Cortical heat generation using an irrigating/aspirating single-pass reaming vs conventional stepwise reaming

In vivo study to assess fat embolism resulting from the Reamer-Irrigator-Aspirator 2 system compared to a novel aspirator-based concept for intramedullary bone graft harvesting

INTRODUCTION

Fat embolism (FE) following intramedullary (IM) reaming can cause severe pulmonary complications and sudden death. Recently, a new harvesting concept was introduced in which a novel aspirator is used first for bone marrow (BM) aspiration and then for subsequent aspiration of morselized endosteal bone during sequential reaming (A + R + A). In contrast to the established Reamer-Irrigator-Aspirator (RIA) 2 system, the new A + R + A concept allows for the evacuation of fatty BM prior to reaming. In this study, we hypothesized that the risk of FE, associated coagulopathic reactions and pulmonary FE would be comparable between the RIA 2 system and the A + R + A concept.

MATERIALS AND METHODS

Intramedullary bone graft was harvested from intact femora of 16 Merino sheep (age: 1-2 years) with either the RIA 2 system (n = 8) or the A + R + A concept (n = 8). Fat intravasation was monitored with the Gurd test, coagulopathic response with D-dimer blood level concentration and pulmonary FE with histological evaluation of the lungs.

RESULTS

The total number and average size of intravasated fat particles was similar between groups (p = 0.13 and p = 0.98, respectively). D-dimer concentration did not significantly increase within 4 h after completion of surgery (RIA 2: p = 0.82; A + R + A: p = 0.23), with an interaction effect similar between groups (p = 0.65). The average lung area covered with fat globules was similar between groups (p = 0.17).

CONCLUSIONS

The use of the RIA 2 system and the novel A + R + A harvesting concept which consists of BM evacuation followed by sequential IM reaming and aspiration of endosteal bone, resulted in only minor fat intravasation, coagulopathic reactions and pulmonary FE, with no significant differences between the groups. Our results, therefore, suggest that both the RIA 2 system and the new A + R + A concept are comparable technologies in terms of FE-related complications.

An in vivo study to investigate an original intramedullary bone graft harvesting technology

BACKGROUND

Harvesting bone graft (BG) from the intramedullary canal to treat bone defects is largely conducted using the Reamer-Irrigator-Aspirator (RIA) system. The RIA system uses irrigation fluid during harvesting, which may result in washout of osteoinductive factors. Here, we propose a new harvesting technology dedicated to improving BG collection without the potential washout effect of osteoinductive factors associated with irrigation fluid. This novel technology involves the conceptual approach of first aspirating the bone marrow (BM) with a novel aspirator prototype, followed by reaming with standard reamers and collecting the bone chips with the aspirator (reaming-aspiration method, R-A method). The aim of this study was to assess the harvesting efficacy and osteoinductive profile of the BG harvested with RIA 2 system (RIA 2 group) compared to the novel harvesting concept (aspirator + R-A method, ARA group).

METHODS

Pre-planning computed tomography (CT) imaging was conducted on 16 sheep to determine the femoral isthmus canal diameter. In this non-recovery study, sheep were divided into two groups: RIA 2 group (n = 8) and ARA group (n = 8). We measured BG weight collected from left femur and determined femoral cortical bone volume reduction in postoperative CT imaging. Growth factor and inflammatory cytokine amounts of the BGs were quantified using enzyme-linked immunosorbent assay (ELISA) methods.

RESULTS

The use of the stand-alone novel aspirator in BM collection, and in harvesting BG when the aspirator is used in conjunction with sequential reaming (R-A method) was proven feasible. ELISA results showed that the collected BG contained relevant amounts of growth factors and inflammatory cytokines in both the RIA 2 and the ARA group.

CONCLUSIONS

Here, we present the first results of an innovative concept for harvesting intramedullary BG. It is a prototype of a novel aspirator technology that enables the stepwise harvesting of first BM and subsequent bone chips from the intramedullary canal of long bones. Both the BG collected with the RIA 2 system and the aspirator prototype had the capacity to preserve the BG's osteoinductive microenvironment. Future in vivo studies are required to confirm the bone regenerative capacity of BG harvested with the innovative harvesting technology.

Low-Intensity Pulsed Ultrasound Promotes Osteogenic Differentiation of Reamer-Irrigator-Aspirator Graft-Derived Cells in Vitro

Recently, reamer-irrigator-aspirator (RIA) systems have been increasingly used to harvest autologous bone grafts. RIA graft materials contain bone marrow, which provides a viable source to derive large numbers of mesenchymal stem cells. Low-intensity pulsed ultrasound (LIPUS) significantly accelerates the differentiation of stem cells derived from bone marrow. This in vitro study investigated the effect of LIPUS on the osteogenic activity and differentiation of RIA graft-derived cells. A small amount of RIA graft was obtained from seven patients. After the cells derived from RIA grafts were cultured, they were divided into two groups: the LIPUS and control groups. LIPUS was applied once daily for 20 min (1.5 MHz, pulse duration: 200 µs, pulse repetition rate: 1 kHz, spatial average-temporal average intensity: 30 mW/cm²). Alkaline phosphatase activity (113.4% and 130.1% on days 7 and 14), expression of osteoblast-related genes (ALP, Runx2) and mineralization (135.2% on day 21) of the RIA graft-derived cells were significantly higher in the LIPUS group than in the control group. However, LIPUS did not affect the cell proliferation of RIA graft-derived cells. This study indicates that LIPUS may enhance the healing of non-union and critical bone defects treated by autologous bone grafting using the RIA system.

Clinical experience of the use of reamer irrigator aspirator in Japanese patients: A report of the first 42 cases

BACKGROUND

A reamer irrigator aspirator (RIA) can be used to harvest substantial amounts of autologous bone and debride the intramedullary canal. Clinical experience using reamer irrigator aspirators in Japan is very limited. The applicability of the reamer irrigator aspirator head with a minimum diameter of 12 mm for Japanese people is often questioned as the Japanese are smaller than Americans and Europeans. There are no reports of complications in Japanese patients. This study aimed to retrospectively review clinical cases and describe reamer irrigator aspirator use in Japanese patients.

