Applying 3D-printed prostheses to reconstruct critical-sized bone defects of tibial diaphysis (> 10 cm) caused by osteomyelitis and aseptic non-union.

BACKGROUND: Clinical repair of critical-sized bone defects (CBDs) in the tibial diaphysis presents numerous challenges, including inadequate soft tissue coverage, limited blood supply, high load-bearing demands, and potential deformities. This study aimed to investigate the clinical feasibility and efficacy of employing 3D-printed prostheses for repairing CBDs exceeding 10 cm in the tibial diaphysis. METHODS: This retrospective study included 14 patients (11 males and 3 females) with an average age of 46.0 years. The etiologies of CBDs comprised chronic osteomyelitis (10 cases) and aseptic non-union (4 cases), with an average defect length of 16.9 cm. All patients underwent a two-stage surgical approach: (1) debridement, osteotomy, and cement spacer implantation; and (2) insertion of 3D-printed prostheses. The interval between the two stages ranged from 8 to 12 weeks, during which the 3D-printed prostheses and induced membranes were meticulously prepared. Subsequent to surgery, patients engaged in weight-bearing and functional exercises under specialized supervision. Follow-up assessments, including gross observation, imaging examinations, and administration of the Lower Extremity Functional Scale (LEFS), were conducted at 3, 6, and 12 months postoperatively, followed by annual evaluations thereafter. RESULTS: The mean postoperative follow-up duration was 28.4 months, with an average waiting period between prosthesis implantation and weight-bearing of 10.4 days. At the latest follow-up, all patients demonstrated autonomous ambulation without assistance, and their LEFS scores exhibited a significant improvement compared to preoperative values (30.7 vs. 53.1, P < 0.001). Imaging assessments revealed progressive bone regeneration at the defect site, with new bone formation extending along the prosthesis. Complications included interlocking screw breakage in two patients, interlocking screw loosening in one patient, and nail breakage in another. CONCLUSIONS: Utilization of 3D-printed prostheses facilitates prompt restoration of CBDs in the tibial diaphysis, enabling early initiation of weight-bearing activities and recovery of ambulatory function. This efficacious surgical approach holds promise for practical application.

Medial cortical bone thickness of the tibial diaphysis in osteoarthritis is related to lower extremity alignment and tibial morphology.

BACKGROUND: The purpose of this study was to clarify (1) the differences in cortical bone thickness (CBT) of the tibial diaphysis between healthy and osteoarthritic knees and (2) the influences of the femorotibial angle (FTA) and inclination of the medial compartment of the proximal tibia (MCT) on tibial CBT. METHODS: The study assessed 60 subjects with varus knee osteoarthritis (OA) (22 males and 38 females; mean age, 74 ± 7 years) and 53 healthy elderly subjects (28 males and 25 females; mean age, 70 ± 6 years). Three-dimensional estimated CBT of the tibial diaphysis was automatically calculated for 2752-11,296 points using high-resolution measurements from CT. The standardized CBT was assessed in 24 regions by combining six heights and four areas. Additionally, the association between the CBT, each FTA, and MCT inclination was investigated. RESULTS: The OA group showed a thicker CBT in the medial areas than in the lateral areas of the proximal tibia, while the healthy group had a thicker lateral CBT. The medial-to-lateral ratio of the proximal tibia was significantly higher in the OA group than in the healthy group. The proximal-medial CBT correlated with FTA and MCT inclinations in the OA group. CONCLUSIONS: This study demonstrated that varus osteoarthritic knees showed a different trend of proximal-medial CBT with associations in FTA and MCT inclination from healthy knees, possibly due to medial load concentration.

Enriched mesoporous bioactive glass scaffolds as bone substitutes in critical diaphyseal bone defects in rabbits.

