The role of orthobiologics in foot and ankle surgery: Allogenic bone grafts and bone graft substitutes

Locally obtained autologous bone grafts are effective for achieving arthrodesis while managing foot and ankle charcot's neuroarthropathy: short to mid-term results from a specialized north African foot and ankle surgery unit

PURPOSE

We aimed to report the union rate after only utilizing a locally obtained autologous bone graft while correcting the deformity and performing joint arthrodesis in patients with foot and ankle Charcot neuropathy (CN) and to report on the radiographic, functional, complications incidence outcomes at a minimum of two years of follow up.

METHODS

We included 24 patients having a mean age of 55.4 ± 10.1 years diagnosed with CN of the foot, ankle, or both. Seven (29.2%) cases were classified as Brodsky type 1, 11 (45.8%) as type 3 A, and six (25%) were type 4. Hindfoot and Midfoot bi-columnar arthrodesis was performed in 70.8% and 29.2% of the patients, respectively. Eight (33.3%) cases had preoperative ulcers. Functional outcomes were evaluated using a modified AOFAS score. Arthrodesis site union was assessed clinically and radiographically. All patients were available for a mean follow up of 35.7 ± 9.5 (24-54) months.

RESULTS

Arthrodesis site union was achieved in 23 (95.8%) cases after a mean of 4 ± 1.7 (2-7.5) months. The mean modified AOFAS score was 72.4 ± 10.41 (46-83) points; 79.2% achieved excellent and good scores. Ulcers healed in 87.5% of the patients. Twenty-two (91.7%) patients were satisfied with their functional results. Infection incidence was 12.5%, and no patients required revision or amputation.

CONCLUSION

Foot and ankle Charcot neuroarthropathy deformity correction by arthrodesis of the affected joint as a salvage management option resulted in acceptable clinical and radiological outcomes. To enhance the local environment for arthrodesis consolidation, locally obtained autografts led to higher union rates and avoided the drawbacks of using other graft types.

Comparative Studies of Bone Graft and Orthobiologics for Foot Ankle Arthrodesis: A Critical Review

Graft materials available to supplement hindfoot and ankle arthrodesis procedures include autologous (autograft) or allogeneic bone graft (allograft) but also bone graft substitutes such as demineralized bone matrix, calcium sulfate, calcium phosphate, and tricalcium phosphate/hydroxyapatite. In addition, biologic agents, such as recombinant human bone morphogenetic protein-2 or recombinant human platelet derived growth factor-BB (rhPDGF-BB), and preparations, including platelet-rich plasma or concentrated bone marrow aspirate, have been used to facilitate bone healing in ankle or hindfoot arthrodesis. The purpose of this review was to summarize the available clinical evidence surrounding the utilization and efficacy of the above materials and biological agents in ankle or hindfoot arthrodesis procedures, with emphasis on the quality of the existing evidence to facilitate clinical decision making.

Traumatic Fracture Treatment: Calcium Phosphate Bone Substitute Case-Control Study in Humerus, Radius, Tibia Fractures-Assessing Efficacy and Recovery Outcomes

To date, insufficient investigation has been carried out on the biocompatibility of synthetic bioactive bone substitute materials after traumatically induced bone fractures in clinical conditions. This study encompasses the safety, resorption, healing process, and complications of surgical treatment. Our current hypothesis posits that calcium phosphate-based bone substitutes could improve bone healing. In this retrospective case-control study, over 290 patients who underwent surgical treatment for acute fractures were examined. Bone defects were augmented with calcium phosphate-based bone substitute material (CP) in comparison to with empty defect treatment (ED) between 2011 and 2018. A novel scoring system for fracture healing was introduced to assess bone healing in up to six radiological follow-up examinations. Furthermore, demographic data, concomitant diseases, and complications were subjected to analysis. Data analysis disclosed significantly fewer postoperative complications in the CP group relative to the ED group (p < 0.001). The CP group revealed decreased risks of experiencing complications (p < 0.001), arthrosis (p = 0.01), and neurological diseases (p < 0.001). The fracture edge, the fracture gap, and the articular surface were definably enhanced. Osteosynthesis and general bone density demonstrated similarity (p > 0.05). Subgroup analysis focusing on patients aged 64 years and older revealed a diminished complication incidence within the CP group (p = 0.025). Notably, the application of CP bone substitute materials showed discernible benefits in geriatric patients, evident by decreased rates of pseudarthrosis (p = 0.059). Intermediate follow-up evaluations disclosed marked enhancements in fracture gap, edge, and articular surface conditions through the utilization of CP-based substitutes (p < 0.05). In conclusion, calcium phosphate-based bone substitute materials assert their clinical integrity by demonstrating safety in clinical applications. They substantiate an accelerated early osseous healing trajectory while concurrently decreasing the severity of complications within the bone substitute cohort. In vivo advantages were demonstrated for CP bone graft substitutes.