METHODS

All patients for whom a reamer irrigator aspirator was used during surgery at our hospital between January 2014 and September 2018 were included. The patients' clinical and radiographic data were retrospectively reviewed.

RESULTS

Data of 40 patients (42 cases) were collected. The reamer irrigator aspirator was used for bone graft harvesting in 32 cases, intramedullary debridement and irrigation in 9 cases, and reaming for exchange nailing in 1 case. The diameter of the reamer irrigator aspirator reamer head was 12 mm in 22 cases (53.7%), 12.5 mm in 4 cases (9.8%), 13 mm in 9 cases (22.0%), 13.5 mm in 1 case (2.4%), 14.0 mm in 1 case (2.4%), 14.5 mm in 1 case (2.4%), and 15 mm in 4 cases (9.8%). Mean intraoperative bleeding volume was 1158.6 mL (range, 100-3800 mL). We experienced no difficulty inserting the reamer irrigator aspirator into the intramedullary canals and no cases of insertion-related intraoperative fracture. Five cortical perforations (11.9%) were observed on postoperative computed tomography scans, although no patient was symptomatic. One case (2.4%) of postoperative femur fracture occurred.

CONCLUSIONS

Reamer irrigator aspirators can be used in Japanese patients. Smaller reamer head sizes were mainly used in our experience. We should manage complications as in previous reports from Western countries.

Intramedullary tissue cultures from the Reamer-Irrigator-Aspirator system for diagnosing fracture-related infection

Fracture-related infection (FRI) is a serious complication following musculoskeletal trauma. Accurate diagnosis and appropriate treatment depend on retrieving adequate deep tissue biopsies for bacterial culture. The aim of this cohort study was to compare intraoperative tissue cultures obtained by the Reamer-Irrigator-Aspirator system (RIA)-system against standard tissue cultures obtained during the same surgical procedure. All patients had long bone fractures of the lower limbs and were assigned to the FRI or Control group based on the FRI consensus definition. The FRI group consisted of 24 patients with confirmed FRI and the Control group consisted of 21 patients with aseptic nonunion or chronic pain (in the absence of other suggestive/confirmatory criteria). Standard tissue cultures and cultures harvested by the RIA-system showed similar results. In the FRI group, standard tissue cultures and RIA cultures revealed relevant pathogens in 67% and 71% of patients, respectively. Furthermore, in four FRI patients, cultures obtained by the RIA-system revealed additional relevant pathogens that were not found by standard tissue culturing, which contributed to the optimization of the treatment plan. In the Control group, there were no false-positive RIA culture results. As a proof-of-concept, this cohort study showed that the RIA-system could have a role in the diagnosis of FRI as an adjunct to standard tissue cultures. Since scientific evidence on the added value of the RIA-system in the management of FRI is currently limited, further research on this topic is required before its routine application in clinical practice.

Protective effects of new femoral reaming techniques (Reamer irrigator aspirator, RIA I and II) on pulmonary function and posttraumatic contusion (CT morphology) - results from a standardized large animal model

INTRODUCTION

The effects of reaming for preparation of intramedullary fixation in long bone fractures have been widely studied. We compared pulmonary and systemic effects between conventional reaming with reamer irrigator aspirator and unreamed nailing in an acute porcine trauma model with a standardized femur fracture.

MATERIALS AND METHODS

In a standardized porcine model, (moderate blunt chest trauma, abdominal injury and femoral shaft fracture), the femur was submitted to intramedullary nailing after resuscitation and normalization of pulmonary function. The treatment groups included 3 reamer types (Group RFN: conventional reaming with Synream; group RIA1; reamer irrigator aspirator, version 2005; group RIA 2; reamer irrigator aspirator, version 2019) and were compared to unreamed femoral nailing (Group UFN). Pulmonary function measurements included arterial partial carbon-dioxide pressure (paCO₂ [kPa]) (baseline, post reaming, 2,4,6 h) and volumetric measures of contusion in chest computer tomography (CT) (at 6 hrs.). Systemic inflammatory response was measured at baseline and every second hour until six hours after trauma.

RESULTS

This study included 24 male animals, mean weight 50.76 ± 4.1 kg n = 6 per group). Group RFN developed a significantly higher partial CO₂ (pCO₂) at one hour after reaming when compared with all other groups (7.4 ± 0.4 kPa versus 5.4 ± 0.6 RIA 1, 5.6 ± 0.4 RIA 2, and 5.5 ± 0.5 UFN, p < 0.001), along with a had lower pO₂ (12.3 ± 1.3 kPa versus 17.2 ± 1.9 RIA 1, 17.4 ± 1.6 RIA 2, and 16.4 ± 0.7 UFN, p < 0.001) and the degree of pulmonary hyperdense changes in the CT analysis was higher in RFN (485.2 ± 98.5 cm³ versus 344.4 ± 74.4 cm³ RIA 1 and 335.2 ± 58.1 cm³ RIA 2, p < 0.01). The inflammatory reaction was lowest in both RIA groups when compared with group RFN or UFN (p < 0.001).

CONCLUSION

Both RIA 1 and RIA 2 protect the lung from reaming induced dysfunction and have no systemic inflammatory effects, while the negative effects were more sustained after reamed or unreamed nailing. Both RIA 1 and RIA II appear to be of value in terms of a Safe Definitive Surgery (SDS) strategy.

Intramedullary reaming modality for management of postoperative long bone infection: a prospective randomized controlled trial in 44 patients

Background

Studies addressing the management of intramedullary infection are mainly retrospective and with a limited number of cases. Reaming can be performed using either conventional reaming or using the reamer/irrigator/aspirator (RIA) system. Until now there have been no comparative prospective studies between these two methods. We aimed to compare the efficacy of RIA with conventional reaming followed by insertion of antibiotic-loaded cement, for the treatment of intramedullary nail infection of long bones. We assessed the rate of remission between groups after two-year follow-up and identified microorganisms using tissue cultures and sonication of explanted intramedullary nail (IMN).

