Carbon-carbon composite nail for intramedullary osteosynthesis in rats with experimental osteoporosis

Background. In Ukraine, there has recently been an increase in the number of limb bone fractures among the population, in particular, due to increase in the number of elderly people, which is associated with the development of age-related osteoporosis and fragility of bones. Therefore, the use of artificial implants in traumatology is becoming increasingly important. The search for new bioinert and biodegradable materials, that are capable of providing rapid fracture consolidation and do not require repeated surgical intervention, continues. Objective. To elaborate a model for the research of using carbon-carbon composite nail for intramedullary osteosynthesis in laboratory rats with fractures of femur and tibia in norm and with experimental osteoporosis. Methods. The work investigated the lower limbs of 6 groups of Wistar rats. The first part of the study involved 4 groups of rats with modeled tibial fracture with subsequent osteosynthesis in norm and with experimental osteoporosis. The second part of the research included two groups of laboratory rats with modeled femur fracture. In both parts we used metal injection needle, as well as carbon-carbon composite nail for osteosynthesis. Results. All animals underwent surgery well, stepped on the injured limb. X-ray examination after the osteosynthesis demonstrated satisfactory reposition of the fragments. One month after modeled fracture in rats with experimental osteoporosis a violation of the normal consolidation of the fracture was observed, especially in the group where carbon-carbon composite nails were used for osteosynthesis. Further, until the 180th day after the surgery there were no peculiarities, function of the limbs was restored, mainly without expressed angular deformities. Conclusion. The above mentioned model was successfully elaborated for the research of using carbon-carbon composite nail for intramedullary osteosynthesis in laboratory rats with fractures of femur and tibia in norm and with experimental osteoporosis.

Safe corridors for external skeletal fixator pin placement in feline long bones

Objectives External skeletal fixation is an established technique in cats for biological fixation of long bone fractures, stabilisation of the joints, and treatment of shearing injuries and angular deformities. As appropriate and accurate pin insertion is imperative for a successful outcome, knowledge of topographic anatomy and areas that are safe (safe corridors) for pin placement is integral to successful surgery. At present, however, safe corridors have not been determined fully in feline orthopaedics, with surgeons having to rely on knowledge based on canine orthopaedics. This study was performed to determine safe corridors for pin placement in feline long bones. Methods The limbs of six feline cadavers were frozen. Only limbs with no history of orthopaedic conditions were used. Transverse sections through the limbs were examined, and anatomical structures were determined in relation to the bone. These structures were compared with those of the contralateral limbs, which were dissected for topographic assessment. Safe corridors were defined as topographic areas where no vital structures, muscles or joints were present. Results Examination of the humerus revealed safe corridors at its proximal craniolateral aspect and on the medial and lateral humeral condyles. Safe corridors of the antebrachium were identified on the lateral aspect of the olecranon, the distal two-thirds of the medial antebrachium and the distal third of the lateral antebrachium. Safe corridors in the femur consisted of a small area lateral to and just below the major trochanter, and on the medial and lateral femoral condyles. Evaluation of the tibia revealed safe corridors on the medial aspect of the entire tibia, the cranial aspect of the proximal tibia on the tibial crest and the area just proximal to the lateral malleolus. Conclusions and relevance Safe corridors for pin placement during external skeletal fixation in feline limbs differed from those in canine limbs. Knowledge of canine anatomy may be inapplicable to pin placement in feline limbs undergoing external skeletal fixation.

Growth modulation with tension-band plates for the correction of paediatric lower limb angular deformity: current concepts and indications for a rational use

Growth modulation (GM) with tension-band plates (TBPs) by tethering part of the growth plate is an established technique for the correction of angular deformities in children, and it has increasingly supplanted more invasive osteotomies. Growth modulation with TBPs is a safe and effective method to correct a variety of deformities in skeletally immature patients with idiopathic and pathological physes. The most common indication is a persistent deformity in the coronal plane of the knee exceeding 10°, with anterior and/or lateral joint pain, patellofemoral instability, gait disturbance, or cosmetic concerns. GM has also shown good results in patients with fixed flexion deformity of the knee and ankle valgus. This paper reviews the history of the procedure, current indications, and recent advances underlying physeal manipulation with TBPs. Cite this article: EFORT Open Rev 2021;6:658-668. DOI: 10.1302/2058-5241.6.200098

Tension band plates have greater risks of complications in temporary epiphysiodesis

