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The value of radiography in the management of rheumatoid arthritis
ClinicalRadiology (1983) 34, 413-416 © 1983 Royal College of Radiologists
0009-9260/83/01320413502.00
The Value of Radiography in the Management of Rheumatoid Arthritis J. C. W. EDWARDS, S. E. EDWARDS and E. C. HUSKISSON
Departments of Rheumatology and Radiology, St Bartholomew's Hospital, London All radiographs of joints requested on 50 consecutive clinic patients with rheumatoid arthritis were reviewed; 1094 films were available. With few minor exceptions, all information relevant to diagnosis and medical management was provided by one view of each joint: postero-anterior hands, dorsi-planar feet, antero-posterior (AP) elbow, AP shoulder, AP pelvis and lateral flexion cervical spine. Norgaard's 'ballcatcher's' projection of the hands provided no extra information. Radiographs of the hands were consistently more sensitive in showing progression of erosion than those of the feet. Radiography of both hands and feet was required to avoid missing earliest erosions. Radiographs requested at times when drug treatment was under review did not consistently affect decisions, which were largely dependent on clinical findings.
Radiography of joints provides a permanent record of pathological changes in patients with rheumatoid arthritis. However, it is costly, time consuming and a potential hazard to the patient when repeated regularly over a long period. In general, radiography can only be justified if it contributes to decisions on patient management. In the present study all the joint radiographs requested on a group of 50 patients with rheumatoid arthritis were reviewed with this object in mind.
RESULTS
One thousand and ninety-four radiographs were available in the patients' files. Another estimated 200-300 radiographs referred to in the case notes had been lost or destroyed. Table 1 shows the number of different projections or examinations obtained in different joints.
Information Derived from Individual Views METHOD
Hands
Fifty consecutive clinic patients with seropositive rheumatoid arthritis were studied. Thirty-six were female and 14 male. The duration of the disease ranged from 1 to 38 years, with a mean of 14 years. The duration of follow-up in the rheumatology clinic ranged from 1 month to 28 years, with a mean of 8 years. All available radiographs of joints were examined. The information provided by each film was assessed on the radiologist's report combined with a reassessment by a rheumatologist (J.C.W.E.). In the case of significant discrepancy in assessment, the films were reviewed with a radiologist (S.E.E.) and an agreed assessment made. Any management decision made at the time of the request for radiographs was recorded, on the basis of the patient's hospital records. Particular attention was paid to whether or not radiographs contributed to these decisions.
Postero-anterior (PA) views of the hands showed erosions or narrowing of the joint space in all but 18 films. Serial views of the hands frequently showed progression of bone or cartilage damage. In 30 of 123 instances where the hands were X-rayed a ballcatcher's (anterio-posterior (AP) oblique) view was obtained, sometimes at the suggestion of the radiolegist. In no instance did the ballcatcher's view demonstrate erosion or cartilage loss when this was not visible on the standard PA view. Progressive erosion was not seen on the ballcatcher's view in the absence of progression on the PA view. Early focal demineralisation around joints was seen on the PA view in two cases where it was less obvious on the ballcatcher's view. Where serial views of hands and feet showed progressive erosion, this was always evident in the hands. In eight instances no progression occurred in the feet, despite progression in the hands. This suggests that
414
CLINICAL RADIOLOGY
Table 1 - Radiographs available from 50 patients Joint
Number or films
Hands, PA Hands, ballcatcher's view (AP oblique) Single hand, PA Feet, DP Feet, DP oblique or lateral Single foot, DP Elbow, AP Elbow, lateral Elbow prosthesis, AP Elbow prosthesis, lateral Elbow prosthesis, arthrogram Shoulder, AP Shoulder, axial Shoulder prosthesis, AP Shoulder prosthesis, axial Cervical spine, AP Cervical spine, lateral Cervical spine, oblique Cervical spine, lateral flexion Cervical spine, lateral extension Cervical spine, odontoid peg view Knees, AP Knee lateral Single knee, AP Skyline view Knee prosthesis, AP Knee prosthesis, lateral Knee prosthesis, skyline Knee prosthesis, arthrogram Ankle, AP Ankle, lateral Ankle prosthesis, AP Ankle prosthesis, lateral Pelvis, AP Pelvis, with THR Hip, arthrogram Hip, lateral Hip, with pin in situ Wrist Thoracic spine Lumbar spine and sacro-iliac joints Temporomandibular joint Thumb, with wire