Methods

A noninferiority, randomized clinical trial was carried out between August 2013 and August 2015 involving 44 patients of whom a locked IMN implant of the femur and/or tibia was retrieved and who all met the clinical and radiological criteria for IMN-associated osteomyelitis. Patients were randomized into two groups: RIA alone versus conventional reaming followed by antibiotic-loaded cement insertion. Both groups also underwent six-weeks of antibiotic treatment according to the results of the antibiogram. Patients were evaluated after 1, 3, 6, 12 and 24 months for radiological and clinical follow-up.

Results

After 24 months, the rate of infection remission was similar between the two groups, 87% in the RIA group and 95.5% in the conventional reaming group (p = 0.60). Among four patients who had recurrence of infection, the time to reappearance of symptoms varied from 20 days to twenty-two months. Staphylococcus aureus and coagulase-negative Staphylococci were isolated in 23 (40.4%) and 13 (22.9%) patients, respectively. Interestingly, we identified 20% (9/45) of polymicrobial infection.

Conclusion

This study concludes that the RIA system alone, is noninferior to conventional reaming followed by antibiotic cement spacer in the treatment of IMN infection. However, RIA shows greater efficacy in the collection of infected medullary bone tissue, mainly in cases of infected retrograde nail of the femur.

Trial registration

ISRCTN82233198. Retroactively registered on July 29, 2019.

The Reamer-Irrigator-Aspirator technique for manubriosternal non-union repair†

Autologous bone graft is used in the treatment of fracture non-unions. A novel approach to treat painful manubriosternal non-unions is described with bone graft harvested from the femur and plating.

Autograft, Allograft, and Bone Graft Substitutes: Clinical Evidence and Indications for Use in the Setting of Orthopaedic Trauma Surgery

Bone grafts are the second most common tissue transplanted in the United States, and they are an essential treatment tool in the field of acute and reconstructive traumatic orthopaedic surgery. Available in cancellous, cortical, or bone marrow aspirate form, autogenous bone graft is regarded as the gold standard in the treatment of posttraumatic conditions such as fracture, delayed union, and nonunion. However, drawbacks including donor-site morbidity and limited quantity of graft available for harvest make autograft a less-than-ideal option for certain patient populations. Advancements in allograft and bone graft substitutes in the past decade have created viable alternatives that circumvent some of the weak points of autografts. Allograft is a favorable alternative for its convenience, abundance, and lack of procurement-related patient morbidity. Options include structural, particulate, and demineralized bone matrix form. Commonly used bone graft substitutes include calcium phosphate and calcium sulfate synthetics-these grafts provide their own benefits in structural support and availability. In addition, different growth factors including bone morphogenic proteins can augment the healing process of bony defects treated with grafts. Autograft, allograft, and bone graft substitutes all possess their own varying degrees of osteogenic, osteoconductive, and osteoinductive properties that make them better suited for different procedures. It is the purpose of this review to characterize these properties and present clinical evidence supporting their indications for use in the hopes of better elucidating treatment options for patients requiring bone grafting in an orthopaedic trauma setting.

Assessment of Reamer Irrigator Aspirator System (RIA) filtrate for its osteoinductive potential in a validated animal model

PURPOSE

Previous studies indicate that Reamer Irrigator Aspirator (RIA) filtrate contains proteins that have the potential to stimulate bone healing. This study aimed to determine the osteoinductive capabilities of RIA filtrate in a validated in vivo model.

METHODS

With Institutional Review Board approval, RIA filtrates from 9 patients were collected. The filtrate was processed to remove cells and inorganic particles. A portion of each sample was set aside for protein analysis while the remainder was lyophilized and prepared for implantation. With Animal Care and Use Committee approval, athymic mice (n = 16; 32 hind limbs) were randomly assigned to 1 of 4 groups (n = 8 limbs per group) for percutaneous gastrocnemius muscle injection of demineralized bone matrix (DBM) (10 mg), lyophilized RIA powder (10 mg), RIA liquid (10 mg of lyophilized RIA powder in 100ul phosphate buffered saline (PBS)), or DBM (10 mg) + RIA liquid (10 mg in 100ul PBS). Radiographs were obtained 2, 4, and 8 weeks after injection. At 8 weeks, mice were sacrificed and the entire gastrocnemius muscle from each hind limb was collected and processed for histologic examination. Histological sections and radiographs were assessed for ossification/calcification. Data were compared for statistically significant (p < 0.05) differences among groups and strong (R > 0.7) correlations between outcome measures.

RESULTS

The protein composition of RIA filtrates was consistent among patients and matched previous data. For all groups, radiographic scores were significantly (p < 0.014) higher (more calcification/ossification) at 8 weeks compared to 2 weeks. Radiographic scores for the DBM and DBM + RIA liquid groups were significantly higher than RIA liquid and RIA powder at 4 weeks and 8 weeks (p < 0.019 and p < 0.049, respectively). Histologic scores were significantly (p = 0.004) higher in the DBM + RIA liquid group compared to the RIA liquid group at 8 weeks. Histologic scores showed strong correlations (r > 0.77) to radiographic scores for all groups.

CONCLUSION

RIA filtrate liquid and powder were osteoinductive in vivo with new bone formation being most abundant using a combination of DBM and RIA filtrate in this validated animal model. RIA filtrate has potential for clinical use in augmenting bone healing treatments.

Complications and risk management in the use of the reaming-irrigator-aspirator (RIA) system: RIA is a safe and reliable method in harvesting autologous bone graft

BACKGROUND

Autologous bone grafting (ABG) remains the gold standard for augmentation of bone defects. The RIA system has become more prevalent, but evidence regarding risk management and complications remain scarce. This study presents the risk management and complications associated with RIA in the largest single-center case series to date.

METHODS

All records, operative notes, lab data and radiographs of patients receiving a RIA procedure at Heidelberg´s University Hospital between 01/01/2010 and 31/12/2016 were reviewed. Multivariate logistic regression models adjusting for clinically relevant covariates were used to examine the respective relevance regarding the presence and absence of prolonged postoperative pain (PPP).

