The Knee
The effects of quadriceps muscle loading on three-dimensional patellar movements were studied in vitro with three patterns of muscle loading according to anatomical, mathematical and Q-angle models. Loading of the quadriceps based on the mathematical model resulted in more lateral patellar deviation, 0.5 ± 0.6 cm in 0°, and 0.6 ± 0.9 cm in 15° of knee flexion, than those of the other two models (P...
Not long ago the menisci were regarded as simple spacers in the knee joint, with the only function to make up for the joint surface incongruence between the femur and the tibia. In case of injury to the meniscus, this was removed as thoroughly as possible. Not much was known about the structure of the menisci, their morphology and their function. This has changed fundamentally until the present...
Changes in cartilage thickness, calcified cartilage thickness, subchondral bone plate thickness and cartilage vascularity have been proposed as mediators or initiators of degenerative joint disease, but the changes seen in these parameters in normal ageing have not been determined. Image analysis techniques were used to examine these parameters. Cartilage condition deteriorated significantly with...
A number of different techniques have been employed to assess patellar tracking. Magnetic resonance imaging has the advantage of being safe with no ionising radiation, and also the ability to obtain axial and sagittal images of the knee and patella.The initial MRI technique for the assessment of patellar tracking involved incremental flexion or extension of the knee between 0-30° with the patient...
When patellar, patellofemoral or anterior knee pain is investigated, severe and major pathology of the patellar bone must be considered.InfectionOsteomyelitis occurs rarely by haematogenous spread or infrequently by direct implantion. A Brodie's abscess of the patella with sequestrum was demonstrated.TumourTumours of bone affecting the patella are primary or secondary, benign or malignant. A secondary...
We report the results of 53 knees with lateral compartmental osteoarthritis treated by unicompartmental arthroplasty with the Oxford Meniscal Knee. The mean follow-up was 5 years. Eleven knees required further surgery. Six of the revisions were for early dislocation of the meniscal bearing, three because of late infection, one because of loosening of the tibial component and one because of a stress...
Isolated arthritis of the patello-femoral joint is much more common than is often appreciated, McAlindon, in 1992, reported symptomatic arthritis in 8% of women and 4% of men over the age of 55. Conventional treatment of patellectomy for severe symptoms does not give very good results with only 50% of patients achieving satisfactory pain relief and function (Ackroyd, 1976).Lubinus in 1978 designed...
Many studies have been published on whether the patella should be resurfaced during total knee replacement, but controlled randomised prospective studies have not been reported. Such a study was undertaken at Winford Orthopaedic Hospital, Bristol, between 1991 and 1992. Eighty patients, undergoing kinematic knee replacement, were randomly allocated to receive either patella resurfacing or merely...
In the assessment of meniscal tears the accuracy of MRI should be approximately 95%. There are two potential sources of error in the interpretation of meniscal appearances in the unoperated meniscus. The first relates to the requirement for familiarity with normal structures which may mimic abnormalities. The second relates to the inherent inaccuracies of the technique which although small, result...
IntroductionKnee flexion-extension movements are an integral part of daily activity, not only in occasional large movements such as when sitting or rising from a chair, but also as an integral part of normal locomotion. A stiff-legged gait would cause the centre of gravity to rise and fall with every stride, which would waste energy and thus be very tiring. As the foot is projected forwards to meet...
Worldwide it is estimated that there are over 10 000 000 cases of HIV infection. The CDC estimates that by the year 2000, this number may rise to 40 000 000. They estimate that the number of HIV carriers in the United States is 1 000 000 to 1 5000 000. Because it is against the law to HIV test a patient against his/her will, this figure may be an underestimation. The CDC has said that over 80%...
Dislocation in this age group does not vary greatly from that in the child except that most of the congenital/syndrome problems will have been addressed and as skeletal maturity approaches more satisfactory re-alignment procedures involving tibial tubercle surgery become possible.The standard classification is not a great deal of help in management and a paradox becomes apparent in that the amount...
We report the early results of the treatment of seven patients with osteochondritis dissecans of the femoral condyles with poly-p-dioxanone pin fixation. All patients had large osteochondral lesions with discontinuous articular cartilage but with fragments remaining in situ. These patients were followed-up for between 4 and 48 months, mean follow-up of 31 months. Six patients showed radiographic...
Between 1975 and 1995 we have performed 200 patello femoral arthroplasties. Our last review of results was reported in 1990, about 87 knees operated between 1975 and 1986, using the Richard's femoro patellar resurfacing. At the time of this study five patients had died and 10 lost for follow up.In the 72 remaining cases there were 65 patients (56 women, 9 men) seven patients had a bilateral procedure...
Objective: Intra-articular cysts behind the posterior cruciate ligament are rare and generally described as ganglion cysts. We describe five cases where such cysts were thought to be synovial cysts. Materials and methods: Five patients where MRI showed a cyst behind the posterior cruciate ligament were prospectively identified. All were subsequently rescanned. Results: The cyst was absent in all...
(1) Diagnostic tests for the evaluation of the painful TKR-- history/physical exam-- plain radiographs-- scintigraphy-- technetium/gallium/indium-- aspiration with synovial fluid analysis-- arthrography-- sinograms-- selective local anesthetic injections-- articular-- periarticular-- phentolamine injection-- sympathetic block-- pain unit consultation(2) Causes of a painful TKRA. Intra-articular problems--...
A complication of meniscal bearing total knee replacements is subluxation/dislocation of the rotating platform. In this article we describe two cases of platform dislocation occurring after several years, with no history of trauma.
The management of the patella in TKR has been controversial since Freeman in the UK and Insall in the USA first looked at the question of resurfacing in the late 1970s and there is, as yet, no absolute evidence in favor of resurfacing. The picture has been confused by multiple variables and assessment methods, misleading information and, perhaps to a lesser degree, concerns about the malpractice...