The aim of this study was to assess the effect of injecting genetically engineered chondrocytes expressing transforming growth factor beta 1 (TGF-β1) into the knees of patients with osteoarthritis. We assessed the resultant function, pain and quality of life. . A total of 54 patients (20 men, 34 women) who had a mean age of 58 years (50 to 66) were blinded and randomised (1:1) to receive a single injection of the active treatment or a placebo. We assessed post-treatment function, pain severity, physical function, quality of life and the incidence of treatment-associated adverse events. Patients were followed at four, 12 and 24 weeks after injection. At final follow-up the treatment group had a significantly greater improvement in the mean International Knee Documentation Committee score than the placebo group (16 points; -18 to 49, vs 8 points; -4 to 37, respectively; p = 0.03). The treatment group also had a significantly improved mean visual analogue score at final follow-up (-25; -85 to 34, vs -11 points; -51 to 25, respectively; p = 0.032). Both cohorts showed an improvement in Western Ontario and McMaster Osteoarthritis Index and Knee Injury and Osteoarthritis Outcome Scores, but these differences were not statistically significant. One patient had an anaphylactic reaction to the preservation medium, but recovered within 24 hours. All other adverse events were localised and resolved without further action. . This technique may result in improved clinical outcomes, with the aim of slowing the degenerative process, leading to improvements in pain and function. However, imaging and direct observational studies are needed to verify cartilage regeneration. Nevertheless, this study provided a sufficient basis to proceed to further clinical testing. Cite this article: Bone Joint J 2015;97-B:924–32

Four methods of surgical treatment of chondromalacia patellae have been evaluated after periods ranging from two to thirty years (average seven years), to discover the success rate, complications and indications for each. A total of 140 operations had been performed in 98 patients. Overall, satisfactory results were achieved in 25 per cent after forty shavings of the patellar cartilage, 35 per cent after twenty cartilage excisions and drilling of the subchondral bone, 60 per cent after twenty medial transfers of the patellar tendon and 77 per cent after sixty patellectomies. Thirty-four primary patellectomies gave 82 per cent satisfactory results compared with 62 per cent after twenty-six patellectomies performed after a previously unsuccessful operation. The results were worst in patients below twenty years of age especially women and in those with Grade IV changes in the patellar cartilage. Weakness of the quadriceps after any procedure predisposed to an unsatisfactory result. Extensive late radiological degenerative changes in the knee were not seen. On the basis of the results in this report, patellar tendon transfer is recommended in adolescents and athletes with Grade I, II or III changes in the patellar cartilage. In adults over twenty years of age with Grade I and II changes cartilage excision and drilling is satisfactory. In adults with Grade III and adults or adolescents with Grade IV changes patellectomy is the treatment of choice

Aims

Chondrosarcoma is the second most common primary sarcoma of bone: conventional chondrosarcoma accounts for 85% of all cases. Conventional chondrosarcoma may be central or peripheral. Most studies group central and peripheral chondrosarcomas together, although there is growing evidence that their clinical behaviour and prognosis differ. The aims of this study were to analyze any differences in characteristics between central and peripheral chondrosarcomas and to investigate the incidence and role of different syndromes.

The experiments were performed to answer three main questions. These and our answers may be summarised as follows. What is the precise mechanism of healing of a raw bony surface in a joint? What cells are involved? Where do they originate?—In all the implant experiments and in the control series the fundamental mechanism of healing was similar. 1. A massive proliferation of fibroblasts occurred from the cut periosteum, from the cut joint capsule, and to a lesser extent from the medullary canal. 2. Fibroblasts grew centripetally in the first few weeks after operation, attempting to form a "fibroblast cap" to the cut bone end. 3. Fibroblasts of this cap near the cut bone spicules metamorphosed to become prechondroblasts, chondroblasts laying down cartilage matrix, and hypertrophied (alkaline phosphatase-secreting) chondrocytes lying in a calcified matrix. 4. This calcified cartilage matrix was invaded by dilated capillaries probably bearing osteoblasts which laid down perivascular (endochondral) bone. 5. Some of the cells of projecting bone spicules died and their matrix was eroded in the presence of many osteoclasts. 6. In the control experiments of simple excision of the radial head new bone was produced at the periphery only by processes (3) and (4). This sealed off the underlying peripheral cortical bone from the superficially placed peripheral articular surface of fibrocartilage. At about a year from operation the central portion of the articular surface was still formed of bare bone, or of bone spicules covered by a thin layer of irregularly arranged collagen fibres. The opposite capitular articular cartilage was badly eroded. Does the introduction of a dead cartilage implant over the raw bone end affect in any way the final constitution of the new articular surface?—In the implant experiments the new bone produced by processes (3) and (4) formed, after about a year, a complete cortical plate which entirely sealed off the cut end of the radius and left a superficially placed articular covering of smooth fibrocartilage, closely resembling a normal joint surface. The opposite capitular articular surface was normal. What is the final fate of such an implant?—Whale cartilage implants underwent replacement by fibroblasts and collagen fibres, and took about nine months to disappear. The cartilage of fixed autotransplants and homotransplants underwent similar gradual replacement, and took about the same time in each case. The dead bone, implanted in association with the cartilage in both cases, acted as a nidus for hyaline cartilage production by chondrocytes derived from fibroblasts. This cartilage underwent endochondral ossification. This observation suggests that induction by non-cellular osseous material is a factor in chondrification and ossification. All the implants functioned as temporary articular menisci or in some cases as temporary radial articular surfaces. They were always replaced by a permanent fibrocartilaginous meniscus, or a fibrocartilaginous articular surface. An implant did, in fact, always act as a temporary protecting cap and mould for the subjacent growth offibroblasts which was necessary for the production of a satisfactory new joint surface

