1. Degenerative arthritis has been produced consistently in adult rabbits by the injection of the proteolytic plant enzyme papain into the hip joint. Arthritic changes were recognisable radiographically after six weeks. 2. A progression of changes occurred, from loss of acid mucopolysaccharide staining in the matrix, fibrillation, fissuring and erosion of articular cartilage with death of chondrocytes in the weight-bearing areas, to secondary bony changes of subchondral sclerosis, occasional cysts and osteophyte formation. 3. Synovial inflammation occurred with accumulation of cartilage and bone debris in the inferior capsule and later capsular thickening. 4. It is suggested that this arthritis is sufficiently similar to human osteoarthritis to be useful as a model for further studies of the pathogenesis of the disease and the effects of different methods of treatment

Aims

Total knee arthroplasty (TKA) using functional alignment aims to implant the components with minimal compromise of the soft-tissue envelope by restoring the plane and obliquity of the non-arthritic joint. The objective of this study was to determine the effect of TKA with functional alignment on mediolateral soft-tissue balance as assessed using intraoperative sensor-guided technology.

Our study establishes a rabbit model of disc degeneration which requires neither a chemical nor physical injury to the disc. Disc degeneration similar to that seen in man was created at levels proximal (L4-L5) and caudal (L7-S1) to a simulated lumbar fusion and was studied for up to nine months after arthrodesis. Loss of the normal parallel arrangement of collagen bundles within the annular lamellae was observed in intervertebral discs adjacent to the fusion at three months. By six months there was further disorganisation as well as loss of distinction between the lamellae themselves. By nine months the structure of the disc had been replaced by disorganised fibrous tissue, and annular tears were seen. There was an initial cellular proliferative response followed by loss of chondrocytes and notochordal cells in the nucleus pulposus. Degeneration was accompanied by a decrease in the monomer size of proteoglycans. Narrowing of the disc space, endplate sclerosis and the formation of osteophytes at adjacent disc spaces were observed radiologically

We operated on 16 patients for ulnar neuropathy associated with osteoarthritis of the elbow. They were all male manual workers, with an average age of 51 years at the time of surgery. The severity of the symptoms was McGowan grade 1 in five patients, grade 2 in nine and grade 3 in two. The mean follow-up was 36 months. The operation consists of resecting the osteophytes around the postcondylar groove. The shallow and narrow cubital tunnel is made deep and wide and the ulnar nerve is replaced with its surrounding soft tissues in the enlarged groove. All patients were relieved of discomfort and all showed some improvement or full recovery of motor and sensory function. The ulnar nerve showed no evidence of irritation or adhesion. This procedure also allows early movement of the elbow after operation, because the subcutaneous tissues and muscles have not been detached

A new technique for the transthoracic removal of a prolapsed intervertebral disc in the mid or lower thoracic spine is described. Investigations before operation include thoracic myelography, selective spinal angiography and CT scanning. Image intensification is used at operation to check the level of the prolapse. A tunnel in the coronal plane (vertebrotomy) is made through the posterolateral part of the disc and the adjacent vertebral bodies, to reach the spinal canal at the site of the prolapse. This gives good exposure and enables gentle removal of the disc prolapse and any associated osteophytes, under direct vision without need for retraction or pressure on the dura or spinal cord. Spinal stability is not compromised, and the blood supply of the cord is not disturbed. Five consecutive patients are reported, including one in whom the disc prolapse was calcified and had herniated into the spinal cord. All were treated successfully

Aims

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.

