1. A study of normal and osteoarthritic hyaline cartilage has been made with the electron microscope and x-ray diffraction.

2. Normal cartilage consists of a three-dimensional network of collagen fibrils with no preferred orientation, surrounded by a matrix containing polysaccharide.

3. In the osteoarthritic joint the collagen fibrils show definite orientation and a decreased proportion of ground substance. X-ray diffraction confirms this and shows the orientation to be at right angles to the surface of the femoral head.

4. Tensional forces across the joint may explain why osteoarthritic changes first appear in the non-weight-bearing area of the joint.

We describe our technique and rationale using hybrid fixation for primary total hip arthroplasty (THA) at the Hospital for Special Surgery. Modern uncemented acetabular components have few screw holes, or no holes, polished inner surfaces, improved locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented sockets can be combined with highly cross-linked polyethylene liners, which have demonstrated very low wear and osteolysis rates after ten to 15 years of implantation. The results of cement fixation with a smooth or polished surface finished stem have been excellent, virtually eliminating complications seen with cementless fixation like peri-operative femoral fractures and thigh pain. Although mid-term results of modern cementless stems are encouraging, the long-term data do not show reduced revision rates for cementless stems compared with cemented smooth stems. In this paper we review the conduct of a hybrid THA, with emphasis on pre-operative planning, surgical technique, hypotensive epidural anaesthesia, and intra-operative physiology.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):54–9.

Aims. The aim of this study was to estimate time to arthroplasty among patients with hip and knee osteoarthritis (OA), and to identify factors at enrolment to first-line intervention that are prognostic for progression to surgery. Methods. In this longitudinal register-based observational study, we identified 72,069 patients with hip and knee OA in the Better Management of Patients with Osteoarthritis Register (BOA), who were referred for first-line OA intervention, between May 2008 and December 2016. Patients were followed until the first primary arthroplasty surgery before 31 December 2016, stratified into a hip and a knee OA cohort. Data were analyzed with Kaplan-Meier and multivariable-adjusted Cox regression. Results. At five years, Kaplan-Meier estimates showed that 46% (95% confidence interval (CI) 44.6 to 46.9) of those with hip OA, and 20% (95% CI 19.7 to 21.0) of those with knee OA, had progressed to arthroplasty. The strongest prognostic factors were desire for surgery (hazard ratio (HR) hip 3.12 (95% CI 2.95 to 3.31), HR knee 2.72 (95% CI 2.55 to 2.90)), walking difficulties (HR hip 2.20 (95% CI 1.97 to 2.46), HR knee 1.95 (95% CI 1.73 to 2.20)), and frequent pain (HR hip 1.56 (95% CI 1.40 to 1.73), HR knee 1.77 (95% CI 1.58 to 2.00)). In hip OA, the probability of progression to surgery was lower among those with comorbidities (e.g. ≥ four conditions; HR 0.64 (95% CI 0.59 to 0.69)), with no detectable effects in the knee OA cohort. Instead, being overweight or obese increased the probability of OA progress in the knee cohort (HR 1.25 (95% CI 1.15 to 1.37)), but not among those with hip OA. Conclusion. Patients with hip OA progressed faster and to a greater extent to arthroplasty than patients with knee OA. Progression was strongly influenced by patients’ desire for surgery and by factors related to severity of OA symptoms, but factors not directly related to OA symptoms are also of importance. However, a large proportion of patients with OA do not seem to require surgery within five years, especially among those with knee OA. Cite this article: Bone Joint J 2022;104-B(7):792–800

1. The cause of cyst formation lies in the major overloading of certain regions caused by the unevenness of the articular surface produced by the arthritic process.

2. Photoelasticity investigations disclose an overburdening of the bone beneath the surface of the joint, which in turn markedly resembles the shapes of actual cysts.

3. The results of this investigation fit organically into the logical sequence of processes in accordance with our theory.

4. This theory is further borne out by the successful formation of cyst phenomena in healthy joints by overloading (Trias 1961).

5. Our theory has no immediate practical bearing on the treatment of arthritic cysts. However, it uncovers certain interesting aspects of the behaviour of bone tissues under mechanical overloading above the limits of biological, though below those of mechanical bearing capacity. Conclusions arising therefrom might in many respects be useful in research into the physiology of bone.