123 30 10 79 30 6 39 38 4 4 3 37 15 10 6 32 26 37 23 24 7 86 119 10 1 21 28 3 17 31 29 3 2 25 39 1 1 10 37 7 33 7 1
the hands are the more sensitive indicator o f progression o f erosion. In 32 instances radiographs of the hands and feet were performed together at the time when erosions were first demonstrated. I n 29 o f these, erosions were present in the hands but in the other three cases, erosions were only present in the feet. This suggests that radiography o f both hands and feet is necessary to show earliest erosions in all cases. Feet
Lateral or dorsi-planar (DP) oblique views of the feet did n o t provide any more information about the
presence o f erosions or progression of disease than the DP view. In one instance of metatarsal fracture (suspected clinically) the fracture was visible on b o t h DP and DP oblique views. Elbows
Erosive change and loss o f joint space was seen best on AP views o f the elbow. No additional information was obtained from lateral views other than the extent o f osteophyte formation in cases with marked secondary bone sclerosis. ShouMers
As with the elbow, a single AP view provided all the information and additional views contributed nothing further. Cervical Spine
The projections of the cervical spine varied considerably and included AP, lateral, obliques, lateral in flexion and extension and an open-mouth view o f the odontoid. The m a x i m u m number of views requested at any one examination was seven. Over the period 1 9 6 5 - 8 2 , the number o f oblique views requested diminished and the number of flexion and extension views increased, presumably reflecting increasing awareness of the problems o f rheumatoid subluxation. No useful positive information was gained from AP or oblique views of the cervical spine. Lateral views were n o t e d to show coincident 'degenerative change' on 10 occasions b y the radiologist making the original report. On review, many o f the other films showed some degree of osteophyte formation or disc space narrowing, as would be expected from patients o f this age. All the information provided by the lateral view was also given b y a lateral flexion view. The combination of lateral flexion and lateral extension views demonstrated subluxation at the aflanto-axial level in five of 23 cases. In all cases the presence o f subluxation could be established on the flexion view alone. Seven views o f the odontoid process showed irregularity of its lateral margins in only one case. No subluxation below C2 was found in this series. Kn ees Antero-posterior views of the knees showed variable degrees of erosion of the femoral condyles, tibio-femoral j o i n t space narrowing (in one or both compartments) and collapse o f the tibial plateau. Lateral views provided no further information other than the degree o f loss o f j o i n t space in the pateUofemoral j o i n t and the orientation o f a femoral osteo-
RADIOGRAPHY
IN R H E U M A T O I D
tomy post-operatively in one case. No erosions were seen on lateral views. A pateUar skyline view was requested pre-operatively on a single occasion by the orthopaedic team, to assess the position of the patella in a patient with valgus deformity.
Ankles Similarly, the AP view was adequate to assess narrowing of the joint space and erosion. Secondary sclerosis and osteophyte formation was relatively prominent in ankle joints and the lateral view displayed this as well as the AP view.
Wrists In all cases where the wrist was X-rayed, except immediately following surgery, radiography of the hand had also been requested. The PA view of the wrist merely duplicated the proximal part of the hand film. Lateral views of the wrist were uninformative.
Thoracic and Lumbar Spine and Sacro-iliac Joints Radiographs of the truncal spine and sacro-iliac joints were either normal or showed degenerative changes.
Prostheses The position of surgical prostheses could only be established from two separate views; additional views showed the range of movement as well. In five cases the position of a prosthesis was considered sufficiently unsatisfactory to warrant correction.
