Aims

This study used an artificial neural network (ANN) model to determine the most important pre- and perioperative variables to predict same-day discharge in patients undergoing total knee arthroplasty (TKA).

Aims

Ideal component sizing may be difficult to achieve in unicompartmental knee arthroplasty (UKA). Anatomical variants, incremental implant size, and a reduced surgical exposure may lead to over- or under-sizing of the components. The purpose of this study was to compare the accuracy of UKA sizing with robotic-assisted techniques versus a conventional surgical technique.

1. Chondromalacia, sometimes a precursor of osteoarthritis, is present in the articular cartilage of the patella of most people by the age of thirty; it causes symptoms in only a few, and it gives rise to osteoarthritis in fewer still. It may progress slowly or quickly but there is no clinical method of assessing the prognosis at an early stage. 2. The earliest change is swelling of the cartilage associated with a decrease in the chondroitin sulphuric acid content of the matrix. Later the cartilage fissures and flakes off to expose the bone, and there are reactive changes in the cartilage, bone and synovial membrane. The process is described and the etiology discussed. 3. The symptoms, signs and treatment are discussed. Operation, which has been performed only when there are disabling symptoms, may consist in removing part or the whole of the articular cartilage, or in excision of the patella. The results in forty-six knees are given

We studied the early cartilage changes in osteoarthritis, examining the most normal appearing articular cartilage from the hips of 17 patients. Normal appearing cartilage from five patients treated for fractures was used as control material. Two different types of clone were found. The first had increased staining for proteoglycan and was thought to have been engaged in the synthesis of matrix. The other type was associated with a severe deficiency of proteoglycan, matrix streaks and evidence of degradation and phagocytosis of matrix components. Immunohistochemistry demonstrated large amounts of chondroitin 4 and 6 sulphate about the synthetic-type clones, and little or no reactivity about the degenerative clones which lay more superficially and were associated with matrix destruction. Clones appeared to be engaged in either matrix synthesis or its destruction. The disease process of osteoarthritis appeared to begin at the surface of the articular cartilage

on in vitro incubation of articular and epiphysial cartilage of the ulna of the domestic pig 70 to 80 per cent of [U-. 14. C] glucose was metabolised to . 14. C-lactate, but cartilage of the epiphysial plate produced up to five times as much . 14. C-CO. 2. as articular cartilage, and the specific radioactivity of . 14. C (or . 35. S)-chondroitin 4 (6)-sulphate isolated from epiphysial cartilage (following . 35. S-sulphate incorporation) was about twice as high as that of articular cartilage. Six weeks after an osteotomy on both sides of the proximal epiphysial plate of the left ulna, the glucose uptake, lactate production, and the specific radioactivity of the glycosaminoglycans displayed no significant differences when compared with those of the corresponding epiphysial plate of the control right ulna, whereas a 50 per cent increase in the oxidation of . 14. C-glucose to . 14. c-co. 2. was observed

Aims

Poly (ADP-ribose) polymerase (PARP) inhibitor has been reported to attenuate inflammatory response in rat models of inflammation. This study was designed to investigate the effect of PARP signalling in osteoarthritis (OA) cartilage inflammatory response in an OA rat model.

Primary osteoarthritis of the ankle with no history of trauma is rare. We report the use of a low tibial osteotomy on 18 ankles in 18 patients, two men and 16 women. The osteotomy is designed to correct the varus tilt and anterior opening of the distal tibial joint surface where it has been shown by weight-bearing radiographs and arthroscopy that there is healthy articular cartilage on the lateral side of the ankle. An opening-wedge osteotomy was used to achieve slight overcorrection. Follow-up of the 18 ankles at an average of 6 years 11 months (2.7 to 12.10) showed the results by our own scoring system to be excellent in six ankles, good in nine, and fair in three with no poor results. Of the three patients with fair results, two had been undercorrected and the third had little residual articular cartilage. Arthroscopic examination of ten ankles showed repair by fibrocartilage in seven. We conclude that slight overcorrection of deformity by low tibial osteotomy is effective in treating intermediate-stage primary osteoarthritis of the ankle

Aims

To explore the clinical relevance of joint space width (JSW) narrowing on standardized-flexion (SF) radiographs in the assessment of cartilage degeneration in specific subregions seen on MRI sequences in knee osteoarthritis (OA) with neutral, valgus, and varus alignments, and potential planning of partial knee arthroplasty.

Biochemical changes in the articular cartilage of the knees of mature dogs, one with natural and four with surgically induced osteoarthritis, have been investigated. The four dogs were killed three, six, nine and forty-eight weeks after division of the right anterior cruciate ligament, the left knees serving as controls. The cartilage of the joints operated on was thicker and more hydrated than the control cartilage; the proteoglycans were more easily extracted and had higher galactosamine/glucosamine molar ratios. The proportion of proteoglycans firmly associated with collagen, and hence not extractable, diminished before fibrillation was demonstrable by indian ink staining of the surface. These biochemical changes were present throughout the entire cartilage of the joints operated on of the dogs killed more than three weeks later, and of the dog with natural osteoarthritis. The results suggest that in response to altered mechanical stresses the chondrocytes synthesise proteoglycans that contain more chondroitin sulphate relative to keratin sulphate than normally, as in immature articular cartilage

