Patient-Reported Outcome Measurement Information Systems Physical Function and Pain Interference Scores Are Correlated With Tibial Shaft Fracture Nonunion Following Intramedullary Nailing

OBJECTIVES

To assess trends in Patient-Reported Outcome Measurement Information Systems (PROMIS) Physical Function (PF) and Pain Interference (PI) in surgically treated tibial shaft fracture patients progressing to union versus nonunion.

METHODS

DESIGN

Retrospective cohort study.

SETTING

Level 1 trauma center.

PATIENT SELECTION CRITERIA

Patients with operatively treated tibial shaft fractures (AO/OTA 42-A, B, C) using an intramedullary nail.

OUTCOME MEASURES AND COMPARISONS

PROMIS PF and PI were compared between patients progressing to union and patients requiring nonunion repair.

RESULTS

A total of 234 patients (196 union, 38 nonunion) were included consisting 144 men and 90 women. The mean age of included patients was 40.8 years. A significant difference in mean PROMIS PF between union and nonunion patients was observed at 1-3 months ( P = 0.005), 3-6 months ( P < 0.001), 6-9 months ( P = 0.003), and 6-12 months ( P = 0.018). The odds of developing nonunion for every unit decrease in PROMIS PF was significant at 3-6 months (OR 1.07, P = 0.028) and 6-9 months (OR 1.17, P = 0.015). A significant difference in mean PROMIS PI between union and nonunion patients was observed at 1-3 months ( P = 0.001), 3-6 months ( P = 0.005), and 6-9 months ( P = 0.005). The odds of developing nonunion for every unit increase in PROMIS PI was significant at 1-3 months (OR 1.11, P = 0.005), 3-6 months (OR 1.10, P = 0.011), and 6-9 months (OR 1.23, P = 0.011).

CONCLUSIONS

Poorly trending PROMIS PF and PI in the clinical setting is a factor that can be used to evaluate progression to nonunion following tibial shaft repair where imaging studies may lag behind.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Achieving Bone Healing Non-Operatively in Humeral Fractures in Two Patients with Risk Factors for Nonunion Utilizing a Specialized Orthosis

We report the treatment of two patient with humeral fractures with one or more risk factors for nonunion. The first patient was elderly with a previously diagnosed central nervous sys-tem injury. The second elderly patient previously sustained a cerebral vascular accident affecting the fractured arm. The fracture was oblique in the proximal third of the humerus. We achieved bone healing non-operatively utilizing a spe-cialized plastic orthosis that included a deforming element made of dense foam. This device asymmetrically increases the soft tissue pressure around the fracture.

Cytotoxicity of novel hybrid composite materials for making bone fracture plates

Bone fracture plates are usually made from steel or titanium, which are much stiffer than cortical bone. This may cause bone 'stress shielding' (i.e. bone resorption leading to plate loosening) and delayed fracture healing (i.e. fracture motion is less than needed to stimulate callus formation at the fracture). Thus, the authors previously designed, fabricated, and mechanically tested novel 'hybrid' composites made from inorganic and organic materials as potential bone fracture plates that are more flexible to reduce these negative effects. This is the first study to measure the cytotoxicity of these composites via the survival of rat cells. Cubes of carbon fiber/flax fiber/epoxy and glass fiber/flax fiber/epoxy had better cell survival vs. Kevlar fiber/flax fiber/epoxy (57% and 58% vs. 50%). Layers and powders made of carbon fiber/epoxy and glass fiber/epoxy had higher cell survival than Kevlar fiber/epoxy (96%-100% and 100% vs. 39%-90%). The presence of flax fibers usually decreased cell survival. Thus, carbon and glass fiber composites (with or without flax fibers), but not Kevlar fiber composites (with or without flax fibers), may potentially be used for bone fracture plates.

In vivo axial load-share ratio measurement using a novel hexapod system for safe external fixator removal

BACKGROUND

External fixation is widely used in the treatment of traumatic fractures; however, orthopedic surgeons encounter challenges in deciding the optimal time for fixator removal. The axial load-share ratio (LS) of the fixator is a quantitative index to evaluate the stiffness of callus healing. This paper introduces an innovative method for measuring the LS and assesses the method's feasibility and efficacy. Based on a novel hexapod LS-measurement system, the proposed method is to improve the convenience and precision of measuring LS in vivo, hence facilitating the safe removal of external fixators.

METHODS

A novel hexapod system is introduced, including its composition, theoretical model, and method for LS measurement. We conducted a retrospective study on 82 patients with tibial fractures treated by the Taylor Spatial Frame in our hospital from September 2018 to June 2020, of which 35 took LS measurements with our novel method (Group I), and 47 were with the traditional method (Group II). The external fixator was removed when the measurement outcome (LS < 10%) was consistent with the surgeon's diagnosis based on the clinical and radiological assessment (bone union achieved).

RESULTS

No significant difference was found in the fracture healing time (mean 25.3 weeks vs. 24.9 weeks, P > 0.05), frame-wearing duration (mean 25.5 weeks vs. 25.8 weeks, P > 0.05), or LS measurement frequency (mean 1.1 times vs. 1.2 times, P > 0.05). The measurement system installation time in Group I was significantly shorter compared to Group II (mean 14.8 min vs. 81.3 min, P < 0.001). The LS value of the first measurement in Group I was lower than that of Group II (mean 5.1% vs. 6.9%, P = 0.011). In Group I, the refracture rate was 0, but in Group II it was 4.3% (2/47, P > 0.05).

CONCLUSION

The novel hexapod LS-measurement system and involved method demonstrated enhanced convenience and precision in measuring the LS of the external fixator in vivo. The LS measurement indicates the callus stiffness of fracture healing, and is applicable to evaluate the safety of removing the fixator. Consequently, it is highly recommended for widespread adoption in clinical practice.

A review of 10 patients treated with the masquelet technique and microsurgical technique combined for Gustilo type III open tibial fractures

BACKGROUND

Open tibial fractures often include severe bone loss and soft tissue defects and requires complex reconstructive operations. However, the optimal treatment is unclear.

METHODS

This retrospective study enrolled patients with Gustilo type III open tibial fractures from January 2018 to January 2021 to assess the clinical utility of Masquelet technique together with microsurgical technique as a combined strategy for the treatment of open tibial fractures. The demographics and clinical outcomes including bone union time, infection, nonunion and other complications were recorded for analysis. The bone recovery quality was evaluated by the AOFAS Ankle-Hindfoot Scale score and the Paley criteria.

RESULTS

We enrolled 10 patients, the mean age of the patients and length of bone defects were 31.7 years (range, 23-45 years) and 7.5 cm (range, 4.5-10 cm) respectively. Bone union was achieved for all patients, with an average healing time of 12.2 months (range, 11-16 months). Seven patients exhibited a bone healing time of less than 12 months, whereas 3 patients exhibited a bone healing time exceeding 12 months. No significant correlation was found between the length of bone loss and healing time. In addition, no deep infection or nonunion was observed, although 2 patients experienced wound fat liquefaction with exudates and 1 patient presented with a bloated skin flap. The average AOFAS Ankle-Hindfoot Scale score was 80.5 (range, 74-85), and all patients were evaluated as good or exellent based on the Paley criteria.

CONCLUSIONS

Our study indicated that the use of the Masquelet technique and the microsurgical technique as a combined strategy is safe and effective for the treatment of Gustilo type III open tibial fractures.

Study on the therapeutic effect of Kirschner wire tension band combined with anchor cross-stitch technique in the treatment of comminuted patellar inferopolar fractures

PURPOSES

Fractures of the inferior patellar pole, unlike other patellar fractures, present challenges for traditional surgical fixation methods. This article introduces the clinical technique and outcomes of using Kirschner wire tension band combined with anchor screw cross-stitch fixation for comminuted inferior patellar pole fractures.

METHODS

This retrospective case series study included 14 patients with comminuted inferior patellar pole fractures treated at our institution from September 1, 2020, to April 30, 2022. All patients underwent surgery using the Kirschner wire tension band with anchor screw cross-stitch technique. Follow-up assessments involved postoperative X-rays to evaluate fracture healing, as well as clinical parameters such as healing time, Visual Analog Scale (VAS) scores, range of motion (ROM), and Bostman scores.

RESULTS

All patients were followed for an average of over 12 months, with no cases of internal fixation failure. Knee joint stability and function were excellent. X-rays revealed an average healing time of approximately 10.79 ± 1.53 weeks, hospitalization lasted 5.64 ± 1.15 days, surgery took approximately 37.86 ± 5.32 minutes, and intraoperative blood loss was 33.29 ± 8.15 ml. One patient experienced irritation from the internal fixation material. At the final follow-up, the Bostman score averaged 28.29 ± 0.83, knee joint flexion reached 131.07° ± 4.88°, all patients achieved full knee extension, and the VAS score was 0.36 ± 0.63.

CONCLUSION

Kirschner wire tension band with anchor screw cross-stitch fixation for comminuted inferior patellar pole fractures delivered satisfactory clinical outcomes. This surgical method, characterized by its simplicity and reliability, is a valuable addition to clinical practice.

Knockout of formyl peptide receptor 1 reduces osteogenesis and bone healing

AIMS

Formyl peptide receptor 1 (FPR1), from a G-protein coupled receptor family, was previously well-characterized in immune cells. But the function of FPR1 in osteogenesis and fracture healing was rarely reported. This study, using the FPR1 knockout (KO) mouse, is one of the first studies that try to investigate FPR1 function to osteogenic differentiation of bone marrow-derived stem cells (BMSCs) in vitro and bone fracture healing in vivo.

MATERIALS AND METHODS

Primary BMSCs were isolated from both FPR1 KO and wild type (WT) mice. Cloned mouse BMSCs (D1 cells) were used to examine role of FoxO1 in FPR1 regulation of osteogenesis. A closed, transverse fracture at the femoral midshaft was created to compare bone healing between KO and WT mice. Biomechanical and structural properties of femur were compared between healthy WT and KO mice.

