Research progress on the biological modifications of implant materials in 3D printed intervertebral fusion cages.

Anterior spine decompression and reconstruction with bone grafts and fusion is a routine spinal surgery. The intervertebral fusion cage can maintain intervertebral height and provide a bone graft window. Titanium fusion cages are the most widely used metal material in spinal clinical applications. However, there is a certain incidence of complications in clinical follow-ups, such as pseudoarticulation formation and implant displacement due to nonfusion of bone grafts in the cage. With the deepening research on metal materials, the properties of these materials have been developed from being biologically inert to having biological activity and biological functionalization, promoting adhesion, cell differentiation, and bone fusion. In addition, 3D printing, thin-film, active biological material, and 4D bioprinting technology are also being used in the biofunctionalization and intelligent advanced manufacturing processes of implant devices in the spine. This review focuses on the biofunctionalization of implant materials in 3D printed intervertebral fusion cages. The surface modifications of implant materials in metal endoscopy, material biocompatibility, and bioactive functionalizationare summarized. Furthermore, the prospects and challenges of the biofunctionalization of implant materials in spinal surgery are discussed. Fig.a.b.c.d.e.f.g As a pre-selected image for the cover, I really look forward to being selected. Special thanks to you for your comments.

Clinical Outcomes of Thoracolumbar Burst Fracture Treated by Trans-Kambin triangle versus Transpedicular Bone Grafting Combined with Posterior Internal Fixation.

OBJECTIVE: The ideal management of thoracolumbar burst fracture (TLBF) remains controversial. We conducted this study to compare the effectiveness and safety of trans-Kambin triangle versus transpedicular bone grafting combined with posterior internal fixation (PIF) for TLBF. METHODS: Fifty-four patients were retrospectively analyzed and divided into 2 groups: the observation group (PIF combined with bone grafting via the Kambin triangle, n = 28) and the control group (PIF combined with bone grafting via transpedicular, n = 26). The anterior vertebral height ratio, sagittal Cobb angle, visual analog scale score, Oswestry Disability Index, bone healing rate, and neurologic complications were measured. RESULTS: All patients were followed up regularly for a mean period of 17.94 months (12 - 24 months). The anterior vertebral height ratio in the observation group was higher than that in the control group (93.93 ± 2.92 vs. 89.90 ± 5.54%, P = 0.006), and the loss of correction was lower (1.59 ± 1.20 vs. 3.00 ± 1.98%, P = 0.008). The observation group had lower sagittal Cobb angle at final follow-up (8.68 ± 3.75 vs. 11.33 ± 4.77 degrees, P = 0.046) and less correction loss (1.96 ± 1.32 ± 1.15 vs. 3.90 ± 2.39 degrees, P = 0.002). The visual analog scale score and Oswestry Disability Index in the observation group were lower (0.61 ± 0.43 vs. 0.92 ± 0.38, P = 0.016; 15.86 ± 4.11 vs. 19.18 ± 4.04, P = 0.010), while the fracture healing rate showed no significant difference (P > 0.05). No internal fixation failure or neurologic complications occurred in both groups during the follow-up. CONCLUSIONS: Bone grafting via the Kambin triangle combined with PIF is a safe and effective technology for thoracolumbar burst fracture.

Bone Grafts and Substitutes in Dentistry: A Review of Current Trends and Developments.

After tooth loss, bone resorption is irreversible, leaving the area without adequate bone volume for successful implant treatment. Bone grafting is the only solution to reverse dental bone loss and is a well-accepted procedure required in one in every four dental implants. Research and development in materials, design and fabrication technologies have expanded over the years to achieve successful and long-lasting dental implants for tooth substitution. This review will critically present the various dental bone graft and substitute materials that have been used to achieve a successful dental implant. The article also reviews the properties of dental bone grafts and various dental bone substitutes that have been studied or are currently available commercially. The various classifications of bone grafts and substitutes, including natural and synthetic materials, are critically presented, and available commercial products in each category are discussed. Different bone substitute materials, including metals, ceramics, polymers, or their combinations, and their chemical, physical, and biocompatibility properties are explored. Limitations of the available materials are presented, and areas which require further research and development are highlighted. Tissue engineering hybrid constructions with enhanced bone regeneration ability, such as cell-based or growth factor-based bone substitutes, are discussed as an emerging area of development.