A retrospective review of recombinant human platelet-derived growth factor with beta-tricalcium phosphate bone graft substitute use in hindfoot and/or ankle arthrodesis

Background

Nonunion following foot and ankle arthrodesis can cause chronic pain and disability, poor patient satisfaction, and increased healthcare costs. Nonunion rates are reported in 10%-12% of primary foot and/or ankle arthrodesis procedures, with significantly greater rates among patients with high-risk factors such as smoking, diabetes, obesity, or Charcot neuroarthropathy. Recombinant human platelet-derived growth factor BB-homodimer with beta-tricalcium phosphate (rhPDGF-BB/β-TCP) is a bone graft substitute that has demonstrated efficacy in foot and ankle fusion rates that are comparable to autograft.

Methods

Charts and radiographs were retrospectively reviewed on consecutive adult patients undergoing talonavicular, calcaneal-cuboid, subtalar, and/or ankle arthrodesis utilizing rhPDGF-BB/β-TCP bone graft substitute. The primary outcome measures were rate of and mean time to fusion, mean time to return to function, and incidence of adverse events.

Results

This study reviewed133 patients who underwent 209 hindfoot and/or ankle joint arthrodesis procedures with a mean follow-up 20.34 ± 11.05 months. The overall fusion rate was 92.82% (194/209 joints) with a mean time to fusion of 13.14 ± 2.52 weeks and return to function of 16.56 ± 3.26 weeks. Overall, there were 7 (5.26%) patients who experienced an adverse event (AE) with 15 (7.18%) joints experiencing a nonunion.

Conclusion

Fusion rates with rhPDGF-BB/β-TCP bone grafting material compared favorably to autograft controls when used in hindfoot and/or ankle arthrodesis. No AEwas related to rhPDGF-BB/β-TCP. This study suggests that using rhPDGF-BB/β-TCP is effective in hindfoot and/or ankle arthrodesis, even among patients with comorbidities who are at a higher risk of developing a nonunion.

Level of clinical evidence

3.

A, Ajoy SM. Fresh Fractures: A New Indication for Use of Bone Allografts-A 10-Year Data Analysis

Background

Tissue banking includes the process starting from procurement to the distribution and usage of allograft tissues. The use of bone bank in orthopaedics is not widely seen. Our objective is to describe the 10-year allograft donor and recipient data from a fully functioning tissue bank in India, analyse the types of grafts used, indications and demand for various grafts. This will show the need for a tissue bank in a tertiary care orthopaedic setup.

Methods

Analysis of donor and recipient data for allografts of a tissue bank in an Indian tertiary care setup was done from 2012 to 2022. The number of grafts procured and used were analysed. The recipient and donor sites were also analysed.

Results

In 10 years, the tissue bank provided 2776 grafts and received 1962 donations. Slices procured after total knee replacements were the most commonly used allografts (28.03%). Acute fracture with bone loss or severe comminution (23.11%) being the most common indication of bone grafting was a major result of our study. Among these, proximal tibia (27.79%) was the most frequent recipient site. Tissue bank has also served patients in neurosurgery, ophthalmology, oromaxillofacial surgery, otorhinolaryngology, urology and wound care.

Conclusion

A tissue bank is a useful setup in tertiary care orthopaedic hospitals. Allografts were most widely used for acute trauma management. Allografts provide large graft quantity and reduce surgical time. Hence a tissue bank is not only an asset to the establishment but also to the surrounding hospitals, to which the grafts can be supplied.

Efficacy and Safety of Beta-Tricalcium Phosphate/Polylactic-Co-Glycolic Acid for Implantation of Bone Defects

INTRODUCTION

Bone defects are often observed after surgery for fractures and bone tumors. Their treatment is technically difficult and sometimes results in negative clinical and economic outcomes. To repair bone defects, a bone graft is implanted by selecting a transplant material from an autologous or artificial bone. Each method has its advantages and disadvantages. Compared to the gold standard of autologous bone graft, bone graft substitutes are not limited by the amount of harvested graft and avoid complications at the donor site. ORB-03 is a new cotton-like bone graft substitute composed of beta-tricalcium phosphate (β-TCP) and a bioabsorbable polymer, polylactic-co-glycolic acid (PLGA). ORB-03 is easy to mold and can fill various bone defect shapes, and its three-dimensional microfiber scaffold can enhance the differentiation of osteoblasts and promote osteogenesis. We investigated the efficacy, ease of handling, and safety of ORB-03 as a bone graft substitute. A multicenter, open-label, single-group study was conducted at six institutions.

