Hand injuries in Kenya: a chaff cutter menace

Introduction Hand injuries are a recognized occupational hazard from the use of chaff cutters. With increasing mechanization of farming in our region, the burden of hand injuries is poised to increase. Methods We conducted a descriptive study of 47 patients presenting with chaff cutter hand injuries at our center in one year. Results They were predominantly male (98%) and the majority (70%) were aged between 21 and 40 years. The majority of patients who had not resumed work were those with severe injuries and those who had had an amputation. There was a positive correlation between age category and severity of injury. Discussion Chaff cutter injuries contribute considerably to hand amputations at our center. The majority of patients with severe injuries and those undergoing amputations do not return to gainful activities one year after sustaining the injury, suggesting increased dependency. Further research is paramount to identify safety features of chaff cutters in this region.

Use of graft materials and biologics in spine deformity surgery: a state-of-the-art review

PURPOSE

The aim of the current review is to summarize the current evidence on graft materials used in fusion procedures for spinal deformity corrections.

METHODS

PubMed, Embase, and Cochrane Library were searched for relevant published observational studies and clinical trials using osteobiologics and biomaterials in spinal deformity surgery.

RESULTS

The use of autograft in deformity correction surgeries has been reported in a limited number of studies, with the harvest sites including iliac crest, ribs, and local bone. Various allografts and biologics have been used in the treatment of spinal deformities including idiopathic and degenerative scoliosis, either as stand alone or in combination with autograft. Limited number of studies reported no differences in fusion rates or outcomes. Use of rh-BMP2 in anterior, posterior or front/back approaches showed higher fusion rates than other graft materials in patients with spinal deformities. Due to the limited number of quality studies included in the review, as well as alternative factors, such as costs, availability, and surgeon expertise/preference, no definitive conclusion or recommendations can be made as to the ideal graft choice in spinal deformity surgery.

CONCLUSIONS

Most commonly used grafts included autograft, allograft and rh-BMP2, with new biologics and biomaterials constantly emerging in the market. Limited number of high-quality comparative studies and heterogeneity in study design prevented direct comparisons that can lead to meaningful recommendations. Further studies are needed to prove superiority of any single graft material and/or biologic that is also cost-effective and safe.

Role of Fibular Allograft in Proximal Humerus Fractures: A Systematic Review

OBJECTIVES

To analyze the outcomes and complication rates of fibular allografts (FA) as an augmentation technique for proximal humeral fractures and determine their appropriate indications.

DATA SOURCES

English- and Spanish-language articles in PubMed, MEDLINE, Embase, Web of Science (Core Collection), and Google Scholar databases were systematically reviewed with the Preferred Reporting Items for Systematic Reviews guidelines on April 10, 2020.

STUDY SELECTION

Studies of patients with proximal humeral fractures treated primarily with FA and locking compression plates and with a minimum follow-up of 6 months were included, and presenting results with standardized clinical scales, radiological values, and operative complications.

DATA EXTRACTION

Two authors independently extracted data from the selected studies with a standardized data collection form. Subsequently, each extracted data set was consolidated on the agreement of authors.

DATA SYNTHESIS

From the initial screening of 361 articles, 5 case series and 6 retrospective cohort studies were included. A meta-analysis was not performed.

CONCLUSIONS

FA improved the clinical and radiological results, thereby reducing complications. The optimal indication for this procedure may be a 4-part fracture with medial column disruption in younger adults.

LEVEL OF EVIDENCE

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

Lower extremity fracture prevention and management in persons with spinal cord injuries and disorders: The patient perspective

CONTEXT/OBJECTIVE

To describe patient experiences with fracture prevention and management among persons with spinal cord injuries/disorders (SCI/D).

DESIGN

Qualitative data collected via semi-structured telephone interviews.

SETTING

Veterans Health Administration (VA) SCI/D System of Care.

PARTICIPANTS

Veterans with SCI/D (n = 32) who had experienced at least one lower-extremity fracture in the prior 18 months.

INTERVENTIONS

N/A.

OUTCOME MEASURES

Interview questions addressed patients': pre-fracture knowledge of osteoporosis and bone health, diagnosis and management of osteoporosis, history and experiences with fracture treatment, and post-fracture care and experiences.

RESULTS

Participants expressed concerns about bone health and fractures in particular, which for some, limited activities and participation. Participants recalled receiving little information from providers about bone health or osteoporosis and described little knowledge about osteoporosis prevention prior to their fracture. Few participants reported medication management for osteoporosis, however many reported receiving radiographs/scans to confirm a fracture and most reported being managed non-operatively. Some reported preference for surgical treatment and believed their outcomes would have been better had their fracture been managed differently. Many reported not feeling fully included in treatment decision-making. Some described decreased function, independence and/or participation post-fracture.

CONCLUSION(S)

Our results indicate that persons with SCI/D report lacking substantive knowledge about bone health and/or fracture prevention, and following fracture, feel unable and/or hesitant to resume pre-fracture participation. In addition, our findings indicate that individuals with SCI/D may not feel as engaged as they would like to be in establishing fracture treatment plans. As such, persons with SCI/D may benefit from ongoing discussions with providers about risks and benefits of fracture treatment options and consideration of subsequent function and participation, to ensure patients preferences are considered.

Masquelet's induced membrane technique associated with Reamer Irrigation Aspiration grafting and intramedullary Nailing (MaRIAN) for chronic diaphyseal osteomyelitis of the lower limb

INTRODUCTION

Masquelet's induced membrane technique offers a definitive contribution to the treatment of diaphyseal osteomyelitis. To overcome its drawbacks while maintaining its principles, technical modifications have been proposed: antibiotic cement, femoral intramedullary autograft harvested by RIA (Reamer Irrigation Aspiration) and interlocking nails.

MATERIAL AND METHOD

This retrospective study gathered patients with chronic osteomyelitis of the femur or tibia. The first surgical stage consisted of bone resection in the healthy zone and use of a gentamicin cement spacer to fill the bone defect. The second stage consisted of the placement of a statically locked intramedullary nail associated with a bone autograft using the RIA technique.

RESULTS

Among this group of 12 men with diaphyseal osteomyelitis; 9 tibial and 2 femoral, and 1 knee nonunion, the mean bone defect was 7.3cm (±6.7). The mean time between the 2 stages was 2.7months (±3) with a mean antibiotic period of 3.25weeks (±3). There was a femoral diaphyseal fracture at the donor site, and a wrong trajectory intraoperatively during the RIA. Two patients with tibial nonunion presented with nail rupture without septic recurrence. A septic recurrence was healed by removal of the nail. At a minimum follow-up of 18months, with an average of 5years, consolidation was complete without infectious recurrence. Despite the statistical weakness related to the size of the cohort, the resumption of early weight bearing (OR=-7.68 95% CI [-13.33 to -2.08] (p=0.01)) and nail dynamization seemed to have an impact on the formation of complete consolidation (OR=-0.86 95% CI [-1.39 to -0.33] (p=0.007)).

DISCUSSION AND CONCLUSION

This short series, compared to the literature, demonstrated that the proposed technical modifications improved the overall management of this rare and challenging condition while maintaining the reliability of the original technique. Dynamization was also seen to be of particular interest.

LEVEL OF EVIDENCE

IV, retrospective study.

Multimodular vascularized bone construct comprised of vasculogenic and osteogenic microtissues

Bioengineered bone designed to heal large defects requires concomitant development of osseous and vascular tissue to ensure engraftment and survival. Adult human mesenchymal stromal cells (MSC) are promising in this application because they have demonstrated both osteogenic and vasculogenic potential. This study employed a modular approach in which cells were encapsulated in biomaterial carriers (microtissues) designed to support tissue-specific function. Osteogenic microtissues consisting of MSC embedded in a collagen-chitosan matrix; vasculogenic (VAS) microtissues consisted of endothelial cells and MSC in a fibrin matrix. Microtissues were precultured under differentiation conditions to induce appropriate MSC lineage commitment, and were then combined in a surrounding fibrin hydrogel to create a multimodular construct. Results demonstrated the ability of microtissues to support lineage commitment, and that preculture primes the microtissues for the desired function. Combination of osteogenic and vasculogenic microtissues into multimodular constructs demonstrated that osteogenic priming resulted in sustained osteogenic activity even when cultured in vasculogenic medium, and that vasculogenic priming induced a pericyte-like phenotype that resulted in development of a primitive vessel network in the constructs. The modular approach allows microtissues to be separately precultured to harness the dual differentiation potential of MSC to support both bone and blood vessel formation in a unified construct.

No difference in clinical and radiological outcomes following fixation of transverse patella fractures with either suture tape or metallic cerclage: A retrospective comparative study

INTRODUCTION

Several surgical techniques have been proposed for the treatment of patellar fractures. The aim of this study is to compare the clinical efficacy and complication rates of treatment using suture tape circumferential cerclage (STCC) and metallic wire circumferential cerclage (MWCC) for the surgical treatment of displaced transverse patellar fractures (TPFs).

HYPOTHESIS

The hypothesis is that the use of the suture tape would be associated with a significantly lower rate of re-operation than metallic cerclage but no differences in other clinical outcomes.

PATIENTS AND METHODS

A retrospective comparative analysis of the clinical outcomes of consecutive patients undergoing fixation of TPFs with either MWCC or STCC between January 2017 and December 2018 was undertaken. All patients underwent evaluation with standardised radiographs at one, three, and six months after surgery to determine rates of union, non-union, loss of fixation and malunion. All patients underwent a final clinical evaluation at 18 months postoperatively to evaluate clinical scores and complications.

RESULTS

A total of 26 patients were included in the study. Thirteen patients underwent STCC and 13 underwent MWCC. There were no complications in the STCC group. In the MWCC group, one patient underwent hardware removal at 2 months postoperatively due to painful prominence. There was no significant difference in re-operation rates between the STCC and MWCC groups (p=1). There were no cases of non-union, malunion or loss of fixation throughout the series. At the final clinical follow-up of 18months, there were no significant differences in KSS, KOOS or Böstman scores between the groups.

CONCLUSION

No significant differences were identified when comparing the clinical outcomes of fixation of AO/OTA 34C1/2 fractures with suture tape or metallic cerclage fixation concerning re-operation rates, union rates, loss of fixation and functional outcome measures. These results cannot be extrapolated to more complex injury patterns or surgical techniques in which prominence of implanted material is more likely.

LEVEL OF EVIDENCE

III.

