Behçet's disease with severe destructive arthritis

Abstract Behçet's disease is a systemic disease characterized by oral aphta, genital ulcers, and ocular lesions, and arthritic manifestations also appear to be common. However, this disease rarely produces loss of function or deformity in arthritic joints. We report the case of a 52-year-old woman with Behçet's disease who had a history of recurrent oral aphta, genital ulcerations, and intestinal lesions for almost 30 years. When she was about 30 years old, she began to notice significant morning stiffness and polyarthritis, and progressive destructive arthritic changes in the bilateral fingers, wrists, and left ankle. Behçet's disease with severe destructive arthritic changes is rare, and the underlying mechanism is still unknown.

In vivo deep-flexion kinematics in patients with posterior-cruciate retaining and anterior-cruciate substituting total knee arthroplasty

BACKGROUND

Posterior-cruciate ligament retaining total knee arthroplasty designs have long been used with excellent clinical success, but often have shown kinematics and flexion performance that are significantly different from the natural knee. The purpose of this study was to compare deep-flexion knee kinematics in patients with two types of posterior-cruciate ligament retaining total knee arthroplasty.

METHODS

One group received a traditional curved symmetric articular configuration, and one group received a design incorporating a lateral compartment which constrains the lateral condyle to the antero-posterior center of the tibial plateau in extension, but allows translation in flexion--roughly approximating the role of the anterior cruciate ligament. In vivo kinematics were analyzed using three-dimensional model registration and plain radiographs of kneeling and squatting activities in 20 knees in 18 patients.

FINDINGS

Knees with the anterior cruciate ligament substituting design exhibited greater flexion, femoral antero-posterior translation and tibial internal rotation.

INTERPRETATION

Geometric features intended to improve knee flexion, including greater antero-posterior stability, a more posterior tibial sulcus, and reshaped femoral condyles, do provide measurable and significant differences in deep-flexion knee kinematics.

A role for the aryl hydrocarbon receptor and the dioxin TCDD in rheumatoid arthritis

OBJECTIVE

Environmental factors are involved in RA pathogenesis and epidemiological studies have suggested that smoking is an environmental risk factor for RA. The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is one of the major toxic components in cigarettes. To clarify the biological effects of smoking in RA, we investigated the role of TCDD in RA pathogenesis.

METHODS

Human synovial tissue was obtained from RA and OA patients and aryl hydrocarbon receptor (AhR) expression in these tissues was evaluated using immunohistochemistry and real-time PCR. Expression of various cytokines was measured by real-time PCR following stimulation of RA synoviocytes with different concentrations of TCDD. To study the role of AhR, we treated RA synoviocytes with alpha-naphthoflavone, a known AhR antagonist. To evaluate which signal transduction pathways were stimulated by the TCDD-AhR interaction, we used inhibitors of nuclear factor-kappaB (NF-kappaB) and extra-cellular stimulus-activated kinase (ERK).

RESULTS

Higher AhR mRNA and protein levels were observed in RA synovial tissue than in OA tissue. TCDD up-regulated the expression of IL-1beta, IL-6 and IL-8 through binding to AhR, and this effect was transmitted via the NF-kappaB and ERK signalling cascades. AhR expression in synovial cells was up-regulated by TNF-alpha.

CONCLUSION

TNF-alpha activates AhR expression in RA synovial tissue, and that cigarette smoking and exposure to TCDD enhances RA inflammatory processes. TCDD induces inflammatory cytokines via its association with AhR, resulting in stimulation of the NF-kappaB and ERK signalling cascades. Thus TCDD exposure, such as smoking exacerbates RA pathophysiology.

Low disease activity state with corticosteroid may not represent 'true' low disease activity state in patients with rheumatoid arthritis

OBJECTIVE

Corticosteroids constitute one of the most common treatments of RA. The purpose of this study is to investigate whether long-term corticosteroid use suppresses the progression of disability in RA patients with low disease activity state.