METHODS

Between July 2018 and August 2019, 60 patients with bone defects caused by fracture, benign tumors, or an iliac donor site from bone harvesting were enrolled in this study; 54 patients were finally included for the safety analysis and 48 patients for the image analysis. During surgery, ORB-03 was mixed with the patient's blood and molded into a bone defect. To evaluate the efficacy of ORB-03, radiography and computed tomography (CT) were performed at intervals until 24 weeks after surgery.

RESULTS

The effective rate and its accurate bilateral 95% confidence interval (CI) were calculated based on the efficacy criteria at 24 weeks postoperatively. The ease with which ORB-03 could be handled in surgery was evaluated. Adverse events that occurred after surgery were evaluated, and those associated with ORB-03 were examined. Bone fusion was good in all cases, and the radiography and CT effective rates were 100.0% and 91.5%, respectively. Handling was easy in all cases. There were four adverse events, none of which were clinically problematic.

CONCLUSIONS

ORB-03 was found to be easy to handle, safe, and effective as a bone graft substitute for bone defects.

Evaluation of Adjuvant Antibiotic Loaded Injectable Bio-Composite Material in Diabetic Foot Osteomyelitis and Charcot Foot Reconstruction

The management of diabetic foot osteomyelitis (DFO) is extremely challenging with high amputation rates reported alongside a five-year mortality risk of more than fifty percent. We describe our experience in using adjuvant antibiotic-loaded bio-composite material (Cerament) in the surgical management of DFO and infected Charcot foot reconstruction. We undertook a retrospective evaluation of 53 consecutive patients (54 feet) who underwent Gentamicin or Vancomycin-loaded Cerament application during surgery. The feet were categorised into two groups: Group 1, with infected ulcer and DFO, managed with radical debridement only (n = 17), and Group 2, requiring reconstruction surgery for infected and deformed Charcot foot. Group 2 was further subdivided into 2a, with feet previously cleared of infection and undergoing a single-stage reconstruction (n = 19), and 2b, with feet having an active infection managed with a two-stage reconstruction (n = 18). The mean age was 56 years (27-83) and 59% (31/53) were males. The mean BMI was 30.2 kg/m² (20.8-45.5). Foot ulcers were present in 69% (37/54) feet. At a mean follow-up of 30 months (12-98), there were two patients lost to follow up and the mortality rate was 11% (n = 5). The mean duration of post-operative systemic antibiotic administration was 20 days (4-42). Thirteen out of fifteen feet (87%) in group 1 achieved complete eradication of infection. There was a 100% primary ulcer resolution, 100% limb salvage and 76% bony union rate within Group 2. However, five patients, all in group 2, required reoperations due to problems with bone union. The use of antibiotic-loaded Cerament resulted in a high proportion of patients achieving infection clearance, functional limb salvage and decrease in the duration of postoperative antibiotic therapy. Larger, preferably randomised, studies are required to further validate these observations.

Orthobiologic Use in Sports Injuries

Orthobiologics have gained much popularity in recent years but there has not been a large amount of clinical evidence to support their use. In the limited research that has been published, they have been shown to be effective and safe. They can assist in earlier return to activity with the avoidance of surgery. They can also augment current surgical practice to aid in healing and return to sport with few complications. With new medical innovation, there is unfortunately a higher cost for these products. The use of orthobiologics will only grow and so will the need for high-level clinical evidence.

General Considerations About Foot and Ankle Arthrodesis. Any Way to Improve Our Results?

Nonunion and adjacent joint osteoarthritis (OA) are known complications after a fusion procedure, and foot and ankle surgeons are commonly exposed to such disabling complications. Determining who is at risk of developing nonunion is essential to reducing nonunion rates and improving patient outcomes. Several evidenced-based modifiable risk factors related to adverse outcomes after foot and ankle arthrodesis have been identified. Patient-related risk factors that can be improved before surgery include smoking cessation, good diabetic control (HbAc1 <7%) and vitamin D supplementation. Intraoperatively, using less invasive techniques, avoiding joint preparation with power tools, using bone grafts or orthobiologics in more complex cases, high-risk patients, nonunion revision surgeries, and filling in bone voids at the arthrodesis site should be considered. Postoperatively, pain management with NSAIDs should be limited to a short period (<2 weeks) and avoided in high-risk patients. Furthermore, early postoperative weight-bearing has shown to be beneficial, and it does not seem to increase postoperative complications. The incidence of surrounding joint OA after foot and ankle fusion seems to increase progressively with time. Owing to its progression and high probability of being symptomatic, patients must be informed consequently, as they may require additional joint fusions, resulting in further loss of ankle/foot motion. In patients with symptomatic adjacent joint OA and unsatisfactory results after an ankle arthrodesis, conversion to total ankle arthroplasty (TAA) has become a potential option in managing these complex and challenging situations.