KEY FINDINGS

FPR1 expression increased significantly during osteogenesis of both primary and cloned BMSCs. Compared to BMSCs from FPR1 KO mice, WT BMSCs displayed considerably higher levels of osteogenic markers as well as mineralization. Osteogenesis by D1 cells was inhibited by either an FPR1 antagonist cFLFLF or a specific inhibitor of FoxO1, AS1842856. In addition, the femur from WT mice had better biomechanical properties than FPR1 KO mice. Furthermore, bone healing in WT mice was remarkably improved compared to FPR1 KO mice analyzed by X-ray and micro-CT.

SIGNIFICANCE

These findings indicated that FPR1 played a vital role in osteogenic differentiation and regenerative capacity of fractured bone, probably through the activation of FoxO1 related signaling pathways.

How successful is synthetic graft treatment for children with pathological hip fractures?

PURPOSE

To determine whether synthetic grafts are a satisfactory treatment option for pathological proximal femoral fractures in children.

METHODS

Paediatric patients treated for pathological fractures of the proximal femur between 2013 and 2020 were evaluated retrospectively. 17 patients with a mean age of 10.7 years (range 6-16 years) were assessed. The definitive histopathological diagnoses were SBC (simple bone cyst) (12) and ABC (aneurysmal bone cyst) (5). The median duration of follow-up was 37 months (range 12-70 months).

RESULTS

All patients returned to their normal daily routine within 3-8 months following surgery. The mean post-op recovery time was 3.2 months (range 3-6 months). Graft was incorporated at approximately 12 months. No significant radiographic healing was observed in 2 patients. In the remaining 15 patients, the mean duration of healing was 14 months (range 8-24 months).

CONCLUSION

Synthetic grafts are a satisfactory treatment option for pathological proximal femoral fractures in children.

A Comparative Analysis of Between Percutaneous Cannulated Screw Fixation and Traditional Plate Internal Fixation in Treatment of Sanders II and III Calcaneal Fractures

The objective of this study is to compare the clinical efficacy of percutaneous cannulated screw fixation and traditional plate internal fixation in the treatment of Sanders II and III calcaneal fractures. The records of 64 patients were retrospectively analyzed. Thirty-three cases were fixed by percutaneous cannulated screws. Thirty-one cases were fixed with traditional steel plates. The preoperative preparation time of the screw group and plate group was 3 ± 1.7 days and 4.6 ± 2.1 days. The surgery time was 118.9 ± 43.8 minutes and 146.9 ± 47.6 minutes. The length of hospitalization was 8.7 ± 3.9 days and 17.0 ± 7.9 days. Intraoperative blood loss was 38.2 ± 27.7 mL and 67.1 ± 58.8 mL. The postoperative drainage volume of the plate group was 85.1 ± 53.7 mL, and no wound drainage was needed in the screw group after surgery. Postoperative wound complications occurred in 2 cases of the screw group and 8 cases of the plate group. The recovery effects of Gissane angle and Bohler angle are similar in the 2 groups. The excellent and good rate of the American Orthopaedic Foot and Ankle Society ankle-hindfoot Scale in the screw group was 96.8% at 12 months after surgery, whereas the rate was 93.5% in the plate group. Compared with the traditional plate internal fixation, the percutaneous cannulated screw group achieved a similar excellent and good rate of clinical treatment. It has the advantages of less trauma, less bleeding, low incidence of complications, short preoperative preparation, and hospitalization time.

Does the Level and Complexity of Femur Fracture Determine Intramedullary Peak Pressures During Reamed Femoral Nailing? A Prospective Study

OBJECTIVES

To investigate femoral intramedullary (IM) pressures during reamed antegrade nailing and to determine whether fracture level and/or complexity affect peak pressures.

METHODS

DESIGN

Prospective, nonrandomized observational cohort.

SETTING

Single level I trauma center.

PATIENT SELECTION CRITERIA

Patients presenting with femur fractures (OTA/AO 31A3; 32A; 32B; 32C; 33A2; 33A3), requiring antegrade IM nail fixation, were included in this study. Excluded were minors and patients presenting with hemodynamic instability, a reduced level of consciousness and intoxication. Femurs were divided into thirds based on preoperative radiological measurements and allocated to 3 groups based on fracture location: Proximal (A), middle (B), and distal (C) third femur fractures. Fracture complexity was also documented.

OUTCOME MEASURES AND COMPARISONS

Peak IM pressures of proximal, middle, and distal third femoral fractures were compared during antegrade femoral IM nail fixation.

RESULTS

Twenty-two fractures in 21 patients were enrolled and treated over a 4-month period with a distribution of fracture locations of group A = 12, group B = 6, and group C = 4. Measured mean resting distal IM pressures were significantly higher ( P < 0.05) in proximal fractures (group A: 52.5 mm Hg) than in middle and distal third fractures (group B: 36.6 mm Hg and group C: 27.5 mm Hg). Greatest peak pressures were generated during the first ream in groups A and B, occurring distal to the fracture in all cases. Group A averaged 363.8 mm Hg (300-420), group B 174.2 mm Hg (160-200), and group C 98.8 mm Hg (90-100). There was a significant difference comparing group A with B and C combined ( P < 0.01) and group A with B ( P < 0.05) and C ( P < 0.05]) individually. Group A consisted of 6 comminuted and 6 simple fracture configurations. Mean peak pressures in these subgroups differed significantly: 329 mm Hg (300-370) versus 398 mm Hg (370-430), respectively ( P < 0.05). Complex fractures in study groups B and C did not have significantly different peak pressures compared with simple fractures ( P > 0.05).

CONCLUSIONS

Both the fracture location and comminution affect peak IM pressures during reamed antegrade femoral nailing. Proximal, simple fracture configurations resulted in significantly higher pressures when compared with more distal and comminuted fracture configurations.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Litsea glutinosa extract promotes fracture healing and prevents bone loss via BMP2/SMAD1 signaling

Estrogen deficiency is one of the main causes for postmenopausal osteoporosis. Current osteoporotic therapies are of high cost and associated with serious side effects. So there is an urgent need for cost-effective anti-osteoporotic agents. Anti-osteoporotic activity of Litsea glutinosa extract (LGE) is less explored. Moreover, its role in fracture healing and mechanism of action is still unknown. In the present study we explore the osteoprotective potential of LGE in osteoblast cells and fractured and ovariectomized (Ovx) mice models. Alkaline phosphatase (ALP), MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and mineralization assays revealed that LGE treatment increased osteoblast cell differentiation, viability and mineralization. LGE treatment at 0.01 μg increased the expression of BMP2, PSMAD, RUNX2 and type 1 col. LGE also mitigated RANKL-induced osteoclastogenesis. Next, drill hole injury Balb/C mice model was treated with LGE for 12 days. Micro-CT analysis and Calcein labeling at the fracture site showed that LGE (20 mg/kg) enhanced new bone formation and bone regeneration, also increased expression of BMP2/SMAD1 signaling genes at fracture site. Ovx mice were treated with LGE for 1 month. μCT analysis indicated that the treatment of LGE at 20 mg/kg dose prevented the alteration in bone microarchitecture and maintained bone mineral density and bone mineral content. Treatment also increased bone strength and restored the bone turnover markers. Furthermore, in bone samples, LGE increased osteogenesis by enhancing the expression of BMP2/SMAD1 signaling components and decreased osteoclast number and surface. We conclude that LGE promotes osteogenesis via modulating the BMP2/SMAD1 signaling pathway. The study advocates the therapeutic potential of LGE in osteoporosis treatment.

Homeopathic Ankle Dislocation for Treatment of Unstable Trimalleolar Fractures Involving Posterior Die-Punch Fragment: A Retrospective Cohort Study

OBJECTIVES

Unstable trimalleolar fractures are relatively complex and more difficult to manage if die-punch fracture is present. We aimed to evaluate the curative effect of homeopathic ankle dislocation on the unstable trimalleolar fractures involving posterior die-punch fragments.

METHODS

A total of 124 patients diagnosed with unstable trimalleolar fractures combined with post-die punch fragment between June 2008 and June 2020 were retrospectively included. Patients who received homeopathic ankle dislocation were named as the experimental group, and patients who accepted conventional treatment were control group. The fracture healing time, wound healing, American Orthopedic Foot and Ankle Society ankle-hindfoot scale (AOFAS), visual analogue scale (VAS), the Kellgren-Lawrence arthritis grading scale (KLAGS) and short-form 36 score (SF-36) scores were collected. Student t-test was used for fracture healing time. Wound healing and SF-36 were compared using the Mann-Whitney test. Repeated measurement analysis of variance (ANOVA) was used for AOFAS and VAS. χ2-test was used for KLAGS.

RESULTS

AOFAS showed statistically significant differences between the two groups (p = 0.001). In non-weight-bearing and weight-bearing conditions, VAS scores were significant different between the two groups, and there was an interaction between group and time point (p < 0.001). The experimental group was superior to the control group in terms of physical function (p = 0.022), role-physical (p = 0.018), general health (p = 0.001) and social function (p = 0.042).The operation time of experimental group was shorter than that of control group (p < 0.001).

CONCLUSION

Homeopathic ankle dislocation is used for the unstable trimalleolar fractures involving posterior die-punch fragment, which can provide better functional outcomes while shortening the operation time and recovery period.

The comparison of functional bracing of humeral shaft fractures: thermoplastic custom against preprepared commercial braces

BACKGROUND

Functional humeral bracing of midshaft humeral fractures has been widely accepted as a gold standard for nonoperative treatment. Despite reported high union rates, there is no proven superiority of any orthosis. Here we aim to compare the outcomes after the use of custom-made thermoplastic vs. commercial humeral brace with regard to time to union, nonunion rates, types of nonunion, and conversion to surgery.

METHODS

Patients with humeral fractures treated between 2018 and 2021 were identified retrospectively by electronic records. Only diaphyseal humerus fractures (AO 12) were included in the study. Proximal (AO 11) or distal (AO 13) fractures, open fractures, pathologic fractures, bilateral fractures, multiple fractures, and patients lost to follow-up were excluded. Patients attending one center received a custom-made thermoplastic splint, whereas those at the other center had an off-the-shelf humeral brace applied. Radiologic union was defined as healing of at least 3 of 4 cortices determined from follow-up radiographs. Data calculations were performed using the χ2 test.