METHODS

Data collected from a large observational cohort of RA patients at our institution were analysed for 214 RA patients whose disease activity score (DAS) 28 and HAQ were available consecutively from October 2000 to October 2004. All 214 patients had average DAS 28 <3.2, meaning only those who had well-controlled RA disease activity were chosen as subjects. The subjects were divided into steroid users who received continuous corticosteroids every month and non-steroid users who did not receive consecutive corticosteroids continuously every month.

RESULTS

Fifty-five patients (25.7%) were corticosteroid users and 159 (74.3%) were non-users. Average prednisolone for the former group was 4.2 mg/day. No significant differences were observed among baseline variables and RA disease activity variables. However, for steroid users, HAQ progressively worsened with time and for non-steroid users, HAQ progressively improved.

CONCLUSIONS

Although DAS 28 and other variables may suggest well-controlled RA disease activity, functional capacity of patients on low-dose corticosteroids deteriorated. Thus, low disease activity state with corticosteroid may not represent the 'true' low disease activity state. Along with the achievement of a low disease activity state, long-term efficacy, prognosis, and the quality of remission need to be also considered in the tight control of RA activity.

Efficient management of rheumatoid arthritis significantly reduces long-term functional disability

OBJECTIVES

The aim of this study was to examine the effect of efficient management of rheumatoid arthritis (RA) in relation to disability levels in a large cohort of patients with RA over a period of 3 years.

METHODS

We studied 2775 patients with RA who had continuous enrolment for at least 3 years from 7511 patients with RA enrolled in an observational cohort study (Institute of Rheumatology, Rheumatoid Arthritis (IORRA)) from October 2000 to April 2005. The 28-joint Disease Activity Scores (DAS28) were calculated at 6 month intervals for all the patients and a value <2.6 was considered as a tight control. We have set up a new variable for each patient, "Avg-Dscore", based on the transition of each patient's DAS28 value, taking the threshold level of 2.6 into consideration. The "Avg-DAS28" is the average of DAS28 values over all the phases. Functional disability status was assessed by J-HAQ, the validated Japanese version of the Health Assessment Questionnaire (HAQ). The relationship of "Avg-Dscore" and "Avg-DAS28" with the functional disability level was determined using Spearman correlation coefficients and multiple linear regression models.

RESULTS

The baseline features of these 2775 patients were: female 83.7%, mean age 56.8 years, mean RA duration 9.5 years, mean initial DAS28 4.0, mean initial J-HAQ score 0.79, and mean final J-HAQ score 0.86. There was a statistically significant correlation between "Avg-DAS28" and final J-HAQ score (r = 0.57, p<0.001), indicating that tighter disease control has significant association with lower disability levels. A similar relationship was observed between "Avg-Dscore" and final J-HAQ score (r = 0.47, p<0.001). Multiple linear regression analysis, after adjusting for all the covariates, revealed that "Avg-Dscore" and "Avg-DAS28" were the most significant factors contributing to final J-HAQ score, and confirmed the strong relationship between disease activity and functional disability.

CONCLUSIONS

In patients with RA efficient disease management, by maintaining the DAS28 values at a level under 2.6, has significant association with improving functional capability. The threshold DAS28 level of 2.6 may be useful in developing targeted treatment guidelines for patients with RA.

What's in season for rheumatoid arthritis patients? Seasonal fluctuations in disease activity

OBJECTIVES

To examine whether a seasonal fluctuation exists with rheumatoid arthritis (RA) activity and to analyse seasonal effects of varying components that express disease activity in RA patients.

METHODS

A group of 1665 RA patients (mean age 57.2 yrs, mean disease duration 9.9 yrs) whose data were available for 10 consecutive phases from a large observational cohort study conducted at our institution from October 2000 to April 2005, bi-annually, were evaluated. Ten criteria were analysed to assess RA disease activity.

RESULTS

All criteria revealed decrease in disease activity during fall and increase in disease activity during spring, except for the physician's global assessment of disease activity in which significant differences were not observed between the two seasons.

CONCLUSIONS

We found definite seasonal differences in RA patients, both subjectively and objectively. RA disease activity was higher in spring and lower during fall. Seasonal changes may play an important role in evaluating disease activity of RA patients and should be taken into account when examining these patients.