Understanding the Future Prospects of Synergizing Minimally Invasive Transforaminal Lumbar Interbody Fusion Surgery with Ceramics and Regenerative Cellular Therapies.

Transforaminal lumber interbody fusion (TLIF) is the last resort to address the lumber degenerative disorders such as spondylolisthesis, causing lower back pain. The current surgical intervention for these abnormalities includes open TLIF. However, in recent years, minimally invasive TLIF (MIS-TLIF) has gained a high momentum, as it could minimize the risk of infection, blood loss, and post-operative complications pertaining to fusion surgery. Further advancement in visualizing and guiding techniques along with grafting cage and materials are continuously improving the safety and efficacy of MIS-TLIF. These assistive techniques are also playing a crucial role to increase and improve the learning curve of surgeons. However, achieving an appropriate output through TLIF still remains a challenge, which might be synergized through 3D-printing and tissue engineering-based regenerative therapy. Owing to their differentiation potential, biomaterials such as stem/progenitor cells may contribute to restructuring lost or damaged tissues during MIS-TLIF, and this therapeutic efficacy could be further supplemented by platelet-derived biomaterials, leading to improved clinical outcomes. Thus, based on the above-mentioned strategies, we have comprehensively summarized recent developments in MIS-TLIF and its possible combinatorial regenerative therapies for rapid and long-term relief.

Inhibition of Autograft Bone Resorption by Antibone Resorptive Agents After Spinal Reconstruction Surgery for Extensive Cervical Chondrosarcoma: A Case Report with a 10-Year Follow-Up.

BACKGROUND: For the surgical treatment of spinal malignant tumor, spinal reconstruction with bone graft and instrumentation is necessary after tumor resection, but postoperative complications, including grafted bone resorption, may arise. CASE DESCRIPTION: A 42-year-old Asian woman presented with neck pain, tumorous masses on the neck, and left arm pain. Magnetic resonance imaging and computed tomography of the cervical spine showed extensive malignant spinal tumor. Histological examination of tumor biopsy revealed grade I chondrosarcoma. Complete resection of the tumor was performed using an anterior-posterior approach, followed by anterior iliac bone grafting and posterior spinal instrumentation. No tumor recurrence was observed on magnetic resonance imaging at final follow-up after 10 years. However, grafted bone resorption was identified immediately after surgery due to stress shielding by robust spinal instrumentation. To inhibit resorption of grafted bone, the bisphosphonate minodronate was administered for 5 years from 3 years postoperatively, before being replaced by denosumab from 8 years postoperatively. After use of these antibone resorptive agents, grafted bone resorption stopped. CONCLUSIONS: Anteriorly grafted bone resorption due to stress shielding may occur after reconstructive cervical spine surgery with robust posterior spinal instrumentation. Bisphosphonates and denosumab may be considered to inhibit grafted bone resorption.

Mid-term and long-term results of restoring rotation center in revision hip arthroplasty.

