Primary total knee replacement for tibial plateau fractures in older patients: a systematic review of 197 patients.

INTRODUCTION: Tibial plateau fractures are typically treated with osteosynthesis. In older patients, osteosynthesis is associated with some complications, risk of post-traumatic osteoarthritis and long partial, or non-weight bearing during the recovery phase. To avoid these problems, primary total knee replacement (TKR) has become an increasingly common treatment option. The aim of this study was to evaluate all the relevant literature and summarize the current evidence-based knowledge on the treatment of tibial plateau fractures with primary TKR in older patients. MATERIALS AND METHODS: A systematic literature search of studies on total knee replacement (TKR) as primary treatment for acute traumatic tibial plateau fracture was conducted using OVID Medline, Scopus, and Cochrane databases from 1946 to 18 November 2019. We included all studies without restrictions regarding total knee replacement (TKR) as primary treatment for acute traumatic tibial plateau fracture. RESULTS: Of the 640 reviewed articles, 16 studies with a total of 197 patients met the inclusion criteria. No controlled trials were available, and the overall quality of the literature was low. The results, using different clinical scoring systems, were good or fair. Four-year follow-up complication (6.1%) and revision (3.6%) rates after primary TKR appeared to be lower than after secondary TKR (complication rate 20-48%, revision rate 8-20%) but higher than after elective primary TKR. CONCLUSION: Based on low-quality evidence, TKR appears to be a useful treatment option for tibial plateau fractures in older patients. Controlled trials are mandatory to determine the relative superiority of these two options as primary treatment of tibial plateau fractures in older patients.

Lack of a central role for osteoprogenitor cells from the femoral canal in heterotopic ossification of the hip: an experimental study in a rat model.

We have developed an animal model to examine the formation of heterotopic ossification using standardised muscular damage and implantation of a beta-tricalcium phosphate block into a hip capsulotomy wound in Wistar rats. The aim was to investigate how cells originating from drilled femoral canals and damaged muscles influence the formation of heterotopic bone. The femoral canal was either drilled or left untouched and a tricalcium phosphate block, immersed either in saline or a rhBMP-2 solution, was implanted. These implants were removed at three and 21 days after the operation and examined histologically, histomorphometrically and immunohistochemically. Bone formation was seen in all implants in rhBMP-2-immersed, whereas in those immersed in saline the process was minimal, irrespective of drilling of the femoral canals. Bone mineralisation was somewhat greater in the absence of drilling with a mean mineralised volume to mean total volume of 18.2% (sd 4.5) versus 12.7% (sd 2.9, p < 0.019), respectively. Our findings suggest that osteoinductive signalling is an early event in the formation of ectopic bone. If applicable to man the results indicate that careful tissue handling is more important than the prevention of the dissemination of bone cells in order to avoid heterotopic ossification.

Bone formation zones in heterotopic ossifications: histologic findings and increased expression of bone morphogenetic protein 2 and transforming growth factors beta2 and beta3.

Heterotopic ossifications (HOs) formed after total endoprosthetic replacement of the hip joint were collected during revision surgery (n = 7). Tissues collected during regular hip arthroplasty (n = 12) were used as reference. Histomorphometric analysis was performed for assessment of bone formation activity in HOs and reference bone. HOs were dissected with histological guidance into three zones: formed bone, zone of active bone formation, and zone with fibrous connective and fibrocartilagineous tissue. Relative expression of the mRNA for bone morphogenetic protein 2 (BMP-2), transforming growth factor beta2 (TGF-beta2), and TGF-beta3 was determined by reverse-transcription polymerase chain reaction relative to beta-actin. Expression of all three growth factors was higher than in orthotopic bone. Similarly, the osteoid surface density was increased in HOs. The levels of all growth factors were higher in the zone of active bone formation or remodeling than in the zone of formed bone. In matured HOs, the osteoid surface density as well as mRNA levels were lower, although still significantly raised, indicating that bone formation slows down after 2 years. Immunohistochemical analysis demonstrated the presence of TGF-beta1, TGF-beta2, TGF-beta3, and BMP-2 proteins in the zone of bone formation. We conclude that bone formation after heterotopic bone induction is initially intense, slows down within 2 years, and thereupon continues as active remodeling mainly on the border of HO. Our data indicate that BMP-2, TGF-beta2, and TGF-beta3 are involved in bone formation in HO.

Inter-observer reliability in the assessment of heterotopic ossification: proposal of a combined classification.

