Comparison of femoral neck shortening after femoral neck system and cannulated cancellous screw fixation for displaced femoral neck fractures in young adults.

BACKGROUND: The purpose of this study was to compare the outcomes of femoral neck shortening between the femoral neck system (FNS) and the cannulated cancellous screws (CCS) for displaced femoral neck fractures in young adults PATIENTS AND METHODS: In this retrospective analysis, 225 patients aged 18-65 years with displaced femoral neck fracture were divided into two groups according to internal fixation: 135 patients in the FNS group and 90 patients in the CCS group. The length of hospital stay, duration of surgery, intraoperative blood loss, quality of reduction, extent of femoral neck shortening, incidence of femoral neck shortening, femoral neck shortening at each follow-up visit, Harris hip score (HHS), reoperation, and complications were compared between the two groups. RESULTS: The median follow-up time was 28.2 (26.0, 31.2) months in the FNS group and 30.2 (26.3, 34.7) months in the CCS group. The follow-up time, age, sex distribution, body mass index (BMI), mechanism of injury, injured side, length of hospital stay, time from injury to surgery, and fracture classification were similar between the groups. Duration of surgery was longer in the FNS group (65.0 (55.0, 87.0) min versus 55.0 (50.0, 65.0) min, P<0.001); intraoperative blood loss was greater in the FNS group (50.0 (20.0, 60.0) ml versus 20.0 (10.0, 35.0) ml, P<0.001). Femoral neck shortening was 2.4 (1.0, 4.5) mm in the FNS group versus 0.6 (0.0, 2.6) mm in the CCS group at 1 month postoperatively (P<0.001); 3.7 (1.8, 6.4) mm in the FNS group versus 1.2 (0.6, 3.8) mm in the CCS group at 3 months (P<0.001); 4.1(2.4, 7.7) mm in the FNS group versus 2.3 (1.1, 4.4) mm in the CCS group at 6 months (P<0.001); 4.2 (2.6, 7.7) mm in the FNS group versus 2.6 (1.3, 4.6) mm in the CCS group at 12 months (P<0.001); and 4.5 (2.8, 8.0) mm in the FNS group versus 2.8 (1.5, 4.8) mm in the CCS group at 18 months (P<0.001). The two groups showed no significant differences in HHS, reoperation, and reduction quality. CONCLUSION: Compared to CCS, FNS is deficient in preventing femoral neck shortening. Future research should focus on improving FNS in terms of preventing femoral neck shortening.

Intertrochanteric (Reverse Oblique) Fracture Subclassifications AO/OTA 31-A3 Have No Effect on Outcomes or Postoperative Complications.

Background: Reverse oblique intertrochanteric fractures (ROFs) are unstable extracapsular hip fractures that present a mechanical challenge. These fractures are classified as AO/Orthopaedic Trauma Association (OTA) 31-A3 according to the Trauma Association classification system and can further be subclassified into 3 subtypes based on their specific characteristics. The study aimed to evaluate and compare the radiographic and clinical outcomes of the 3 subtypes of ROFs. Methods: A retrospective study was conducted at a single high-volume, tertiary center, where data were collected from electronic medical records of consecutive patients who underwent surgical fixation of AO/OTA 31-A3 fractures. Patients with less than 1-year follow-up, pathological fractures, and revision surgery were excluded. The subtypes of fractures were classified as 31-A3.1 (simple oblique), 31-A3.2 (simple transverse), and 31-A3.3 (wedge or multi-fragmentary). The operation was done using 4 different fixation methods, and radiological evaluation was performed at routine intervals. Results: The final population consisted of 265 patients (60.8% women) with a mean age of 77.4 years (range, 50-100 years) and the mean follow-up time was 35 months (range, 12-116 months). The incidence of medical complications was similar across the groups. However, there was a trend toward a higher incidence of orthopedic complications and revision rates in the 31-A3.2 group, although this was not statistically significant (p = 0.21 and p = 0.14, respectively). Conclusions: Based on the findings of this study, no significant differences were observed between the groups, indicating that the subclassifications of AO/OTA 31-A3 fractures do not have a significant impact on surgical outcomes or the occurrence of postoperative complications.

