Limb salvage is now customary in the treatment of primary bone tumours. The proximal tibia is a frequent site for these neoplasms but reconstruction, especially in children, is a formidable challenge. We reviewed 20 children with extendible replacements of the proximal tibia, all with a minimum follow-up of five years. Five died from their disease and, of the remaining 15, four had above-knee amputations for complications. Infection occurred in seven patients; in five it was related to the lengthening procedure. Aseptic loosening is inevitable in the younger children and only two have avoided a revision, amputation or other major complication; both were aged 12 years at the time of the initial surgery. Despite this, 11 children are alive with a functioning leg and a mean Musculoskeletal Tumour Society functional score of 83%. The lengthening mechanisms used in our series required extensive open operations. We are now using a simpler, minimally invasive, technique which we hope will decrease the incidence of complications. At present, the use of extendible prostheses of the proximal tibia remains an experimental procedure

Aims

The aim of this study was to report the clinical, functional and radiological outcomes of children and adolescents with tibial fractures treated using the Ilizarov method.

Aims

The objective of this study was to compare early postoperative functional outcomes and time to hospital discharge between conventional jig-based total knee arthroplasty (TKA) and robotic-arm assisted TKA.

From 1987 to 1991, we treated 53 patients with 54 fractures of the acetabulum by reconstruction through a posterior or an extended iliofemoral surgical approach. For prophylaxis against heterotopic ossification we used perioperative irradiation and indomethacin. Indomethacin was given as daily doses of 25 mg started within 24 hours of operation and continued for four weeks. Irradiation was by either 1200 cGy in three daily doses or by a single 700 cGy dose on the first postoperative day. All patients were followed for at least one year postoperatively and the severity of heterotopic ossification was recorded using the Brooker classification and correlated with hip mobility. The combination therapy proved very effective; 44 fractures showed no heterotopic ossification and ten showed Brooker class I. The functional results were good and there were no complications of this therapy. Irradiation with 1200 cGy did not appear to offer any therapeutic advantage over the 700 cGy dose

We treated 39 knees with chronic deficiency of the anterior cruciate ligament by reconstruction using the ABC carbon and polyester prosthetic ligament; 31 (79.5%) were reviewed at an average follow-up of 34 months. There had been four complete failures requiring revision. The remaining 27 were studied in detail. On the Lysholm rating, only 11 knees (41%) had good results with a score of over 76. The mean anterior drawer movement was reduced from 7.6 mm before operation to 5.8 mm at review. The mean difference from the opposite uninjured knee was 3.9 mm before operation, 1 mm (in 21 patients) at mean follow-up of 7.4 months and 2.5 mm (in 27 patients) at 34 months, indicating progressive loss of effect. In our opinion the results are unsatisfactory: we do not recommend the use of this prosthetic ligament

Objectives

The Precice nail is the latest intramedullary lengthening nail with excellent early outcomes. Implant complications have led to modification of the nail design. The aim of this study was to perform a retrieval study of Precice nails following lower-limb lengthening and to assess macroscopical and microscopical changes to the implants and evaluate differences following design modification, with the aim of identifying potential surgical, implant, and patient risk factors.

We compared two methods of reconstruction of the abductor mechanism in 15 patients after prosthetic replacement of the upper femur, to assess abductor strength and function. Six patients in group I had direct fixation of the gluteus medius tendon and a segment of the original bone to the prosthesis. Nine patients in group 2 had the abductor tendon fixed to the iliotibial band. We assessed clinical function, isometric muscle strength and muscle cross-sectional area for each patient. The patients in group 1 had better clinical and functional results (p = 0.059), with average peak torques for hip abduction of 92% of that in the non-operated leg in group 1, and of 57% in group 2. Group 1 had a mean muscle cross-sectional area of 69% and a mean value of strength per cross-sectional area of 134% when compared with the control side. The respective values for group 2 were 52% and 91%. Direct fixation of the abductor muscles to the prostheses gave improved function and higher isometric abductor muscle force