BACKGROUND: To restore rotation center exactly in revision hip arthroplasty is technically challenging, especially in Paprosky type III. The technical difficulty is attributable to the complicated acetabular bone defect. In this study, we discussed the method of restoring rotation center in revision hip arthroplasty and reported the clinical and radiological outcome of mid-term and long-term follow-up. METHODS: This study retrospectively reviewed 45 patients (48 hips) who underwent revision hip arthroplasty, in which 35 cases (35 hips) were available for complete follow-up data. During the operation, the acetabular bone defect was reconstructed by impaction morselized bone graft, and the hip rotation center was restored by using remnant Harris fossa and acetabular notches as the marks. The clinical outcome was assessed using the Harris hip score. Pelvis plain x-ray was used to assess implant migration, stability of implants, and incorporation of the bone graft to host bone. RESULT: The average follow-up duration was 97.60 months (range 72-168 months). The average Harris hip score improved from 29.54 ± 10.87 preoperatively to 83.77 ± 5.78 at the last follow-up. The vertical distance of hip rotation center measured on pelvis x-ray was restored to normal, with the mean distance (15.24 ± 1.31) mm (range 12.4~17.3 mm). The mean loss of vertical distance of hip rotation center was (2.21 ± 0.72) mm (range 1.1 ~ 5.3 mm) at the last follow-up. CONCLUSION: Satisfactory clinical and radiological outcome can be obtained through restoring hip rotation center by using remnant Harris fossa and acetabular notches as the anatomical marks in revision hip arthroplasty.

Radiological results of Shelf acetabuloplasty in adolescent hip dysplasia with aspherical femoral head: how to get an ideal placement of the Shelf graft.

Shelf acetabuloplasty continues to be effective in the prevention or delay of osteoarthritis in adolescent dysplastic hips. We aimed to evaluate the efficacy and to determine the correct level of the bone graft objectively. We retrospectively analyzed 16 hips underwent Shelf acetabuloplasty originated by Spitzy. The mean age at surgery was 15.3 years old with the mean caput index at 39.7%. The average follow-up was 11 years. The radiological evaluation was based on acetabular-head index (AHI) at preoperative and latest radiographs, acetabular-Shelf distance (ASD) and Shelf-head ratio at immediate postoperative and latest radiographs. The cutoff value for the ideal ASD was determined by receiver operating characteristic (ROC) and the Pearson correlation test used in statistical analysis to assess the relationship between ASD and Shelf graft resorption. Clinical evaluation was performed using Harris Hip Score (HHS) at the latest follow-up. The AHI was improved in all cases, from mean 56.9 to 91.0% (P < 0.001). The mean of ASD was 7 mm. In nine of the 16 cases, the Shelf graft was well united at the same level of the existing acetabulum with good continuity. The ROC curve showed the cutoff value for the ideal ASD was 6 mm. The Pearson correlation test also showed a positive relationship between ASD and Shelf graft resorption (P = 0.001). The average of HHS scores was 98.1 points. Both radiological and clinical results were acceptable. The ideal placement that keeps the shelf sufficient to bear the mechanical stress without bone resorption over time was at the level of 6 mm from the joint space. Level III - therapeutic study.

Sinus floor elevation using a new bovine bone grafting material: case report and bone grafting materials update / Actualización en materiales de relleno óseo: reporte de un caso clínico de elevamiento del piso del seno maxilar usando un nuevo material de relleno óseo bovino

Bone grafting is important to preserve the alveolar bone ridge height and volume for dental implant placement. Even though implant-supported overdentures present highly successful outcomes, it seems that a great number of edentulous individuals have not pursued implant-based rehabilitation. The cost of the treatment is one of the reasons of discrepancy between highly successful therapy and its acceptance. Therefore, the development of biomaterials for bone grafting with comparable characteristics and biological effects than those renowned internationally, is necessary. In addition, domestic manufacture would reduce the high costs in public health arising from the application of these biomaterials in the dental feld. The purpose of this clinical case report is to provide preliminary clinical evidence of the efficacy of a new bovine bone graft in the bone healing process when used for sinus floor elevation. (AU)

