Management of aseptic tibial nonunion

Immunomodulation Pathogenesis and Treatment of Bone Nonunion

Fractures and bone nonunion commonly require surgical intervention. Serious outcomes of non-healing in the late stages of fracture place a significant financial burden on society and families. Bone nonunion occurs when a fracture stops healing, for many reasons, and leads to a variety of bad outcomes. Numerous factors, including biomechanics and immunology, are involved in the complicated mechanisms of bone nonunion. The immune-inflammatory response plays a significant part in the emergence of bone nonunion, and the occurrence, control, and remission of inflammation in the bone healing process have a significant influence on the ultimate success of bone tissue repair. In the bone microenvironment, immune cells and associated cytokines control bone repair, which is significantly influenced by macrophages, T cells, and fibroblast growth factor. To limit acute inflammation and  balance osteogenesis and osteoblastogenesis for tissue repair and regeneration, immune cells and various cytokines in the local microenvironment must be precisely regulated. As a bad complication of late-stage fractures, bone nonunion has a significant effect on patients' quality of life and socioeconomic development. Therefore, in-depth research on its pathogenesis and treatment methods has important clinical value. To provide more precise, focused therapeutic options for the treatment of bone nonunion, we discuss the regulatory roles of the key immune cells engaged in bone healing within the microenvironment during bone healing and their effect on osteogenesis.

Osteogenesis Stimulator Devices Reduce Surgical Intervention, Opioid Utilization, and Overall Costs in Patients with Fracture Nonunions

Background

Approximately 10% of fractures result in delayed union or nonunion. These cases result in pain and disability as well as increased utilization of healthcare resources such as pain medication, physical therapy, and subsequent surgery. Osteogenesis stimulator devices are a safe and low-cost, non-invasive option to aid healing in nonunion cases.

Objective

Study objectives aimed to evaluate real-world data of osteogenesis stimulator device usage in a variety of healthcare utilization endpoints including surgical intervention for nonunion, pain medication use, and overall healthcare costs. Data were stratified into three groups: the Stim Device group and the No Stim and Surgical control groups.

Methods

A retrospective analysis of a large claims-based database was conducted. The database was queried for adult patients having a diagnosis of nonunion, with evidence of a prior fracture in the previous 180 days (n = 11,010). The osteogenesis stimulator group (Stim Device group, n = 1,628) was defined as those patients having at least one claim for an osteogenesis stimulator in the period 90 to 180 days following fracture and up to 60 days following the nonunion diagnosis. The control group (No Stim group, n = 9,382) had a nonunion diagnosis with evidence of a fracture in the prior 180 days but did not receive a device. A total of 1,751 patients from the No Stim group were sub-grouped into surgical/operative controls (No Stim - Surgical group).

Results

Stim Device patients showed lower rates of surgical intervention for their bone nonunion compared to the No Stim patients (214/1,628, 13.1% vs. 1,751/9,382, 18.7%, p < 0.001). Stim Device patients had lower rates of opioid utilization post-index compared to No Stim patients (948/1,628, 58.2% vs. 6,359/9,382, 67.8%, p < 0.001). Overall healthcare costs were significantly reduced in the Stim Device group ($21,654) compared with No Stim ($29,101; p < 0.001) and Surgical ($35,914; p < 0.001) control groups.

Conclusion

The results show that bone growth stimulator devices have a positive individual and societal impact on treating patients with fracture nonunions.

Electrical Stimulation of Human Adipose-Derived Mesenchymal Stem Cells on O2 Plasma-Treated ITO Glass Promotes Osteogenic Differentiation

Electrical signals represent an essential form of cellular communication. For decades, electrical stimulation has been used effectively in clinical practice to enhance bone healing. However, the detailed mechanisms between electrical stimulation and bone healing are not well understood. In addition, there have been many difficulties in setting up a stable and efficient electrical stimulation system within the in vitro environment. Therefore, various conductive materials and electrical stimulation methods have been tested to establish an effective electrical stimulation system. Through these systems, many studies have been conducted on the effects of electrical stimulation on bone healing and osteogenic differentiation. However, previous studies were limited by the use of opaque conductive materials that obscure the cells; fluorescent observations and staining are known to be two of the critical methods to confirm the states of the cells. Indium tin oxide (ITO) glass is known to have excellent transparency and conductivity, but it is challenging to cultivate cells due to low cell adhesion characteristics. Therefore, we used O2 plasma treatment to increase the hydrophilicity and wettability of ITO glass. This enhanced cell affinity to the glass, providing a stable surface for the cells to attach. Then, electrical stimulation was applied with an amplitude range of 10 to 200 µA at a frequency of 10 Hz. Our results demonstrated that the osteogenic differentiation efficiency was maximized under the amplitude conditions of 10 µA and 50 µA. Accordingly, the results of our study suggest the development of an excellent platform in the field of biological research as a good tool to elucidate various mechanisms of cell bioactivity under electrical conditions.

A Review of Proximal Tibia Entry Points for Intramedullary Nailing and Validation of The Lateral Parapatellar Approach as Extra-articular

Tibial shaft fractures are the most common long bone injury and are often treated surgically in an attempt to minimize complications. Although treatment options for tibial shaft fractures vary based on factors including open injury, severity of fracture, and soft tissue status, intramedullary nailing in adults has emerged as the preferred definitive option for stabilization. Therefore, the primary purposes of this review and cadaveric study were to evaluate the entry points for reamed tibial nails and the risks, benefits, and advantages of each approach. Due to concerns of violating the joint capsule and the generalized applicability to everyday practice of the extra-articular lateral parapatellar semi-extended technique, the secondary goal of this manuscript was to evaluate whether an intramedullary tibial nail can be consistently placed extra-articularly using the lateral parapatellar technique described by Kubiak et al. and generalizability to surgeons of varying experience.

