Osteoarthritis of the hip: agreement between joint space width measurements on standing and supine conventional radiographs

OBJECTIVE: To assess the effect of standing position on joint space width (JSW) measurements of the hips with and without osteoarthritis (OA) on pelvic radiographs. METHODS: Adult patients aged 18 or more had pelvic anteroposterior conventional radiographs standing and supine performed by a single radiologist in the same radiology unit according to standardised guidelines. JSW measurements in mm were made by a single reader blind to patients' identity and type of view, using a 0.1 mm graduated magnifying glass directly laid over the radiograph, at the narrowest point for OA hips or at the vertical joint space for non-OA hips. Agreement of JSW between both views was assessed using the Bland and Altman graphical analysis. RESULTS: JSW was greater on standing than supine radiographs, for example, 7.1% for OA hips. Mean (SD) differences and limits of agreement (mm) between both views were 0.08 (0.27) and -0.46 to 0.62 for the 70 non-OA hips, 0.02 (0.31) and -0.60 to 0.64 for the 46 OA hips. Corresponding 95% confidence intervals of mean difference were 0.02, -0.14 mm and -0.07, -0.11 mm. CONCLUSIONS: Measurements of JSW of the hip on pelvic standing and supine radiographs are concordant. Changes less than or equal to 0.64 mm between the two views are similar or inferior to radiological progression of OA.     

Quantitative measurement of joint space narrowing progression in hip osteoarthritis: a longitudinal retrospective study of patients treated by total hip arthroplasty

OBJECTIVES: To evaluate the rate of progression of radiological joint space narrowing (JSN) in patients operated on for hip osteoarthritis (OA) and to determine its predictive factors. METHODS: Study design: retrospective longitudinal trial of 61 patients who underwent total hip arthroplasty (THA) for hip OA (69 operated hips). Mean follow-up 81.2 +/- 9.9 months. Collected data: (1) standing frontal radiographs of the pelvis from diagnosis to surgery (246 films) for morphological evaluation and quantitative measurement of joint space width (JSW) (computerized reading of digitized X-rays); (2) demographic data (sex, age, body mass index, smoking status, professional and sporting activities, family history of OA); (3) clinical data (age at onset-diagnosis and THA, drug consumption, time from diagnosis to permanent disability, OA at other joints, previous THA of the contralateral hip). Statistics: multivariate analysis. RESULTS: The yearly mean narrowing (YMN) of MeanJSW was 0.43 +/- 0.43 mm/yr (median 0.29, range 0.03-2.55). YMN correlated inversely with joint space width at operation and follow-up duration, and was increased in atrophic OA (r = 0.71). The time between diagnosis and THA correlated with JSW at diagnosis, and was inversely correlated with age at onset and YMN. It was longer in patients with hypertrophic OA (r = 0.69). CONCLUSION: Rapid progression of JSN, older age and absence of osteophytes appear to be the main factors leading to THA.     

Pathogenesis of Alzheimer-related neuritic plaques: AT8 immunoreactive dystrophic neurites precede argyrophilic neurites in plaques of the entorhinal region, hippocampal formation, and amygdala

We examined the reliability of the anteroposterior and posterior condylar axes for determining rotational alignment of the femoral component in total knee arthroplasty (TKA). A computed tomography scan was taken at the level of the femoral epicondyle in 84 knees (27 varus knees with medial femorotibial arthritis (FT-OA) in 26 patients, 17 knees with patellofemoral arthritis in 14 patients, and 40 normal knees in 40 volunteers). On the image, an anteroposterior axis, a line perpendicular to the anteroposterior axis, an epicondylar axis and a posterior condylar axis were drawn, and the relationship between the three axes was assessed. The mean values for the 84 knees were evaluated, and the posterior condylar axis was 6.0 degrees +/- 2.4 degrees internally rotated relative to the epicondylar axis, while the line perpendicular to the anteroposterior axis was 1.4 degrees +/- 3.3 degrees internally rotated relative to the epicondylar axis. The internal rotation angle of the posterior condylar axis relative to the epicondylar axis was 6.2 degrees +/- 1.9 degrees in the knees with medial femorotibial arthritis, 6.4 degrees +/- 2.4 degrees in the knees with patellofemoral arthritis, and 5.8 degrees +/- 2.7 degrees in the normal knees, showing consistent values in normal and osteoarthritic knees. The internal rotation angle of the line perpendicular to the anteroposterior axis relative to the epicondylar axis was 0.1 degrees +/- 3.3 degrees, 1.3 degrees +/- 3. 3 degrees, and 2.3 degrees +/- 3.1 degrees in the three groups, respectively (i.e., there were significant differences between the medial FT-OA knees and the normal knees). The results demonstrated that the anteroposterior axis was rotated externally to a significant degree in medial FT-OA knees and was less reliable than the posterior condylar axis for use in alignment for TKA on medial FT-OA knees.     