In the field of orthopedic surgery, there is an increasing need for the development of bone replacement materials for the treatment of bone defects. One of the main focuses of biomaterials engineering are advanced bioceramics like mesoporous bioactive glasses (MBG´s). The present study compared the new bone formation after 12 weeks of implantation of MBG scaffolds with composition 82,5SiO2-10CaO-5P2O5-x 2.5SrO alone (MBGA), enriched with osteostatin, an osteoinductive peptide, (MBGO) or enriched with bone marrow aspirate (MBGB) in a long bone critical defect in radius bone of adult New Zealand rabbits. New bone formation from the MBG scaffold groups was compared to the gold standard defect filled with iliac crest autograft and to the unfilled defect. Radiographic follow-up was performed at 2, 6, and 12 weeks, and microCT and histologic examination were performed at 12 weeks. X-Ray study showed the highest bone formation scores in the group with the defect filled with autograft, followed by the MBGB group, in addition, the microCT study showed that bone within defect scores (BV/TV) were higher in the MBGO group. This difference could be explained by the higher density of newly formed bone in the osteostatin enriched MBG scaffold group. Therefore, MBG scaffold alone and enriched with osteostatin or bone marrow aspirate increase bone formation compared to defect unfilled, being higher in the osteostatin group. The present results showed the potential to treat critical bone defects by combining MBGs with osteogenic peptides such as osteostatin, with good prospects for translation into clinical practice. STATEMENT OF SIGNIFICANCE: Treatment of bone defects without the capacity for self-repair is a global problem in the field of Orthopedic Surgery, as evidenced by the fact that in the U.S alone it affects approximately 100,000 patients per year. The gold standard of treatment in these cases is the autograft, but its use has limitations both in the amount of graft to be obtained and in the morbidity produced in the donor site. In the field of materials engineering, there is a growing interest in the development of a bone substitute equivalent. Mesoporous bioactive glass (MBG´s) scaffolds with three-dimensional architecture have shown great potential for use as a bone substitutes. The osteostatin-enriched Sr-MBG used in this long bone defect in rabbit radius bone in vivo study showed an increase in bone formation close to autograft, which makes us think that it may be an option to consider as bone substitute.

Fracture pattern analysis of fractures to the diaphysis of the fifth metatarsal.

BACKGROUND: Fractures to the fifth's metatarsal (MT-V) diaphysis are common. These are inconsistently referred to as diaphyseal-, shaft-, or Dancer's fractures. A comprehensive analysis of the MT-V fracture morphology is missing. The aim was to qualitatively and quantitatively analyze fracture patterns of MT-V diaphyseal fractures. HYPOTHESIS: Fractures to the shaft of the fifth metatarsal feature specific fracture morphologies. MATERIALS AND METHODS: Retrospective, radiologic database study. Included were all acute, isolated MT-V shaft fractures (including the proximal [Lawrence and Botte (L&B) III] and distal meta-diaphysis). Demographics and fracture characteristics were assessed. Each proximal fracture line was drawn, scaled, and a qualitative and quantitative fracture line analysis was conducted. The quantitative fracture line analysis aimed at identifying dens clusters with arbitrary shape using the DBSCAN algorithm. Data are presented as mean±standard deviation. RESULTS: Out of 704 eligible MT-V fractures, 156 met the inclusion criteria. Patient's mean age was 46±19 years and 94% suffered a low energy trauma. Qualitative and quantitative fracture line analysis revealed three distinct fracture patterns. The proximal (30%) and distal (5%) meta-diaphyseal clusters showed a predominant transverse fracture pattern. The vast majority of diaphyseal fractures (56%) were spiral/oblique fractures, progressing from the proximal lateral meta-diaphyseal region in an oblique course at 61±9° to the medial distal diaphyseal cortex. Seven percent of diaphyseal fractures showed a transverse fracture pattern. DISCUSSION: Based on a qualitative and quantitative analysis of all MT-V shaft fractures, three distinct fracture clusters were identified with homogeneous fracture patterns. MT-V shaft fractures should therefore be classified as proximal meta-diaphyseal (L&B Type III), diaphyseal (oblique or transverse) and distal meta-diaphyseal. LEVEL OF PROOF: IV; retrospective database study.

Femoral Neck Preservation and Diaphyseal Invasion Comparing a Calcar-Metaphyseal Short Stem with its Homonymous Standard Femoral Stem. A Radiographic Study.