RESULTS

A total of 341 RIA procedures on 306 patients were performed at our level-1 trauma center. The femur was the main donor site (98.53%; N = 336) whereas only in 1.47% (N = 5) the tibia was utilized. A total of 11 patients showed a relevant loss of hemoglobin requiring blood transfusion. A total of 22 patients suffered from PPP directly associated with the RIA procedure resulting in prevalence of 6.45%. The 6 major complications in our study were of diverse origin and all intraoperative complications took place in the early phase of the RIA procedure in our center (2010-2013). Our data revealed influence of sex (p = 0.0459) and age (p = 0.0596) on the criterion PPP. The favored model including sex and age resulted in an AUC of 66.2% (CI: 55.5%-76.9%).

CONCLUSION

Perioperative blood loss remains a prevalent complication during RIA reaming. In addition, PPP occurs with a prevalence of 6.45%. This study showed a complication rate of 1.76%, emphasizing RIA´s overall safety and furthermore highlighting the need for vigilance in its application and prior extensive hands-on training of surgeons. Level of Evidence: II.

Treatment of critical-sized bone defects: clinical and tissue engineering perspectives

Critical-sized bone defects are defined as those that will not heal spontaneously within a patient's lifetime. Current treatment options include vascularized bone grafts, distraction osteogenesis, and the induced membrane technique. The induced membrane technique is an increasingly utilized method with favorable results including high rates of union. Tissue engineering holds promise in the treatment of large bone defects due to advancement of stem cell biology, novel biomaterials, and 3D bioprinting. In this review, we provide an overview of the current operative treatment strategies of critical-sized bone defects as well as the current state of tissue engineering for such defects.

Salvage of an osteocutaneous thermonecrosis secondary to tibial reaming by the induced membrane procedure

Osteocutaneous thermonecrosis is a rare but devastating complication of tibial reaming, which can cause large and infected bone and cutaneous defects. The case presented here illustrates that the induced membrane technique described by Masquelet is a valuable option in treating this complication.

Inflammatory response after nailing

Intramedullary nailing, as the gold standard stabilisation method of most long bones, has been tailed by its extensive use as the basic tool of investigating the immune response to trauma in many large and small animal models, as well as at the clinical setting. Over the last few decades a complex map of interactions between pro and anti-inflammatory pathways has been the result of these significant global research efforts. Parallel to the evolution of modern nailing and reaming techniques, significant developments at the fields of other disciplines relevant to trauma care, has improved the contemporary management of injured patients, challenging previous concepts and altering clinical barriers. The current article aims to summarise the current understanding of the effect of instrumenting the medullary canal after trauma, and hint on potential future directions.

Extended applications of the reamer-irrigator-aspirator (RIA) system

While the RIA system was initially designed for reaming and clearing the femoral canal contents in preparation for femoral nailing, it has since been used in various other applications in the field of orthopaedic surgery. The RIA is an ideal device for accessing large quantities of autogenous bone graft, to be used in the treatment of nonunions, segmental bone loss, or arthrodesis. The RIA has also been used for treatment of intramedullary infections and osteomyelitis, as well as intramedullary nailing of long bones with metastatic lesions, as it allows for clearing the canal of infectious/tumour burden, and lowers the risk of dissemination into the soft tissues and systemic circulation. There is also some limited evidence that the RIA may be used for clearing the femoral/tibial canal of cement debris. Despite multiple applications, the use of RIA has a risk of eccentric reaming and iatrogenic fractures. RIA is also a costly procedure, and its routine use may not be advantageous in the setting of limited health care resources.

Bone grafting via reamer-irrigator-aspirator for nonunion of open Gustilo-Anderson type III tibial fractures treated with multiplanar external fixator

Introduction: The purpose of this investigation was to evaluate the outcomes following reamer-irrigator-aspirator (RIA) autogenous bone grafting (ABG) of high-grade open tibia fracture nonunions stabilized via multiplanar external fixation.

Methods: We retrospectively reviewed all patients with Gustilo-Anderson type III open tibia fractures treated with multiplanar external fixation and who underwent RIA ABG for nonunion at our institutional Level 1 Trauma Center between 2008 and 2015. All patients between 15 and 65 years of age with a minimum of six-month follow-up were included. The primary outcomes of interest were achievement of union, time to union, and incidence of revision surgery. Complications and all-cause reoperation were recorded as secondary endpoints.

Results: Fifteen patients met the inclusion criteria with a mean age of 41.1 ± 14.0 years. RIA ABG was harvested from the femur in all cases, with a mean volume of 34 ± 15 mL. At an average follow-up of 13.3 ± 6.8 months, all patients achieved union, including two who required repeat RIA ABG. One patient experienced a femoral shaft fracture four months following RIA that required intramedullary fixation. The average time to union was 6.0 ± 6.3 months. Twelve patients (80%) went on to union within six months and 13 (86.7%) within one year. Five patients experienced a total of six post-operative complications including three deep infections, one refracture through the nonunion site, and one gradual varus deformity. Two patients in this series required a subsequent RIA autografting procedure secondary to persistent nonunion despite initial RIA.

Conclusion: We found that RIA ABG offered a reliable solution to nonunion of Gustilo-Anderson type III open tibial fractures treated with multiplanar external fixation, circumventing the need to change the method of fixation.

Prospective Randomized Clinical Trial Investigating the Effect of the Reamer-Irrigator-Aspirator on the Volume of Embolic Load and Respiratory Function During Intramedullary Nailing of Femoral Shaft Fractures

OBJECTIVES

We sought to determine whether the use of the Reamer-Irrigator-Aspirator (RIA) device resulted in a decreased amount of fat emboli compared with standard reaming (SR) when performing intramedullary (IM) nailing of femoral shaft fractures.

DESIGN

Prospective randomized clinical trial.

SETTING

Multi-centered trial, level I trauma centers.

