherapist 2 Lateral meniscus Consultant Physiotherapist 1 Physiotherapist 2
Patello-femoral pain syndrome Consultant Physiotherapist 1 Physiotherapist 2
100 (75-100) 92 (64-99) 92 (64-99)
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Discussion The purpose of this study was to investigate the question: ‘Can experienced physiotherapists manage the diagnosis of patients presenting with knee injuries safely and effectively?’ It also looks into whether or not an experienced physiotherapist can fulfil the role of an orthopaedic consultant’s assistant in outpatient clinics. Terry et al (1995) concluded that a thorough clinical assessment could provide enough information to make a definitive pre-operative diagnosis. They investigated 206 patients (216 knees) and were correct with the primary preoperative clinical diagnosis in 175 knees (81%), with an overall accuracy of 93%. Oberlander et al (1993) also found that clinical examination of the knee had an accuracy of 93%. O’Shea et al (1996) looked prospectively at 156 knees and concluded that the overall assessment of knees was accurate in 89% of cases. Bollen and Scott (1996) retrospectively investigated an apparent poor accuracy of diagnosis by referring doctors for patients with anterior cruciate ligament ruptures. He reported that the original physician had made the correct diagnosis in only 9.8% of cases. This highlights the need for patients to be assessed by an experienced clinician (doctor or physiotherapist) with a special interest in knee injuries. We have shown that experienced physiotherapists have an excellent rate of diagnostic accuracy with respect to anterior cruciate ligament injuries. In this study anterior cruciate ligament tears were diagnosed with an accuracy of 98% by physiotherapist 1 and 94% by physiotherapist 2. Previous studies report between 67% and 99% accuracy (O’Shea et al, 1996; Oberlander et al, 1993; Simonsen et al, 1984). In 39 knees that had arthroscopic examination, we found ten medial meniscal tears and six lateral meniscal tears. Lateral meniscal tears were difficult to diagnose especially when associated with anterior cruciate ligament tears. The sensitivity of diagnosing an isolated lateral meniscal tear by all three clinicians was only 40%. These results are comparable with many previous studies on the clinical accuracy of diagnosing meniscal lesions (Oberlander et al, 1993; O’Shea et al, Physiotherapy July 2003/vol 89/no 7
1996). They are also comparable with the reported accuracy of magnetic resonance imaging (Weinstabl et al, 1997; Lui et al, 1995; Miller, 1996). In this study only four patients presented with isolated lateral meniscal tears. Due to this low number, if one of these patients were diagnosed incorrectly it had a large effect on the results. It is generally agreed that anterior knee pain and patello-femoral problems should be managed conservatively with physiotherapy. Post and Fulkerson (1994) state that accurate questioning and clinical examination are essential for correct diagnosis of these problems. An arthroscopy is not necessary to diagnose patellofemoral problems and can sometimes be inconclusive, so that a patient may undergo an operative procedure for nothing. In this study all 15 patients diagnosed on presentation with patello-femoral pain syndrome proceeded to have a favourable outcome with the chosen management. No firm conclusions should be made about the accuracy of diagnosis of lesions in the smallest groups, eg loose bodies and osteo-arthritis, which each included only one patient It should also be noted that the specificity of the test results may be overestimated (true negatives) because it is not possible to know whether those who did not receive an arthroscopy had a lesion. If after clinical examination and diagnosis, arthroscopy was not the chosen treatment, the most common intervention was physiotherapy. Seventeen patients presenting with a knee injury in this study did not receive an arthroscopy. All of these patients had a course of physiotherapy and symptoms had improved when reassessed by the consultant six weeks later. Not all physiotherapists are experts. The physiotherapists in this study were experienced in the field of orthopaedics and had a special interest in knee injuries, with an average of five years’ clinical experience as a senior physiotherapist working in orthopaedics. Although musculoskeletal assessment forms a substantial part of physiotherapy undergraduate and orthopaedic postgraduate education, physiotherapy specialists should aim to per form this type of assessment in the same way as a surgeon,