Purpose This study aimed to compare the efficacy of decreasing leg-length discrepancy (LLD) and postoperative complications between tension band plates (TBP) and percutaneous transphyseal screws (PETS). Methods This retrospective study reviewed LLD patients who underwent temporary epiphysiodesis at the distal femur and/or proximal tibia from 2010 to 2017 (minimum two years follow-up). Efficacy of decreasing LLD was assessed one and two years postoperatively. Complications were classified with the modified Clavien-Dindo-Sink complication classification system. Knee deformities were assessed by percentile and zone of mechanical axis across the tibial plateau. Results In total, 53 patients (25 boys, 28 girls) underwent temporary epiphysiodesis (mean age, 11.4 years). The efficacy of decreasing LLD at two years between the TBP (n = 38) and PETS (n = 15) groups was comparable. Seven grade III complications were recorded in six TBP patients and in one PETS patient who underwent revision surgeries for knee deformities and physis impingement. Four grade I and two grade II complications occurred in the TBP group. The mechanical axis of the leg shifted laterally in the PETS group and medially in the TBP groups (+7.1 percentile versus -4.2 percentile; p < 0.05). Shifting of the mechanical axis by two zones was noted medially in four TBP patients and laterally in two PETS patients. Conclusion More implant-related complications and revision surgeries for angular deformities were associated with TBP. A tendency of varus and valgus deformity after epiphysiodesis using TBP and PETS was observed, respectively. Patients and families should be informed of the risks and regular postoperative follow-up is recommended. Level of evidence Level III

Growth modulation of angular deformities with a novel constant force implant concept-preclinical results

Purpose Varus-valgus deformities in children and adolescents are often corrected by temporary hemi-epiphysiodesis, in which the physis is bridged by an implant to inhibit growth. With standard implant solutions, the acting forces cannot be regulated, rendering the correction difficult to control. Furthermore, the implant load steadily increases with ongoing growth potentially leading to implant-related failures. A novel implant concept was developed applying a controlled constant force to the physis, which carries the potential to avoid these complications. The study aim was to proof the concept in vivo by analyzing the effect of three distinct force levels on the creation of varus deformities. Methods The proposed implant is made of a conventional cerclage wire and features a twisted coil that unwinds with growth resulting in an implant-specific constant force level. The proximal medial tibial physes of 18 lambs were treated with the implant and assigned to three groups distinct by the force level of the implant (200 N, 120 N, 60 N). Results The treatment appeared safe without implant-related failures. Deformity creation was statistically different between the groups and yielded on average 10.6° (200 N), 4.8° (120 N) and 0.4° (60 N) over the treatment period. Modulation rates were 0.51°/mm (200 N), 0.23°/mm (120 N) and 0.05°/mm (60 N) and were constant throughout the treatment. Conclusion By means of the constant force concept, controlled growth modulation appeared feasible in this preclinical experiment. However, clinical trials are necessary to confirm whether the results are translatable to the human pathological situation.

Monomelic Maffucci syndrome

Maffucci syndrome is a rare congenital, non-hereditary condition characterised by presence of multiple enchondromas and haemangiomas. Enchondromatous lesions affecting epiphysial growth plates can lead to angular deformities and leg-length discrepancy in the lower limb. We describe a 12-year-old girl with monomelic Maffucci syndrome affecting her left lower limb. She presented with progressive genu valgus deformity of her left knee. This caused her to limp during her gait and was a cosmetic dissatisfaction. The deformity affected her quality of life. She underwent a supracondylar distal femoral corrective osteotomy with a successful clinical outcome and restoration of her gait and cosmetic deformity.

Comparison between Novice and Experienced Surgeons Performing Corrective Osteotomy with Patient-Specific Guides in Dogs Based on Resulting Position Accuracy

Corrective osteotomy has been applied to realign and stabilize the bones of dogs with lameness. However, corrective osteotomy for angular deformities requires substantial surgical experience for planning and performing accurate osteotomy. Three-dimensional printed patient-specific guides (3D-PSGs) were developed to overcome perioperative difficulties. In addition, novices can easily use these guides for performing accurate corrective osteotomy. We compared the postoperative results of corrective osteotomy accuracy when using 3D-PSGs in dogs between novice and experienced surgeons. We included eight dogs who underwent corrective osteotomy: three angular deformities of the radius and ulna, three distal femoral osteotomies, one center of rotational angle-based leveling osteotomy, and one corrective osteotomy with stifle arthrodesis. All processes, including 3D bone modeling, production of PSGs, and rehearsal surgery were carried out with computer-aided design software and a 3D-printed bone model. Pre- and postoperative positions following 3D reconstruction were evaluated by radiographs using the 2D/3D registration technique. All patients showed clinical improvement with satisfactory alignment and position. Postoperative accuracy evaluation revealed no significant difference between novice and experienced surgeons. PSGs are thought to be useful for novice surgeons to accurately perform corrective osteotomy in dogs without complications.

Clinical measurement of intermalleolar distance in Western Indian population

Background: Angular deformities around the knee are one of the common basis of presentation at orthopaedic clinic and intermalleolar distance (IMD) is an essential anthropometric tool for evaluation of the angular status of the lower limb.Methods: 500 healthy (330 male and 170 female) subjects between 20 to 40 years of age were taken for IMD measurement in standing and supine position by digital vernier caliper.Results: The normal range of IMD in western Indian population in between 32-58 mm. IMD in standing position was 42.47 mm with (95% CI = 40.51 to 44.42 mm) and in supine position was 34.45 mm with (95% CI = 32.78 to 36.13 mm). Mean IMD in male in standing position was 40.01 mm while in female it was 43.74 mm observed. Statically significant difference was observed in posture change and according to age.Conclusions: Significantly higher value in female, in standing position and in higher age group were observed.