[Diagnostics and classification of distal radius fractures]. / Diagnostik und Klassifikation der distalen Radiusfraktur.

Fractures of the distal radius show a wide spectrum of different fracture patterns. Although standard X­ray images are sufficient for extra-articular fractures, the exact analysis of intra-articular fractures requires the use of computed tomography (CT) with coronal, sagittal and axial sectional images. The classification is based on the Working Group for Osteosynthesis Questions (AO) criteria. The treatment strategy can be more precisely defined by a CT-based classification. Special attention must be paid to the presence of the key corners, as they have a high risk for primary or secondary dislocation if they not adequately stabilized.

[Basic principles of surgical treatment of distal radius fractures]. / Grundprinzipien der operativen Versorgung der distalen Radiusfraktur.

Distal radius fractures are one of the most frequent fractures of the upper extremities. The decision for conservative or surgical treatment is made after appropriate diagnostics using conventional radiographic and usually computed tomography imaging examinations. If the indications for surgical treatment are present, various options for reduction and fixation are available. The spectrum ranges from closed to open procedures up to accompanying arthroscopic support. Appropriate preoperative patient education about the procedure and the planned postinterventional treatment is essential. The goal of treatment is to restore wrist function while maintaining mobility and strength with a low risk of complications. All surgical procedures share the principle of reduction to restore anatomical relationship followed by fixation. Closed procedures include fixation with Kirschner wires and the construction of an external fixator. Volar locking plate osteosynthesis has become established in recent years as the method of choice for the majority of the fractures to be treated. For special fracture patterns and the treatment of accompanying injuries, arthroscopic support can be indicated. There is no uniform consensus on the best choice of procedure. This article discusses the possible procedures including the approaches, fixation techniques and specific follow-up treatment.

Sustentaculum fracture fixation with lateral plate or medial screw fixation are equivalent.

BACKGROUND: Fixation of sustentaculum tali fractures is important to maintain the biomechanical function of the subtalar joint. A common method of fixation is securing the sustentacular fragment by way of a laterally based locking plate (LP). A medial approach with a single screw (MS) has been proposed as an alternative method of fixation. METHODS: Five pairs of formalin-preserved cadaveric ankles with the subtalar joint and interosseous ligaments intact ("osseous cadavers") and four pairs of fresh-frozen cadaveric ankles with soft-tissue preserved dissected from mid-tibia down ("soft tissue cadavers") were used in the study. The left ankle was randomly assigned to one of the two fixation methods (LP or MS), while the right ankle was the opposite. These same steps for fixation were repeated for six synthetic ankle models. All models were loaded with a body mass of 80 kg. Statistical differences between LP and MS stiffness were determined using a paired t-test in cadavers and un-paired t-tests in synthetic ankles. RESULTS: For osseous cadaveric ankles, LP demonstrated a mean stiffness of 232.95(SD: 59.96) N/mm, while MS was 239.72(SD:131.09) N/mm (p = 0.9293). For soft tissue cadaveric ankles, LP mean stiffness was 133.58(SD:37.84) N/mm, while MS was 134.88(SD:20.75) N/mm (p = 0.9578). For synthetic ankles, LP mean stiffness was 220.40(SD:81.93) N/mm, while MS was 261.50(SD:100.21) N/mm (p = 0.6116). CONCLUSIONS: Across all three models, there was no significant difference between LP and MS methods. Retrospective observational studies are recommended to assess patient outcomes from each of the methods.

In-vitro external fixation pin-site model proof of concept: A novel approach to studying wound healing in transcutaneous implants.