The effect of medial calcar support on proximal humeral fractures treated with locking plates

Background

Studies have reported mixed results on the importance of medial calcar support for the treatment of proximal humeral fractures. The purpose of this study was to compare radiographic and functional outcomes of patients who had displaced proximal humeral fractures with varying levels of medial support.

Methods

We performed a retrospective comparative cohort study. The study was conducted at a Level III trauma center in Taiwan. Seventy patients with proximal humeral fractures were collected retrospectively from 2015 to 2019. Only patients with two-, three-, or four-part types (Neer type I, II, or III) of displaced proximal humeral fractures were included in this study. However, patients with head-split fracture patterns, shoulder dislocation, prior shoulder trauma, and poor fracture reduction present in postoperative films were excluded. We assessed the radiographic outcomes, including the reduction score and amount of impaction in the humeral head. The functional outcome was evaluated based on the Constant score.

Results

Patients were grouped into the intact medial calcar group and the medial calcar deficiency group. In a subgroup analysis, the group with intact medial support had a significantly lower amount of impaction and a higher Constant score compared with the medial calcar deficiency group. Additionally, the groups with intact medial support had a nonsignificant difference in the Constant score between the affected side and the contralateral side.

Conclusion

The amount of impaction and the reduction score in the humeral head at the 12-month radiographic follow-up were significantly higher in the group with  medial support deficiency. However, the reduction score after surgery exhibited no difference. This implies that the inherent nature of medial comminution of proximal humeral fracture may lead to inferior radiographic outcomes.

Open latarjet procedure versus all-arthroscopic autologous tricortical iliac crest bone grafting for anterior-inferior glenohumeral instability with glenoid bone loss

PURPOSE

The purpose of this study is to compare the open Latarjet procedure versus the all-arthroscopic autologous tricortical iliac crest bone grafting (AICBG) technique for recurrent anterior-inferior glenohumeral instability with glenoid bone loss.

METHODS

All open Latarjet and AICBG procedures for recurrent anterior-inferior shoulder instability with glenoid bone loss performed at two institutions between September 2015 and April 2019 were retrospectively analyzed. Inclusion criteria were a traumatic etiology, a glenoid surface deficiency >13.5%, and a minimum follow-up (FU) of 18 months. Primary outcomes included the subjective shoulder value, the Western Ontario Shoulder Instability (WOSI), Rowe scores including subdomains, and the four subdomains of the Constant score (pain, activities of daily living, internal rotation, external rotation). Secondary outcomes were subjective shoulder instability, EQ-5D-3 L, pain level on the VAS, level of overall satisfaction, operative time, return-to-work rate, and return-to-sports rate.

RESULTS

Forty-three patients were available for final analysis (Latarjet: n = 21; AICBG: n = 22) at an average FU of 34.9 months (range, 22-66 months). Both techniques provided good outcomes and improved stability. The Rowe score, Rowe-range of motion, and CS-internal rotation (p = 0.008, p<0.001, p = 0.001) were slightly better in the AICBG group. Furthermore, the WOSI physical symptoms subdomain was significantly better (p = 0.04) in the AICBG group, while its total score did not reach statistical significance (p = 0.07). There was no statistically significant difference in the secondary outcomes besides operative time, which was significantly shorter in the Latarjet procedure group (p = 0.04). Overall complication rate was similar in both groups (Latarjet: 9.5% (n = 2), AICBG: 9.1% (n = 2)).

CONCLUSION

Open Latarjet and AICBG procedures provide comparable clinical outcomes except for significantly better Rowe score, Rowe-range of motion, WOSI physical symptoms subdomain, and internal rotation capacity in the AICBG group. However, these results should be carefully interpreted in the context of known minimal clinically important differences of these scores.

Importance of Lower Extremity Muscle Performance and Knee Proprioception During First 60 Degrees of Knee Flexion at Three Months After Anterior Cruciate Ligament Reconstruction

Background: Knee proprioception and neuromuscular control may be important factors contributing to re-injury occurrences. Objectives: To examine lower extremity muscular performance and knee proprioception preoperatively and 3 months after anterior cruciate ligament (ACL) reconstruction. Methods: Twelve participants underwent ACL reconstruction using the hamstring tendon. All participants were assessed for knee proprioceptive sense using an isokinetic dynamometer at 15° and 60° of knee flexion. Lower extremity muscular performance was examined using the single-leg squat test (SLS) with two-dimensional motion analysis in frontal and sagittal planes. Results: Mean absolute error angle at a 15-degree-target angle was significantly lower at three months after ACL reconstruction compared with the preoperative state (P = 0.04). Maximal knee flexion angle of the injured The SLS test showed a lesser knee flexion angle of the injured knee at three months after ACL reconstruction (P = 0.01), and injured knee proprioception at 60 degree-flexion did not significantly improve at the three month-postoperative stage. Conclusions: At three months after ACL reconstruction by hamstring graft tendon, knee proprioceptive sense at an inner range of knee extension improved. However, proprioception at the middle range did not significantly develop. The range of hip and knee motions using SLS related to strength changes that the knee extensor needs to improve, especially in the middle range.

Modulation of Osteogenesis and Angiogenesis Activities Based on Ionic Release from Zn-Mg Alloys

The enhancement of osteogenesis and angiogenesis remains a great challenge for the successful regeneration of engineered tissue. Biodegradable Mg and Zn alloys have received increasing interest as potential biodegradable metallic materials, partially due to the biological functions of Mg²⁺ and Zn²⁺ with regard to osteogenesis and angiogenesis, respectively. In the present study, novel biodegradable Zn-xMg (x = 0.2, 0.5, 1.0 wt.%) alloys were designed and fabricated, and the effects of adding different amounts of Mg to the Zn matrix were investigated. The osteogenesis and angiogenesis beneficial effects of Zn²⁺ and Mg²⁺ release during the biodegradation were characterized, demonstrating coordination with the bone regeneration process in a dose-dependent manner. The results show that increased Mg content leads to a higher amount of released Mg²⁺ while decreasing the Zn²⁺ concentration in the extract. The osteogenesis of pre-osteoblasts was promoted in Zn-0.5Mg and Zn-1Mg due to the higher concentration of Mg²⁺. Moreover, pure Zn extract presented the highest activity in angiogenesis, owing to the highest concentration of Zn²⁺ release (6.415 μg/mL); the proliferation of osteoblast cells was, however, inhibited under such a high Zn²⁺ concentration. Although the concentration of Zn ion was decreased in Zn-0.5Mg and Zn-1Mg compared with pure Zn, the angiogenesis was not influenced when the concentration of Mg in the extract was sufficiently increased. Hence, Mg²⁺ and Zn²⁺ in Zn-Mg alloys show a dual modulation effect. The Zn-0.5Mg alloy was indicated to be a promising implant candidate due to demonstrating the appropriate activity in regulating osteogenesis and angiogenesis. The present work evaluates the effect of the Mg content in Zn-based alloys on biological activities, and the results provide guidance regarding the Zn-Mg composition in designs for orthopedic application.

Using the Greater Tuberosity as a Reference for Placement of Proximal Humerus Plates Leads to a High Rate of Calcar Screw Malposition

OBJECTIVES

Achieving calcar fixation is critical to minimize the failure of proximal humerus fractures repaired with proximal humeral locking plates (PHLPs). Many operative technique manuals reference the greater tuberosity (GT) for plate placement. The objective of this study was to examine the accuracy of calcar screw placement when PHLPs were placed based on distance from the GT.

METHODS

Twenty cadaveric specimens were acquired representing a height distribution across the US population. Thirteen different PHLPs were applied. A drill bit was placed through the designated calcar screw hole and measured on radiographs, with the inferior 25% of the head representing an ideal placement.

RESULTS

Three hundred fifty constructs were studied. In 28% of the specimens, the calcar screw was misplaced. In 20% of the specimens, it was too low, whereas in 8%, it was too high. The calcar screw missed low in 30% of patients shorter than 5 feet, 5.5 inches versus 8% of taller patients ( P = 0.007). It missed high in 13% of taller patients versus 2% of shorter patients ( P = 0.056). Calcar screws in variable-angle plates missed 0% of the time, whereas those in fixed-angle plates missed 36% of the time ( P = 0.003).

CONCLUSIONS

Placement of PHLPs based on distance from the GT results in unacceptable position of the calcar screw 28% of the time and up to 36% in fixed-angle plates. This could be further compounded if the GT is malreduced. Current technique guide recommendations result in an unacceptably high rate of calcar screw malposition.

Injuries after Forklift Trucks Accidents - Injury Patterns, Therapy and Outcome in the Context of the Statutory Accident Insurance

INTRODUCTION

The use of forklift trucks during work has a high accident potential. The aim of this study is to describe injury patterns, treatment and outcome after forklift truck accidents in the context of the employers' liability insurance association.

METHODS

Retrospective data collection of all cases between 2004 and 2019. Excluded were patients < 18 years, without follow-up or with definitive external treatment. Trauma mechanism, injury patterns and distribution, treatment, complications, time of incapacity for work, return to work and impairment of earning capacity were recorded.

RESULTS

Of 109 patients with 110 injuries, 52.7% showed isolated injuries and 47.3% combined injuries, which affected the lower extremity in 95 cases. There were fractures in 85.5%, including 32.7% in open form. The mean length of stay was 29.1 days (range 1 - 129); an indication for surgery was seen in 80.9%. Surgical treatment required an average of 3 interventions, with significantly more operations for soft tissue closure than for the fractures (p ≤ 0.023). Amputations were necessary in 8 cases; complications occurred in 29.1%. Return to work was possible in 90%, after a mean period of incapacity for work of 33.6 weeks. A total of 40% showed a pensionable impairment of earning capacity.

CONCLUSION

Accidents with forklift trucks result in complex lower extremities injuries with the need of multi-stage treatment and show relatively high complication rates. A return to work is often possible after a long period of convalescence, and a pensionable impairment of earning capacity often persists.

Delayed union, non-union and mal-union in 442 dogs

OBJECTIVES

(1) To estimate the prevalence of delayed union, non-union and mal-union in canine fractures; (2) to describe fracture, demographic, and treatment characteristics for these outcomes; (3) to identify risk factors for delayed or non-union.

STUDY DESIGN

Retrospective study.

SAMPLE POPULATION

Four hundred and forty two dogs (461 fractures).

