Treatment of large segmental bone defects with reamer-irrigator-aspirator bone graft: technique and case series

Hemorrhagic-Induced Cardiovascular Complications During Reamer-Irrigator-Aspirator-Assisted Femoral Nonunion Treatment

The reamer-irrigator-aspirator (RIA) is a device that has recently been developed to retrieve bone graft from the medullary canal of the femur and the tibia. As for most new surgical procedures, complications arise as part of the learning curve and/or imperfections in the design or technique. To increase awareness of potential complications and to prevent unnecessary harm to the patient, new complications need to be reported. We present case reports of 2 patients who developed severe intraoperative cardiac events presumably caused by excessive and rapid blood loss during RIA bone graft harvesting. This complication has not been described before. Increased awareness of excessive blood loss and subsequent cardiac events during an RIA procedure is warranted.

LEVEL OF EVIDENCE

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

Zahid, Khan AH, Sherwani MKA, Khan AQ. Management of traumatic tibial diaphyseal bone defect by "induced-membrane technique"

BACKGROUND

Gap nonunion of long bones is a challenging problem, due to the limitation of conventional reconstructive techniques more so if associated with infection and soft tissue defect. Treatment options such as autograft with non-vascularized fibula and cancellous bone graft, vascularized bone graft, and bone transportation are highly demanding on the part of surgeons and hospital setups and have many drawbacks. This study aims to analyze the outcome of patients with wide diaphyseal bone gap treated with induced-membrane technique (Masquelet technique).

MATERIALS AND METHODS

This study included 9 patients (7 males and 2 females), all with tibial bone-gap. Eight of the 9 patients were infected and in 3 patients there was associated large soft tissue defect requiring flap cover. This technique is two-stage procedure. Stage I surgery included debridement, fracture stabilization, application of spacer between bone ends, and soft tissue reconstruction. Stage II surgery included removal of spacer with preservation of induced membrane formed at spacer surface and filling the bone-gap with morselized iliac crest bone-graft within the membrane sleeve. Average bone-gap of 5.2 cm was treated. The spacer was always found to be encapsulated by a thick glistening membrane which did not collapse after its removal. All patients were followed up for an average period of 21.5 months.

RESULTS

Serial Radiographs showed regular uptake of autograft and thus consolidation within themselves in the region of bone gap and also with host bone. Bone-union was documented in all patients and all patients are walking full weight-bearing without support.

CONCLUSIONS

The study highlights that the technique provide effective and practical management for difficult gap nonunion. It does not require specialized equipment, investigations, and surgery. Thus, it provides a reasonable alternative to the developing infrastructures and is a reliable and reproducible technique.

Bone Grafting: Sourcing, Timing, Strategies, and Alternatives

Acute fractures, nonunions, and nonunions with bone defects or osteomyelitis often need bone graft to facilitate union. There are several factors to consider when it is determined that a bone graft is needed. These factors include the source of the bone graft (autograft vs. allograft), proper timing for placement of the bone graft, strategies to avoid further complications (particularly in the setting of osteomyelitis), and with the development of a variety of bone graft substitutes, whether alternatives to autograft are available and appropriate for the task at hand. Autograft bone has commonly been referred to as the "gold standard" of bone grafts, against which the efficacy of other grafts has been measured. The best timing for when to place a bone graft or substitute is also somewhat controversial, particularly after an open fracture or a potentially contaminated bed. The treatment of infected nonunions, particularly those that require a graft to facilitate healing, can be quite challenging. Typically, the infection is completely eradicated before placement of a bone graft, but achieving a sterile bed and the timing of a bone graft require strategic thinking and planning. This review outlines the benefits of autografts, the most suitable sites for harvesting bone grafts, the timing of bone graft procedures, the potential risks and benefits of grafting in the face of infection, and the currently available bone graft extenders.

The Masquelet technique of induced membrane for healing of bone defects. A review of 8 cases

BACKGROUND

Segmental defects of long bones are notoriously difficult to treat. This study evaluates eight cases in which the Masquelet technique of induced membranes was used. The primary purpose was to assess the results compared to other types of bone reconstruction and share our tips and tricks to improve the outcome.

METHOD

Retrospective study based on patient records and radiographs. Eight patients operated between 2011 and 2014 were included. Three had infected non-unions. Outcome measures were time-to full weight-bearing, time to radiographic consolidation, need for secondary bone grafting procedures and occurrence of complications.

RESULTS

Time to full weight bearing seemed shorter in patients treated with nails. In two cases only partial radiographic consolidation was noted at the latest follow up visit. One patient needed secondary bone grafting and two limbs were malaligned. There were no amputations, no persistent infections, and no implant failures.

DISCUSSION

The induced membrane technique is a useful tool to substitute bone loss yet consolidation time is somewhat unpredictable and prolonged non-weight bearing is required.

CONCLUSION

Nailing seems to improve outcome compared to plating. It shortens treatment time, reduces the amount of bone graft needed, aligns the bone and should be considered when feasible. Further larger scale studies are welcome to throw more light into the efficacy and effectiveness of this technique.

Treatment of Bone Loss With the Induced Membrane Technique: Techniques and Outcomes

OBJECTIVES

To critically review the outcomes and issues associated with the induced membrane technique in a trauma population.

DESIGN

Retrospective case series, Level IV therapeutic study.

SETTING

Urban Level I trauma center.

PATIENTS

Sixty-nine patients aged 18 years or older who underwent treatment of bone loss with the induced membrane technique.

INTERVENTION

All patients underwent open treatment of their traumatic bone loss with a 2-stage induced membrane technique.