Research report
ie diagnosing to ensure those patients who need further investigations get them. A physiotherapist working in an extended role needs to be able to adapt accordingly. Good communication is essential to the success of these projects. This includes consultant and general practitioner support, open access to medical advice, including an immediate opinion if necessary, and cross-referral. It is recognised that this was a small sample and because there were a number of different categories of diagnosis it meant that there were very small numbers of subjects in some categories, for example lateral meniscal tears. This could have had an effect on the results and made comparison to results of other studies limited. The results of this study and previous literature show that diagnosis of lateral meniscal tears is more difficult than other lesions. The clinical tests for diagnosis of lateral meniscal tears should be revisited to try and find a test which is more sensitive. Additionally, only two physiotherapists took part in this study. It is recommended that this study should
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be repeated on a larger scale with more patients and more clinicians. Multiple lesions commonly occur following injury, but the problem of diagnosing them, apart from meniscal and anterior cruciate ligament tears, has not been widely reported. Further research should be completed to consider the accuracy of clinical assessment when there is more than one lesion inside the knee. This study looking at physiotherapy assessment skills did not look into the accuracy of diagnosis of multiple lesions, which could be investigated further at a later date. However, looking at things simply a physiotherapist, working in this capacity, needs to be able to decide whether a patient needs an arthroscopy or not. This study has shown that an experienced physiotherapist is able to do this in most cases by accurately diagnosing the main lesion. The use of experienced physiotherapists as orthopaedic assistants in outpatient clinics may be a realistic and effective solution to the problems created by long waiting lists and junior medical staff in clinics.
Authors Victoria Dickens MSc MCSP was a senior physiotherapist at Rotherham District General Hospital and is now a clinical specialist at Hope Hospital, Salford. Helen Gent BSc MCSP is a senior physiotherapist and Miss A Rees FRCS is a consultant orthopaedic surgeon at Rotherham District General Hospital. Fazal Ali FRCS was a specialist registrar at Rotherham, who is now working in Sheffield. Address for Correspondence Victoria Dickens, 7 Summerhill Close, Sharples, Bolton BL1 7BR. Email [email protected]
References Bollen, S R and Scott, B W (1996). ‘Rupture of the anterior cruciate ligament: A quiet epidemic?’ Injury, 27, 6, 407-409. Byles, S E, Ling and R S M (1989). ‘Orthopaedic outpatients: A fresh approach’, Physiotherapy, 75, 435-437. Daker-White, G, Carr, A J, Harvey, I, Woolhead, G, Bannister, G, Nelson, I and Kammerling, M (1999). ‘A randomised controlled trial: Shifting boundaries of doctors and physiotherapists in orthopaedic outpatient departments’, Journal of Epidemiology and Community Health, 53, 643-650. Durrell, S (1996). ‘Expanding the scope of physiotherapy: Clinical physiotherapy specialists in consultants’ clinics’, Manual Therapy, 1, 4, 210-213. Gardiner, J and Turner, P (2002). ‘Accuracy of clinical diagnosis of internal derangement of the knee by extended scope physiotherapists and orthopaedic doctors’, Physiotherapy, 88, 3, 153-157. Hockin, J and Bannister, G (1994). ‘The extended role of a physiotherapist in an outpatient orthopaedic clinic’, Physiotherapy, 80, 5, 281-284.