BACKGROUND: We aim to compare the preoperative planning radiographs of 50 patients in whom both a short stem and its homonymous standard version were programmed, focusing on the preservation of the neck and the invasion of the femoral shaft. The secondary objective was to evaluate the 50 preoperative radiographs with the 50 postoperative radiographs in which the short stem was implanted, measuring the real invasion of the diaphysis and the real preservation of the femoral neck. MATERIAL AND METHODS: We measured cut level at the femoral neck and diaphyseal invasion in 50 preoperative x-rays where an Alteon Neck Preserving Stem (ANPS) was templated and we compared it with 50 preoperative x-rays where an Alteon Taper Wedge Stem (ATWS) was templated. After surgery, we compared both parameters previously measured in the preoperative x-rays with the 50 postoperative radiographs where the short stem was implanted obtaining the real bone preservation at the femoral neck and the real diaphyseal invasion length. RESULTS: For templating comparison, mean bone preservation at the femoral neck was 14.87mm (SD 3.64) for the ANPS group and 9.94mm (SD 8.39) for the ATWS group (p <0.001). The mean diaphyseal bone invasion was 47.21mm (SD 5.89) and 76.77mm (SD 8.39) for ANPS and ATWS respectively (p <0.001). After surgery, the mean postoperative bone preservation at the femoral neck was 15.08mm (SD 3.1) with a mean of 0.17mm (SD 0.51) more preservation in the preoperative group. CONCLUSION: 1. ANPS allow bone preservation with limited diaphyseal invasion when compared with his homonymous ATWS in the preoperative templates. 2. ANPS showed a good correlation between preoperative radiographs and real bone preservation of the femoral neck and invasion of the femoral shaft.

Metaphyseal and Diaphyseal Contours: Variants and Pitfalls.

We discuss several variants of the metaphyseal and diaphyseal bone surfaces that may be misleading in clinical practice. They include metaphyseal stripes, spiculated metaphyseal cortex, cortical desmoid, laminated lateral supracondylar ridge, cortical vascular canals, variations in shape or lucency of normal tuberosities, cortical thickening of normal ridges, and well-organized undulated hyperostosis at the proximal phalanges.

Regional and temporal variation in bone loss during the first year following spinal cord injury.

Osteoporosis is a consequence of spinal cord injury (SCI) that leads to fragility fractures. Visual assessment of bone scans suggests regional variation in bone loss, but this has not been objectively characterised. In addition, substantial inter-individual variation in bone loss following SCI has been reported but it is unclear how to identify fast bone losers. Therefore, to examine regional bone loss, tibial bone parameters were assessed in 13 individuals with SCI (aged 16-76 years). Peripheral quantitative computed tomography scans at 4 % and 66 % tibia length were acquired within 5 weeks, 4 months and 12 months postinjury. Changes in total bone mineral content (BMC), and bone mineral density (BMD) were assessed in ten concentric sectors at the 4 % site. Regional changes in BMC and cortical BMD were analysed in thirty-six polar sectors at the 66 % site using linear mixed effects models. Relationships between regional and total loss at 4 months and 12 months timepoints were assessed using Pearson correlation. At the 4 % site, total BMC (P = 0.001) decreased with time. Relative losses were equal across the sectors (all P > 0.1). At the 66 % site, BMC and cortical BMD absolute losses were similar (all P > 0.3 and P > 0.05, respectively) across polar sectors, but relative loss was greatest in the posterior region (all P < 0.01). At both sites, total BMC loss at 4 months was strongly positively associated with the total loss at 12 months (r = 0.84 and r = 0.82 respectively, both P < 0.001). This correlation was stronger than those observed with 4-month BMD loss in several radial and polar sectors (r = 0.56-0.77, P < 0.05). These results confirm that SCI-induced bone loss varies regionally in the tibial diaphysis. Moreover, bone loss at 4 months is a strong predictor of total loss 12 months postinjury. More studies on larger populations are required to confirm these findings.

Periosteal reaction-like lesions at the cranial aspect of the humeral diaphysis have a high prevalence in older, large breed dogs and may represent entheses of the superficial pectoral muscles.

Authors have commonly observed lamellar periosteal new bone formation at the cranial aspect of the humeral diaphysis in mediolateral radiographs of the humerus for large breed dogs with no evidence of pain or lameness. The aim of this retrospective, analytical study was to investigate the appearance and prevalence of "humeral periosteal reaction-like lesions" (HPRLL) in dogs and identify any predispositions. Mediolateral radiographs of humeri were evaluated and the presence and extent of "humeral periosteal reaction-like lesions" at the cranial aspect of the humerus were recorded. Macroscopic and histological examination of the humeri were performed for one dog with HPRLL. A total of 2877 mediolateral radiographs of 1727 dogs were included and focal or extended periosteal reaction-like lesions were found in 643 humeri of 387 dogs. Body weight ≥ 30 kg and age ≥ 7 years had a statistically significant, positive effect (P < 0.001) on the presence of HPRLL. German Shepherd dogs and Rottweilers were overrepresented in the group with HPRLL (P < 0.01). At the level of the HPRLL, the enthesis of the superficial pectoral muscles (M. pectoralis descendens and M. pectoralis transversus) to the Crista tuberculi majoris and Crista humeri were macroscopically and histologically identified. The authors propose that higher mechanical loads to the enthesis in large breed dogs may lead to physiological, age-related remodeling processes of the muscular attachment. The finding should not be confused with a pathological condition such as bone neoplasia.

