Osteosynthesis Material Research Articles

The Use of 3D Model Printing for Acute Planning in Oral and Maxillofacial Traumatology

Introduction Due to the complex anatomy of craniomaxillofacial structures, facial reconstruction following high-impact traumas is extremely challenging. Therefore, this study aimed to evaluate the use of biomodels in the surgical planning of complex fractures and the sequelae in the oromaxillofacial region. Materials and Methods This is a cross-sectional, exploratory, descriptive, and quantitative documentary study. It was conducted at the “Dom Luiz Gonzaga Fernandes” Emergency and Trauma Hospital, in the hinterland of the state of Paraíba, in Brazil, based on cases recorded between November 2021 and November 2022. The research instrument utilized was a self-developed questionnaire. Results No statistically significant correlation was observed between the biomodel acquisition time and the length of hospitalization, with a Spearman's correlation coefficient of r = -0.079. Although the need for adjustment of osteosynthesis material was 50% in cases where acrylonitrile butadiene styrene (ABS) models were used, with p (1) = 0.464, in order to be significantly more faithful, it would require a study with a higher sample size. The average length of surgery, in minutes, was 91.25 ± 28.00. The average cost of the materials used to manufacture the biomodels, in Brazilian reais (R$), was R$122.00 ± R$89.09. Conclusion The use of biomodels in the surgical planning of complex fractures and oromaxillofacial sequelae did not increase the length of hospitalization. The material used for the prototype manufacture suggests a potential influence on its faithfulness. The length of surgery was shorter in interventions that utilized biomodels in the planning phase. It was also noted that the average cost of manufacture varies according to the type of material chosen and the quantity required.

Epidemiology of complications after non-compulsory planned hardware-removal after limbs fracture

IntroductionRemoval of hardware (HR) following a fracture is a frequent question from patients. The incidence of this kind of intervention remains very variable depending on the healthcare systems and its interest is debated in view of the benefits and associated risks that remain poorly defined. Mandatory preoperative information cannot be given optimally in this context. ObjectiveTo determine the rate of complications (major and minor) after non-compulsory planned hardware-removal following a limb fracture. HypothesisThe rate of major complications was greater than 1%. MethodsA 10-year retrospective single-center study included 1990 patients who had undergone routine HR. Analysis of medical records, with a minimum of one year of follow-up, allowed us to collect: patient data, the type and anatomical location of the osteosynthesis material, as well as the occurrence of a postoperative complication, categorized as a major complication (resulting in either a new surgical procedure, re-hospitalization, or lasting functional impairment) or a minor complication. ResultsOverall, 4.1% (79/1990) of patients experienced postoperative complications, including 1.56% (31/1990) major complications and 21 surgical revisions (1.06%). The time to onset of complications was 9.1 +/- 8.4 days. The most common complications were deep infections and impaired skin healing with superficial infection (55/79, 69.6%). Locations "around the knee" and "around the ankle" were at higher risk of complications (p < 0.01). Smoking was identified as a significant risk factor for complications, particularly deep infection (p = 0.004, OR = 8.7 [1.98; 38.11]). DiscussionNon-mandatory routine RH has a significant complication rate even in a healthy population. Preoperative information of the patient and the assessment of the benefit/risk balance are essential in this indication. This study also raises the question of mandatory smoking cessation preoperatively. Level of evidenceIV; retrospective study.

FIJACIÓN DE LAS FRACTURAS DE CUELLO FEMORAL DEL ADULTO: COMPARACIÓN RETROSPECTIVA ENTRE TORNILLOS CANULADOS Y EL SISTEMA DE CUELLO FEMORAL (FNS)

The FNS System DePuy Synthes® (EEUU, 2018) represents a recent alternative treatment for the fixation of femoral neck fractures, providing biomechanical advantages with respect to cannulated screws (3CS). The objective of this study is to compare the clinical results of both fixation methods. A retrospective collection of the 36 subcapital fractures treated with the FNS system was carried out compared with a retrospective search of the last 35 patients treated with 3CS. Age, sex, fracture pattern, delay until the intervention, lenght of intervention, hospital length stay, and haemoglobin loss were analyzed. In addition, the rate of avascular necrosis, nonunion, symptomatic femoral neck shortening, and material protrusion with or without its removal were recorded during a minimum follow-up of 6 months. No significant differences were found in age (p-value 0.32), fracture patterns (p-value 0.77), surgical delay (p-value 0.28), surgical time (p-value 0.226), length of hospital stay (p-value 0.921) and blood loss (p-value 0.086) between the two groups. A significantly higher overall complication rate was observed in the group treated with cannulated screws (p-value 0.004). Analysed separately, a higher rate of avascular necrosis, symptomatic shortening of the femoral neck, protrusion of the osteosynthesis material with or without removal was observed in the group treated with cannulated screws. The FNS system represents a safe and reproductible alternative for the fixation of femoral neck fractures, showing non-inferior outcomes to treatment with cannulated screws.

