Objectives

Opening wedge high tibial osteotomy (HTO) is an established surgical procedure for the treatment of early-stage knee arthritis. Other than infection, the majority of complications are related to mechanical factors – in particular, stimulation of healing at the osteotomy site. This study used finite element (FE) analysis to investigate the effect of plate design and bridging span on interfragmentary movement (IFM) and the influence of fracture healing on plate stress and potential failure.

1. The results of posterior spinal fusion for paralytic scoliosis in 118 patients have been reviewed after growth had finished. The criteria for skeletal maturity were both clinical and radiological, with emphasis on ossification of the iliac apophyses. 2. The age of onset of anterior poliomyelitis and the age at which scoliosis was first noticed, as well as the extent of the muscle weakness and the curve patterns, all have a bearing on the severity of the deformity and the indication for operative treatment. 3. The method of treatment including operation is described and the complications detailed. The use of a tibial strut has now been abandoned and Harrington instrumentation has become routine. 4. There were five deaths in the series, three early and two late. 5. The difference in height, changes in respiratory function and eventual functional capacity have been analysed

1. Forty-eight paralytic dislocations of the hip have been studied and twenty-seven operations for correction of valgus deformity of the femoral neck have been done. 2. The differing features of dislocations occurring in poliomyelitis, cerebral palsy and meningomyelocoele are considered in relation to management after operation. 3. Early recognition of subluxation is essential to a successful varus osteotomy. An angle of 105 degrees rather than the 120 degrees previously recommended is advisable for children under the age of five. 4. Redislocation is most likely to occur in meningomyelocoele in which muscular imbalance is greatest, and in later cases where the acetabulum has become shallow by growth without the femoral head within it. It has not occurred as a late complication after weight bearing has been established, from a recurrence of valgus deformity

1. Avascular necrosis of the bony epiphysis or necrosis of the articular cartilage of the hip joint–without bony necrosis–can occur after a slipped upper femoral epiphysis. 2. In avascular necrosis of the bony epiphysis the prognosis depends upon the degree of revascularisation that occurs and upon survival of the articular cartilage. The articular cartilage can survive and a good functioning hip result especially if aided by mobilisation without weight bearing. 3. The prognosis after necrosis of the articular cartilage is poor. This complication occurs more often when conservative treatment is used. 4. A certain number of hips will show poor results no matter what treatment is used. 5. Nutrition of the articular cartilage is probably by the synovial fluid. 6. Strong traction may damage the soft-tissue structure of the hip joint. 7. It is not advisable to perform an osteotomy soon after a slip of the epiphysis. It is better to wait until good function is assured in the joint

Objectives

This study reports on a secondary exploratory analysis of the early clinical outcomes of a randomised clinical trial comparing robotic arm-assisted unicompartmental knee arthroplasty (UKA) for medial compartment osteoarthritis of the knee with manual UKA performed using traditional surgical jigs. This follows reporting of the primary outcomes of implant accuracy and gait analysis that showed significant advantages in the robotic arm-assisted group.

The results of conventional hip replacement in young patients with osteoarthritis have not been encouraging even with improvements in the techniques of fixation and in the bearing surfaces. Modern metal-on-metal hip resurfacing was introduced as a less invasive method of joint reconstruction for this particular group. This is a series of 446 hip resurfacings (384 patients) performed by one of the authors (DJWM) using cemented femoral components and hydroxyapatite-coated uncemented acetabular components with a maximum follow-up of 8.2 years (mean 3.3). Their survival rate, Oxford hip scores and activity levels are reviewed. Six patients died due to unrelated causes. There was one revision (0.02%) out of 440 hips. The mean Oxford score of the surviving 439 hips is 13.5. None of the patients were told to change their activities at work or leisure; 31% of the men with unilateral resurfacings and 28% with bilateral resurfacings were involved in jobs that they considered heavy or moderately heavy; 92% of men with unilateral hip resurfacings and 87% of the whole group participate in leisure-time sporting activity. The extremely low rate of failure in spite of the resumption of high level occupational and leisure activities provides early evidence of the suitability of this procedure for young and active patients with arthritis

We have studied 27 tibial prostheses retrieved from knee replacements after 1 to 9 years. In 22 the femoral components were of cobalt-chrome, in five polyacetal. The design of the components gave a nominal contact area of 320 mm2 on each condyle. The tibial component was of high-density polyethylene (HDP) at least 6 mm thick, and not heat-treated. In the metal/HDP prostheses the average wear rate was 0.025 mm/year. The relative wear on the medial and lateral sides was related to the leg axis. None of the retrieved prostheses showed any severe disruption of their surface. The polyacetal/HDP prostheses showed similar wear with a statistically insignificant trend towards slower penetration. We conclude that the rate of wear of HDP in a conforming tibiofemoral bearing with a fixed tibial component at least 6 mm thick and not heat-treated is slow enough to be safe in clinical practice