External fixation is an essential surgical technique for treating trauma, limb lengthening and deformity correction, however infection is common, with infection rates ranging from 4.5 to 100% of cases. Throughout the literature researchers and clinicians have highlighted a relationship between excessive movement of the pin and skin and an increase in the patient's risk of infection, however, currently no studies have addressed this role of pin-movement on pin-site wounds. This preliminary study describes a novel in vitro pin-site model, developed using a full-thickness human skin equivalent (HSE) model in conjunction with a bespoke mechanical system which simulates pin-movement. The effect of pin-movement on the wound healing response of the skin equivalents was assessed by measuring the expression of pro-inflammatory cytokines. Six human skin equivalent models were divided into three test groups: no pin as the control, static pin-site wound and dynamic pin-site wound (n = 3). On day 3 concentrations of IL-1α and IL-8 showed a significant increase compared to the control when a static fixation pin was implanted into the skin equivalent (p < 0.05) and (p < 0.005) respectively. Levels of IL-1α and IL-8 increased further in the dynamic sample compared to the static sample (p < 0.05) and (p < 0.0005). This study demonstrates for the first time the application of HSE model to study external-fixation pin-movement in vitro. The results of this study demonstrated pin-movement has a negative effect on soft-tissue wound-healing, supporting the anecdotal evidence reported in the literature, however further analysis of wound heading would be required to verify this hypothesis.

Tibial Eminence Avulsion in a Tibial Plateau Fracture - Our Approach: A Clinical Case.

A middle-aged female patient with a tibial plateau fracture combined with an avulsion of the tibial eminence was treated with a combination of medial plate fixation for the plateau and an arthroscopic aided nonabsorbable suture of the eminence. Our technique for tibial eminence avulsion fractures has no interference with tibial plateau osteosynthesis materials and has proven, once again, to have good results in the treatment of combined and complex injuries of the knee.

Stability of Proximal Femoral Osteotomies in Pediatric Bone Models Fixed with Flexible Intramedullary Nails and Evaluated by the Finite Element Method.

Objective To evaluate the stability of osteotomies created in the subtrochanteric and trochanteric regions in a pediatric femur model fixed by flexible intramedullary rods. Method Tomographic sections were obtained from a pediatric femur model with two elastic titanium rods and converted to a three-dimensional model. This model created a mesh with tetrahedral elements according to the finite element method. Three virtual models were obtained, and osteotomies were performed in different regions: mediodiaphyseal, subtrochanteric, and trochanteric. A vertical load of 85N was applied to the top of the femoral head, obtaining the displacements, the maximum and minimum main stress, and the equivalent Von Mises stress on the implant. Results With the applied load, displacements were observed at the osteotomy site of 0.04 mm in the diaphyseal group, 0.5 mm in the subtrochanteric group, and 0.06 mm in the trochanteric group. The maximum stress in the diaphyseal, subtrochanteric, and trochanteric groups was 10.4 Pa, 7.52 Pa, and 26.4 Pa, respectively. That is around 40% higher in the trochanteric group in regards to the diaphyseal (control). The minimum stress of the bone was located in the inner cortical of the femur. The equivalent Von Mises stress on the implants occurred at osteotomy, with a maximum value of 27.6 Pa in the trochanteric group. Conclusion In both trochanteric and subtrochanteric osteotomies, fixation stability was often lower than in the diaphyseal model, suggesting that flexible intramedullary nails are not suitable implants for proximal femoral fixations.

Pre-sliding technique to improve femoral neck system against the shortening: a retrospective cohort study.

OBJECTIVE: To investigate the efficacy of using pre-sliding technique to prevent postoperative shortening of displaced femoral neck fracture fixed with femoral neck system (FNS). METHODS: Retrospective analysis of 110 cases of displaced femoral neck fracture treated with femoral neck system from September 2019 to November 2022 in our center, which were divided into 56 cases in the pre-sliding group and 54 cases in the traditional group. The baseline data such as gender, age, side, mechanism of injury, fracture type, operation time, intraoperative bleeding were recorded and compared between the two groups, and the quality of fracture reduction, shortening distance, Tip Apex Distance (TAD), union time, Harris score of the hip were also compared between the two groups. RESULTS: The TAD value of the pre-sliding group was smaller than that of the traditional group, and the difference was statistically significant (P < 0.001). The shortening distance in both groups on postoperative day 1 was smaller in the pre-sliding group than in the traditional group, but the difference was not statistically significant (P = 0.07), and the shortening distance was smaller than in the traditional group at 1, 3, 6, and 12 months postoperatively, and the difference was statistically significant (all P < 0.001). Of the 110 cases, 34 (30.9%) had moderate or severe shortening, of which 24 (44.4%) were in the traditional group and 10 (17.9%) in the pre-sliding group, and the difference was statistically significant (P < 0.001), and the Harris score at 1 year, which was higher in the pre-sliding group than in the traditional group, and the difference between the two groups was statistically significant (P < 0.001). There was no statistically significant difference in the comparison of baseline data such as gender, age, side, mechanism of injury, fracture type, operation time, intraoperative bleeding, and quality of reduction between the two groups (all P > 0.05), and no statistically significant difference in fracture healing time between the two groups (P = 0.113). CONCLUSION: The use of the pre-sliding technique of displaced femoral neck fracture fixed with FNS reduces the incidence of moderate and severe shortening, improves the postoperative TAD value, and improves the hip function scores, with a satisfactory midterm efficacy.