MAIN OUTCOME MEASUREMENT

Bony union rate, as evaluated with radiographic and clinical signs of healing.

RESULTS

Patients in this series averaged 4.4 surgeries, which included initial debridement to definitive fixation. The tibia was the most common site of bone loss, encompassing 50.7% of the series, whereas femoral bone loss was next at 24.6%. Polymethylmethacrylate spacers were in place for a mean of 11.2 weeks (mode of 8 weeks) before bone grafting for an average bony defect volume of 76.6 cm. Union was obtained in 82.6% of patients at a mean of 26.6 weeks after grafting. Mean follow-up for these patients was 23.8 months.

CONCLUSIONS

The induced membrane technique is an effective method to obtain bony union when used in the trauma population. However, it is not foolproof, and attention must be paid to the critical subtleties of the procedure. Further investigation is needed to help determine the optimal spacer composition and other technical aspects of the procedure such as timing of the exchange.

LEVEL OF EVIDENCE

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

Reamer Irrigator Aspirator bone graft harvesting: complications and outcomes in an Asian population

INTRODUCTION

Autologous bone grafting has been accepted as the gold standard in the treatment of non-unions and in definitive filling of segmental bone defects. However, there have been well-recognised complications associated with their harvest. The Reamer Irrigator Aspirator (RIA) system is an alternative technique of autologous bone graft harvesting. Studies have been published in the Western population showing the efficacy and outcome of this technique. No prior studies were done in the Asian population, who has smaller average canals, different femoral geometry as compared to Caucasians and weaker bone density in both genders. We aim to present the findings and discuss its suitability in the Asian population when dealing with segmental bone loss and non-unions requiring reconstruction.

METHODS

We conducted a retrospective analysis of all trauma patients with segmental bone loss and non-unions treated with RIA bone grafting over a 4.5 year period. A total of 57 cases of RIA bone grafting were conducted on 53 patients. The amount of bone graft harvested, blood loss and post-operative pain were measured. Patients were followed up for union rate as well as complications of the procedure.

RESULTS

Union was achieved in 86.8% of patients. The mean time to union was 17.64 weeks. Seven patients did not achieve union after the first RIA surgery, in which six of seven were open fractures initially and six were smokers. One major intra-operative complication was recorded, that being a fractured femoral shaft due to thinning of the cortex by the RIA harvester. There were two patients who developed donor site superficial soft tissue infection that resolved after a course of antibiotics. There were no long-term complications seen in all patients.

CONCLUSIONS

The safety and efficacy of RIA bone graft harvesting for the management of non-union in the Asian population is promising, with adequate graft quantities, high success and low complication rates that are comparable to the Caucasian population. The diameter of the medullary canal in our population is suitable for this procedure. We believe that RIA bone graft harvesting provides a reliable and safe alternative source of autologous bone grafts for bone grafting of non-union sites.

Retrograde Versus Antegrade Femoral Bone Graft Harvesting Using the Reamer-Irrigator-Aspirator

OBJECTIVES

To compare retrograde versus antegrade femoral bone graft harvesting using the reamer-irrigator-aspirator system to determine whether there was any difference in intraoperative, postoperative, or patient outcome variables.

DESIGN

Retrospective cohort study.

SETTING

Urban Level I Trauma Center.

PATIENTS/PARTICIPANTS

Ninety-four (62 antegrade and 32 retrograde procedures) consecutive adult patients who underwent femoral autologous bone graft harvesting using the Synthes reamer-irrigator-aspirator system between April 2008 and March 2013.

MAIN OUTCOME MEASUREMENTS

Amount of bone graft, perioperative fractures or other complications, and postoperative hip and/or knee pain.

RESULTS

There was no significant difference between demographic or medical comorbidities between the groups. There was no significant difference in the side of the graft harvest, graft volume, hospital length of stay, or the ability to ambulate on postoperative day 1. There was a significantly increased incidence of iatrogenic fracture or prophylactic nailing with antegrade reaming (4 vs. 0, P = 0.01). Average length of follow-up was 500 (range, 20-1477) days for the antegrade group and 378 (range, 19-706) days for the retrograde group. The antegrade group had a nonsignificant increased incidence of hip pain (8.1% vs. 3.1%, P = 0.66), and the retrograde group had a significantly higher incidence of knee pain (15.6% vs. 1.6%, P = 0.02) at 6-month follow-up. Neither hip nor knee complaints were present at final follow-up. No cases of delayed femur fracture, infection, or abductor and/or antalgic gait involving the donor extremity were seen at final follow-up.

CONCLUSIONS

This study provides support to the safety of femoral bone graft harvesting using both antegrade and retrograde techniques. Both techniques provide reliable, high-volume, nonstructural autologous bone graft with minimal associated morbidity.

LEVEL OF EVIDENCE

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

Comparative study of membranes induced by PMMA or silicone in rats, and influence of external radiotherapy

The induced membrane technique has been used for long bone defect reconstruction after traumatism. One of the major drawbacks of this method is the difficult removal of the polymethyl methacrylate spacer after membrane formation. We therefore replaced the stiff PMMA spacer with a semi-flexible medical grade silicone spacer. This study aimed to compare subcutaneously formed membranes, induced by PMMA and silicone, in the irradiated or not irradiated areas within 28 rats that received the spacers. Histological analysis was performed to evaluate the composition of the membrane and to quantify the amount of vessels. Histomorphometric measurements were used to evaluate membranes' thickness, while fibrosis and inflammation were scored. The expression of VEGF and BMP-2 in lysates of the crushed membranes was determined by Western blotting. ALP expression was analyzed in HBMSC cultures in contact with the same lysates. Non-irradiated membranes induced by the two spacer types were non-inflammatory, fibrous and organized in layers. Irradiation did not change the macroscopic properties of membranes that were induced by silicone, while PMMA induced membranes were sensitive to the radiotherapy, resulting in thicker, strongly inflammatory membranes. Irradiated membranes showed an overall reduced osteogenic potential. Medical grade silicone is safe for the use in radiotherapy and might therefore be of great advantage for patients in need of cancer treatment.