Aesthetic Approaches to Zygomatic Fracture Management: Achieving Optimal Outcomes With Minimal Scarring.

The zygomaticomaxillary complex is integral to facial aesthetics and is frequently involved in facial fractures. These injuries often necessitate surgical intervention, with open reduction and internal fixation being the standard treatment. This article presents a novel philosophy for managing zygomatic fractures, emphasizing the "Scarless Surgery" technique. The authors' approach prioritizes minimal osteosynthesis material and fixation points while utilizing the least visible surgical access. For isolated zygomatic arch fractures, an intraoral technique is preferred, whereas the frontozygomatic suture is approached through an upper eyelid crease for optimal aesthetic outcomes. The zygomaticomaxillary buttress is accessed through a vestibular mucosal incision and the infraorbital rim benefits from a transconjunctival approach. The findings suggest that fewer fixation points can still yield satisfactory stability and cosmetic results, aligning with literature supporting the efficacy of 1 and 2-point fixations. This modern technique not only minimizes visible scarring but also conforms to the contemporary push for minimally invasive surgical methods. The authors' experience and the existing literature support the efficacy of this approach, reinforcing its viability as a standard practice in the surgical management of facial trauma.

Focused High-Energy Extracorporeal Shock Wave Therapy (ESWT) for Bone healing Disorders of the Forearm and the Hand

ESWT is a non-surgical treatment option but can also be used in addition to surgical treatment (stabilisation, freshening, defect filling, removal of discomforting osteosynthesis material) for the treatment of delayed bone healing (DBH) and non-union (NU). Its value as well as influencing factors on the upper extremity have not been adequately quantified so far. Sixty cases were retrospectively studied after application of focused high-energy ESWT with regard to healing rate and consolidation time. The influence of age, location, time of treatment and treatment prior to and concurrent with ESWT were analysed. In 70% of the cases, healing occurred after a median of 2.4 months (DBH) and 2.8 months (NU). The median age of healed (DBH 44 y., non-union 35 y.) and non-healed (DBH 51 y., NU 37 y.) did not differ significantly. The time between trauma/surgery and ESWT was 4.2 months for DBH in healed and 3.7 months in non-healed without a significant difference, and 27 months for NU in both healed and non-healed. Age and smoking status also had no influence. The healing rate was highest at metacarpal bone/finger/thumb (91%), followed by forearm shaft (88%), epiphysis/metaphysis of the forearm (67%), and, lastly, carpal bones (59%). After conservative pre-treatment, 55% healed, compared with 67% after more than two previous surgeries, 73% without any pre-treatment, and 75% after one previous surgery. Further analysis of surgical pre-treatment showed 85% healing after ORIF alone, 64% without previous surgery, and 57% healing after ORIF with bone grafting/debridement. Intraoperative ESWT combined with bone debridement/transplantation and ORIF resulted in 67% healing, compared with 86% in combination with ORIF alone. ESWT alone or with only minimal measures (removal of osteosynthesis material) led to 70% consolidation. ESWT is equally effective at any stage of a bone healing disorder. The principles of stability and filling of bone defects must also be taken into account when using ESWT; then ESWT alone or combined with surgery is equally effective. The negative influence of bone defects/resorption is still detectable even with ESWT. Furthermore, treatment of the scaphoid is more problematic compared with other locations. Previous surgery is not a negative factor, even with osteosynthesis material in situ.