Use of metatarsal hook plates in the treatment of multifragmentary patellar fractures - A case series.

The surgical management of patellar fractures typically yielded satisfactory results; however, in situations involving multifragmented patellar fractures or those affecting the inferior pole, it became imperative to employ alternative osteosynthesis techniques that enhanced stability, enabled early rehabilitation initiation, prevented implant failure, and avoided reduction loss before fracture consolidation. In this context, an unconventional osteosynthesis alternative was presented, utilizing an anatomically designed hook plate originally intended for the fifth metatarsal. This technique was successfully applied in three patients with multifragmentary patellar fractures, allowing stable fixation of small or marginal fragments through the plate's hooks without compromising vascularity. Fracture consolidation was achieved without reduction loss, and owing to its low profile, patient discomfort and irritation were minimized compared to traditional tension band or wiring techniques. This approach suggested the potential to forego early plate removal, thereby contributing to a more effective management of patellar fractures. Level of evidence: IV.

Is reduction necessary in overriding metaphyseal distal radius fractures in children under 11 years: a systematic review and meta-analysis of comparative studies.

OBJECTIVE: To determine the necessity of reduction in the treatment of overriding metaphyseal distal radius fractures (DRF) in children under 11 years. METHODS: In this systematic review and meta-analysis, PubMed, Embase, and Cochrane databases were searched to retrieve studies published from inception to 2023. Two reviewers independently screened for studies with observational or randomized control design comparing two treatments for overriding metaphyseal DRF in patients under 11 years: simple casting without reduction (SC group) versus closed reduction plus casting or pin fixation (CRC/F group); with varying outcomes reported (CRD471761). The risk of bias was assessed using the ROBINS-I tool. RESULTS: Out of 3,024 screened studies, three met the inclusion criteria, 180 children (mean age 7.1 ± 0.9 years) with overriding metaphyseal DRF: SC-group (n = 79) versus CRC/F-group (n = 101). Both treatment groups achieved 100% fracture consolidation without requiring further manipulation. The SC-group showed significantly fewer complications (mean difference [MD] 0.08; 95% CI [0.01, 0.53]; I2 = 22%; P < 0.009) and trends towards better sagittal alignment (MD 5.11; 95% CI [11.92, 1.71]; I2 = 94%; P < 0.14), less reinterventions (MD 0.31; 95% CI [0.01, 8.31]; P < 0.48), and fewer patients with motion limitation at the end of follow-up (MD 0.23; 95% CI [0.03,  1.98]; P < 0.18), although these findings were not statistically significant. CONCLUSIONS: Despite a limited number of studies comparing SC versus CRC/F in overriding DRF in children under 11 years, this study suggests that anatomical reduction is not necessary. Treating these fractures with SC, even when presenting with an overriding position, leads to reduced complications, shows a trend towards fewer reinterventions, improved sagittal alignment, and less limitation in patient motion. LEVEL OF EVIDENCE: Level III, Systematic review of Level-III studies.

Definitive internal fracture fixation followed by staged free flap coverage ("fix followed by flap" protocol) for open Gustilo type IIIB fractures.