1. An attempt has been made to correlate the radiographic appearances and the morbid anatomy of the cystic changes that occur in the head of the femur in advanced osteoarthritis.

2. The suggestion is made that these lesions are foci of traumatic bone necrosis. Repair may be complicated by the subsequent entrance of synovial fluid through defects in the surface.

A clinical and radiological study was conducted on 97 total hip replacements performed for congenital hip dislocation in 79 patients between 1989 and 1998 using a three-dimensional custom-made cementless stem. The mean age at operation was 48 years (17 to 72) and the mean follow-up was for 123 months (83 to 182).

According to the Crowe classification, there were 37 class I, 28 class II, 13 class III and 19 class IV hips. The mean leg lengthening was 25 mm (5 to 58), the mean pre-operative femoral anteversion was 38.6° (2° to 86°) and the mean correction in the prosthetic neck was −23.6° (−71° to 13°). The mean Harris hip score improved from 58 (15 to 84) to 93 (40 to 100) points. A revision was required in six hips (6.2%). The overall survival rate was 89.5% (95% confidence interval 89.2 to 89.8) at 13 years when two hips were at risk.

This custom-made cementless femoral component, which can be accommodated in the abnormal proximal femur and will correct the anteversion and frontal offset, provided good results without recourse to proximal femoral corrective osteotomy.

Aims. To report early (two-year) postoperative findings from a randomized controlled trial (RCT) investigating disease-specific quality of life (QOL), clinical, patient-reported, and radiological outcomes in patients undergoing a total shoulder arthroplasty (TSA) with a second-generation uncemented trabecular metal (TM) glenoid versus a cemented polyethylene glenoid (POLY) component. Methods. Five fellowship-trained surgeons from three centres participated. Patients aged between 18 and 79 years with a primary diagnosis of glenohumeral osteoarthritis were screened for eligibility. Patients were randomized intraoperatively to either a TM or POLY glenoid component. Study intervals were: baseline, six weeks, six-, 12-, and 24 months postoperatively. The primary outcome was the Western Ontario Osteoarthritis Shoulder QOL score. Radiological images were reviewed for metal debris. Mixed effects repeated measures analysis of variance for within and between group comparisons were performed. Results. A total of 93 patients were randomized (46 TM; 47 POLY). No significant or clinically important differences were found with patient-reported outcomes at 24-month follow-up. Regarding the glenoid components, there were no complications or revision surgeries in either group. Grade 1 metal debris was observed in three (6.5%) patients with TM glenoids at 24 months but outcomes were not negatively impacted. Conclusion. Early results from this RCT showed no differences in disease-specific QOL, radiographs, complication rates, or shoulder function between uncemented second-generation TM and cemented POLY glenoids at 24 months postoperatively. Revision surgeries and reoperations were reported in both groups, but none attributed to glenoid implant failure. At 24 months postoperatively, Grade 1 metal debris was found in 6.5% of patients with a TM glenoid but did not negatively influence patient-reported outcomes. Longer-term follow-up is needed and is underway. Cite this article: Bone Jt Open 2021;2(9):728–736

We have assessed the results of 34 simple excisions of the trapezium, with no additional soft-tissue procedures, in 30 patients. At a median follow-up of five years (2 to 22), 16 thumbs (47%) were completely painfree and a further 10 (29%) were slightly painful after use. Nineteen thumbs (56%) had no functional disability, but thumb-pinch strength was reduced by about 20%. No patient had painful degeneration at the scaphotrapezial pseudarthrosis.

We measured the effect of arthroscopic lavage and debridement of the osteoarthritic knee by comparing objective measurements of thigh muscle function before and after operation. There was some improvement in quadriceps isokinetic torque at six and 12 weeks after joint lavage but not after debridement. Neither method significantly relieved the patients' symptoms.

Degenerative changes of the first carpometacarpal joint commonly cause pain, weakness and adduction deformity. Many patients respond to conservative treatment, but in resistant cases an abduction wedge osteotomy of the base of the first metacarpal has been found to relieve symptoms with less complications than other operations. Twenty-one patients with 23 osteotomies have been reviewed, with a follow-up from 2 to 17 years. All have had lasting relief from pain and consider that they have full function, with no stiffness or limited abduction. Osteotomy is indicated mainly for cases where the arthritis is confined to the carpometacarpal joint, but also relieves pain in cases of peritrapezial arthritis.