Ultrasound evaluation of radial nerve injuries by cortex overlapping screw tips after internal fixation of humeral fractures: a cadaveric study

PurposeThe radial nerve may be painfully irritated or damaged by open reduction and internal fixation (ORIF) of humeral fractures. Secondary radial nerve lesions after ORIF of humeral shaft fractures are described in up to 16%. Not only peripheral nerves but also orthopaedic instruments and osteosynthesis material are well visible by ultrasound. The aim of this study was to evaluate the accuracy of ultrasound in assessing the relation between the bone overlapping screw tips and the radial nerve close to the humeral bone.MethodsUltrasound-guided drilling was used to place screws as close as possible to the radial nerve in 8 humeral bones of four cadavers. The relation between the radial nerve and the screw tips was assessed by high-resolution ultrasound, and the overlap of all screw tips over the bone was measured by ultrasound and fluoroscopy. Thereafter, the findings were validated by anatomical dissection.ResultsWe could correctly identify all screw tips and their relation to the radial nerve by ultrasound. In 7 of 8 cases, the screw tip had direct contact with the radial nerve. The overlaying length of the screw tip was accurately measured by using ultrasound in all cases. In contrast fluoroscopy underestimated this length in 50% of cases.ConclusionWith this study, we show that ultrasound can reliable visualize the screw tips and its relation to the radial nerve. Ultrasound is a promising diagnostic tool to evaluate patients with radial nerve irritations or lesions after ORIF of humeral fractures. Furthermore, ultrasound could be an adequate tool to guide drilling.

Osteosynthesis for mandibular reconstruction with fibula free flap: Which type and why? A French national survey

We explored the most suitable osteosynthesis type for mandibular reconstruction using fibula free flap (FFF) given the lack of robust data available. For this, an anonymous survey was e-mailed to 853 head-and-neck surgeons (France) asking about their practices and criteria guiding their osteosynthesis material and method choices. Questions assessed: (1) the most frequently used osteosynthesis type, (2) the explanatory variables related to surgeon career status/surgical specialty, and (3) justifications for osteosynthesis type (scientific, technical, "misuse"). Multivariate logistic regression was performed to test for associations of explanatory variables with plate type or misuse. Overall, 118 (13.8%) surgeons responded, among which flexible non-locking osteosynthesis was preferred (59%). Career status and surgical specialty were significantly associated with material choice. University professors/senior lecturers (OR 5.96 vs academic clinical associates; p = 0.02), but not ear-nose-throat/reconstructive plastic surgeons (OR 0.22 vs maxillofacial surgeons; p = 0.04), were more likely to opt for rigid locking osteosynthesis. Private practitioners preferred flexible non-locking osteosynthesis (OR = 5.03; p = 0.04). Only 18% of surgeons scientifically justified their choices. We considered misuse among 65% of surgeons and this was significantly associated with irregular practice of FFF surgery (OR 2.28 vs > 10 surgeries/year; p = 0.04). Overall, >50% of surgeons mainly rely on habits without scientific arguments assisting in decision-making.

Management of Pediatric Elbow Fractures and Dislocations.

Pediatric elbow fractures and dislocations have always been a challenge from a diagnostic and therapeutic point of view, primarily due to the complex nature of the pediatric elbow, especially its developmental anatomy. They must be diagnosed and treated on time to prevent numerous complications with long-term consequences. With the development of radiology and pediatric surgery and orthopedics, as well as the development of modern osteosynthesis materials, concerning current scientific and professional knowledge, the outcomes are getting better, with fewer acute and chronic complications. This comprehensive review aims to provide clinicians current knowledge about pediatric elbow fractures and dislocations so that in daily practice they have as few doubts as possible with the best possible treatment outcomes.

Trauma of the midface : Symptoms, diagnostics and treatment

Midface fractures present aclinical challenge in otorhinolaryngology due to their often complex injury pattern and nonspecific symptoms. Precise diagnostics, including differentiated imaging procedures, are required. Interdisciplinary consultation between otorhinolaryngology, maxillofacial surgery, neurosurgery, and ophthalmology is often necessary. When selecting radiographic modalities, radiation hygiene should be taken into account. Sonography provides aradiation-free imaging alternative for fractures of the nasal framework and anterior wall of the frontal sinus. The goal of treatment is to achieve stable and symmetrical reconstruction. Depending on the injury pattern, different osteosynthesis materials, individual access routes, and various surgical procedures can be used. In clinical practice, the management of midface fractures requires amultidisciplinary, flexible, and pragmatic approach based on the fracture pattern and clinical experience.