RESULTS

A total of 53 patients treated with a thermoplastic brace and 43 with a commercial brace were identified. A total of 52 men were included, and the cohort's mean age was 60.1 years (standard deviation: 16.1 years). Both groups had similar gender and age distributions. More patients achieved union with a thermoplastic brace (79.2%) than those with a commercial brace (76.7%), which was statistically significant (χ2, P = .04). Although time to union was similar both clinically and radiologically, patients with a commercial brace converted to surgical treatment more frequently (11 vs. 14 cases).

CONCLUSION

Thermoplastic custom-made braces provide better fracture stability, allowing for statistically significantly higher rates of fracture union during a similar treatment period to commercially available splints. Patients wearing a commercial splint were significantly more likely to develop hypertrophic nonunion requiring surgery.

Advances in Hand Therapy: Best Practice in Conservative Management of Proximal Phalangeal Fractures in Children

BACKGROUND

Proximal phalangeal fractures are one of the most commonly treated hand injuries in children. Conservative management of these fractures is often to splint for 5 weeks post injury, despite children presenting as clinically healed at 3 weeks post injury. Therefore, we investigated the effect of splinting for only 3 weeks in children who present with clinically healed proximal phalangeal fractures at 3 weeks compared with usual care.

METHODS

Participants (n=80, aged 10.3 ±2.5 years) presenting to the Hand Clinic of a tertiary Children's Hospital in Sydney, Australia, were randomly allocated into a Current Protocol and a New Protocol group. Following were the inclusion criteria: aged between 5 and 16 years; present with an non-displaced or minimally displaced and stable fracture; no surgical intervention; assessed as clinically healed at 3-week visit. The primary outcome measure was total active motion (TAM) of the injured digit compared with the contralateral digit (deg), at 5 weeks post injury. Secondary outcome measures were grip strength, and a parent-reported questionnaire. Statistical analysis used χ 2 test and the absolute difference described by a 90% CI. The New Protocol was considered noninferior if the 90% CI overlap was > 20% of the Current Protocol. Analysis was by intention to treat.

RESULTS

There was a 10% loss to follow up at 5 weeks (Current Protocol =4, New Protocol =4). All CIs between groups overlapped by >10%. TAM 90% CI for Current Protocol was 17.7 to 5.4 degrees and for the New Protocol was 4.7 to 1.6 degrees.

CONCLUSIONS

A change in practice is warranted to cease immobilization for children with conservatively managed proximal phalangeal fractures who present as clinically healed at 3 weeks. Therapist assessment of fracture healing is an appropriate indicator for intervention and can be utilized in a therapist-led model of care.

LEVEL OF EVIDENCE

Level 1-noninferiority randomized control trial with 2 parallel arms.

Polytherapy versus monotherapy in the treatment of tibial non-unions: a retrospective study

BACKGROUND

Treating tibial non-unions efficiently presents a challenge for orthopaedic trauma surgeons. The established gold standard involves implanting autologous bone graft with adequate fixation, but the addition of biologicals according to the so-called diamond concept has become increasingly popular in the treatment of non-unions. Previous studies have indicated that polytherapy, which involves implanting mesenchymal stem cells, bioactive factors and osteoconductive scaffolds, can improve bone healing. This study aims to evaluate the efficacy of polytherapy compared with monotherapy in treating tibial non-unions of varying severity.

MATERIALS AND METHODS

Data from consecutive tibial non-unions treated between November 2014 and July 2023 were retrospectively analysed. The Non Union Scoring System (NUSS) score before non-union surgery, and the Radiographic Union Score for Tibial fractures (RUST), scored at 1, 3, 6, 9, 12 and 18 months post-surgery, were recorded. Initially, a comparison was made between the polytherapy and monotherapy groups. Subsequently, patients receiving additional surgical non-union treatment were documented, and the frequency of these treatments was tallied for a subsequent per-treatment analysis.

RESULTS

A total of 34 patients were included and divided into a polytherapy group (n = 15) and a monotherapy group (n = 19). The polytherapy group demonstrated a higher NUSS score (44 (39, 52) versus 32 (29, 43), P = 0.019, z = -2.347) and a tendency towards a higher success rate (93% versus 68%, P = 0.104) compared with the monotherapy group. For the per-treatment analysis, 44 treatments were divided into the polytherapy per-treatment group (n = 20) and the monotherapy per-treatment group (n = 24). The polytherapy per-treatment group exhibited a higher NUSS score (48 (43, 60) versus 38 (30, 50), P = 0.030, z = -2.173) and a higher success rate (95% versus 58%, P = 0.006) than the monotherapy per-treatment group. Within the monotherapy per-treatment group, the NUSS score displayed excellent predictive performance (AUC = 0.9143). Setting the threshold value at 48, the sensitivity and specificity were 100.0% and 70.0%, respectively.

CONCLUSIONS

Polytherapy is more effective than monotherapy for severe tibial non-unions, offering a higher success ratio. The NUSS score supports decision-making in treating tibial non-unions.

LEVEL OF EVIDENCE

Level III.

Fracture healing on non-union fracture model promoted by non-thermal atmospheric-pressure plasma

Non-thermal atmospheric-pressure plasma (NTAPP) is attracting widespread interest for use in medical applications. The tissue repair capacity of NTAPP has been reported in various fields; however, little is known about its effect on fracture healing. Non-union or delayed union after a fracture is a clinical challenge. In this study, we aimed to investigate how NTAPP irradiation promotes fracture healing in a non-union fracture model and its underlying mechanism, in vitro and in vivo. For the in vivo study, we created normal and non-union fracture models in LEW/SsNSlc rats to investigate the effects of NTAPP. To create a fracture, a transverse osteotomy was performed in the middle of the femoral shaft. To induce the non-union fracture model, the periosteum surrounding the fracture site was cauterized after a normal fracture model was created. The normal fracture model showed no significant difference in bone healing between the control and NTAPP-treated groups. The non-union fracture model demonstrated that the NTAPP-treated group showed consistent improvement in fracture healing. Histological and biomechanical assessments confirmed the fracture healing. The in vitro study using pre-osteoblastic MC3T3-E1 cells demonstrated that NTAPP irradiation under specific conditions did not reduce cell proliferation but did enhance osteoblastic differentiation. Overall, these results suggest that NTAPP is a novel approach to the treatment of bone fractures.

[Treatment of irreducible intertrochanteric femoral fracture in elderly by folding top technique combined with right-angle pliers prying and pulling under G-arm X-ray fluoroscopy]

Objective

To explore the effectiveness of irreducible intertrochanteric femoral fracture in the elderly by treating with folding top technique and right-angle pliers prying and pulling under G-arm X-ray fluoroscopy.

Methods

The clinical data of 74 elderly patients with irreducible intertrochanteric femoral fracture admitted between February 2016 and December 2022 and met the selection criteria were retrospectively analyzed. Among them, 38 cases were treated with folding top technique combined with right-angle pliers prying and pulling under G-arm X-ray fluoroscopy and intramedullary nailing fixation (study group), and 36 cases were treated with limited open reduction combined with other reduction methods and intramedullary nailing fixation (control group). There was no significant difference in baseline data between the two groups, such as age, gender, cause of injury, affected side and classification of fractures, complicated medical diseases, and time from injury to operation ( P>0.05). The operation time, intraoperative blood loss, hospital stay, fracture reduction time, fracture healing time, and complications of the two groups were recorded and compared. The quality of fracture reduction was evaluated by Baumgaertner et al. and Chang et al. fracture reduction standards.

Results

Patients in both groups were followed up 10-14 months, with an average of 12 months. The operation time and intraoperative blood loss in the study group were significantly less than those in the control group ( P<0.05), there was no significant difference in hospital stay between the two groups ( P>0.05). At 2 days after operation, according to the fracture reduction standards of Baumgaertner et al. and CHANG Shimin et al., the quality of fracture reduction in the study group was better than that in the control group, and the fracture reduction time in the study group was shorter than that in the control group, with significant differences ( P<0.05). After operation, the fractures of the two groups all healed, and there was no significant difference in healing time between the two groups ( P>0.05). During the follow-up, there was no complication such as incision infection, internal fixation failure, deep venous thrombosis of lower limbs, intramedullary nail breakage, spiral blade cutting, or hip varus in the two groups, except for 2 cases of coxa vara in the control group.

Conclusion

For the irreducible intertrochanteric femoral fracture, using folding top technique combined with right-angle pliers prying and pulling under G-arm X-ray fluoroscopy can obviously shorten the operation time, reduce the intraoperative blood loss, and improve the quality of fracture reduction.

Radiographic outcomes and non-union factor analysis in fragmentary segmental femoral shaft fractures (AO/OTA 32C3) treated with reamed antegrade nailing

This study retrospectively assessed radiographic outcomes and risk factors associated with non-union in femoral shaft fragmentary segmental fractures (AO/OTA 32C3) treated with reamed antegrade intra-medullary nailing. Radiological outcomes, including union and alignment, were evaluated. The risk factors for non-union were investigated, including demographics and treatment-related characteristics, such as the number of interlocking screws, segmentation length, main third fragment length, distance of the main third fragment, width ratio and exposed nail length in one cortex from immediate post-operative radiographs. Multivariate logistic regression was used for statistical analysis. Among 2295 femoral shaft fracture patients from three level-1 trauma centers, 51 met the inclusion criteria. The radiological union was achieved in 37 patients (73%) with a mean union time of 10.7 ± 4.8 months. The acceptable axial alignment was observed in 30 patients (59%). Multiple logistic regression analysis identified only exposed nail length as a significant risk factor for non-union (odds ratio: 1.599, p = 0.003) and the cut-off value was 19.1 mm (sensitivity, 0.786; specificity, 0.811). The study revealed high rates of non-union (27%) and malalignment (41%). Therefore, patients who underwent intramedullary nailing with an exposed nail length greater than 19.1 mm or about twice the nail diameter should be cautioned of the potential non-union.