We report the 12 to 74 month results of our mark I saddle prosthesis after its use as a salvage device for gross loss of pelvic bone stock in 76 patients with failed hip arthroplasties. The implant transmits load between iliac bone and bare polish chrome-cobalt. Our clinical and radiological results indicate that a useful and stable articulation can be achieved in most cases, provided that continued deep infection can be avoided. The appearance of radiological sclerosis at the bearing site in successful cases seems to indicate that significant late migration will not occur. Based on our experience with the mark I prosthesis we have designed and developed a mark II model which has freedom of axial rotation of the saddle. Our early results in 40 cases show a significant improvement over the results which could have been predicted for the mark I device

The purpose of this study was to establish if the Bateman prosthesis functions as a bipolar device moving primarily at the inner metal-on-polyethylene bearing as originally proposed, or as a unipolar hemiarthroplasty moving at the outer metal-on-cartilage surface as has recently been suggested. One hundred hips were examined at one year follow-up; 78 were examined again at two to four years. The replacement was performed for arthritis in 76 hips and for femoral neck fracture in 24. Movement was assessed both with and without weight-bearing. In 80% of the arthritis group the prosthesis functioned as a bipolar hip replacement with movement occurring primarily at the inner metal-on-polyethylene surface. By contrast, in 75% of the fracture group the prosthesis functioned largely as a unipolar device with movement occurring primarily at the outer metal-on-cartilage surface. In all cases examined serially the movement pattern was the same at two to four years as it has been at one year. Clearly, the action of the prosthesis depends on the condition of the acetabular cartilage

Aims

Severe acetabular bone loss and pelvic discontinuity (PD) present particular challenges in revision total hip arthroplasty. To deal with such complex situations, cup-cage reconstruction has emerged as an option for treating this situation. We aimed to examine our success in using this technique for these anatomical problems.

Aims

The primary aim of this study was to define and quantify three new measurements to indicate the position of the greater trochanter. Secondary aims were to define ‘functional antetorsion’ as it relates to abductor function in populations both with and without torsional abnormality.

1. One hundred and eight osteotomies were reviewed with regard to union, and fourteen were found to be ununited. In only one was non-union detected clinically; the others required radiographic demonstration. Tomographs were particularly helpful in confirming non-union. 2. Nine patients with non-union had pain, equal to or worse than before operation. The pain could not be distinguished from that of osteoarthritis of the hip. 3. Six of the patients with non-union needed an operation. Five had cancellous bone grafts followed by union in all except one. 4. The causes of non-union are reviewed. This complication was found to be less frequent in patients above sixty with stiff hips and bony collapse on the radiograph. Horizontal osteotomy with a displacement of not more than one-third of the diameter of the shaft reduced the incidence of non-union. The variable-angle nail-plate provided the best fixation. Traction provided no benefit and increased the incidence of non-union. Weight bearing is best avoided for eight weeks

1. Sixty-five cases of medial fracture of the femoral neck treated by substitution of the head by an acrylic prosthesis have been studied. 2. In general, the long-term clinical results of prosthetic arthroplasty after fresh fractures have been disappointing. The method has given slightly better results in the treatment of old fractures. 3. In view of the almost perfect results obtained after successful Smith-Petersen nailing in the presence of an adequate blood supply to the femoral head, it seems unjustifiable to abandon this principle for immediate substitution with an acrylic femoral head. Nevertheless it is believed that an arthroplasty of this type is justified in fractures seen late, and in fresh subcapital fractures when the fracture is irreducible. If a prosthesis is to be used, more protection for the stump of the neck against the strain of weight bearing is essential; a simple head prosthesis is inadequate, and a head with either a neck extension or an intramedullary prolongation may give better results

From 1969 through 1982, 305 hips in 290 patients had total hip arthroplasty for failed femoral intertrochanteric osteotomy. Of these, we reviewed 215 hips (70.5%) with a minimum follow-up of five years. The results were good or excellent in 79%, but there were technical problems at operation in 23% and a total perioperative complication rate of 11.8%. Late complications occurred in 13.1% including seven late infections (3.2%). At a mean follow-up of ten years, 39 hips had been revised (18.1%), there was probable loosening in 19.5% of stems and 12.6% of cups and possible loosening in 11.4% of stems and 7.2% of cups. The cumulative probability of failure at ten years was 20.6%. We recommend that intertrochanteric osteotomy be advised, planned and executed bearing in mind the possible need for a subsequent total hip arthroplasty, and that screws and plates should be routinely removed soon after union of the osteotomy