The effect of wedged insoles on the thrust of osteoarthritic knees

We describe a method of quantifying the lateral/medial thrust of the knee which occurs in the early phase of walking. We have used this method to evaluate the effects of wedged insoles on the lateral and medial thrust for normal knees and knees with unicompartment osteoarthritis (OA). A laterally elevated (valgus) insole decreased the lateral thrust of both normal and osteoarthritic knees. A medially elevated (varus) insole increased the lateral thrust. In 50 symptomatic knees with medial compartment OA, decreasing the lateral thrust with a valgus insole reduced pain on walking in 27. Patients whose pain was reduced by valgus insoles tended to have earlier OA and to have a significantly greater reduction in the lateral thrust than in the 23 remaining unaffected knees. A varus insole was effective in decreasing the medial thrust and reducing pain in all ten knees with lateral compartment OA. We recommend the use of valgus insoles for patients with painful early medial compartment OA and the use of varus insoles for lateral compartment OA.     

Joint loading with valgus bracing in patients with varus gonarthrosis

The purpose of this study was to determine whether a brace designed to unload varus degenerative knees actually alters medial compartment loads by decreasing the adduction moment. Eleven patients who had arthrosis confined to the medial compartment were fitted with a valgus brace and tested before and after brace wear with pain and function scoring instruments and by automated gait analysis. The biomechanical data from these patients were compared with those from 11 healthy control subjects. Scores from an analog pain scale decreased 48% with brace wear, and function with activities of daily living increased 79%. Mean adduction moment without the brace measured 4.0 +/- 0.8% body weight times height versus 3.6 +/- 0.8% body weight times height when wearing the brace (10% decrease). The mean adduction moment for control subjects was 3.5 +/- 0.6% body weight times height. Thus, the mean adduction moment decreased from approximately one standard deviation from the normal mean to a value that is similar to the control value. Nine of 11 patients had a decrease in the adduction moment with the brace, five of 11 patients had a reduction higher than 10%, and decreases in this moment were as high as 32%. This study shows that pain, function, and biomechanical knee loading can be altered by a brace designed to unload the medial compartment of the knee.     

Management of ductal carcinoma in situ of the breast

The natural course of primary osteoarthritis of the knee with or without treatment by intraarticular corticosteroid injections was investigated in 446 patients presenting from 1970 to 1973. Sixty-one of these patients were able to be followed up in 1982 and were divided into two groups. One group included 53 patients (82 knees) without corticosteroid injections. The other group had eight patients (14 knees) who received intraarticular steroids (mean number of injections: 25; range:4-78). The standing femorotibial angle at followup in the male patients receiving injections (p < 0.05) was four degrees of greater varus angulation. Radiographic degeneration was more advanced in 11 of the 24 steroid-treated knees (78.6%), and in 43 of the 82 knees without steroid injections (52.4%) (p < 0.01).     