METHODS

A review was conducted of clinical records and radiographs from 2 teaching hospitals. "Union," "delayed union," "non-union" and "mal-union" were defined, and fracture, demographic, treatment, and outcome variables described. Differences in proportions or medians between "union," "delayed union" and "non-union" were tested using χ² and Mann-Whitney U-tests for categorical and continuous variables respectively. Potential explanatory variables for "delayed or non-union" were tested using logistic regression to identify risk factors.

RESULTS

Median radiographic follow up was 53 days (14-282). Delayed union occurred in 13.9% of fractures (64/461), non-union in 4.6% (21/461), and mal-union in 0.7% (3/461). Risk factors for delayed or non-union were age (OR 1.21, 95% CI 1.12-1.31); comminuted fracture (OR 4.24, 95% CI 2.4-7.5); treatment with bone graft (all types) (OR 3.32, 95% CI 1.3-8.5); surgical site infection (OR 3.24, 95% CI 1.17-8.97), and major implant failure (OR 12.94, 95% CI 5.06-33.1).

CONCLUSION

Older dogs, dogs with comminuted fractures, surgical site infection, or major implant failure were at increased odds of delayed or non-union. Radius and ulna fractures in toy breed dogs were not at increased odds of delayed or non-union.

CLINICAL SIGNIFICANCE

The identified risk factors should inform fracture planning and prognosticating. The prognosis for radial fractures in toy breeds appears better than historically believed.

Is it as harmless as it appears? Thoracic traumas caused by Pat-Pat accidents

Aim: This study examines the morbidity and mortality of chest traumas due to Pat-Pat accidents, which is one of the most frequently used motor vehicles in agriculture, especially in mountainous regions in developing countries. Material and Method: This retrospective study included 57 patients who were followed up in a single center between November 2018 and 2021 for thoracic trauma due to a Pat-Pat accident. Patients' age, gender, position in the vehicle, trauma mechanism, trauma location and time, trauma-related pathologies, treatments, and length of stay in hospital and intensive care unit were examined. Results: The cases included 44 (77.2%) men and 13 (22.8%) women with a mean age of 49.93±20.9 years. Of the accidents, 54 (94.7%) occurred on rural roads, 35 (61.4%) occurred on weekdays, 29 (50.9%) occurred in spring, and 20 (35.1%) occurred in summer. The cases consisted of 37 (64.9%) drivers and 20 (35.1%) passengers, of which 31 (54.4%) were injured due to collision and 26 (45.6%) were injured due to vehicle overturning and being ejected from the vehicle. All cases had rib fractures, 8 (14%) had sternum fracture, 25 (43.9%) had pneumothorax, 36 (63.2%) had hemothorax, 22 (38.6%) had pulmonary contusion, and 2 (3.5%) had cardiac contusion. While 19 (33.3%) of the cases were discharged after evaluation and treatment in the emergency department, 30 (52.6%) were treated in the ward, and 8 (14%) were treated in the intensive care unit (ICU). Thirty-three patients underwent a surgical procedure. The mean hospital stay was 7.8 days, and the mean ICU stay was 5.47 days. Mortality developed in 3 (5.3%) cases. The rates of ICU admission and mortality were found to be higher in injuries caused by being ejected from the vehicle compared to injuries caused by impact (p

Injectable nanoporous microgels generate vascularized constructs and support bone regeneration in critical-sized defects

Large and aberrant bone fractures require ossification and concomitant vascularization for proper healing. Evidence indicates that osteogenesis and vessel growth are coupled in bone fractures. Although the synergistic role of endothelial cells has been recognized, vascularizing large bone grafts remains a challenge and has apprehended the clinical translation of engineered bone constructs. Here, we describe a facile method to fabricate vascularized constructs using chitosan and gelatin-based microgels that promote osteogenesis of human mesenchymal stromal cells (MSC) while supporting endothelial sprouting and network formation. The microgels are enzymatically degradable and had a high hydration rate with a volume swelling ratio of ~ 493% and a polymer density of ~ 431 mg/cm3, which is comparable to that of native skeletal tissues. AFM indentation of the surface showed an average Young's modulus of 189 kPa, falling in a range that is conducive to both osteogenesis and vasculogenesis. The osteogenic microgel containing chitosan, gelatin, and hydroxyapatite, mimicking the bone matrix, supported robust attachment, proliferation, and differentiation of MSC. On the other hand, the vasculogenic microgels containing only gelatin, enriched endothelial phenotype and enabled vascular networks formation when embedded in 3D matrices. Combining the two types of microgels created a hybrid construct that sustained the functions of both osteogenic and vasculogenic microgels and enhanced one another. Using a murine model, we also show that the osteogenic microgels regenerate bone in a critical-sized defect with > 95% defect closure by week 12. These multifunctional microgels can be administered minimally invasively and can conformally fill large bone defects. This work lays the foundation to establish principles of designing multiphasic scaffolds with tissue-specific biophysical and biochemical properties for regenerating vascularized and interfacial tissues.

Primary Teeth-Derived Demineralized Dentin Matrix Autograft for Unilateral Maxillary Alveolar Cleft during Mixed Dentition

This clinical report describes the immediate autograft of primary (milk) teeth-derived demineralized dentin matrix (DDM) granules for a 6-year-old boy with unilateral alveolar cleft. First, four primary teeth were extracted, crushed in an electric mill for 1 min, and the crushed granules were demineralized in 2% HNO₃ solution for 20 min. Simultaneously, the nasal mucoperiosteum was pushed upwards above the apices of the permanent central incisor adjacent to the cleft. The nasal and palatal openings were closed by suturing the mucoperiosteum on both sides of the cleft with absorbable threads. The wet DDM granules were grafted into the managed cleft triangle space, and a labial flap was repositioned. The radiographic images at 6 months showed the continuous hard tissues in the cleft area and DDM granules onto lateral incisor (22) and impacted canine (23). The 3D-CT views at 2 years showed impacted tooth (22) blocked by primary canine and the replacement of DDM granules by bone near teeth (22,23). At 4 years, tooth crown (22) was situated just under the mucous membrane, and teeth (22,23) erupted spontaneously until 6 years without a maxillary expansion and a tow guidance of canine. The DDM granules contributed to bone formation without the inhibition of spontaneous tooth eruption. We concluded that autogenous primary teeth DDM graft should become a minimally invasive procedure without bone harvesting and morbidities for unilateral alveolar cleft.

Serology and Comorbidities in Patients With Fracture Nonunion: A Multicenter Evaluation of 640 Patients

INTRODUCTION

This multicenter cohort study investigated the association of serology and comorbid conditions with septic and aseptic nonunion.

METHODS

From January 1, 2011, to December 31, 2017, consecutive individuals surgically treated for nonunion were identified from seven centers. Nonunion-type, comorbid conditions and serology were assessed.

RESULTS

A total of 640 individuals were included. 57% were male with a mean age of 49 years. Nonunion sites included tibia (35.2%), femur (25.6%), humerus (20.3%), and other less frequent bones (18.9%). The type of nonunion included septic (17.7%) and aseptic (82.3%). Within aseptic, nonvascular (86.5%) and vascular (13.5%) nonunion were seen. Rates of smoking, alcohol abuse, and diabetes mellitus were higher in our nonunion cohort compared with population norms. Coronary artery disease and tobacco use were associated with septic nonunion (P < 0.05). Diphosphonates were associated with vascular nonunion (P < 0.05). Serologically, increased erythrocyte sedimentation rate, C-reactive protein, parathyroid hormone, red cell distribution width, mean platelet volume (MPV), and platelets and decreased absolute lymphocyte count, hemoglobin, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and albumin were associated with septic nonunion while lower calcium was associated with nonvascular nonunion (P < 0.05). The presence of four or more of increased erythrocyte sedimentation rate, C-reactive protein, or red cell distribution width; decreased albumin; and age younger than 65 years carried an 89% positive predictive value for infection. Hypovitaminosis D was seen less frequently than reported in the general population, whereas anemia was more common. However, aside from hematologic and inflammatory indices, no other serology was abnormal more than 25% of the time.

DISCUSSION

Abnormal serology and comorbid conditions, including smoking, alcohol abuse, and diabetes mellitus, are seen in nonunion; however, serologic abnormalities may be less common than previously thought. Septic nonunion is associated with inflammation, younger age, and malnourishment. Based on the observed frequency of abnormality, routine laboratory work is not recommended for nonunion assessment; however, specific focused serology may help determine the presence of septic nonunion.

Establishment and Evaluation of a Rat Model of Medial Malleolar Fracture with Vascular Injury

Objective

A stable animal model was needed to study bone non‐union caused by insufficient blood supply, the main object of this paper is to develop a medial malleolar fracture model with controllable arterial vascular injuries in rats for revealing the biochemical mechanism of non‐union by insufficient blood supply.

Methods

A total of 18 rats were randomly divided into three equal groups: the Sham group, the Fracture group, and the Fracture + Vascular group. The animals were subjected to unilateral medial malleolar bone fracture and vascular injury using customized molding equipment. The fracture site was scanned by micro‐CT, and vascular injury was evaluated by laser Doppler flowmetry (LDF) 24 h after modeling. Histological examination (HE), alkaline phosphatase (ALP) and tartrate‐resistant acid phosphatase (TRAP) staining, immunohistochemistry and immunofluorescence were conducted on the medial malleolar fracture tissues of three rats randomly selected from each group 24 h after modeling. Subsequently, to further confirm the success of fracture modeling, the fracture sites of three other rats in each group underwent micro‐CT scanning again 6 weeks after surgery.

Results

The results of a 24 h micro‐CT showed that all rats used to create the fracture models showed controlled injury of the medial malleolus. The model was stable, and the satisfaction of the homemade equipment agreed with the expectation. LDF showed that the blood flow of rats in the Fracture + Vascular group decreased significantly 24 h after fracture injury, while collateral blood flow perfusion increased by 50% on average. The results of HE, ALP and TRAP staining in the medial malleolus showed that the number of osteoblasts (OBs) and osteoclasts (OCs) in the Fracture group increased significantly, but the number of OBs and OCs in the Fracture + Vascular group decreased sharply relative to the number in the Sham group 24 h later. Furthermore, immunohistochemistry and immunofluorescence results showed that the number of neovessels in the Fracture group was significantly increased, while the number of neovessels in the Fracture + Vascular group was significantly decreased, which was consistent with the above results. After 6 weeks of modeling, the micro‐CT results showed that the fractures in the Fracture group had healed substantially, while those in the Fracture + Vascular group had not.

Conclusion

This study provided a reproducible and stable experimental animal model for medial malleolar fractures with arterial injury.