Radiographs in Making Clinical Decisions The contribution to management decisions made by the information derived from radiographs was assessed as accurately as possible from the case notes. The diagnosis of rheumatoid arthritis was made on the basis of erosions on a hand radiograph in one patient. In another patient with a symmetrical polyarthritis a positive Rose Waaler was available at the same time as the radiographs, which showed erosions. In all other cases the diagnosis was made clinically. In four cases the diagnosis was missed at a time when radiographs were reported as normal although, on review, two of these showed erosions or narrowing of the joint space. Progression of erosions on radiographs of the hands or feet contributed to a decision to start gold, penicillamine or levamisole therapy in nine out of 278 radiographs. In seven cases where erosions were
ARTHRITIS
415
absent or static, a decision to start such a drug was deferred. In all other cases where decisions were made on starting these drugs, the information from radiographs was ignored or the decision was made before radiographs were available. One radiograph of a foot was requested to exclude osteomyelitis and another to confirm a metatarsal fracture already suspected clinically. At presentation, many patients had radiographs of a number of joints other than hands and feet (knee 60, ankle 18, elbow 14, shoulder 13, wrist l l and hip four). These examinations did not affect any treatment decisions. Similarly, on admission to hospital, radiographs of several joints were often requested (knee 16, ankle 13, elbow 13, shoulder eight, hip five and wrist two~ when no treatment decisions relating to these particular joints depended on radiographic findings. At the time of starting trea~nent with penicillamine the hands and feet were usually X-rayed but, on occasion, other joints were X-rayed as well (31 views in total). Two hundred and ninety-five radiographs were requested in relation to joint surgery. It seems reasonable to assume that the radiographic appearances of joints contributed in some cases to the decision on appropriate surgical treatment. However, the case notes contained no specific reference to this. The value of immediate pre-operative films was often unclear but post-operative films were of value in checking the position of prostheses. In five cases surgical revision was undertaken on the basis of radiographic findings. Forty-four radiographs of the truncal spine or pelvis were ordered when patients complained of intercurrent back pain. Fourteen radiographs had been requested to look for pelvo-spondylitis in patients with psoriasis who had otherwise typical seropositive rheumatoid arthritis. One hundred and forty films (knee 61, elbow 36, wrist nine, temporomandibular joint seven, shoulder 20 and pelvis eight) were requested when a joint was painful but where there appeared to be no management decision that could depend on the radiographic findings, unless a fracture was being considered.
DISCUSSION The results of this study indicate that we are not making the best use of radiology ill the management of rheumatoid arthritis. Certain views, which may be of value in other clinical situations, provide so little information that their routine use in rheumatoid
416
CLINICAL RADIOLOGY
arthritis is difficult to justify. The value of radiographic information in making clinical decisions is much more difficult to analyse, but the present study probably indicates a lack of any systematic approach to the use of radiographs in planning therapy. The main reason for taking two views of a part of a limb is to demonstrate unexpected pathology, particularly fractures. There is no doubt that unsuspected fractures are occasionally seen on radiographs of patients with rheumatoid arthritis with acute pain in one particular area. In these circumstances, clearly, two views should be requested. On the other hand, most radiographs on patients with rheumatoid arthritis are requested to assess the extent of joint involvement and some rationalisation should be possible. Norgaard (1965) suggested that an AP oblique view of the hands could show rheumatoid erosions earlier than the PA view. This AP oblique or 'ballcatcher's' view has become almost routine. However, Norgaard gave no indication as to how often this view was informative; the present study suggests that such instances are rare. There is certainly no reason to take an AP oblique view when erosions have already been demonstrated and it is of little value in follow-up, partly because it is difficult to standardise the position. Macroradiography using fine-grain industrial trim may be preferable for showing early bone changes. However, it is doubtful how useful detection of very minor changes is, since these have little