Fracture edge features of diaphyseal clavicular fractures: a morphologic study.

BACKGROUND: Previous researchers used transverse fractures centered over the midpoint of the clavicle as the diaphyseal clavicular fracture models. However, as a result of shear stress concentration in sigmoid-shaped structures, most diaphyseal clavicular fractures have coronal fracture edges and are located distal to the midpoint. The purpose of this study was to quantify the morphology and utilize these parameters to establish clinically relevant fracture models. METHODS: The computed tomographic DICOM data of 100 consecutive patients were included. We investigated the morphologic characteristics of the fracture edges after virtual fracture reduction. The fracture orientation was determined based on the normal vectors of the best-fit plane of the fracture edges. The fracture location was measured by the extreme points of the edges. The fracture configuration was evaluated using fracture maps. RESULTS: There were 28 simple, 43 wedge, and 29 multifragmentary types. Coronal oriented fracture edges accounted for more than 70% of the simple, wedge, and multifragmentary types. The most proximal point of the proximal edge was located at 46.7% (42.0%-56.5%), 47.6% (42.5%-50.1%), and 46.3% (42.0%-49.3%) of the endpoint line in the simple, wedge, and multifragmentary types, respectively (P = .548). The most distal point of the distal edge was located at 72.2% (68.4%-75.0%), 73.2% (69.5%-76.9%), and 74.0% (69.6%-77.1%) of the endpoint line (P = .353). The longest proximal main fragments occurred in the simple types at 71.9% (66.3%-75.4%) of the endpoint line (P < .001), and the shortest distal main fragments occurred in the multifragmentary types at 55.8% (49.8%-59.3%) of the endpoint line (P = .001). The heatmaps showed a high concentration of anteriorly distributed wedge fragments (88%; n = 38/43) and coronally distributed multifragmentary fragments (62%; n = 18/29). CONCLUSIONS: We showed that typical diaphyseal clavicular fractures have coronal fracture edges and are located within the distal half of the diaphyseal segment. The fractured fragments were initiated anteriorly in the wedge types and then propagated coronally in the multifragmentary types. The features of these fracture edges could be useful in designing osteotomy models and provide different perspectives of anterior and superior plating techniques.

Plate Fixation for Atypical Fractures of the Femoral Diaphysis.

Background: Plate fixation for atypical femoral fractures has shown high failure rates compared to intramedullary nail fixation. The aim of this study was to evaluate the radiological results of patients treated with a plate and screws for atypical fractures of the femoral diaphysis. Methods: This study was conducted retrospectively on 16 patients who had undergone internal fixation using plates for treatment of atypical femoral complete fractures from 2007 to 2015. Nine patients were treated with lag screws and short plates while 7 patients were treated with position screws and long plates, which covered the whole femur. Radiologic evaluation was performed on all patients. Complications were also evaluated. Results: Bone union was achieved in all patients and the average bone union time was 17.7 weeks (range, 14-28 weeks). There was no correlation between the preoperative use of a bisphosphonate, plate length, postoperative teriparatide use, and the time to bone union. Regarding complications, 2 cases of complete fractures and 1 impending fracture occurred at the end of short plates. Conclusions: Satisfactory results were obtained with use of plates for patients with atypical femoral complete diaphyseal fractures, in whom intramedullary nails could not be applied due to severe bowing. In particular, it seemed advantageous compared with intramedullary nail fixation in that it could maintain the leg length through anatomical reduction and prevent iatrogenic fracture.

Intra-Observational and Inter-Observer Agreement of The Radiographic Humerus Union Measurement (RHUM) in Patients Treated with Dynamic Compression Plate for Humeral Shaft Nonunion.