Risk Factors and Consequences of Lower Extremity Fracture Nonunions in Veterans With Spinal Cord Injury

We used Veterans Health Administration (VHA) national administrative data files to identify a cohort (fiscal years 2005–2014) of veterans with spinal cord injuries and disorders (SCID) to determine risk factors for and consequences of lower extremity fracture nonunions. Odds ratios (OR) for fracture nonunion were computed using multivariable‐adjusted logistic regression models. We identified three risk factors for nonunion: (i) older age (OR = 2.29; 95% confidence interval [CI] 1.21–4.33), (ii) longer duration of SCID (OR = 1.02; 95% CI 1.00–1.04), and (iii) fracture site (distal femur), with OR (comparison distal femur) including distal tibia/fibula (OR = 0.14; 95% CI 0.09–0.24), proximal tibia/fibula (OR = 0.19; 95% CI 0.09–0.38), proximal femur (OR = 0.10; 95% CI 0.04–0.21), and hip (OR = 0.13; 95% CI 0.07–0.26). Nonunions resulted in multiple complications, with upwards of 1/3 developing a pressure injury, 13% osteomyelitis, and almost 25% requiring a subsequent amputation. Our data have identified a high‐risk population for fracture nonunion of older veterans with a long duration of SCID who sustain a distal femur fracture. In view of the serious complications of these nonunions, targeted interventions in these high‐risk individuals who have any signs of delayed union should be considered. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Acute correction and intramedullary nailing of aseptic oligotrophic and atrophic tibial nonunions with deformity

Objectives

This study aims to describe the important points for treatment of aseptic tibial oligotrophic and atrophic nonunions by intramedullary nailing (IMN).

Patients and methods

The retrospective study included 17 biologically nonactive nonunion patients (12 males, 5 females; mean age 36.4 years; range, 19 to 49 years) operated between February 2010 and November 2017 by deformity correction, static IMN and autografting. The mean follow-up time was 4.2 (range, 3 to 7) years. The initial fracture management was external fixator for all patients. Fourteen patients had open fractures initially. Six patients had valgus, four patients had varus, three patients had oblique plane, and four patients had external rotational deformity. Nonunion diagnosis was established on the basis of the patient history and physical examination based on plain radiographs, computed tomography or both. All patients were evaluated by the same protocol to exclude any infection.

Results

The median time from injury to nailing was mean 10.3 (range, 6.1 to 36.5) months. Radiologic and clinical union was achieved in all patients. The mean union time was 3.64 (range, 3 to 6) months. Three patients had positive intraoperative bacteriological culture. In four patients, dynamization was necessary for consolidation. Late deep infection developed in three patients after union, and all infected cases were operated by implant removal, debridement, and appropriate antibiotics.

Conclusion

Intramedullary nailing and autografting after external fixator provide good results for the treatment of aseptic biologically nonactive nonunions with deformity. Reamed IMN ensures sufficient deformity correction, biological environment, and mechanical stability. The infection risk should always be kept in mind and patients should be followed-up closely to prevent complications.

Variability of orthopedic physician fracture location identification: Implications for bone stimulator treatment

INTRODUCTION

Aseptic non-union is a significant complication in approximately 5% of long-bone fractures. External bone stimulation treatment is often attempted before more invasive surgical interventions. Bone stimulators can have favorable results, but have a limited 1.7cm therapeutic radius. This study evaluated the accuracy by which clinicians locate a fracture on a cadaveric model. This has implications for the clinician's ability to accurately counsel patients on daily bone stimulator placement. Additionally, physicians (orthopedic attending surgeons and residents) were compared with pre-clinical (M1 and M2) medical students to evaluate if higher levels of training improved accuracy.

HYPOTHESIS

Orthopedic physicians and pre-clinical medical students will localize a radiographic fracture within 1.7cm less than 100% of the time, which represents the ideal consistency for patient care. Furthermore, orthopedic physicians will achieve a higher percentage accuracy than pre-clinical medical students.

MATERIALS AND METHODS

The sample included 20 orthopedic physicians and 16 pre-clinical medical students. Upper (radius) and lower (tibia) extremity cadaver models were prepared by inducing a single, transverse diaphyseal fracture. Plain reference radiographs of each model were obtained. Participants placed a radiopaque marker onto each model at the perceived fracture location, and radiographs were taken to document placement. Perpendicular marker-to-fracture distance was measured to the nearest mm along each bone's long axis using the PACS system.

RESULTS

Placement within the therapeutic radius was achieved by 70-80% of physicians, and 69-75% of medical students. In the remaining participants, improper placement distances were lower among physicians than among medical students (radius: 2.1±0.5 vs. 3.6±0.9cm, p=0.02; tibia: 2.6±0.5 vs 3.5±0.5cm, p=0.89).

DISCUSSION

In two cadaveric fracture models, up to 30% of orthopedic surgeons perceived a fracture location to be outside a bone stimulator's 1.7cm therapeutic radius. This finding suggests that physicians and their patients may benefit from additional methods for specifying the location of a non-union before commencing daily bone stimulator treatment.

