The clinical manifestations and pathomechanics of contracture of the extensor mechanism of the knee.
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Experience with thirty-eight Asian children and adolescents who presented with either stiffness of the knee, genu recurvatum, habitual dislocation of the patella or congenital lateral dislocation of the patella showed that all those disorders were manifestations of contracture of the extensor mechanism, which fell into two groups according to the components involved. In Group I the main components affected were in the midline of the limb, namely rectus femoris and vastus intermedius; these patients presented with varying degrees of stiffness of the knee, or worse, with genu recurvatum. In Group II the main components involved were lateral to the midline of the limb, namely vastus lateralis and the ilio-tibial band; these patients presented with habitual dislocation of the patella, or worse, congenital lateral dislocation of the patella. In both groups untreated patients developed secondary adaptive changes such as subluxation of the tibia or marked genu valgum which made operative procedures more formidable and less effective. Release of the contracture should therefore be performed as early as possible. (+info)
Ganglion cysts of the cruciate ligaments detected by MRI.
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Eight patients with ganglion cysts arising from the cruciate ligaments of the knee joint underwent arthroscopic excision after the MR examination. The MR findings, clinical features and arthroscopic findings were evaluated comparatively. (+info)
Spontaneous or traumatic premature closure of the tibial tubercle.
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A premature closure of the physis of the tibial tubercle in a young man has given rise to a shortening of the tibia, a patella alta and a reversed tibial slope of 20 degrees with clinical genu recurvatum. After a proximal open wedge tibial osteotomy all three postural deformities could be restored. The etiology of this complex deformity is discussed. (+info)
Incidence of bradycardia during recovery from spinal anaesthesia: influence of patient position.
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We administered 0.5% plain bupivacaine 4 ml intrathecally (L2-3 or L3-4) in three groups of 20 patients, according to the position in which they were nursed in the post-anaesthesia care unit (PACU): supine horizontal, 30 degrees Trendelenburg or hammock position (trunk and legs 30 degrees elevated). Patients were observed until anaesthesia descended to less than S1. The incidence of severe bradycardia (heart rate < 50 beat min-1) in the PACU was significantly higher in patients in the Trendelenburg position (60%) than in the horizontal (20%, P < 0.01) or hammock (10%, P < 0.005) position. After 90 min, following admission to the PACU, only patients in the hammock position did not have severe bradycardia. In this late phase, the incidence of severe bradycardia in the Trendelenburg group was 35% (P < 0.005) and 10% in patients in the supine horizontal position. In four patients, severe bradycardia first occurred later than 90 min after admission to the PACU. The latest occurrence of severe bradycardia was recorded 320 min after admission to the PACU. We conclude that for recovery from spinal anaesthesia, the Trendelenburg position should not be used and the hammock position is preferred. (+info)
In situ hybridisation and direct fluorescence antibodies for the detection of Chlamydia trachomatis in synovial tissue from patients with reactive arthritis.
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BACKGROUND: Chlamydia trachomatis is associated with Reiter's syndrome and reactive arthritis but the form in which the organism survives in synovial cells is unclear. AIM: To compare in situ hybridisation with direct fluorescence in the detection of inapparent chlamydial infection in synovial tissue. METHODS: Synovial tissue from four patients with reactive arthritis patients was examined using biotin labelled probes for chlamydial DNA and fluorescein isothiocyanate (FITC) labelled monoclonal antibodies against the major outer membrane protein. RESULTS: In two of the four patients, evidence of chlamydial infections was detected by in situ hybridisation in parallel sections but not with FITC labelled monoclonal antibodies. CONCLUSIONS: Detection of chlamydial DNA by in situ DNA hybridisation may be a better way to identify chlamydial infection in synovial tissue than phenotype targeting with FITC conjugated antibodies, which is used as a standard procedure for screening clinical specimens for chlamydia. (+info)
Effects of activation frequency and force on low-frequency fatigue in human skeletal muscle.