A mechanobiological computer optimization framework to design scaffolds to enhance bone regeneration

The treatment of large bone defects is a clinical challenge. 3D printed scaffolds are a promising treatment option for such critical-size defects. However, the design of scaffolds to treat such defects is challenging due to the large number of variables impacting bone regeneration; material stiffness, architecture or equivalent scaffold stiffness—due it specific architecture—have all been demonstrated to impact cell behavior and regeneration outcome. Computer design optimization is a powerful tool to find optimal design solutions within a large parameter space for given anatomical constraints. Following this approach, scaffold structures have been optimized to avoid mechanical failure while providing beneficial mechanical stimulation for bone formation within the scaffold pores immediately after implantation. However, due to the dynamics of the bone regeneration process, the mechanical conditions do change from immediately after surgery throughout healing, thus influencing the regeneration process. Therefore, we propose a computer framework to optimize scaffold designs that allows to promote the final bone regeneration outcome. The framework combines a previously developed and validated mechanobiological bone regeneration computer model, a surrogate model for bone healing outcome and an optimization algorithm to optimize scaffold design based on the level of regenerated bone volume. The capability of the framework is verified by optimization of a cylindrical scaffold for the treatment of a critical-size tibia defect, using a clinically relevant large animal model. The combined framework allowed to predict the long-term healing outcome. Such novel approach opens up new opportunities for sustainable strategies in scaffold designs of bone regeneration.

Sacral osteotomy combined with triangular osteosynthesis in the treatment of malunion and nonunion of vertically displaced pelvic fractures

Background

Malunion and nonunion of vertically displaced pelvic fractures result in lower limb length discrepancies, claudication, and pain. There have been few previous reports of this type of corrective surgery for these old pelvic fractures. We present a surgical technique of sacral osteotomy combined with triangular osteosynthesis in the treatment of malunion and nonunion of vertically displaced pelvic fractures and report on its short-term clinical results.

Methods

We retrospectively reviewed nine patients (five males and four females) with malunion or nonunion of vertically displaced pelvic fractures treated with sacral osteotomy and triangular osteosynthesis from April 2015 to January 2020. The age ranged from 14 to 45 years (average, 30.7 years). The time from injury to deformity correction surgery ranged from 3 months to 5 years (average, 12.8 months). The vertical displacement of a unilateral hemipelvis was 3.0–4.5 cm (average, 3.80 cm). According to AO/OTA classification at the initial fracture, there are eight cases in type C1.3 and one case in type C3.3. Sacral osteotomy and triangular osteosynthesis were used in all nine patients. The degree of unilateral hemipelvic reduction was assessed postoperatively based on measurements from the anteroposterior (AP) X-ray. Majeed score and pain visual analog scale (VAS) were used to assess the therapeutic effect of the patients during follow-up.

Results

In all nine patients, postoperative AP X-ray showed correction displacement of 1.7–3.9 cm (average, 3.20 cm). All the patients were followed up for 6–36 months (average, 12.7 months). At the last follow-up, the Majeed score of pelvic fracture increased from an average of 53.9 points (30–84 points) preoperatively to 87.0 points (72–94 points), and the VAS score for pain decreased from an average of 6.0 points (4–8 points) preoperatively to 1.2 points (0–3 points). None had complications like infection, implant broken, screw loosening, iatrogenic nerve, and blood vessel injury.

Conclusion

Sacral osteotomy combined with triangular osteosynthesis for the treatment of pelvic malunion and nonunion caused by sacral fractures can correct significantly vertical displacement of a unilateral pelvis, prolong limb length, and reconstruct the stability of a pelvic ring, achieving good clinical results.

Does fusion status following posterolateral lumbar fusion in the treatment for stable lumbar degenerative spondylolisthesis affect the long-term surgical outcomes? A propensity score-weighted analysis of consecutive patients

BACKGROUND

The surgical strategy of lumbar degenerative spondylolisthesis (LDS) is controversial, especially regarding whether or not fusion should be used. Although some reports have indicated that decompression combined with fusion may be better than decompression alone in the treatment of LDS, the effect of fusion status after uninstrumented posterolateral lumbar fusion (PLF) on the outcomes of patients with stable LDS remains unknown. This study aimed to evaluate the surgical outcomes of uninstrumented PLF for stable LDS and clarify whether radiographic fusion status could affect surgical outcomes.

METHODS

A total of 93 consecutive patients who had undergone single-level uninstrumented PLF for Meyerding grade I LDS without preoperative dynamic instability with a minimum follow-up period of 5 years were retrospectively studied. Patients were divided into two groups: nonunion (52 patients) and union (41 patients). The primary outcomes were the 5-year percent recovery of postoperative Japanese Orthopaedic Association (JOA) scores, Oswestry Disability Index (ODI), Visual analog scale (VAS) scores, and reoperation rate. The outcome scores were compared between the groups using the inverse probability weighting method using propensity scores.

RESULTS

The union and nonunion groups had comparable weighted means of the 5-year postoperative clinical score for the percent recovery of the JOA score (70.2% vs. 71.1%, P = 0.86), ODI (14.5 vs.14.6, P = 0.98), VAS of low back pain (20.3 vs. 18.7 mm, P = 0.72), and VAS of leg pain (24.0 vs. 19.4 mm, P = 0.43). The reoperation rate was 2.4% (one case of adjacent segment pathology) in the union group and 0% in the nonunion group (P = 0.44).

CONCLUSION

The fusion status following uninstrumented PLF had no significant effect on the 5-year postoperative clinical outcomes and reoperation rate in patients with Meyerding grade I LDS without dynamic instability.

[Current trends in reverse fracture arthroplasty]

The reliable results of reverse arthroplasty have made this the preferred treatment method for non-reconstructable proximal humeral fractures. The individual consideration of the patient and the morphological features of the fractures are essential. Computed tomography (CT) images provide crucial information on the perfusion of the humeral head relevant for the prognosis and treatment. In this context a differentiation must be made between hard and soft criteria against a reconstruction. Tuberosities should be reduced whenever possible, because reverse arthroplasty with healed tuberosities provides a better range of motion and more strength for external rotation and anteversion, less complications and longer survival rates. In recent years the trend has been towards anatomical designs of prostheses with a humeral inclination of 135°. Revision rates for primary fracture prostheses are overall low with instability as the main reason for revision surgery, followed by periprosthetic fractures and infections. Reverse fracture arthroplasty has comparable or better clinical results compared to conservative treatment, osteosynthesis for geriatric patients, hemiarthroplasty and prosthesis implantation by elective surgery. Reverse arthroplasties, which were implanted in conditions of fracture sequelae, did not achieve significantly poorer clinical outcome at mid-term follow-up and can significantly improve shoulder function.

Controlled magnesium ion delivery system for in situ bone tissue engineering

Magnesium cation (Mg²⁺) has been an emerging therapeutic agent for inducing vascularized bone regeneration. However, the therapeutic effects of current magnesium (Mg) -containing biomaterials are controversial due to the concentration- and stage-dependent behavior of Mg²⁺. Here, we first provide an overview of biochemical mechanism of Mg²⁺ in various concentrations and suggest that 2-10 mM Mg²⁺in vitro may be optimized. This review systematically summarizes and discusses several types of controlled Mg²⁺ delivery systems based on polymer-Mg composite scaffolds and Mg-containing hydrogels, as well as their design philosophy and several parameters that regulate Mg²⁺ release. Given that the continuous supply of Mg²⁺ may prevent biomineral deposition in the later stage of bone regeneration and maturation, we highlight the controlled delivery of Mg²⁺ based dual- or multi-ions system, especially for the hierarchical therapeutic ion release system, which shows enhanced biomineralization. Finally, the remaining challenges and perspectives of Mg-containing biomaterials for future in situ bone tissue engineering are discussed as well.

Necrotizing Fasciitis of the Upper Extremity – A Review

Necrotizing fasciitis is a soft tissue infection that habitually originates from the fascial sheaths, expands at a volant pace, leads to extensive necrosis of the subcutaneous tissues, and eventually ends up in a life-threatening condition with notably elevated amputation and mortality rates. Factors that induce interruption of skin integrity, such as trauma or intravenous drug use, are the most common inciting events. Specific clinical signs heralding its presence are usually absent in the early stages, often resulting in misdiagnosis. Early recognition, prompt and aggressive surgical debridement, antibiotic use, and supportive care constitute the fundamental principles to lean on for a better prognosis. Necrotizing fasciitis of the upper extremity is relatively rare and consequently holds a limited place in the literature. Only a few studies assess it as a separate entity, with most of them being case reports or small case series. We, therefore, performed a review of the current literature, to assemble the dispersed results of different studies and clarify the various aspects of upper limb necrotizing fasciitis. In this systematic review, we present the epidemiological data, the causative events, the most frequent underlying diseases, the risk factors, the amputation and mortality rates, the pathogenic microorganisms, the clinical characteristics, the diagnostic tools, the medical and surgical management concerning necrotizing fasciitis of the upper limb. Finally, the results indicating its differentiation compared to necrotizing fasciitis of other anatomic sites are remarkably highlighted.

Pelvic Malunion: A Systematic Review, Dichotomy of Definitions and Treatment

Background and Objectives: Pelvic nonunion and malunion have been documented as rare complications in pelvic fractures and literature describing these topics is severely limited. Articles dedicated solely to pelvic malunion are nearly nonexistent. We conducted a literature search with the goal of providing a summary of the definition, causes, treatment strategies, and outcomes of pelvic malunion correction. Materials and Methods: An initial review of the literature was performed using the PubMed, ScienceDirect, and Cochrane Database of Systematic Reviews databases. Search terms used were “malunion” AND “pelvic” OR “pelvis”. Duplicate articles, non-English language articles without translations available and non-human subject studies were excluded. Results: Eleven original publications were found describing experiences with pelvic malunion. Seven of the articles were exclusively dedicated to the topic of pelvic fracture malunion, and only two reported on a series of patients treated for malunion with variably staged procedures. Most reports define pelvic pain as the main indication for surgical correction, along with gait disturbance, standing or sitting imbalance, and urinary or sexual dysfunction. Radiographically, vertical displacement of one to two centimeters and rotation of the hemipelvis of fifteen degrees or more have been described in defining malunion. No treatment algorithms exist, and each patient is treated with a unique work-up and operative plan due to the complexity of the problem. Only one series reported a patient satisfaction rate of 75% following malunion treatment. Conclusions: Pelvic malunion is a rare complication of pelvic ring injury and is seldom discussed in the literature. We found two small case series reporting exclusively on malunion treatment and complications. While some of the combination studies made the distinction in the diagnosis of malunion and nonunion, they rarely differentiated the treatment outcomes between the two categories. This paper describes pelvic malunion and highlights the need for more research into surgical outcomes of treatment specifically regarding functionality, patient satisfaction, and recurrence of preoperative symptoms.