LEVEL OF EVIDENCE

Level IV, prospective cohort study-evidence from a well-designed prospective cohort study.

Impact of Alcohol on Bone Health, Homeostasis and Fracture repair

Purpose of review

Alcohol use continues to rise globally. We review the current literature on the effect of alcohol on bone health, homeostasis and fracture repair to highlight what has been learned in people and animal models of alcohol consumption.

Recent findings

Recently, forkhead box O (FoxO) has been found to be upregulated and activated in mesenchymal stem cells (MSC) exposed to alcohol. FoxO has also been found to modulate Wnt/β-catenin signaling, which is necessary for MSC differentiation. Recent evidence suggests alcohol activates FoxO signaling, which may be dysregulating Wnt/β-catenin signaling in MSCs cultured in alcohol.

Summary

This review highlights the negative health effects learned from people and chronic and episodic binge alcohol consumption animal models. Studies using chronic alcohol exposure or alcohol exposure then bone fracture repair model have explored several different cellular and molecular signaling pathways important for bone homeostasis and fracture repair, and offer potential for future experiments to explore additional signaling pathways that may be dysregulated by alcohol exposure.

An experimental evaluation of fracture movement in two alternative tibial fracture fixation models using a vibrating platform

Several studies have investigated the effect of low-magnitude-high-frequency vibration on the outcome of fracture healing in animal models. The aim of this study was to quantify and compare the micromovement at the fracture gap in a tibial fracture fixed with an external fixator in both a surrogate model of a tibial fracture and a cadaver human leg under static loading, both subjected to vibration. The constructs were loaded under static axial loads of 50, 100, 150 and 200 N and then subjected to vibration at each load using a commercial vibration platform, using a DVRT sensor to quantify static and dynamic fracture movement. The overall stiffness of the cadaver leg was significantly higher than the surrogate model under static loading. This resulted in a significantly higher fracture movement in the surrogate model. Under vibration, the fracture movements induced at the fracture gap in the surrogate model and the cadaver leg were 0.024 ± 0.009 mm and 0.016 ± 0.002 mm, respectively, at 200 N loading. Soft tissues can alter the overall stiffness and fracture movement recorded in biomechanical studies investigating the effect of various devices or therapies. While the relative comparison between the devices or therapies may remain valid, absolute magnitude of recordings measured externally must be interpreted with caution.

The diaphyseal aseptic tibial nonunions after failed previous treatment options managed with the reamed intramedullary locking nail

BACKGROUND

The nonunion of open and closed tibial shaft fractures continues to be a common complication of fractures. Tibial nonunions constitute the majority of long bone nonunions seen by orthopaedic surgeons. In this article, we present our approach to the surgical treatment of noninfected tibial shaft nonunions.

METHODS

Between 2008 and 2014, 33 patients with aseptic diaphyseal tibial nonunion was treated by reamed intramedullary nailing and were retrospectively reviewed. The initial fracture management consisted of external fixation (27 patients), plate fixation (2 patients) and cast treatment (4 patients). All patients, preoperatively, were evaluated for the signs of the infection, by the same protocol. There were 13 hypertrophic, 16 oligotrophic (atrophic) and 4 defect nonunions registered in our material. The primary goal was to perform a closed intramedullary nailing on antegrade manner. An open procedure was only unavoidable when implants had to be removed or an osteotomy had to be performed to improve the alignment. Functional rehabilitation was encouraged with the assistance of a physiotherapist early postoperative. Patients were examined regularly during followed-up for a minimum of 12 months period for clinical and radiological signs of union, infection, malunion, malalignment, limb shortening, and implant failure.

RESULTS

The time that elapsed from injury to intramedullary nailing ranged from 9 months to 48 months (mean 17 months).Open intramedullary nailing was unavoidable in 25 cases (75,75%), while closed nailing was performed in 8 patients (24,25%). Osteotomy or resection of the fibula was performed in 78,8% of the cases. All patients were followed up in average period of 2 years postoperative (range 1-4 years), and 31(93,9%) patients achieved a solid union within the first 8 months. Mean union time was 5±0.8 months. Complications included 2 (6,06%) patients, one with deep infection and another case with absence of bone healing. Anatomical alignment has been achieved in the majority of patients, 28 patients (84,8%). The additionally autogenous bone chips were added in 4 patients (12,1%) where cortical defect was greater than 50% of the bone circumference.

CONCLUSION

In conclusion, a reamed intramedullary nail provides optimal conditions for stable fixation, good rotational control, adequate alignment, early weight-bearing and a high union rate of tibial non-unions. Reaming of the medullary canal with preservation of periosteal sleeve create the "breeding ground" for sound healing of tibial shaft nonunions. Additionally cancellous bone grafting is recommended only in the case of defect nonunion.

Effects of Episodic Alcohol Exposure on BMP2 Signaling During Tibia Fracture Healing

OBJECTIVES

To explore how alcohol affects the BMP-2 signaling pathway, which is known to play a critical role in bone and cartilage formation during fracture healing.

METHODS

A rat model was used to demonstrate the detrimental effects of alcohol exposure on tibia fracture healing. Specific components of the BMP-2 pathway were analyzed in fracture callus on days 3, 7, 14, and 21 after fracture via western immunoassays and enzyme-linked immunosorbent assay.

RESULTS

Alcohol exposure before tibia fracture demonstrated attenuation of downstream BMP-2 signaling. The BMP-2 antagonist, Chordin, may be the central component of the BMP-2-related changes demonstrated in this study. Although alcohol affected BMP-related proteins at all time points, it seems that day 14 after fracture is a critical time point for alcohol-related modulation of callus formation in our model.