Does Demineralized Bone Matrix Affect the Nonunion Rate in Arthroscopic Ankle Arthrodesis?

Demineralized bone matrix (DBM) has been shown to have positive effects on union rates in many orthopedic subspecialties; however, minimal evidence exists about bone graft substitutes in foot and ankle surgery. The purpose of this study is to compare nonunion rates in arthroscopic ankle arthrodesis in patients receiving DBM with those without. We hypothesized DBM to be associated with a decreased risk of nonunion. This retrospective review includes 516 consecutive ankle arthrodesis cases from March 2002 to May 2016. Of these, 58 ankles (56 patients) that underwent primary arthroscopic ankle arthrodesis met the inclusion criteria, and 31 of these ankles received DBM, while 27 did not. Nonunion was assessed by clinical examination and routine postoperative radiographs. If nonunion was suspected, a computed tomography (CT) scan was performed. The primary outcome measure was nonunion rate. Secondary outcome measures included wound complications, return to operating room (OR), and rate of postoperative deep vein thrombosis (DVT) or pulmonary embolism (PE). From the study cases, 58 were available for final follow-up. The average age was 55.9 years (±17.4), and mean follow-up was 43.0 months (range 6.3–119.4). There was no difference in nonunion rate in patients who received DBM (4/31, 12.9%) versus those who did not (4/27, 14.8%) (p = 0.83). Similarly, when comparing the two groups, there were no statistically significant differences in superficial wound complications (6.5% vs. 3.7%, p = 1.0) or rate of return to OR (29% or 0.037/person-years vs. 37% or 0.099/person-years; p = 0.20). No major complications including deep wound infections, DVTs, or PEs occurred. This is the largest study to directly compare nonunion rates and complications for patients receiving DBM versus those who did not in primary arthroscopic ankle arthrodesis. No significant association was found between DBM usage and risk of nonunion, wound complications, return to OR, or postoperative DVT or PE development.

Surgical Management of Jones Fractures in Athletes: Orthobiologic Augmentation: A Systematic Review and Meta-analysis of 718 Fractures

BACKGROUND

The use of orthobiologics is expanding. However, the use of orthobiologic augmentation in primary fracture fixation surgery remains limited. Primary fracture fixation of the fifth metatarsal (Jones) in athletes is one of the rare situations where primary orthobiologic augmentation has been advocated.

PURPOSE

To determine the effect of orthobiologic augmentation on the outcome of surgically managed Jones fractures in athletes.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, 2 independent team members searched several databases including PubMed, MEDLINE, Embase, Google Scholar, Web of Science, Cochrane Library, and ClinicalTrials.gov through March 2021 to identify studies reporting on surgically managed Jones fractures of the fifth metatarsal exclusively in athletes. The primary outcomes were the return to play (RTP) rate and time to RTP, whereas the secondary outcomes were time to union, union rate, and refractures. Data were presented by type of treatment (biologically augmented fixation or fixation alone).

RESULTS

In the biologically augmented fixation group, successful RTP was reported in 195 (98.98%) of 197 fractures (odds ratio [OR], 97.5%; 95% CI, 95.8%-100%; I² = 0), with a mean time to RTP of 10.3 weeks (95% CI, 9.5-11.1 weeks; I² = 99%). In the group that received fixation without biological augmentation, successful RTP was reported in 516 (99.04%) of 521 fractures (OR, 98.7%; 95% CI, 97.8%-99.7%; I² = 0], with a mean time to RTP of 9.7 weeks (95% CI, 7.84-11.53 weeks; I² = 98.64%]. In the biologically augmented fixation group, fracture union was achieved in 194 (98.48%) of 197 fractures (OR, 97.6%; 95% CI, 95.5%-99.7%; I² = 0%), with a mean time to fracture union of 9.28 weeks (95% CI, 7.23-11.34 weeks; I² = 98.18%). In the group that received fixation without biological augmentation, fracture union was achieved in 407 (93.78%) of 434 fractures (OR, 97.4%; 95% CI, 96%-98.9%; I² = 0%), with a mean time to fracture union of 8.57 weeks (95% CI, 6.82-10.32 weeks; I² = 98.81%).