or no functional significance in themselves and may not progress. The duplication of hand and wrist radiographs indicates a failure of communication between radiologist and rheumatologist. A request for 'PA hands to include wrists' should ensure an adequate view of both on a single film. In this series views of the hands were consistently more sensitive in showing progression of erosion than views of the feet. It would be reassuring to confirm this on a larger series but the present findings strongly suggest that a film of the hands alone is a reliable way of assessing progression of small joint erosion. When the cervical spine is X-rayed to exclude unexpected pathology, an AP view is justified. Most cervical spine views were requested specifically to assess instability before a general anaesthetic;in this
situation a lateral flexion view seems sufficient. If subluxation below C2 is shown on this view, an extension view may also be helpful, although all rheumatoid patients should have neck protection during surgery anyway. There appears to be no reason for requesting a plain lateral on a rheumatoid patient. Views of the knees are often repeated because the initial view was not taken weightbearing, again indicating poor communication between the specialties. Lateral views of the knee provided little information in this series. The loss in depth of patellofemoral cartilage may be of specific interest, especially to the surgeon, but did not affect management in this series. Follow-up views of the hands and feet are requested as an aid to managing gold or penicillamine treatment. Emphasis tends to be put on erosions rather than loss of joint space, perhaps because erosions are more 'specific' to rheumatoid arthritis. No particular justification exists for this since many rheumatologists consider that loss of joint space is more closely related to loss of function. It is not even clear whether radiographic findings should contribute to decisions on therapy at all. Arguably, all patients with progressing functional problems deserve a trial of either gold or penicillamine. Those without functional problems or clinical evidence of progression tend not to be X-rayed. In order to use radiography logically we would need to X-ray all rheumatoid patients at 6 monthly intervals. It is beyond the scope of this study to consider the value of radiography in the surgical management of this disease. We suspect that many of the same considerations apply, although detailed bone and cartilage changes may be of'more importance to the surgeon in deciding on treatment. It is our opinion that a more selective and logical approach to the radiography of rheumatoid patients is needed. It is of interest that the standard texts on this subject contain no reference to the value of radiographic findings in making specific clinical decisions.
REFERENCES
Norgaard, F. (1965). Earliest roentgenological changes in polyarthritis of the rheumatoid type. Radiology, 85, 325-329.
0009-9260/83/01320413502.00
The Value of Radiography in the Management of Rheumatoid Arthritis J. C. W. EDWARDS, S. E. EDWARDS and E. C. HUSKISSON
Departments of Rheumatology and Radiology, St Bartholomew's Hospital, London All radiographs of joints requested on 50 consecutive clinic patients with rheumatoid arthritis were reviewed; 1094 films were available. With few minor exceptions, all information relevant to diagnosis and medical management was provided by one view of each joint: postero-anterior hands, dorsi-planar feet, antero-posterior (AP) elbow, AP shoulder, AP pelvis and lateral flexion cervical spine. Norgaard's 'ballcatcher's' projection of the hands provided no extra information. Radiographs of the hands were consistently more sensitive in showing progression of erosion than those of the feet. Radiography of both hands and feet was required to avoid missing earliest erosions. Radiographs requested at times when drug treatment was under review did not consistently affect decisions, which were largely dependent on clinical findings.
Radiography of joints provides a permanent record of pathological changes in patients with rheumatoid arthritis. However, it is costly, time consuming and a potential hazard to the patient when repeated regularly over a long period. In general, radiography can only be justified if it contributes to decisions on patient management. In the present study all the joint radiographs requested on a group of 50 patients with rheumatoid arthritis were reviewed with this object in mind.
RESULTS
One thousand and ninety-four radiographs were available in the patients' files. Another estimated 200-300 radiographs referred to in the case notes had been lost or destroyed. Table 1 shows the number of different projections or examinations obtained in different joints.