El uso de injertos óseos es importante para preservar la altura y el volumen de la cresta alveolar para la colocación de implantes dentales. Si bien las sobredentaduras implanto-soportadas presentan resultados altamente exitosos, la mayoría de las personas desdentadas no han sido rehabilitadas mediante implantes dentales. Uno de los principales motivos por los cuales los pacientes no aceptan este tipo de tratamiento, altamente exitoso, es el elevado costo del mismo. Por ello, es necesario el desarrollo de biomateriales de injerto óseo con características y efectos biológicos comparables a los reconocidos internacionalmente. Asimismo, la fabricación nacional reduciría los altos costos en Salud Pública derivados de la aplicación de estos biomateriales en el campo dental. El objetivo de esta comunicación es presentar un caso clínico a fin de proporcionar evidencia preliminar acerca de la eficacia de un nuevo injerto de hueso bovino en el proceso de cicatrización ósea en el levantamiento del piso del seno maxilar. (AU)

Fibular strut allograft influences reduction and outcomes after locking plate fixation of comminuted proximal humeral fractures in elderly patients: a retrospective study.

BACKGROUND: Proximal humeral fractures (PHFs) are the third most commonly occurring fractures in elderly patients. Most of these fractures can be treated with conservative methods, but the optimal surgical treatment strategy for unstable fractures in elderly patients remains controversial. This study aimed to compare the radiological and clinical outcomes between locking compression plate (LCP) fixation and LCP fixation with fibular allograft implantation for the treatment of comminuted PHFs. METHODS: We retrospectively reviewed 60 patients (mean age, 72.75 years) with closed 3- or 4-part fractures, and a minimum of 2 years of follow-up. Fracture reduction was quantitatively determined by humeral head height (HHH) and neck-shaft angle (NSA). The clinical outcome was evaluated by Constant-Murley score (CMS) and American Shoulder and Elbow Surgeons (ASES) score. RESULT: The average radiological changes were higher in the LCP group than in the locking plate with fibular allograft group (HHH of 4.16 mm vs 1.18 mm [p < 0.001] and NSA of 9.94° versus 3.12° [p < 0.001]) . The final average outcome scores were lower in the LCP group than in the FA group (CMS of 73.00 vs 78.96 [p = 0.024] and ASES score of 72.80 vs 78.64 [p = 0.022]). The FA group showed better forward elevation (p = 0.010) and abduction (p = 0.002); however, no significant differences were observed for shoulder external rotation or internal rotation. The number of complications was higher in the LCP group (28.57%) than in the FA group (1.2%) (p < 0.001). CONCLUSION: For comminuted PHFs in elderly patients, LCP fixation combined with a fibular allograft is reasonable option to ensure satisfactory radiological and clinical outcomes. TRIAL REGISTRATION: ZDYJLY(2018)New-9 . Name of registry: IEC for clinical Research of Zhongda Hospital, Affiliated to Southeast University. Date of registration: 2018-05-17.

Bone union of the transferred coracoid graft is the key factor affecting the extent of postoperative graft changes and the clinical results following the modified Bankart and Bristow procedure: a computed tomography scan study.

BACKGROUND: The extent of postoperative changes in the coracoid process grafted during the modified Bankart and Bristow procedure remains unclear. The purpose of the present study was to quantify the postoperative changes in bone surface area as assessed on computed tomography, as well as to clarify the impact of such changes on the clinical results. METHODS: Twenty-three shoulders of 21 subjects who underwent the modified Bankart and Bristow procedure were retrospectively analyzed. Computed tomography images were obtained immediately after surgery and at the final follow-up. The changes in bone surface area of the grafted coracoid process were measured on computed tomography slices in the proximity of the screw bore. Clinical outcomes were evaluated in terms of the Rowe, Walch-Duplay, and simple shoulder test scores. RESULTS: Bone area increased in 15 shoulders (65.2%) and decreased in eight shoulders (34.8%). Bone area increased by 51.3% in shoulders with bone union in the superior part of the coracoid process graft, with no significant differences between the superior and inferior sides of the graft regarding the rate of change in bone surface area (41.4% vs. 68.9% increase). However, in shoulders with bone union in the inferior part of the coracoid process graft, the rate of change in bone area differed significantly between the superior and inferior sides of the graft, exhibiting a 42.3% decrease on the superior side and 39.8% increase on the inferior side. In shoulders with no bone union, bone area decreased by 29.5% (17.4% vs. 39.3% decrease on the superior and inferior side, respectively), whereas the Rowe and Walch-Duplay scores were significantly lower than those noted in shoulders with bone union. CONCLUSIONS: Postoperative bone formation and bone resorption in the coracoid process grafted during the modified Bankart and Bristow procedure depend on whether and where bone union occurs. Graft non-union is associated with inferior clinical results.