CONCLUSIONS

This study may provide the scientific basis for further studies addressing whether the application of exogenous BMP-2 in patients with a history of alcohol abuse who sustain long bone fractures may or may not be of benefit.

Clinical Applications of Bone Tissue Engineering in Orthopedic Trauma

Purpose of Review

Orthopaedic trauma is a major cause of morbidity and mortality worldwide. Although many fractures tend to heal if treated appropriately either by nonoperative or operative methods, delayed or failed healing, as well as infections, can lead to devastating complications. Tissue engineering is an exciting, emerging field with much scientific and clinical relevance in potentially overcoming the current limitations in the treatment of orthopaedic injuries.

Recent Findings

While direct translation of bone tissue engineering technologies to clinical use remains challenging, considerable research has been done in studying how cells, scaffolds, and signals may be used to enhance acute fracture healing and to address the problematic scenarios of nonunion and critical-sized bone defects. Taken together, the research findings suggest that tissue engineering may be considered to stimulate angiogenesis and osteogenesis, to modulate the immune response to fractures, to improve the biocompatibility of implants, to prevent or combat infection, and to fill large gaps created by traumatic bone loss. The abundance of preclinical data supports the high potential of bone tissue engineering for clinical application, although a number of barriers to translation must first be overcome.

Summary

This review focuses on the current and potential applications of bone tissue engineering approaches in orthopaedic trauma with specific attention paid to acute fracture healing, nonunion, and critical-sized bone defects.

Alcohol exposure decreases osteopontin expression during fracture healing and osteopontin-mediated mesenchymal stem cell migration in vitro

BACKGROUND

Alcohol consumption is a risk factor for impaired fracture healing, though the mechanism(s) by which this occurs are not well understood. Our laboratory has previously shown that episodic alcohol exposure of rodents negatively affects fracture callus development, callus biomechanics, and cellular signaling which regulates stem cell differentiation. Here, we examine whether alcohol alters chemokine expression and/or signaling activity in the mouse fracture callus during early fracture healing.

METHODS

A mouse model for alcohol-impaired tibia fracture healing was utilized. Early fracture callus was examined for alcohol-effects on tissue composition, expression of chemokines involved in MSC migration to the fracture site, and biomechanics. The effects of alcohol on MSC migration and cell adhesion receptors were examined in an in vitro system.

RESULTS

Mice exposed to alcohol showed decreased evidence of external callus formation, decreased callus-related osteopontin (OPN) expression levels, and decreased biomechanical stiffness. Alcohol exposure decreased rOPN-mediated MSC migration and integrin β1 receptor expression in vitro.

CONCLUSIONS

The effects of alcohol exposure demonstrated here on fracture callus-associated OPN expression, rOPN-mediated MSC migration in vitro, and MSC integrin β1 receptor expression in vitro have not been previously reported. Understanding the effects of alcohol exposure on the early stages of fracture repair may allow timely initiation of treatment to mitigate the long-term complications of delayed healing and/or fracture non-union.

Outcomes of Presumed Aseptic Long-Bone Nonunions With Positive Intraoperative Cultures Through a Single-Stage Surgical Protocol

OBJECTIVE

To evaluate the outcomes of a single-stage surgical protocol to treat a presumed aseptic long-bone nonunion with positive intraoperative cultures obtained at the time of surgery.

DESIGN

Retrospective comparative series.

SETTING

Orthopaedic specialty hospital.

PATIENTS AND METHODS

We retrospectively identified 77 patients with long-bone nonunions thought to be aseptic preoperatively, which grew bacteria from cultures obtained at the time of index nonunion surgery.

INTERVENTION

Fifty (65%) patients underwent open debridement of the nonunion site followed by surgical stabilization through plates and screws. Twenty-seven (35%) patients underwent exchange nailing with canal reamings used for cultures.

MAIN OUTCOME MEASUREMENT

Rate of radiographic union, time to clinical and radiographic union, nonunion rate after index nonunion surgery, and final union rate after revision procedures.

RESULTS

Osseous union after the index nonunion surgery was achieved in 84% of the patients (65 of 77). Time to clinical union was 6.3 months (range, 1-24 months), and time to radiographic union was 7.4 months (range, 2-24 months). Eighteen percent (14 of 77 patients) did not heal after the index nonunion surgery and required additional surgeries. The final union rate after revision surgery was 99% (76 of 77 patients).

CONCLUSIONS

Eighty-four percent of presumed aseptic nonunions of long-bone fractures with positive intraoperative cultures fully healed after a single-stage surgical protocol and long-term antibiotic when appropriate. When patients are diagnosed with a subclinical infected nonunion, they should be counseled about the higher likelihood of reoperation, but in most cases can expect excellent union rates after 1 additional surgery.

LEVEL OF EVIDENCE

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

Pedicled iliac crest bone flap transfer for the treatment of upper femoral shaft fracture nonunion: An anatomic study and clinical applications

PURPOSE

We present the results of a study on the anatomy of the ascending branch of the lateral circumflex femoral artery (AB-LCFA) and the use of the pedicled iliac bone flap transfer perfused by AB-LCFA combined with external fixation for the treatment of the nonunion of upper femoral shaft fractures.