Increased risk of tuberculosis in patients with rheumatoid arthritis in Japan

OBJECTIVE

To determine the risk for tuberculosis infection in patients with rheumatoid arthritis before the anti-cytokine era in Japan.

PATIENTS AND METHODS

A database of a single-institute-based large observational cohort study for rheumatoid arthritis at the Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan, was analysed. Information on the history of tuberculosis infection was collected by patient self-reporting during April and October 2003. The age-adjusted incidence rate and relative risk for tuberculosis infection were investigated.

RESULTS

Among 5044 patients with rheumatoid arthritis, 483 (9.6%) patients claimed to have a history of tuberculosis infection before October 2002. The frequency of history of tuberculosis increased according to the age of the patient. Four cases of new-onset tuberculosis were identified among 5544 patients with rheumatoid arthritis during 1 year. The age-adjusted incidence of tuberculosis was 42.4/100,000 patients. The relative risk for tuberculosis was 3.21 (95% confidence interval (CI) 1.21 to 8.55), and that of men and women was 10.59 (95% CI 3.42 to 32.78) and 1.41 (95% CI 0.2 to 10), respectively.

CONCLUSION

There was an increased risk of tuberculosis infection in Japanese patients with rheumatoid arthritis, especially in male patients before the introduction of anti-tumour necrosis factor treatment. These data should form the basis for the risk management of anti-cytokine treatment in Japan.

Haplotype analysis revealed no association between the PTPN22 gene and RA in a Japanese population

OBJECTIVE

The protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene is a member of the PTPs that negatively regulate T-cell activation. A missense single nucleotide polymorphism (SNP) in the PTPN22 gene known as R620W was recently reported to be associated with several autoimmune diseases including rheumatoid arthritis (RA). The association was confirmed repeatedly in the populations of North European ancestry. However, the SNP was reported to be non-polymorphic in the Asian populations. Because the gene confers an impact on autoimmune diseases, we attempt to explore an association between PTPN22 gene and RA in a Japanese population without restricting to the SNP, R620W.

METHODS

We studied 1128 RA patients and 455 controls. In addition to the SNP, R620W, we selected eight testing SNPs spanning 45 kb over the PTPN22 gene using the International HapMap Project. Genotyping was performed using the TaqMan fluorogenic 5' nuclease assay. Associations between RA and each of the SNPs were estimated by the Fisher's exact test. Haplotype was constructed using the expectation-maximization algorithm.

RESULTS

R620W was not polymorphic enough in both the patients and the controls, and was therefore excluded from further analysis. Each allele frequency for the eight other SNPs in both groups was compared and no association was detected. Haplotype analysis also revealed that PTPN22 gene was not associated with RA in a Japanese population.

CONCLUSION

We found no association between PTPN22 and RA in a Japanese population. The result suggests that the PTPN22 gene is associated with RA only in a specific ethnic group.

Association between PADI4 and rheumatoid arthritis: a meta-analysis

OBJECTIVE

Polymorphisms and haplotypes of the peptidylarginine deiminase type 4 gene (PADI4) have been reported to be associated with rheumatoid arthritis (RA) in a Japanese population. However, subsequent replication studies showed conflicting results. The aim of this study was to determine whether meta-analysis would prove the existence of the association.

METHODS

PubMed was searched using the term 'PADI4' for articles from the publication of the first study to December 2005. Replication studies that tested the association between PADI4 and RA were reviewed for meta-analysis. The Breslow-Day test for homogeneity across the studies was calculated. The Mantel-Haenszel procedure was used to pool odds ratios (OR) with 95% confidence intervals (CI) to evaluate the association.

RESULTS

Six replication studies, one from Japan and five from Europe and North America, fulfilled the selection criteria for inclusion in the meta-analysis. Homogeneity was confirmed across the replication studies. The common OR was 1.14 (95% CI = 1.07-1.21) for allelic distribution. The association was confirmed when only five replication studies in the European descent populations were combined (P = 0.0096, common OR = 1.10).

CONCLUSIONS

Our meta-analysis showed a positive association between PADI4 and RA not only in the Japanese population but also in populations of European descent.