PATIENTS/PARTICIPANTS

All eligible patients who presented to participating institutions with an isolated femoral shaft fracture amenable to fixation with antegrade IM nailing. Thirty-one patients were enrolled: nine were excluded because of technical difficulties with the transesophageal echocardiogram (TEE) recording. Therefore, the study comprised 22 patients: 11 patients randomized to the SR group and eleven patients randomized to the RIA group.

INTERVENTION

Antegrade IM nailing of a femoral shaft fracture with standard reamers or the RIA device. All patients were monitored intraoperatively with a continuous TEE to assess embolic events in the right atrium. A radial arterial line was used to monitor blood gases and potential systemic effects of emboli.

MAIN OUTCOME MEASURE

Duration, size, and severity of emboli as measured by TEE. The operative procedure was divided into 6 distinct stages: preoperative, reduction, guidewire passage, reaming, nail insertion, and postoperative.

RESULTS

There was no significant difference in emboli between the RIA and SR groups preoperatively, during fracture reduction, guidewire insertion, or postoperatively. Measured with a standardized scoring system, there was a modest reduction in total emboli score in the RIA group during reaming (SR 5.30 [SD; 1.81] vs. RIA 4.05 [SD; 2.19], P = 0.005) and during nail insertion (SR 5.09 [SD; 1.74] vs. RIA 4.25 [SD; 1.89], P = 0.03). We were unable to correlate this reduction with any improvement in physiologic parameters (mean arterial pressure, end-tidal CO2, O2 saturation, pH, paO2, and paCO2).

CONCLUSIONS

This study showed a modest reduction of embolic debris during the reaming and nail insertion segments of the operative procedure. We were unable to correlate this with any change in physiologic parameters.

LEVEL OF EVIDENCE

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

Use of the Reamer/Irrigator/Aspirator Decreases Carotid and Cranial Embolic Events in a Canine Model

BACKGROUND

Approximately 2 million patients in the United States annually undergo total joint arthroplasty with reaming and placement of intramedullary nails, resulting in extravasation of bone marrow and fat into the circulatory system and potentially causing fat embolism syndrome. Acute and chronic changes in mental status documented after these procedures may be related to embolic events. The Reamer/Irrigator/Aspirator (RIA) device has been shown to decrease intramedullary pressure during reaming. We hypothesized that the use of the RIA in a canine model would reduce the number of microemboli detected in the carotid artery and brain compared with nailing either with or without reaming.

METHODS

Twenty-four large canines underwent unreamed nailing (UR), sequentially reamed nailing (SR), or RIA-reamed nailing (RIA) of bilateral femora (eight dogs per group). During reaming and nailing, the number and size of microemboli transiting the carotid artery were recorded. After euthanasia, the brain was harvested for immunostaining and measurement of microinfarction volumes.

RESULTS

Total embolic load passing through the carotid artery was 0.049 cc (UR), 0.045 cc (SR), and 0.013 cc (RIA). The number and size of microemboli in the UR and SR groups were similar; however, the RIA group had significantly fewer larger-sized (>200-μm) emboli (p = 0.03). Pathologic examination of the brain confirmed particulate emboli, and histologic analyses demonstrated upregulation of stress-related proteins in all groups, with fewer emboli and less evidence of stress for RIA reaming.

CONCLUSIONS

RIA reaming decreased microemboli compared with traditional reaming and unreamed nailing, suggesting that intramedullary pressure and heat are important variables. The documented embolic events and brain stress may help to explain subtle neurobehavioral symptoms commonly seen in patients after undergoing long-bone reaming procedures.

CLINICAL RELEVANCE

RIA reaming decreased cranial embolic events and may have an ameliorating effect on postoperative neurologic sequelae.

Trephine Use During Revision Total Hip Arthroplasty Resulting in Diaphyseal Osteonecrosis and Stress Fracture: A Case Report

CASE

A fifty-three-year-old woman presented with a fracture of an extensively porous-coated femoral component. Revision was performed with use of trephine reamers to remove the distal portion of the stem. Despite radiographs that showed an acceptable position of the revision stem, she experienced substantial thigh pain at four months postoperatively, which persisted at twelve months. A technetium-99m bone scan demonstrated a 5-cm photopenic region, suggestive of thermal osteonecrosis. Two months later, there was evidence of callus formation, which is consistent with a stress fracture. The fracture was treated with protected weight-bearing; it healed with nonoperative management and resolution of the pain.

CONCLUSION

A diaphyseal stress fracture secondary to thermal osteonecrosis associated with trephine use developed after removal of a broken femoral component; it healed without surgical intervention.

Management of infected non-union of the proximal femur: a combination of therapeutic techniques

A challenging case of a nonunion of the proximal femur complicated by infection attributed to microbial and fungal pathogens requiring a combination of novel surgical techniques to achieve eradication of infection, preservation of the native hip joint, and restoration of function.

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.

Subaquatic reaming during arthrodesis of the first metatarsophalangeal joint to prevent thermal necrosis of bone

When performing fusions of the first metatarsophalangeal joint, it has been hypothesized that the use of a cup and cone reamer may cause thermal necrosis, leading to potential nonunion. The friction created by the reamer spinning against the bone has been shown to cause elevations of temperatures capable of causing thermal necrosis. Failing to cool the bony-reamer interface, or doing so inadequately with a bulb syringe, increases the patient's odds of experiencing a nonunion. The authors describe a simple technique that prevents significant temperature elevations at the reamer-bony interface, decreasing the potential for thermal necrosis and increasing the likelihood of successful fusion. The authors have performed this procedure for several patients without complications.

Lateral drill holes decrease strength of the femur: an observational study using finite element and experimental analyses

Background

Internal fixation of femoral fractures requires drilling holes through the cortical bone of the shaft of the femur. Intramedullary suction reduces the fat emboli produced by reaming and nailing femoral fractures but requires four suction portals to be drilled into the femoral shaft. This work investigated the effect of these additional holes on the strength of the femur.