METHODS

The orientation, diameter, length, and distribution of the AB-LCFA from 40 lower limbs of adult cadavers were dissected and measured. From 2000 to 2012, 13 patients with nonunion of upper femoral shaft fractures underwent pedicled iliac bone flap transfer perfused by the AB-LCFA combined with external fixation. The time of bone fracture union was recorded based on X-ray examination. The functional results of the femoral shaft were evaluated by the Klemm classification.

RESULTS

The lateral circumflex femoral artery (LCFA) divided into ascending, transverse, and descending branches in 32 specimens (80%). The diameter of the AB-LCFA at the origin was 3.15 ± 0.9 mm and the length of the AB-LCFA was 8.51 ± 3.06 cm. The postoperative course of the procedure was uneventful in all 13 patients. The average follow-up was 15 months. Bone union was achieved in all patients and the average union time was 5.3 months. 12 patients achieved excellent or good functional results based on the Klemm classification.

CONCLUSION

The AB-LCFA has a consistent orientation and abundant blood flow. The transfer of the iliac crest bone flap perfused by the AB-LCFA while combined with external fixation could be an option for treating the nonunion of upper femoral shaft fractures.

Distraction osteogenesis reconstruction of large segmental bone defects after primary tumor resection: pitfalls and benefits

Successful cure is achieved in almost 70% of patients with primary bone sarcomas with currently available therapies. Some soft tissue sarcomas require wide bone resection in order to achieve appropriate margins for cure of disease, and patients undergoing these procedures need durable reconstruction. Biological reconstruction has been shown to provide patients with superior long-term results over other alternatives. Distraction osteogenesis is well studied in the correction of deformities as well as in addressing some congenital musculoskeletal pathologies. The use of this technique in tumor settings has been avoided by many surgeons for a multitude of concerns, including infection risk, potential tumor activation, and uncertainty regarding the effect of systemic therapy on the callus regenerate. We review the use of this reconstruction technique using cases from our institutional experience to illustrate its incorporation into the successful management of orthopedic oncology patients. Distraction osteogenesis is an effective method for reconstructing even large bony defects and is safe in the setting of systemic therapy. This technique has the potential to address some of the common problems associated with orthopedic oncology resection, such as infection and leg length discrepancy.

Percutaneous or Open Reduction of Closed Tibial Shaft Fractures During Intramedullary Nailing Does Not Increase Wound Complications, Infection or Nonunion Rates

OBJECTIVE

To compare the incidence of complications (wound, infection, and nonunion) among those patients treated with closed, percutaneous, and open intramedullary nailing for closed tibial shaft fractures.

DESIGN

Retrospective review.

SETTING

Multiple trauma centers.

PATIENTS

Skeletally mature patients with closed tibia fractures amenable to treatment with an intramedullary device.

INTERVENTION

Intramedullary fixation with closed, percutaneous, or open reduction.

MAIN OUTCOME MEASUREMENTS

Superficial wound complication, deep infection, nonunion.

RESULTS

A total of 317 tibial shaft fractures in 315 patients were included in the study. Two-hundred fractures in 198 patients were treated with closed reduction, 61 fractures in 61 patients were treated with percutaneous reduction, and 56 fractures in 56 patients were treated with formal open reduction. The superficial wound complication rate was 1% (2/200) for the closed group, 1.6% (1/61) for the percutaneous group, and 3.6% (2/56) for the open group with no statistical difference between the groups (P = 0.179). The deep infection rate was 2% (4/200) for the closed group, 1.6% (1/61) for the percutaneous group, and 7.1% (4/56) for the open group with no significant difference between the groups (P = 0.133). Nonunion rate was 5.0% (10/200) for the closed group, 4.9% (3/61) for the percutaneous group, and 7.1% (4/56) for the open group, with no statistical difference between the groups (P = 0.492).

CONCLUSIONS

This is the largest reported series of closed tibial shaft fractures nailed with percutaneous and open reduction. Percutaneous or open reduction did not result in increased wound complications, infection, or nonunion rates. Carefully performed percutaneous or open approaches can be safely used in obtaining reduction of difficult tibial shaft fractures treated with intramedullary devices.

LEVEL OF EVIDENCE

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

Radiological assessment of the PRF/BMSC efficacy in the treatment of aseptic nonunions: A retrospective study on 90 subjects

BACKGROUND

Nonunion is a major orthopaedic concern because of treatment difficulty, high costs and devastating effects on the patients' life quality. Therefore, there is interest in the use of bone substitutes and cell-based strategies to augment fracture repair. We aimed to verify if Platelet Rich Fibrin (PRF) added with bone marrow stromal cells (BMSC) was able to improve the reparative process in the aseptic nonunion, and to establish whether it was worthwhile with atrophic nonunion. The primary outcome was radiological union. As secondary endpoint, the healing time was assessed, and the radiological consolidation grade at each follow-up.

METHODS

We identified 113 subjects with tibia or femur nonunion and retrospectively created two groups. Group A was constituted by 56 subjects who underwent the standard procedure, i.e. Judet decortication with/out internal fixation devices, and opposite cortical homoplastic stick. In 57 patients, the standard procedure was modified by adding PRF and BMSC carried by homologous lyophilised bone chips (group B). The same surgeon performed all the operations. To our knowledge, no data are reported in the literature about such application. Since a "gold standard" for healing quantification does not exist, a new scoring radiological system was applied, at 1.5, 3, 6, 12 and 24 months after treatment.