Monocyte chemoattractant protein-4 (MCP-4)/CCL13 is highly expressed in cartilage from patients with rheumatoid arthritis

OBJECTIVES

To study the role of monocyte chemoattractant protein-4 (MCP-4)/CCL13 in the pathogenesis of rheumatoid arthritis (RA), we analysed the expression of MCP-4/CCL13 in chondrocytes, synovial fluid and serum from patients with RA and investigated the effect of MCP-4/CCL13 on the proliferation of synovial cells.

METHODS

Human articular cartilage specimens were obtained from joints from RA and osteoarthritis (OA) patients and normal joints (controls). Transcript levels of MCP-4 in cartilage were determined by real-time polymerase chain reaction. Protein levels were measured by enzyme-linked immunoassay. Cultured fibroblast-like synoviocytes (FLS) were treated with various concentrations of recombinant MCP-4/CCL13 protein, and cell proliferation was evaluated with a viability assay.

RESULTS

The gene expression of MCP-4 was significantly higher in cartilage from RA patients than in that from OA patients (P = 0.00902) and in normal cartilage (P = 0.00902). The concentration of MCP-4/CCL13 protein in serum from RA patients (mean 94.7 +/- 37.6 pg/ml) was significantly higher than in serum from OA patients (mean 49.2 +/- 31.2 pg/ml, P = 0.0051) and controls (mean 32.6 +/- 23.9 pg/ml, P = 0.0001). The concentration of MCP-4/CCL13 protein in synovial fluid from RA patients (mean 247.2 +/- 161.2 pg/ml) was also significantly higher than in that from OA patients (mean 29.6 +/- 50.5 pg/ml, P = 0.000019). Moreover, MCP-4/CCL13 enhanced the proliferation of FLS in a dose-dependent manner.

CONCLUSIONS

MCP-4/CCL13 is highly expressed in RA joints at the mRNA and protein levels. Our results suggest that MCP-4/CCL13 is secreted from chondrocytes and activates the proliferation of rheumatoid synovial cells, thereby leading to joint destruction in RA.

Supportive evidence for a genetic association of the FCRL3 promoter polymorphism with rheumatoid arthritis

BACKGROUND

An association between susceptibility to rheumatoid arthritis and the Fc receptor-like 3 gene (FCRL3) has been reported in a Japanese population. A case-control study showed that the strongest evidence of the association was derived from a polymorphism in the promoter region of FCRL3, which has a regulatory effect on the expression of the gene.

OBJECTIVE

To validate the findings of this previous report by examining the -169C-->T single nucleotide polymorphism (SNP) in a large cohort.

METHODS

752 unrelated cases and 940 controls were genotyped. All the samples were from the same ethnic background as the original study. Genotyping was done using 5' allelic discrimination assays. Association between susceptibility to rheumatoid arthritis and -169C-->T SNP was examined by chi(2) testing.

RESULTS

As in the previous study, the SNP showed significant differences between cases and controls (p = 0.022, odds ratio = 1.18, 95% confidence interval 1.02 to 1.35).

CONCLUSIONS

This result supports a genetic association of the FCRL3 promoter polymorphism with rheumatoid arthritis.

Activated human T cells directly induce osteoclastogenesis from human monocytes: possible role of T cells in bone destruction in rheumatoid arthritis patients

OBJECTIVE

To elucidate the direct role of human T cells in the induction of osteoclastogenesis in rheumatoid arthritis (RA), by studying human monocytes and the pathogenetic roles of receptor activator of nuclear factor kappaB ligand (RANKL), RANK, and osteoprotegerin (OPG).

METHODS

Synovial tissue obtained at total knee replacement was stained immunohistologically using anti-RANKL, CD3, and CD4 antibodies. Synovial fluid was obtained from patients with RA, osteoarthritis (OA), gout, or trauma. Concentrations of the soluble form of RANKL (sRANKL) and OPG in the synovial fluid were measured by enzyme-linked immunosorbent assay. Activated T cells from peripheral blood mononuclear cells (PBMC) of healthy volunteers were cultured with human monocytes from PBMC.