Predictive Indicators for Complications of Proximal Humerus Fractures Treated with Locking Plate or Intramedullary Nail Fixation

Objective

The purpose of this study was to evaluate the best placement of calcar screws in proximal humerus fracture surgeries.

Methods

This retrospective cohort study included clinical and radiographic outcomes of 98 patients treated with proximal humerus fracture surgeries between January 2017 and June 2020. Demographic data of patients were obtained from medical records. The surgical and radiographic results were also collected: operation time, blood loss, time to surgery, fibular allograft, disruption of medial region hinge, Neer classification, and recovery of medial support. Patients were allocated into two groups: the locking plate group (n = 65) and the intramedullary nail group (n = 33). In this study, we proposed new predictive indicators, named horizontal ratio (HR) and vertical ratio (VR), to quantify the placement of calcar screws in these two groups. A receiver operating characteristic (ROC) analysis was conducted to display the accuracy of these indicators. Shoulder activity, visual scale analog (VAS) score, and Constant score were performed to evaluate postoperative clinical outcomes at 1 year follow‐up.

Results

In the multivariate logistic regression analysis, only time to surgery and effective medial support were considered statistically significant factors of postoperative complications (p < 0.05). Significant differences were observed between medial support and postoperative complications both in the locking plate group and the intramedullary nail group (p < 0.05). Only the vertical ratio of locking plate (VRLP) was a statistically significant predictor of postoperative complications (p < 0.05). The area under curve was calculated to assess the predictive value of VRLP, which came to 0.84. In addition, a ROC analysis found quantifiable thresholds of the VR was 0.1713 as measures to avoid postoperative complications in the locking plate fixation.

Conclusion

In locking plate fixation, the incidence of postoperative complications increased significantly when the VR of calcar screws greater than 0.1713, which was beneficial to surgeons to place calcar screws.

Endosteal plating in proximal humerus fractures: a novel technique and alternative to fibular strut allograft for medial column support

Hypothesis

The purpose of this retrospective study is to investigate the clinical and radiographic outcomes associated with the use of a standard metal plate as an endosteal implant in combination with a lateral locking plate to treat 4 patients with displaced proximal humerus fractures.

Methods

A retrospective case series study design was utilized, and the medical records of 4 patients with displaced, 3-part proximal humerus fractures treated using this technique between January 2019 and July 2021 were reviewed for this study. The mean age was 52 years (range, 44-57 years). The radiographic outcome of interest was humeral neck-shaft angle preoperatively, intraoperatively, and at the latest follow-up. The average follow-up duration was 62 weeks (range, 12-161 weeks).

Results

All fractures healed without loss of reduction or neurovascular deficits. Avascular necrosis was not observed in the 2 patients with sufficient follow-up time to make such an evaluation. The average neck-shaft angles preoperatively, intraoperatively, and at the latest follow-up were 104.8°, 139.8°, and 137°, respectively.

Conclusion

Locking plate technology augmented with an endosteal plate provided stable reduction and restoration of physiologic alignment in a small number of patients with displaced proximal humerus fractures. This construct creates a second column of fixation, providing medial column support, and could be removed in the event of a future revision to a reverse shoulder arthroplasty.

Treatment options in non-unions of the pelvis: A retrospective analysis of a single center experience over 12 years

BACKGROUND

Non-unions and chronic instability of the pelvis remain rare complications after complex high velocity injuries with vertical and rotational instability of the pelvis. Treatment options are insufficiently supported by data evidence due to the rareness of this condition.

PATIENTS AND METHODS

we conducted a single center, retrospective study of all non-unions and pelvic instabilities between 1.1.2008 and 1.1.2019, excluding fragility fractures. Patients' characteristics, fracture patterns, procedures and outcomes with regard to developing treatment options and successful union in the follow-up were obtained.

RESULTS

26 patients were included in this retrospective analysis. The mean age was 55 years (range 34-78 years). Seventy-seven percent of the patients were male. The standard procedure consisted of radical debridement of the non-union, interposition of autologous bone graft and rigid stabilization systems. Three patients were lost to follow up. In the remaining n = 23 patients (88%) consolidation of the non-union was achieved. The mean follow up was 31.3 months (range 6-144). Follow up showed that an iliolumbar fixation seems to be favorable regarding outcome and complications.

DISCUSSION

Non-union and remaining instability of the pelvic ring represent a rare complication after high grade pelvic trauma. There are only limited data regarding the incidence and the treatment regimen is based on small study populations only. Based on our findings we recommend to combine autologous bone grafts with rigid fixation systems especially for non-union of the pelvis to restore the posterior sacroiliac arch.

[Update on non-unions 2022 : Imaging diagnostics, classification and treatment algorithms]

BACKGROUND

Fracture healing is a complex regenerative process. An unconsolidated fracture that will not heal without further surgical intervention is called non-union. The causes are multifactorial. Diagnostic imaging is a central pillar and provides insights into the morphology and biology of the fracture as a basis for optimal surgical treatment decisions.

AIM

Knowledge of fracture healing, targeted radiological and nuclear medical diagnostics, and interdisciplinary standardized classification are of high importance for optimal treatment.

METHODS

In this article, the proven and modern diagnostic procedures are presented, an overview of the currently used scoring and classification models is given and the optimal therapeutic approach based on the extended "diamond concept" is addressed. A possible diagnostic and therapeutic approach is shown using an algorithm.

CONCLUSION

For successful treatment of pseudarthrosis, targeted radiological and nuclear medical diagnostics with old established but also newest methods, such as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and hybrid imaging, are necessary. An exact classification of non-unions using additional classification models makes it possible to determine and carry out the optimal surgical treatment at an early stage.

Donor site morbidity of calcaneal, distal tibial, and proximal tibial cancellous bone autografts in foot and ankle surgery. A systematic review and meta-analysis of 2296 bone grafts

PURPOSE

This study aims to report on the safety and donor site morbidity of the distal lower extremity (calcaneal, proximal, and distal tibial) cancellous bone autografts. We summarized the findings in a comprehensive infographic illustration. We are unaware of any similar meta-analyses to date.

METHODS

Following the PRISMA guidelines, two independent investigators searched MEDLINE (PubMed), EMBASE, SCOPUS, Google Scholar, and Cochrane databases in December 2020 using the following keywords and their synonyms: ("bone graft", "donor site morbidity", "calcaneal graft", "proximal tibia graft", and "distal tibia graft"). Besides, the reference lists from previous review articles were searched manually for eligible studies. The primary outcomes of interest were (1) chronic pain, (2) fracture, and (3) infection, whereas the secondary outcomes were (1) neurological complications, (2) sensory disturbance and hypertrophic scars, (3) other complications such as shoe-wear difficulties and gait disturbance. Inclusion criteria were: studies on complications and adverse events of lower extremity bone autografts (calcaneal, proximal tibial, and distal tibial bone autografts) reporting at least one of the desired outcomes. Studies not reporting any of the outcomes of interest or if the full text is not available in English were excluded. Studies reporting on bone marrow aspirate or autografts for non-orthopedic indications were also excluded.

RESULTS

After the removal of duplicates, a total of 5981 studies were identified. After screening those records, 85 studies remained for full-text assessment. Out of those, 15 studies qualified for the meta-analysis with a total of 2296 bone grafts. Out of those grafts, 1557(67.8%) were calcaneal grafts, 625 (27.2%) were proximal tibial grafts, and 114 (5%) were distal tibial grafts. In calcaneal bone grafts, there were 28 cases of chronic pain [1.97%, CI:1.10-2.50%, I² = 66%], 5 fractures [0.32%, CI: 0.10-0.60%,I² = 0%], 20 sural neuritis [1.28%, CI:0.70-1.80%, I² = 0%), and no wound infections. In proximal tibial grafts there were 13 cases of chronic pain [2.08%, CI: 1.01-3.2%, I² = 34.5%], 1 fracture [0.16%, CI:0.10-0.50%, I² = 0%], and 3 superficial wound infections [0.48%, CI: 0.10-1.01, I² = 0%]. In the distal tibial grafts there were no cases of chronic pain or wound infections, 1 fracture [0.90%, CI: 0.80-2.6%, I² = 0%], and 5 saphenous neuritis [4.5%, CI: 0.70-8.40%, I² = 65%].

CONCLUSION

Calcaneal, distal tibial, and proximal tibial bone autografts are safe with a low rate of overall and major complications. We report an overall complication rate of 6.8%, which is less than half of that previously reported for iliac crest grafts. The authors recommend using distal lower extremity grafts for foot and ankle primary surgeries instead of iliac crest grafts when indicated. Clinical trials with a large sample size are required.

Is it really necessary to perform venous anastomosis in vascularized corticoperiosteal bone flap? A randomized prospective 4-year follow-up study

BACKGROUND

This study aims to investigate the treatment results of atrophic nonunion of the lower and upper limb with vascularized bone flaps performed with only arterial anastomosis versus the execution of flaps performed with arterial and venous anastomosis, comparing the surgical time and the healing rate of these two techniques.

METHODS

49 patients were enrolled in this study and were randomly divided into two groups: group A, the control group, consisted of 27 patients, who underwent vascularized corticoperiosteal bone flap with both arterial and venous anastomosis; group B, consisted of 22 patients, who underwent vascularized corticoperiosteal bone flap with only arterial anastomosis. The surgical time, the time to harvest the graft and the microsurgical time were evaluated. Radiological and clinical follow-ups were performed with one independent and blinded investigator to avoid bias.

RESULTS

A significant reduction in the duration of the intervention in group B was found: a 13.63% reduction of the total surgical time and a 41.75% reduction of the microsurgical time. A significant difference was not found between groups A and B in bone healing time. All the patients of both groups were able to return to their daily life activities.

CONCLUSIONS

Our investigation suggests that it isn't necessary to perform the venous anastomosis between the flap pedicle and the recipient area. Presumably, the venous blood flow reaches the systemic circulation through the vascular bone marrow network. Our procedure avoids venous trauma during the dissection and execution of the anastomosis and, therefore, can minimize complications such as venous thrombosis.