Osteoarthritis, as seen in the hip, is a disease which eventually embraces all the tissues of the joint but begins as a reaction of the juxta-chondral blood vessels to a degeneration of the articular cartilage; this reaction results in a hyperaemia of the bone. To our surprise we found that daily use preserves rather than "wears out" articular cartilage; indeed inadequate use is the commonest cause of cartilage degeneration and ensuing vascular invasion. To this factor are added the effects of excessive pressure in the many patients who require surgical treatment for advanced osteoarthritis of a hip the seat of some anatomical incongruity. This etiology based on cartilage suffering does not exclude, but indeed explains, the osteoarthritis implanted on joints of a normal shape which have been previously affected by acute or chronic inflammation or by hormonal dysfunction, such as acromegalic osteoarthritis. The stimulus to vessel growth and invasion is the same in all these cases—namely cartilage damage. Once the vessels have entered the cartilage the bone and marrow of the osteophyte are inevitably laid down. What is so damaging in osteoarthritis seems to be not the degeneration of the cartilage but the vigorous and persistent attempt at repair, an attempt which aggravates the already disordered function of the joint not only by osteophyte formation but by the hypervascularity which weakens the structure of the bone beyond the point where it can carry its increased load. The collapse that follows provokes further reparative efforts with the same deplorable results. The osteoarthritic process thus appears to be an attempt to transform a decaying joint into a youthful one and for this, as in the miraculous rejuvenation depicted in Goethe's Faust, a high price must ultimately be paid

Aims

The patient-acceptable symptom state (PASS) is a level of wellbeing, which is measured by the patient. The aim of this study was to determine if the proportion of patients who achieved an acceptable level of function (PASS) after medial unicompartmental knee arthroplasty (UKA) was different based on the status of the anterior cruciate ligament (ACL) at the time of surgery.

As our understanding of hip function and disease improves, it is evident that the acetabular fossa has received little attention, despite it comprising over half of the acetabulum’s surface area and showing the first signs of degeneration. The fossa’s function is expected to be more than augmenting static stability with the ligamentum teres and being a templating landmark in arthroplasty. Indeed, the fossa, which is almost mature at 16 weeks of intrauterine development, plays a key role in hip development, enabling its nutrition through vascularization and synovial fluid, as well as the influx of chondrogenic stem/progenitor cells that build articular cartilage. The pulvinar, a fibrofatty tissue in the fossa, has the same developmental origin as the synovium and articular cartilage and is a biologically active area. Its unique anatomy allows for homogeneous distribution of the axial loads into the joint. It is composed of intra-articular adipose tissue (IAAT), which has adipocytes, fibroblasts, leucocytes, and abundant mast cells, which participate in the inflammatory cascade after an insult to the joint. Hence, the fossa and pulvinar should be considered in decision-making and surgical outcomes in hip preservation surgery, not only for their size, shape, and extent, but also for their biological capacity as a source of cytokines, immune cells, and chondrogenic stem cells.

Cite this article: Bone Joint Res 2020;9(12):857–869.