Advanced concepts in knee arthrodesis

The aim is to describe advanced strategies that can be used to diagnose and treat complications after knee arthrodesis and to describe temporary knee arthrodesis to treat infected knee arthroplasty. Potential difficult complications include nonunited knee arthrodesis, limb length discrepancy after knee arthrodesis, and united but infected knee arthrodesis. If a nonunited knee arthrodesis shows evidence of implant loosening or failure, then bone grafting the nonunion site as well as exchange intramedullary nailing and/or supplemental plate fixation are recommended. If symptomatic limb length discrepancy cannot be satisfactorily treated with a shoe lift, then the patient should undergo tibial lengthening over nail with a monolateral fixator or exchange nailing with a femoral internal lengthening device. If a united knee arthrodesis is infected, the nail must be removed. Then the surgeon has the option of replacing it with a long, antibiotic cement-coated nail. The authors also describe temporary knee arthrodesis for infected knee arthroplasty in patients who have the potential to undergo insertion of a new implant. The procedure has two goals: eradication of infection and stabilization of the knee. A temporary knee fusion can be accomplished by inserting both an antibiotic cement-coated knee fusion nail and a static antibiotic cement-coated spacer. These advanced techniques can be helpful when treating difficult complications after knee arthrodesis and treating cases of infected knee arthroplasty.

Incidence of donor site morbidity following harvesting from iliac crest or RIA graft

INTRODUCTION

Clinical management of non-union of long bone fractures and segmental bone defect is a challenge for orthopaedic surgeons. The use of autologous bone graft (ABG) is always considered the gold standard treatment. Traditional techniques for harvesting ABG from iliac crest usually involve several complications, particularly at the donor site. The Reamer-Irrigator-Aspirator (RIA) is an intramedullary reaming system that generates a large volume of cancellous bone material in a single-step reaming process; this bone material can be collected and potentially used as an ABG source. Our interest is to compare the complications associated with the standard technique of harvesting from iliac crest with those of the innovative RIA harvesting device.

MATERIALS AND METHODS

A database of 70 patients with long bone non-unions was studied. The patients were divided into two groups according to the surgical harvesting technique used: RIA system ABG (35 patients) and iliac crest ABG (35 patients).

RESULTS

At the 12-month follow-up, pain at the donor site was reported in no patients in the RIA system ABG group and five of 35 patients (14.28%) in the iliac crest ABG group. Local infections at the donor site were found in no patients in the RIA system ABG group compared with five patients (14.28%) in the iliac crest ABG group. There were no fractures in the RIA system ABG group and one case (2.85%) of anterior superior iliac spine (ASIS) dislocation in the iliac crest ABG group. No systemic infections were detected in either group.

DISCUSSION

We analysed the scientific literature on the use of RIA technique to collect ABG for use in patients with anthropic-oligotrophic non-unions, with a focus on the complications associated with this technique.

CONCLUSION

RIA bone graft for the treatment of non-unions and segmental bone defect of long bones seems to be a safe and efficient procedure with low donor site morbidity.

Management of traumatic bone loss in the lower extremity

Segmental bone loss represents a difficult clinical entity for the treating orthopedic surgeon. This article discusses the various treatment modalities available for limb reconstruction, with a focus on the indications, potential complications, and the outcomes of available treatment options.

Sequential harvesting of bone graft from the intramedullary canal of the femur

The effectiveness of using the Reamer/Irrigator/Aspirator (RIA) System (Synthes, Inc, West Chester, Pennsylvania) to obtain bone graft from the intramedullary canal of long bones for the treatment of bone defects and nonunions has been previously documented. However, there is nothing in the literature discussing the potential for reaming the same canal at subsequent surgeries. The authors detail their experience of 8 instances of sequential reaming in 7 patients. Six patients were harvested twice, and 1 patient was harvested 3 times. In each patient, the bone graft was obtained from the same canal. The main outcome measurements were time interval between reamings, reamer head size, indication for reaming, volume of harvested bone graft, and complications. Average volume of graft obtained in the first reaming procedure was 34 mL (range, 25-50 mL). After an average of 9 months (range, 3-16 months), the subsequent reaming was performed. Average volume of graft obtained in the second procedure was 45 mL (range, 28-65 mL). In the authors' series, no reaming-related complications were observed. The graft volume was the same or increased during the subsequent intramedullary reaming in all but 1 case, suggesting that the intramedullary canal is a potentially renewable source for bone graft. There were no complications related to the sequential reaming procedure. Overall, the authors' data suggest that sequential reaming with the RIA has the potential to safely and effectively provide a large quantity of bone graft on multiple occasions.

Bone tissue engineering and regenerative medicine: targeting pathological fractures

Patients with bone diseases have the highest risk of sustaining fractures and of suffering from nonunion bone healing due to tissue degeneration. Current fracture management strategies are limited in design and functionality and do not effectively promote bone healing within a diseased bone environment. Fracture management approaches include pharmaceutical therapy, surgical intervention, and tissue regeneration for fracture prevention, fracture stabilization, and fracture site regeneration, respectively. However, these strategies fail to accommodate the pathological nature of fragility fractures, leading to unwanted side effects, implant failures, and nonunions. To target fragility fractures, fracture management strategies should include bioactive bone substitutes designed for the pathological environment. However, the clinical outcome of these materials must be predictable within various disease environments. Initial development of a targeted treatment strategy should focus on simulating the physiological in vitro bone environment to predict clinical effectiveness of the engineered bone. An in vitro test system can facilitate reduction of implant failures and non-unions in fragility fractures.