RESULTS

At the final 24-month follow-up, the radiological union percentage was 94,12 in group B and 95,12% in group A. A decreased healing time was demonstrated in the presence of PRF/BMSC in comparison with the standard procedure. When we compared the radiological scores at each follow-up, we found that the PRF/BMSC combination significantly improved the consolidation grade at 1.5-, 3- and 6-month follow-up in femurs and at 1.5-month follow-up in tibiae. Furthermore, an improved consolidation grade was demonstrated in the atrophic subjects treated with adjuvants compared to atrophic patients treated with the standard procedure at 1.5-month follow-up.

CONCLUSIONS

This study supports the concept that the use of PRF/BMSC, during the standard procedure, is effective in shortening nonunion healing time. It could allow an early mobilization of patients, minimizing suffering, and could be an effective tool to reduce the health-care costs resulting from this issue.

LEVEL OF EVIDENCE

Therapeutic level III.

An Innovative Approach to the Repair of Distal Tibia Nonunion Using a Retrograde Buried Tibio-Talar-Calcaneal Nail: A Case Report

We report a case using retrograde tibial nailing as treatment of nonunion of a distal tibial osteotomy, which was performed as part of a complex reconstruction of distal tibial malunion with ankle arthritis. Although retrograde nailing has classically been used for tibial-talar-calcaneal arthrodesis, this method spares the subtalar joint. Preservation of some hindfoot motion by subtalar mobility allows for a decrease in the loss of function typically seen with tibial-talar-calcaneal arthrodesis.

The Current Perspectives of Stem Cell Therapy in Orthopedic Surgery

CONTEXT

Musculoskeletal injuries may be painful, troublesome, life limiting and also one of the global health problems. There has been considerable amount of interest during the past two decades to stem cells and tissue engineering techniques in orthopedic surgery, especially to manage special and compulsive injuries within the musculoskeletal system.

EVIDENCE ACQUISITION

The aim of this study was to present a literature review regarding the most recent progress in stem cell procedures and current indications in orthopedics clinical care practice. The Medline and PubMed library databases were searched for the articles related with stem cell procedures in the field of orthopedic surgery and additionally the reference list of each article was also included to provide a comprehensive evaluation.

RESULTS

Various sources of stem cells have been studied for orthopedics clinical care practice. Stem cell therapy has successfully used for major orthopedic procedures in terms of bone-joint injuries (fractures-bone defects, nonunion, and spinal injuries), osteoarthritis-cartilage defects, ligament-tendon injuries, femoral head osteonecrosis and osteogenesis imperfecta. Stem cells have also used in bone tissue engineering in combining with the scaffolds and provided faster and better healing of tissues.

CONCLUSIONS

Large amounts of preclinical studies have been made of stem cells and there is an increasing interest to perform these studies within the human population but preclinical studies are insufficient; therefore, much more and efficient studies should be conducted to evaluate the efficacy and safety of stem cells.

Extracorporeal shockwave therapy (ESWT) ameliorates healing of tibial fracture non-union unresponsive to conventional therapy

Tibial non-unions are common cause of demanding revision surgeries and are associated with a significant impact on patients' quality of life and health care costs. Extracorporeal shockwave therapy (ESWT) has been shown to improve osseous healing in vitro and in vivo. The main objective of present study was to evaluate the efficacy of ESWT in healing of tibial non-unions unresponsive to previous surgical and non-surgical measures. A retrospective multivariant analysis of a prospective open, single-centre, clinical trial of tibia non-union was conducted. 56 patients with 58 eligible fractures who met the FDA criteria were included. All patients received 3000-4000 impulses of electrohydraulic shockwaves at an energy flux density of 0.4mJ/mm(2) (-6dB). On average patients underwent 1.9 times (±1.3SD) surgical interventions prior to ESWT displaying the rather negatively selected cohort and its limited therapy responsiveness. In 88.5% of patients receiving ESWT complete bone healing was observed after six months irrespective of underlying pathology. The multivariant analysis showed that time of application is important for therapy success. Patients achieving healing received ESWT earlier: mean number of days between last surgical intervention and ESWT (healed - 355.1 days±167.4SD vs. not healed - 836.7 days±383.0SD; p<0.0001). ESWT proved to be a safe, effective and non-invasive treatment modality in tibial non-unions recalcitrant to standard therapies. The procedure is well tolerated, time-saving, lacking side effects, with potential to significantly decrease health care costs. Thus, in our view, ESWT should be considered the treatment of first choice in established tibial non-unions.

Dynamizations and Exchanges: Success Rates and Indications

OBJECTIVE

To characterize the timing, indications, and "success rates of secondary interventions, dynamization and exchange nailing, in a large series of tibial nonunions" (dynamization and exchange nailing are types of secondary interventions).

SETTING

Retrospective multicenter analysis from level 1 trauma hospitals.

PATIENTS

A total of 194 tibia fractures that underwent dynamization or exchange nailing for delayed/nonunion.

INTERVENTION

Records and radiographs to characterize demographic data, fracture type, and cortical contact after tibial nailing were gathered. The radiographic union score for tibias (RUST) and the timing of intervention and time to union were calculated.

MAIN OUTCOME MEASURES

The primary outcome was success of either intervention, defined as achieving union, with the need for further intervention defining failure. Other outcomes included RUST scores at intervention and union, and timing to intervention and union for both techniques. Two-tailed t tests and Fisher exact with P set at <0.05 for significance were used as indicated.