Information Derived from Individual Views METHOD
Hands
Fifty consecutive clinic patients with seropositive rheumatoid arthritis were studied. Thirty-six were female and 14 male. The duration of the disease ranged from 1 to 38 years, with a mean of 14 years. The duration of follow-up in the rheumatology clinic ranged from 1 month to 28 years, with a mean of 8 years. All available radiographs of joints were examined. The information provided by each film was assessed on the radiologist's report combined with a reassessment by a rheumatologist (J.C.W.E.). In the case of significant discrepancy in assessment, the films were reviewed with a radiologist (S.E.E.) and an agreed assessment made. Any management decision made at the time of the request for radiographs was recorded, on the basis of the patient's hospital records. Particular attention was paid to whether or not radiographs contributed to these decisions.
Postero-anterior (PA) views of the hands showed erosions or narrowing of the joint space in all but 18 films. Serial views of the hands frequently showed progression of bone or cartilage damage. In 30 of 123 instances where the hands were X-rayed a ballcatcher's (anterio-posterior (AP) oblique) view was obtained, sometimes at the suggestion of the radiolegist. In no instance did the ballcatcher's view demonstrate erosion or cartilage loss when this was not visible on the standard PA view. Progressive erosion was not seen on the ballcatcher's view in the absence of progression on the PA view. Early focal demineralisation around joints was seen on the PA view in two cases where it was less obvious on the ballcatcher's view. Where serial views of hands and feet showed progressive erosion, this was always evident in the hands. In eight instances no progression occurred in the feet, despite progression in the hands. This suggests that
414
CLINICAL RADIOLOGY
Table 1 - Radiographs available from 50 patients Joint
Number or films
Hands, PA Hands, ballcatcher's view (AP oblique) Single hand, PA Feet, DP Feet, DP oblique or lateral Single foot, DP Elbow, AP Elbow, lateral Elbow prosthesis, AP Elbow prosthesis, lateral Elbow prosthesis, arthrogram Shoulder, AP Shoulder, axial Shoulder prosthesis, AP Shoulder prosthesis, axial Cervical spine, AP Cervical spine, lateral Cervical spine, oblique Cervical spine, lateral flexion Cervical spine, lateral extension Cervical spine, odontoid peg view Knees, AP Knee lateral Single knee, AP Skyline view Knee prosthesis, AP Knee prosthesis, lateral Knee prosthesis, skyline Knee prosthesis, arthrogram Ankle, AP Ankle, lateral Ankle prosthesis, AP Ankle prosthesis, lateral Pelvis, AP Pelvis, with THR Hip, arthrogram Hip, lateral Hip, with pin in situ Wrist Thoracic spine Lumbar spine and sacro-iliac joints Temporomandibular joint Thumb, with wire
123 30 10 79 30 6 39 38 4 4 3 37 15 10 6 32 26 37 23 24 7 86 119 10 1 21 28 3 17 31 29 3 2 25 39 1 1 10 37 7 33 7 1
the hands are the more sensitive indicator o f progression o f erosion. In 32 instances radiographs of the hands and feet were performed together at the time when erosions were first demonstrated. I n 29 o f these, erosions were present in the hands but in the other three cases, erosions were only present in the feet. This suggests that radiography o f both hands and feet is necessary to show earliest erosions in all cases. Feet
Lateral or dorsi-planar (DP) oblique views of the feet did n o t provide any more information about the
presence o f erosions or progression of disease than the DP view. In one instance of metatarsal fracture (suspected clinically) the fracture was visible on b o t h DP and DP oblique views. Elbows
Erosive change and loss o f joint space was seen best on AP views o f the elbow. No additional information was obtained from lateral views other than the extent o f osteophyte formation in cases with marked secondary bone sclerosis. ShouMers
As with the elbow, a single AP view provided all the information and additional views contributed nothing further. Cervical Spine
The projections of the cervical spine varied considerably and included AP, lateral, obliques, lateral in flexion and extension and an open-mouth view o f the odontoid. The m a x i m u m number of views requested at any one examination was seven. Over the period 1 9 6 5 - 8 2 , the number o f oblique views requested diminished and the number of flexion and extension views increased, presumably reflecting increasing awareness of the problems o f rheumatoid subluxation. No useful positive information was gained from AP or oblique views of the cervical spine. Lateral views were n o t e d to show coincident 'degenerative change' on 10 occasions b y the radiologist making the original report. On review, many o f the other films showed some degree of osteophyte formation or disc space narrowing, as would be expected from patients o f this age. All the information provided by the lateral view was also given b y a lateral flexion view. The combination of lateral flexion and lateral extension views demonstrated subluxation at the aflanto-axial level in five of 23 cases. In all cases the presence o f subluxation could be established on the flexion view alone. Seven views o f the odontoid process showed irregularity of its lateral margins in only one case. No subluxation below C2 was found in this series. Kn ees Antero-posterior views of the knees showed variable degrees of erosion of the femoral condyles, tibio-femoral j o i n t space narrowing (in one or both compartments) and collapse o f the tibial plateau. Lateral views provided no further information other than the degree o f loss o f j o i n t space in the pateUofemoral j o i n t and the orientation o f a femoral osteo-
RADIOGRAPHY
IN R H E U M A T O I D
tomy post-operatively in one case. No erosions were seen on lateral views. A pateUar skyline view was requested pre-operatively on a single occasion by the orthopaedic team, to assess the position of the patella in a patient with valgus deformity.