Masquelet technique for treatment of posttraumatic bone defects

Masquelet technique, which is the use of a temporary cement spacer followed by staged bone grafting, is a recent treatment strategy to manage a posttraumatic bone defect. This paper describes a series of 9 patients treated with this technique of staged bone grafting following placement of an antibiotic spacer to successfully manage osseous long bone defects. The injured limbs were stabilized and aligned at the time of initial spacer placement. In our series, osseous consolidation was successfully achieved in all cases. This technique gives promising result in the management of posttraumatic bone defects.

More adverse events than expected in the outcome after use of the reamer-irrigator-aspirator

PURPOSE

The reamer-irrigator-aspirator (RIA) system is described as having high success rates and only few complications. The RIA was originally designed to ream the intramedullary canal in a single step prior to the placement of an intramedullary nail for femur fixation. Its purpose was to collect and evacuate marrow contents during reaming to prevent embolism into the systemic circulation. Marrow evacuation is also used to stimulate healing in nonunion fractures, segmental bone defects, and osteomyelitis. Despite the described success rates, we experienced severe adverse events. Our aim was to describe these events and point out possible complications.

METHODS

A retrospective study of all consecutive patients treated for nonunion fractures, bone defects, or osteomyelitis from October 2007 to March 2010. All patients were treated with the RIA system. We analyzed demographic characteristics, consolidation on X-rays, time from injury to healing, complications, and postoperative pain caused by the reaming procedure.

RESULTS

We included 32 patients (21 males) with an average follow-up of 277 days. Successful healing was achieved in 66 % of all patients, and 18 % suffered from postoperative pain. A complication due to the use of the RIA system was registered in 31 % of the patients. Recorded complications were bone defects, signs of lung embolism, a myocardial infarction, and fissure fractures.

CONCLUSIONS

The RIA system has benefits in the treatment of nonunion and osteomyelitis defect, but is not without risk. Meticulous surgical technique is mandatory and peroperative constant monitoring of patients and the assembled device is mandatory.

Donor site morbidity with reamer-irrigator-aspirator (RIA) use for autogenous bone graft harvesting in a single centre 204 case series

Donor site morbidity and complication rate using the reamer-irrigator-aspirator (RIA) system for intramedullary, non-structural autogenous bone graft harvesting were investigated in a retrospective chart and radiographic review at a University affiliated Level-1 Trauma Centre. 204 RIA procedures in 184 patients were performed between 1/1/2007 and 12/31/2010. RIA-indication was bone graft harvesting in 201 (98.5%), and intramedullary irrigation and debridement in 3 (1.5%) cases. Donor sites were: femur - antegrade 175, retrograde 4, tibia - antegrade 7, retrograde 18. Sixteen patients had undergone two RIA procedures, two had undergone three procedures, all using different donor sites. In 4 cases, same bone harvesting was done twice. Mean volume of bone graft harvested was 47 ± 22ml (20-85 ml). The complication rate was 1.96% (N=4). Operative revisions included 2 retrograde femoral nails for supracondylar femur fractures 6 and 41 days postoperatively (antegrade femoral RIA), 1 trochanteric entry femoral nail (subtrochanteric fracture) 17 days postoperatively (retrograde femoral RIA) and 1 prophylactic stabilization with a trochanteric entry femoral nail for intraoperative posterior femoral cortex penetration without fracture. In our centre, the RIA technique has a low donor site morbidity and has been successfully implemented for harvesting large volumes of nonstructural autogenous bone graft.

Bone Regeneration Based on Tissue Engineering Conceptions - A 21st Century Perspective

The role of Bone Tissue Engineering in the field of Regenerative Medicine has been the topic of substantial research over the past two decades. Technological advances have improved orthopaedic implants and surgical techniques for bone reconstruction. However, improvements in surgical techniques to reconstruct bone have been limited by the paucity of autologous materials available and donor site morbidity. Recent advances in the development of biomaterials have provided attractive alternatives to bone grafting expanding the surgical options for restoring the form and function of injured bone. Specifically, novel bioactive (second generation) biomaterials have been developed that are characterised by controlled action and reaction to the host tissue environment, whilst exhibiting controlled chemical breakdown and resorption with an ultimate replacement by regenerating tissue. Future generations of biomaterials (third generation) are designed to be not only osteoconductive but also osteoinductive, i.e. to stimulate regeneration of host tissues by combining tissue engineering and in situ tissue regeneration methods with a focus on novel applications. These techniques will lead to novel possibilities for tissue regeneration and repair. At present, tissue engineered constructs that may find future use as bone grafts for complex skeletal defects, whether from post-traumatic, degenerative, neoplastic or congenital/developmental "origin" require osseous reconstruction to ensure structural and functional integrity. Engineering functional bone using combinations of cells, scaffolds and bioactive factors is a promising strategy and a particular feature for future development in the area of hybrid materials which are able to exhibit suitable biomimetic and mechanical properties. This review will discuss the state of the art in this field and what we can expect from future generations of bone regeneration concepts.

pHEMA-nHA encapsulation and delivery of vancomycin and rhBMP-2 enhances its role as a bone graft substitute

BACKGROUND

Bone grafts are widely used in orthopaedic procedures. Autografts are limited by donor site morbidity while allografts are known for considerable infection and failure rates. A synthetic composite bone graft substitute poly(2-hydroxyethyl methacrylate)-nanocrystalline hydroxyapatite (pHEMA-nHA) was previously developed to stably press-fit in and functionally repair critical-sized rat femoral segmental defects when it was preabsorbed with a single low dose of 300 ng recombinant human bone morphogenetic protein-2/7 (rhBMP-2/7).