After a severe ankle sprain the incidence of residual complaints, particularly on the medial side of the joint, is high. We studied a consecutive series of 30 patients who had operative repair of acute ruptures of lateral ligaments. During operation, arthroscopy revealed a fresh injury to the articular cartilage in 20 ankles, in 19 at the tip and/or anterior distal part of the medial malleolus as well as on the opposite medial facet of the talus. In six patients, a loose piece of articular cartilage was found. We conclude that in patients with a rupture of one or more of the lateral ankle ligaments after an inversion injury, an impingement occurs between the medial malleolus and the medial facet of the talus. Patients with a lesion of the lateral ankle ligament caused by a high-velocity injury (a faulty landing during jumping or running) had a higher incidence of macroscopic cartilage damage (p < 0.01), medially-located pressure pain (p = 0.06) and medially-located complaints at one-year follow-up (p = 0.02) than those with a low-velocity injury (a stumble)

Damage to articular cartilage is a common injury, for which there is no effective treatment. Our aims were to investigate the temporal sequence of the repair of articular cartilage and to define a critical-size defect. Full-thickness defects were made in adult male New Zealand white rabbits. The diameter (1 to 4 mm) of the defects was varied in order to determine the effect that the size and depth of the defect had on its healing. The defects were made in the femoral groove of the knee with one defect per knee and eight knees per group. The tissues were fixed in formalin at days 3, 7, 14, 21, 28, 42, 84 and 126 after operation and the sections stained with Toluidine Blue. These were then examined and evaluated for several parameters including the degree of metachromasia and the amount of subchondral bone which had reformed in the defect. The defects had a characteristic pattern of healing which differed at different days and for different sizes of defect. Specifically, the defects of 1 mm first peaked in terms of metachromasia at day 21, those of 2 mm at day 28, followed by defects of 3 mm and 4 mm. The healing of the subchondral bone was slowest in defects of 1 mm

Aims

The objective of this study is to assess the use of ultrasound (US) as a radiation-free imaging modality to reconstruct 3D anatomy of the knee for use in preoperative templating in knee arthroplasty.

Autologous chondrocyte implantation (ACI) and mosaicplasty are both claimed to be successful for the repair of defects of the articular cartilage of the knee but there has been no comparative study of the two methods. A total of 100 patients with a mean age of 31.3 years (16 to 49) and with a symptomatic lesion of the articular cartilage in the knee which was suitable for cartilage repair was randomised to undergo either ACI or mosaicplasty; 58 patients had ACI and 42 mosaicplasty. Most lesions were post-traumatic and the mean size of the defect was 4.66 cm. 2. The mean duration of symptoms was 7.2 years and the mean number of previous operations, excluding arthroscopy, was 1.5. The mean follow-up was 19 months (12 to 26). Functional assessment using the modified Cincinatti and Stanmore scores and objective clinical assessment showed that 88% had excellent or good results after ACI compared with 69% after mosaicplasty. Arthroscopy at one year demonstrated excellent or good repairs in 82% after ACI and in 34% after mosaicplasty. All five patellar mosaicplasties failed. Our prospective, randomised, clinical trial has shown significant superiority of ACI over mosaicplasty for the repair of articular defects in the knee. The results for ACI are comparable with those in other studies, but those for mosaicplasty suggest that its continued use is of dubious value

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The present study investigates the effectiveness of platelet-rich plasma (PRP) gel without adjunct to induce cartilage regeneration in large osteochondral defects in a rabbit model.

Aims

Parathyroid hormone (PTH) (1-34) exhibits potential in preventing degeneration in both cartilage and subchondral bone in osteoarthritis (OA) development. We assessed the effects of PTH (1-34) at different concentrations on bone and cartilage metabolism in a collagenase-induced mouse model of OA and examined whether PTH (1-34) affects the JAK2/STAT3 signalling pathway in this process.

Aims

Osteoarthritis (OA) is a disabling joint disorder and mechanical loading is an important pathogenesis. This study aims to investigate the benefits of less mechanical loading created by intermittent tail suspension for knee OA.

1. The methods by which epiphyses receive their blood supply was studied by means of India ink injections in monkeys. Two types were identified depending upon whether the epiphysis was entirely or partly covered by articular cartilage. In the former, nutrient vessels enter the epiphysis by traversing the perichondrium at the periphery of the plate. In the latter they enter the epiphysis by penetrating the cortex at the side of the epiphysis at a point remote from the epiphysial plate. 2. The histological changes after separation of the second type of epiphysis were also studied. After temporary interference with endochondral ossification marked by increased thickness of the epiphysial plate, healing occurred so rapidly that within three weeks it was difficult to determine that the epiphysis had been separated at all. 3. It is concluded that when nutrient vessels enter an epiphysis at a point remote from the epiphysial plate, that epiphysis can be separated without serious disturbance to its blood supply and accordingly without interference with its capacity for growth. As it has been established that an epiphysis which is entirely covered by articular cartilage cannot be separated without destruction of its blood supply and subsequent avascular necrosis (Harris and Hobson 1956), it is concluded that the prognosis of an epiphysial separation is dependent upon the degree of damage to its blood supply rather than the mechanical disturbance of the epiphysial plate

Aims

Vertebrates have adapted to life on Earth and its constant gravitational field, which exerts load on the body and influences the structure and function of tissues. While the effects of microgravity on muscle and bone homeostasis are well described, with sarcopenia and osteoporosis observed in astronauts returning from space, the effects of shorter exposures to increased gravitational fields are less well characterized. We aimed to test how hypergravity affects early cartilage and skeletal development in a zebrafish model.

Aims

The purpose was to evaluate early clinical, patient-reported, and radiological outcomes of the scapholunate ligament 360° tenodesis (SL 360) technique for treatment of scapholunate (SL) instability.