CONCLUSION

Orthobiologically augmented surgical fixation of Jones fractures in athletes is becoming increasingly common, despite the lack of comparative studies to support this practice. Biologically augmented fixation of Jones fractures results in higher fracture union rates than fixation alone but similar rates of RTP and time to RTP. Although the current evidence recommends primary surgical fixation for the management of Jones fractures in athletes, further high quality comparative studies are required to establish the indication for orthobiologic augmentation.

Role of Implantable Drug Delivery Devices with Dual Platform Capabilities in the Prevention and Treatment of Bacterial Osteomyelitis

As medicine advances and physicians are able to provide patients with innovative solutions, including placement of temporary or permanent medical devices that drastically improve quality of life of the patient, there is the persistent, recurring problem of chronic bacterial infection, including osteomyelitis. Osteomyelitis can manifest as a result of traumatic or contaminated wounds or implant-associated infections. This bacterial infection can persist as a result of inadequate treatment regimens or the presence of biofilm on implanted medical devices. One strategy to mitigate these concerns is the use of implantable medical devices that simultaneously act as local drug delivery devices (DDDs). This classification of device has the potential to prevent or aid in clearing chronic bacterial infection by delivering effective doses of antibiotics to the area of interest and can be engineered to simultaneously aid in tissue regeneration. This review will provide a background on bacterial infection and current therapies as well as current and prospective implantable DDDs, with a particular emphasis on local DDDs to combat bacterial osteomyelitis.

Unraveling of Advances in 3D-Printed Polymer-Based Bone Scaffolds

The repair of large-area irregular bone defects is one of the complex problems in orthopedic clinical treatment. The bone repair scaffolds currently studied include electrospun membrane, hydrogel, bone cement, 3D printed bone tissue scaffolds, etc., among which 3D printed polymer-based scaffolds Bone scaffolds are the most promising for clinical applications. This is because 3D printing is modeled based on the im-aging results of actual bone defects so that the printed scaffolds can perfectly fit the bone defect, and the printed components can be adjusted to promote Osteogenesis. This review introduces a variety of 3D printing technologies and bone healing processes, reviews previous studies on the characteristics of commonly used natural or synthetic polymers, and clinical applications of 3D printed bone tissue scaffolds, analyzes and elaborates the characteristics of ideal bone tissue scaffolds, from t he progress of 3D printing bone tissue scaffolds were summarized in many aspects. The challenges and potential prospects in this direction were discussed.

Decellularised human bone allograft from different anatomical sites as a basis for functionally stratified repair material for bone defects

Tissue engineered bone solutions aim to overcome the limitations of autologous and allogeneic grafts. Decellularised tissues are produced by washing cellular components from human or animal tissue to produce an immunologically safe and biocompatible scaffold, capable of integration following implantation. A decellularisation procedure utilising low concentration sodium dodecyl sulphate (0.1% w/v) was applied to trabecular bone from human femoral heads (FH) and tibial plateaus (TP). Biological (histology, DNA quantification), biomechanical (compression testing) and structural (μCT) comparisons were made between decellularised and unprocessed cellular tissue. Total DNA levels of decellularised FH and TP bone were below 50 ng mg^-1 dry tissue weight and nuclear material was removed. No differences were found between cellular and decellularised bone, from each anatomical region, for all the biomechanical and structural parameters investigated. Differences were found between cellular FH and TP and between decellularised FH and TP. Decellularised FH had a higher ultimate compressive stress, Young's modulus and 0.2% proof stress than decellularised TP (p = 0.001, 0.002, 0.001, Mann Whitney U test, MWU). The mineral density of cellular and decellularised TP bone was significantly greater than cellular and decellularised FH bone respectively (cellular: p = 0.001, decellularised: p < 0.001, MWU). The bone volume fraction and trabecular thickness of cellular and decellularised FH bone were significantly greater than cellular and decellularised TP bone respectively (cellular: p = 0.001, 0.005; decellularised: p < 0.001, <0.001, MWU). Characterisation of decellularised trabecular bone from different anatomical regions offers the possibility of product stratification, allowing selection of biomechanical properties to match particular anatomical regions undergoing bone graft procedures.