QUESTIONS/PURPOSES

To facilitate clinical translation of pHEMA-nHA as a synthetic structural bone graft substitute, we examined its ability to encapsulate and release rhBMP-2 and the antibiotic vancomycin.

METHODS

We analyzed the compressive behavior and microstructure of pHEMA-nHA as a function of vancomycin incorporation doses using a dynamic mechanical analyzer and a scanning electron microscope. In vitro release of vancomycin was monitored by ultraviolet-visible spectroscopy. Release of rhBMP-2 from pHEMA-nHA-vancomycin was determined by ELISA. Bioactivity of the released vancomycin and rhBMP-2 was examined by bacterial inhibition and osteogenic transdifferentiation capabilities in cell culture, respectively.

RESULTS

Up to 4.8 wt% of vancomycin was incorporated into pHEMA-nHA without compromising its structural integrity and compressive modulus. Encapsulated vancomycin was released in a dose-dependent and sustained manner in phosphate-buffered saline over 2 weeks, and the released vancomycin inhibited Escherichia coli culture. The pHEMA-nHA-vancomycin composite released preabsorbed rhBMP-2 in a sustained manner over 8 days and locally induced osteogenic transdifferentiation of C2C12 cells in culture.

CONCLUSIONS

pHEMA-nHA can encapsulate and deliver vancomycin and rhBMP-2 in a sustained and localized manner with reduced loading doses.

CLINICAL RELEVANCE

The elasticity, osteoconductivity, and rhBMP-2/vancomycin delivery characteristics of pHEMA-nHA may benefit orthopaedic reconstructions or fusions with enhanced safety and efficiency and reduced infection risk.

Management of large segmental tibial defects using locking IM nail and absorbable mesh

Tibia accounts for the majority of open fractures with long segmental defects. The management of such defects imposes several challenges due to their associations with extensive soft tissue damage and high infection risk. In this report, we describe a new technique for the reconstruction of tibia in a young patient with 10 cm defect. The patient had a history of Gustilo Anderson type IIIB open fracture following a motorcycle accident. He was initially managed with multiple debridements and application of an external fixator. The defect was treated with the insertion of an antibiotic-coated intramedullary nail along with posterolateral bone grafting using an absorbable mesh. Six months postoperative, radiological assessment showed excellent callus formation diffusely around the intramedullary nail along with optimal alignment. The preliminary follow-up data are quite encouraging and the technique described in our case can be considered as a reasonable option in managing long segmental bone defects.

Bone propeller flap: a staged procedure

The ideal reconstruction technique for complex defects of the lower limb consists of replacing tissue with similar tissue in an attempt to achieve a good functional result. A 23-year-old white male sustained a crush injury with a grade IIIB open ankle dislocation. After open reduction and fixation, the patient developed severe osteomyelitis at the tibiotalar joint requiring a staged and radical debridement with a substantial combined soft tissue and bony defect over the distal tibia, fibula, and talus area. The reconstructive approach consisted of a modified model of the propeller flap, implementing the spare part concept in a 2-stage procedure using a prefabricated and vascularized "double-barrel" fibular graft. At 17 months postoperatively, a plain radiograph showed bony union with complete and stable coverage of the soft tissue defect. The patient was fully weightbearing. In conclusion, there is evidence to suggest that the established concept of a soft tissue propeller flap can be implemented on bone.

The use of Reamer Irrigator Aspirator (RIA) autograft harvest in the treatment of critical-sized iliac wing defects in sheep: investigation of dexamethasone and beta-tricalcium phosphate augmentation

Bone grafts are commonly used for the treatment of segmental bone defects and fracture non-unions. Recently, osseous particles obtained during intermedullary canal reaming (using a Reamer-Irrigator-Aspirator (RIA) device) have been evaluated as graft material during in vitro and clinical studies. The aim of this study was to evaluate and quantify new bone formation after implantation of bone graft material obtained after reaming of the tibia in a bilateral critical-sized iliac wing defect in sheep and to investigate the effect of the augmentation of this graft. A reamer bone graft alone, or after short term incubation in a dexamethasone enriched solution, and a reamer graft collected using beta-tricalcium phosphate (β-TCP) granules in the filter of the RIA collection device were compared to autologous iliac wing graft. In addition, reamer graft was combined with the cellular fraction collected from the irrigation fluid with and without short-term incubation in a dexamethasone enriched solution. It was hypothesized that the amount of physical bone in the reamer bone graft groups would be higher than the amount in the autologous iliac wing graft group and that augmentation of a reamer bone graft would increase bone formation. Three months after implantation, the amount of new bone formation (as percentage of the total defect volume) in the defects was evaluated ex-vivo by means of micro-CT and histomorphometry. The mean amount of bone in the autologous iliac wing graft group was 17.7% and 16.8% for micro-CT and histomorphometry, respectively. The mean amount of bone in all reamer graft groups ranged between 20.4-29.2% (micro-CT) and 17.0-25.4% (histomorphometry). Reamer graft collected using β-TCP granules (29.2±1.7%) in the filter produced a significantly higher amount of bone in comparison to an autologous iliac wing graft evaluated by micro-CT. RIA bone grafts added a small increase in bone volume to the 3month graft volume in this preclinical sheep model. The current model does not support the use of short-term high concentration dexamethasone for augmentation of a graft volume. If avoidance of an iliac wing graft is desirable, or a reaming procedure is required, then a RIA graft or RIA graft plus β-TCP granules are as good as the current gold standard for this model.