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No comparison of the amount of low-frequency fatigue (LFF) produced by different activation frequencies exists, although frequencies ranging from 10 to 100 Hz have been used to induce LFF. The quadriceps femoris of 11 healthy subjects were tested in 5 separate sessions. In each session, the force-generating ability of the muscle was tested before and after fatigue and at 2, approximately 13, and approximately 38 min of recovery. Brief (6-pulse), constant-frequency trains of 9.1, 14.3, 33.3, and 100 Hz and a 6-pulse, variable-frequency train with a mean frequency of 14.3 Hz were delivered at 1 train/s to induce fatigue. Immediately postfatigue, there was a significant effect of fatiguing protocol frequency. Muscles exhibited greater LFF after stimulation with the 9.1-, 14.3-, and variable-frequency trains. These three trains also produced the greatest mean force-time integrals during the fatigue test. At 2, approximately 13, and approximately 38 min of recovery, however, the LFF produced was independent of the fatiguing protocol frequency. The findings are consistent with theories suggesting two independent mechanisms behind LFF and may help identify the optimal activation pattern when functional electrical stimulation is used. (+info)
Common intra-articular T cell expansions in patients with reactive arthritis: identical beta-chain junctional sequences and cytotoxicity toward HLA-B27.
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Spondyloarthropathies constitute a group of autoimmune diseases of special interest because of their tight association with the MHC class I molecule HLA-B27 and the bacterial triggering of some clinical forms called reactive arthritis (ReA). One current hypothesis is the presentation by HLA-B27 of a so-called arthritogenic peptide to T cells. To better focus on the relevant T cell populations within the joint, we performed an extensive beta-chain T cell repertoire analysis of synovial fluid compared with PBL in seven patients, four of whom were characterized as having ReA triggered by Yersinia enterocolitica, Chlamydia trachomatis, or Shigella sonnei. Analysis of the size diversity of the beta-chain complementarity-determining region 3 (CDR3) allowed us to evaluate the degree of T cell clonality in the samples. Oligoclonal T cell expansions were frequently observed in the joint. In one patient, CDR3 amino acid sequences of major expansions using two different BV genes were identical. One dominant T cell expansion and several CDR3 amino acid sequences were identical in two different patients. Furthermore, one sequence was identical with a sequence reported independently in a Salmonella-induced ReA patient. Together, these data indicate a surprisingly high degree of conservation in the T cell responses in recent-onset ReA triggered by different micro-organisms. A CD8+ synovial line expressing shared clonotypes was established and reacted toward several B*2705 lymphoblastoid cell lines, therefore supporting a molecular mimicry phenomenon at the T cell level in the disease mechanism. (+info)
Total knee arthroplasty in bony ankylosis in gross flexion.
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Between June 1993 and December 1994, we performed total knee arthroplasty (TKA) on 27 knees in 24 patients with spontaneous bony ankylosis in severe flexion. The mean age at operation was 43.5 years (30 to 60). No patient had preoperative pain. Three were unable to walk and 21 could manage less than five blocks. The mean duration of the ankylosis was 18.7 years (13 to 25) and its mean position was 105 degree flexion (75 to 135). The preoperative Hospital for Special Surgery Knee Score of 60 points was improved to 87 at the final follow-up three to five years later. All knees were free from pain. The mean range of active flexion in 24 knees was 97 degrees (78 to 115) and the mean arc of movement 91 degrees (78 to 98). The mean fixed flexion deformity was 6 degrees (0 to 25) and the extension lag 8 degrees (0 to 25). Angular deformity was corrected to between 0 degrees and 10 degrees of valgus. Four patients were able to walk one block and 20 five to seven blocks. Thirteen knees (48%) showed some necrosis at the skin edge; one knee required arthrodesis and another resection arthroplasty. One had a recurrence of tuberculous infection requiring arthrodesis. One patient had a rupture of the quadriceps tendon. To date no prosthesis has required revision for loosening. Radiolucency of 1 mm or less about the tibial prosthesis was observed at follow-up in four of the 24 knees. Our results have shown that one-stage TKA and skeletal traction after operation can achieve correction of severe flexion deformity of the knee with marked improvement in the function and quality of life. (+info)