Can the Reamer/Irrigator/Aspirator System replace anterior iliac crest grafting when treating long bone nonunion?

Centromedullary nailing during the second stage of induced membrane (Masquelet) for tibia septic nonunion enables bone union to be achieved without increasing the risk of recurrence of infection, with an earlier return to weight-bearing

INTRODUCTION

Septic nonunion is one of the most feared complications in traumatology. Two-stage management using the induced membrane technique is a validated treatment option, but to date there is no consensus on the ideal type of osteosynthesis for the second stage of surgery. The aim of this study was to compare the results of two-stage treatment of tibial septic nonunion, depending on the type of osteosynthesis used.

HYPOTHESIS

Our hypothesis was that internal centromedullary nailing osteosynthesis during the second stage of management of septic tibia nonunion would achieve bone union and healing of the infection, while allowing faster resumption of weight-bearing without increasing the complication rate.

MATERIAL & METHODS

This was a retrospective monocentric continuous comparative study including all 2-stage tibial septic nonunions treated from January 2008 to July 2018, with a minimum follow-up of 18 months. Healing and septic reactivation rates, as well as time to union and weight-bearing on the limb, were compared according to the type of osteosynthesis used. Primary success was defined as recovery from septic nonunion, and secondary success as recovery after at least one additional surgical procedure.

RESULTS

Forty-nine patients were included, aged 39.5 +/- 14.8 years. Primary and secondary success rates were 77.6% (38/49) and 87.8% (43/49), with a mean follow-up of 29.4 +/- 11.3 months. Internal osteosynthesis did not lead to more septic reactivation than external stabilization (p = 0.49), while allowing union within the same deadlines. Osteosynthesis with a centromedullary nail allowed earlier weight-bearing (1.5 +/- 0.9 months) vs. plate (4.8 +/- 1.5) or vs. external fixator (5.3 +/- 1.8) (p < 0.001).

CONCLUSION

Secondary conversion to internal osteosynthesis during the second stage of nonunion cure allows consolidation in same delays, without increasing the risk of infectious recurrence. It also enables faster weight-bearing on the operated limb, particularly in the case of centromedullary nailing.

LEVEL OF EVIDENCE

III; comparative study.

Secondary removal of intramedullary metal debris from a defective Reamer-Irrigator-Aspirator (RIA) reamer head: A case report

The Reamer-Irrigator-Aspirator (RIA) device represents a safe and efficient method to harvest autologous bone for grafting. However, hardware failure may occur, for example by breakage of the reamer head with metal debris remaining in the intramedullary canal. This case report describes the uncomplicated secondary removal of femoral intramedullary metal debris from a broken RIA reamer head; three weeks after the final surgery of a two-stage Masquelet procedure for the treatment of posttraumatic segmental bone loss at the tibia.

[Modified Masquelet technique : Technique of the induced membrane in the course of time]

The reconstruction of long bone defects as a result of primary traumatic, secondary infection or tumor-related loss of substance continues to represent a surgical challenge. Callus distraction via segment transport, vascularized bone transfer and the induced membrane technique (IMT) are established methods of reconstruction. In recent decades IMT has experienced increasing popularity due to its practicability, reproducibility and reliability. At the same time, the original technique has undergone numerous modifications. The results are correspondingly heterogeneous. This overview is intended to explain the basic principles of IMT and to provide an overview of the various modifications and their complications.

Development and verification of a novel bone collector with automatic size separating function for orthopedics surgery

BACKGROUND

Autologous bone dust can be filled in bone defects to promote effective bone healing but typically it is lost when using suction during surgery. The aim of this study was to develop a novel bone collector that can be used to collect bone chips/dust of varying sizes without changing current surgical procedures.

RESEARCH DESIGN AND METHODS

This collector was designed to connect to a surgical continuous suction system and comprised a plate filter with a 3 mm hole and featured a taper filter with a mesh size of 0.27 mm for the separation and collection of both coarse and fine bone chips/dust. The bone collector was manufactured using nylon 3D printing and plastic injection with biocompatible materials.