Qualitative and quantitative differences between bone graft obtained from the medullary canal (with a Reamer/Irrigator/Aspirator) and the iliac crest of the same patient

BACKGROUND

Donor site morbidity and limited volume remain primary drawbacks of using bone graft from the iliac crest and an impetus for finding other sources of autologous bone-graft material. The Synthes Reamer/Irrigator/Aspirator (RIA) has been found to have value as an autologous bone-graft harvesting device. The purpose of this study was to compare the cellular and biochemical characteristics of bone grafts obtained with use of the RIA and from the iliac crest of the same patient.

METHODS

A prospective study was performed on a consecutive series of ten skeletally mature patients presenting for repair of nonunited tibial or femoral fractures. Graft material was harvested from both the iliac crest (in the standard fashion) and the medullary canal of the femur or tibia (with use of the RIA) of each patient. Portions of each autologous graft sample were assessed histologically and by genomewide transcriptional profiling for biochemical markers known to be expressed during fracture-healing.

RESULTS

Principal-component analysis comparing the messenger RNA expression profiles in the RIA and iliac crest samples showed that the expression profile at each harvest site was unique and independent of patient, age, sex, or any identified comorbidity. Transcriptional analysis showed that the RIA samples had greater levels of expression of genes associated with vascular, skeletal, and hematopoietic tissues. Additionally, stem cell markers and growth factors that act early in the osteogenic cascade were more abundant in the RIA samples compared with the iliac crest samples.

CONCLUSIONS

This is the first study to directly compare the histological and molecular profiles of bone grafts from reaming debris and the iliac crest of the same patient. The debris generated during intramedullary reaming, harvested with use of the RIA technique, and the bone graft harvested from the iliac crest possessed a similar transcriptional profile for genes known to act in the early stages of bone repair and formation. This suggests that reaming debris may be a viable alternative to iliac crest bone graft when autologous cancellous graft is needed.

Harvest of cortico-cancellous intramedullary femoral bone graft using the Reamer-Irrigator-Aspirator (RIA)

The "Reamer-Irrigator-Aspirator" (RIA) is a device that provides continuous irrigation and aspiration during intramedullary reaming of long bones. The RIA system is first used to collect the reaming material from medullary cavities, a thick paste of finely morselized osseous particles containing significantly elevated levels of stem cells and growth factors as reported by quantitative analyses. The volume of bone graft material available from an adult femur corresponds to the amount of cancellous bone graft obtained from both the anterior and posterior iliac crests. The assembly and technicalities of the RIA system require a training period to prevent any femoral fracture, which appears to be the major RIA-related complication. The elective indications for RIA bone grafting are filling of bone defects in the epiphyseal and metaphyseal regions. Diaphyseal defects may also be managed using the RIA system provided the graft is placed in a constrained system (induced membrane) to prevent dispersion of the graft into the surrounding soft tissues and is aerated with a porous material to promote its revascularization. Other RIA indications include debriding intramedullary infections and reaming for intramedullary nailing of long bone fractures to reduce the risk of fat embolization.

Induced membrane technique for reconstruction to manage bone loss

Multiple surgeries are often required to manage segmental bone loss because of the complex mechanics and biology involved in reconstruction. These procedures can lead to prolonged recovery times, poor patient outcomes, and even delayed amputation. A two-stage technique uses induced biologic membranes with delayed placement of bone graft to manage this clinical challenge. In the first stage, a polymethyl methacrylate spacer is placed in the defect to produce a bioactive membrane, which appears to mature biochemically and physically 4 to 8 weeks after spacer placement. In the second, cancellous autograft is placed within this membrane and, via elution of several growth factors, the membrane appears to prevent graft resorption and promote revascularization and consolidation of new bone. Excellent clinical results have been reported, with successful reconstruction of segmental bone defects >20 cm.

Autogenous bone graft: donor sites and techniques

Autogenous cancellous bone graft provides an osteoconductive, osteoinductive, and osteogenic substrate for filling bone voids and augmenting fracture-healing.The iliac crest remains the most frequently used site for bone-graft harvest, but the proximal part of the tibia, distal end of the radius, distal aspect of the tibia, and greater trochanter are alternative donor sites that are particularly useful for bone-grafting in the ipsilateral extremity.The most common complication associated with the harvest of autogenous bone graft is pain at the donor site, with less frequent complications including nerve injury, hematoma, infection, and fracture at the donor site.Induced membranes is a method that uses a temporary polymethylmethacrylate cement spacer to create a bone-graft-friendly environment to facilitate graft incorporation, even in large segmental defects.