Kiff, R S and Sykes, P A (1988). ‘Who undertakes the consultations in the outpatient department?’ British Medical Journal, 296, 1511-12. Lawson, G M and Nutton, R W (1995). ‘Accuracy of clinical diagnosis and therapeutic value of 325 knee arthroscopies’, Journal of the Royal College of Surgeons of Edinburgh, 40, 135-137. Lui, S H, Osti, L, Henry, M and Bocchi, L (1995). ‘The diagnosis of acute complete tears of the anterior cruciate ligament: Comparison of magnetic resonance imaging, arthrometry and clinical examination’, Journal of Bone and Joint Surgery, 77-B, 4, 586-588. Noble, J (1992). ‘Unnecessary arthroscopy’, Journal of Bone and Joint Surgery (Br), 74, 6, 797-798. Oberlander, M A, Shalvoy, R M and Hughston, J C (1993). ‘The accuracy of clinical knee examination documented by arthroscopy: A prospective study’, American Journal of Sports Medicine, 21, 6, 773-778. O’Shea, K J, Murphy, K P, Heekin, R D and Herzwurm, P J (1996). ‘The diagnostic accuracy of history, physical examination and radiographs in the evaluation of traumatic
Presentations ‘Can physiotherapists be used to assess acute knee injuries in outpatient clinics?’ by F Ali, V Dickens, H Gent and A Rees was presented at the 2001 spring meeting of the British Association for Knee Surgery in Norwich. Abstract published in BMJ. ‘Assessment and diagnosis of knee injuries: The value of an experienced physiotherapist’ was presented as a poster by V Dickens, F Ali, H Gent and A Rees at the 2001 annual congress of the British Orthopaedic Association in Birmingham.
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knee disorders’, American Journal of Sports Medicine, 24, 2, 164-167. Post, W R and Fulkerson, J (1994). ‘Knee pain diagrams: Correlation with physical examination findings in patients with anterior knee pain’, Arthroscopy, 10, 6, 618-623. Simonsen, O, Jensen, J, Mouristen, P and Lauritzen, J (1984). ‘The accuracy of clinical examination of injury of the knee joint’, Injury, 16, 2, 69-101. Terry, G C, Tagert, B E and Young, M J (1995). ‘Reliability of the clinical assessment in predicting the cause of internal derangements of the knee’, Arthroscopy, 11, 5, 568-576.
Weale, A E and Bannister, G C (1995). ‘Who should see orthopaedic outpatients – physiotherapists or surgeons?’ Annals of the Royal College of Surgeons of England (suppl) 77, 71-73. Weinstabl, R, Muellner, T, Vecsei, V, Kainberger, F and Kramer, M (1997). ‘Economic considerations for the diagnosis and therapy of meniscal lesions: Can magnetic resonance imaging help reduce the expense?’ World of Surgery, 21, 363-368.
Key Messages ■ Use of experienced physiotherapists in knee clinics can help to make up for the reduction in junior doctors’ hours and reduce waiting times for orthopaedic outpatients. ■ Experienced physiotherapists working in this role need good working relationships with consultant orthopaedic surgeons.
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■ Improved standards of assessment and diagnosis of knee injuries can be achieved by using an experienced physiotherapist who has received the correct training and support.
417 Key Words Extended scope, clinical diagnosis, knee injuries, arthroscopy, orthopaedic outpatient clinics.
Assessment and Diagnosis of Knee Injuries
by Victoria Dickens Fazal Ali Helen Gent A Rees
The value of an experienced physiotherapist
Summary A range of titles now reflects emerging roles in physiotherapy: clinical specialists, extended scope practitioners, and more recently consultant therapists. While each role is essentially different, what people in these roles have in common is experience. There is a move to cut down patient waiting times both for operations and for orthopaedic consultant outpatient appointments. An experienced physiotherapist with additional skills would help achieve a reduction in patient waiting times, being able to triage patients for either conservative treatment or a consultant appointment. This study investigates physiotherapists’ diagnostic accuracy of acute knee injuries and answers the question: ‘Can a physiotherapist manage the diagnosis of patients presenting with an acute knee injury safely and effectively?’ This is a prospective study investigating the agreement between physiotherapists’ clinical diagnoses and arthroscopic diagnosis of the knee. Fifty consecutive new patients referred to one consultant’s acute knee clinic were recruited into the study. Assessment was by a consultant knee surgeon and two experienced physiotherapists in random order. An initial diagnosis was then made. This was compared to final diagnosis, which was mainly based on arthroscopic findings and special investigations. The results show that experienced physiotherapists are able to diagnose acute knee injuries with a high rate of accuracy, sensitivity and specificity.