RESULTS

Immunostaining of the synovial tissue of RA patients demonstrated that RANKL-positive cells were detected in a subset of fibroblast-like synoviocytes and infiltrating mononuclear cells. Double immunostaining revealed that RANKL-positive cells were detected in a subset of CD3+ cells and CD4+ cells. An increased concentration of sRANKL and a decreased concentration of OPG were detected in synovial fluid from RA patients. The ratio of the concentration of sRANKL to that of OPG was significantly higher in synovial fluid of RA patients than in synovial fluid of patients with OA or gout. The activated T cells expressing RANKL induced osteoclastogenesis from autologous peripheral monocytes. The role of RANKL in this osteoclastogenetic process was confirmed by dose-dependent inhibition by OPG.

CONCLUSION

The present study is the first to demonstrate osteoclastogenesis using human-derived T cells and monocytes. In addition, the present findings suggest that excess production of RANKL by activated T cells increases the level of sRANKL in synovial fluid and may contribute to osteoclastic bone resorption in RA patients.

[A questionnaire-based survey on the Internet concerning optimal timing for knee surgery in a patient with rheumatoid arthritis]

To investigate the differences between orthopedists and internists in indications for surgical management in patients with rheumatoid arthritis (RA), a questionnaire-based survey was performed on the Internet with the presentation of a case of progressive RA along with serial X-ray films of the knee. Ninety-three doctors (43 orthopedists and 50 internists, average age: 49.2 years) answered the questionnaire. Most of the doctors who viewed the X-ray film showing Larsen's grade IV chose that as the optimal time for total knee arthroplasty. No difference was noted in their choice between orthopedists and internists. Opinions varied widely, however, among younger doctors, but there was agreement among older doctors, suggesting the effect of the study and experience. On the other hand, some doctors recommended arthroscopic synovectomy for knees in the earlier stages of RA, but others did not recommend the arthroscopic surgery itself. Although this new methodology might include possible biases, we believe it should be considered in the research of rheumatology.

[Radiological evaluation of foot deformities in rheumatoid arthritis]

Deformities of the feet are common in patients with rheumatoid arthritis (RA). We investigated whether there was any correlation among forefoot deformities, flat foot or articular destruction of the midfoot and hindfoot, in 146 feet of 73 RA patients whose age varied from 26 to 81 years (mean 58.5 years). In all patients, anteroposterior (AP) and lateral radiographs of the feet with weight bearing were obtained. The hallux valgus angle (HVA), the intermetatarsal angle between the 1st and 2nd metatarsals (M 1 M 2), and the intermetatarsal angle between the 1st and 5th metatarsals (M 1 M 5) were measured on AP radiographs. On slateral radiographs, the height of the arch was measured and articular destruction of the talocalcaneal, talocrural, talonavicular, cuneonavicular and cuneometatarsal joints was measured and classified using Steinbrocker's classification. The average HVA was 23.4 degrees, the average M 1 M 2 was 11.1 degrees, and the average M 1 M 5 was 28.4 degrees. There was no correlation between forefoot deformities and flat foot. There were significant correlations between arthritic destruction of the cuneometatarsal joint and HVA, M 1 M 2 and M 1 M 5. The correlations between arthritic destruction of the cuneonavicular joint and HVA or M 1 M 2 were also significant, although weaker. Thas, we found some relationships between forefoot deformity and arthritics destruction of midfoot joints. Especially, the correlations between arthritic destruction of the cuneonavicular and cuneometatarsal joints and forefoot deformities were significant. Many radiographic methods for the assessment of RA have been reported, however, it is difficult to assess sarthritic destruction of rheumatoid feet with the existing methods. Accordingly, a new method should be established.

Calcium pyrophosphate dihydrate crystal deposition disease after anterior cruciate ligament reconstruction

We report the case of a 34-year-old woman who presented with calcium pyrophosphate dihydrate (CPPD) crystal deposition disease shortly after anterior cruciate ligament (ACL) reconstruction using a polyester artificial ligament (Leeds-Keio; Neoligaments, Leeds, England). The patient had earlier undergone a medial collateral ligament repair of a sprain to her right knee incurred while skiing. Nine years later, she underwent ACL reconstruction. Seventeen months after ACL reconstruction, calcification was observed on radiographs of the medial and lateral menisci. Based on these calcifications and polarized light microscopic findings of the joint fluid, the diagnosis was made of CPPD crystal deposition. CPPD deposition appeared to have resulted from intra-articular damage incurred during ACL reconstruction as well as prolonged anterior instability.