RESULTS

A total of 194 tibia fractures underwent dynamization (97) or exchange nailing (97). No statistical differences were found between groups with demographic characteristics. The presence of a fracture gap (P = 0.01) and comminuted fractures (P = 0.002) was more common in the exchange group. The success rates of the interventions and RUST scores were not different when performed before versus after 6 months; therefore, data were pooled. The RUST scores at the time of intervention were not different for successful or failed dynamizations (7.13 vs. 7.07, P = 0.83) or exchanges (6.8 vs. 7.3, P = 0.37). Likewise, the time to successful versus failed dynamization (165 vs. 158 days, P = 0.91) or exchange nailing (224 vs. 201 days, P = 0.48) was not different. No cortical contact or a gap was a statistically negative factor for both exchange nails (P = 0.09) and dynamizations (P = 0.06). When combined, the success in the face of a gap was 78% versus 92% when no gap was present (P = 0.02).

CONCLUSIONS

Previous literature has few reports of the success rates of secondary interventions for tibial nonunions. The indications for dynamization and exchange were similar. Comminuted fractures, and fractures with no cortical contact or "gap" present after intramedullary nailing, favored having an exchange nail performed over dynamization. Fracture gap was also found to be a negative prognostic factor for both procedures. Overall, this study demonstrates high rates of union for both interventions, making them both viable options.

LEVEL OF EVIDENCE

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

Single-Stage Treatment Protocol for Presumed Aseptic Diaphyseal Nonunion

Introduction

This article describes the general surgical technique for treating presumed diaphyseal nonunion with a one-stage procedure involving intraoperative removal of specimens for culture, revision open reduction and internal fixation (ORIF) with a plate or nail, and bone-grafting.

Step 1 Preoperative Evaluation

Take a careful history, evaluate the extremity and wound, and note comorbidities and medications.

Step 2 Preoperative Planning

Preoperative planning is essential before revision nonunion surgery.

Step 3 Debridement Implant Removal and Cultures

Debride the nonunion site, remove all failed and loose implants, and take specimens for culture; withhold antibiotics until all culture specimens have been obtained.

Step 4 Open Reduction and Internal Fixation

Reduce the fracture and use interfragmentary fixation and/or compression, or a bridging plate.

Step 5 Postoperative Care

If any of the five cultures are positive, consult an infectious disease specialist with experience in treating musculoskeletal infections.

Results

We have used this protocol at our institution for patients with prior fracture surgery who subsequently developed a nonunion, with or without implant failure, that had no obvious infectious etiology.IndicationsContraindicationsPitfalls & Challenges.

Treatment of hypertrophic distal tibia nonunion and early malunion with callus distraction

BACKGROUND

Hypertrophic nonunions and early malunions of pilon and distal tibia fractures result in complex, challenging to treat deformities. Callus distraction histiogenesis is an option for their management, allowing for the simultaneous correction of multiplanar deformity and limb length discrepancy.

METHODS

A single-surgeon, retrospective case series was performed. Eight patients (6 males and 2 females) who were treated with callus distraction from 1991 to 2011 were reviewed. Six of 8 patients had varus deformities (range, 8-19 degrees) and 2 patients had valgus deformities (both 16 degrees) of the distal tibia metaphysis. Six of 8 had apex anterior deformities (range, 2-21 degrees) and 2 had apex posterior deformity (range, 9-20 degrees). An Ilizarov fixator or Taylor Spatial Frame (Smith & Nephew, Memphis, TN) was used to distract the nonunion or early malunion to correct alignment and shortening. Preoperative and postoperative radiographic outcomes, limb alignment, and ankle-hindfoot scores were reviewed.

RESULTS

Union was achieved in all patients at a mean of 5.8 months (range, 4.1-7.6 months). The 3 patients treated with an Ilizarov-type fixator had deformity correction to within 5 degrees of neutral in 1 plane and to within 10 degrees in the other plane. All 5 patients treated with a Taylor Spatial Frame had correction to within 5 degrees of neutral alignment in both coronal and sagittal planes. There were 2 complications requiring reoperation and 1 persistent limb length discrepancy (2 cm) after treatment. Median AOFAS ankle-hindfoot score was 82.5 (range, 53-90) at an average follow-up of 30.4 months (range, 8-92).

CONCLUSIONS

Callus distraction histiogenesis was a minimally invasive technique that can successfully treat patients with hypertrophic nonunion and early malunion of the distal tibia. We believe the application of a computer-assisted 6-axis frame to correct the deformity improved the correction of these multiplanar deformities.

LEVEL OF EVIDENCE

Level IV, case series.

Bone fracture healing: cell therapy in delayed unions and nonunions

Bone fracture healing impairment related to mechanical problems has been largely corrected by advances in fracture management. Better protocols, more strict controls of time and function, and hardware and surgical technique evolution have contributed to better prognosis, even in complex fractures. However, atrophic nonunion persists in clinical cases where, for different reasons, the osteogenic capability is impaired. When this is the case, a better understanding of the basic mechanisms under bone repair and augmentation techniques may put in perspective the current possibilities and future opportunities. Among those, cell therapy particularly aims to correct this insufficient osteogenesis. However, the launching of safe and efficacious cell therapies still requires substantial amount of research, especially clinical trials. This review will envisage the current clinical trials on bone healing augmentation based on cell therapy, with the experience provided by the REBORNE Project, and the insight from investigator-driven clinical trials on advanced therapies towards the future. This article is part of a Special Issue entitled Stem Cells and Bone.

A single-stage treatment protocol for presumptive aseptic diaphyseal nonunions: a review of outcomes

OBJECTIVE

To review the results of a single-stage treatment protocol for presumptive aseptic diaphyseal nonunion with a well-healed wound and no infection history.