A Multicenter, Retrospective, Case Series of Patients With Charcot Neuroarthropathy Deformities Undergoing Arthrodesis Utilizing Recombinant Human Platelet-derived Growth Factor With Beta-Tricalcium Phosphate

Charcot neuroarthropathy has traditionally been treated using both nonsurgical and surgical strategies. Recently, orthobiologics have been used to promote arthrodesis in Charcot reconstructions, obviating the need for bone graft in some cases. Recombinant human platelet-derived growth factor BB homodimer (rhPDGF-BB) in combination with beta-tricalcium phosphate scaffold (β-TCP) is a bone graft substitute shown to have comparable efficacy to autograft in incidence of foot and ankle fusion. This multicenter, consecutive case series analyzed patients undergoing Charcot reconstructions utilizing rhPDGF-BB/β-TCP for joint fusion. In this cohort, 98 patients (62.24% male) with a mean age of 62.82 ± 10.28 years (range 40-87) had a fusion incidence of 217 of 223 joints (97.31%) with a mean time to fusion of 13.09 ± 4.87 weeks (range 6-30). There were 6 nonunions in the patient population. Fusion was defined as ≥50% osseous bridging based on computed tomography and/or radiographic consolidation, in addition to clinical findings. With an overall complication rate of 26.53% (26/98), adverse events occurring in more than 1 patient limb included hardware failures (n = 7, 7.14%), infection (n = 4, 4.08%), wound dehiscence (n = 4, 4.08%), amputation (n = 3, 3.06%), and death (n = 2, 2.04%). There were no adverse events related to the grafting material. From this review, we found rhPDGF-BB/β-TCP to be a safe and effective graft material that can be considered a viable alternative to autograft, even in high-risk patients such as those with Charcot neuroarthropathy.

Efficacy of calcium phosphate cementing in the surgical treatment of Sanders Type II and III calcaneal fractures using screw fixation with sinus tarsi approach

OBJECTIVE

This study aimed to determine the effectiveness of calcium phosphate cementing in the surgical treatment of Sanders type II and III calcaneal fractures using screw fixation with sinus tarsi approach.

METHODS

In this retrospective study, 85 feet of 84 patients (74 males, 10 females; mean age 43 [17-61] years) in whom screw fixation was performed using the sinus tarsi approach for Sanders type II or III calcaneal fractures were included. The mean follow-up was 28 (14-39) months. Patients were categorized into 2 groups on the basis of whether calcium phosphate cement (CPC) was used. Group 1 had 37 patients with CPC (38 calcaneal fractures) and group 2 had 47 patients without CPC (47 calcaneal fractures). In the clinical assessment, the American Orthopedic Foot Ankle Society (AOFAS) hind foot score and the Maryland Foot Score (MFS) were used at the final follow-up. In the radiological assessment, Bohler's angle on plain radiograph and posterior facet step-off on computed tomography were measured pre-and postoperatively.

RESULTS

At the final follow-up, the mean Bohler's angle was 26.2° (20°-33°) in group 1 and 26° (17°-30°) in group 2 (P = 0.85). The mean posterior facet step-off was 1.6 (0-5) mm in group 1 and 1.5 (0-5) mm in group 2 (P = 0.85). The mean AOFAS score was 83.8 (59-100) in group 1 and 85.8 (60-100) in group 2 (P = 0.5). The mean MFS was 86.3 (66-100) in group 1 and 87.7 (66-100) in group 2 (P = 0.62).

CONCLUSION

Evidence from this study have shown that CPC may have no significant effect on clinical and radiological outcomes in the surgical treatment of Sanders type II and III calcaneal fractures using screw fixation with sinus tarsi approach.

Antibiotic loaded β-tricalcium phosphate/calcium sulfate for antimicrobial potency, prevention and killing efficacy of Pseudomonas aeruginosa and Staphylococcus aureus biofilms

This study investigated the efficacy of a biphasic synthetic β-tricalcium phosphate/calcium sulfate (β-TCP/CS) bone graft substitute for compatibility with vancomycin (V) in combination with tobramycin (T) or gentamicin (G) evidenced by the duration of potency and the prevention and killing efficacies of P. aeruginosa (PAO1) and S. aureus (SAP231) biofilms in in vitro assays. Antibiotic loaded β-TCP/CS beads were compared with antibiotic loaded beads formed from a well characterized synthetic calcium sulfate (CS) bone void filler. β-TCP/CS antibiotic loaded showed antimicrobial potency against PAO1 in a repeated Kirby-Bauer like zone of inhibition assay for 6 days compared to 8 days for CS. However, both bead types showed potency against SAP231 for 40 days. Both formulations loaded with V + T completely prevented biofilm formation (CFU below detection limits) for the 3 days of the experiment with daily fresh inoculum challenges (P < 0.001). In addition, both antibiotic loaded materials and antibiotic combinations significantly reduced the bioburden of pre-grown biofilms by between 3 and 5 logs (P < 0.001) with V + G performing slightly better against PAO1 than V + T. Our data, combined with previous data on osteogenesis suggest that antibiotic loaded β-TCP/CS may have potential to stimulate osteogenesis through acting as a scaffold as well as simultaneously protecting against biofilm infection. Future in vivo experiments and clinical investigations are warranted to more comprehensively evaluate the use of β-TCP/CS in the management of orthopaedic infections.

