Fractal signature analysis measures cancellous bone organisation in macroradiographs of patients with knee osteoarthritis.

OBJECTIVE: To determine whether fractal signature analysis (FSA) of digitised macroradiographs of knees quantifies alterations in trabecular structure in the tibial cancellous bone of osteoarthritic patients with either early or definite joint space narrowing compared with non-arthritic subjects. METHODS: 90 osteoarthritic knees had macroradiographs at x5 magnification. Joint space width and FSA of horizontal and vertical trabecular organisation in the tibial subarticular cancellous bone were measured in the medial and lateral tibio-femoral compartments and compared to reference values obtained from the knees of 14 healthy non-arthritic volunteers, and to the subject's age and weight. RESULTS: Compared to the non-arthritic joints, FSA of the trabecular structure of the medial diseased compartment of the tibia was significantly different and correlated with the degree of joint space narrowing (P < 0.003); FSA of horizontal trabecular structures decreased (P < 0.001) in knees with early osteoarthritis (joint space > 3 mm) and vertical trabecular FSA increased in knees with marked joint space narrowing (joint space < 3 mm). In the lateral compartment of the tibia, FSA did not show a difference between any of the categories. With increasing age of all subjects, the changes in FSA indicated a significant increase in the number of fine horizontal and vertical trabeculae. No correlation was found between the subjects' body weight and changes in the subarticular cancellous bone organisation. CONCLUSIONS: FSA quantifies changes in cancellous bone organisation in knee osteoarthritis. In the diseased compartment, increased horizontal trabecular thickness occurred early and preceded the later changes in the vertical structures.

Accuracy and precision of joint space width measurements in standard and macroradiographs of osteoarthritic knees.

OBJECTIVES: To improve the reproducibility and accuracy of joint space width (JSW) measurement as an assessment of cartilage loss in patients with osteoarthritis (OA) of the knee by determining how precision and accuracy of JSW measurement were altered by a computerised method of measurement, correction for radiographic magnification, radiography of the knee in the standing semiflexed view, and high definition macroradiography of the knee in the semiflexed view--taking JSW measurements from standard radiographs of OA knees in the extended view as the standard for comparison. METHODS: Twenty five OA and 10 nonarthritic knees were radiographed in the extended view and minimum JSW was measured manually. Conventional and x5 macroradiographs were taken in the semiflexed view. All radiographs were taken twice on the same day and repeated two weeks later. Automated computerised measurement of minimum JSW was obtained from digitally stored images of all radiographs. RESULTS: For medial compartment JSW measurements, computerised was more accurate than manual, correction for radiographic magnification improved precision and accuracy, measurements in the semiflexed view were more precise and accurate, and macroradiography increased measurement precision. For the lateral compartment JSW measurements, correction for radiographic magnification improved precision and accuracy, and the semiflexed view improved precision only. CONCLUSIONS: Protocols defining radiographic and mensural procedures are essential for quality control of knee radiography in the semiflexed view to permit accurate and reproducible measurement of JSW. Macroradiography provides greater precision of JSW measurement.

Sensitivity of radiographic features and specificity of scintigraphic imaging in hand osteoarthritis.

We undertook to determine which of the radiographic features most reliably detected the presence and disease progression in osteoarthritis in the hand; and which of the radiographic features corresponded with the radionuclide bone scan images. 32 patients with osteoarthritis had X 5 macroradiographs taken of their wrists and hands at 6 monthly intervals over an 18 month period. The high magnification and resolution of microfocal radiography permitted quantitative detection of the extent and change in joint space width, subchondral sclerosis, osteophytosis and juxtaarticular radiolucencies. 4-hour technetium 99m methylene bisphosphonate bone scans were taken at 0 and 12 months and the activity of the tracer uptake at each joint scored. The latter was compared with the radiographic features at each visit and the changes between visits analysed. In hand OA the most sensitive radiographic parameters for detecting disease were osteophytes, subchondral sclerosis and juxtaarticular radiolucencies, with radionuclide imaging demonstrating the increased activity in bone formation associated with the growth and remodelling of osteophytes. Changes in the number and size of osteophytes and joint space narrowing were the only reliable and sensitive parameters for assessing disease progression. We conclude that in osteoarthritis, the bony changes progress significantly before the occurrence of radiographically evident joint space narrowing indicative of cartilage thinning.

Quantitative microfocal radiography detects changes in OA knee joint space width in patients in placebo controlled trial of NSAID therapy.