Monomicrobial Necrotizing Fasciitis and Sepsis Caused by Pseudomonas aeruginosa and Pseudomonas fluorescens: A Series of Ten Cases

Monomicrobial necrotizing fasciitis caused by Pseudomonas species is a rare infection. The purpose of this study was to elucidate the specific characteristics and clinical outcomes of necrotizing fasciitis caused by Pseudomonas aeruginosa and Pseudomonas fluorescens. Ten patients with monomicrobial necrotizing fasciitis caused by Pseudomonas species were retrospectively reviewed over an 8-year period. Differences in mortality, patient characteristics, clinical presentations, laboratory data, and clinical outcomes were compared between the death and the survival groups. Two patients died with the mortality rate of 20%. Pseudomonas aeruginosa accounted for 9 patients and Pseudomonas fluorescens for one patient. The most common comorbidity is type 2 diabetes mellitus in 5 patients. We found the death patients had lower albumin level and higher counts of band forms of leukocytes than those of the survival patients. Monomicrobial necrotizing fasciitis caused by Pseudomonas species needs emergent surgical intervention and aggressive intensive care due to high mortality rate. We reported the first case of monomicrobial necrotizing fasciitis with Pseudomonas fluorescens. Severe hypoalbuminemia and increased counts of banded leukocytes in initial laboratory presentations can be considered as poor prognostic factors.

Surface polydopamine modification of bone defect repair materials: Characteristics and applications

Bone defects are a common challenge for clinical orthopedic surgeons. The existing bone defect repair materials are difficult to achieve satisfactory osseointegration between the material and the bone. Therefore, it is increasingly important to find effective methods to improve the integration of the materials with the bone and thus facilitate bone defect repair. Researchers have found that polydopamine (PDA) has a structure and properties similar to the adhesive proteins secreted by mussels in nature, with good biocompatibility, bioactivity, hydrophilicity, bio-adhesion and thermal stability. PDA is therefore expected to be used as a surface modification material for bone repair materials to improve the bonding of bone repair materials to the bone surface. This paper reviews research related to PDA-modified bone repair materials and looks at their future applications.

First detection of primary cilia in injured human anterior cruciate ligament: A pilot study with pathophysiological reflections

The anterior cruciate ligament (ACL) plays a significant role in knee stability, protects the joint under multiple loading conditions and shows complex biomechanics. Beside mechanical stability, the ACL seems to play a crucial role in proprioception, and it is well known, that ACL injuries can cause functional deficits due to decreased proprioception. However, the mechanism of proprioception is not completely understood yet. In this context, primary cilia (PC), which play a significant role in the signaling between the intra- and extracellular space, could be of interest. However, until today, primary cilia are not yet described in human ACL. In total, seven human ACL's underwent transmission electron microscopical examination. Three cadaveric ACL's and four freshly injured ACL's were examined. Single cells of each ACL were examined regarding the presence of axonemes or basal bodies, which represent components of a PC. In total, 276 cells of the cadaveric ACL's and 180 cells of the injured ACL's were examined. Basal bodies could be detected in three of the four specimens of the injured ACL's as well as in one of the three cadaveric ACL's, resulting in a mean positivity of 2.54% in the cadaveric group and 2.78% in the injured group. In case of PC-presence, only one PC per cell could be detected. No statistically significant difference regarding the frequency could be detected between both groups. In this pilot-study, we present for the first time an ultrastructural study of human ACLs with respect to the occurrence of PC and any structural and morphological features of these complex and dynamic cell organelles. PCs are present in almost all non-hematopoietic tissues of the human body. However, there are different reports on the number, incidence, orientation, and morphology of these cell organelles in the respective tissues. Compared to other tissues and ligaments of other species, we found a significantly lower rate of PC positive cells. This observation might represent a tissue-specific characteristic of ACL tissue. However, our observations need to be explored in more detail in further studies.

Preclinical evaluation of a prototype freehand drill video guidance system for orthopedic surgery

Purpose: Internal fixation of pelvic fractures is a challenging task requiring the placement of instrumentation within complex three-dimensional bone corridors, typically guided by fluoroscopy. We report a system for two- and three-dimensional guidance using a drill-mounted video camera and fiducial markers with evaluation in first preclinical studies. Approach: The system uses a camera affixed to a surgical drill and multimodality (optical and radio-opaque) markers for real-time trajectory visualization in fluoroscopy and/or CT. Improvements to a previously reported prototype include hardware components (mount, camera, and fiducials) and software (including a system for detecting marker perturbation) to address practical requirements necessary for translation to clinical studies. Phantom and cadaver experiments were performed to quantify the accuracy of video-fluoroscopy and video-CT registration, the ability to detect marker perturbation, and the conformance in placing guidewires along realistic pelvic trajectories. The performance was evaluated in terms of geometric accuracy and conformance within bone corridors. Results: The studies demonstrated successful guidewire delivery in a cadaver, with a median entry point error of 1.00 mm (1.56 mm IQR) and median angular error of 1.94 deg (1.23 deg IQR). Such accuracy was sufficient to guide K-wire placement through five of the six trajectories investigated with a strong level of conformance within bone corridors. The sixth case demonstrated a cortical breach due to extrema in the registration error. The system was able to detect marker perturbations and alert the user to potential registration issues. Feasible workflows were identified for orthopedic-trauma scenarios involving emergent cases (with no preoperative imaging) or cases with preoperative CT. Conclusions: A prototype system for guidewire placement was developed providing guidance that is potentially compatible with orthopedic-trauma workflow. First preclinical (cadaver) studies demonstrated accurate guidance of K-wire placement in pelvic bone corridors and the ability to automatically detect perturbations that degrade registration accuracy. The preclinical prototype demonstrated performance and utility supporting translation to clinical studies.

Sacral Insufficiency Fractures

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Primary osteoporosis is the most common cause of sacral insufficiency fractures (SIFs). Therefore, a multidisciplinary team approach is necessary for treatment of the fracture and the underlying biologic pathology, as well as prevention of future fragility fractures.

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The presentation of SIFs typically includes lower back or buttock pain after a ground-level fall or without an identified trauma. Symptoms often have an insidious onset and are nonspecific; consequently, a delay in diagnosis and treatment is common. Clinicians need to have a high index of suspicion, particularly in high-risk patients.

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Postmenopausal women who are >55 years of age are the most common demographic affected by SIFs. Other risk factors include osteoporosis, history of a prior fragility fracture, local irradiation, long-term corticosteroid use, rheumatoid arthritis, metabolic bone disorders, vitamin D deficiency, pregnancy, history of prior multilevel spinal fusion, and malignancy.

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Typical imaging on computed tomography (CT) shows sclerosis of cancellous bone in the sacral ala, with or without a discrete fracture line or displacement. Magnetic resonance imaging is more sensitive than CT and shows hypointense signal on T1-weighted sequences and hyperintensity on T2-weighted or short tau inversion recovery sequences.

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The treatment of SIFs is dependent on the severity of symptoms, fracture displacement, and instability of the pelvis. Accepted treatments include nonoperative rehabilitation, sacroplasty, iliosacral screw fixation, transsacral bar or screw fixation, transiliac internal fixation, and lumbopelvic fixation.

Perioperative Radiographic Predictors of Non-Union in Infra-Isthmal Femoral Shaft Fractures after Antegrade Intramedullary Nailing: A Case-Control Study

Antegrade intramedullary (IM) nailing is the gold standard treatment for femoral shaft fractures; however, the non-union rate of infra-isthmal femoral shaft fractures is still high after antegrade IM nailing. This retrospective case−control study aimed to determine the association between perioperative radiographic factors and the non-union of infra-isthmal femoral shaft fractures after antegrade IM nailing. Univariate and multivariate analyses were used to evaluate the radiographic risk factors of non-union. Ninety-three patients were included, with thirty-one non-unions and sixty-two matched controls between 2007 and 2017. All were regularly followed up for 2 years. Receiver operating characteristic analysis revealed that a ratio of the unfixed distal segment > 32.5% was strongly predictive of postoperative non-union. The risk factors for non-union were AO/OTA type B and C (odds ratio [OR]: 2.20), a smaller ratio of the distal fragment (OR: 4.05), a greater ratio of the unfixed distal segment (OR: 7.16), a higher ratio of IM canal diameter to nail size at the level of fracture (OR: 6.23), and fewer distal locking screws (OR: 2.31). The radiographic risk factors for non-union after antegrade IM nailing for infra-isthmal femoral shaft fractures were unstable fractures, shorter distal fragments, longer unfixed distal fragments, wider IM canal, and fewer distal locking screws. Surgeons must strive to avoid non-union with longer and larger nails and apply more distal locking screws, especially for unstable, wider IM canal, and shorter distal fragment fractures.

Interventions for treating proximal humeral fractures in adults

BACKGROUND

Fractures of the proximal humerus, often termed shoulder fractures, are common injuries, especially in older people. The management of these fractures varies widely, including in the use of surgery. This is an update of a Cochrane Review first published in 2001 and last updated in 2015.

OBJECTIVES

To assess the effects (benefits and harms) of treatment and rehabilitation interventions for proximal humeral fractures in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, trial registries, and bibliographies of trial reports and systematic reviews to September 2020. We updated this search in November 2021, but have not yet incorporated these results.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials that compared non-pharmacological interventions for treating acute proximal humeral fractures in adults.  DATA COLLECTION AND ANALYSIS: Pairs of review authors independently selected studies, assessed risk of bias and extracted data. We pooled data where appropriate and used GRADE for assessing the certainty of evidence for each outcome. We prepared a brief economic commentary for one comparison.

