Periprosthetic fractures are becoming increasingly frequent due to aging population and growing number of total joint replacements involving joints different from hip and knee, such as shoulder and elbow. The treatment of these fractures still represents one of the major challenges for the orthopedic surgeon. Despite all efforts to understand and treat these patients, high rate of failure and mortality are still reported. In this review, the epidemiology of periprosthetic fractures, risk factors and results of surgical treatment are disclosed. Moreover, we propose a treatment algorithm based on the findings of the New Unified Classification System.

Diaphyseal fractures represent a complex biological entity that could often end into impaired bone-healing, with delayed union and non-union occurring up to 10% of cases. The role of the modern orthopaedic surgeon is to optimize the fracture healing environment, recognize and eliminate possible interfering factors, and choose the best suited surgical fixation technique. The impaired reparative process after surgical intervention can be modulated with different surgical techniques, such as dynamization or exchange nailing after failed intramedullary nailing. Moreover, the mechanical stability of a nail can be improved through augmentation plating, bone grafting or external fixation techniques with satisfactory results. According to the "diamond concept", local therapies, such as osteoconductive scaffolds, bone growth factors, and osteogenic cells can be successfully applied in "polytherapy" for the enhancement of delayed union and non-union of long bones diaphyseal fractures. Moreover, systemic anti-osteoporosis anabolic drugs, such as teriparatide, have been proposed as off-label treatment for bone healing enhancement both in fresh complex shaft fractures and impaired unions, especially for fragility fractures. The article aims to review the biological and mechanical principles of failed reparative osteogenesis of diaphyseal fractures after surgical treatment. Moreover, the evidence about the modern non-surgical and pharmacological options for bone healing enhancement will discussed.

Background: The classification systems for proximal humeral fractures routinely used in clinical practice include the Neer and Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) 2007 systems. Currently used systems have low inter- and intraobserver reliability. In 2018, AO/OTA introduced a new classification system with the aim of simplifying the coding process, in which the Neer four-part classification was integrated into the fracture description. The aim of the present work is to assess the inter- and intraobserver agreement of the new AO/OTA 2018 compared with the Neer and AO/OTA 2007 classifications. Materials and methods: A total of 116 radiographs of consecutive patients with proximal humeral fracture were selected and classified by three observers with different levels of experience. All three observers independently reviewed and classified the images according to the Neer, AO/OTA 2007, and new AO/OTA 2018 systems. To determine the intraobserver agreement, the observers reviewed the same set of radiographs after an interval of 8 weeks. The inter- and intraobserver agreement were determined through Cohen’s kappa coefficient analysis. Results: The new AO/OTA 2018 classification showed substantial mean inter- (k = 0.67) and intraobserver (k = 0.75) agreement. These results are similar to the reliability observed for the Neer classification (interobserver, k = 0.67; intraobserver, k = 0.85) but better than those found for the AO/OTA 2007 system, which showed only moderate inter- (k = 0.57) and intraobserver (k = 0.58) agreement. The two more experienced observers showed better overall agreement, but no statistically significant difference was found. No differences were found between surgical experience and agreement regarding specific fracture types or groups. Conclusions: The results showed that the Neer system still represents the more reliable and reproducible classification. However, the new AO/OTA 2018 classification improved the agreement among observers compared with the AO/OTA 2007 system, while still maintaining substantial descriptive power and simplifying the coding process. The universal modifiers and qualifications, despite their possible complexity, allowed a more comprehensive fracture definition without negatively affecting the reliability or reproducibility of the classification system. Level of evidence: Level III, diagnostic studies

In young patients with osteonecrosis of the femoral head (ONFH), short-stem total hip arthroplasty (THA) could allow a potential advantage in preserving metaphyseal bone-stock, when revision surgery might become necessary. However, only a few studies have evaluated the outcome of short-stem THAs in ONFH. We reviewed the prospectively collected data of a cementless partial neck-retaining short-stem with ceramic-on-ceramic bearings in ONFH patients. Thirty patients (37 hips) younger than 60 years (mean age at surgery, 51.5 years) underwent THA with the NANOS® stem (Smith and Nephew, Marl, Germany) from January 2006 to December 2012. All patients received a 32-mm or 36 mm ceramic femoral head. Harris hip score, WOMAC and UCLA activity score were recorded. Postoperative radiographs were evaluated for bone-implant fixation and osteolysis. Further analysis correlated clinical findings with implants characteristics and patient demographics at mean 5.6 years’ follow-up (range, 3–10 years). The clinical and functional results improved significantly (p < 0.001). At latest follow-up, mean HHS, WOMAC, and UCLA activity scores were 90 (range, 71–100), 94 (range, 76–100), and 6.3 (range, 4–10) points, respectively. The diameter of the femoral head did not influence the clinical outcome (p = 0.661). All hips showed bone ingrowth fixation of the acetabular and femoral components. No patients showed osteolysis. No revision for any reason was performed during the study period. The excellent clinical results and fixation pattern at mean 5.6 years’ follow-up reveal this implant as a reliable option in advanced stage of ONFH either. Further investigations are crucial to determine the long-term durability and to assess whether the association of ceramic-on-ceramic bearings, can be useful to achieve longer survivorship and lower complications rates. Registry number: ISRCTN 91336248 ; date of registration: 04/07/2017.

This study aims to explore if the arthroscopically assisted reduction and internal fixation (ARIF) technique is superior to the traditional open reduction and internal fixation (ORIF) technique in the treatment of tibial lateral plateau fractures. Forty patients with tibial plateau fractures (Schatzker type I–III) treated with ARIF or ORIF from 2012 to 2017 were included in this retrospective study. All patients received pre-operative radiographs and CT scans. The patients were divided into two groups (ARIF or ORIF). All patients had a minimum follow-up of 12 months and an average follow-up of 44.4 months. The clinical and radiographic outcomes were evaluated according to the Knee Society Score (KSS) and the modified Rasmussen radiological score. Satisfactory clinical and radiological results were found in 39 out of 40 (97.5%) patients. KSS and modified Rasmussen radiological score were significantly better in ARIF group. The mean KSS was 92.37 (± 6.3) for the ARIF group and 86.29 (± 11.54) for the ORIF group (p < 0.05). The mean modified Rasmussen radiographic score was 8.42 (± 2.24) for the ARIF group and 7.33 (± 1.83) for the ORIF group (p = 0.104). Worst clinical and radiological results were related to concomitant intra-articular lesions (p < 0.05). Meniscal tears were found and treated in 17 out of 40 (42.5%) patients. The overall complication rate was 10%. Both ARIF and ORIF provided a satisfactory outcome for the treatment of Schatzker I–III tibial plateau fractures. However, ARIF led to better clinical results than ORIF. No statistically significant differences were found in perioperative complications, radiological results, and post-traumatic knee osteoarthritis. Level III