Dickens, V, Ali, F, Gent, H and Rees, A (2003). ‘Assessment and diagnosis of knee injuries: The value of an experienced physiotherapist’, Physiotherapy, 89, 7, 417-422.
Introduction Physiotherapists are highly experienced in the management of musculoskeletal conditions. Weale and Bannister (1995) found that an experienced physiotherapist who has received additional training is as capable of managing selected orthopaedic outpatients as staff grade orthopaedic surgeons, and can offer an effective ser vice safely in outpatient clinics. Many hospitals currently use senior house officers in outpatient clinics who do not have as much experience as experienced physiotherapists in the management of musculoskeletal cond-
itions. Furthermore, up to half of orthopaedic outpatients are seen by sub-consultant grades (Kiff and Sykes, 1988). Many orthopaedic outpatient waiting lists are long, with the majority of referrals for conditions that do not respond to surgical intervention (Weale and Bannister, 1995). Many of these patients can be best managed by experienced physiotherapists (Hockin and Bannister, 1994. This study examines the ability of experienced physiotherapists both to make a correct diagnosis and to recognise when a patient requires an arthroscopy. The first recorded use of a specially trained physiotherapist as a ‘first line filter system’ for orthopaedic patients not obviously requiring surgical intervention was in Exeter Health Authority in 1986 (Byles and Ling, 1989). Since then, the numbers working in this extended role have rapidly increased. The initial growth in these posts has been linked to efforts to halt the rise in hospital waiting lists, reduce costs and lower junior doctors’ hours of work (Durrell, 1996; DakerWhite et al, 1999). Gardiner and Turner (2002) performed a retrospective audit comparing clinical diagnosis of physiotherapists working in an extended role and orthopaedic surgeons with the results of arthroscopies. This study showed favourable results for physiotherapists working in this role. Physiotherapists are specifically trained in the management of musculoskeletal conditions that do not respond to surgical intervention. Arthroscopic examination of the knee is not a substitute for careful clinical assessment. Noble (1992) discussed several aspects of the uses and misuses of arthroscopy. He questioned: ‘How many arthroscopies are clinically essential preoperatively, and have been beneficial to the patient post-operatively?' The current medical environment requires physicians Physiotherapy July 2003/vol 89/no 7
418
to be critical of the tests that are used (Lawson and Nutton, 1995. Each test should ideally be low cost and provide information that will help with future decisions on how to proceed, with either arthroscopic surgery or non-operative treatment. So if the clinical examination and diagnosis are correct, it is the most cost-effective non-invasive method of diagnosis available. Methodology Fifty consecutive new patients who attended one consultant’s outpatient knee clinic, over a period of ten weeks, were recruited into the study. Patients were excluded if they had any of the following: ■ ■ ■ ■
A confirmed fracture Previous knee surgery Severe osteo-arthritis Referral from another consultant
All recruited subjects were given an information sheet and asked to sign a consent form. It was made clear to all participants that their treatment would not be influenced by inclusion in this study and they all took part on a voluntary basis. Subjects who agreed and consented to take part in the study underwent a clinical assessment by three clinicians (the consultant and two physiotherapists, identified in this study as 1 and 2) in a balanced presentation order. Clinical Assessment All three clinicians were asked to perform a standard assessment that was normal for their working practice. The assessment comprised two sections: Subjective examination An interview including history of the problem, mechanism of injury, previous knee injuries or problems, site, type and behaviour of pain. Objective examination Including observation, ligament testing, meniscal testing, accessory movements of both tibio-femoral and patello-femoral joints and palpation. All the assessments were performed within a similar time limit (five to ten minutes), in a systematic manner and with comparison to the unaffected knee. After the assessment each clinician made an independent diagnosis. Each of the three Physiotherapy July 2003/vol 89/no 7