[Bronchospasm due to anaphylactic reaction to Hydroxyethyl starch (HESPANDER)]

A 14-year-old male without any history of allergic disorders developed severe bronchospasm with skin rash 15 min. after the administration of hydroxyethyl starch (HES) during thoratic epidural anesthesia supplemented with N2O-sevoflurane-O2 anesthesia. Aminophylline, hydrocortisone, and epinephrine were administered. These treatments were effective, and the airway pressure was restored to normal ranges within 3 hrs. After the operation, the patient was extubated, because the results of the arterial blood gas examinations recovered to normal ranges. Plasma histamine and complement levels were almost within normal limits, but IgE levels were approximately 5 times higher than normal. Subsequent immediate skin test with hydroxyethyl starch showed an immunologically positive response. These results demonstrate evidence that an anaphylactic reactions could occur just after the start of HES infusion. Severe adverse reactions to HES are very rare, but it is important to keep the possibility always in mind.

Simplification of the Elmslie-Trillat procedure for patellofemoral malalignment. Is medial capsulorraphy necessary?

We describe a modification of the Elmslie-Trillat operation which includes a lateral retinacular release and medial realignment of the tibial tuberosity, but omits medial capsulorraphy. Seventy-five patients were reviewed with a follow up longer than 2 years and the results compared with the conventional Elmslie-Trillat procedure, which consists of lateral release, medial realignment of the tuberosity and medial capsulorraphy. The simpler operation can work as well and the period of rehabilitation is shorter. The incidence of injury to the saphenous nerve is reduced and the cosmetic appearance is more satisfactory. We conclude that medial capsulorraphy is usually unnecessary in this type of procedure.

Histologic and biomechanical characteristics of the supraspinatus tendon: Reference to rotator cuff tearing

A bursal- or joint-side incomplete thickness tearing of the rotator cuff is clinically important, because it is known that this tearing has the potential to develop into a complete tendon disruption. Normal cadaveric supraspinatus tendons were analyzed histologically and biomechanically to clarify the differences in pathomechanical causation of bursal- and joint-side incomplete tears. Histologically, the bursal-side layer was composed of tendon bundles with a decreasing muscular component toward the insertion. The joint-side layer was a complex of tendon, ligament, and joint capsule without transitional areas. Biomechanically, the bursal-side layer had greater deformation and tensile strength. When each layer was divided into three portions of equal length, the middle segment of the bursal-side layer elongated the most, whereas the entire joint-side layer increased evenly in length. We conclude that the joint-side layer is more vulnerable to a tensile load than the bursal-side layer.

[An experimental study on mechanism of cruciate ligament rupture especially on the effect of mechanical property and tensile speed]

Patterns of rupture of the anterior cruciate ligament of the knee are most probably determined by mechanical factors. An experimental study was designed to determine patterns of rupture of the anterior cruciate ligament in immature (young) and fully mature (adult) pig models. Two different methods were used to test disruption forces in young and adult pig knee specimens: quasi-static tension at three different rates using the Instron testing instrument (1000), and impact loading using a specially designed machine. A total of 118 pig test knees was studied. Greater rupture force was required in the adult pigs than in the young pigs. In addition, rupture force was higher with impact loading test than with quasi-static tensile test. In the young pigs, avulsion fracture occurred most commonly in both tests. In the adult pigs, however, mid-substance disruption occurred with quasi-static tensile test and bony avulsion occurred with impact loading test. Patterns of disruption in pig models varies with the relative maturity of the animals tested and mode of force application. A possible explanation for this is the relative strength of the bone and ligament in animals of varied maturity.