We assessed the long-term outcome of open debridement for the treatment of anterior impingement of the ankle in 27 patients. By using preoperative radiographs to group patients according to both the McDermott and the van Dijk scoring system, we assessed the accuracy of these classifications in predicting outcome. The Ogilvie-Harris scoring system, a visual analogue scale of patient satisfaction, the time to return to full activities, and the ability to return to sports determined the clinical outcome. Follow-up radiographs were used to assess the recurrence of osteophytes. We also assessed the incidence of talar osteochondral lesions at surgery. At a mean follow-up of 7.3 years, 23 of 25 patients (92%) without joint-space narrowing had a good or excellent result. Improvement in the Ogilvie-Harris score was seen in all patients. In athletes, 19 of 24 (79%) were able to return to sports at the same level. Two patients with preoperative joint-space narrowing had a poor result. Osteophytes usually recurred and most patients did not feel that the range of dorsiflexion returned to normal, but symptomatic relief allowed most to return to high-level sport. Our results for non-arthritic joints suggest that this is a safe and successful procedure

1. The antero-posterior or sagittal diameter of the cervical spine has been measured radiographically in fifty-one Japanese men who fell into three groups-twenty with normal cervical spines, eleven with spondylosis but no neurological symptoms, and twenty with spondylosis and myelopathy. 2. The average normal diameter was found smaller by 2·25 millimetres in Japanese men than in European adults examined by other authors. 3. The average initial diameter in cases of spondylosis without neurological symptoms was found to be greater than normal, which suggests that the increased space round the cord helps to avoid compression. 4. The average initial diameter in cases of spondylosis with myelopathy was found to be less than normal, which suggests that compression may be determined by moderate osteophyte formation or disc protrusion. 5. The risk of myelopathy would appear to be high when the average diameter is 12 millimetres or less. 6. The difficulty with such radiological measurements is that standard lateral films cannot always record the degree of encroachment by disc protrusion or by hypertrophy of the soft tissues

1. The capsular changes in osteoarthritis of the hip and their pathogenesis are described, and it is concluded that symptoms are due mainly to this abnormality. 2. The clinical significance and pathogenesis of subchondral sclerosis, cysts, osteophytes, secondary subluxation and new bone formation on the lower border of the femoral neck are discussed. 3. These bony features which can be seen in the radiograph may, under certain circumstances, be correlated with the symptoms. 4. The influence of joint debris and capsular fibrosis upon the symptoms arising in other osteoarthritic joints is considered. 5. The mechanism by which osteoarthritis develops in hip joints with an anatomical abnormality is discussed in relation to the normal functional anatomy of the hip. 6. The evolution of osteoarthritis in dysplasia of the hip is considered with special reference to its diagnosis, prognosis and early treatment. 7. The supposition that osteoarthritis is commonly due to progressive ischaemia in the femoral head has been investigated and is rejected. 8. The cause of idiopathic osteoarthritis remains obscure but the evidence suggests that constitutional rather than local conditions in the joint account for many of these cases

We carried out radial MRI in 30 hips with moderate osteoarthritis and in ten normal hips. On a scout view containing the entire acetabular rim, 12 vertical radial slices were set at 15° intervals. Different appearances were observed in different parts of the joint. In the weight-bearing portion, from 45° anterosuperior to 45° posterosuperior, ‘attenuation’ (n = 16) and ‘disappearance’ (n = 25) were observed as abnormalities of the labrum with ‘capsular stripping’ (n = 29) and ‘extraosseous high signal lesion’ (n = 27) as capsular abnormalities, seen more often in the anterosuperior portion. In all 12 planes there were osteophytes on the acetabular edge (n = 24), femoral head (n = 22) and/or at the central acetabulum (n = 6), a bone cyst on the acetabulum (n = 18) and/or the femoral head (n = 9), irregularity of the articular cartilage (n = 30), and an effusion (n = 28). Our findings indicate that radial MRI may be a useful non-invasive diagnostic method for demonstrating pathology in moderate osteoarthritis of the hip