Mechanistic role of perfusion culture on bone regeneration.

Bone tissue engineering (BTE) aims to develop engineered bone tissue to substitute conventional bone grafts. To achieve this, culturing the cells on the biocompatible three-dimensional (3D) scaffold is one alternative approach. The new functional bone tissue regeneration could be feasible by the synergetic combinations of cells, biomaterials and bioreactors. Although the field of biomaterial design/development for BTE applications attained reasonable success, development of suitable bioreactor remains still a major challenge. Tissue engineering bioreactors provide the microenvironment required for neo-tissue regeneration, and also can be used to study the physio-chemical cues effect on cell proliferation and differentiation in order to produce functional tissue. In this direction, various bioreactors have been developed and evaluated for the successful development of engineered bone tissue. Continues assessment of tissue development and limitations of the bioreactors lead to the progression of perfusion flow bioreactor system. Improvements in perfusion reactor system were able to yield multiple tissue engineered constructs with uniform cell distribution, easy to operate protocols and also effectively handled for the functional tissue development to meet the adequate supply of engineered graft for clinical application.

Bovine bone particulates containing bone anabolic factors as a potential xenogenic bone graft substitute.

BACKGROUND: Alternative grafts are needed to improve the healing of bone non-union. Here, we assessed a bovine bone product which retains the inorganic and organic components of bone, as an alternative bone graft. METHODS: Bovine bone matrix proteins (BBMPs) were isolated from bovine bone particulates (BBPs) and tested in vitro. Primary rat osteoblast viability, differentiation, and mineralisation were assessed with alamarBlue®, real-time PCR, and von Kossa staining assays, respectively. Osteoclast formation was assessed in primary murine bone marrow cultures with TRAP staining. Human osteoblast growth and differentiation in the presence of BBPs was evaluated in 3D collagen gels in vitro using alamarBlue® and real-time PCR, respectively. The efficacy of BBPs as an alternative bone graft was tested in a rat critical-size calvarial defect model, with histology scored at 4 and 12 weeks post-surgery. RESULTS: In vitro, the highest concentration of BBMPs increased mineral deposition five-fold compared to the untreated control group (P < 0.05); enhanced the expression of key osteoblast genes encoding for RUNX2, alkaline phosphatase, and osteocalcin (P < 0.05); and decreased osteoclast formation three-fold, compared to the untreated control group (P < 0.05). However, the BBPs had no effect on primary human osteoblasts in vitro, and in vivo, no difference was found in healing between the BBP-treated group and the untreated control group. CONCLUSIONS: Overall, despite the positive effects of the BBMPs on the cells of the bone, the bovine bone product as a whole did not enhance bone healing. Finding a way to harness the positive effect of these BBMPs would provide a clear benefit for healing bone non-union.

Outcome of Primary Bone Fragment Replacement in Pediatric Patients with Depressed Skull Fracture.