clinicians’ diagnoses and their decisions between conser vative and operative management were blindly recorded on separate forms. Although each clinician made a decision on the subjects’ management the final decision rested with the orthopaedic consultant. Any patients who were not referred for an arthroscopy were referred for physiotherapy and reviewed six to eight weeks later by the orthopaedic consultant. For the purpose of this study, and although there are limitations to this method, if these patients improved with conservative treatment and did not undergo an arthroscopy the consultant’s diagnosis was deemed to be correct, even when disagreement in diagnoses occurred. All arthroscopies were performed by, or under the supervision of, the same consultant who was an experienced arthroscopist. The clinical diagnoses were then compared to the diagnosis made at arthroscopy and the data were analysed. Each lesion was analysed to determine the sensitivity, specificity and accuracy of the diagnosis. The following definitions were used to calculate the percentages of patients with or without each lesion. Using a medial meniscal tear as an example: ■ A true positive is when a medial meniscal tear is suspected and then confirmed at arthroscopy. ■ A true negative is when examination has not indicated a tear and none is found at arthroscopy. ■ A false positive is when a tear is suspected, but not found. ■ A false negative is when a tear is not suspected but one is found. Sensitivity The sensitivity of a diagnostic test reflects the ability of the test to diagnose correctly a lesion which is present (true positive). The greater the sensitivity of the test, the more likely it will detect the lesion. Specificity Specificity reflects the ability of the test to determine correctly that a lesion is not present (true negative). The greater the specificity the more likely it is that patients who do not have a lesion will be excluded by the test.
Research report
Accuracy Accuracy is defined as the ability to detect correctly all cases who do have a particular lesion (true positive) and those who do not (true negative) in a set population. Results Characteristics of Subjects The final sample comprised 50 patients, 36 men and 14 women. There was no age limit for this study and patients recruited were aged between 16 and 64 years. Results of Clinical Diagnosis Of the 50 patients, 33 had an arthroscopy and 17 had conservative management. Conservative Treatment A total of 17 patients had conservative treatment after assessment. Table 1 shows the diagnoses for these patients and highlights the disagreements in diagnosis between clinicians. All these patients improved. The consultant’s diagnosis was the one on which treatments were based. Arthroscopy A total of 33 patients had an arthroscopy following assessment. Table 2 shows their confirmed diagnosis (single and multiple lesions). It illustrates the patients who had multiple lesions within their knees. The incidence of meniscal injuries associated with anterior cruciate ligament tears was high, five of the 13 knees with anterior cruciate ligament injuries had meniscal tears; three had medial meniscal tears and two had lateral meniscal tears. Similarly the three patients with patello-femoral pain syndrome who were chosen to have an arthroscopy did so as a plica was also suspected; this was confirmed, and dealt with at arthroscopy. Analysis of Results Table 3 shows the sensitivity, specificity and accuracy of the diagnosis made by each clinician with respect to the most common injuries found (medial meniscus, lateral meniscus, anterior cruciate ligament and patello-femoral pain syndrome). The correct initial diagnosis in this study was made by the consultant in 92% of cases, by physiotherapist 1 in 84% of cases and by physiotherapist 2 in 80% of cases.