Tenascin-C promotes endochondral ossification and fracture healing through Hedgehog and Hippo signaling

Fractures are frequent and severe musculoskeletal injuries. This study aimed to investigate the function of tenascin-C (TNC) in regulating chondrogenic during fracture healing and elucidate the underlying molecular mechanisms. A well-established femur fracture model in male C57BL/6J mice was used to transect the middle diaphysis of the femur. To identify the essential role of TNC, shTNC lentiviruses or TNC protein were administered in the animal model. Micro-CT analysis, histologic analysis, immunostaining assays, and gene expression analysis were employed to investigate the effect of TNC during fracture healing. An in vitro mesenchymal stem cell culture system was developed to investigate the role and molecular mechanism of TNC in regulating chondrogenesis. TNC expression was induced at the inflammatory phase and peaked at the cartilaginous callus phase during fracture healing. Knockdown of TNC expression in callus results in decreased callus formation and impaired fracture healing. Conversely, administration of exogenous TNC promoted chondrogenic differentiation, cartilage template formation and ultimately improved fracture healing. Both the Hedgehog and Hippo signaling pathways were found to be involved in the pro-chondrogenic function of TNC. Our observations demonstrate that TNC is a crucial factor responsible for endochondral ossification in fracture healing and provide a potential therapeutic strategy for promoting fracture healing.

Is there a role for N1-N2 neutrophil phenotypes in bone regeneration? A systematic review

PURPOSE

This review aims to provide an overview of the multiple functions of neutrophils, with the recognition of the inflammatory (N1) and regenerative (N2) phenotypes, in relation to fracture healing.

METHODS

A literature search was performed using the PubMed database. The quality of the articles was evaluated using critical appraisal checklists.

RESULTS

Thirty one studies were included in this review. These studies consistently support that neutrophils exert both beneficial and detrimental effects on bone regeneration, influenced by Tumor Necrosis Factor-α (TNF-α), Interleukin 8 (IL-8), mast cells, and macrophages. The N2 phenotype has recently emerged as one promoter of bone healing. The N1 phenotype has progressively been connected with inflammatory neutrophils during fracture healing.

CONCLUSIONS

This review has pinpointed various aspects and mechanisms of neutrophil influence on bone healing. The recognition of N1 and N2 neutrophil phenotypes potentially shed new light on the dynamic shifts taking place within the Fracture Hematoma (FH).

The effect of valgus reduction on resistant subtrochanteric femoral non-unions: a single-centre report of twenty six cases

PURPOSE

Re-revision of subtrochanteric non-unions is technically challenging and lacks robust evidence. The results of managing subtrochanteric fractures after multiple failed procedures have rarely been reported in the literature. This study aims to evaluate the effect of valgus reduction on non-united subtrochanteric fractures with single or multiple failed revision surgeries.

METHODS

Twenty-six patients with aseptic subtrochanteric fracture non-union underwent failed single or multiple revision procedures after index fracture fixation surgery between 2011 and 2019. The exclusion criteria were as follows: septic non-union, peri-prosthetic, and pathological fractures. Lateral-based wedge valgus reduction and compression at the non-union site using a valgus-contoured DCS together with decortication, debridement, and bone grafting were used. The main outcome measurement was radiological union, pain, LLD, HHS, and restoration of pre-fracture activities.

RESULTS

The mean follow-up was 4.5 years (range 3 to 7); prior revision surgeries range from two to five and union at 6.5 months (range 3 to 10) and the delayed union in one case and an infected non-union in one case. The mean LLD was 4 cm (range 3 to 5), which improved to 1.5 cm (range 1 to 4) (P-value < 0.001). The mean VAS was 7 (range 6 to 8), and 24 patients achieved painless ambulation without a walking aid after the union. The mean HHS was 40 (range 25 to 65), which improved to 85 (range 55 to 95) (P-value < 001), achieving 15 excellent, ten good, and one poor results.

CONCLUSION

Mechanical optimisation by lateral closing wedge and stable fixation with pre-contoured DCS with biological enhancement resulted in a successful outcome in recalcitrant subtrochanteric non-unions.

Biomechanical Effects of Mechanical Stress on Cells Involved in Fracture Healing

Fracture healing is a complex staged repair process in which the mechanical environment plays a key role. Bone tissue is very sensitive to mechanical stress stimuli, and the literature suggests that appropriate stress can promote fracture healing by altering cellular function. However, fracture healing is a coupled process involving multiple cell types that balance and limit each other to ensure proper fracture healing. The main cells that function during different stages of fracture healing are different, and the types and molecular mechanisms of stress required are also different. Most previous studies have used a single mechanical stimulus on individual mechanosensitive cells, and there is no relatively uniform standard for the size and frequency of the mechanical stress. Analyzing the mechanisms underlying the effects of mechanical stimulation on the metabolic regulation of signaling pathways in cells such as in bone marrow mesenchymal stem cells (BMSCs), osteoblasts, chondrocytes, and osteoclasts is currently a challenging research hotspot. Grasping how stress affects the function of different cells at the molecular biology level can contribute to the refined management of fracture healing. Therefore, in this review, we summarize the relevant literature and describe the effects of mechanical stress on cells associated with fracture healing, and their possible signaling pathways, for the treatment of fractures and the further development of regenerative medicine.

External fixator versus Ilizarov external fixator for pediatric tibial shaft fractures: A retrospective comparative study

INTRODUCTION

External fixators (EF) are widely employed for pediatric tibial shaft fractures, being a prevalent choice in clinical practice. However, they are associated with numerous complications, such as loss of reduction, delayed union, and nonunion. An alternative approach involves the use of Ilizarov external fixators (IEF), which have been documented in the treatment of tibial shaft fractures in various studies. This study endeavors to retrospectively compare the clinical outcomes of EF and IEF in the treatment of pediatric tibial shaft fractures.

METHODS

The study retrospectively examined patients aged 5-14 years who underwent treatment for tibial shaft fractures at our institute between January 2017 and January 2023. These individuals were subsequently classified into EF and IEF groups. Exclusions comprised patients presenting with pathological fracture, neuromuscular disorder, metabolic disease, prior tibial fracture or instrumentation, and polytrauma. Additionally, individuals with a follow-up duration of more than 12 months or incomplete medical records were excluded.

RESULTS

A total of 45 patients were divided into two groups: the EF group, comprising 24 patients (18 males, 6 females), and the IEF group, consisting of 21 patients (17 males, 4 females). The two groups exhibited no statistically significant differences in terms of sex, age, body weight, time from injury to surgery, AO classification, or concomitant injuries. There were two cases of nonunion in the EF group. Radiological union occurred more rapidly in the IEF group (7.8 ± 0.4 weeks) than in the EF group (9.3 ± 1.1 weeks) (P < 0.05). The mean hospitalization duration differed significantly between the EF group (6.7 ± 3.4 days) and the IEF group (7.5 ± 1.1 days) (P > 0.05). The mean duration of the operative procedure significantly differed between the IEF group (147.8 ± 24.5 min) and the EF group (77.2 ± 43.9 min) (P < 0.001). A significant difference (P < 0.001) in weight-bearing time was observed between the IEF group (2.6 ± 0.7 weeks) and the EF group (9.9 ± 1.4 weeks). According to the Johner-Wruhs criteria, no significant differences were found between the two groups. A significant difference (P < 0.001) in hospitalization costs was observed between the IEF group (7848.0 ± 262.4 $) and the EF group (5403.0 ± 233.3 $).

CONCLUSION

EF is cheaper, quicker and simpler and we need more randomized controlled studies and that this is a pilot study only. Both types of surgery are good choices for children. Nevertheless, the IEF group demonstrates advantages such as early weight-bearing capability and faster fracture healing.

Sildenafil delays bone remodeling of fractured femora in aged mice by reducing the number and activity of osteoclasts within the callus tissue

The elderly exhibit a reduced healing capacity after fracture, which is often associated with delayed or failed bone healing. This is due to a plethora of factors, such as an impaired bone vascular system and delayed angiogenesis. The phosphodiesterase-5 (PDE-5) inhibitor sildenafil exerts pro-angiogenic and pro-osteogenic effects. Hence, we herein investigated in aged mice whether sildenafil can improve fracture healing. For this purpose, 40 aged CD-1 mice (16-18 months) were daily treated with 5 mg/kg body weight sildenafil (n = 20) or vehicle (control, n = 20) by oral gavage. The callus tissue of their femora was analyzed at 2 and 5 weeks after fracture by X-ray, biomechanics, micro-computed tomography (µCT), histology, immunohistochemistry as well as Western blotting. These analyses revealed a significantly increased bone volume and higher ratio of callus to femoral bone diameter in sildenafil-treated mice at 5 weeks after fracture when compared to controls. This was associated with a reduced number and activity of osteoclasts at 2 weeks after fracture, most likely caused by an increased expression of osteoprotegerin (OPG). Taken together, these findings indicate that sildenafil does not improve fracture healing in the elderly but delays the process of bone remodeling most likely by reducing the number and activity of osteoclasts within the callus tissue.

Fracture gap and working length are important actionable factors affecting bone union after minimally invasive plate osteosynthesis for the treatment of simple diaphyseal or distal metaphyseal tibia fractures

INTRODUCTION

Indirect reduction of minimally invasive plate osteosynthesis (MIPO) can often result in delayed union in tibia fractures. This study evaluated several factors in MIPO in relation to bone union.

HYPOTHESIS

We hypothesized that the fracture gap, plate - tibia distance, or working length would have a substantial effect on the tibia union rate.

MATERIALS AND METHODS

Forty-one patients with simple diaphyseal or distal metaphyseal tibia fractures who underwent internal fixation surgery using the MIPO technique were divided into two groups: patients with delayed union and patients without delayed union. Non-actionable factors involving AO/OTA classification, fibula fracture and actionable factors including postoperative fracture gap, plate - tibia distance, working length in relation to parameters of bone union were compared between the two groups. Also cumulative rates of bone union and risk factors of delayed union according to variables of interest were investigated.

RESULTS

AO/OTA classification, site of fibula fracture, postoperative fracture gap, working length, and bone union rate of the two groups significantly differed (p<0.05). The cumulative rate of bone union during 1-year follow-up according to 43A tibia fracture, distal fibula fracture, fracture gap, and working length significantly differed between the two groups (p<0.05). By univariate Cox proportional hazards model, 43A tibia fracture, distal fibula fracture, facture gap, and short working length were risk factors for delayed union (p<0.05).

DISCUSSION

Non-actionable factors involving AO/OTA classification, distal fibula fracture and actionable factors including postoperative fracture gap, working length were significant factors affecting bone union after MIPO. The present study indicated that small fracture gap and long working length during MIPO might facilitate bone healing in tibia fracture.