OBJECTIVE: To assess the usefulness of, and define the time course of changes in the features of osteoarthritic (OA) knees measurable using microfocal radiography, and to determine whether it differs in patients taking a nonsteroidal antiinflammatory drug (NSAID). METHODS: Forty-five patients with knee OA were randomly allocated to receive either diclofenac sodium or placebo for 18 months; 33 (17 NSAID, 16 placebo) completed the study. Clinical and 5 x high definition macroradiographic assessments of both knees in standing semiflexed views were carried out at 6-monthly intervals. Precise measurements were taken of the tibial and femoral subchondral thickness and osteophyte size, and of joint space width (JSW) across the narrowest part of the medial and lateral tibiofemoral compartments. RESULTS: In all knees as a group, there was no statistically significant difference in JSW between treatment groups. However, changes in JSW were significantly different (p < 0.04, multivariate analysis of variance) between treatments in 51 knees with early disease, i.e., those with initially > 50% JSW (22 active, 29 placebo), but not in 15 knees with severe disease, i.e., initially < 50% JSW (10 active, 5 placebo). During the study, osteophyte size in all knees and in those with > 50% JSW increased significantly (p < 0.016; p < 0.008) in the placebo group but remained unchanged in the treatment group. No significant changes were detected in subchondral cortical thickness. CONCLUSION: Using microfocal radiography the time course of changes in JSW and osteophyte size of knees with early, but not late OA, was found to differ in both pattern and magnitude in patients receiving NSAID: In knees with late stage OA the JSW progressively decreased irrespective of treatment. The observations may prove useful for the design of future therapeutic trials.

Joint space width measures cartilage thickness in osteoarthritis of the knee: high resolution plain film and double contrast macroradiographic investigation.

OBJECTIVE: To test reliability of joint space width (JSW) measurements as a predictor of cartilage thickness in knees of patients with osteoarthritis (OA), using high definition microfocal radiography. METHOD: JSW was measured from weight bearing plain film macroradiographs taken in the tunnel view and compared with the sum of femoral and tibial cartilage thicknesses measured from double contrast macroarthrograms of the same regions of the same knees obtained in the non-weight bearing lateral position. RESULTS: All knees had medial compartment OA. Comparison of the JSW with the sum of the tibial and femoral cartilage thicknesses revealed a highly significant correlation (p < 0.0001) between the two measurements in the medial but not the lateral compartment. In the middle region of both compartments, JSW was smaller than the cartilage thickness, indicating that, on standing, the curvature of the femoral condyles compressed the cartilage in this region. CONCLUSIONS: JSW reliably measured cartilage thickness in the medial but not the lateral compartment of knees with medial compartment OA. Depending upon the stage of OA disease, JSW reliably reflects cartilage thinning and compression.

Quantitative microfocal radiographic assessment of osteoarthritis of the knee from weight bearing tunnel and semiflexed standing views.

OBJECTIVE: Joint space width (JSW) in osteoarthritis (OA) knee radiography is reported to be optimally assessed from semiflexed standing and tunnel views although no detailed assessment of tunnel view radiography of OA knees has been done. The primary objective of our study was to determine the incidence of joint space narrowing (JSN) in semiflexed standing vs weight bearing tunnel views. The data were also analyzed to examined the degree and relationship of JSN and bony features of OA in the 2 views. METHODS: Ninety OA knees had macroradiographs at 5 times magnification taken in weight bearing standing semiflexed and weight bearing tunnel views. JSW and OA related bony features were measured and compared with reference values obtained from the knees of 14 healthy volunteers without arthritis. RESULTS: Comparison of JSW between the 2 radiographic views identified 3 locations of cartilage loss: JSN recorded in the tunnel only (22%), that in standing view only (8%), and that in both the views (30%). Subchondral sclerosis and osteophytes were significantly larger in 40% of OA knees despite a normal JSW. The tunnel view also enabled better visualization and measurement of osteophytes. CONCLUSION: Standing semiflexed view radiography alone failed to detect JSN in 22% of OA knees. Combined standing and tunnel radiographic views detected JSN more frequently than either view alone. Bony changes were radiographically evident without the presence of JSN indicative of cartilage thinning in as many as 40% of the patients with OA studied.

A comparative study of the efficacy and toxicity of etodolac and naproxen in the treatment of osteoarthritis.

In a two-period, double-blind, crossover study, patients with osteoarthritis of the knee and/or hip received etodolac 300 mg twice daily for 4 weeks and naproxen 500 mg twice daily for 4 weeks in random order. The assessment of efficacy showed that naproxen and etodolac were equally effective in the management of pain and stiffness in osteoarthritis. However, a significantly higher proportion of patients preferred naproxen to etodolac for the relief of pain intensity. The incidence of adverse events caused by either drug was the same.