BACKGROUND: It is important for orthopedic surgeons to follow the union of the fracture after surgery. This becomes even more important after nonunion surgery. The radiological union scale is popular in the follow-up of unions. However, the intraobserver and interobserver agreement of this scale in humeral nonunion surgery is still not found in the literature. OBJECTIVE: This study aimed to reveal the intra/interobserver agreement of the Radiographic Union scale (RHUM) for the humerus as well as the relationship between this agreement, plate placement characteristics, and the number of plates in cases where plates were used for surgical treatment of humeral diaphysis nonunion. MATERIALS AND METHODS: Twenty patients who received surgical treatment for aseptic humeral nonunion at our hospital between 2010-2019 were studied retrospectively. According to RHUM, two observers scored the patients' anteroposterior and lateral radiographs in the postoperative 12th week. The data obtained were statistically analyzed. RESULTS: The mean age was 52.05±15.88 years. While a single plate was used in 14 cases, a double plate was used in 6 cases. Interobserver agreement was fair-moderate. The interobserver agreement values of the single plate group were significantly higher than those of the double plate group (p<0.05). Interobserver agreement in cases with a lateral plate was significantly higher than in the group where the lateral + posterior plate was applied (p:0.01). CONCLUSION: In humeral diaphyseal fracture nonunion cases, the number and location of the plate following surgery negatively impact the evaluation of RHUM scores. Given the importance of the union's follow-up and the decision to proceed with additional treatment in these cases, it may be necessary to develop a new method for determining and monitoring the union if a plate was used in the surgical treatment of humeral nonunion.

Biomechanical analysis of the correlation between mid-shaft atypical femoral fracture (AFF) and axial varus deformation.

BACKGROUND: Atypical femoral fractures (AFF) are diaphyseal fractures of the elderly that occur at the end of a minor trauma. The objective of this biomechanical study, using finite element modelling, was to evaluate the variations of the femoral diaphysis fracture indicator according to the variations of the mechanical axis of the lower limb, which can explain all the different atypical fracture types identified in the literature. METHODS: In order to measure variations in stress and risk factors for fracture of the femoral diaphysis, the distal end of the femur was constrained in all degrees of freedom. An axial compression load was applied to the femoral head to digitally simulate the bipodal support configuration in neutral position as well as in different axial positions in varus/valgus (- 10°/10°). RESULTS: The maximum stress value of Von Mises was twice as high (17.96 ± 4.87 MPa) at a varus angle of - 10° as in the neutral position. The fracture risk indicator of the femoral diaphysis varies proportionally with the absolute value of the steering angle. However, the largest simulated varus deformation (- 10°) found a higher risk of diaphysis fracture indicator than in valgus (10°). CONCLUSIONS: Variations in the mechanical axis of the lower limb influence the stress distribution at the femur diaphysis and consequently increase the risk of AFF. The axial deformation in varus is particularly at risk of AFF. The combination of axial deformation stresses and bone fragility consequently contribute to the creation of an environment favorable to the development of AFF. TRIAL REGISTRATION: 'retrospectively registered'.

Radiographic Determination of the Distal Ulnar Diaphyseal Angle.

PURPOSE: Characterizing the distal ulnar diaphyseal angle (DUDA) may be important for anatomic recreation of the distal ulna during ulnar shortening osteotomy procedures using conventional straight plates. This study characterized the DUDA and determined side-to-side, age, and sex effects on DUDA magnitudes and locations. METHODS: Retrospective analyses of bilateral wrist radiographs were performed on 60 patients. The DUDA was defined as the angle of intersection between a line passing through the center of the distal ulnar metadiaphyseal region, in line with the landmarked long axis of the ulna, on a lateral radiograph. This inflection point was measured from the most distal aspect of the ulnar head and recorded as the DUDA tip-to-apex distance (TAD). Rater reliability was determined using the intraclass correlation coefficient. RESULTS: We found DUDAs in 94% of radiographs. The mean DUDA angle was 5.6° ± 2.6° and the mean TAD was 45.3 ± 9.5 mm. The Pearson correlation coefficients for side-to-side comparisons were 0.47 for the DUDA angle and 0.69 for the TAD. For male and female patients, the mean DUDAs were 5.4° ± 2.3° and 5.9° ± 2.9°, respectively, and the mean TADs were 47.8 ± 9.7 mm and 41.7 ± 7.9 mm, respectively. The DUDA angle and TAD had negligible associations with age (r = -0.15 and -0.08, respectively). At 0.74 (95% CI, 0.58-0.85), interrater reliability was good. At 0.93 (95% CI, 0.88-0.96), intrarater reliability was excellent. CONCLUSIONS: We demonstrated DUDAs, representing valgus deviations from the center axis and anteroposterior views of the ulna. Contralateral lateral wrist radiographs are moderate to strongly reliable in determining a DUDA. Rater reliability was good to excellent. CLINICAL RELEVANCE: Re-creation of the DUDA may benefit procedures such as ulnar shortening osteotomy, fractures, or malunion by contributing to knowledge of distal radioulnar joint biomechanics.