Preliminary clinical and radiological evaluation of osteosynthesis using the Femoral Neck System (FNS) for subcapital fractures of the femur

Addressing subcapital fractures of the femur poses a substantial clinical challenge, complicated by the diverse range of available osteosynthesis materials. This study is dedicated to a comprehensive analysis of the clinical and radiological implications linked with the implementation of the Femoral Neck System (FNS) in osteosynthesis procedures. A descriptive study was conducted involving patients who underwent osteosynthesis for subcapital fractures of the femur utilizing the FNS during the period from 2019 to 2022. The investigation encompassed various facets, including the classification of fractures according to the Garden and Pauwells classifications, criteria for achieving precise reduction based on the Garden criteria and Tip Apex Distance (TAD). At the one-year follow-up, factors such as fracture consolidation, loss of reduction, fracture collapse, complications, and functional outcomes were evaluated utilizing the Harris Hip Score (HHS) scale. The study cohort included a total of 26 patients, among whom 22 exhibited non-displaced subcapital femur fractures categorized as Garden I and II. Successful reduction was accomplished in 23 cases, in which 24 cases (92.3%) displayed a TAD measurement below 25 mm. According to the HHS, patients achieved an average score of 90.9 (ranging from 63 to 100) following the surgical intervention, with predominantly "excellent" and "good" outcomes. The outcomes derived from our investigation corroborate the viability of the Femoral Neck System (FNS) as a reliable option for osteosynthesis in femoral neck fractures. The results obtained are comparable to those achieved with other available implants, as highlighted by previous studies.

Quantitative Assessment of Condylar Remodeling After Open Reduction and Internal Fixation in Mandibular Condylar Head Fractures.

Open reduction and internal fixation (OR/IF) and closed treatments are viable options, with OR/IF gaining popularity in mandibular condylar head fracture (CHF). Sufficient research is lacking on long-term condylar morphologic changes. This study quantitatively evaluated the morphologic changes in the condylar head in patients who underwent OR/IF for CHF without the removal of osteosynthesis material. A retrospective study analyzed patients who underwent OR/IF for CHF between November 2010 and August 2022. The transverse/lateral condyle width and condyle height were radiologically analyzed using panoramic and reverse Towne view x-ray images at immediate (T0), short-term (T1), and long-term (T2) postoperative periods. The study involved 29 patients with 32 surgically treated CHF. Long-term condyle height decreased significantly from 18.9±0.8mm at T0 to 18.1±0.8mm at T1 (P=0.042), and further to 17.3±0.7mm at T2 (P=0.034). Transverse width slightly reduced from 18.7±0.7mm at T0 to 17.9±0.8mm at T1 (P=0.001) but remained stable from T1 to T2 (17.6±1.0mm, P=0.756). Following surgery, maximal mouth opening averaged 39.5±6.1mm, with one case of chin deviation and three cases of joint pain. The condyle undergoes long-term shortening without altering its width. Nevertheless, patients experience favorable functional outcomes, including satisfactory mouth opening and occlusion. In addition, it is advisable not to remove the osteosynthesis material, as the remaining material causes minimal functional impairment and bone resorption.

Radiographic and complication evaluation of 2 different bioresorbable pins in hallux valgus corrective surgery.

Osteotomies to correct hallux valgus are usually secured using metal implants. Their main disadvantage is the need for a repeat surgery for removal of implanted material. Bioresorbable implants would make it possible to overcome this complication. Few studies analyse the results of using bioresorbable pins. The primary objective of this study is to compare hallux valgus correction radiographic results with the use of two types of bioresorbable pins. The secondary objectives are to screen for possible complications related to the use of these bioresorbable pins. This is a descriptive, retrospective, single-centre study carried out between May 2018 and May 2022 in the orthopaedic surgery department of the Centre Chirurgical Emile Gallé at the CHRU in Nancy (France). The study involved 105 hallux valgus (98 patients) operated on by open double metatarsal and phalangeal osteotomy. Osteotomies were stabilised with resorbable polylactic acid (PLLA) pins (Arthrex® TRIM-IT® drill pin) in 57 cases (53 patients), and with resorbable polylactic acid-polyglycolic acid copolymer (PGLA) pins (Bioretec® ActivaPins®) in 48 cases (45 patients). The efficacy of hallux valgus correction was analysed in terms of changes in preoperative and postoperative radiographic parameters at 1 and 6 months on a weight-bearing foot. Descriptive statistics were used to describe the demographic and radiological parameters of each group. The mean age was 59.7 years (range 25-81 years) in the PLLA group and 56 years (range 23-78 years) in the PGLA group. The mean preoperative HVA was 30° (range 15-63°) in the PLLA group and 30.8° (range 15-57°) in the PGLA group. The mean preoperative IMA was 14.4° (range 7-30°) in the PLLA group and 13.8° (range 7-20°) in the PGLA group. There was a statistically significant correction of hallux valgus in the PLLA (p=5.24 X 10-15 ) and PGLA (p=3.56 X 10-13 ) groups. The mean correction for the hallux valgus angle was 13° in the PLLA group and 12° in the PGLA group. There was no statistically significant difference in hallux valgus correction between the PLLA and PGLA groups, particularly in terms of hallux valgus severity. There was no radiological or clinical complication in the groups related to bioresorbable pins. The use of bioresorbable pins allows effective stabilisation of osteotomies to correct hallux valgus. There was no significant difference in correction between PLLA and PGLA implants, regardless of the severity of the hallux valgus. We did not observe any obvious clinical or radiological complications related to their use. The use of bioresorbable osteosynthesis material in forefoot surgery seems to offer interesting advantages, providing patients with safer and less invasive treatment solutions.