We have assessed the long-term results after operative and non-operative treatment of undisplaced and displaced calcaneal fractures. At a mean of 6.5 years, we reviewed 70 patients with a calcaneal fracture who were divided into four groups: group 1, 18 patients with undisplaced fractures and a normal Böhler’s angle (BA) who had been treated non-operatively; group 2, 23 with intra-articular fractures and a BA < 10° who had been treated non-operatively; group 3, 13 with intra-articular fractures and a BA > 10° who had been treated surgically; and group 4, 16 with intra-articular fractures and a BA < 10° who had been treated surgically. The results were assessed by a clinical score considering pain, return to work, return to physical activity, change in shoe-wear and the requirement for subtalar arthrodesis. Patients with undisplaced calcaneal fractures had a good outcome. Those with displaced fractures treated surgically who presented at follow-up with a BA > 10° had a satisfactory functional outcome and those with displaced fractures who had non-operative treatment had a poor outcome. The poorest outcome was consistently seen in patients who were treated operatively without restoration of BA. Open reduction and internal fixation of intra-articular calcaneal fractures can only be expected to benefit those patients in whom nearly anatomical reconstruction is obtained

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.

Aims

The aim of this study was to describe the technique of distraction osteogenesis followed by arthrodesis using internal fixation to manage complex conditions of the ankle, and to present the results of this technique.

We performed CT to investigate how treatment may modify the basic skeletal pathology of congenital club foot. Two homogenous groups of patients treated by one of the authors (EI) or under his supervision were studied. The first included 32 patients with 47 club feet reviewed at a mean age of 25 years and treated by manipulation, application of toe-to-groin plaster casts and an extensive posteromedial release. The second included 32 patients with 49 club feet reviewed at a mean age of 19 years and treated by the Ponseti manipulation technique, application of toe-to-groin plaster casts and a limited posterior release. At follow-up the shape of the subtalar, talonavicular and calcaneocuboid joints was found to be altered in many feet in both groups. This did not appear to be influenced significantly by the type of treatment performed. Correction of the heel varus and the increased declination angle of the neck of the talus was better in the club feet of the second group, whereas reduction of the medial subluxation of the navicular was better in the first. There was a marked increase in the external ankle torsion angle in the first group and a moderate increase of this angle in the second group, in which medial subluxation of the cuboid on the anterior apophysis of the calcaneum was always corrected. Equinus was corrected in both groups but three-dimensional CT reconstruction of the whole foot showed that cavus, supination and adduction deformities were corrected much better in the second group

1. After limb injuries with loss of skin and subcutaneous tissue, full-thickness skin flaps afford the most satisfactory cover. It is particularly important to replace unstable and scarred skin before attempting bone reconstruction and similar operations. 2. In the leg and foot, full-thickness skin cover is conveniently obtained by the cross-leg flap technique. The blood supply of such flaps is considered and the technique of operation is described. Free excision of avascular scar tissue is essential. 3. "Delayed transfer" of the flap is advisable unless conditions are favourable; two methods are considered. 4. Immobilisation in plaster is the most satisfactory method of fixation of the limbs after attachment of the flap. Muscle exercises are performed throughout the period of treatment in order to minimise joint stiffness and shorten convalescence. 5. The cross-leg flap technique should not usually be used in children, young women, or the aged and mentally infirm. Contra-indications include arthritis of the knee and hip joints because there is danger of joint stiffness. 6. Vascular complications of cross-leg skin grafting are discussed

In nine patients of median age 34 years who had sustained an amputation of the thumb at a median 24 (5 to 131) months previously, we lengthened the first metacarpal by 30 (17 to 36) mm. Seven amputations had been through the proximal phalanx and two through the metacarpal. The first two patients had autogenous grafting at a second stage, but the other seven had callotasis alone. In these patients the external fixators were removed at a median 189 (115 to 271) days after osteotomy. In six cases the adductor pollicis tendon was transferred proximally and the first web deepened. There was late fracture or palmar flexion of the callus in five patients, but this required further surgery in only one. Treatment was complete at 326 (140 to 489) days after osteotomy. The extended thumb retained its sensitivity; both grasp and key-pinch strength were satisfactory and only one patient felt that the result did not warrant the long course of treatment. Metacarpal lengthening by this method is a prolonged procedure, but provides a valuable alternative to more complex reconstructions