Osteoarthritis of limbs in hospital practice in Lomé (Togo)

Medical records of patients seen at the Lomé Teaching Hospital rheumatology clinic (Togo) were studied retrospectively to determine the prevalence and topographic patterns of osteoarthritis. Among the 2626 patients seen over a three-year period, 232 had appendicular osteoarthritis. Distribution of affected joints was as follows: knee, 212 patients (83% female, 17% male); hip, 17 patients with primary osteoarthritis; scapulohumeral joint, 2 patients; and fingers, 1 patient. At the knee, the lesions involved the medial femorotibial compartment in 114 patients, the lateral femorotibial compartment in 54 patients and the patellofemoral compartment in 44 patients. Mean age at onset of femorotibial osteoarthritis was 50 years. Among females with femorotibial osteoarthritis, 70% were obese and 90% had varus or valgus deformities. This study confirms that in black Africa the high prevalence of femorotibial osteoarthritis contrasts with the low prevalence of primary osteoarthritis of the hip and of osteoarthritis of the fingers. Female sex, obesity, and varus or valgus deformities are the main risk factors for femorotibial osteoarthritis in black Africa.     

Electromyographic findings in muscles around the osteoarthritic knee: integrated electromyography and frequency analysis

An evaluation of the muscular functions of the vastus medialis, vastus lateralis, rectus femoris, medial hamstring, and of the lateral hamstring was performed using electromyography in 33 knees of 26 female patients with osteoarthritis (OA group) and in 25 knees of 19 healthy female volunteers (control group). During standing on both feet, all muscles in the OA group showed higher IEMG (integrated electromyography) and higher LMR (IEMG of vastus lateralis/IEMG of vastus medialis ratio in the quadriceps; and lateral hamstring/medial hamstring ratio in the hamstrings) than the control group. These augmentary muscular activities ameliorated the varus deformity caused by the osteoarthritis. During maximum isometric voluntary contraction, the OA group showed lower extension and flexion torque of the knees and also lower IEMG than to the control group, while the IEMG of vastus lateralis was not lower. These findings indicated decreased muscular activities in the osteoarthritic knee, and that the activity of the quadriceps was maintained mainly by the vastus lateralis under such conditions. Frequency analysis of the myoelectric signal during maximum isometric voluntary contraction revealed a single peak of low frequency in the power spectrum density function of the quadriceps and double peaks of low and of high frequency in the hamstring. In the OA group, the peak height of the low frequency component was increased in the quadriceps and decreased in the hamstring. We concluded that the duration of the motor unit action potentials was affected in the osteoarthritic knee.     

MRI of the intracerebral lesions at 0.5 Tesla: comparison of fast spin-echo and conventional spin-echo sequences

The purpose of this study was to identify the angiosome of the medial saphenous artery and vein and to evaluate the use of this cutaneous angiosome as a free skin flap in the dog. In phase 1 of this study, selective angiography of the medial saphenous artery performed in six canine cadavers showed that the skin covering the entire medial femorotibial area, the distal half of the caudal head of the sartorius muscle, and the gracilis muscle were perfused by the medial saphenous artery. In phase 2, a medial saphenous fasciocutaneous island flap was raised and sutured back to the skin edges of the donor wound in three dogs. One hundred percent survival of all of the flaps occurred. In phase 3, a medial saphenous fasciocutaneous microvascular free flap was transferred to a wound that was created over the dorsal metacarpal (n = 3) or metatarsal region (n = 3). The mean length +/- SD of the medial saphenous vascular pedicle was 80 +/- 13 mm (n = 5); the mean diameter +/- SD of the medial saphenous artery was 2.8 +/- 0.2 mm (n = 5) and the mean diameter +/- SD of the medial saphenous vein was 4.2 +/- 0.2 mm (n = 5). One hundred percent of all flaps survived (n = 6). Selective angiography or the distal cranial tibial artery (metatarsal wounds, n = 3) and the median artery (metacarpal wound, n = 3) was performed 3 weeks after surgery. All of the vascular anastomoses were patent and neovascularization of the wound beds was present. This free flap was found to be acceptable for cosmetic reconstruction of wounds located on the distal extremity.     