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Table 1: Diagnoses for all patients who had conservative management (n = 17) Level of agreement
Conservative diagnosis
Numbers of subjects
All three clinicians in agreement
Patello-femoral pain syndrome Osteo-arthritis Other (pre-patellar bursitis)
10 2 1
Disagreement between two or more clinicians
Patello-femoral pain syndrome versus lateral meniscal tear Patello-femoral pain syndrome versus medial meniscal tear Osteo-arthritis versus lateral meniscal tear Osteo-arthritis versus loose body
1 1 1 1
Table 2: Patients who had an arthroscopy and their confirmed diagnosis (single and multiple lesions) (n = 33) Type of lesion
Arthroscopy diagnosis
Number of subjects
Single
Anterior cruciate ligament Medial collateral ligament Medial meniscus Lateral meniscus Osteo-arthritis Loose body
8 1 7 4 2 1
Multiple
Anterior cruciate ligament + medial meniscus Anterior cruciate ligament + lateral meniscus Anterior cruciate ligament + medial collateral ligament Patello-femoral pain syndrome + plica Posterior cruciate ligament + medial collateral ligament
3 2 1 3 1
Table 3: Sensitivity, with percentage (95% ‘exact’ confidence interval), specificity and accuracy of each clinician’s diagnosis of the most common injuries – medial meniscus, lateral meniscus, anterior cruciate ligament and patello-femoral pain syndrome Clinician
Sensitivity (%)
Specificity (%)
Accuracy (%)
Anterior cruciate ligament Consultant Physiotherapist 1 Physiotherapist 2
100 (77-100) 93 (66-100) 69 (52-92)
100 97 98
100 98 94
63 (44-97) 63 (44-97) 44 (26-88)
98 98 98
96 94 96
40 (7-93) 40 (7-93) 40 (7-93)
100 98 98
98 96 96
100 92 92
100 98 98
Medial meniscus Consultant Physiotherapist 1 Physiotherapist 2 Lateral meniscus Consultant Physiotherapist 1 Physiotherapist 2
Patello-femoral pain syndrome Consultant Physiotherapist 1 Physiotherapist 2
100 (75-100) 92 (64-99) 92 (64-99)
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Discussion The purpose of this study was to investigate the question: ‘Can experienced physiotherapists manage the diagnosis of patients presenting with knee injuries safely and effectively?’ It also looks into whether or not an experienced physiotherapist can fulfil the role of an orthopaedic consultant’s assistant in outpatient clinics. Terry et al (1995) concluded that a thorough clinical assessment could provide enough information to make a definitive pre-operative diagnosis. They investigated 206 patients (216 knees) and were correct with the primary preoperative clinical diagnosis in 175 knees (81%), with an overall accuracy of 93%. Oberlander et al (1993) also found that clinical examination of the knee had an accuracy of 93%. O’Shea et al (1996) looked prospectively at 156 knees and concluded that the overall assessment of knees was accurate in 89% of cases. Bollen and Scott (1996) retrospectively investigated an apparent poor accuracy of diagnosis by referring doctors for patients with anterior cruciate ligament ruptures. He reported that the original physician had made the correct diagnosis in only 9.8% of cases. This highlights the need for patients to be assessed by an experienced clinician (doctor or physiotherapist) with a special interest in knee injuries. We have shown that experienced physiotherapists have an excellent rate of diagnostic accuracy with respect to anterior cruciate ligament injuries. In this study anterior cruciate ligament tears were diagnosed with an accuracy of 98% by physiotherapist 1 and 94% by physiotherapist 2. Previous studies report between 67% and 99% accuracy (O’Shea et al, 1996; Oberlander et al, 1993; Simonsen et al, 1984). In 39 knees that had arthroscopic examination, we found ten medial meniscal tears and six lateral meniscal tears. Lateral meniscal tears were difficult to diagnose especially when associated with anterior cruciate ligament tears. The sensitivity of diagnosing an isolated lateral meniscal tear by all three clinicians was only 40%. These results are comparable with many previous studies on the clinical accuracy of diagnosing meniscal lesions (Oberlander et al, 1993; O’Shea et al, Physiotherapy July 2003/vol 89/no 7
1996). They are also comparable with the reported accuracy of magnetic resonance imaging (Weinstabl et al, 1997; Lui et al, 1995; Miller, 1996). In this study only four patients presented with isolated lateral meniscal tears. Due to this low number, if one of these patients were diagnosed incorrectly it had a large effect on the results. It is generally agreed that anterior knee pain and patello-femoral problems should be managed conservatively with physiotherapy. Post and Fulkerson (1994) state that accurate questioning and clinical examination are essential for correct diagnosis of these problems. An arthroscopy is not necessary to diagnose patellofemoral problems and can sometimes be inconclusive, so that a patient may undergo an operative procedure for nothing. In this study all 15 patients diagnosed on presentation with patello-femoral pain