Experimentally produced fractures of articular cartilage and bone. The effects of shear forces on the pig knee

Experimental injuries of cartilage and bone were produced by applying shear force to the articular surfaces of the lateral femoral condyles of six-month-old pigs under various loading conditions. The lesions were divided into two groups, 'open' or 'closed', depending on the presence of a crack on the articular surface. Each was further divided into four types according to the depth of penetrating injury: (1) splitting of uncalcified cartilage; (2) splitting at the subchondral plate; (3) subchondral fracture; and (4) intra-articular fracture. When shear force was applied at high speed but with low energy, the articular cartilage surface was the first to crack. At low speed and low energy, splits occurred in the deeper layers first. As the energy increased, both loading conditions eventually resulted in similar open lesions. Experimentally produced shear injuries are useful models for clinical osteochondral fracture, osteochondritis dissecans, and chondromalacia patellae.

[Study on reconstruction of the anterior cruciate ligament in the monkey knee using polyester artificial ligament]

We performed an experimental study of ACL reconstruction utilizing polyester artificial ligament(Leeds-Keio). The quality of regenerated ligaments was compared between two different procedures; in the one 1 cm wide Leeds-Keio ligament was used alone for reconstruction(Group 1) and in the other, Leeds-Keio ligament of the same size was augmented with one-third width of free patellar tendon (Group 2). Eighteen knees of nine Japanese monkeys were used. The specimens were obtained at 2, 6 and 12 months after the operation and investigated macroscopically, microscopically and biomechanically. Regenerated ligaments in Groups 1 and 2 appeared identical and grossly normal. However, more mature and stable ligament was noted in the cylinder of artificial ligaments after 2 months after operation in Group 2 than in Group 1 in terms of both quality and quantity. Biomechanically, however, the maximum the tension in the regenerated ligaments was approximately 1/2-1/3 of that of normal ACL. The authors believe that more mature ligament was made in ACL reconstruction when the artificial ligament was augmented with autogenous soft tissue.

Autogenous meniscus grafts in articular cartilage defects--an experimental study

Many methods have been attempted to repair defects in the articular cartilage involving the subchondral bone, but no satisfactory method has yet been established. We performed an experimental study utilizing autogenous meniscus grafts for defects in the articular cartilage involving the subchondral bone. Sixty-two knees of 31 rabbits were thus treated. Gross and histological examinations were performed in animals sequentially sacrificed after 2 to 24 weeks. In gross examinations, the articular surface was smooth and the degenerative changes were slight although the grafted area appeared as a piece of whitish meniscus in all experimental knees. Histologically, 12 weeks were necessary for complete union in the superficial zone of the junction between the grafted meniscus and the subchondral bone. However, the junction in the deep zone was completely united after two weeks. Degenerative changes, such as fibrillation or ulceration were not noted on the surface of the grafted meniscus. The chondrocytes of the meniscus survived for as long as 24 weeks. The autogenous meniscus graft appears to be a promising alternative for defects in the articular cartilage.

Cartilage lesions in the knee of adolescents and young adults: arthroscopic analysis

In this article, the mechanism of occurrence and development of cartilage lesions as well as the relationship between pain and conditions of cartilage lesions will be discussed. The study was based on the findings from arthroscopic analyses, plain radiographs, and arthrograms. Sixty-five joints of 63 patients with cartilage lesions were examined. We have made the following conclusions. Cartilage lesions do not start necessarily from the surface layers of the cartilage. Lesions may originate in the subchondral bone and develop toward the surface, causing severe pain. Cartilage lesions, resulting in little pain, are related closely to joint instability, indicating that the lesion occurrence is affected by unnatural shearing stress rather than by direct force applied to the joint surface. Thus, prevention and treatment should focus on removing the shearing stress. The purpose of this article is to examine how cartilage lesions relate to patient symptoms. Additionally, untreated lesions possibly could develop into the early stage of osteoarthrosis of the knee, causing exposure of the subchondral bone and thus continuous pain.

A stress analysis of the proximal tibia after insertion of the endoprosthesis

Detailed investigation for the local stress increment at the fixation post bottom of an artificial knee joint was performed by two-dimensional finite element method. A strain measurement was also conducted by wire strain gauges on a cancellous bone with a special method. It was made clear that a curvature with a certain extent of radius was necessary for the corner of a fixation post and application of acrylic cement with a certain extent of thickness (3 mm less than or equal to) was effective for stress relaxation, and that an optimum value (10(-1)-10 GPa) existed for elastic modulus of bone cement.