Periosteal new bone formation in a canine neuropathic model of osteoarthritis

OBJECTIVE: To characterize, for the first time, periosteal new bone formation in a well-established canine model of accelerated osteoarthritis (OA) with features of neuropathic arthropathy. METHODS: Seven dogs underwent left L4-S1 dorsal root ganglionectomy (DRG), followed 3 weeks later by transection of the anterior cruciate ligament of the ipsilateral knee (ACLT). Eight weeks thereafter, a postmortem examination was performed to assess the severity of cartilage changes of OA and the formation of new bone on the distal femur and proximal tibia in the cruciate-deficient limb. RESULTS: As described previously, extensive full-thickness ulceration of the articular cartilage was present in the unstable knee of every dog. The femoral shaft immediately proximal to the condyles in the unstable limb was consistently wider (mean +/- SD diameter 22.4 +/- 2.2 mm) than that in the contralateral limb (19.9 +/- 1.3 mm; P = 0.01). Xeroradiography and histologic examination of the distal femur revealed extensive formation of woven bone on the periosteal surfaces of the medial, lateral, and anterior aspects of the femoral shaft in the OA limb of every dog. These bony changes were not seen in radiographs of dogs that underwent DRG with the cruciate ligament left intact (n = 8) or of neurologically intact dogs that underwent ACLT (n = 7) and were examined 24 weeks after surgery. CONCLUSION: Formation of new periosteal bone on the distal femur and tibia is a feature of this model of accelerated OA that is not seen in the conventional ACLT model of OA in the neurologically intact dog. This observation suggests that interruption of sensory input from the limb may affect the regulation of osteogenesis in the mechanically unstable joint.     

Knee adduction moment, serum hyaluronan level, and disease severity in medial tibiofemoral osteoarthritis

OBJECTIVE: The adduction moment at the knee during gait is the primary determinant of medial-to-lateral load distribution. If the adduction moment contributes to progression of osteoarthritis (OA), then patients with advanced medial tibiofemoral OA should have higher adduction moments. The present study was undertaken to investigate the hypothesis that the adduction moment normalized for weight and height is associated with medial tibiofemoral OA disease severity after controlling for age, sex, and pain level, and to examine the correlation of serum hyaluronan (HA) level with disease severity and with the adduction moment in a subset of patients. METHODS: Fifty-four patients with medial tibiofemoral OA underwent gait analysis and radiographic evaluation. Disease severity was assessed using the Kellgren-Lawrence (K-L) grade and medial joint space width. In a subset of 23 patients with available sera, HA was quantified by sandwich enzyme-linked immunosorbent assay. Pearson correlations, a random effects model, and multivariate regression models were used. RESULTS: The adduction moment correlated with the K-L grade in the left and right knees (r = 0.68 and r = 0.60, respectively), and with joint space width in the left and right knees (r = -0.45 and r = -0.47, respectively). The relationship persisted after controlling for age, sex, and severity of pain. The partial correlation between K-L grade and adduction moment was 0.71 in the left knees and 0.61 in the right knees. For every 1.0-unit increase in adduction moment, there was a 0.63-mm decrease in joint space width. In the subset of patients in whom serum HA levels were measured, HA levels correlated with medial joint space width (r = -0.55), but not with the adduction moment. CONCLUSION: There is a significant relationship between the adduction moment and OA disease severity. Serum HA levels correlate with joint space width but not with the adduction moment. Longitudinal studies will be necessary to determine the contribution of the adduction moment, and its contribution in conjunction with metabolic markers, to progression of medial tibiofemoral OA.     

Histomorphological and immunohistochemical evaluation of joint changes in a model of osteoarthritis induced by lateral meniscectomy in sheep