syndrome proceeded to have a favourable outcome with the chosen management. No firm conclusions should be made about the accuracy of diagnosis of lesions in the smallest groups, eg loose bodies and osteo-arthritis, which each included only one patient It should also be noted that the specificity of the test results may be overestimated (true negatives) because it is not possible to know whether those who did not receive an arthroscopy had a lesion. If after clinical examination and diagnosis, arthroscopy was not the chosen treatment, the most common intervention was physiotherapy. Seventeen patients presenting with a knee injury in this study did not receive an arthroscopy. All of these patients had a course of physiotherapy and symptoms had improved when reassessed by the consultant six weeks later. Not all physiotherapists are experts. The physiotherapists in this study were experienced in the field of orthopaedics and had a special interest in knee injuries, with an average of five years’ clinical experience as a senior physiotherapist working in orthopaedics. Although musculoskeletal assessment forms a substantial part of physiotherapy undergraduate and orthopaedic postgraduate education, physiotherapy specialists should aim to per form this type of assessment in the same way as a surgeon,
Research report
ie diagnosing to ensure those patients who need further investigations get them. A physiotherapist working in an extended role needs to be able to adapt accordingly. Good communication is essential to the success of these projects. This includes consultant and general practitioner support, open access to medical advice, including an immediate opinion if necessary, and cross-referral. It is recognised that this was a small sample and because there were a number of different categories of diagnosis it meant that there were very small numbers of subjects in some categories, for example lateral meniscal tears. This could have had an effect on the results and made comparison to results of other studies limited. The results of this study and previous literature show that diagnosis of lateral meniscal tears is more difficult than other lesions. The clinical tests for diagnosis of lateral meniscal tears should be revisited to try and find a test which is more sensitive. Additionally, only two physiotherapists took part in this study. It is recommended that this study should
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be repeated on a larger scale with more patients and more clinicians. Multiple lesions commonly occur following injury, but the problem of diagnosing them, apart from meniscal and anterior cruciate ligament tears, has not been widely reported. Further research should be completed to consider the accuracy of clinical assessment when there is more than one lesion inside the knee. This study looking at physiotherapy assessment skills did not look into the accuracy of diagnosis of multiple lesions, which could be investigated further at a later date. However, looking at things simply a physiotherapist, working in this capacity, needs to be able to decide whether a patient needs an arthroscopy or not. This study has shown that an experienced physiotherapist is able to do this in most cases by accurately diagnosing the main lesion. The use of experienced physiotherapists as orthopaedic assistants in outpatient clinics may be a realistic and effective solution to the problems created by long waiting lists and junior medical staff in clinics.
Authors Victoria Dickens MSc MCSP was a senior physiotherapist at Rotherham District General Hospital and is now a clinical specialist at Hope Hospital, Salford. Helen Gent BSc MCSP is a senior physiotherapist and Miss A Rees FRCS is a consultant orthopaedic surgeon at Rotherham District General Hospital. Fazal Ali FRCS was a specialist registrar at Rotherham, who is now working in Sheffield. Address for Correspondence Victoria Dickens, 7 Summerhill Close, Sharples, Bolton BL1 7BR. Email [email protected]
References Bollen, S R and Scott, B W (1996). ‘Rupture of the anterior cruciate ligament: A quiet epidemic?’ Injury, 27, 6, 407-409. Byles, S E, Ling and R S M (1989). ‘Orthopaedic outpatients: A fresh approach’, Physiotherapy, 75, 435-437. Daker-White, G, Carr, A J, Harvey, I, Woolhead, G, Bannister, G, Nelson, I and Kammerling, M (1999). ‘A randomised controlled trial: Shifting boundaries of doctors and physiotherapists in orthopaedic outpatient departments’, Journal of Epidemiology and Community Health, 53, 643-650. Durrell, S (1996). ‘Expanding the scope of physiotherapy: Clinical physiotherapy specialists in consultants’ clinics’, Manual Therapy, 1, 4, 210-213. Gardiner, J and Turner, P (2002). ‘Accuracy of clinical diagnosis of internal derangement of the knee by extended scope physiotherapists and orthopaedic doctors’, Physiotherapy, 88, 3, 153-157. Hockin, J and Bannister, G (1994). ‘The extended role of a physiotherapist in an outpatient orthopaedic clinic’, Physiotherapy, 80, 5, 281-284.
