Continuous strontium administration first induces typical "rickets" in young rats receiving adequate calcium phosphorus and vitamin D but later the widened cartilage spontaneously calcifies intermittently leaving transverse bands consisting largely of osteoid tissue in the metaphysis; in addition to intermittent calcification bone changes indicate that skeletal growth is not uniformly progressive. Subsequently areas of the epiphysial cartilage fail to calcify and localised defects develop; among these are wedge-shaped metaphysial osteoid tissue masses, "invagination" of the epiphysial plate to form multiple nodules of cartilage with proliferating cells in the middle and hypertrophic ones at the periphery, perforation and fragmentation of the epiphysial plate with formation of large cartilage nodules. Multiple cartilage nodules of different sizes appear in the epiphysis, metaphysis and bone shaft. Most bone margins are lined by osteoid seams which only slowly calcify and concomitantly resorption is decreased so that the rate of remodelling of the skeleton is diminished. This type of process may help to explain the results of treatment of osteoporosis by strontium administration

In a series of seventeen patients with unilateral osteoarthritis of the hip a scintiscanning follow-up study was made before and after total hip replacement for the assessment of the normal course of the 87mSr-scintiscan. In another series of twenty-eight patients with total hip replacement a photoscan was made as a supplement for the diagnosis of loosening of one or both components of a total hip implant. In most of these cases it proved to be a useful method, especially when clinical and raidological examination was inconclusive. It is concluded that up to six months after operation increased osteoblastic activity exists; the scintiscan became normal after that time. 87mSr scintiscanning offers a safe and simple technique for the assessment of the success and stability of total hip arthroplasty. It is also a useful aid for the early detection of loosening and infection. The procedure can help in the differential diagnosis of complaints after total hip replacement.

We investigated whether strontium-enriched calcium phosphate cement (Sr-CPC)-treated soft-tissue tendon graft results in accelerated healing within the bone tunnel in reconstruction of the anterior cruciate ligament (ACL). A total of 30 single-bundle ACL reconstructions using tendo Achillis allograft were performed in 15 rabbits. The graft on the tested limb was treated with Sr-CPC, whereas that on the contralateral limb was untreated and served as a control. At timepoints three, six, nine, 12 and 24 weeks after surgery, three animals were killed for histological examination. At six weeks, the graft–bone interface in the control group was filled in with fibrovascular tissue. However, the gap in the Sr-CPC group had already been completely filled in with new bone, and there was evidence of the early formation of Sharpey fibres. At 24 weeks, remodelling into a normal ACL–bone-like insertion was found in the Sr-CPC group. Coating of Sr-CPC on soft tissue tendon allograft leads to accelerated graft healing within the bone tunnel in a rabbit model of ACL reconstruction using Achilles tendon allograft.

Cite this article: Bone Joint J 2013;95-B:923–8.

1. The detailed anatomy and calcification of the upper half of the tibia in rabbits varying in age from six weeks to twelve months has been studied. 2. The structure of the bone varies at different levels, but a section taken from the same level in the tibia from animals of the same age presents a reasonably constant picture. 3. It has been shown that this variation in structure at different levels is directly related to a difference between the axis of growth and the bone axis. This difference is a result of the unique shape of the tibia. 4. Autoradiographic studies confirm the localised concentration of radioactive strontium in areas of active bone formation where uptake is rapid. 5. The long retention of radioactive strontium in the skeleton (that is, the slow turnover) is a result of the slowness of resorption of bone (endosteal, periosteal or Haversian) in the cortex. Not only is the process slow but it is extremely localised. 6. The significance of these anatomical and physiological characteristics in relation to radiation injury is discussed

1. Stable strontium in large amount in the diet of rats initially inhibits calcification and induces rickets. 2. Changes later become atypical and a complex series of epiphysial plate defects develops: formation of localised osteoid wedges in the metaphysis; invagination of the epiphysial plate and sequestration of multiple cartilage nodules into the marrow cavity; and, in severely affected animals, localised loss of part or parts of the epiphysial plate with formation of large cartilage nodules in the metaphysis and epiphysis. 3. The appearance of cartilage nodules in the metaphysis in man has been shown to be associated with changes in the epiphysial plate, but much of the information is radiological and therefore incomplete, and detailed cellular changes are seldom available. 4. Some of the conditions mentioned, which have presented difficulty in interpretation, partly because of their rarity but also because of lack of knowledge of the fundamental processes concerned, are multiple exostoses and endochondromatoses, metaphysial dysostosis and osteochondritis. 5. Comparison of basic mechanisms revealed in this study with those supposed to occur in human cartilage dystrophies demonstrates that strontium rickets mimics some changes occurring in chronic renal rickets; that invagination of the epiphysial plate and cartilage nodule sequestration could account for the development of multiple exostoses and some endochondromatoses; and that localised endochondral defects in calcification can induce epiphysial changes resembling osteochondritis juvenilis, demonstrating that avascular necrosis is not necessarily the mechanism initiating epiphysial deformity