OBJECTIVE: To evaluate the histomorphological and immunohistochemical changes induced in cartilages of ovine stifle (knee) joints 6 months after unilateral lateral meniscectomy. METHODS: Osteochondral sections were obtained from 8 distinct regions of knee joints of 6 adult Merino wethers that 6 months earlier had undergone lateral meniscectomy. Joint regions of 6 age matched sheep housed under identical conditions were used for controls. Serial sections were stained with toluidine blue or immunolocalized with monoclonal antibodies (Mab) 3B3(-), 7D4, and 5B10, which recognize epitopes on proteoglycans. RESULTS: In control joints the cartilage from the region of the tibial plateau not protected by the meniscus had significantly (p < 0.005) more structural abnormalities than other joint regions. After meniscectomy, only cartilages in the lateral femorotibial compartment showed histomorphological changes consistent with osteoarthritis (OA). The nature and severity of the lesions differed between the topographical regions within the joint. The most severe were found on the lateral femoral condyles and tibial plateaus. Reactivity with Mab 3B3(-), 7D4, and 5B10 was increased only in the lateral compartment cartilages, and was stronger in mild rather than moderate OA. CONCLUSION: Six month lateral meniscectomy in sheep produces histomorphological and immunohistochemical cartilage changes analogous to those described for early human OA and in other animal models. The severity and type of lesions obtained were dependent on the topographical joint location, but were most evident in cartilages from the lateral compartment.     

Further characterization of the syndrome of right bundle branch block, ST segment elevation, and sudden cardiac death

There is a lack of defined reference points for reproducible femoral tunnel placement during posterior cruciate ligament (PCL) reconstruction. The PCL, consisting of two major bands, anterolateral (AL) and posteromedial (PM), has a femoral origin that spans 3 cm, which cannot be covered by a substitute graft positioned in one femoral tunnel to reconstruct the PCL. The purpose of this study was to define the location of the anatomic origin of both bands of the PCL in reference to local anatomy to develop landmarks that can be used to reproducibly position two femoral tunnels (one to each band's origin) during PCL reconstruction. The anatomy of the PCL origin was dissected and studied in 20 knees at the time of total knee replacement. The central origin point for each band was marked, and its distance was measured in reference to three axes. The AL band centrally originated 13 +/- 0.5 mm posterior to the medial articular cartilage-intercondylar wall interface and 13 +/- 0.5 mm inferior to the articular cartilage-intercondylar roof interface. The PM band centrally originated 8 +/- 0.5 mm posterior to the medial articular cartilage-intercondylar wall interface and 20 +/- 0.5 mm inferior to the articular cartilage-intercondylar roof interface. These distances were noted to be relatively constant despite varying knee morphologies and size. For this reason, referencing the articular cartilage-intercondylar roof, and wall interfaces may be used as a method to facilitate more reproducible anatomic femoral tunnel placements during PCL reconstruction.     

Relationship between gait and clinical results after high tibial osteotomy

Thirty-two patients with primary osteoarthritis of the medial compartment of the knee were studied prospectively to assess the relationship between clinical results, limb alignment, and adduction moment of the knee. Clinical and radiographic examination and gait analyses were performed preoperatively and repeated at 6 months and at 1, 3, and 6 years after high tibial osteotomy. The preoperative peak adduction moment was high in 25 patients and low in seven. In both groups, the adduction moment of the knee decreased at 6 months after surgery but increased after that period. Alignment of the affected knee in both groups remained valgus after surgery (average femorotibial angle, 167 degrees-169 degrees). Clinical outcome in both groups improved after surgery and remained unchanged after 1 year. The peak adduction moment of the knee for the whole group significantly correlated with alignment and foot angle before and 6 years after surgery but did not correlate with stride length and walking velocity. In addition, only alignment was associated significantly with clinical results at 6 years. These results suggest that the preoperative peak adduction moment of the knee does not correlate with clinical or radiographic outcomes of high tibial osteotomy, provided sufficient valgus alignment is achieved at surgery.     

How can and do Australian doctors promote physical activity?