A study of the early and late 99technetium scintigraphic images and their relationship to symptoms in osteoarthritis of the hands.

Thirty-five patients with OA of the hands had an early and late phase isotope bone scan performed at entry and 1 yr later. Simultaneous assessment of symptoms was made by a visual analogue pain score (VAS) and a tender joint articular index (AI) and comparisons were made between the clinical and scintigraphic findings. Sixty-five percent of joints were classed as positive in the late phase compared to 17% in the early phase scan. Thirteen per cent of joints were positive only in the early phase and 49% only in the late phase. There was no significant overall change in either phase of the scan in 1 yr. The pattern of positive joints showed considerable symmetry and wrist involvement. There was a high degree of correlation between AI and the late phase scan but none with the early phase scan. VAS showed no correlation with the late phase scan but did correlate significantly with the early phase scan at 1 yr.

Precision of joint space width measurement in knee osteoarthritis from digital image analysis of high definition macroradiographs.

The precision of joint space width (JSW) measurements from plain film radiographs of the knee is limited by poor radio-anatomical positioning of the joint and/or insensitive methods of measurement. These limitations were overcome by establishing a precise radio-anatomical position for standing loaded and weight-bearing tunnel views of the knee, using the advantages of high definition macroradiography and a new computerized method for automatic JSW measurement from digitized macroradiographs of the knee. Reproducibility of JSW measurements was obtained from macroradiographs of knees of five post-mortem subjects and 12 patients with osteoarthritis (OA). JSW measurements were altered more by vertical than by horizontal misalignment of the X-ray beam relative to the joint space. In OA knees with medial compartment involvement, JSW measurements were more reproducible in the medial than lateral compartments in both radiographic views. In the medial compartment, the coefficient of variation for joint repositioning was 1% for minimum and 2% for average JSW, and for inter- and intraobserver errors, it was < 1% for both JSW measurements. The precision of this method will permit quantification of changes in JSW associated with disease progression and the treatment of OA.

Relationship between joint space width and subchondral sclerosis in the osteoarthritic hand: a quantitative microfocal radiographic study.

Measurement of joint space width and subchondral sclerosis from x 5 macroradiographic examination of 32 patients with osteoarthritis (OA) of the hand over an 18-month period showed that joint space loss was symmetrical in both hands. Its change showed that over a period of time narrowing progressed proximally from distal interphalangeal to proximal interphalangeal, metacarpalphalangeal and wrist joints. Sclerosis was greatest in those joints at which the largest forces were exerted across the hand in precision, power and pulp-pinch grip, respectively. Our findings suggest that constitutional factors determine the onset of cartilage changes in OA which in turn result in subchondral sclerosis, the extent of which is determined by the pattern of normal forces within the hand.

Comparison of clinical, radionuclide, and radiographic features of osteoarthritis of the hands.

Simultaneous clinical, scintigraphic, and macroradiographic assessments were carried out on 32 patients with hand osteoarthritis and the results at entry and one year reported. The presence and growth of osteophyte correlated with symptoms and a positive scan. The scan did not detect the radiographic features of juxta-articular radiolucencies, subchondral sclerosis, or cartilage thinning. Osteophytes, particularly when fast growing, produce pain, a 'hot' scan, and may predict disintegration of joint architecture.

Osteophytes in the osteoarthritic hand: their incidence, size, distribution, and progression.

Quantitative microfocal radiographic assessment of osteophytes in osteoarthritic hands showed that their number and area were greatest at joint margins, in the dominant hand, in the second and third compared with fourth and fifth phalanges, in the third phalanx, and in the second distal interphalangeal joint respectively. These sites correspond with those for the largest forces exerted in the hand: the dominant side, the finger tripod used in the precision grip, power grip, and pulp-pinch respectively. The greater osteophytosis on the trapezium of the nondominant first carpometacarpal joint was probably related to forces exerted during power grip. Osteophytes increased significantly in number and area during the 18 month study period.

Vestibulocochlear dysfunction in a patient with rheumatoid disease and vasculitis.

The case is described of a patient with rheumatoid disease and evidence of vasculitis who developed acute vestibuloauditory dysfunction resulting in total deafness, which was assumed to be secondary to a vasculitic process affecting the vestibulocochlear nerve. Treatment of the underlying vasculitic process, despite effecting a general improvement of the patient's rheumatoid disease, did not significantly improve the auditory dysfunction.