OBJECTIVE: To evaluate pediatric patients who were operated with the diagnosis of depressed skull fracture. METHODS: The records of pediatric patients who presented with traumatic head injury to multicenter neurosurgery clinics between 2002 and 2018 and who were operated with a diagnosis of depressed skull fracture were retrospectively reviewed. All of the patients underwent primary bone fragment replacement operation, and the patients' own bone flaps were used to repair depressed skull fractures in all of them. RESULTS: A total of 78 patients were included in the study. Of the study group, 20 patients presented with mild head injury, 37 had moderate head injury, and 21 had severe head injury. Dural injury was present in 67 patients (86%) and the dura was intact in 11 patients (14%). After surgery, 63 patients (81%) had good outcome, 8 patients (10%) had moderate disability, and 5 patients (6.5%) had severe disability. Two patients with multiple accompanying cranial pathologies died and the mortality rate was 2.5%. Infection was detected in only 2 of the 78 patients who were treated within the first 72 h after trauma. One of them had meningitis and the other skin infection. Both patients were treated with appropriate antibiotherapy. None of the patients in the study group had an infection involving the bone, such as osteomyelitis, or the tissues under the bone, such as subdural-epidu-ral empyema or abscess. None of the patients required reoperation and removal of the bone. CONCLUSION: In the present study, as the pathologies accompanying the depressed skull fractures of the patients increased, Glasgow Coma Scale scores at arrival and Glasgow Outcome Scale scores at discharge decreased. Regardless of whether the depressed fracture is simple or compound, primary bone fragment replacement with appropriate decontamination of the fractured bone and operation area via single-session intervention gives good results. It is important to perform the surgery as soon as possible to reduce the risk of contamination. Primary bone fragment replacement seems to be an appropriate treatment option for depressed skull fractures.

Outcomes after bone grafting in patients with and without ACL revision surgery: a retrospective study.

BACKGROUND: Current literature is lacking of data regarding functional outcomes in patients following bone tunnel grafting with or without revision anterior cruciate ligament (ACL) reconstruction. Therefore, the aim of the present study was to evaluate the clinical outcome in patients with (RACL) or without revision ACL reconstruction (OBG) following bone grafting. METHODS: Fifty-nine patients (18 female, 41 male) who underwent bone grafting due to recurrent, symptomatic ACL deficiency following ACL reconstruction between 2011 and 2014 were retrospectively analyzed. In 44 patients (mean age: 30,5 ± 8,5 years) a staged revision ACL reconstruction (RACL) was performed after bone grafting. 10 patients (mean age: 33.2 ± 10.3 years) refused to have ACL revision surgery after bone grafting (OBG). Outcome measures included instrumented laxity testing, the International Knee Documentation Committee (IKDC) score, the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm score and Tegner activity scale. RESULTS: After mean period of 33,9 ± 17.0 months, 54 patients were available for follow up examination. In the RACL group, the Lysholm score was 77,2 ± 15,5 (range 35-100), the mean IKDC subjective knee score was 69,0 ± 13,4 (range 39,1-97,7) and the mean Tegner activity score was 4,1 ± 1,5 (range, 1-9). Similarly, in the OBG group the mean Lysholm score was 72,90 ± 18,7 (range 50-100), the mean IKDC subjective score was 69,3 ± 20,0 (range 44,1-100) and the mean Tegner activity score was 4,6 ± 1,2 (range, 3-6). No significant difference was observed between the two groups. Knee laxity measurements were elevated without revision ACL surgery, however the difference was not significant. CONCLUSION: Bone tunnel grafting with or without second stage ACL revision surgery showed no significant difference in functional outcome score. Thus, in case of revision ACL instability careful patient selection is necessary and expectations should be discussed openly with the patients.

A case of bilateral revision total knee arthroplasty using distal femoral allograft-prosthesis composite and femoral head allografting at the tibial site with a varus-valgus constrained prosthesis: ten-year follow up.

BACKGROUND: We report the successful use of allograft-prosthesis composite (APC) and structural femoral head allografting in the bilateral reconstruction of large femoral and tibial uncontained defects during revision total knee arthroplasty (RTKA). CASE PRESENTATION: A 67-year-old female with degenerative arthritis underwent bilateral total knee arthroplasty (TKA) using the Press Fit Condylar (PFC) modular knee system at our clinic in March, 1996. At 8 years postoperatively, the patient presented with painful, bilateral varus knees, with swelling, limited passive range of motion (ROM), and severe instability. We treated to reconstruct both knee using a femoral head allograft at the tibial site, a structural distal femoral allograft at the femoral site, and a varus-valgus constrained (VVC) prosthesis with cement. At the 10-year follow up, we found no infection, graft failure, loosening of implants, in spite of using massive bilateral structural femoral head allografts in RTKA. CONCLUSION: The use of APC enabled a stable and durable reconstruction in this uncommon presentation with large femoral bone deficiencies encountered during a RTKA.