LEVEL OF EVIDENCE

IV; single-center retrospective cohort study.

Biomechanical comparison of headless compression screws versus independent locking screw for intra-articular fractures

PURPOSE

Headless compression screws (HCS) have a variable thread pitch and headless design enabling them to embed below the articular surface and generate compression force for fracture healing without restricting movement. Locking screws have greater variety of dimensions and a threaded pitch mirroring the design of the HCS. The objective of this study is to determine whether locking screws can generate compression force and compare the compressive forces generated by HCS versus locking screws.

METHOD

A comparison between 3.5-mm HCS versus 3.5-mm locking screws and 2.8-mm HCS versus 2.7-mm locking screws was performed using a synthetic foam bone model (Synbone) and FlexiForce sensors to record the compression forces (N). The mean peak compression force was calculated from a sample of 3 screws for each screw type. Statistical analysis was performed using the one-way ANOVA test and statistical significance was determined to be p =  < 0.05.

RESULTS

The 3.5-mm Synthes and Smith and Nephew locking screws generated similar peak compression forces to the 3.5-mm Acutrak 2 headless compression screws with no statistically significant difference between them. The smaller 2.7-mm Synthes and Smith and Nephew locking screws initially generated similar compressive forces up to 1.5 and 2 revolutions, respectively, but their peak compression force was less compared to the 2.8-mm Micro Acutrak 2 HCS.

CONCLUSION

Locking screws are able to generate compressive forces and may be a viable alternative to headless compressive screws supporting their use for intra-articular fractures.

Conservative treatment versus transverse pinning in fifth metacarpal neck fractures in active adults: a randomized controlled trial

PURPOSE

Compare two simple ways for treating boxer's fractures in active adults; conservative management by ulnar gutter slab and transverse pinning in fixation of fifth metacarpal's neck fracture regarding union, functional outcomes, and complications.

PATIENTS AND METHODS

Ninety patients with fifth metacarpals' neck fractures with palmar angulation (30-70°) were managed either conservatively by an ulnar gutter slab or surgically by transverse pinning technique from January 2020 to December 2021. Only 84 patients completed a 1-year follow-up. Patients with old, open, or mal-rotated fractures were excluded. The block-randomization method was used to create equal groups. Patients were evaluated clinically and radiologically every 2-3 weeks until union, then at 6 and 12 months. Functional assessment at the final visit was done using the quick DASH score, total active motion (TAM), and total Active Flexion (TAF).

RESULTS

The mean radiological union time for the conservative group in this study was 7.76 weeks, while for the transverse pinning group, it was 7.38 weeks. There was no statistically significant difference between the two techniques regarding union rates and functional outcomes. All patients returned to their pre-injury jobs and level of activity.

CONCLUSION

Both conservative management in ulnar gutter slab and percutaneous transverse pinning are considered effective methods in the treatment of simple extra-articular fifth metacarpal neck fractures with angulation between 30 and 70 degrees (AO: 77 A3.1). The functional and radiological results using both methods were satisfactory and statistically comparable.

Zone 2 Fifth Metatarsal Fractures Treated Nonoperatively Have Similar Time to Healing to Those Treated Operatively

OBJECTIVES

To quantify the rate of union and time to clinical and radiographic healing in Zone 2 proximal fifth metatarsal (MT) fractures and compare these outcomes between Zone 2 fractures treated operatively and nonoperatively.

METHODS

DESIGN

Retrospective cohort study.

SETTING

Academic Level I Trauma Center.

PATIENT SELECTION CRITERIA

Patients with fifth MT fractures who presented between December 2012 and April 2022 and confirmed to have Zone 2 fractures (defined as fractures entering the proximal 4-5 MT articulation on the oblique radiographic view) were included in the study analysis in either the operative or nonoperative cohort.

OUTCOME MEASURES AND COMPARISONS

Nonunion, time to clinical healing by, and time to radiographic healing between operative and nonoperative treatment.

RESULTS

Among the 499 included patients, 475 patients (95.2%) were initially treated nonoperatively and 24 patients (4.8%) were treated operatively. Both groups were similar in demographics. There was no difference in the proportion of patients with nonunions between groups (6.1% in the nonoperative group vs. 3.8% in the operative group, P = 1.000). In addition, there was no statistically significant difference between groups with respect to the time to clinical healing (9.9 ± 8.3 weeks for the nonoperative group vs. 15.4 ± 15.0 weeks for the operative group, P = 0.117) or the time to radiographic healing (18.7 ± 12 weeks for the nonoperative group vs. 18.5 ± 16.6 weeks for the operative group, P = 0.970).

CONCLUSIONS

Zone 2 fifth MT base fractures were successfully treated with nonoperative management. There was no evidence in this study that operative treatment leads to significantly faster clinical or radiographic healing.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

MAGP2 promotes osteogenic differentiation during fracture healing through its crosstalk with the β-catenin pathway

Osteogenic differentiation is important for fracture healing. Microfibrial-associated glycoprotein 2 (MAGP2) is found to function as a proangiogenic regulator in bone formation; however, its role in osteogenic differentiation during bone repair is not clear. Here, a mouse model of critical-sized femur fracture was constructed, and the adenovirus expressing MAGP2 was delivered into the fracture site. Mice with MAGP2 overexpression exhibited increased bone mineral density and bone volume fraction (BV/TV) at Day 14 postfracture. Within 7 days postfracture, overexpression of MAGP2 increased collagen I and II expression at the fracture callus, with increasing chondrogenesis. MAGP2 inhibited collagen II level but elevated collagen I by 14 days following fracture, accompanied by increased endochondral bone formation. In mouse osteoblast precursor MC3T3-E1 cells, MAGP2 treatment elevated the expression of osteoblastic factors (osterix, BGLAP and collagen I) and enhanced ALP activity and mineralization through activating β-catenin signaling after osteogenic induction. Besides, MAGP2 could interact with lipoprotein receptor-related protein 5 (LRP5) and upregulated its expression. Promotion of osteogenic differentiation and β-catenin activation mediated by MAGP2 was partially reversed by LRP5 knockdown. Interestingly, β-catenin/transcription factor 4 (TCF4) increased MAGP2 expression probably by binding to MAGP2 promoter. These findings suggest that MAGP2 may interact with β-catenin/TCF4 to enhance β-catenin/TCF4's function and activate LRP5-activated β-catenin signaling pathway, thus promoting osteogenic differentiation for fracture repair. mRNA sequencing identified the potential targets of MAGP2, providing novel insights into MAGP2 function and the directions for future research.

Not Just Small Adults: Operative Versus Nonoperative Treatment in Adolescent Tibial Shaft Fractures

BACKGROUND

The standard of care for tibial shaft fractures in young children is nonoperative management, while in adults, operative treatment is considered the mainstay. There are no clear guidelines on preferred treatment for adolescents.

PURPOSE

This paper aims to 1) identify clinical and radiographic characteristics predictive of malalignment and 2) determine if treatment type affects malalignment risk.

METHODS

This retrospective cohort study identified patients aged 12 to 16 years old with a tibial shaft fracture at a Level 1 pediatric trauma center. The primary outcome of interest was malalignment, classified as meeting one or more of the following: >5° coronal angulation, >5° sagittal angulation, translation (cortical width or 100% displaced), and/or rotational deformity. Comparative analyses were done to identify risk factors for malalignment.

RESULTS

A total of 162 patients were included-initial treatment was "planned nonoperative" for 102 patients and "planned operative" for 60 patients. The malalignment rate was 34% in the planned nonoperative group versus 32% in the planned operative group. In a multivariate regression, older patients [odds ratio (OR)=-0.07, 95% CI: -0.13 to -0.01; P =0.024] and those with 100% initial displacement (OR=-0.35, 95% CI: -0.64 to -0.05; P =0.021) had decreased odds of malalignment, and having increased sagittal angulation (OR=0.02, 95% CI: 0.01-0.04; P =0.002) and a fibula fracture (OR=0.22, 95% CI: 0.03-0.41; P =0.023) increased the odds of malalignment. There was no difference in the rate of malalignment by initial treatment ( P =0.289). Having a planned nonoperative treatment (OR=22.7, 95% CI: 14.0-31.5; P <0.001) and having a fibula fracture (OR=8.52, 95% CI: 0.59-16.45; P =0.035) increased the time immobilized.

CONCLUSIONS

This study provides insight into factors affecting tibial shaft fracture alignment among patients aged 12 to 16 years. This study suggests that the risk of malalignment is higher among patients with increased initial sagittal angulation and concomitant fibula fractures, but the risk of malalignment is comparable in patients initially treated nonoperatively and operatively. Although healing parameters on average were similar, nonoperative treatment results in longer immobilization time and time for unrestricted weight bearing.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Photodynamic bone stabilization for traumatic and pathologic fractures: a systematic review of utilization, complications, and patient-reported outcomes

INTRODUCTION

The photodynamic bone stabilization system (PBSS) was was developed in 2010, and in 2018 gained FDA approval in the United States. Given its relative novelty, our analysis sought to analyze the available literature exploring the indications, outcomes, and complications of the PBSS.

METHODS

We performed a systematic review (PROSPERO registration of study protocol: CRD42022363065, October 8th, 2022). PubMed, EBSCOHost, and Google Scholar electronic databases were queried to identify articles evaluating PBSS in the treatment of pathologic or traumatic fractures between January 1 2010 and 15 October 2022. The quality of the included studies was assessed using the Methodological Index for Nonrandomized Studies tool.

RESULTS

Our initial search yielded 326 publications, which were then screened for appropriate studies that aligned with the purpose of our review. A total of thirteen studies, comprising seven case series, four case reports, and two cohort studies. The total sample size of the included studies consisted of 345 patients, with 242 females (70%) and 103 males (30%). The implants were most commonly utilized in the humerus (41%), radius (12%), and metacarpal (12%). The most common complications were related to broken implants (5%) and dislocation (1%). Most studies reported complete fracture healing and return of full strength and range of motion.

CONCLUSION

Despite being a relatively novel technology, PBSS appears to be a viable option for fracture stabilization. Most studies included in our analysis reported complete fracture healing and return of function with minimal complications.