1. Hitherto, no study has been reported on the relative quantitative contributions of blood supply by the different arterial systems of long bone. This paper is a report on such a study in the young adult rabbit. 2. The rates and regional distributions of the blood supply of the nutrient as well as other arteries of the femur were studied after ligation of the nutrient artery. The average rates of reduction in blood flow per minute for the first five minutes through the entire femur as well as the shaft, and the epiphysis and metaphysis on each end, were measured and analysed. The bone blood flow was measured by the method of bone clearance of blood strontium 85. 3. The normal average rate of blood flow through the femurs of average weight of 9·38 grammes was 0·90±0·05 millilitres per minute, or 9·60±0·47 millilitres per minute per 100 grammes of bone. 4. The nutrient artery contributed at least 46 per cent of the normal total blood supply of the entire femur and at least 71 per cent of the normal total blood flow of the shaft including its marrow, and 37 per cent and 33 per cent of the normal total blood flow of the upper and the lower epiphysial and metaphysial areas respectively. 5. About 63 per cent, 30 per cent and 67 per cent of the total normal blood flow through the upper epiphysis and metaphysis, the shaft and the lower epiphysis and metaphysis respectively are still intact in the first five minutes after ligation of the nutrient artery, which represent the approximate proportions of the blood supply by the other regional arteries. 6. These quantitative data obtained in this study offer good support to the qualitative observations made by many previous workers

Aims

Bone health assessment and the prescription of medication for secondary fracture prevention have become an integral part of the acute management of patients with hip fracture. However, there is little evidence regarding compliance with prescription guidelines and subsequent adherence to medication in this patient group.

Aims

Ceramic-on-ceramic (CoC) bearings in total hip arthroplasty (THA) are commonly used, but concerns exist regarding ceramic fracture. This study aims to report the risk of revision for fracture of modern CoC bearings and identify factors that might influence this risk, using data from the National Joint Registry (NJR) for England, Wales, Northern Ireland and the Isle of Man.

Aims

The success of anterior cruciate ligament reconstruction (ACLR) depends on osseointegration at the graft-tunnel interface and intra-articular ligamentization. Our aim was to conduct a systematic review of clinical and preclinical studies that evaluated biological augmentation of graft healing in ACLR.

Aims

Treatment guidelines for atypical femoral fractures associated with bisphosphonates have not been established. We conducted a systematic review of the treatment of atypical femoral fractures first, to evaluate the outcomes of surgical fixation of complete atypical fractures and secondly, to assess whether prophylactic surgery is necessary for incomplete atypical fractures.

Aims

We evaluated the short-term functional outcome and prevalence of bearing-specific generation of audible noise in 301 patients (336 hips) operated on with fourth generation (Delta) medium diameter head, ceramic-on-ceramic (CoC) total hip arthroplasties (THAs).

This systematic review of the literature summarises the clinical experience with ceramic-on-ceramic hip bearings over the past 40 years and discusses the concerns that exist in relation to the bearing combination. Loosening, fracture, liner chipping on insertion, liner canting and dissociation, edge-loading and squeaking have all been reported, and the relationship between these issues and implant design and surgical technique is investigated. New design concepts are introduced and analysed with respect to previous clinical experience.

We reviewed the literature on the currently available choices of bearing surface in total hip replacement (THR). We present a detailed description of the properties of articulating surfaces review the understanding of the advantages and disadvantages of existing bearing couples. Recent technological developments in the field of polyethylene and ceramics have altered the risk of fracture and the rate of wear, although the use of metal-on-metal bearings has largely fallen out of favour, owing to concerns about reactions to metal debris. As expected, all bearing surface combinations have advantages and disadvantages. A patient-based approach is recommended, balancing the risks of different options against an individual’s functional demands.

Cite this article: Bone Joint J 2014;96-B:147–56.

Fracture of a ceramic component in total hip replacement is a rare but potentially catastrophic complication. The incidence is likely to increase as the use of ceramics becomes more widespread. We describe such a case, which illustrates how inadequate initial management will lead to further morbidity and require additional surgery. We present the case as a warning that fracture of a ceramic component should be revised to another ceramic-on-ceramic articulation in order to minimise the risk of further catastrophic wear.

Treatment for osteoarthritis (OA) has traditionally focused on joint replacement for end-stage disease. An increasing number of surgical and pharmaceutical strategies for disease prevention have now been proposed. However, these require the ability to identify OA at a stage when it is potentially reversible, and detect small changes in cartilage structure and function to enable treatment efficacy to be evaluated within an acceptable timeframe. This has not been possible using conventional imaging techniques but recent advances in musculoskeletal imaging have been significant. In this review we discuss the role of different imaging modalities in the diagnosis of the earliest changes of OA. The increasing number of MRI sequences that are able to non-invasively detect biochemical changes in cartilage that precede structural damage may offer a great advance in the diagnosis and treatment of this debilitating condition.

Cite this article: Bone Joint J 2013;95-B:738–46.