Subchondroplasty of the Ankle and Hindfoot for Treatment of Osteochondral Lesions and Stress Fractures: Initial Imaging Experience

Objective:To describe the imaging findings of patients treated with subchondroplasty (SCP) of the ankle and hindfoot. Materials and Methods: Eighteen patients (10 men, 8 women; age mean 43.1 years [range 20.1-67.7 years]) underwent ankle and hindfoot SCP at a single center over a 14-month period. Imaging data were reviewed retrospectively by 2 radiologists by consensus interpretation, including preoperative radiography (18), computed tomography (CT) (11), and magnetic resonance imaging (MRI) (13) and postoperative radiography (10), CT (4), and MRI (6). Follow-up imaging was acquired 1 month to 1.6 years following SCP. Results: Indications for SCP included symptomatic bone marrow lesions (BMLs) secondary to an osteochondral lesion (OCL) (16/18) or stress fracture (2/18). While focal radiodensity related to the SCP procedure was retrospectively identifiable on postoperative radiography in all except 1 case (10/11), postprocedural findings were not described by the interpreting radiologist in 6/11 cases. On CT, the average injected synthetic calcium phosphate (CaP) volume was 1.15 cm³ (SD = 0.33 cm³); mean CT attenuation of the injectate was 1220 HU (range 1058-1465 HU). In all patients who had pre- and postoperative MRI (5/18), BML size decreased on follow-up MRI. Extra-osseous extrusion of CaP was not seen on postoperative radiography, CT, or MRI. Conclusion: Physicians should be aware of the expanding preoperative indications and postoperative imaging findings of SCP, which is being performed with increasing frequency in the ankle and hindfoot.Levels of Evidence: Diagnostic, Level III: Retrospective cohort study.

Bone Grafting Options

Union rates vary for arthrodesis sites and bone healing in foot and ankle surgery. The ultimate goal is to achieve complete bone healing within a reasonable time. There are many factors that surgeons cannot control, such as the patient's compliance and ability to heal. However, surgeons can control osseous preparation, stable fixation, preservation of soft tissue, and the osseous fusion initial healing environment. Modification of the healing environment can be achieved with the use of bone graft and orthobiologics. This article discusses the grafts and orthobiologics that can be used in bone healing for the foot and ankle.

Platelet-Rich Fibrin and its Emerging Therapeutic Benefits for Musculoskeletal Injury Treatment

New therapies that accelerate musculoskeletal tissue recovery are highly desirable. Platelet-rich fibrin (PRF) is a leukocyte- and platelet-rich fibrin biomaterial that acts as a binding site for both platelets and growth factors. Through increasing the local concentration of growth factors at specific tissues, PRF promotes tissue regeneration. PRF has been frequently used in combination with bone graft materials to reduce healing times and promote bone regeneration during maxillofacial surgery. However, its benefits during muscle repair and recovery are less well-documented. Here, we perform a narrative review on PRF therapies and muscle injuries to ascertain its beneficial effects. We reviewed the factors that contribute to the biological activity of PRF and the published pre-clinical and clinical evidence to support its emerging use in musculoskeletal therapy. We include in vitro studies, in vivo animal studies and clinical articles highlighting both the success and failures of PRF treatment. PRF can promote the healing process when used in a range of orthopaedic and sports-related injuries. These include cartilage repair, rotator cuff surgery and anterior cruciate ligament surgery. However, conflicting data for these benefits have been reported, most likely due to inconsistencies in both PRF preparation protocols and dosing regimens. Despite this, the literature generally supports the use of PRF as a beneficial adjuvant for a range of chronic muscle, tendon, bone or other soft tissue injuries. Further clinical trials to confirm these benefits require consistency in PRF preparation and the classification of a successful clinical outcome to fully harness its potential.

Bacterial contamination rate and associated factors during bone and tendon allograft procurement from Spanish donors: exploring the contamination patterns

BACKGROUND

Allograft contamination during extraction represents a major limiting factor for tissue bank availability. Contamination rates remain persistently high independent of the hospital, country or year considered.