Operative versus non-operative treatment of extra-articular distal humeral shaft fractures: a retrospective comparative study evaluating clinical and radiological outcomes

PURPOSE

There is limited evidence for comparing operative and non-operative management of closed, extra-articular distal humeral shaft fractures. This study aims to evaluate these outcomes.

METHODS

A comparative retrospective study was performed for patients who underwent either operative fixation or conservative management with a humeral brace, with clinical and radiological outcomes at minimum 2-year follow-up.

RESULTS

Forty-two patients with median 4.6 years follow-up were included; 24 had surgical fixation and 18 were managed with humeral brace. Assessment of clinical and radiological outcomes demonstrated few statistically significant functional differences between the two groups. Surgical patients achieved faster union for non-comminuted fractures. All patients maintained functional range of motion, with similar complication rates.

CONCLUSION

This study suggests that similar outcomes can be achieved with both managements, though faster union times may be seen in the operative group. Further studies are recommended to evaluate the impact of fracture comminution causing delayed unions.

MiR-22-3p facilitates bone marrow mesenchymal stem cell osteogenesis and fracture healing through the SOSTDC1-PI3K/AKT pathway

Bone fractures are the most common form of musculoskeletal trauma worldwide. Numerous microRNAs (miRNAs) have been suggested to be participants in regulating bone-related diseases. Recent studies revealed the regulatory role of miR-22-3p in osteogenic differentiation, but its role in fracture healing has not been investigated previously. Here, a rat femoral fracture model was established, Bone marrow mesenchymal stem cells (BMSCs) were isolated to detect the specific function and underlying mechanisms of miR-22-3p. MiR-22-3p and sclerostin domain-containing 1 (SOSTDC1) expression was determined by RT-qPCR and immunohistochemistry staining. The levels of proteins associated with osteogenic differentiation were assessed by western blotting. Flow cytometry was conducted to identify the isolated rat BMSCs. Alizarin red staining, alkaline phosphatase staining and Oil Red O staining were used to evaluate the osteogenic and adipogenic differentiation of rat BMSCs. The interaction between miR-22-3p and SOSTDC1 was verified using a luciferase reporter assay. Haematoxylin and Eosin (H&E) staining of the bone tissues was performed to analyse the effect of miR-22-3p on histopathological changes in vivo. MiR-22-3p was downregulated in the callus tissues of rat femoral fracture, while the expression of SOSTDC1 was upregulated. The isolated rat BMSCs had the capacity for both osteogenic and adipogenic differentiation. The differentiation capacity of BMSCs into osteoblasts was increased by miR-22-3p overexpression. MiR-22-3p activated the PI3K/AKT pathway by targeting SOSTDC1. SOSTDC1 overexpression and PI3K/AKT signalling inhibitor LY294002 abolished the enhancing effect of miR-22-3p overexpression on the osteogenesis of BMSCs. Thus MiR-22-3p facilitated the femoral fracture healing in rats. MiR-22-3p overexpression promoted fracture healing via the activation of PI3K/AKT pathway by targeting SOSTDC1.

A magnesium screw with optimized geometry exhibits improved corrosion resistance and favors bone fracture healing

Stress-induced corrosion impairs the mechanical integrity of magnesium (Mg) and its alloys as potential orthopedic implants. Although there has been extensive work reporting the effects of stress on Mg corrosion in vitro, the geometric design principles of the Mg-based orthopedic devices still remain largely unknown. In this work, a numerical simulation model mimicking fractured bone fixation and surgical animal models were applied to investigate the effects of the geometric design of Mg screws on the stress distribution and the stress-induced degradation behavior. Finite element (FE) analysis was used for calculation of stress concentrations around the Mg screws, with different thread type, thread pitch, and thread width. Afterward, the Mg screws of the pre-optimization and post-optimization groups exhibiting the highest and lowest stress concentrations, respectively, were implanted in the fractured distal femora and back subcutaneous tissue of rabbits. Encouragingly, there was a significant difference between the pre-optimization and the post-optimization groups in the degradation rate of the stressed screw parts located around the fracture line. Interestingly, there was no significant difference between the two groups in the degradation rate of the non-stressed screw parts. Consistently, the Mg screw post-optimization exhibited a significantly lower degradation rate than that pre-optimization in the back subcutaneous implantation model, which generated stress in the whole screw body. The alteration in geometric design did not affect the corrosion rate of the Mg screws in an immersion test without load applied. Importantly, an accelerated new bone formation with less fibrous encapsulation around the screws was observed in the Mg group post-optimization relative to the Mg group pre-optimization and the poly (lactic acid) group. Geometry optimization may be a promising strategy to reduce stress-induced corrosion in Mg-based orthopedic devices. STATEMENT OF SIGNIFICANCE: Stress concentrations influence corrosion characteristics of magnesium (Mg)-based implants. The geometric design parameters, including thread type, thread pitch, and thread width of the Mg screws, were optimized through finite element analysis to reduce stress concentrations in a fractured model. The Mg screws with triangular thread type, 2.25 mm pitch, and 0.3 mm thread width, exhibiting the lowest maximum von Mises stress, showed a significant decrease in the volume loss relative to the Mg screws pre-optimization. Compared with the Mg screw pre-optimization and the poly(lactic acid) screw, the Mg screw post-optimization favored new bone formation while inhibiting fibrous encapsulation. Collectively, optimization in the geometric design is a promising approach to reduce stress-induced corrosion in Mg-based implants.

IL-17RA Signaling in Prx1+ Mesenchymal Cells Influences Fracture Healing in Mice

Fracture healing is a complex series of events that requires a local inflammatory reaction to initiate the reparative process. This inflammatory reaction is important for stimulating the migration and proliferation of mesenchymal progenitor cells from the periosteum and surrounding tissues to form the cartilaginous and bony calluses. The proinflammatory cytokine interleukin (IL)-17 family has gained attention for its potential regenerative effects; however, the requirement of IL-17 signaling within mesenchymal progenitor cells for normal secondary fracture healing remains unknown. The conditional knockout of IL-17 receptor a (Il17ra) in mesenchymal progenitor cells was achieved by crossing Il17raF/F mice with Prx1-cre mice to generate Prx1-cre; Il17raF/F mice. At 3 months of age, mice underwent experimental unilateral mid-diaphyseal femoral fractures and healing was assessed by micro-computed tomography (µCT) and histomorphometric analyses. The effects of IL-17RA signaling on the osteogenic differentiation of fracture-activated periosteal cells was investigated in vitro. Examination of the intact skeleton revealed that the conditional knockout of Il17ra decreased the femoral cortical porosity but did not affect any femoral trabecular microarchitectural indices. After unilateral femoral fractures, Il17ra conditional knockout impacted the cartilage and bone composition of the fracture callus that was most evident early in the healing process (day 7 and 14 post-fracture). Furthermore, the in vitro treatment of fracture-activated periosteal cells with IL-17A inhibited osteogenesis. This study suggests that IL-17RA signaling within Prx1+ mesenchymal progenitor cells can influence the early stages of endochondral ossification during fracture healing.

Plate augmentation and hybrid bone grafting are effective treatments for atrophic nonunion of the femur with the original intramedullary nail retained in situ

The purpose of this study is to evaluate the efficacy of plate augmentation and hybrid bone grafting for treating atrophic nonunion of the femur with original intramedullary nail retained in situ.In this study, 36 patients with atrophic nonunion of the femur who underwent surgery using the technique of plate augmentation and a hybrid bone grafting while retaining the original intramedullary nail in situ in Xi'an Honghui Hospital from January 2019 to December 2021 were enrolled. 28 patients who met the inclusion and exclusion criteria were ultimately included in the study. These 28 patients, consisting of 20 males and 8 females with a mean age of 38 years, were evaluated based on factors such as operation time, intraoperative blood loss, the average hospitalization days. Additionally, the results and function of these patients were evaluated by union time, Wu's scores of limb function and incidence of serious complications.All 28 patients achieved bone union at the 12 month follow-up, with an average follow-up time of 14.6 ± 4.2 months.The average operation time was 68.3 ± 11.2 min, and the average intraoperative blood loss was 140 ± 22.6 ml. Patients were hospitalized for an average of 5.8 ± 1.1 days. Full clinical and radiological bone union was achieved on average at 5.1 ± 1.9 months. The mean value of Wu's scores at the 12 month follow-up was significantly higher than before the operation. Limb function was excellent in 27 patients and good in one patient at the 12 month follow-up. However, five patients experienced the lower limb vein thrombosis, including one deep vein thrombosis and four lower limb intermuscular vein thromboses. One patient had a superficial infections of the surgical incision site, while three patients reported pain and numbness where their iliac bone graft was extracted at the 12 month follow-up. The technique of plate augmentation and hybrid bone grafting, combined with retaining the original intramedullary nail in situ has been shown to be a safe, effective, simply and standardizable practice for treating atrophic femoral nonunion with an intact original IMN fixation.

Close negative correlation of local and circulating Dickkopf-1 and Sclerostin levels during human fracture healing

Wnt signaling is critically involved in fracture healing. Existing data predominantly relies on rodent models. Here, we explored local and circulating Dickkopf-1 (DKK1) levels in patients with respect to fracture healing and explore its association to sclerostin (SOST). 69 patients after surgical stabilization of long bone fractures of which six patients had impaired fracture healing were included in this study. Life-style and patient related factors with a known effect on DKK1 and SOST were recorded. DKK1 and SOST concentrations were measured using enzyme-linked immunosorbent assay (ELISA) at the fracture site and in circulation. DKK1 and SOST showed a close inverse correlation. In fracture hematoma and immediately after trauma DKK1 levels were significantly reduced while SOST levels were significantly increased, compared to healthy control. Postoperatively, DKK1 peaked at week 2 and SOST at week 8, again demonstrating a close negative correlation. Age and smoking status affected the balance of DKK1 and SOST, while type 2 diabetes and sex did not demonstrate a significant influence. Early postoperative elevation of SOST without compensatory DKK1 decrease was associated with fracture non-union in younger patients (< 50a). The close inverse correlation and very rapid dynamics of DKK1 and SOST locally as well as systemically suggest their critical involvement during human fracture healing. Importantly, as immediate compensatory feedback mechanism are apparent, we provide evidence that dual-blockade of DKK1 and SOST could be critical to allow for therapeutic efficiency of Wnt targeted therapies for fracture healing.