Methods

Finite element analysis (FEA) was used to calculate compression, tension and load limits which were then compared to the results from mechanical testing. Models of intact femora and fractured femora internally fixed with intramedullary nailing were generated. In addition, four suction portals, lateral, anterior and posterior, were modelled. Stresses were used to calculate safety factors and predict fatigue. Physical testing on synthetic femora was carried out on a universal mechanical testing machine.

Results

The FEA model for stresses generated during walking showed tensile stresses in the lateral femur and compression stresses in the medial femur with a maximum sheer stress through the neck of the femur. The lateral suction portals produced tensile stresses up to over 300% greater than in the femur without suction portals. The anterior and posterior portals did not significantly increase stresses. The lateral suction portals had a safety factor of 0.7, while the anterior and posterior posts had safety factors of 2.4 times walking loads. Synthetic bone subjected to cyclical loading and load to failure showed similar results. On mechanical testing, all constructs failed at the neck of the femur.

Conclusions

The anterior suction portals produced minimal increases in stress to loading so are the preferred site should a femur require such drill holes for suction or internal fixation.

Changes in femoral cortical porosity after reaming and intramedullary canal preparation in a canine model

This study examined changes in femoral cortical porosity resulting from femoral canal preparation during cemented total hip arthroplasty (THA). Twenty-four canines were randomly assigned to 3 groups: (1) reaming only, (2) cementing without pressurization, and (3) cementing with pressurization. Femoral cortical porosity was measured from histologic samples of the femurs at 7 positions. Reaming during canal preparation significantly increased cortical porosity. Cementing further increased cortical porosity, whereas pressurization of cement helped to counteract the increase in cortical porosity caused by cementing alone. Cortical porosity was considered to be a marker for bone mineral density (BMD) during the early phase of peri-implant healing around cemented stems. To maximize bone mineral density after cemented total hip arthroplasty, we suggest using implants that do not require reaming and pressurizing cement appropriately.

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.

Polytrauma – new horizons for management

The management of polytrauma has evolved considerably in the last century. Advances have been made in all disciplines involved in trauma care from pre-hospital care and resuscitation protocols to diagnostics, surgical techniques, administration of novel pharmacological agents and late reconstruction procedures. Improved understanding of the altered physiology and the induced response at the molecular level offers the potential for novel management strategies and prevention of post-traumatic complications.

Use of the reamer–irrigator–aspirator technique to obtain autograft for ankle and hindfoot arthrodesis

The use of autograft bone is the best option when undertaking a procedure that requires bone graft because it is osteogenic, osteoconductive and osseo-inductive. Pain, morbidity and complications associated with harvesting iliac or non-iliac sites occur in between 6% and 30% of cases. An alternative source of graft with possibly a lower morbidity is the intramedullary canal. In this study, 28 patients undergoing 30 arthrodesis procedures on the hindfoot had a mean of 48 cm3 (43 to 50) of bone harvested locally from the hindfoot or the tibial shaft by antegrade or retrograde reaming. No patient sustained a fracture of the calcaneum, talus or tibia. There was no morbidity except for one complication when the reamer breached the medial tibial cortex. This healed uneventfully.

This method of using the reamer–irrigator–aspirator system is an extension of the standard technique of intramedullary reaming of the lower limb: it produces good-quality bone graft with viable growth factors consistent with that of the iliac crest, and donor site morbidity is low. This is an efficient method of obtaining autologous bone for use in arthrodesis of the ankle or hindfoot.

Novel venting technique for intramedullary rod fixation of pathologic fractures

This article introduces a novel technique to vent the femur and potentially decrease the embolic load created by reaming during intramedullary rod fixation of impending pathologic femur fractures. We used readily available operating room equipment to create a distal femoral vent hole without interfering with standard intramedullary instrumentation and with minimal increase in surgical time. This technique can be used for the prophylactic intramedullary stabilization of impending pathologic femur fractures from metabolic bone disease, metastatic cancer, and bisphosphonate use.

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.

Reaming Irrigator Aspirator system: early experience of its multipurpose use

The evolution of contemporary intramedullary reaming systems has recently generated the Reamer Irrigator Aspirator system (RIA-Synthes®), which has progressively gained in popularity as well as in indications. The preliminary results of its use over the initial period of 18 months ata single tertiary referral centre were prospectively collected and are presented. The wide spectrum of RIA's indications have been exploited, including 7 patients with polytrauma that underwent acute femoral nailing, 8 with femoral intramedullary osteomyelitis, 9 with pathological lesions of the femoral shaft, as well as 18 patients where the RIA system has been used to harvest morselised autologous bone graft in the presence of recalcitrant atrophie non-unions and bone defects. Overall its use was proven safe and efficient, achieving aggressive medullary canal debridement, collection of adequate samples for further analysis in the infected and oncology cases, as well as impressive volumes of the osteoinductive and osteogenic reaming debris for grafting purposes. No pulmonary complications or evidence of the second hit sequelae were recorded in the polytrauma patient subgroup despite the presence of a high ISS Further controlled clinical studies should follow focused in all different applications of this reliable, user-friendly and impressively versatile system, to validate these preliminary results.

The use of the reamer-irrigator-aspirator to harvest mesenchymal stem cells

The scarcity of mesenchymal stem cells (MSCs) in iliac crest bone marrow aspirate (ICBMA), and the expense and time in culturing cells, has led to the search for alternative harvest sites. The reamer-irrigation-aspirator (RIA) provides continuous irrigation and suction during reaming of long bones. The aspirated contents pass via a filter, trapping bony fragments, before moving into a 'waste' bag from which MSCs have been previously isolated. We examined the liquid and solid phases, performed a novel digestion of the solid phase, and made a comparative assessment in terms of number, phenotype and differentiation capacity with matched ICBMA. The solid fraction from the filtrate was digested for 60 minutes at 37° C with collagenase. Enumeration was performed via the colony-forming unit fibroblast (CFU-F) assay. Passage (P2) cells were differentiated towards osteogenic, adipogenic and chondrogenic lineages, and their phenotypes assessed using flow cytometry (CD33, CD34, CD45, CD73, CD90, and CD105). MSCs from the RIA phases were able to differentiate at least as well as those from ICBMA, and all fractions had phenotypes consistent with other established sources. The median number of colonies for the three groups was: ICBMA = 8.5 (2 to 86), RIA-liquid = 19.5 (4 to 90), RIA-solid = 109 (67 to 200) per 200 μl. The mean total yield of cells for the three groups was: ICBMA = 920 (0 to 4275), RIA-liquid = 114,983 (16,500 to 477,750), RIA-solid = 12,785 (7210 to 28 475). The RIA filtrate contains large numbers of MSCs that could potentially be extracted without enzymatic digestion and used for bone repair without prior cell expansion.