Iliac Crest Bone Graft for Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Prospective Analysis of Inpatient Pain, Narcotics Consumption, and Costs.

STUDY DESIGN: Retrospective Analysis OBJECTIVE.: The aim of this study was to determine whether an association between increased acute pain, postoperative time, and direct hospital costs exists between the use of iliac crest bone grafting (ICBG) and bone morphogenic protein (BMP)-2 following a primary, single-level minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). SUMMARY OF BACKGROUND DATA: ICBG has been associated with enhanced fusion rates. Concerns have been raised in regards to increased operative time and postoperative pain. The advantages of ICBG compared to other spinal fusion adjuncts have been debated. METHODS: Prospective, consecutive analysis of patients undergoing primary, single-level MIS TLIF with ICBG was compared to a historical cohort of consecutive patients that received BMP-2. Operative characteristics were compared between groups using χ analysis or independent t test for categorical and continuous variables, respectively. Postoperative inpatient pain was measured using the Visual Analog Scale, and inpatient narcotics consumption was quantified as oral morphine equivalents. Outcomes were compared between groups using multivariate regression controlling for preoperative characteristics. RESULTS: A total of 98 patients were included in this analysis, 49 in each cohort. No significant differences were noted between cohorts with exception to sex (Females: ICBG, 53.06% vs. BMP-2, 32.65%, P = 0.041). There was a significant increase in operative time (14.53 minutes, P = 0.006) and estimated blood loss (16.64 mL, P = 0.014) in the ICBG cohort. Narcotics consumption was similar between groups on postoperative days 0 and 1. ICBG was associated with decreased total direct costs ($19,315 vs. $21,645, P < 0.001) as compared to BMP-2. CONCLUSION: Patients undergoing MIS TLIF with ICBG experienced increases in operative time and estimated blood loss that were not clinically significant. Furthermore, iliac crest harvesting did not result in an increase in acute pain or narcotics consumption. Further follow-up is necessary to determine the associated arthrodesis rates and long-term outcomes between each cohort. LEVEL OF EVIDENCE: 3.

Subcutaneous emphysema of the leg after hardware removal and bone allografting for infected non-union of the distal femur.

BACKGROUND: Infected non-unions of the supracondylar region of the femur are uncommon. Even though hardware removal is a common procedure, it may lead to complications, including neurovascular injury, refracture, worsening pain or recurrence of deformity. CASE PRESENTATION: We report on a male who developed subcutaneous emphysema of the leg after hardware removal and bone allografting for an infected non-union of the distal femur. He was managed by debridement of the surgical wound, antibiotic therapy, multiple fasciotomies, and application of a VAC (vacuum-assisted closure) system. CONCLUSIONS: Although subcutaneous emphysema of the leg after hardware removal and bone allografting for infected non-union of the distal femur is extremely rare, the potential life treating complications and their potential impact on the functional status of the patient have to be taken into consideration when counseling patients about this procedure. Even when it is not possible to identify a bacterial pathogen responsible for the subcutaneous emphysema of the leg, prompt intervention may save the limb of the patient.

[Synthetic bone replacement : Current developments and perspectives]. / Synthetischer Knochenersatz : Aktuelle Entwicklungen und Perspektiven.