Staged bone grafting following placement of an antibiotic spacer block for the management of segmental long bone defects

Segmental long bone defects resulting from injury or surgical intervention are difficult problems to manage. Amputation, external fixators, vascularized fibular grafts, acute limb shortening, and various quantities of allograft and autograft have historically been the mainstays of treatment. Recently, the use of osteoinductive substances such as recombinant bone morphogenic proteins, and osteoconductive scaffolds such as calcium phosphate have found use in the treatment of these clinical situations. More recently, Masquelet described the use of a cement spacer placed within the osseous void followed by staged bone grafting within the induced biomembrane formed around the spacer as a potential treatment strategy to manage these large defects.This article describes a series of 11 patients for which we used this technique of staged bone grafting following placement of an antibiotic spacer to successfully manage osseous long bone defects ranging from 4 to 15 cm. The limbs were stabilized and aligned at the time of initial spacer placement with a plate and screw construct, intramedullary nail, or fine wire fixator. Osteoinductive substances including bone morphogenic protein-2 and platelet rich concentrate were used in addition to allograft to improve bony healing. In our series, osseous consolidation and full weight bearing was achieved in 10 of 11 patients. Two patients developed heterotopic ossification. There was 1 non-union and 1 infection, which occurred in the same patient. Staged bone grafting within an induced biomembrane created after the use of a cement spacer is a reasonable option in the management of both acute and delayed segmental long bone defects.

Complications following autologous bone graft harvesting from the iliac crest and using the RIA: a systematic review

Bone grafting is a commonly performed surgical procedure to augment bone regeneration in a variety of cases in orthopaedic and maxillofacial surgery. Autologous bone graft remains to be the 'gold standard' and the iliac crest to be the most common harvesting site. The intramedullary canal of long bones represents another potential site for large volume of autologous bone graft harvesting and is recently being used as an alternative donor site. However, harvesting of autologous bone graft is associated with morbidity and a number of complications. The aim of this systematic review was to collect and summarise the existing data on reported complications after harvesting autologous bone from the iliac crest (anterior and posterior) and the long bone intramedullary canal using the RIA device. We searched the PubMed Medline and Ovid Medline databases, from January 1990 to October 2010, to retrieve all relevant articles. A total of 92 articles (6682 patients) were included in the analysis. Overall, the complication rate following RIA was 6% (14 complications in 233 patients) and 19.37% after iliac crest bone graft harvesting (1249 complications in 6449 patients). The rate of each of the reported complications was assessed and, when the donor site was properly documented, comparison within the anterior and posterior iliac crest donor sites was performed. Although the difference of the overall morbidity rates between the two harvesting sites was not statistically significant (p=0.71); the rates of certain complications were found to significantly differ when anterior or posterior iliac crest was used. The rates of infection (p=0.016), haematoma formation (p=0.002), fracture (p=0.017), and hyperthrophic scar (p=0.017) were significantly higher when the donor site was the anterior iliac crest compared to the posterior iliac crest; whereas the rates of chronic donor site pain (p=0.004) and sensory disturbances (p=0.003) were significantly lower. The incidence of bone graft harvesting related complications can be reduced further if certain principles are followed depending on the performed harvesting methods; but overall the use of RIA device as harvesting method seems a promising alternative with a low complication rate.

Management of aseptic tibial nonunion

Tibial nonunion remains a significant clinical challenge despite advances in surgical management. New techniques to help manage tibial nonunion include extracorporeal shock wave therapy and percutaneous application of bone marrow aspirate. Management strategies vary based on the type of nonunion: aseptic or infected, and atrophic or hypertrophic. Extracorporeal shock wave therapy has been shown to be as effective as surgical management in patients with stable hypertrophic nonunion. New fixation options include locked plates and intramedullary compression nails. Novel methods of external fixation have been developed for bone graft harvest from the intramedullary canal. Several biologic adjuncts also are available, including bone marrow aspirates, stem cells, and bone morphogenetic protein.

Managing bone defects

The management of bone defects caused by trauma and nonunion continues to represent a substantial clinical challenge in the management of orthopaedic trauma patients. A variety of treatment options have been described and reported in the literature. The relative rarity of these injuries means that high level, comparative evidence to guide their management is sparse. As such, treatment decisions must be based on knowledge of the available evidence, contemporary fracture management principles, and consideration of patient and surgeon factors. This article reviews the available evidence for the different treatment options available for the management of bone defects.

Reamer-irrigator-aspirator indications and clinical results: a systematic review

BACKGROUND

The 'reamer-irrigator-aspirator' (RIA) is an innovation developed to reduce fat embolism (FE) and thermal necrosis (TN) that can occur during reaming/nailing of long-bone fractures. Since its inception its indications have expanded to include the treatment of long-bone osteomyelitis and as a harvester of bone graft/mesenchymal stem cells (MSCs).

METHODS

This study involved a systematic review, via Pubmed® and Google Scholar®, of English language sources (nine non-clinical studies, seven clinical studies and seven case reports) using the keywords: 'reamer', 'irrigator', 'aspirator' (1st May 2010). Sources were reviewed with reference to the RIAs efficacy in (1) preventing FE/TN, (2) treating long-bone osteomyelitis, (3) harvesting bone graft/MSCs, and (4) operating safely. Experimental data supports the use of the RIA in preventing FE and TN, however, there is a paucity of clinical data.

CONCLUSIONS

The RIA is a reliable method in achieving high volumes of bone graft/MSCs, and high union rates are reported when using RIA bone-fragments to treat non-unions. Evidence suggests possible effectiveness in treating long-bone osteomyelitis. The RIA appears relatively safe, with a low rate of morbidity provided a meticulous technique is used. When complications occur they respond well to conventional techniques. The RIA demands further investigation especially with respect to the optimal application of MSCs for bone repair strategies.