We describe a modified technique for the salvage of a total knee arthroplasty after disruption of the extensor mechanism. Between January and December 1992, seven patients had reconstruction of the extensor mechanism with use of a medial or an extended medial gastrocnemius flap. Six of the seven patients were followed for a mean of thirty-three months (range, twenty-six to forty-one months) and were evaluated both preoperatively and postoperatively with regard to the knee and functional scores of The Knee Society as well as the range of motion, extensor lag, walking status, and patellar height. The seventh patient was lost to follow-up six months postoperatively and was excluded from the analysis of the results. Preoperatively, the knee and functional scores were 16 +/- 12.3 points and 12 +/- 12.1 points (mean and standard deviation), respectively; the mean range of motion was 70 +/- 44.0 degrees; and the mean extensor lag was 53 +/- 33.4 degrees. Postoperatively, the mean knee and functional scores improved to 82 +/- 12.4 points and 51 +/- 23.0 points, respectively; the mean range of motion improved to 100 +/- 21.8 degrees; and the mean extensor lag decreased to 24 +/- 18.8 degrees. After the procedure, all patients who previously had been dependent on a walker were able to walk about the community with or without a cane, and those who had been dependent on a wheelchair were able to walk with the assistance of a walker. Patellar height was measured according to the method of Insall and Salvati for the four patients who had a patella. Preoperatively, the patellar heights were grossly abnormal; postoperatively, they more closely approached accepted normal values for three of the four patients. Reconstruction of a complicated rupture of the extensor mechanism with use of a medial gastrocnemius transposition flap after total knee arthroplasty is a reliable option for treatment.     

Femoral condyle geometry in the normal and varus knee

Femoral condyle geometry was evaluated in 30 normal and 30 varus knees using magnetic resonance imaging. In the sagittal view, the distal part of the medial condyle was deformed in the varus knees, but there was no significant difference in the posterior part of the medial condyle between the normal and varus knees. In the transverse view, the transepicondylar axis (a reliable rotational landmark) showed approximately 6 degrees external rotation relative to the posterior condylar axis in the varus knees and the normal knees. The results of this study suggest that no hypoplasia exists at the posterior part of the medial condyle in varus knees. In addition, the posterior condylar axis may be a reliable rotational landmark but is in relative internal rotation in varus knees when total knee arthroplasty is performed.     

In vivo anteroposterior femorotibial translation of total knee arthroplasty: a multicenter analysis

A study was conducted to determine in vivo femorotibial contact patterns for subjects having a posterior cruciate retaining or posterior cruciate substituting total knee arthroplasty. Femorotibial contact of 72 subjects implanted with a total knee replacement, performed by five surgeons, was analyzed using video fluoroscopy. Thirty-one subjects were implanted with a posterior cruciate retaining total knee replacement with a flat polyethylene posterior lipped insert, 12 with a posterior cruciate retaining total knee replacement with a curved insert, and 29 with a posterior cruciate substituting total knee replacement. Each subject performed successive deep knee bends to maximum flexion. Video images at 0 degree, 30 degrees, 60 degrees, and 90 degrees flexion were downloaded onto a workstation computer. Femorotibial contact paths were determined for the medial and lateral condyles using an interactive model fitting technique. Femorotibial contact anterior to the tibial midline in the sagittal plane was denoted as positive and contact posterior was denoted as negative. Analysis of average femorotibial contact pathways of both posterior cruciate retaining designs revealed posterior femorotibial contact in full extension with anterior translation of femorotibial contact commonly observed in midflexion and terminal flexion. In posterior cruciate substituting designs, anterior femoral translation was seen medially at 30 degrees to 60 degrees flexion but rarely was observed laterally. Posterior femoral rollback laterally from full extension to 90 degrees flexion was seen in 100% of subjects implanted with a posterior cruciate substituting total knee replacement, versus 51.6% (posterior lipped polyethylene insert) and 58.3% (curved insert) of those with a posterior cruciate retaining total knee replacement. Data from this multicenter study are remarkably similar to previous fluoroscopy data from a single surgeon series, showing a lack of customary posterior femoral rollback in both posterior cruciate retaining designs, and conversely showing an average anterior femoral translation with knee flexion. Posterior femoral rollback, less than in normal knees, routinely was observed in posterior cruciate substituting total knee arthroplasty, attributed to engagement of the femoral component cam with the tibial post. The abnormal anterior femoral translation observed in posterior cruciate retaining total knee arthroplasty may be a factor in premature polyethylene wear observed in retrieval studies.     