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.

Unreamed or RIA reamed nailing: an experimental sheep study using comparative histological assessment of affected bone tissue in an acute fracture model

The purpose of the present study was to evaluate the Reamer/Irrigator/Aspirator (RIA), a reaming system designed to incorporate the advantages of irrigation and suction for every day clinical use. The evaluation process was focused on the displacement of the medullary content and its impact on cortical perfusion. The results of the RIA reamed nailing were compared to conventional non-reamed nailing (NRN). The tibia of the sheep was used as an acute fracture model. The fracture and nailing procedure was followed by intravital staining with Procion red. The effects on cortical perfusion (Procion red staining) were addressed in polymer embedded sections and cryosections. Sudan III stained cryosections were evaluated with respect to the cortical fat distribution. After irrigation and suction minute amounts of fat were observed in the cortex, whereas after non-reamed nailing the endosteal third of the cortical bone was penetrated with fat. Non-reamed nailing acutely showed better perfusion in the endosteal tenth and periosteal third of the cortical bone, after irrigation and suction reaming perfusion was preserved to a lesser degree. Irrigation and suction significantly reduces fat intravasation, and thus the danger of system-wide damage. Therefore, the Reamer/Irrigator/Aspirator is as efficient as its experimental predecessors.

Treatment of recalcitrant, multiply operated tibial nonunions with the RIA graft and rh-BMP2 using intramedullary nails

Nonunions of the tibia continue to present some of the most difficult challenges in orthopaedic fracture care. Whether the consequence of the initial presenting injury, co-morbidity or subsequent attempts at fixation, the biological environment is often compromised. Compounding this problem is a lack of consensus on the best approach to addressing nonunited tibia fractures, placing them at risk for multiple, and sometimes ill-informed attempts at nonunion repair. We present nine cases of recalcitrant tibial nonunions which had previously undergone 4 or more attempts at repair treated with a protocol using RIA graft, rh-BMP2 and intramedullary nail fixation.

A cadaver model evaluating femoral intramedullary reaming: a comparison between new reamer design (Pressure Sentinel) and a novel suction/irrigation reamer (RIA)

OBJECTIVE

To compare the intramedullary pressures developed during reaming of cadaveric femurs with the Synthes Reamer/Irrigator/Aspirator (RIA) reamer and the Zimmer Pressure Sentinel (PS) reamer, controlling for the force and speed of reaming.

METHOD

Fifteen matched pairs of frozen unpreserved femurs were used in the study. Two pressure transducers and two thermocouples were screwed into holes drilled into the femoral shaft. The femurs were stabilized in the vertical position by mechanically attaching them to a custom jig equipped with a load cell to detect the vertical component of force applied to the reamer. Proximally a linear voltage displacement transducer (LVDT) was attached to the reamer to record the continuous position of the reamer. All femurs were reamed to a diameter 2 mm larger than the narrowest point of the canal. Proximal and distal pressures, proximal and distal temperatures, applied vertical force and displacement were measured continuously throughout the reaming process. Maximum and minimum, and average proximal and distal pressures for each reamer were obtained and compared using paired t-tests. Averages were also calculated and compared in the same manner. A p-value of <0.05 was considered statistically significant.

RESULTS

The maximum, minimum and average intramedullary pressures during reaming were significantly lower with the RIA system than the PS reamer. In general, the pressures produced by the RIA system were consistently below atmospheric pressure for the majority of the reaming time. This was not true for the PS system. No appreciable temperature changes were observed during any of the trials.

CONCLUSION

The RIA reaming system significantly reduces the intramedullary pressures produced during the reaming process compared to the PS reaming system.

Comparison of RIA and conventional reamed nailing for treatment of femur shaft fractures

INTRODUCTION

The standard of care for femoral diaphysis fractures is sequentially reamed, locked, intramedullary nails. However, in the polytraumatized patient perioperative complications such as fat embolism syndrome (FES) and acute respiratory distress (ARDS) are well chronicled. The reamer irrigator aspirator (RIA)has been theorized to minimize such phenomena.

METHODS

A retrospective study comparing conventional reamed nailing for femur fractures versus those treated with the RIA was conducted. From January 2005 to September 2006, 156 patients treated at our institution with an intramedullary nail met inclusion criteria. There were sixty-six patient treated with conventional reaming (group A) and ninety patients treated with the RIA (group B). The main outcome measures included length of hospital stay, rate of ARDS, pneumonia, ventilatory failure, overall pulmonary complications, healing rate and death.

RESULTS

No significant differences were found between groups with regard to patient demographics, injury severity and the incidence of head/chest trauma. In addition, no differences were found in length of hospital stay, length of ICU stay or mechanical ventilation. Overall pulmonary complications occurred in 11% (group A) and 16% (group B) respectively (p = 0.48). No fatalities were found in group A while there were four in group B, 4% (p = 0.14). No significant differences were found in delayed union versus nonunion rate between groups, while overall healing complications were seen in 7% and 14% of patients (p = 0.35) in groups A and B respectively.

CONCLUSION

No statistical significance was reached with regard to pulmonary complications, healing rates or death. However, we were unable to demonstrate favorable physiologic lung parameters with RIA use compared to conventional reaming as has been described in previous animal studies. We found a trend toward more healing complications in the RIA group, but this was not statistically significant. Further study is warranted.