The December 2013 Research Roundup. 360 . looks at: Inflammation implicated in FAI; Ponseti and effective teaching; Unicompartmental knee design and tibial strain; Bisphosphonates and fracture healing; Antibiosis in cement; Zoledronic acid improves primary stability in revision?; Osteoporotic fractures revisited; and electroarthrography for monitoring of cartilage degeneration

The June 2013 Research Roundup. 360 . looks at: a contact patch to rim distance and metal ions; the matrix of hypoxic cartilage; CT assessment of early fracture healing; Hawthornes and radiographs; cardiovascular mortality and fragility fractures; and muscle strength decline preceding OA changes

The high prevalence of osteoarthritis (OA), as well as the current lack of disease-modifying drugs for OA, has provided a rationale for regenerative medicine as a possible treatment modality for OA treatment. In this editorial, the current status of regenerative medicine in OA including stem cells, exosomes, and genes is summarized along with the author’s perspectives. Despite a tremendous interest, so far there is very little evidence proving the efficacy of this modality for clinical application. As symptomatic relief is not sufficient to justify the high cost associated with regenerative medicine, definitive structural improvement that would last for years or decades and obviate or delay the need for joint arthroplasty is essential for regenerative medicine to retain a place among OA treatment methods.

Cite this article: Bone Joint Res 2021;10(2):134–136.

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. Experiments have been carried out in lambs to determine the source of nutrition of the joint cartilage of an immature animal. A wedge of bone with its overlying cartilage was removed from the knee joint and then replaced in its original position, so that the bone was infarcted but the cartilage remained in normal relationship with the joint. 2. In these circumstances degeneration of the cartilage occurred and proliferation ceased until revascularisation of the bone was established. 3. It is therefore concluded that growing cartilage derives a significant part of its nutrition from the underlying bone. The possibility that it also receives a contribution from synovial fluid has not been excluded

The February 2014 Foot & Ankle Roundup. 360 . looks at: optimal medial malleolar fixation; resurfacing in the talus; predicting outcome in mobility ankles; whether mal-aligned ankles can be successfully replaced; cartilage colonisation in bipolar ankle grafts; CTs and proof of fusion; recalcitrant Achilles tendinopathy; and recurrent fifth metatarsal stress fractures

1. Osmium tetroxide and nitrogen mustard were injected into normal adult rabbit joints. Within one week widespread chondrocyte necrosis had occurred as evidenced by electron microscopic examination and radioactive proline uptake autoradiography. 2. Initially, the cartilage matrix was intact but three to seven months later the cartilage surface began to disintegrate. 3. These studies indicate that osmium tetroxide and nitrogen mustard are unsuitable agents for chemical synovectomy. 4. They also indicate that there may be a long latent period between cartilage cell death and cartilage destruction, and that the evaluation of any agent for chemical synovectomy must take this into consideration

The February 2014 Research Roundup. 360 . looks at: blood supply to the femoral head after dislocation; diabetes and hip replacement; bone remodelling over two decades following hip replacement; sham surgery as good as arthroscopic meniscectomy; distraction in knee osteoarthritis; whether joint replacement prevent cardiac events; tranexamic acid and knee replacement haemostasis; cartilage colonisation in bipolar ankle grafts; CTs and proof of fusion; atorvastatin for muscle re-innervation after sciatic nerve transection; microfracture and short-term pain in cuff repair; promising early results from L-PRF augmented cuff repairs; and fatty degeneration in a rodent model

We studied cartilage degeneration in 45 canine acetabula after implantation of prostheses with articulating surfaces of low-temperature isotropic (LTI) pyrolytic carbon, cobalt-chromium-molybdenum alloy and titanium alloy for periods ranging from two weeks to 18 months. Gross specimens and histological sections were compared with the nonoperated (control) acetabulum of the same animal. Cartilage articulating with LTI pyrolytic carbon exhibited significantly lower levels of gross wear, fibrillation, eburnation, glycosaminoglycan loss, and subchondral bone change than with metallic surfaces. Survivorship analysis showed a 92% probability of survival for cartilage articulating with LTI pyrolytic carbon at 18 months, as compared to only a 20% probability of survival for cartilage articulating with either of the metallic alloys

The acute childhood diseases haematogenous staphylococcal osteomyelitis and septic arthritis were studied concurrently using avian models which closely resemble the human diseases. Ultrastructural studies during the initial stages of bone and joint infection showed that adherence of bacteria to cartilage, bacterial proliferation, cartilage destruction and subsequent bacterial spread along the vascular channels within cartilage were common to both disease processes. Histological studies revealed that transphyseal blood vessels were present in the growing chickens and were a likely explanation for the frequency of the concurrence of acute osteomyelitis and adjacent joint infection following intravenous injection of bacteria. Transphyseal vessels provide a direct connection between the growth plate (physis) and epiphyseal cartilage supplying a route for bacteria to spread from an osteomyelitic focus in the metaphysis to the epiphysis and subsequently to the joint lumen

Stem cells are a key component of regenerative medicine strategies. Particular areas of musculoskeletal application include cartilage and bone regeneration in arthritis and trauma. There are several types of stem cell and this article will focus on the adult derived cells. The review includes current issues and future developments