Clinical and roentgenological studies on malalignment disorders of the patello-femoral joint. Part III: Lesions of the patellar cartilage and subchondral bone associated with patello-femoral malalignment

This study was aimed at clarifying what mechanism of patello-femoral malalignment causes cartilage lesions and how the lesions are related to the symptoms. The study was composed of a laboratory experiment and clinical observations on 127 joints of 123 patients. In the clinical observations, cartilage lesions on the patella as well as on the groove and condyles of the femur were studied by performing either arthroscopy or open surgery. Changes of the subchondral bone of the patella were also examined through sky-line view roentgenograms to determine their relationship with cartilage lesions. From these observations, it was concluded that cartilage lesions are caused by shearing stresses produced by the abnormal motion of the patella due to malalignment, often accompanied by open or closed (to the joint cavity) subchondral lesions. The experiment showed that various types of cartilage-bone damage could be brought about depending on various combined factors of velocity and energy of the stressing force. Based on our theory, a reasonable treatment is presented.

Clinical and roentgenological studies on malalignment disorders of the patello-femoral joint. Part II: Relationship between predisposing factors and malalignment of the patello-femoral joint

To clarify the relationship between the predisposing factors and malalignment of the patello-femoral joint, a study was conducted on the basis of roentgenograms of 621 cases in which a disorder of the dérangement was suspected in at least one knee. The degree of alignment was classified into four grade groups according to the dynamic skyline view arthrograms. Each predisposing factor was expressed by patellar tendon-patella ratio, patellar facet ratio, depth index, and femoro-tibial axis angle. As to each of the parameters each joint was categorized into three classes, on the basis of its mean and standard deviation. The frequency of occurrence of each of the three classes in each of the grade groups was then examined. For the patellar shape, the joints were categorized according to Baumgartl's taxonomy. The study indicates that there exists a causal relationship between the predisposing factors such as patella alta, narrow medial facet, shallow patellar groove of femur and unstable patellar shape, and the patello-femoral malalignment.

Clinical and roentgenological studies on malalignment disorders of the patello-femoral joint. Part I: Classification of patello-femoral alignments using dynamic sky-line view arthrography with special consideration of the mechanism of the malalignment disorders

Dynamic sky-line view arthrography at 30, 60, and 90 flexion degrees was carried out on 1,242 knees of 621 cases who claimed trouble with at least one knee. The patient's age range was from 15 to 35 years. Alignment of the patello-femoral joint was classified into four groups; Grade I: The patello-femoral joint is congruent in all the three views. Grade II: The view taken at 30 degrees shows the joint space open in the medial facet but closed in the view at 60 degrees. Grade III: The medial interspace is open at 60 degrees but closed at 90 degrees. Grade IV: The medial joint space is open in all three views. Grade distribution of all cases studied was: Grade I, 62.1%; Grade II, 25.8%; Grade III, 6.7%; and Grade IV, 5.4%. Clinical disorders thus occur at high percentages in the groups of Grades III and IV. Based on this observation, the mechanism of the malalignment disorders of the patello-femoral joint is discussed.

A new method of closed reduction using the spring action of Kirschner wires for fractures of the tibial plateau--a preliminary report

The treatment of fractures of the lateral tibial plateau is still a subject of controversy. Many authors have emphasized the importance of early mobilization of the knee joint following fractures of the tibial plateau. However, local depression fractures of the tibial plateau occur quite frequently in elderly patients and have presented many difficult problems in management. In 1982, the authors developed a new method of closed reduction using the spring action of Kirschner wires for severely displaced local depression fractures of the tibial plateau. The principle of this procedure is to apply continuous positive pressure to the depressed fragment for its reduction and retention. By re-establishing stability in the fracture, active knee mobilization can be allowed from the beginning. Seven patients were treated with this procedure, and the results of short-term follow-up, ranging from three to 26 months, were promising as to the range of motion, stability and relief of pain.