Radiographic patterns and associations of osteoarthritis of the knee in patients referred to hospital

OBJECTIVES: To investigate differing patterns and associations of osteoarthritis of the knee in patients referred to hospital. METHODS: Two hundred and fifty two consecutive patients (161 women, 91 men; mean age 70 years, range 34-91 years) referred to hospital with osteoarthritis of the knee underwent clinical, radiographic, and synovial fluid screening. RESULTS: Radiographic changes of osteoarthritis of the knee (definite narrowing with or without osteoarthritic features) were bilateral in 85% of patients. Of 470 knees affected, 277 (59%) were affected in two compartments and 28 (6%) in three compartments. Unilateral and isolated medial tibiofemoral osteoarthritis were more common in men. Calcium pyrophosphate crystal deposition was common (synovial fluid identification in 132 (28%) knees; knee chondrocalcinosis in 76 (30%) patients) and associated with disability, bilateral, multicompartmental and severe radiographic osteoarthritis, marked osteophytosis, attrition, and cysts. Multiple clinical nodes (58 (23%) patients) and radiographic polyarticular interphalangeal osteoarthritis (66 (26%) patients) were associated with a higher frequency of inactivity pain, disability, multicompartmental and severe radiographic change. Forestier's disease predominated in men but showed no other associations. CONCLUSIONS: In a group of patients referred to hospital osteoarthritis of the knee is usually bilateral and affects more than one compartment. Severe and multicompartmental radiographic changes are associated with calcium pyrophosphate crystal deposition, nodal change, and polyarticular interphalangeal osteoarthritis.     

The effects of high-dose methotrexate on the development of cartilage lesions in a lapine model of osteoarthrosis

To determine whether systemic administration of methotrexate (MTX) can prevent joint destruction in experimental osteoarthrosis (OA) in rabbits, the disorder was induced unilaterally in the knee joints of 40 rabbits by partial medial meniscectomy and sectioning of the medial collateral and both cruciate ligaments. A sham operation (arthrotomy only) was performed in another four animals. Effects on the cartilage of the femoral condyles were studied after 6 and 12 weeks. Twelve weeks after induction, femoral and tibial osteophyte formation was demonstrated on radiographs in all cases. Marked cartilage damage was found histologically (median Mankin score 10 vs 1 for non-operated controls; P < 0.05, Wilcoxon test). Cartilage proteoglycan (GAG) content (dye binding assay) was reduced in operated joints [63 +/- 8 (mean +/- SEM) vs 75 +/- 6 micrograms chondroitin sulfate/mg cartilage wet weight], and the leukocyte count in the joints was elevated (226 +/- 14 vs 7 +/- 3 leukocytes per microliter joint aspirate after injection of 0.5 ml saline solution; both P < 0.05, Wilcoxon test). The rate of GAG synthesis was unchanged (ex vivo labelling with 35S-sulfate). Treatment with MTX (30 mg x kg body weight-1 x week-1 i.m., starting 12 h postoperatively) reduced cartilage damage (median Mankin score 8 vs 10 for placebo, P < 0.05, Mann-Whitney U-test), but had no significant effect on the other parameters tested. No significant MTX effects were observed on cartilage from nonoperated joints. Our data indicate that MTX may have a limited therapeutic effect in experimental OA in the rabbit.     

Verrucous carcinoma of the penis

Thirty-four patients with osteoarthritis (OA) and 32 patients with rheumatoid arthritis (RA) were studied to determine the effects of OA and RA on the laxity of the knee joints. Laxity was measured with the Genucom Knee Analysis System. The antero-posterior laxity of the OA and RA knees was greater than the control, normal knees in the early stage, and decreased with the severity of disease in OA, but not in RA. Severe OA and RA were associated with a restricted internal-external rotation at the knee joint compared with the control. Internal-external rotation decreased with worsening of both diseases. Varus-valgus laxity tended to increase slightly with the severity of disease. While the morphological changes of the cruciate ligaments in advanced OA and RA were not statistically different, the laxity of OA-afflicted knees was affected slightly by the severity of the damage to the cruciate ligaments.