MAIN RESULTS

We included 47 trials (3179 participants, mostly women and mainly aged 60 years or over) that tested one of 26 comparisons. Six comparisons were tested by 2 to 10 trials, the others by small single-centre trials only. Twelve studies evaluated non-surgical treatments, 10 compared surgical with non-surgical treatments, 23 compared two methods of surgery, and two tested timing of mobilisation after surgery. Most trials were at high risk of bias, due mainly to lack of blinding. We summarise the findings for four key comparisons below. Early (usually one week post injury) versus delayed (after three or more weeks) mobilisation for non-surgically-treated fractures Five trials (350 participants) made this comparison; however, the available data are very limited. Due to very low-certainty evidence from single trials, we are uncertain of the findings of better shoulder function at one year in the early mobilisation group, or the findings of little or no between-group difference in function at 3 or 24 months. Likewise, there is very low-certainty evidence of no important between-group difference in quality of life at one year. There was one reported death and five serious shoulder complications (1.9% of 259 participants), spread between the two groups, that would have required substantive treatment. Surgical versus non-surgical treatment Ten trials (717 participants) evaluated surgical intervention for displaced fractures (66% were three- or four-part fractures). There is high-certainty evidence of no clinically important difference between surgical and non-surgical treatment in patient-reported shoulder function at one year (standardised mean difference (SMD) 0.10, 95% confidence interval (CI) -0.07 to 0.27; 7 studies, 552 participants) and two years (SMD 0.06, 95% CI -0.13 to 0.25; 5 studies, 423 participants). There is moderate-certainty evidence of no clinically important between-group difference in patient-reported shoulder function at six months (SMD 0.17, 95% CI -0.04 to 0.38; 3 studies, 347 participants). There is high-certainty evidence of no clinically important between-group difference in quality of life at one year (EQ-5D (0: dead to 1: best quality): mean difference (MD) 0.01, 95% CI -0.02 to 0.04; 6 studies, 502 participants). There is low-certainty evidence of little between-group difference in mortality: one of the 31 deaths was explicitly linked with surgery (risk ratio (RR) 1.35, 95% CI 0.70 to 2.62; 8 studies, 646 participants). There is low-certainty evidence of a higher risk of additional surgery in the surgery group (RR 2.06, 95% CI 1.21 to 3.51; 9 studies, 667 participants). Based on an illustrative risk of 35 subsequent operations per 1000 non-surgically-treated patients, this indicates an extra 38 subsequent operations per 1000 surgically-treated patients (95% CI 8 to 94 more). Although there was low-certainty evidence of a higher overall risk of adverse events after surgery, the 95% CI also includes a slightly increased risk of adverse events after non-surgical treatment (RR 1.46, 95% CI 0.92 to 2.31; 3 studies, 391 participants). Open reduction and internal fixation with a locking plate versus a locking intramedullary nail Four trials (270 participants) evaluated surgical intervention for displaced fractures (63% were two-part fractures). There is low-certainty evidence of no clinically important between-group difference in shoulder function at one year (SMD 0.15, 95% CI -0.12 to 0.41; 4 studies, 227 participants), six months (Disability of the Arm, Shoulder, and Hand questionnaire (0 to 100: worst disability): MD -0.39, 95% CI -4.14 to 3.36; 3 studies, 174 participants), or two years (American Shoulder and Elbow Surgeons score (ASES) (0 to 100: best outcome): MD 3.06, 95% CI -0.05 to 6.17; 2 studies, 101 participants). There is very low-certainty evidence of no between-group difference in quality of life (1 study), and of little difference in adverse events (4 studies, 250 participants) and additional surgery (3 studies, 193 participants). Reverse total shoulder arthroplasty (RTSA) versus hemiarthroplasty There is very low-certainty evidence from two trials (161 participants with either three- or four-part fractures) of no or minimal between-group differences in self-reported shoulder function at one year (1 study) or at two to three years' follow-up (2 studies); or in quality of life at one year or at two or more years' follow-up (1 study). Function at six months was not reported. Of 10 deaths reported by one trial (99 participants), one appeared to be surgery-related. There is very low-certainty evidence of a lower risk of complications after RTSA (2 studies). Ten people (6.2% of 161 participants) had a reoperation; all eight cases in the hemiarthroplasty group received a RTSA (very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is high- or moderate-certainty evidence that, compared with non-surgical treatment, surgery does not result in a better outcome at one and two years after injury for people with displaced proximal humeral fractures. It may increase the need for subsequent surgery. The evidence is absent or insufficient for people aged under 60 years, high-energy trauma, two-part tuberosity fractures or less common fractures, such as fracture dislocations and articular surface fractures. There is insufficient evidence from randomised trials to inform the choices between different non-surgical, surgical or rehabilitation interventions for these fractures.

Ceramic bone graft substitute vs autograft in XLIF: a prospective randomized single-center evaluation of radiographic and clinical outcomes

Purpose of the Study

The objective of this prospective, parallel, randomized, single-center study is to evaluate the clinical success of a commercial ceramic bone graft substitute (CBGS) for autograft in eXtreme Lateral Interbody Fusion (XLIF) procedures. Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [Cristiano Magalhães], Last name [Menezes]. Author 2 Given name: [Gabriel Carvalho], Last name [Lacerda]. Author 5 Given name: [Erica Godinho], Last name [Menezes]. Also, kindly confirm the details in the metadata are correct.yes

Methods

Forty-five adult subjects were consecutively enrolled and randomized into a single-level XLIF procedure using either CBGS or iliac crest bone graft autograft (30 and 15 subjects, respectively). The primary outcome was fusion rate at 12, 18, and 24 months. Secondary outcomes were pain and disability measured by HRQOL questionnaires. Kindly check and confirm whether the corresponding author and his corresponding affiliations is correctly identified.yes

Results

The fusion rates for both CBGS and autograft groups at the 24-month follow-up were 96.4% and 100%, respectively. For the CBGS group, mean ODI, mean back pain, and mean worst leg pain significantly improved at the 24-month follow-up by 76.7% (39.9–9.3), 77.6% (7.3–1.6), and 81.3% (5.1–1.0), respectively. For the autograft group, mean ODI, mean back pain, and mean worst leg pain significantly improved during the same time period by 77.1% (35.9–8.2), 75.6% (6.1–1.5), and 86.0% (6.6–0.9), respectively (all time points between groups, p < 0.05).

Conclusion

The results of this prospective, randomized study support the use of CBGS as a standalone bone graft substitute for autograft in single-level XLIF surgery. The clinical performance and safety outcomes reported here are consistent with published evidence on CBGS. Improvements in patient-reported back pain, leg pain, and disability outcomes were comparable between the CBGS and autograft groups.

Therapeutic effect of autologous bone grafting with adjuvant bone morphogenetic protein on long bone nonunion: a systematic review and meta-analysis

BACKGROUND

The recombinant human bone morphogenetic protein (rhBMP) is a common graft substitute for treating cases of long bone nonunion. However, the feasibility of combining an autologous bone graft (ABG) with rhBMPs remains uncertain. Thus, this systematic review and meta-analysis aimed to evaluate the synergistic effect of ABG and rhBMPs on the healing of long bone nonunion.

METHODS

A systematic literature search was performed on PubMed, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. Two authors independently screened the studies, extracted data, and assessed the quality of the trials. Statistical analyses were performed using Stata 12.0.

RESULTS

Of the 202 citations, five studies involving a total of 394 cases met the eligibility criteria; thus, they were included in this study. The pooled data revealed no significant differences among the groups in terms of postoperative healing rate (risk ratio [RR] = 1.01, 95% confidence interval [CI] = 0.96-1.06, P = 0.744), healing time (standardised mean difference =  - 0.20, 95% CI = - 0.95-0.56, P = 0.610), and pain (RR = 1.44, 95% CI = 0.25-8.29, P = 0.681). The combination of ABG and rhBMPs resulted in good limb function (RR = 1.31, 95% CI = 1.04-1.66, P = 0.023).

CONCLUSIONS

The combination of ABG and rhBMPs did not result in the healing of long bone nonunion and pain reduction. Nevertheless, it conferred good limb function. Thus, the findings in this study are insufficient to support the use of rhBMPs as an adjuvant to ABG.

Clinical Reference Strategy for the Selection of Treatment Materials for Maxillofacial Bone Transplantation: A Systematic Review and Network Meta-Analysis

Bone graft materials have mixed effects of bone repair in the field of oral maxillofacial surgery. The qualitative analyses performed by previous studies imply that autogenous odontogenic materials and autogenous bone have similar effects on bone repair in clinical jaw bone transplantation. This retrospective systematic assessment and network meta-analysis aimed to analyze the best effect of clinical application of autogenous odontogenic materials and autogenous, allogeneic, and xenogeneic bone grafts in bone defect repair. A systematic review was performed by searching the PubMed, Cochrane Library, and other journal databases using selected keywords and Medical Subject Headings search terms. 10 Papers (n = 466) that met the inclusion criteria were selected. The assessment of heterogeneity did not reveal any overall statistical difference or heterogeneity (P = 0.051 > 0.05), whereas the comparison between autogenous and allogeneic bone grafts revealed local heterogeneity (P = 0.071 < 0.1). Risk of bias revealed nine unclear studies and one high-risk study. The overall consistency was good (P = 0.065 > 0.05), and the local inconsistency test did not reveal any inconsistency. The publication bias was good. The confidence regarding the ranking of bone graft materials after GRADE classification was moderate. The effects on bone repair in the descending order were as follows: autogenous odontogenic materials, xenogeneic bone, autogenous bone, and allogeneic bone. This result indicates that the autogenous odontogenic materials displayed stronger effects on bone repair compared to other bone graft materials. Autogenous odontogenic materials have broad development prospects in oral maxillofacial surgery.

Changes in Dynamic Postural Stability After ACL Reconstruction: Results Over 2 Years of Follow-up

Background:

The anterior cruciate ligament (ACL) is crucial for knee proprioception and postural stability. While ACL reconstruction (ACLR) and rehabilitation improve postural stability, the timing in improvement of dynamic postural stability after ACLR remains relatively unknown.

Purpose:

To evaluate changes in dynamic postural stability after ACLR out to 24 months postoperatively.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients undergoing ACLR were prospectively enrolled, and dynamic postural stability was assessed within 2 days before surgery, at 3-month intervals postoperatively to 18 months, then at 24 months. Measurements were made on a multidirectional platform tracking the patient’s center of mass based on pelvic motion. The amount of time the patient was able to stay on the platform was recorded, and a dynamic motion analysis score, reflecting the patient’s ability to maintain one’s center of mass, was generated overall and in 6 independent planes of motion.

Results:

A total of 44 patients with a mean age of 19.7 ± 6.2 years completed the study protocol. Overall mean dynamic postural stability improved significantly at 3, 6, 9, and 12 months after surgery, with continued improvement out to 24 months. Notable improvements occurred in medial/lateral and anterior/posterior stability from baseline to 6 months postoperatively, while internal/external rotation and flexion/extension stability declined initially after surgery from baseline to 3 months postoperatively before stabilizing to the end of the study period.

Conclusion:

Overall dynamic postural stability significantly improved up to 12 months after ACLR. Improvement in postural stability occurred primarily in the medial/lateral and anterior/posterior planes of motion, with initial decreases in the flexion/extension and internal/external rotational planes of motion.