Approach to Tibial Shaft Nonunions: Diagnosis and Management

The tibia is the most common long bone at risk for nonunion with an annual incidence ranging from 12% to 19%. This topic continues to be an area of research as management techniques constantly evolve. A foundational knowledge of the fundamental concepts, etiology, and risk factors for nonunions is crucial for success. Treatment of tibial shaft nonunions often requires a multidisciplinary effort. This article provides guidance based on the most recent literature that can be used to aid the treating provider in the diagnosis, workup, and management of tibial shaft nonunions.

Flexible nailing: Pushing the indications for diametaphyseal lower-extremity fractures

Elastic stable intramedullary nailing (ESIN) has been shown to be an effective form of surgical management for lower-extremity diametaphyseal fractures in pediatric patients, but studies are limited because ESIN treatment for these fractures is relatively uncommon. We sought to determine whether ESIN can be used effectively in the most distal or proximal short-segment forms of these fractures. We queried the electronic medical record system at Johns Hopkins Hospital using Current Procedural Terminology codes for femur and tibia fractures treated with ESIN in patients under 18 years old between January 2015 and October 2022. Preoperative and postoperative radiographs were subsequently reviewed to identify patients with a proximal or distal third femoral or tibial shaft fracture treated with ESIN and to define criteria for short-segment diametaphyseal fractures. We used Beaty radiological criteria to evaluate radiographic outcomes and Flynn titanium elastic nails (TENs) outcome scale to assess clinical recovery after radiographic evidence of union. There were 43 children who met the inclusion criteria. Among them, 10 patients had short-segment diametaphyseal fractures. There were 22 (51.2%) who sustained femur fractures and 21 (48.8%) who sustained tibia fractures. Using Beaty radiologic criteria, ESIN was associated with more satisfactory outcomes in patients with distal or proximal third shaft fractures (32/33) than in patients with short-segment diametaphyseal fractures (7/10) (P = .03). Using the TENs outcome scale, 21 (63.4%) patients with distal or proximal third shaft fractures had excellent results, 11 (33.3%) had satisfactory results, and 1 (3%) had a poor result. Among patients with short-segment diametaphyseal fractures, 4 (40%) had excellent results, 5 (50%) had satisfactory results, and 1 (10%) had a poor result. There were no differences in TENs outcomes between the groups (P = .24). Patients with short-segment lower-extremity diametaphyseal fractures treated with ESIN had worse radiographic outcomes but did no worse clinically than patients with distal or proximal third shaft fractures. Consequently, ESIN should be considered a safe and effective surgical management option for pediatric patients with even the most distal or proximal forms of these fractures.

[A prospective study on treatment of Sanders type and calcaneal fractures with interlocking intramedullary nail fixation system]

Objective

To explore the effectiveness of interlocking intramedullary nail fixation system for Sanders type Ⅱ and Ⅲ calcaneal fractures by comparing with open surgery.

Methods

Forty patients (40 feet) with Sanders type Ⅱ and Ⅲ calcaneal fractures, who were admitted between May 2020 and December 2022 and met the selection criteria, were included in the study. They were randomly allocated into control group and minimally invasive group using a random number table method, with 20 cases in each group. The patients were treated with the interlocking intramedullary nail fixation system in the minimally invasive group and with steel plate internal fixation via a lateral L-shaped incision in the control group. There was no significant difference between the two groups ( P>0.05) in terms of gender, age, fracture classification and side, cause of injury, time from injury to admission, and preoperative width, length, height, Böhler angle, and Gissane angle of the calcaneus. The operation time, intraoperative blood loss, incision length, hospital stay, fracture healing time, incidence of complications, as well as pre- and post-operative imaging indicators (Böhler angle, Gissane angle, width, height, and length of the calcaneus) and American Orthopaedic Foot and Ankle Society (AOFAS) score of foot were recorded and compared between the two groups.

Results

The incision length, operation time, and hospital stay of the minimally invasive group were significantly shorter than those of the control group, and the intraoperative blood loss significantly reduced ( P<0.05). All patients of the two groups were followed up, with the follow-up time of 8-12 months (mean, 10.2 months) in the minimally invasive group and 8-12 months (mean, 10.4 months) in the control group. No complication occurred in the minimally invasive group after operation. One case of incision epidermal necrosis and 1 case of traumatic arthritis occurred in the control group after operation. However, there was no significant difference in the incidence of complications between the two groups ( P>0.05). At last follow-up, the AOFAS score was significantly higher in the minimally invasive group than in the control group ( P<0.05). Imaging examination showed that the calcaneal fractures of the two groups healed, and there was no significant difference in healing time between the two groups ( P>0.05). Compared with preoperative conditions, the Böhler angle and Gissane angle of the calcaneus in the two groups significantly increased, the width narrowed, and the height and length increased at 3 days after operation and the last follow-up, with significant differences ( P<0.05). There was no significant difference between 3 days after operation and last follow-up ( P>0.05). There was no significant difference between the two groups at each time point ( P>0.05).

Conclusion

The interlocking intramedullary nail fixation system in treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures has the advantages of minimal trauma, shortened hospital stay, reliable fracture reduction and fixation, and satisfactory foot function recovery.

Overexpression of miR-7-5p Promoted Fracture Healing Through Inhibiting LRP4 and Activating Wnt/β-Catenin Pathway

Background. The bone healing after fracture had a great impact on the patients' life quality. However, how miR-7-5p participated in fracture healing has not been investigated. Methods. For in vitro studies, the pre-osteoblast cell line MC3T3-E1 was obtained. The male C57BL/6 mice were purchased for in vivo experiments, and the fracture model was constructed. Cell proliferation was determined by CCK8 assay, and alkaline phosphatase (ALP) activity was measured by commercial kit. Histological status was evaluated using H&E and TRAP staining. The RNA and protein levels were detected via RT-qPCR and western blotting, respectively. Results. Overexpression of miR-7-5p increased cell viability and ALP activity in vitro. Moreover, in vivo studies consistently indicated that transfection of miR-7-5p improved the histological status and increased the proportion of TRAP-positive cells. Overexpression of miR-7-5p suppressed LRP4 expression while upregulated Wnt/β-catenin pathway. Conclusion. MiR-7-5p decreased LRP4 level and further activated the Wnt/β-catenin signaling, facilitating the process of fracture healing.

Treatment of presumed aseptic non-union of the humeral shaft by osteosynthesis combining intramedullary nailing and screw plate

In 2020, the most common treatment for presumed aseptic non-union of the humeral shaft seems to be decortication, often associated with bone autografting, and stabilized by a screw plate. We propose to evaluate an original technique of rigid osteosynthesis combining intramedullary nailing and screw plate. Between January 2004 and January 2020, 45 patients underwent treatment of presumed aseptic non-union of the humeral shaft by osteosynthesis combining intramedullary nailing and a screw plate. The minimum radio-clinical follow-up was one year postoperatively. The series included 19 men and 26 women with a mean age of 53 years (range 19-84 years). Bone consolidation was achieved in 43 patients, a rate of 95.5%. Comparing patients who achieved bone consolidation with the two failed consolidations did not reveal any statistically significant factor. Interobserver agreement was almost perfect (k=0.93) for the use of the RUST for humeral shaft fractures treated with intramedullary nailing and screw plate. In our study, the treatment of presumed aseptic non- union of the humeral shaft with an osteosynthesis combining intramedullary nailing and screw plate gives, with 95.5% of bone consolidation, results equal to or even superior to the different treatments currently described in the literature.

Primary Ankle Fusion Using an Antegrade Nail Into the Talus for Early Treatment of OTA Type C3 Distal Tibial Plafond Fractures: A Preliminary Report

BACKGROUND

Type C3 distal tibial plafond fractures consistently show poor outcomes with high complication rates and significant risk of posttraumatic arthritis. We describe a minimally invasive technique of performing a primary ankle fusion using an anterograde tibial nail and compare our early results to traditional methods of fixation.

METHODS

During the acute admission, the patient undergoes an arthroscopic preparation of the ankle joint and insertion of an anterograde nail into the talus. This technique is described in detail and presented alongside a retrospective 5-year review of all adult C3 distal tibial plafond fractures from our center.

RESULTS

Twenty-six patients (8 open fractures) had been fixed traditionally using open reduction internal fixation (24 patients) and circular frames (2 patients) with an average follow-up of 20 months. Those internally fixed had protected weightbearing for 3 months. Complications included deep infection (12%), nonunion (8%), malunion (4%), severe posttraumatic osteoarthritis (27%), and the secondary conversion to ankle replacement/fusion (12%) requiring an average of 3 reoperations.Six patients underwent primary fusion (3 open fractures) with an average follow-up of 18 months. Patients were allowed to immediately weightbear. There were no reported complications and the primary fusion group demonstrated shorter hospital stays, faster return to work, and higher mean self-reported foot and ankle score (SEFAS) compared to those treated with ORIF.

CONCLUSION

C3 distal tibial plafond fractures are difficult to manage and there has not been a satisfactory method of treating them that allows early return to work, has a low risk of complications, and reduces the risk of posttraumatic tibiotalar arthritis.We present our initial results with a method that uses traditional arthroscopic techniques to prepare the tibiotalar joint together with minimally invasive anterograde tibiotalar nailing. In this initial report of a small group of patients, we found that surgery can be performed once the swelling has subsided after injury and that allowing weightbearing as tolerated did not appear to have a negative effect on initial outcomes.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Technical aspects that may affect the outcomes of pediatric patients with both-bone forearm diaphyseal fractures treated using elastic stable intramedullary nails

We assessed the radiological and functional results of pediatric both-bone forearm diaphyseal fractures treated using elastic stable intramedullary nails (ESINs), as well as factors affecting the results. In total, 36 patients (33 males and three females; mean age, 11.6 years) were included. The mean follow-up time was 41.5 (18-96) months. Patient demographic characteristics and the details of the surgical techniques were analyzed retrospectively. In addition to standard radiographic evaluations, the ratio between the nail diameter and medullary canal diameter (ND/MCD) was measured, as well as the maximal radial bowing. According to the criteria of Price and Flynn, 28 (77.8%) and eight (22.2%) patients had excellent and good results, respectively. There were no cases of nonunion or delayed union. There was no significant difference in functional or radiological results according to whether titanium nails (24 patients) or stainless steel nails (12 patients) were used (all P  > 0.05). Nail prebending (performed in 19 patients) did not affect the functional or radiological results ( P  > 0.05). Loss of reduction was observed in four patients with an ND/MCD ratio <40%. The maximal radial bowing improved in all patients. The mean change was significantly greater in patients with diastases and 22D/4.1 fractures. Regardless of nail type or prebending status, surgery using ESIN placement effectively treats both-bone forearm diaphyseal fractures; radial bow remodeling outcomes are excellent. We recommend that the ND/MCD ratio should be 40-70%.