DESIGN

Retrospective comparative study.

SETTING

Tertiary referral center.

PATIENTS AND METHODS

We retrospectively reviewed all presumptive aseptic diaphyseal nonunions treated by a single-stage protocol. There were 104 patients who met the inclusion criteria. Eighty-seven patients were available for follow-up through to complete healing (83.7% follow-up rate).

INTERVENTION

The protocol entails withholding preoperative antibiotics, removing the implant, performing open debridement or canal reaming, taking 5 cultures of the nonunion site or canal reamings, followed by antibiotic administration, and revision open reduction and internal fixation or exchange nailing. If intraoperative cultures are positive, long-term antibiotics are begun specific to organism sensitivities.

MAIN OUTCOME MEASUREMENTS

To analyze the rate of positive cultures and to compare the rate of secondary surgery to promote healing in positive and negative culture groups.

RESULTS

Intraoperative cultures were positive in 28.7% (25/87) of patients with complete follow-up. The overall rate of secondary surgery for persistence of nonunion was 12.6% (11/87). In patients with positive intraoperative cultures, rate of secondary surgery was 28% (7/25) versus 6.4% (4/62) in the group without positive intraoperative cultures (P = 0.01).

CONCLUSION

A single-stage treatment protocol for presumptive aseptic diaphyseal nonunions was effective in obviating further revision surgery in 93.6% of truly aseptic cases and in 72% of positive culture cases and is still employed at our institution.

Outcomes and complication rates of different bone grafting modalities in long bone fracture nonunions: a retrospective cohort study in 182 patients

BACKGROUND

Novel bone substitutes have challenged the notion of autologous bone grafting as the 'gold standard' for the surgical treatment of fracture nonunions. The present study was designed to test the hypothesis that autologous bone grafting is equivalent to other bone grafting modalities in the management of fracture nonunions of the long bones.

METHODS

A retrospective review of patients with fracture nonunions included in two prospective databases was performed at two US level 1 trauma centers from January 1, 1998 (center 1) or January 1, 2004 (center 2), respectively, until December 31, 2010 (n = 574). Of these, 182 patients required adjunctive bone grafting and were stratified into the following cohorts: autograft (n = 105), allograft (n = 38), allograft and autograft combined (n = 16), and recombinant human bone morphogenetic protein-2 (rhBMP-2) with or without adjunctive bone grafting (n = 23). The primary outcome parameter was time to union. Secondary outcome parameters consisted of complication rates and the rate of revision procedures and revision bone grafting.

RESULTS

The autograft cohort had a statistically significant shorter time to union (198 ± 172-225 days) compared to allograft (416 ± 290-543 days) and exhibited a trend towards earlier union when compared to allograft/autograft combined (389 ± 159-619 days) or rhBMP-2 (217 ± 158-277 days). Furthermore, the autograft cohort had the lowest rate of surgical revisions (17%) and revision bone grafting (9%), compared to allograft (47% and 32%), allograft/autograft combined (25% and 31%), or rhBMP-2 (27% and 17%). The overall new-onset postoperative infection rate was significantly lower in the autograft group (12.4%), compared to the allograft cohort (26.3%) (P < 0.05).

CONCLUSION

Autologous bone grafting appears to represent the bone grafting modality of choice with regard to safety and efficiency in the surgical management of long bone fracture nonunions.

Development of composite scaffolds for load-bearing segmental bone defects

The need for a suitable tissue-engineered scaffold that can be used to heal load-bearing segmental bone defects (SBDs) is both immediate and increasing. During the past 30 years, various ceramic and polymer scaffolds have been investigated for this application. More recently, while composite scaffolds built using a combination of ceramics and polymeric materials are being investigated in a greater number, very few products have progressed from laboratory benchtop studies to preclinical testing in animals. This review is based on an exhaustive literature search of various composite scaffolds designed to serve as bone regenerative therapies. We analyzed the benefits and drawbacks of different composite scaffold manufacturing techniques, the properties of commonly used ceramics and polymers, and the properties of currently investigated synthetic composite grafts. To follow, a comprehensive review of in vivo models used to test composite scaffolds in SBDs is detailed to serve as a guide to design appropriate translational studies and to identify the challenges that need to be overcome in scaffold design for successful translation. This includes selecting the animal type, determining the anatomical location within the animals, choosing the correct study duration, and finally, an overview of scaffold performance assessment.

Muscle: a source of progenitor cells for bone fracture healing

Bone repair failure is a major complication of open fracture, leading to non-union of broken bone extremities and movement at the fracture site. This results in a serious disability for patients. The role played by the periosteum and bone marrow progenitors in bone repair is now well documented. In contrast, limited information is available on the role played by myogenic progenitor cells in bone repair. In a recent article published in BMC Musculoskeletal Disorders, Liu et al. compared the presence of myogenic progenitor (MyoD lineage cells) in closed and open fractures. They showed that myogenic progenitors are present in open, but not closed fractures, suggesting that muscle satellite cells may colonize the fracture site in the absence of intact periosteum. Interestingly, these progenitors sequentially expressed a chondrogenic and, thereafter, an osteoblastic phenotype, suggestive of a functional role in the repair process. This finding opens up new perspectives for the research of orthopedic surgical methods, which could maximize myogenic progenitor access and mobilization to augment bone repair. Please see related article: http://www.biomedcentral.com/1471-2474/12/288.