We reviewed 50 capitellocondylar elbow replacements performed by the lateral approach in 42 rheumatoid patients, at a median follow-up of three years. There were two major and 17 minor complications; 18 were early and one was late. Eight elbows required reoperation: soft-tissue surgery was performed in seven and prosthesis removal in one because of a deep infection. There were few problems of instability, but one patient sustained a traumatic dislocation which was stabilised after ligament reconstruction. Wound healing was delayed in two of five elbows which had been immobilised postoperatively for only five days, but healing was rapid in 45 elbows immobilised for 12 days. There was transient ulnar-nerve palsy postoperatively in 11 patients, with permanent palsy in three. All elbows were painfree or only slightly painful at follow-up; 49 were stable and 43 had a range of motion sufficient for activities of daily living. Radiological loosening of the humeral component was suspected in one asymptomatic elbow. The lateral approach is recommended for use with the capitellocondylar type of prosthesis in rheumatoid elbows with reasonably well-preserved bone stock

Objectives

Bone fracture healing is regulated by a series of complex physicochemical and biochemical processes. One of these processes is bone mineralization, which is vital for normal bone development. Phosphatase, orphan 1 (PHOSPHO1), a skeletal tissue-specific phosphatase, has been shown to be involved in the mineralization of the extracellular matrix and to maintain the structural integrity of bone. In this study, we examined how PHOSPHO1 deficiency might affect the healing and quality of fracture callus in mice.

We studied the morphometry of 35 femora from 31 female patients with developmental dysplasia of the hip (DDH) and another 15 from 15 age- and sex-matched control patients using CT and three-dimensional computer reconstruction models. According to the classification of Crowe et al 15 of the dysplastic hips were graded as class I (less than 50% subluxation), ten as class II/III (50% to 100% subluxation) and ten as class IV (more than 100% subluxation). The femora with DDH had 10 to 14° more anteversion than the control group independent of the degree of subluxation of the hip. In even the most mildly dysplastic joints, the femur had a smaller and more anteverted canal than the normal control. With increased subluxation, additional abnormalities were observed in the size and position of the femoral head. Femora from dislocated joints had a short, anteverted neck associated with a smaller, narrower, and straighter canal than femora of classes I and II/III or the normal control group. We suggest that when total hip replacement is performed in the patient with DDH, the femoral prosthesis should be chosen on the basis of the severity of the subluxation and the degree of anteversion of each individual femur

It has been suggested that the endurance of cemented femoral reconstructions in total hip arthroplasty is affected by the creep of acrylic cement, but it is not known to what extent cement creeps under loading conditions in vivo, or how this affects load transfer. We have simulated the long-term creep properties of acrylic cement in finite-element models of femoral stem constructs and analysed their effects. We investigated whether subsidence rates measured in vivo could be explained by creep of acrylic cement, and if polished, unbonded, stems accommodated creep better than bonded stems. Our findings showed that polished prostheses subsided only about 50 μm as a result of cement creep. The long-term prosthetic subsidence rates caused by creep of acrylic cement are therefore very small and do not explain the excessive migration rates which have sometimes been reported. Cement creep did, however, relax cement stresses and create a more favourable stress distribution at the interfaces. These trends were found around both the bonded and unbonded stems. Our results did not confirm that polished, unbonded, stems accommodated creep better than bonded stems in terms of cement and interface stress patterns

Distraction osteogenesis (callotasis) has been widely used in patients with limb-length inequality or massive bone defects. This procedure, however, may be associated with a high incidence of physical and psychosocial complications. Callotasis telescoping on a locked intramedullary nail has been used to shorten the period of external fixation. Little attention has been given to the use of locked intramedullary nails in the treatment of complications after callotasis. Between 1990 and 1999, we used locked intramedullary nailing in 27 patients for the treatment of complications after distraction osteogenesis. There were 17 men and ten women with a mean age of 33.2 years (16 to 66). The nail was inserted at a mean of 3.4 weeks (0 to 15) after removal of the external fixator. Simultaneous autogenous bone grafting and soft-tissue reconstruction were also undertaken in seven and two patients, respectively. There was consolidation of the callus or docking site in all patients at a mean of 6.4 months (2 to 14) after surgery. The mean shortening of the callus was 0.7 cm (0 to 2.5). Two patients had infection at the site of a distal screw which resolved after removal of the nail. In 17 patients the nail was removed at a mean of 26 months after its insertion. Locked intramedullary nails are useful in treating complications after distraction osteogenesis in skeletally mature patients. The risk of infection should be borne in mind