Correlation between Peripheric Blood Markers and Surgical Invasiveness during Humeral Shaft Fracture Osteosynthesis in Young and Middle-Aged Patients.

The treatment for humeral shaft fractures (HSFs) is still controversial, consisting of a wide variety of orthopedic osteosynthesis materials that imply different grades of invasiveness. The aim of this study is to investigate the correlation between inflammatory blood-derived markers and the magnitude of the surgical procedure in young and middle-aged patients who sustained these fractures. Observational, retrospective research was conducted between January 2018 and December 2023. It followed patients diagnosed with recent HFSs (AO/OTA 12-A and B) and followed operative treatment. They were split in two groups, depending on the surgical protocol: group A, operated by closed reduction and internal fixation (CRIF) with intramedullary nails (IMNs), and group B, operated by open reduction and internal fixation (ORIF) with dynamic compression plates (DCPs). Statistically significant differences (p < 0.05) between the two groups could be observed in injury on the basis of surgery durations, surgical times, pre- and postoperative neutrophil-per-lymphocyte ratio (NLR), postoperative platelet-per-lymphocyte ratio (PLR), monocyte-per-lymphocyte ratio (MLR), systemic inflammatory index (SII), systemic inflammatory response index (SIRI) and aggregate inflammatory systemic index (AISI). The multivariate regression model proposed revealed that NLR > 7.99 (p = 0.007), AISI > 1668.58 (p = 0.008), and the surgical times (p < 0.0001) are strongly correlated to the magnitude of the surgical protocol followed. Using receiver operating characteristic (ROC) curve analysis, a balanced reliability was determined for both postoperative NLR > 7.99 (sensitivity 75.0% and specificity 75.6) and AISI > 1668.58 (sensitivity 70.6% and specificity 82.2%). Postoperative NLR and AISI as inflammatory markers are highly associated with the magnitude of surgical trauma sustained during humeral shaft fracture osteosynthesis in a younger population.

What Is the Patient-reported Outcome and Complication Incidence After Operative Versus Nonoperative Treatment of Minimally Displaced Tibial Plateau Fractures?