Successful reconstruction of critical bone defects requires complete elimination of the underlying pathology, preservation or restoration of mechanical stability of the affected bone segment and, most importantly, an adequate filling material that supports the regeneration and formation of new bone within the treated defect in an optimal fashion. Currently available synthetic bone graft substitutes cannot address all requirements of such a complex biological process individually. Due their suboptimal and, with respect to physiological bone healing, asynchronous biodegradation properties, their specific foreign material-mediated side effects and complications and fairly modest overall osteogenic potential, their overall clinical performance typically lags behind conventional bone grafts. However, a defect and pathology specific combination of synthetic bone graft substitutes with appropriate carrier properties, therapeutic agents and/or conventional bone graft materials allows the creation of biologically enhanced composite constructs that can surpass the biological and therapeutic limits of autologous bone grafts. This monograph presents a new concept based on the biological enhancement of optimal therapeutic agent-carrier composites and provides a rationale for an individual, requirement-specific adaptation of a truly patient-specific bone defect reconstruction.

Bone Substitute Materials and Minimally Invasive Surgery: A Convergence of Fracture Treatment for Compromised Bone.

This article focuses on the understanding of the biochemistry and surgical application of bone substitute materials (BSMs) and particularly the newer calcium phosphate materials that can form a structural orthobiologic matrix within the metaphyseal components of the periarticular bone. Six characteristics of BSMs are detailed that can be used as a guide for the proper selection and application of the optimal BSM type for periarticular fracture repair. These 6 characteristics of BSMs are divided into 2 pillars. One pillar details the 3 biochemical features of BSMs and the other pillar details the 3 surgical application properties.

Surgical Technique Trends in Primary ACL Reconstruction from 2007 to 2014.

BACKGROUND: The surgical technique for anterior cruciate ligament (ACL) reconstruction has evolved as a result of improved understanding of ligament biomechanics, anatomy, device development, and failed reconstructions. Studies on surgical technique preferences have been limited to surgeon surveys, which are subject to selection and recall bias. The purpose of this study was to evaluate ACL reconstruction surgical technique and yearly revision rate trends in a community-based setting. METHODS: A population-based epidemiological study was conducted using data on primary ACL reconstruction procedures registered in an ACL reconstruction registry from 2007 to 2014. Changes in the incidence rates of different types of femoral tunnel drilling methods, different types of grafts and graft fixation, and revisions were studied. Adjusted incidence rate ratios (IRRs) are provided. RESULTS: Of the 21,686 ACL reconstructions studied, 72.4% were performed by sports medicine fellowship-trained surgeons. The incidence rate of femoral tunnel drilling via a tibial tunnel decreased at an adjusted rate of 26% per year (IRR = 0.74, 95% confidence interval [CI] = 0.71 to 0.78), from 56.4% to 17.6% during the study period. The incidence rate of medial portal drilling increased from 41.3% to 65.1% at an adjusted rate of 11% per year (IRR = 1.11, 95% CI = 1.09 to 1.13), and the incidence rate of drilling through a lateral approach increased from 2.3% to 17.3% at an adjusted rate of 53% per year (IRR = 1.53, 95% CI = 1.39 to 1.67). There was no change in the use of hamstring autograft, bone-patellar tendon-bone autograft, or tibial tendon allograft. Use of first-generation bioabsorbable femoral and tibial fixation decreased for all graft types. For soft-tissue grafts, usage of suspensory metal femoral fixation increased 12% to 13% per year (IRR = 1.12, 95% CI = 1.09 to 1.15 for tibial tendon grafts; IRR = 1.13, 95% CI = 1.10 to 1.15 for hamstring grafts). For bone-patellar tendon-bone autografts, the use of femoral fixation with interference biocomposite screws increased 7% per year (IRR = 1.07, 95% CI = 1.04 to 1.10). On the tibial side, utilization of biocomposite screws increased for all graft types. No association was found between revision rate and the year of the primary operation. CONCLUSIONS: Surgeons changed their femoral tunnel drilling technique over the study period, whereas the incidence rates of specific graft utilization remained stable. There has been a shift away from first-generation bioabsorbable fixation and increasing use of biocomposite fixation across all graft types. Early cumulative revision rates remained stable.