History and development of suction-irrigation-reaming

Excessive intramedullary pressure coincident to surgical procedures requiring entrance and surgical manipulation within the intramedullary canal is a problem that was recognized by Gerhard Küntscher, the godfather of intramedullary nailing. He expressed concern about this phenomenon in his early writings during the 1940's. Although he suggested certain technical methods to moderate the event while doing the surgical procedure he had no solution for absolutely preventing its occurrence. This became more of an issue after he introduced motorized reaming in the mid 1950's to improve the strength of intramedullary fixation. The first to demonstrate that pressure could be avoided during intramedullary surgeries were Lorenzi, Olerud and Dankwardt-Lillieström in the late 1960's. Using a method that employed suction evacuation of intramedullary content prior to reaming, and by introducing irrigation while reaming, they were able to achieve negative pressures during their intramedullary work. They proved that if an IM technique did not inject fat throughout the bone and into the organism there were significant benefits both locally and systemically. With impeccable methodology, they showed fat destroyed the vascularity of the bone and inhibited its revascularization. Systemically, its presence was associated with death and morbidity. K.M. Stürmer, using sheep in studies done in the 1980's, further validated the effectiveness of negative pressure reaming to prevent adverse effects associated with reaming. The attempt to create a device to provide these benefits clinically, however, has been challenging. The group in Muenster did work with a rinsing-suction-reamer (RSR) that showed fat introduction with reaming need not be significantly greater than when using an external fixator. In the US, the effort has focused on developing a reamer that integrated suction and irrigation into its design. This instrument has been given the acronym of RIA (reamer/irrigator/aspirator). The rationale and development of this system is detailed in this paper. Now that the intramedullary canal can be reamed using a negative pressure method this domain, as a unique source of biological material, is being increasingly investigated. The cells and tissue harvested from this space have tremendous therapeutic promise.

Reamer-irrigator-aspirator bone graft and bi Masquelet technique for segmental bone defect nonunions: a review of 25 cases

INTRODUCTION

Segmental bone loss, either from trauma, tumor or infection is a challenging clinical entity. Amputation is a possible outcome and part of the decision making process. Surgical management is almost always needed and can require several interventions to obtain bone union. A staged protocol of obtaining a clean viable soft tissue bed, placement of a PMMA antibiotic impregnated spacer to induce a neovascular and bioactive membrane followed by autogenous bone graft has been reported with good outcomes. Our study attempts to expand on this data by evaluating the use of RIA bone graft for the treatment of segmental bone loss nonunions following trauma and or infection.

METHODS

Following IRB approval, two orthopaedic trauma fellowship trained surgeons used one surgical protocol for the management of segmental bone defect nonunions. Femur RIA bone graft was used as the graft source when possible. We retrospectively evaluated patients with segmental bone loss of the lower extremity over a two year period. Our primary endpoint was clinical and radiographic bone union. A secondary endpoint was RIA related complications. Additionally, by using some known mathematical equations, we show a plausible way of quantifying the amount of bone loss from a long bone based on the shape of the bone, defect shape and the measured length of bone loss on plain radiograph.

RESULTS

25 patients with 27 segmental bone loss nonunions were evaluated. Nineteen were tibia bone loss and eight were femoral. 15 (56%) nonunions were open fractures with bone loss and 12(46%) were for bone loss related to infection or surgical debridement. The average deficit size was 5.8 cm in length (range 1-25 cm). At six months and 1 year post operative, 70% and 90% nonunions were healed clinically and radiographically respectively. There were no RIA related complications.

DISCUSSION

RIA bone graft has been shown to be a very bioactive material. Several studies support the use of this bone graft for the treatment of nonunion including one recent study evaluating 13 patients with segmental bone loss. Our study expands on this data by evaluating its use as the primary source of bone graft for the treatment of segmental bone loss nonunions in the lower extremity.

CONCLUSION

RIA bone graft for the treatment of segmental bone defect nonunion of the lower extremity appears safe and can yield predictable results when following sound surgical principles. 90% of our nonunions were healed at one year following a single bone graft procedure. Very large defects, once a formidable clinical dilemma can be managed successfully with the use of RIA bone graft.

RIA use in a community orthopedic trauma practice: applying technology, respecting biology

The RIA (Reamer Irrigator Aspirator) device is an incredibly powerful tool. It can be used to obtain biologically active tissue for healing at local or distant sites. Additionally, it can be used to lower the negative bioburden of disease and even to assist in diagnosis. As with any powerful tool, it should be used with detailed pre-planning and great respect. Once properly understood and implemented, the device can be used in many ways:

Treatment of long bone intramedullary infection using the RIA for removal of infected tissue: indications, method and clinical results

Treatment of intramedullary infections of long bones is based upon the principles of surgical debridement, irrigation, fracture site stabilization, soft tissue coverage, and antibiotic administration. Reaming of the medullary canal is an essential component of surgical debridement because it removes intramedullary debris and infected bone surrounding the removed intramedullary device and within the intramedullary canal. The Reamer-Irrigator-Aspirator (RIA) has distinct features that appear to be beneficial for management of intramedullary infections. It allows reaming under simultaneous irrigation and aspiration, which minimizes the residual amount of infected fluid and tissue in the medullary canal and the propagation of infected material. The disposable reamer head is sharp, which combined with the continuous irrigation may attenuate the increased temperature associated with reaming and its potential adverse effects on adjacent endosteal bone. The disadvantage of the RIA is increased cost because of use of disposable parts. Potential complications can be avoided by detailed preoperative planning and careful surgical technique. The RIA should be used with caution in patients with narrow medullary canals and in infections involving the metaphysis or a limited part of the medullary canal. Reaming of the canal is performed with one pass of the RIA under careful fluoroscopic control. Limited information is available in the literature on the results of the RIA for management of intramedullary infections of long bones; however preliminary results are promising. The RIA device appears to be an effective and safe tool for debridement of the medullary canal and management of intramedullary infections of the long bones. Further research is needed to clarify the exact contribution of the RIA in the management of these infections.