BACKGROUND: Although the concept of the "fix and flap" approach, in which definitive fracture fixation and flap coverage are completed in a single procedure at the earliest opportunity may seem ideal for the treatment of Gustilo type IIIB open fractures, the individual circumstances of patients, such as polytrauma or multiple fracture cases may not allow for the immediate fracture fixation and flap coverage ("fix and flap" approach). In our hospital, patients with Gustilo type IIIB open fractures are treated with definitive internal fixation of the fracture followed by staged flap coverage ("fix followed by flap" protocol) when the "fix and flap" approach was not feasible due to the patient's condition or difficulty in coordinating surgery schedules. The "fix followed by flap" protocol provides benefits in terms of flexibility in adjusting the surgical timetable, simplifying the planning of flap coverage following fracture fixation, and minimizing individual surgical invasion. METHODS: We reviewed 10 cases of severe open fractures treated with the "fix followed by flap" protocol and evaluated their outcomes. All surgical procedures, including wound debridement, fracture fixation, and flap coverage, were performed by orthoplastic surgeons specializing in both fracture surgery and microsurgery including soft tissue reconstruction. RESULTS: All free flaps survived, and no partial necrosis was observed. None of the patients developed postoperative deep infection up to the last follow-up. Fracture union was achieved in all patients with or without autologous bone grafts. The median time for union was 9.4 months (range, 4-12 months). CONCLUSIONS: This study presents favorable outcomes of treatment for Gustilo type IIIB open fractures with fracture fixation followed by staged flap coverage ("fix followed by flap" protocol). Despite a delay in flap coverage, the consistency of treatment provided by orthoplastic surgeons may have contributed to the favorable outcomes in this study.

Treatment options and outcomes for delayed scapular anatomical neck fractures: a case report and review of the literature.

INTRODUCTION: Scapular anatomical neck fractures are among the most infrequent shoulder girdle fractures. Only seven radiologically confirmed cases of scapular anatomical neck fractures have been documented in the literature to date, of which only one case underwent delayed surgery. CASE PRESENTATION: A 34-year-old male Persian patient with morbid obesity was diagnosed with a scapula anatomical neck fracture after a motor vehicle collision. The radiographic assessment of the patient indicated an increase in the scapular glenopolar angle (73.9°). Due to concurrent chest and head injuries, surgical intervention was deferred until 6 weeks following the injury. The posterolateral limited Dupont-Evrard approach was used because of the patient's extremely high body mass index. Two plates were utilized to achieve stable fixation of the glenoid neck fracture. Following a 1 year follow-up period, complete fracture union was successfully attained, resulting in a constant score of 79. CONCLUSIONS: The most accurate radiographic indicators of these fractures are a superior fracture line located laterally to the coracoid process, a small inferior spike, and an elevated glenopolar angle. The only tendon attached to the glenoid is the long head of the triceps, making these fractures unstable; therefore, surgery is required in the majority of instances. The small size of the fractured component makes stabilization more difficult. Overall, anatomical scapular neck fractures are extremely uncommon and distinguished from other scapular fractures by their unique radiological and biomechanical characteristics. This case highlights the challenges encountered when managing scapular fractures in patients with morbid obesity. The delayed surgical intervention and the choice of surgical approach tailored to the patient's specific anatomical and physiological considerations proved to be effective in achieving a favorable outcome.

Associations with Discharge to Post-Acute Care Facilities Among Patients Undergoing Open Reduction Internal Fixation of Distal Radius Fractures.

Introduction: Distal radius fractures are a common injury of the hand and wrist that often require intensive rehabilitation. We sought to identify risk factors associated with discharge to a post-acute care facility following distal radius fracture repair. Methods: The 2011 to 2016 National Surgical Quality Improvement Program® (NSQIP) database was queried for all Current Procedural Terminology (CPT) codes that corresponded with open distal radius fracture repair. Patients with concomitant traumatic injuries were excluded. Patient demographics, comorbidities, perioperative factors, laboratory data, and surgical details were collected. Our primary outcome was to determine postoperative discharge destination: home versus a post-acute care facility, and to identify factors that predict discharge to post-acute care facility. Secondary outcomes included unplanned readmission, reoperation, and complications. Results: Between 2011 and 2016, a total of 12,001 patients underwent open distal radius fracture repair and had complete information for their discharge. Of these analyzed patients, 3.24% (n = 389) were discharged to rehabilitation facilities. The following factors were identified on multivariate analysis to have an association with discharge to a post-acute care facility: 65 years or older, White race, underweight, using steroids preoperatively, American Society of Anesthesiologists (ASA) classification > 2, admitted from a nursing home or already hospitalized, anemic, undergoing bilateral surgery, wound classification other than clean, and complications prior to discharge. Conclusion: Factors identified by our study to have associations with discharge to post-acute care facilities following distal radius fracture repair can help in appropriate patient counseling and triage from the hospital to home versus a post-acute care facility.