We applied four published classifications for assessment of heterotopic ossification after total hip arthroplasty (Arcq, Brooker, DeLee and Della Valle [1, 2, 5, 6]. The average incidence of heterotopic ossification varied from 19.8% to 27.7%. The inter-observer reliability of the various classifications was determined by Cohen's Kappa statistic. Kappa values ranged from 0.897 for Arcq's to 0.814 for Brooker's classification. In order to increase the reliability and consistency, we propose a new classification system combining Brooker's and Della Valle's classifications. This new classification preserves the high reliability of Della Valle's system and is comparable to previous publications since it includes Brooker's criteria.

Heterotopic ossification after total hip arthroplasty.

We studied 178 patients undergoing total hip arthroplasty (66 men and 112 women) retrospectively, with regard to the incidence and severity of heterotopic ossification and the significance of postoperative prophylaxis with non-steroid anti-inflammatory drugs. The overall incidence of heterotopic ossification was 32% 1 year after surgery. The factors increasing the incidence were male gender, previous arthroplasty of the contralateral hip joint, previous surgery on the hip, absence of preoperative treatment with non-steroidal anti-inflammatory drugs and an operating time of more than 100 min. The incidence of heterotopic ossification was lower in the patients of O blood group.

[Post-traumatic repair of the tibia in rats]. / Posttravmaticheskiaia reparatsiia bolshebertsovo kosti u krys.

Posttraumatic bone repair was studied histologically in 88 adult male Wistar rats. Thick, semithin and thin sections were stained with standard methods and investigated (microanatomy, histology, EM). The experimental animals were divided into five main groups: 1) control; 2) trained (swimming); 3) immobilized; 4) formalized (0.2 mg/kg i.m. every day); 5) alcoholised (3% alcohol instead of drinking water). The first group was divided into animals wit periost, contacted with endost and bone marrow and animals without periost contacts (with isolated periosteum). Bone perforation causes local hemorrhage and tissue destruction. Thr first reparative changes on the first-seventh days (proliferating fibroblasts and capillary sprouts grow into the blood clot and injured area, degranulation of neutrophils and tissue basophils, appearance of activated macrophages and osteoclasts) occur in soft tissue. Intensive collagen synthesis in fibroblasts began. On the fourteenth day collagen synthesis in osteoblasts was increased (packed collagen fibrils in vacuolated cytoplasm). Posttraumatic osteohistogenesis on d 4-21 was generally completed on d 28-42 bone formation (morphogenesis) and permanent remodeling were continued. Periosteal osteogenesis and bone repair require an existence of the periosteum contact with endosteum and bone marrow (growth and differentiation of endosteal bone callus was inhibited and those of periosteal callus was arrested in groups with isolated periosteum). Similar results were achieved in i.p. heterotopic autografts of repaired tissue in diffusion chamber (with isolated periosteal osteogenetic cells appearing only by 21st day after bone injury). In trained rats bone repair was stimulated, while in immobilised and in injured animals it was inhibited and resulted in chronic inflammation of bone marrow and abscesses.

Bone healing models in rat tibia after different injuries.

AIMS: Gradual elaboration of an adequate and efficient multistage method for experimental remodelling of specific wound healing process--bone repair. Comparison of clinical characteristics with the results of microanatomy, histology, electronmicroscopy and computer morphometry. MATERIAL AND METHODS: An investigation of posttraumatic bone repair after internal fracture, excision and cortical perforation was carried out on 142 young adult male Wistar rats. The repair was studied in normal and affected animals (exercises, immobilization, isolation of periost) at 1-42 days after operation. RESULTS: The posttraumatic bone callus development and the related soft tissue repair, likewise the continuous remodelling, is an ordinary process of osteohisto- and organogenese. In trained rats the blood supply and bone formation is increased, whereas in immobilized animals it is inhibited and destroyed (osteoporose, pseudoarthrosis). After the injury some characteristics of bone repair histogenese will be became evident (after the perforation the primary endosteal and secondary periosteal ossification, inhibition of endosteal bone repair after the isolation of periost etc.). CONCLUSION: The posttraumatic bone healing, like embryohistogenese, has similar repair stages in all models of the experiments as well as similar tissue and cell responses (callus formation, its replacement, bone remodelling, etc.). However, the repair process in general (order of chondrous and/or bone callus stages, etc.) is variable and dependent on the mode and degree of injury. The use of bone cortex perforation in wound healing study is more recommendable as compared to internal fracture and excision (possibility of in situ study the periost and callus tissue compartments in bone repair machinery separately).