Epidemiology of proximal and diaphyseal humeral fractures in children: an observational study from the Swedish Fracture Register.

BACKGROUND: Most fractures in children are fractures of the upper extremity. Proximal and diaphyseal humeral fractures account for a minority of these fractures. To our knowledge, few previous reports address these fractures. This study aimed to describe the epidemiology and current treatment of proximal and diaphyseal humeral fractures by using the Swedish Fracture Register (SFR). METHODS: In this nationwide observational study from the SFR we analysed data on patient characteristics, injury mechanism, fracture classification and treatment. We included patients aged < 16 years at time of injury with proximal or diaphyseal humeral fracture registered in 2015-2019. RESULTS: 1996 (1696 proximal and 300 diaphyseal) fractures were registered. Proximal fractures were more frequent in girls whereas diaphyseal fractures were more frequent in boys. The median age at fracture was 10 years in both fracture types but patient's age was more widespread in diaphyseal fracture (IQR 5-13 compared to IQR 7-12 in proximal). In both sexes, the most registered injury mechanism was fall. Horse-riding was a common mechanism of injury in girls, whereas ice-skating and skiing were common mechanisms in boys. Most proximal fractures were metaphyseal fractures. Most diaphyseal fractures were simple transverse or oblique/spiral fractures. The majority of fractures were treated non-surgically (92% of proximal and 80% of diaphyseal fractures). The treatment method was not associated with the patient's sex. Surgery was more often performed in adolescents. The most common surgical methods were K-wire and cerclage fixation in proximal fracture and intramedullary nailing in diaphyseal fracture. CONCLUSION: Following falls, we found sex-specific sport activities to cause most proximal and diaphyseal paediatric fractures. Further studies on prophylactic efforts in these activities are needed to investigate whether these fractures are preventable. The majority of the fractures were treated non-surgically, although surgical treatment increased with increasing age in both sexes. TRIAL REGISTRATION: Not applicable. The present study is a register-based cohort study. No health care intervention had been undertaken.

Closed reduction and locked intramedullary nailing of diaphyseal long bone fractures without intra-operative imaging and fracture table.

PURPOSE: Early closed reduction and locked intramedullary (IM) nailing has become the standard treatment for diaphyseal long bone fractures in high income countries. The low and middle income countries (LMICs) are still lagging behind in transiting from open surgical reduction and non-operative modalities to closed reduction due to lack of requisite equipment. However, some surgeons in LMICs are beginning to achieve closed reduction even without the equipment. METHODS: A prospective descriptive study was done on a total of 251 fresh diaphyseal fractures of the humerus, femur and tibia fixed with a locked nail over a 5½-year period. The fractures were grouped into those that had open reduction, closed reduction or reduction with a finger. RESULTS: Closed reduction was done for 135 (53.8%) fractures belonging to 123 patients. The mean and range of the patients' ages were 41.33 and 13-81 years, respectively. Males constituted 69.9% and mostly (48%) sustained fractures in motorcycle accident. There was a significant negative association between closed reduction and fracture-to-surgery interval (p < 0.001). Closed reduction also had positive associations with: (i) humerus and tibia fractures (p < 0.001), (ii) middle, distal and segmental fractures (p = 0.025), (iii) retrograde approach to femur fracture nailing (p < 0.001), and (iv) wedge or multifragmentary type femur fractures (p = 0.005). CONCLUSION: With constant practice, it is possible to achieve closed reduction of many fresh diaphyseal long bone fractures in spite of the limitations imposed on surgeons in LMICs by poor health systems and grossly inadequate fracture care facilities.

Local heat generation during screw insertion into diaphyseal bone: a biomechanical study on different conditions (e.g. screw type, material, mode of insertion).