RESULTS

The bone collector functional test revealed high bone chip collection efficiency (93%) with automatic size separation function. Low (3.42%) filtration errors showed that most of the water can be drained smoothly from the bone collector. In clinical usability testing, bone collectors can provide functions demonstrated in in vivo spinal fusion and femoral fracture surgeries with different bone grafting size requirements.

CONCLUSIONS

The novel bone collector has been validated as a viable and effective surgical device, offering surgeons an additional option to enhance patient outcomes.

Fourteen-Year Follow-Up of a Patient With a Hydroxyapatite Ceramic Matrix Reconstruction of and a Bone Graft for a Critical-Size Cortical Bone Defect: A Case Report

A 42-year-old man diagnosed with chondrosarcoma of the proximal femur underwent limb salvage by compartmental excision of the lesion and reconstruction with a custom-made hip prosthesis. The critical-size defect in the proximal femur was reconstructed with ceramic hemicylinders that were tied in place with sutures and augmented with two fibular strut grafts and an autologous cancellous iliac crest bone graft. A fourteen-year follow-up of the same case revealed that substituted ceramic matrices can be converted into dynamic, metabolically active, living bone.

Comparison of reamer irrigator aspirator (RIA) suspension versus bone marrow aspirate concentrate (BMC) for percutaneous treatment of long bone nonunions-A preclinical canine model

OBJECTIVE

To compare the bone healing effects of percutaneously delivered bone marrow aspirate concentrate (BMC) versus reamer irrigator aspirator (RIA) suspension in a validated preclinical canine ulnar nonunion model. We hypothesized that BMC would be superior to RIA in inducing bone formation across a nonunion site after percutaneous application. The null hypothesis was that BMC and RIA would be equivalent.

METHODS

A bilateral ulnar nonunion model (n= 6; 3 matched pairs) was created. Eight weeks after segmental ulnar ostectomy, RIA from the ipsilateral femur and BMC from the proximal humerus were harvested and percutaneously administered into either the left or right ulnar defect. The same volume (3 ml) of RIA suspension and BMC were applied on each side. Eight weeks after treatment, the dogs were euthanized, and the nonunions were evaluated using radiographic, biomechanical, and histologic assessments.

RESULTS

All dogs survived for the intended study duration, formed radiographic nonunions 8 weeks after segmental ulnar ostectomy, and underwent the assigned percutaneous treatment. Radiographic and macroscopic assessments of bone healing at the defect sites revealed superior bridging-callous formation in BMC-treated nonunions. Histologic analyses revealed greater amount of bony bridging and callous formation in the BMC group. Biomechanical testing of the treated nonunions did not reveal any significant differences.

CONCLUSION

Bone marrow aspirate concentrate (BMC) had important advantages over Reamer Irrigator Aspirator (RIA) suspension for percutaneous augmentation of bone healing in a validated preclinical canine ulnar nonunion model based on clinically relevant radiographic and histologic measures of bone formation.

Efficacy and safety of autologous or allogeneic mesenchymal stromal cells from adult adipose tissue expanded and combined with tricalcium phosphate biomaterial for the surgical treatment of atrophic nonunion of long bones: a phase II clinical trial

BACKGROUND

Autologous bone grafting is the standard treatment for the surgical management of atrophic nonunion of long bones. Other solutions, such as bone marrow mesenchymal stem cells (BM-MSC) combined with phospho-calcium material, have also been used. Here we evaluate the safety and early efficacy of a novel procedure using autologous or allogenic adipose tissue mesenchymal stromal cells (AT-MSC) seeded in a patented tricalcium phosphate-based biomaterial for the treatment of bone regeneration in cases of atrophic nonunion.