Introduction: Les fractures du radius distal sont des blessures courantes de la main et du poignet qui exigent souvent une réadaptation intensive. Les chercheurs ont voulu déterminer les facteurs de risque associés au congé dans un établissement de soins post-aigus après la réparation d'une fracture du radius distal. Méthodologie: Les chercheurs ont fouillé la base de données 2011-2016 des NSQIP pour extraire tous les codes CPT (terminologie procédurale actuelle) qui correspondaient aux réparations des fractures ouvertes du radius distal. Les patients atteints d'autres blessures traumatiques ont été exclus. Les chercheurs ont colligé les caractéristiques démographiques des patients, leurs maladies sous-jacentes, les facteurs périopératoires, les données de laboratoire et l'information chirurgicale. Le résultat primaire consistait à déterminer la destination du congé postopératoire, soit le domicile ou l'établissement de soins postaigus, et à établir quels facteurs permettent de prédire un congé dans un établissement de soins postaigus. Les résultats secondaires incluaient des réadmissions non planifiées, la reprise de l'opération et les complications. Résultats: Entre 2011 et 2016, un total de 12 001 patients ont subi la réparation d'une fracture ouverte du radius distal et reçu de l'information complète lors de leur congé. De ce nombre, 3,24% (n = 389) ont obtenu leur congé dans des établissements de réadaptation. L'analyse multivariée a établi que les facteurs suivants étaient associés à un congé dans un établissement de soins postaigus : un âge de 65 ans ou plus, la race blanche, l'insuffisance pondérale, la prise de stéroïdes après l'opération, une classification d'ASA supérieure à 2, l'admission à partir d'un centre de soins de longue durée ou le fait d'être déjà hospitalisé, l'anémie, la chirurgie bilatérale, une classification des plaies autres que propre et des complications avant le congé. Conclusion: La présente étude a déterminé que certains facteurs associés au congé dans un établissement de soins postaigus après une réparation du radius distal peuvent contribuer à des conseils appropriés aux patients et à un triage de l'hôpital vers le domicile plutôt que vers un autre établissement.

Biomechanical comparison of composite and cadaveric humeri models in experiments on operated humeral shaft fractures.

A study was undertaken to determine how well contacting fracture fragments of composite bone replicated the behavior of fracture fragments in real bone. Ten composite and ten real humeral diaphyses were transected and reconstructed with limited-contact dynamic-compression plates. Two screws were placed on each side of the transection site and a calibrated electronic sensor sheet was placed between the imitated fracture fragments. After insertion of the distal screws, pressure measurements were made during insertion of the first proximal screw in compression mode, during insertion of the second screw in compression mode after loosening the first screw, and finally after retightening the first screw. The process was repeated after bending the plate. The contact area, the net compression force and the average compressive stress were computed and statistically compared. The composite bone and cadaveric bone differed in contact area and compressive stress but not in net compressive force. Plate bending did not produce a significant difference between composite and cadaveric bone. The results indicate that composite bone does not reproduce all the local fracture fragment conditions so that hardware testing in composite bone should proceed carefully. A gap between fracture fragments as is often used in comminuted fracture tests may remain as the most appropriate situation for fracture hardware testing.

Triceps Tendon Reattachment Using Mini Plates and Screws After Failure of Olecranon Avulsion Fracture Fixation in Osteoporotic Bone: A Case Report.

This is a case report of an 85-year-old woman with osteopenia who underwent olecranon avulsion fracture repair with supplemental triceps tendon repair following a fall on an outstretched arm. The initial procedure failed due to osteoporotic bone quality and an atraumatic disruption of the olecranon fracture fixation. The patient subsequently underwent further surgical intervention with an olecranon avulsion fracture excision and a novel triceps tendon repair technique using plate augmentation and fiber tape. Surgeons may consider this novel approach as an initial treatment for elderly patients with osteopenia or osteoporosis undergoing olecranon avulsion fracture fixation, to prevent the failure and consequent revision surgery.