Biomechanical effects of harvesting bone graft with the Reamer/Irrigator/Aspirator on the adult femur: a cadaver study

OBJECTIVES

Test the biomechanical properties of femurs that have undergone reaming with the Reamer Irrigator Aspirator (RIA) device with an aim to prove no difference in torsional strength between matched pairs.

METHODS

Intact femurs were harvested from embalmed cadavers, representing 19 matched pairs. One femur from each pair was randomly selected to undergo reaming using the RIA to 15 mm. The bones were then cut and potted using a uniform jig for testing. Each specimen was tested in torsion and torsional stiffness was calculated for each pair. Samples were loaded until fracture or 11 3 N·m of torque.

RESULTS

Nine of the reamed specimens and 13 of the unreamed samples remained intact until the machine limit of 113 N·m was reached, representing approximately four times the peak torque of 30N·m seen with stair climbing [Garino J, Beredjiklian P. Core Knowledge in Orthopaedics: Adult Reconstruction and Arthroplasty. Chapter 1, page 33. Mosby, 2007]. Mean torsional stiffness for the reamed group was 532.1 N·m/rad (SD = 208.2), and the unreamed was 546.2 N·m/rad (SD=206). Torsional load capacity was calculated for all specimens and compared in groups in which both reamed and unreamed specimens failed. In these five groups, mean load capacity was 80.6 Nm (SD = 9.5) for the reamed group, and 85 Nm (SD = 16.1) for the unreamed group.

CONCLUSIONS

17 of our reamed specimens and all of our unreamed specimens withstood normal physiologic load seen with stair climbing. In addition, 16 of 19 reamed specimens remained intact at twice this load. The specimen in the reamed group with the lowest torsional load capacity was eccentrically reamed in the distal anterior cortex highlighting potential complications. Given these findings, reaming the cortex of the femur with the RIA device for the purpose of harvesting bone graft does not appear to dramatically diminish the mechanical properties of the cortex or require postoperative weight bearing restrictions. However, careful attention must be paid to technique as eccentric reaming either proximally or distally may result in catastrophic failure. Careful attention must be paid to the use of irrigating fluid and post operative blood loss, and a thorough discussion of risk factors including postoperative fracture should be covered when obtaining informed consent.

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.

Autogenous bone graft harvest using reamer irrigator aspirator (RIA) technique for tibiotalocalcaneal arthrodesis

Tibiotalocalcaneal arthrodesis is a technically demanding procedure that can be associated with a high number of complications, including nonunion. Bone grafting is commonly used in arthrodesis procedures to decrease the risk of nonunion. In this article, we describe a technique that uses a reamer-irrigator-aspirator (RIA) method for procurement of autogenous bone graft for use in tibiotalocalcaneal arthrodesis fixated with a retrograde intramedullary nail. Using the RIA technique, autogenous bone graft can be readily obtained without the need for additional incisions and dissection, thereby minimizing the need for additional sources of bone graft.

Biological rationale for the intramedullary canal as a source of autograft material

Bone harvested by intramedullary reaming offers a minimally invasive alternative to harvesting bone from the iliac crest, which has long been considered the gold standard for autogenous bone grafting. The biologic potential of intramedullary reaming material has been studied both in vitro and in vivo. The material provides osteogenic, osteoinductive, and osteoconductive properties that are comparable to the material harvested from the iliac crest. In addition to the ability to obtain a large volume of bone, the graft harvested by the Reamer-Irrigator-Aspirator has been shown to be rich in growth factors, including BMP-2, TGF-beta1, IGF-I, FGFa, and PDGFbb.

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

Treatment of large segmental defects using conventional autogenous iliac crest bone graft can be limited by volume of cancellous bone and donor site morbidity. The reamer-irrigator-aspirator (RIA) technique allows access to a large volume of cancellous bone graft containing growth factors with potency equal to or greater than autograft material from the iliac crest. The purpose of this study was to evaluate the effectiveness of RIA-harvested autogenous bone graft for treating large segmental defects of long bones.

Surgical techniques: how I do it? The Reamer/Irrigator/Aspirator (RIA) system

Although reamed intramedullary nailing has long been considered a safe procedure, pulmonary complications have been reported in some groups of patients. Concerns over fat embolisation, adult respiratory distress syndrome (ARDS), and sudden intraoperative death have prompted some authors to question whether the benefits of reaming are outweighed by its potential adverse effects to the patient. In response to these complications, recent evaluations have focused on alternative systems that reduce intramedullary pressure during reaming. The Reamer/Irrigator/Aspirator (RIA) system (Synthes, Inc., West Chester, PA) was developed as a simultaneous reaming and aspiration system to reduce the intramedullary pressure, heat generation, operating time, and systemic effects of reaming. It was designed with an aggressive one-pass reamer head which is connected to a hand-held reamer via a drive shaft, simultaneously irrigating and aspirating femoral canal contents during reaming, thus preventing thermal necrosis and fat embolisation. After its early use, investigators examined the "aspirate" captured by the RIA which appeared to be loaded with osteogenic substrates. This discovery revealed a second potential use for the RIA-a bone graft harvester. The different design characteristics and technicalities of the RIA system necessitate a deep and clear understanding of its technique, a meticulous preoperative planning and a strict adherence to its principles intraoperatively. We present our current approach to the use of the RIA system, including the preoperative planning, the details of the operative procedure, the pitfalls and the potential complications that could be encountered.

Intramedullary nailing of the femur: current concepts concerning reaming

Intramedullary fixation has advanced to the standard of care for fractures of the femoral shaft. Current controversies center on whether to prepare the intramedullary canal by reaming, particularly in certain subsets of patients. As understanding of the local and systemic effects of reaming deepens, there is a role for maximizing the benefits of intramedullary preparation before nail fixation, while attempting to minimize the major disadvantages of this technique. Several treatment strategies have emerged to address the downsides of intramedullary reaming. The purpose of this review is to discuss the history and current knowledge of intramedullary reaming with respect to problems associated with its use and the evolution of treatment modalities and their clinical applicability for orthopaedic trauma care.