Ankles Similarly, the AP view was adequate to assess narrowing of the joint space and erosion. Secondary sclerosis and osteophyte formation was relatively prominent in ankle joints and the lateral view displayed this as well as the AP view.
Wrists In all cases where the wrist was X-rayed, except immediately following surgery, radiography of the hand had also been requested. The PA view of the wrist merely duplicated the proximal part of the hand film. Lateral views of the wrist were uninformative.
Thoracic and Lumbar Spine and Sacro-iliac Joints Radiographs of the truncal spine and sacro-iliac joints were either normal or showed degenerative changes.
Prostheses The position of surgical prostheses could only be established from two separate views; additional views showed the range of movement as well. In five cases the position of a prosthesis was considered sufficiently unsatisfactory to warrant correction.
Radiographs in Making Clinical Decisions The contribution to management decisions made by the information derived from radiographs was assessed as accurately as possible from the case notes. The diagnosis of rheumatoid arthritis was made on the basis of erosions on a hand radiograph in one patient. In another patient with a symmetrical polyarthritis a positive Rose Waaler was available at the same time as the radiographs, which showed erosions. In all other cases the diagnosis was made clinically. In four cases the diagnosis was missed at a time when radiographs were reported as normal although, on review, two of these showed erosions or narrowing of the joint space. Progression of erosions on radiographs of the hands or feet contributed to a decision to start gold, penicillamine or levamisole therapy in nine out of 278 radiographs. In seven cases where erosions were
ARTHRITIS
415
absent or static, a decision to start such a drug was deferred. In all other cases where decisions were made on starting these drugs, the information from radiographs was ignored or the decision was made before radiographs were available. One radiograph of a foot was requested to exclude osteomyelitis and another to confirm a metatarsal fracture already suspected clinically. At presentation, many patients had radiographs of a number of joints other than hands and feet (knee 60, ankle 18, elbow 14, shoulder 13, wrist l l and hip four). These examinations did not affect any treatment decisions. Similarly, on admission to hospital, radiographs of several joints were often requested (knee 16, ankle 13, elbow 13, shoulder eight, hip five and wrist two~ when no treatment decisions relating to these particular joints depended on radiographic findings. At the time of starting trea~nent with penicillamine the hands and feet were usually X-rayed but, on occasion, other joints were X-rayed as well (31 views in total). Two hundred and ninety-five radiographs were requested in relation to joint surgery. It seems reasonable to assume that the radiographic appearances of joints contributed in some cases to the decision on appropriate surgical treatment. However, the case notes contained no specific reference to this. The value of immediate pre-operative films was often unclear but post-operative films were of value in checking the position of prostheses. In five cases surgical revision was undertaken on the basis of radiographic findings. Forty-four radiographs of the truncal spine or pelvis were ordered when patients complained of intercurrent back pain. Fourteen radiographs had been requested to look for pelvo-spondylitis in patients with psoriasis who had otherwise typical seropositive rheumatoid arthritis. One hundred and forty films (knee 61, elbow 36, wrist nine, temporomandibular joint seven, shoulder 20 and pelvis eight) were requested when a joint was painful but where there appeared to be no management decision that could depend on the radiographic findings, unless a fracture was being considered.