Systemically administered zoledronic acid activates locally implanted synthetic hydroxyapatite particles enhancing peri-implant bone formation: A regenerative medicine approach to improve fracture fixation.

Fracture fixation in an ageing population is challenging and fixation failure increases mortality and societal costs. We report a novel fracture fixation treatment by applying a hydroxyapatite (HA) based biomaterial at the bone-implant interface and biologically activating the biomaterial by systemic administration of a bisphosphonate (zoledronic acid, ZA). We first used an animal model of implant integration and applied a calcium sulphate (CaS)/HA biomaterial around a metallic screw in the tibia of osteoporotic rats. Using systemic ZA administration at 2-weeks post-surgery, we demonstrated that the implant surrounded by HA particles showed significantly higher peri­implant bone formation compared to the unaugmented implants at 6-weeks. We then evaluated the optimal timing (day 1, 3, 7 and 14) of ZA administration to achieve a robust effect on peri­implant bone formation. Using fluorescent ZA, we demonstrated that the uptake of ZA in the CaS/HA material was the highest at 3- and 7-days post-implantation and the uptake kinetics had a profound effect on the eventual peri­implant bone formation. We furthered our concept in a feasibility study on trochanteric fracture patients randomized to either CaS/HA augmentation or no augmentation followed by systemic ZA treatment. Radiographically, the CaS/HA group showed signs of increased peri­implant bone formation compared with the controls. Finally, apart from HA, we demonstrated that the concept of biologically activating a ceramic material by ZA could also be applied to ß-tricalcium phosphate. This novel approach for fracture treatment that enhances immediate and long-term fracture fixation in osteoporotic bone could potentially reduce reoperations, morbidity and mortality. STATEMENT OF SIGNIFICANCE: • Fracture fixation in an ageing population is challenging. Biomaterial-based augmentation of fracture fixation devices has been attempted but lack of satisfactory biological response limits their widespread use. • We report the biological activation of locally implanted microparticulate hydroxyapatite (HA) particles placed around an implant by systemic administration of the bisphosphonate zoledronic acid (ZA). The biological activation of HA by ZA enhances peri­implant bone formation. •Timing of ZA administration after HA implantation is critical for optimal ZA uptake and consequently determines the extent of peri­implant bone formation. • We translate the developed concept from small animal models of implant integration to a proof-of-concept clinical study on osteoporotic trochanteric fracture patients. • ZA based biological activation can also be applied to other calcium phosphate biomaterials.

Primary stability in locking plate fixation for proximal humeral fractures may be increased by using an additional nail osteosynthesis in combination with locking plate osteosynthesis-A biomechanical comparison.

BACKGROUND: Stability is regarded as an important factor for proper healing and avoiding secondary dislocation in osteoporotic fractures of the proximal humerus. Several surgical techniques have been proposed for treatment, including intramedullary nail osteosynthesis and locking plate fixation. This study introduces a novel approach that combines both techniques and compares its primary stability with conventional methods. METHODS: The study involved 25 osteoporotic humeri with two-part fracture models, which were randomly assigned to locking-plate fixation, intramedullary nailing, or a combination of both techniques. The specimens were subjected to sinusoidal loading at 250 N in 20° abduction for 5000 cycles and then to quasi-static loading until failure. Fracture movement, failure mode, and failure load were measured and compared among the groups. FINDINGS: The groups fixated with intramedullary nailing and the groups fixated with intramedullary nailing and locking plate fixation showed significantly lower fracture motion than the group using locking plate fixation only (p < 0.005) and significantly higher load to failure (p = 0.007 and p = 0.0062, respectively). There was no significant difference between the group using intramedullary nailing and the group using locking-plate fixation and intramedullary nailing in fracture movement or load-to-failure (p > 0.005). INTERPRETATION: The results indicate that locking plate fixation provides less primary stability than intramedullary nailing or the combined of both techniques. This combined approach may offer advantages as a treatment for complex proximal humeral fractures in osteoporotic bone, and specific implants should be developed to ensure optimal treatment.

BoneTape: A novel osteosynthetic device for the stabilization of zygomatic fractures.