Characterization of Induction and Targeting of Senescent Mesenchymal Stromal Cells

Mesenchymal stromal cells (MSCs) from older donors have limited potential for bone tissue formation compared with cells from younger donors, and cellular senescence has been postulated as an underlying cause. There is a critical need for methods to induce premature senescence to study this phenomenon efficiently and reproducibly. However, the field lacks consensus on the appropriate method to induce and characterize senescence. Moreover, we have a limited understanding of the effects of commonly used induction methods on senescent phenotype. To address this significant challenge, we assessed the effect of replicative, hydrogen peroxide, etoposide, and irradiation-induced senescence on human MSCs using a battery of senescent cell characteristics. All methods arrested proliferation and resulted in increased cell spreading compared with low passage controls. Etoposide and irradiation increased expression of senescence-related genes in MSCs at early time points, proinflammatory cytokine secretion, DNA damage, and production of senescence-associated β-galactosidase. We then evaluated the effect of fisetin, a flavonoid and candidate senolytic agent, to clear senescent cells and promote osteogenic differentiation of MSCs entrapped in gelatin methacryloyl (GelMA) hydrogels in vitro. When studying a mixture of nonsenescent and senescent MSCs, we did not observe decreases in senescent markers or increases in osteogenesis with fisetin treatment. However, the application of the same treatment toward a heterogeneous population of human bone marrow-derived cells entrapped in GelMA decreased senescent markers and increased osteogenesis after 14 days in culture. These results identify best practices for inducing prematurely senescent MSCs and motivate the need for further study of fisetin as a senolytic agent. Impact Statement The accumulation of senescent cells within the body has detrimental effects on tissue homeostasis. To study the role of senescent cells on tissue repair and regeneration, there is a need for effective means to induce premature cell senescence. Herein, we characterized the influence of common stressors to induce premature senescence in human mesenchymal stromal cells (MSCs). Irradiation of MSCs resulted in a phenotype most similar to quiescent, high-passage cells. These studies establish key biomarkers for evaluation when studying senescent cells in vitro.

Tibial cancellous bone auto-grafting for medial open-wedge high tibial osteotomy: bone void filling with tissue harvested from osteotomized medullary canal

The aim of the study was to evaluate the clinical and radiological outcomes in a series of patients undergoing open wedge high tibial osteotomy (OWHTO) using tibial cancellous autograft harvested from the osteotomized medullary canal which is not reported in the literature before. Patients with medial compartment osteoarthritis were treated with OWHTO and tibial cancellous auto- grafting performed from the osteotomized medullary canal and used for bone void filling. Seventy patients (seventy-two knees) treated with OWHTO were analyzed. All patients started partial weight-bearing with crutches the day after surgery and full-weight bearing eight weeks after surgery, according to radiological evaluation. Fifty-seven women and 13 men with a mean age of 54.2±8.1 years were evaluated in this study. The mean correction angle was 8.4±2.5° (range: 5.3°-14.3°). The osteotomy sites of all patients were grafted with tibial cancellous autografts. In all patients bony union was detected after surgery. No implant failures or major complications were en- countered. Clinical and radiological findings revealed that bone void filling with the harvested autograft from the osteotomized medullary canal may be a satisfactory and reliable option in OWHTO.

Nonlinear micro finite element models based on digital volume correlation measurements predict early microdamage in newly formed bone

Bone regeneration in critical-sized defects is a clinical challenge, with biomaterials under constant development aiming at enhancing the natural bone healing process. The delivery of bone morphogenetic proteins (BMPs) in appropriate carriers represents a promising strategy for bone defect treatment but optimisation of the spatial-temporal release is still needed for the regeneration of bone with biological, structural, and mechanical properties comparable to the native tissue. Nonlinear micro finite element (μFE) models can address some of these challenges by providing a tool able to predict the biomechanical strength and microdamage onset in newly formed bone when subjected to physiological or supraphysiological loads. Yet, these models need to be validated against experimental data. In this study, experimental local displacements in newly formed bone induced by osteoinductive biomaterials subjected to in situ X-ray computed tomography compression in the apparent elastic regime and measured using digital volume correlation (DVC) were used to validate μFE models. Displacement predictions from homogeneous linear μFE models were highly correlated to DVC-measured local displacements, while tissue heterogeneity capturing mineralisation differences showed negligible effects. Nonlinear μFE models improved the correlation and showed that tissue microdamage occurs at low apparent strains. Microdamage seemed to occur next to large cavities or in biomaterial-induced thin trabeculae, independent of the mineralisation. While localisation of plastic strain accumulation was similar, the amount of damage accumulated in these locations was slightly higher when including material heterogeneity. These results demonstrate the ability of the nonlinear μFE model to capture local microdamage in newly formed bone tissue and can be exploited to improve the current understanding of healing bone and mechanical competence. This will ultimately aid the development of BMPs delivery systems for bone defect treatment able to regenerate bone with optimal biological, mechanical, and structural properties.

Surgical Fixation of Three- and Four-Part Proximal Humeral Fractures Using the Proximal Humeral Interlocking System Plate

Introduction

The management of proximal humeral fractures ranges greatly from conservative management to surgical treatment. For those fractures requiring surgical treatment, internal fixation is the primary method. The aim of internal fixation is to achieve rigid fracture fixation until union occurs, return of shoulder range of motion, and minimise intra-and postoperative complications. The aim of this study was to evaluate the results of the Proximal Humeral Interlocking System Plate (PHILOS) used for the treatment of three-and four-part proximal humeral fractures.

Materials and methods

This study included 30 patients with a mean age of 54 years (range 20-80 years). Results were checked post-operatively with standard radiographs and clinical evaluation according to the Constant-Murley shoulder score. All patients were followed up for 12 months.

Results

Union was achieved in all patients with a mean neck/shaft angle of 130° (range 108°-150°). The mean Constant-Murley score at the final follow-up was 82.28 (range 67-96) correlating with good results. No patients developed an intraoperative or postoperative vascular injury, wound complications, or avascular necrosis of the humeral head.

Conclusion

Our study has shown that the surgical treatment of three- and four-part proximal humeral fractures with the use of the PHILOS plate leads to a good functional outcome. It has also demonstrated the PHILOS plate and is an effective system for fracture stabilisation provided the correct surgical technique is used with awareness of potential hardware complications.

3D printing applications in spine surgery: an evidence-based assessment toward personalized patient care

PURPOSE

Spine surgery entails a wide spectrum of complicated pathologies. Over the years, numerous assistive tools have been introduced to the modern neurosurgeon's armamentarium including neuronavigation and visualization technologies. In this review, we aimed to summarize the available data on 3D printing applications in spine surgery as well as an assessment of the future implications of 3D printing.

METHODS

We performed a comprehensive review of the literature on 3D printing applications in spine surgery.

RESULTS

Over the past decade, 3D printing and additive manufacturing applications, which allow for increased precision and customizability, have gained significant traction, particularly spine surgery. 3D printing applications in spine surgery were initially limited to preoperative visualization, as 3D printing had been primarily used to produce preoperative models of patient-specific deformities or spinal tumors. More recently, 3D printing has been used intraoperatively in the form of 3D customizable implants and personalized screw guides.

CONCLUSIONS

Despite promising preliminary results, the applications of 3D printing are so recent that the available data regarding these new technologies in spine surgery remains scarce, especially data related to long-term outcomes.

Cell-controlled dynamic surfaces for skeletal stem cell growth and differentiation

Skeletal stem cells (SSCs, or mesenchymal stromal cells typically referred to as mesenchymal stem cells from the bone marrow) are a dynamic progenitor population that can enter quiescence, self-renew or differentiate depending on regenerative demand and cues from their niche environment. However, ex vivo, in culture, they are grown typically on hard polystyrene surfaces, and this leads to rapid loss of the SSC phenotype. While materials are being developed that can control SSC growth and differentiation, very few examples of dynamic interfaces that reflect the plastic nature of the stem cells have, to date, been developed. Achieving such interfaces is challenging because of competing needs: growing SSCs require lower cell adhesion and intracellular tension while differentiation to, for example, bone-forming osteoblasts requires increased adhesion and intracellular tension. We previously reported a dynamic interface where the cell adhesion tripeptide arginine-glycine-aspartic acid (RGD) was presented to the cells upon activation by user-added elastase that cleaved a bulky blocking group hiding RGD from the cells. This allowed for a growth phase while the blocking group was in place and the cells could only form smaller adhesions, followed by an osteoblast differentiation phase that was induced after elastase was added which triggered exposure of RGD and subsequent cell adhesion and contraction. Here, we aimed to develop an autonomous system where the surface is activated according to the need of the cell by using matrix metalloprotease (MMP) cleavable peptide sequences to remove the blocking group with the hypothesis that the SSCs would produce higher levels of MMP as the cells reached confluence. The current studies demonstrate that SSCs produce active MMP-2 that can cleave functional groups on a surface. We also demonstrate that SSCs can grow on the uncleaved surface and, with time, produce osteogenic marker proteins on the MMP-responsive surface. These studies demonstrate the concept for cell-controlled surfaces that can modulate adhesion and phenotype with significant implications for stem cell phenotype modulation.

Bioinspired Surface Functionalization of Poly(ether ether ketone) for Enhancing Osteogenesis and Bacterial Resistance

In orthopedics, developing functionalized biomaterials to enhance osteogenesis and bacterial resistance is crucial. Although poly(ether ether ketone) (PEEK) is regarded as an important engineering plastic for biomedical material with excellent mechanical properties and biocompatibility, its biological inertness has greatly compromised its application in biomedical engineering. Inspired by the catecholamine chemistry of mussels, we propose a universal and versatile approach for enhancing the osteogenesis and antibacterial performances of PEEK based on surface functionalization of polydopamine-modified nanohydroxyapatite and lysozyme simultaneously. The characterizations of surface morphology and elemental composition revealed that the composite coating was successfully added to the PEEK surface. Additionally, the in vitro cell experiment and biomineralization assay indicated that the composite coating-modified PEEK was biocompatible with significantly improved bioactivity to promote osteogenesis and biomineralization compared with the untreated PEEK. Furthermore, the antibacterial test demonstrated that the composite coating had a strongly destructive effect on two bacteria (Staphylococcus aureus and Escherichia coli) with antibacterial ratios of 98.7% and 96.1%, respectively. In summary, the bioinspired method for surface functionalization can enhance the osteogenesis and bacterial resistance of biomedical materials, which may represent a potential approach for designing functionalized implants in orthopedics.