We have studied the three-dimensional geometry of the proximal humerus on human cadaver specimens using a digitised measuring device linked to a computer. Our findings demonstrated the variable shape of the proximal humerus as well as its variable dimensions. The articular surface, which is part of a sphere varies individually in its orientation as regards inclination and retroversion, and it has variable medial and posterior offsets. These variations cannot be accommodated by the designs of most contemporary humeral components. Although good clinical results can be achieved with current modular and non-modular components their relatively fixed geometry prevents truly anatomical restoration in many cases. To try to restore the original three-dimensional geometry of the proximal humerus, we have developed a new type of humeral component which is modular and adaptable to the individual anatomy. Such adaptability allows correct positioning of the prosthetic head in relation to an individual anatomical neck, after removal of the marginal osteophytes. The design of this third-generation prosthesis respects the four geometrical variations which have been demonstrated in the present study. These are inclination, retroversion, medial offset and posterior offset

We studied 40 patients in whom the patella was not severely deformed and who were undergoing primary total knee arthroplasty (TKA) for osteoarthritis by one surgeon using one type of prosthesis. They were randomly allocated either to have the patella retained or resurfaced with a cemented, all-polyethylene component regardless of the state of the patellar articular cartilage. Apart from removal of osteophytes, no surgery was undertaken on the retained patellae. All 38 surviving patients were evaluated at three years using the HSS knee score and a new, specifically designed Patellar score (maximum score of 30). No TKA was revised, but two patients in the resurfacing group had a further unrelated procedure. The mean HSS and Patellar scores at follow-up were 89 and 28 in the patellar retention group and 83 and 26 in the patellar resurfacing group. Statistically significant lower scores for both were recorded in women and in heavier patients. Stair-climbing ability was significantly better in the retention group. Although there were no complications related to patellar resurfacing, in the medium term we did not find any significant benefit from resurfacing the patella during TKA for osteoarthritis if it was not severely deformed

Aims

The aim of this study was to systematically review the literature for evidence of the effect of a high-fat diet (HFD) on the onset or progression of osteoarthritis (OA) in mice.

Aims

The aim of this study was to report the medium-term outcomes of impaction bone allograft and fibular grafting for osteonecrosis of the femoral head (ONFH) and to define the optimal indications.

Aims

To study the associations of lumbar developmental spinal stenosis (DSS) with low back pain (LBP), radicular leg pain, and disability.

Dynamic muscle-tendon substitution for acute anterior cruciate deficiency in the dog was studied using the semimembranosus muscle-tendon. Nineteen mongrel dogs each had a semimembranosus transfer in one knee; as a control, the anterior cruciate ligament and the semimembranosus were released in the opposite knee. No postoperative immobilisation was used. The anterior drawer sign was assessed before and after operation and when the dogs were killed five months later. Dogs were excluded from the study if they developed infections or contractures of the hind legs. At five months, 11 dogs were available for study. The operated knees were examined histologically and evaluated using a reproducible index of arthritis based on: the macroscopic discoloration of the articular cartilage, the cellularity of the cartilage, the microscopic appearance of the articular surface, the loss of proteoglycans, the formation of osteophytes and the degree of subchondral osteosclerosis. There was no significant difference in the anterior drawer sign or the degree of arthritic changes between knees with a semimembranous transfer and the controls. Examination showed that a muscle-tendon transfer into the tibia was equivalent to transferring the muscle into the posterior capsule--the intra-articular tendon being weak but histologically viable. The transfer did not prevent the anterior drawer sign becoming positive nor the development of osteoarthritis. A second control group, in which three dogs had an arthrotomy and semimembranosus release in both their hind legs, showed that a semimembranosus release alone did not cause osteoarthritis

Aims

The primary aim of this study was to compare the postoperative systemic inflammatory response in conventional jig-based total knee arthroplasty (conventional TKA) versus robotic-arm assisted total knee arthroplasty (robotic TKA). Secondary aims were to compare the macroscopic soft tissue injury, femoral and tibial bone trauma, localized thermal response, and the accuracy of component positioning between the two treatment groups.

Aims

This study aims to determine the proportion of patients with end-stage knee osteoarthritis (OA) possibly suitable for partial (PKA) or combined partial knee arthroplasty (CPKA) according to patterns of full-thickness cartilage loss and anterior cruciate ligament (ACL) status.