Anterolateral rupture of popliteal cysts in rheumatoid arthritis.

Popliteal cysts occur commonly in both normal and arthritic knees. Most cysts are formed by distension of the medially situated semimembranosus bursa. Popliteus bursa distension occurs uncommonly as a lateral popliteal cyst. Two cases of rupture of lateral cysts which produced symptoms related to the anterolateral lower leg are reported. The difficulty of diagnosing the condition because of this unusual site of inflammation and subsequent management problems are discussed.

Techetium 99m methylene diphosphonate bone scanning in osteoarthritic hands.

In this prospective study, the radiological features characteristic of osteoarthritis of the hand were compared with the radionuclide bone scan images. A total of 32 patients was assessed at 6-monthly intervals for 18 months. Microfocal radiographs were taken at each visit. The high magnification and resolution of this technique permitted direct measurement of joint space width, subchondral sclerosis, osteophyte number and area and juxta-articular radiolucency area for each joint in the hand. Four-hour technetium 99m methylene diphosphonate bone scans were taken at 0 and 12 months and the activity of tracer uptake at each joint scored. The latter was compared with each X-radiographic feature at every visit and the changes between visits analysed. The scan scores did not correlate with any of the X-radiographic features other than osteophyte size. During the study the size of growing and remodelling osteophytes increased significantly at joints with raised or increased isotope uptake.

Association of osteoarthritis with homozygosity for a 5.8 kb Taq I fragment of the alpha 1-antichymotrypsin gene.

The genes coding for the protease inhibitors alpha 1-antitrypsin (A1AT) and alpha 1-antichymotrypsin (A1ACT) were analysed by Southern blot in patients with rheumatoid arthritis, psoriatic arthritis, psoriasis without arthritis, polymyalgia rheumatica and generalized osteoarthritis. The probe/restriction enzyme combinations used were the 4.6 kb 5' fragment of the A1AT gene with the Sst I enzyme, the 6.5 kb 3' fragment of the same gene with Taq I and the 3.4 kb fragment of A1ACT with Taq I. The frequency of homozygous genotype for the 5.8 kb A1ACT band was increased in osteoarthritis (62.8% versus 36.8%, P = 0.01, relative risk = 2.9, aetiological fraction = 0.41). No other disease association was found with any marker. This suggests that the A1ACT gene may influence susceptibility to generalized osteoarthritis.

A controlled trial of sulphasalazine treatment of chronic ankylosing spondylitis: failure to demonstrate a clinical effect.

Sixty-two patients with long established but symptomatic ankylosing spondylitis were treated with sulphasalazine or matching placebo in a randomized double-blind controlled trial for 48 weeks. There were no consistent significant differences between the treatment groups in clinical parameters despite multiple assessments. Equivalent numbers in each group were able to decrease or stop non-steroidal anti-inflammatory drug ingestion during the study period (four active, eight placebo). Side effects were reported more commonly in the sulphasalazine group (27 versus 17, NS), but only 21 patients stopped treatment because of side effects (12 versus 9, NS). Analysis of the subgroup with an initial ESR greater than 20 mm/h failed to show any persisting differences of response between sulphasalazine and placebo. We conclude that sulphasalazine therapy does not have a role in the treatment of chronic ankylosing spondylitis.

Quantitative microfocal radiographic assessment of progression in osteoarthritis of the hand.

We studied 32 patients with osteoarthritis who had 5x macroradiographs taken of their wrists and hands at 6-month intervals over an 18-month period. The higher magnification and resolution of microfocal radiography permitted the quantitative detection of progressive changes in 4 different features: subchondral sclerosis, the number and size of osteophytes, juxtaarticular radiolucencies, and joint space narrowing. Compared with normal control subjects, subchondral cortical thickness was greater in all patients at entry and showed a variable degree of change over the study period. Osteophytes and juxtaarticular radiolucencies were present in all patients at study entry; by the end of the study, osteophytes had increased in number and area, and juxtaarticular radiolucencies had increased in area, but not in number. At entry, 44% of the patients had joint space narrowing significantly greater than that in the control subjects; by 18 months, this proportion increased to 65%. No correlation was found between subchondral sclerosis, osteophytes, juxtaarticular radiolucencies, and joint space narrowing. We conclude that in osteoarthritis of the hand, the bony changes have progressed significantly before the occurrence of radiographically evident joint space narrowing indicative of cartilage thinning.