Comparing outcomes of plate augmentation, nail exchange, and nail exchange with plate augmentation in the treatment of atrophic femoral shaft nonunion after intramedullary nailing: a multicenter retrospective study

INTRODUCTION

Intramedullary (IM) nailing is the treatment of choice for femoral shaft fractures, but nonunion rates have been reported to be as high as 12%. Surgical interventions for nonunion involve exchange nailing or plate augmentation. Recently, a combined treatment of exchange nailing and plate augmentation has demonstrated good results, but its comparative effectiveness remains unclear. This study aimed to compare the clinical and radiographic outcomes of three different surgical interventions for atrophic femoral shaft nonunion, and investigate the factors that affect bone healing after reoperation.

MATERIALS AND METHODS

A retrospective study was conducted at five university hospitals involving 149 patients with aseptic atrophic nonunion after IM nailing. These patients underwent reoperation with plate augmentation, exchange nailing, or combined treatment. Clinical and radiographic outcomes were assessed and compared according to reoperation procedure. Logistic regression analysis was performed to identify factors affecting persistent nonunion after reoperation.

RESULTS

Of the cohort, 57 patients underwent plate augmentation, 64 underwent exchange nailing, and 28 received combined treatment. There were no significant differences in patient demographics among the groups. Exchange nailing produced a significantly lower union rate than did the combined treatment (82.8% vs. 100%, p = 0.016), whereas no significant difference was observed in the union rate and time to the union between plate augmentation and the combined treatment. Combined treatment showed the longest operative time and the greatest transfusion requirements. The risk factors for persistent nonunion included age, absence of autogenous bone grafts, and use of an exchange nailing technique.

CONCLUSIONS

Exchange nailing as a treatment for atrophic femoral shaft nonunion after IM nailing resulted in a lower union rate. The efficacy of the combined treatment requires further study, and persistent nonunion may be influenced by age, bone grafting, and surgical techniques. A comprehensive approach targeting both biological environment and mechanical stability is crucial in the treatment of atrophic femoral shaft nonunion.

Surgical Reconstruction of Canine Nonunion Fractures Using Bone Morphogenetic Protein-2-loaded Alginate Microbeads and Bone Allografts

BACKGROUND/AIM

Effective treatment of nonunion fractures is challenging as it requires a biological and mechanical environment to promote sufficient osteogenesis. Herein, we present a case series in which we evaluated the clinical efficacy of bone morphogenetic protein-2 (BMP-2)-loaded alginate microbeads and allografts in two dogs with nonunion fractures.

CASE REPORT

A 3-year-old, 2.3-kg, spayed female Pomeranian (Case 1) presented with intermittent lameness of the left forelimb after radial and ulnar fracture repair 8 weeks prior. A 4-year-old, 4.8-kg, spayed female Pomeranian (Case 2) was referred for non-weight-bearing lameness of the left hindlimb due to implant failure following left tibial fracture repair. Both dogs had atrophic bone ends and no bridging calluses at the fracture site on radiographs, and were diagnosed with nonviable nonunion fractures of the radius/ulna and tibia, respectively. The surgical approach involved implant removal, debridement, and fracture gap reconstruction. BMP-2 was loaded into alginate microbeads for a prolonged release with bone allograft chips in both cases. In Case 1, bead grafts were applied directly at the fracture site, while in Case 2, they were implanted inside a frozen cortical bone allograft as a scaffold to fill the large gap. Postoperative radiography revealed excessive callus formation, early radiographic bone union, and cortical bone remodeling, in line with improved lameness scores. At the final follow-up, gait was improved and the desired bone length and shape were achieved in both cases.

CONCLUSION

Simultaneous use of osteoinductive BMP-2 alginate microbeads and osteoconductive bone allografts yielded functionally and structurally favorable outcomes in canine nonunion fractures, without major complications.

Wound infection and healing in minimally invasive plate osteosynthesis compared with intramedullary nail for distal tibial fractures: A meta-analysis

To systematically explore the effects of minimally invasive plate osteosynthesis (MIPO) versus intramedullary nail (IMN) on wound infection and wound healing in patients with distal tibia fractures. A computerised search of PubMed, Web of Science, Cochrane Library, Embase, Wanfang, China Biomedical Literature Database (CBM) and China National Knowledge Infrastructure databases was performed, from their inception to October 2023, to identify relevant studies on the application of MIPO and IMN in patients with distal tibial fractures. The quality of the included literature was evaluated by two researchers based on inclusion and exclusion criteria, and basic information of the literature was collected, with wound infection, postoperative complications and wound healing time as the main indicators for analysis. Stata 17.0 software was applied for analysis. Overall, 23 papers and 2099 patients were included, including 1026 patients in the MIPO group and 1073 patients in the IMN group. The results revealed, when compared with IMN treatment, patients with distal tibia fractures who underwent MIPO treatment had a lower incidence of postoperative complications (OR = 0.33, 95% CI: 0.25-0.42, p < 0.001) and a shorter wound healing time (SMD = -1.00, 95% CI: -1.51 to -0.49, p < 0.001), but the incidence of postoperative wound infection was higher (OR = 2.01, 95% CI: 1.35-3.01, p = 0.001). Both MIPO and IMN are excellent treatments for distal tibia fractures. MIPO is effective in reducing the incidence of complications as well as shortening the time of wound healing time but increases the risk of wound infection. In clinical practice, surgeons can make individual choices based on the patient's wishes and proficiency in both techniques.

Macrophage-mediated fracture healing: Unraveling molecular mechanisms and therapeutic implications using hydrogel-based interventions

Fracture healing is a complex biological process that involves the orchestrated interplay of various cells and molecular signaling pathways. Among the key players, macrophages have emerged as critical regulators of fracture repair, influencing inflammation, tissue remodeling, and angiogenesis. Recent advances in hydrogel-based therapeutics have provided exciting opportunities to leverage the modulatory effects of macrophages for improving fracture healing outcomes. In the present study, we review the importance of macrophages in fracture repair and their potential therapeutic role in hydrogel-based interventions. We discuss the molecular mechanisms underlying macrophage-mediated effects on fracture healing, and how hydrogels can be utilized as a platform for macrophage modulation. Furthermore, we highlight the translation of hydrogel-based therapies from bench to bedside, including preclinical and clinical studies, and the challenges and opportunities in harnessing the therapeutic potential of macrophages in fracture repair. Overall, understanding the importance of macrophages in fracture healing and the potential of hydrogel-based therapeutics to modulate macrophage responses can pave the way for developing innovative approaches to improve fracture healing outcomes.

Outcomes of Humerus Nonunion Surgery in Patients With Initial Operative Fracture Fixation

OBJECTIVES

To describe outcomes following humerus aseptic nonunion surgery in patients whose initial fracture was treated operatively and to identify risk factors for nonunion surgery failure in the same population.

METHODS

DESIGN

Retrospective case series.

SETTING

Eight, academic, level 1 trauma centers.

PATIENTS SELECTION CRITERIA

Patients with aseptic humerus nonunion (OTA/AO 11 and 12) after the initial operative management between 1998 and 2019.

OUTCOME MEASURES AND COMPARISONS

Success rate of nonunion surgery.

RESULTS

Ninety patients were included (56% female; median age 50 years; mean follow-up 21.2 months). Of 90 aseptic humerus nonunions, 71 (78.9%) united following nonunion surgery. Thirty patients (33.3%) experienced 1 or more postoperative complications, including infection, failure of fixation, and readmission. Multivariate analysis found that not performing revision internal fixation during nonunion surgery (n = 8; P = 0.002) and postoperative de novo infection (n = 9; P = 0.005) were associated with an increased risk of recalcitrant nonunion. Patient smoking status and the use of bone graft were not associated with differences in the nonunion repair success rate.

CONCLUSIONS

This series of previously operated aseptic humerus nonunions found that more than 1 in 5 patients failed nonunion repair. De novo postoperative infection and failure to perform revision internal fixation during nonunion surgery were associated with recalcitrant nonunion. Smoking and use of bone graft did not influence the success rate of nonunion surgery. These findings can be used to give patients a realistic expectation of results and complications following humerus nonunion surgery.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparative Clinical Effects and Risk Factors Associated With Vitamin D in Foot and Ankle Fracture and Arthrodesis Healing

Vitamin D deficiency in relation to bone metabolism and healing has been controversial and not well studied. However, hypovitaminosis has been widely identified within the orthopedic patient population. The current best evidence suggests a lack of data on this important topic. The ability to assess patients for optimum bone healing and metabolism is still in question due to lack of a suitable reliable biomarker and multiple other unknown variables affecting bone metabolism. To compound this effect, popular dermatological precautions in the last 20 to 30 years of avoiding sunlight also have the effect of further reducing serum vitamin D production in the skin. As a proof of concept, we performed a preliminary comparative observational retrospective review of orthopedic patients undergoing fracture and arthrodesis osseous healing to determine how serum vitamin D levels are associated with bone healing along with their confounding comorbidities. Based on our review, the current accepted vitamin D levels (≥20 ng/mL) are low and insufficient for fractures and for arthrodesis osseous healing due to observed high rates (>35%) of delayed unions, and an increased (>90%) in the number of multiple confounding comorbidities affecting bone healing process that are often not mentioned or captured in this type of study in previous literature. Obesity and diabetes are significant contributory risks factors, and the preliminary findings suggest that the current accepted adequate levels may not be enough for osseous healing. These low vitamin D levels appear to affect bone healing and prolong treatment, with worsening trends with diabetes and obesity comorbidities.