Kiff, R S and Sykes, P A (1988). ‘Who undertakes the consultations in the outpatient department?’ British Medical Journal, 296, 1511-12. Lawson, G M and Nutton, R W (1995). ‘Accuracy of clinical diagnosis and therapeutic value of 325 knee arthroscopies’, Journal of the Royal College of Surgeons of Edinburgh, 40, 135-137. Lui, S H, Osti, L, Henry, M and Bocchi, L (1995). ‘The diagnosis of acute complete tears of the anterior cruciate ligament: Comparison of magnetic resonance imaging, arthrometry and clinical examination’, Journal of Bone and Joint Surgery, 77-B, 4, 586-588. Noble, J (1992). ‘Unnecessary arthroscopy’, Journal of Bone and Joint Surgery (Br), 74, 6, 797-798. Oberlander, M A, Shalvoy, R M and Hughston, J C (1993). ‘The accuracy of clinical knee examination documented by arthroscopy: A prospective study’, American Journal of Sports Medicine, 21, 6, 773-778. O’Shea, K J, Murphy, K P, Heekin, R D and Herzwurm, P J (1996). ‘The diagnostic accuracy of history, physical examination and radiographs in the evaluation of traumatic
Presentations ‘Can physiotherapists be used to assess acute knee injuries in outpatient clinics?’ by F Ali, V Dickens, H Gent and A Rees was presented at the 2001 spring meeting of the British Association for Knee Surgery in Norwich. Abstract published in BMJ. ‘Assessment and diagnosis of knee injuries: The value of an experienced physiotherapist’ was presented as a poster by V Dickens, F Ali, H Gent and A Rees at the 2001 annual congress of the British Orthopaedic Association in Birmingham.
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knee disorders’, American Journal of Sports Medicine, 24, 2, 164-167. Post, W R and Fulkerson, J (1994). ‘Knee pain diagrams: Correlation with physical examination findings in patients with anterior knee pain’, Arthroscopy, 10, 6, 618-623. Simonsen, O, Jensen, J, Mouristen, P and Lauritzen, J (1984). ‘The accuracy of clinical examination of injury of the knee joint’, Injury, 16, 2, 69-101. Terry, G C, Tagert, B E and Young, M J (1995). ‘Reliability of the clinical assessment in predicting the cause of internal derangements of the knee’, Arthroscopy, 11, 5, 568-576.
Weale, A E and Bannister, G C (1995). ‘Who should see orthopaedic outpatients – physiotherapists or surgeons?’ Annals of the Royal College of Surgeons of England (suppl) 77, 71-73. Weinstabl, R, Muellner, T, Vecsei, V, Kainberger, F and Kramer, M (1997). ‘Economic considerations for the diagnosis and therapy of meniscal lesions: Can magnetic resonance imaging help reduce the expense?’ World of Surgery, 21, 363-368.
Key Messages ■ Use of experienced physiotherapists in knee clinics can help to make up for the reduction in junior doctors’ hours and reduce waiting times for orthopaedic outpatients. ■ Experienced physiotherapists working in this role need good working relationships with consultant orthopaedic surgeons.
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■ Improved standards of assessment and diagnosis of knee injuries can be achieved by using an experienced physiotherapist who has received the correct training and support.