Much controversy remains about whether minimally displaced tibial plateau fractures should be treated operatively or nonoperatively. It is generally accepted that gaps and stepoffs up to 2 mm can be tolerated, but this assumption is based on older studies using plain radiographs instead of CT to assess the degree of initial fracture displacement. Knowledge regarding the relationship between the degree of fracture displacement and expected functional outcome is crucial for patient counseling and shared decision-making, specifically in terms of whether to perform surgery. (1) Is operative treatment associated with improved patient-reported outcomes compared with nonoperative treatment in minimally displaced tibial plateau fractures (fractures with up to 4 mm of displacement)? (2) What is the difference in the risk of complications after operative versus nonoperative treatment in minimally displaced tibial plateau fractures? A multicenter, cross-sectional study was performed in patients treated for tibial plateau fractures between 2003 and 2019 at six hospitals. Between January 2003 and December 2019, a total of 2241 patients were treated for tibial plateau fractures at six different trauma centers. During that time, the general indication for open reduction and internal fixation (ORIF) was intra-articular displacement of > 2 mm. Patients treated with ORIF and those treated nonoperatively were potentially eligible; 0.2% (4) were excluded because they were treated with amputation because of severe soft tissue damage, whereas 4% (89) were excluded because of coexisting conditions that complicated outcome measurement including Parkinson disease, cerebrovascular accident, or paralysis (conditions causing an inability to walk). A further 2.7% (60) were excluded because their address was unknown, and 1.4% (31) were excluded because they spoke a language other than Dutch. Based on that, 1328 patients were potentially eligible for analysis in the operative group and 729 were potentially eligible in the nonoperative group. At least 1 year after injury, all patients were approached and asked to complete the Knee injury and Osteoarthritis Outcome Scale (KOOS) questionnaire. A total of 813 operatively treated patients (response percentage: 61%) and 345 nonoperatively treated patients (response percentage: 47%) responded to the questionnaire. Patient characteristics including age, gender, BMI, smoking, and diabetes were retrieved from electronic patient records, and imaging data were shared with the initiating center. Displacement (gap and stepoff) was measured for all participating patients, and all patients with minimally displaced fractures (gap or stepoff ≤ 4 mm) were included, leaving 195 and 300 in the operative and nonoperative groups, respectively, for analysis here. Multivariate linear regression was performed to assess the association of treatment choice (nonoperative or operative) with patient-reported outcomes in minimally displaced fractures. In the multivariate analysis, we accounted for nine potential confounders (age, gender, BMI, smoking, diabetes, gap, stepoff, AO/OTA classification, and number of involved segments). In addition, differences in complications after operative and nonoperative treatment were assessed. The minimum clinically important differences for the five subscales of the KOOS are 11 for symptoms, 17 for pain, 18 for activities of daily living, 13 for sports, and 16 for quality of life. After controlling for potentially confounding variables such as age, gender, BMI, and AO/OTA classification, we found that operative treatment was not associated with an improvement in patient-reported outcomes. Operative treatment resulted in poorer KOOS in terms of pain (-4.7 points; p = 0.03), sports (-7.6 points; p = 0.04), and quality of life (-7.8 points; p = 0.01) compared with nonoperative treatment, but those differences were small enough that they were likely not clinically important. Patients treated operatively had more complications (4% [7 of 195] versus 0% [0 of 300]; p = 0.01) and reoperations (39% [76 of 195] versus 6% [18 of 300]; p < 0.001) than patients treated nonoperatively. After operative treatment, most reoperations (36% [70 of 195]) consisted of elective removal of osteosynthesis material. No differences in patient-reported outcomes were observed at midterm follow-up between patients treated surgically and those treated nonsurgically for tibial plateau fractures with displacement up to 4 mm. Therefore, nonoperative treatment should be the preferred treatment option in minimally displaced fractures. Patients who opt for nonoperative treatment should be told that complications are rare, and only 6% of patients might undergo surgery by midterm follow-up. Patients who opt for surgery of a minimally displaced tibial plateau fracture should be told that complications may occur in up to 4% of patients, and 39% of patients may undergo a secondary intervention (most of which are elective implant removal). Level III, therapeutic study.

Resorbable Patient-Specific Implants of Molybdenum for Pediatric Craniofacial Surgery-Proof of Concept in an In Vivo Pilot Study.

Titanium continues to be the gold standard in the field of osteosynthesis materials. This also applies to pediatric craniofacial surgery. Various resorbable materials have already been developed in order to avoid costly and risky second operations to remove metal in children. However, none of these resorbable materials have been able to completely replace the previous gold standard, titanium, in a satisfactory manner. This has led to the need for a new resorbable osteosynthesis material that fulfills the requirements for biocompatibility, stability, and uniform resorption. In our previous in vitro and in vivo work, we were able to show that molybdenum fulfills these requirements. To further confirm these results, we conducted a proof of concept in four domestic pigs, each of which was implanted with a resorbable molybdenum implant. The animals were then examined daily for local inflammatory parameters. After 54 days, the animals were euthanized with subsequent computer tomography imaging. We also removed the implants together with the surrounding tissue and parts of the spleen, liver, and kidney for histopathological evaluation. The molybdenum implants were also analyzed metallographically and using scanning electron microscopy. A blood sample was taken pre- and post-operatively. None of the animals showed clinical signs of inflammation over the entire test period. Histopathologically, good tissue compatibility was found. Early signs of degradation were observed after 54 days, which were not sufficient for major resorption. Resorption is expected with longer in situ residence times based on results of similar earlier investigations.