BACKGROUND: The implantation of screws is a standard procedure in musculoskeletal surgery. Heat can induce thermal osteonecrosis, damage the bone and lead to secondary problems like implant loosening and secondary fractures. The aim of this study was to investigate whether screw insertion generates temperatures that can cause osteonecrosis. METHODS: We measured the temperature of twenty human femur diaphysis in a total of 120 measurements, while screws of different material (stainless steel and titanium alloy) and different design (locking and cortex screw) were inserted in three different screwing modes (manual vs. machine screwing at full and reduced rotational speed) with 6 thermocouples (3 cis and 3 trans cortex). Each was placed at a depth of 2 mm with a distance of 1.5 mm from the outer surface of the screw. RESULTS: The screw design (cortical > locking), the site of measurement (trans-cortex > cis-cortex) and the type of screw insertion (hand insertion > machine insertion) have an influence on the increase in bone temperature. The screw material (steel > titanium), the site of measurement (trans-cortex > cis-cortex) and the type of screw insertion (machine insertion > hand insertion) have an influence on the time needed to cool below critical temperature values. The combination of the two parameters (maximum temperature and cooling time), which is particularly critical for osteonecrosis, is found only at the trans-cortex. CONCLUSION: Inserting a screw hast the potential to increase the temperature of the surrounding bone tissue above critical values and therefore can induce osteonecrosis. The trans-cortex is the critical area for the development of temperatures above the osteonecrosis threshold, making effective cooling by irrigation difficult. It would be conceivable to cool the borehole with cold saline solution before inserting the screw or to cool the screw in cold saline solution. If possible, insertion by hand should be considered.

Revision with Locking Compression Plate by Compression Technique for Diaphyseal Nonunions of the Femur and the Tibia: A Retrospective Study of 54 Cases.

Nonunion after diaphyseal fracture of the femur or the tibia is a common but difficult complication for treatment. Currently, the main treatment modalities include nail dynamization, exchange nailing, and bone transport, but revision with compression plating in these nonunions was rarely reported. To evaluate the outcomes of compression plating in the treatment of femur and tibia shaft nonunions, we retrospectively reviewed 54 patients with diaphyseal nonunion of the tibia or the femur treated with locking compression plate (LCP) by compression technique. There were 46 aseptic and 8 septic nonunions in the case series. Patient's history, fracture characteristics, previous interventions, and types of nonunion were recorded. The possible reason which might lead to nonunion was also analyzed for each case. Patients with aseptic nonunions were revised by hardware removal and compression plating with or without bone grafting. For septic nonunions, a two-stage surgery strategy was used. Compression plating with iliac crest bone grafting (ICBG) or free vascularized fibular grafting (FVFG) was used as the final treatment for septic nonunions. The compression technique and bone grafting method were individualized in each case according to the patient's history and architecture of the nonunion. Each patient finished at least a two-year follow-up, and all cases achieved healing uneventfully. Our study showed that compression plating with LCP was an effective method to treat diaphyseal nonunions of the tibia and the femur. It is compatible with different bone grafting methods for both infected and noninfected nonunions and is a good alternative to the current treatment methods for these nonunions.

Can fracture healing be accelerated by serum transfer in head trauma cases? An experimental head trauma model in rats.

OBJECTIVES: In this study, we aimed to investigate whether the positive union effect caused by head trauma could be transferred between individuals. MATERIALS AND METHODS: Seventy-two male rats with an average weight of 375 g were used in this study and divided into four groups including 18 in each group. Group 1 consisted of serum donor rats that were exposed to head trauma, while Group 2 consisted of study rats with long bone fractures that were given the serum obtained from the rats in Group 1, Group 3 included control rats with isolated long bone fractures, and Group 4 included control rats with both head trauma and long bone fractures. For radiological evaluation, the ratio of the width of the callus to the width of the neighboring diaphysis was considered as the callus-to-diaphyseal ratio in the study and control groups. Histopathological and radiological evaluations was made on Days 10, 20, and 30. RESULTS: In evaluation of the radiological data regarding the callus-to-diaphyseal ratio, Group 3 was found to have significantly lower radiological values than Group 4 on Day 10 (p=0.006). Group 2 had significantly higher values than Group 3 (p=0.02). On Day 20, Group 2 exhibited significantly higher radiological values than Group 3 (p=0.004), but lower than Group 4 (p=0.032). As for Day 30, Group 2 exhibited significantly higher radiological values than Group 3, but lower than Group 4 (p=0.001). In the evaluation of the Huo scores obtained for histopathological evaluation, there was no significant difference among the groups on Days 10, 20, and 30 (p=0.295, p=0.569, and p=0.729, respectively). CONCLUSION: Our study results suggest that the osteoinductive effect after head trauma can be transmitted between individuals by means of serum transfer.