BACKGROUND: The study aims to assess the safety and effectiveness of BoneTape™, a new resorbable bone fixation device, using a zygomatic fracture model in rabbits. METHODS: The study followed BoneTape™ samples and control (sham) groups over 2-, 6-, and 12-week periods post-zygomaticomaxillary (ZM) osteotomy and zygomaticofrontal (ZF) disarticulation. The osteotomized segments were analyzed for bone healing, inflammatory response, and tissue healing. µCT imaging and histological analysis were used to examine the axial alignment, offset, and quality of new bone formation. RESULTS: BoneTape™ samples demonstrated enhanced maintenance of the initial intraoperative positioning, reduced axial offset, and better alignment when compared with the control group, enabling stable bone healing under physiological loading conditions. Complete union was observed at 12-weeks in both groups. The BoneTape™ group experienced minimal immune and tissue reactions, classically associated with wound healing, and showed an increased number of giant cells at 6 and 12-weeks. CONCLUSION: BoneTape™ represents a promising advancement in osteosynthesis, demonstrating efficacy in maintaining stable zygomatic reconstruction and eliciting minimal immune response in a rabbit model. This study introduces BoneTape™ as a disruptive solution specifically designed for clinical application in cranio-maxillofacial fracture fixation, with the potential to eliminate the use of over-engineered solutions while offering benefits such as ease of application and fewer biologically disruptive steps.

Optimizing periprosthetic fracture management and in-hospital outcome: insights from the PIPPAS multicentric study of 1387 cases in Spain.

BACKGROUND: The incidence of all periprosthetic fractures (PPF), which require complex surgical treatment associated with high morbidity and mortality, is predicted to increase. The evolving surgical management has created a knowledge gap regarding its impact on immediate outcomes. This study aimed to describe current management strategies for PPF and their repercussions for in-hospital outcomes as well as to evaluate their implications for the community. METHODS: PIPPAS (Peri-Implant PeriProsthetic Survival Analysis) was a prospective multicentre observational study of 1387 PPF performed during 2021. Descriptive statistics summarized the epidemiology, fracture characteristics, management, and immediate outcomes. A mixed-effects logistic regression model was employed to evaluate potential predictors of in-hospital mortality, complications, discharge status, and weight-bearing restrictions. RESULTS: The study encompassed 32 (2.3%) shoulder, 4 (0.3%) elbow, 751 (54.1%) hip, 590 (42.5%) knee, and 10 (0.7%) ankle PPF. Patients were older (median 84 years, IQR 77-89), frail [median clinical frailty scale (CFS) 5, IQR 3-6], presented at least one comorbidity [median Charlson comorbidity index (CCI) 5, IQR 4-7], were community dwelling (81.8%), and had outdoor ambulation ability (65.6%). Femoral knee PPF were most frequently associated with uncemented femoral components, while femoral hip PPF occurred equally in cemented and uncemented stems. Patients were managed surgically (82%), with co-management (73.9%), through open approaches (85.9%) after almost 4 days (IQR, 51.9-153.6 h), with prosthesis revision performed in 33.8% of femoral hip PPF and 6.5% of femoral knee PPF. For half of the patients, the discharge instructions mandated weight-bearing restrictions. In-hospital mortality rates were 5.2% for all PPF and 6.2% for femoral hip PPF. Frailty, age > 84 years, mild cognitive impairment, CFS > 3, CCI > 3, and non-geriatric involvement were candidate predictors for in-hospital mortality, medical complications, and discharge to a nursing care facility. Management involving revision arthroplasty by experienced surgeons favoured full weight-bearing, while an open surgical approach favoured weight-bearing restrictions. CONCLUSIONS: Current arthroplasty fixation check and revision rates deviate from established guidelines, yet full weight-bearing is favoured. A surgical delay of over 100 h and a lack of geriatric co-management were related to in-hospital mortality and medical complications. This study recommends judicious hypoaggressive approaches. Addressing complications and individualizing the surgical strategy can lead to enhanced functional outcomes, alleviating the economic and social burdens upon hospital discharge. Level of Evidence Level IV case series. TRIAL REGISTRATION: registered at ClinicalTrials.gov (NCT04663893), protocol ID: PI 20-2041.