Stable fixation using absorbable sutures in craniofacial surgery in patients over 24 months of age—a retrospective study

PurposeIn craniofacial surgery, the stable fixation of transposed bone segments is crucial in order to ensure good long-term results. The use of absorbable material in fixation avoids the need for a second surgery, which would otherwise be required to remove osteosynthesis material. The authors of the present manuscript have already demonstrated that absorbable sutures ensure the stable fixation of bone segments in patients up to 24 months of age. However, it has thus far remained unclear whether stable fixation is possible in older patients by using only absorbable sutures due to the slower bone remodelling and prolonged healing time in this cohort.MethodFor the present study, osteosynthesis was performed in 50 patients ranging from 25.7 to 192.1 months of age (mean, 61.4 ± 21.7 months) using solely absorbable sutures (PDS II®, Ethicon, Germany). Post-operative stability and possible restrictions—such as foreign body reactions—were evaluated within clinical and radiological routine follow-ups.ResultsAll children demonstrated clinically and radiologically stable osteosynthesis both directly post-operatively and in follow-ups. No significant foreign body reaction could be seen.ConclusionThe present study demonstrates—for the first time—that absorbable sutures with a longer absorption period are also very well suited for the fixation of bone segments in patients over 24 months of age. The sole use of absorbable sutures in children over 24 months of age is a safe procedure with nearly no foreign body reactions. The procedure enables stable and highly cost-effective osteosynthesis without altering the osteotomy design.

Ultrasonically induced electrical potentials in PLLA film and bone

Osteosynthesis materials are used for the fixed treatment of serious bone fractures. Titanium and bioabsorbable poly-L-lactic acid (PLLA) are often used. PLLA is known to have piezoelectricity, and its contribution to bone fracture healing has been discussed. On the other hand, bone fracture healing using low-intensity-pulsed-ultra-sound (LIPUS) is also popular although the initial mechanism (how bones sense ultrasound) is still unclear. One key factor is the weak piezoelectricity of bone. If ultrasound was able to induce higher electrical potentials in PLLA than in bone, the combination treatment of PLLA and LIPUS would be effective for bone fracture healing. Then, we experimentally investigated the piezoelectricity of PLLA and bone in the MHz range. First, we fabricated an ultrasonic receiver using a cortical bone plate (thickness 1 mm) covered by a stretched PLLA film (thickness 50 mm) as a piezoelectric material. Second, we irradiated ultrasound in the MHz range to the receiver and measured electrical potentials as the output of the receiver. As a result, the average electrical potentials were about 1.4 times higher than those of a receiver made of bone without the PLLA film. This result indicates that ultrasonically induced potentials around bone may increase by the PLLA film.

Outcomes and influencing factors of dental implants in fibula, iliac crest, and scapula free flaps: a retrospective case–control study

PurposeReconstruction with vascularized bone grafts after ablative surgery and subsequent dental rehabilitation with implants is often challenging; however, it helps improve the patient’s quality of life. This retrospective case–control study aimed to determine the implant survival/success rates in different vascularized bone grafts and potential risk factors.MethodsOnly patients who received implants in free vascularized bone grafts between 2012 and 2020 were included. The free flap donor sites were the fibula, iliac crest, and scapula. The prosthetic restoration had to be completed, and the observation period had to be over one year after implantation. Implant success was defined according to the Health Scale for Dental Implants criteria.ResultsSixty-two patients with 227 implants were included. The implant survival rate was 86.3% after an average of 48.7 months. The causes of implant loss were peri-implantitis (n = 24), insufficient osseointegration (n = 1), removal due to tumor recurrence (n = 1), and osteoradionecrosis (n = 5). Of all implants, 52.4% were classified as successful, 19.8% as compromised, and 27.8% as failed. Removal of osteosynthesis material prior to or concurrent with implant placement resulted in significantly better implant success than material not removed (p = 0.035). Localization of the graft in the mandibular region was associated with a significantly better implant survival (p = 0.034) and success (p = 0.002), also a higher Karnofsky Performance Status Scale score with better implant survival (p = 0.014).ConclusionImplants placed in vascularized grafts showed acceptable survival rates despite the potential risk factors often present in these patient groups. However, peri-implantitis remains a challenge.Graphical abstract

Refinement in Post-Operative Care for Orthopaedic Models: Implementing a Sheep Walking Cast (SWC) for Effective Tibial Fracture Management.