DISCUSSION The results of this study indicate that we are not making the best use of radiology ill the management of rheumatoid arthritis. Certain views, which may be of value in other clinical situations, provide so little information that their routine use in rheumatoid
416
CLINICAL RADIOLOGY
arthritis is difficult to justify. The value of radiographic information in making clinical decisions is much more difficult to analyse, but the present study probably indicates a lack of any systematic approach to the use of radiographs in planning therapy. The main reason for taking two views of a part of a limb is to demonstrate unexpected pathology, particularly fractures. There is no doubt that unsuspected fractures are occasionally seen on radiographs of patients with rheumatoid arthritis with acute pain in one particular area. In these circumstances, clearly, two views should be requested. On the other hand, most radiographs on patients with rheumatoid arthritis are requested to assess the extent of joint involvement and some rationalisation should be possible. Norgaard (1965) suggested that an AP oblique view of the hands could show rheumatoid erosions earlier than the PA view. This AP oblique or 'ballcatcher's' view has become almost routine. However, Norgaard gave no indication as to how often this view was informative; the present study suggests that such instances are rare. There is certainly no reason to take an AP oblique view when erosions have already been demonstrated and it is of little value in follow-up, partly because it is difficult to standardise the position. Macroradiography using fine-grain industrial trim may be preferable for showing early bone changes. However, it is doubtful how useful detection of very minor changes is, since these have little or no functional significance in themselves and may not progress. The duplication of hand and wrist radiographs indicates a failure of communication between radiologist and rheumatologist. A request for 'PA hands to include wrists' should ensure an adequate view of both on a single film. In this series views of the hands were consistently more sensitive in showing progression of erosion than views of the feet. It would be reassuring to confirm this on a larger series but the present findings strongly suggest that a film of the hands alone is a reliable way of assessing progression of small joint erosion. When the cervical spine is X-rayed to exclude unexpected pathology, an AP view is justified. Most cervical spine views were requested specifically to assess instability before a general anaesthetic;in this
situation a lateral flexion view seems sufficient. If subluxation below C2 is shown on this view, an extension view may also be helpful, although all rheumatoid patients should have neck protection during surgery anyway. There appears to be no reason for requesting a plain lateral on a rheumatoid patient. Views of the knees are often repeated because the initial view was not taken weightbearing, again indicating poor communication between the specialties. Lateral views of the knee provided little information in this series. The loss in depth of patellofemoral cartilage may be of specific interest, especially to the surgeon, but did not affect management in this series. Follow-up views of the hands and feet are requested as an aid to managing gold or penicillamine treatment. Emphasis tends to be put on erosions rather than loss of joint space, perhaps because erosions are more 'specific' to rheumatoid arthritis. No particular justification exists for this since many rheumatologists consider that loss of joint space is more closely related to loss of function. It is not even clear whether radiographic findings should contribute to decisions on therapy at all. Arguably, all patients with progressing functional problems deserve a trial of either gold or penicillamine. Those without functional problems or clinical evidence of progression tend not to be X-rayed. In order to use radiography logically we would need to X-ray all rheumatoid patients at 6 monthly intervals. It is beyond the scope of this study to consider the value of radiography in the surgical management of this disease. We suspect that many of the same considerations apply, although detailed bone and cartilage changes may be of'more importance to the surgeon in deciding on treatment. It is our opinion that a more selective and logical approach to the radiography of rheumatoid patients is needed. It is of interest that the standard texts on this subject contain no reference to the value of radiographic findings in making specific clinical decisions.
REFERENCES
Norgaard, F. (1965). Earliest roentgenological changes in polyarthritis of the rheumatoid type. Radiology, 85, 325-329.