Radiographs of 155 Indian children were examined to identify the acetabular changes which occur in Perthes' disease. These changes included osteoporosis of the acetabular roof, irregularity of contour, premature fusion of the triradiate cartilage, hypertrophy of articular cartilage and changes in dimensions. These changes tended to be more marked in older children and when more than half of the femoral epiphysis was involved. Comparison with 25 cases of Perthes' disease from Liverpool showed the same picture. Several of the acetabular changes noted during the active stages were also seen in a series of 24 adult hips after Perthes' disease. Radio-isotope scans of the hips of 27 children with Perthes' disease showed a consistently increased uptake in the acetabulum on the affected side, indicative of a local increase in vascularity and metabolic activity. It was possible to postulate a working model for the pathogenesis of all the acetabular changes. A number of statistical correlations suggest that most of the changes have a bearing on the final outcome

The Oxford Knee, a resurfacing prosthesis with a meniscal bearing, can be used for either bicompartmental or unicompartmental arthritis. The first 103 unicompartmental cases are presented at a mean time since operation of 36 months (range 21 to 56 months). In those cases with surviving arthroplasties, pain was relieved in 96%. The full range of pre-operative flexion was maintained and flexion deformity was improved from a mean of 6.7 to 5.4 degrees. Stability and alignment were restored to normal in nearly all the knees. Absence of the anterior cruciate ligament was associated with a significantly greater incidence of failure. Six failures occurred in 37 knees lacking a normal anterior cruciate ligament (16.2%); three occurred in 63 knees with a normal anterior cruciate ligament (4.8%) (p less than 0.02). Criteria for the future selection of patients have been deduced from our experience. The operation is recommended for knees with severe unicompartmental osteoarthritis in which all the ligaments are still intact

1. The rate of non-union of 100 intertrochanteric osteotomies of the McMurray type, with internal fixation, is reported. One in five was not united one year after operation. The criteria of union are discussed. 2. The patient's disability in twelve ununited osteotomies has been assessed, and related to the mobility of the osteotomy. 3. The factors which prejudice union have been analysed. The principal cause of non-union appeared to be the varus angulation strain on a varus osteotomy displaced medially more than half the diameter of the bone. Obliquity inwards and upwards of the osteotomy was a contributory factor. The types of internal fixation used, the use of external splintage and the period of protected weight bearing with crutches did not appear to be related to the rate of union. 4. It is concluded that marked inward displacement of the osteotomy, combined with either obliquity of the osteotomy or a varus position, prejudices union; that the use of this technique is unfounded in principle and not supported empirically; and that displacement should be eschewed to avoid this complication of intertrochanteric osteotomy in the treatment of osteoarthritis of the hip

Three elderly sibling dwarfs are reported from a large and otherwise normal family. Their condition is an unusual and irregular form of cartilaginous defect, combined with club-feet, and bearing some resemblance to the Morquio type. A brief consideration of the literature of the generahised developmental bony syndromes shows confusion of thought and nomenclature. A plea is therefore made for simplification and a rational and simple grouping of these conditions is attempted. It seems particularly desirable that many confusing names for particular syndromes should be scrapped (for example, dyschondroplasia, chondro-osteodystrophy), although quite evidently the terms achondroplasia and osteogenesis imperfecta must remain because of their long-standing and general usage. Incidentally I have suggested elsewhere (Jackson 1951) that the name cleido-cranial dysostosis should be dropped, because it tends to lead the investigator away from the clinically more important lesions in the teeth and the cartilage bones of the pelvis and legs. It seems reasonable to confine the nomenclature of these various syndromes to the names used in the above classification, or something on those lines

Despite its intrinsic ability to regenerate form and function after injury, bone tissue can be challenged by a multitude of pathological conditions. While innovative approaches have helped to unravel the cascades of bone healing, this knowledge has so far not improved the clinical outcomes of bone defect treatment. Recent findings have allowed us to gain in-depth knowledge about the physiological conditions and biological principles of bone regeneration. Now it is time to transfer the lessons learned from bone healing to the challenging scenarios in defects and employ innovative technologies to enable biomaterial-based strategies for bone defect healing. This review aims to provide an overview on endogenous cascades of bone material formation and how these are transferred to new perspectives in biomaterial-driven approaches in bone regeneration.

Cite this article: T. Winkler, F. A. Sass, G. N. Duda, K. Schmidt-Bleek. A review of biomaterials in bone defect healing, remaining shortcomings and future opportunities for bone tissue engineering: The unsolved challenge. Bone Joint Res 2018;7:232–243. DOI: 10.1302/2046-3758.73.BJR-2017-0270.R1.