AIM

To analyse the factors associated with contamination of bone and tendon samples extracted from Spanish donors.

METHODS

Data for 1162 bone and tendon samples extracted from 102 donors between 2014 and 2017 were collected retrospectively from the hospital database. Descriptive statistics, potentially associated factors and correlation of contamination between samples extracted from different anatomical locations of the same donor were analysed.

FINDINGS

In total, 227 (19.54%) of the extracted samples [131 (18.49%) bone samples and 96 (20.92%) tendon samples] rendered positive cultures and were discarded. Male sex [odds ratio (OR) 2.023; P=0.019], extraction of >10 samples per donor (OR 1.997; P<0.001) and extraction time >240 min (OR 1.755; P=0.001) were factors independently associated with a higher contamination rate. Meanwhile, the tissue sample type 'bone-patellar tendon-bone' was associated with a significantly lower contamination rate (OR 0.446; P=0.001). Significant correlation between certain localization of contaminated samples and the concordance of bacterial species was also observed.

CONCLUSION

Factors related to the extraction procedure, such as total extraction time, extraction sequence, number of samples extracted and anatomical location of extracted samples, play a major role in allograft contamination. Further optimization of procedures, guided by the contamination patterns analysed in this study, should help to increase tissue bank availability.

The role of biologic in foot and ankle trauma-a review of the literature

PURPOSE OF REVIEW

The use of biologics in orthopedics is becoming increasingly popular as an adjuvant in healing musculoskeletal injuries. Though many biologics involved in the management of foot and ankle injuries are used based on physician preference, reports of improved outcomes when combined with standard operative treatment has led to further clinical interest especially in foot and ankle trauma.

RECENT FINDINGS

The most recent studies have shown benefits for biologic use in patients predisposed to poor bone and soft tissue healing. Biologics have shown benefit in treating soft tissue injuries such as Achilles ruptures as well as the complications of trauma such as non-unions and osteoarthritis. Biologics have shown some benefit in improving functional and pain scores, as well as reducing time to heal in foot and ankle traumatic injuries, with particular success shown with patients that have risk factors for poor healing. As the use of biologics continues to increase, there is a need for high-level studies to confirm early findings of lower level reports.

Use of autologous bone grafting from the calcaneus and interconnected porous hydroxyapatite ceramic for bone transplantation in rheumatoid foot surgery

Cancellous bone grafts from the calcaneus have been used for the foot and ankle as well as iliac bone graft; however, there is a sparse report for calcaneal bone transplantation in the field of rheumatoid foot surgery. In this study, safety and usefulness of calcaneal bone grafts, and combination with interconnected porous hydroxyapatite ceramic, was evaluated in rheumatoid arthritis foot surgeries. Of six rheumatoid arthritis cases, three (talo-navicular joint fusion) used a calcaneal bone graft alone, and the remaining three cases (subtalar joint and talo-navicular joint fusion) used a combination of calcaneal bone graft and interconnected porous hydroxyapatite ceramic augmented with dense calcium hydroxyapatite for subtalar bony defect (1.5–2.0 cm) after the correction. Pre- and postoperative Japanese Society for Surgery of the Foot rheumatoid arthritis foot ankle scale scores were obtained for the clinical assessment. As radiographic assessment, tibio-calcaneal angle, calcaneal pitch, talo-1st metatarsal angle, and pronated foot index were also evaluated. After starting weight-bearing or walking, there was no pain and skin trouble at the fusion and harvesting sites. All cases achieved bony fusion within 6–10 weeks. Japanese Society for Surgery of the Foot rheumatoid arthritis foot ankle score was improved in all six cases. Furthermore, tibio-calcaneal angle, talo-1st metatarsal angle, and pronated foot index were also improved at latest follow-up in all cases. In conclusion, autologous bone grafting from the calcaneus was safe and convenient even in rheumatoid foot surgeries. For larger bony defects (1.5–2.0 cm), combination use with interconnected porous hydroxyapatite ceramic augmented with dense calcium hydroxyapatite was also useful.

Living Cryopreserved Bone Allograft as an Adjunct for Hindfoot Arthrodesis

Hindfoot arthrodesis is a frequently performed procedure by foot and ankle surgeons. The relatively high nonunion rate associated with these procedures has led surgeons to use adjunctive bone graft to help augment osseous union. Cellular bone allografts are a specific type of graft that incorporates osteoconductive, osteoinductive, and osteogenic properties while also eliminating the common disadvantages of autografts and traditional allografts. This article discusses the role of cellular bone allografts in hindfoot arthrodesis procedures, a review of current literature, and a comparison of available products.