In the healthcare system, lower leg fractures remain relevant, incurring costs related to surgical treatment, hospitalization, and rehabilitation. The duration of treatment may vary depending on the individual case and its severity. Casting as a post-surgical fracture treatment is a common method in human and experimental veterinary medicine. Despite the high importance of sheep in preclinical testing materials for osteosynthesis, there is no standardised cast system ensuring proper stabilisation and functionality of hind limbs during the healing of tibia fractures or defects. Existing treatment approaches for tibial osteosynthesis in laboratory animal science include sling hanging, external fixators, or former Achilles tendon incision. These methods restrict animal movement for 4-6 weeks, limit species-typical behaviour, and impact social interactions. Our pilot study introduces a Standardised Walking Cast (SWC) for sheep, enabling immediate physiological movement post surgery. Seven Rhone sheep (female, 63.5 kg ± 6.45 kg) each with a single tibia defect (6 mm mechanical drilled defect) underwent SWC application for 4 weeks after plate osteosynthesis. The animals bore weight on their operated leg from day one, exhibiting slight lameness (grade 1-2 out of 5). Individual step lengths showed good uniformity (average deviation: 0.89 cm). Group housing successfully started on day three after surgery. Weekly X-rays and cast changes ensured proper placement, depicting the healing process. This study demonstrates the feasibility of using an SWC for up to 72 kg of body weight without sling hanging via ceiling mounting or external fixation techniques. Allowing species-typical movement and social behaviour can significantly improve the physiological behaviour of sheep in experiments, contributing to refinement.

Arthroscopic Subtalar Distraction Arthrodesis in Post-Traumatic Indications

This manuscript aims to present the method of arthroscopic assisted subtalar arthrodesis and to evaluate the benefi ts of this surgery on our study population. In the period from 9/2007 to 1/2020, a total of 33 subtalar arthrodesis were performed in 31 patients aged 19-66 years (mean 48 years, median 50 years). The indication for arthrodesis was subtalar arthritis causing pain and gait disorders, or hindfoot deformities (most commonly after a calcaneus bone fracture). The arthroscopic assisted subtalar arthrodesis was performed with autologous tricortical bone block graft harvesting from the pelvis, supplemented by autologous cancellous bone graft. Stabilization was achieved by cannulated screws inserted in neutral ankle position. Patients in our retrospective study were followed up for a mean of 48 months (range, 24-130 months). The patients were evaluated preoperatively and at 2 years after surgery. The hindfoot angles and height (TCA - talocalcaneal angle, CIA - calcaneal inclination angle, TCH - talocalcaneal height) were evaluated on radiographs, bone union was assessed on radiographs and CT scans. The clinical assessment was performed using the ankle-hindfoot scale (AHS) of AOFAS (AOFAS score). The preoperative AOFAS score was 35-68 points (mean 52, median 54), the postoperative AOFAS score at 2 years after arthrodesis was 58-94 points (mean 82, median 82). Both the mean and median values of AOFAS score showed a signifi - cant progress from the poor result to the good and excellent result. After 2 years the TCA value decreased in 18 patients (56%) by no more than 3°. The CIA decrease observed in 21 patients (64%) was by 1° on average. The TCH decrease of 1-5 mm after 2 years since the surgery was seen in 16 patients. In 2 patients incomplete healing of arthrodesis was observed, manifested as a clinically asymptomatic non-union. No deep infection was reported. In agreement with the current literature, the arthroscopic subtalar arthrodesis has been confi rmed to be a safe method for the management of consequences of hindfoot fractures, with minimum complications and leading to accelerated bone fusion. Differences can be found in the approach, position, use of cancellous bone graft and surgical techniques. In recent years, prone position, posterior approaches, use of cancellous bone graft, distraction and fi xation with 2-3 screws divergently inserted into the bone prevail. The degree of healing of the bone fusion is generally an important factor. In our study population, non-healing was recorded in 2 patients, namely in the form of a clinically silent non-union. Neurological or early complications and/or osteosynthesis material failure occurred in up to a maximum of 10% of cases. The conclusive results of minimally invasive arthrodesis based on the AOFAS score have been confi rmed by us as well as by most authors. Our study confi rmed that the arthroscopic assisted subtalar arthrodesis is a successful, reliable and safe minimally invasive method, with minimum complications, leading to stable arthrodesis. subtalar arthrodesis, subtalar arthroscopy.