METHODS

This was a prospective, multicentric, open-label, phase 2 clinical trial of patients with atrophic nonunion of long bones. Biografts of autologous or allogenic AT-MSC combined with a phosphate substrate were manufactured prior to the surgical procedures. The primary efficacy was measured 6 months after surgery, but patients were followed for 12 months after surgery and a further year out of the scope of the study. All adverse events were recorded. This cohort was compared with a historical cohort of 14 cases treated by the same research team with autologous BM-MSC.

RESULTS

A total of 12 patients with atrophic nonunion of long bones were included. The mean (SD) age was 41.2 (12.1) years and 66.7% were men. Bone healing was achieved in 10 of the 12 cases (83%) treated with the AT-MSC biografts, a percentage of healing similar (11 of the 14 cases, 79%) to that achieved in patients treated with autologous BM-MSC. Overall, two adverse events, in the same patient, were considered related to the procedure.

CONCLUSIONS

The results of this study suggest that AT-MSC biografts are safe for the treatment of bone regeneration in cases of atrophic nonunion and reach high healing rates.

TRIAL REGISTRATION

Study registered with EUDRA-CT (2013-000930-37) and ClinicalTrials.gov (NCT02483364).

Approach to Tibial Shaft Nonunions: Diagnosis and Management

The tibia is the most common long bone at risk for nonunion with an annual incidence ranging from 12% to 19%. This topic continues to be an area of research as management techniques constantly evolve. A foundational knowledge of the fundamental concepts, etiology, and risk factors for nonunions is crucial for success. Treatment of tibial shaft nonunions often requires a multidisciplinary effort. This article provides guidance based on the most recent literature that can be used to aid the treating provider in the diagnosis, workup, and management of tibial shaft nonunions.

Transverse subtrochanteric shortening osteotomy with double tension-band fixation during THA for Crowe III-IV developmental dysplasia: 12-year outcomes

BACKGROUND

When performing total hip arthroplasty in patients with severe developmental dysplasia, shortening the femur facilitates reduction while also preventing sciatic or crural nerve injury and excessive length of the operated limb. No consensus exists about the optimal type of implant and best internal fixation procedure, two parameters that directly govern the risk of the most common intraoperative and postoperative complications (diaphyseal fractures, dislocation, non-union). To minimise these risks, we developed a technique combining a transverse subtrochanteric shortening osteotomy, a long ovoid-profiled, cementless stem anchored in the metaphysis, and double tension-band wiring for internal fixation. The primary objective of this study was to evaluate the outcomes of this technique with emphasis on (i) complications and femoral implant survival, (ii) clinical outcomes (functional scores and lower-limb length inequality [LLLI]), and time to healing.

HYPOTHESIS

Our technique is associated with low rates of intraoperative and postoperative complications.

MATERIAL AND METHODS

This single-centre retrospective cohort study included patients who underwent THA with a transverse subtrochanteric shortening osteotomy and fixation using double tension-band wiring to treat severe (Crowe III or IV) developmental hip dysplasia. The femoral implant was a long, ovoid, cementless stem fully coated with hydroxyapatite. We collected the intraoperative and postoperative complications, survival, LLLI, functional scores (Harris Hip Score [HHS] and Forgotten Joint Score [FJS]), patient satisfaction, and radiographic outcomes.

RESULTS

The study included 31 hips in 25 patients. Two patients (2/31 hips, 6.5%) were lost to follow-up, leaving 29 hips for the analysis of postoperative outcomes. Mean follow-up was 13.7±4.2 years (range, 5.8-18.3 years). The four intraoperative complications (4/31, 12.9%) consisted fracture of the diaphysis (2/31, 6.5%), fracture of the greater trochanter (1/31, 3.2%), and sciatic nerve injury followed by a full recovery (1/29, 3.4%). The 8 (8/29, 27.5%) postoperative complications consisted of dislocation (2/29, 6.9%), stem subsidence (2/29, 6.9%), and non-union (4/29, 13.8%). Femoral implant survival at last follow-up was 87.1% (95% CI, 76.1-99.7). The mean HHS increased from 39.6±12.0 (range, 14-61) before surgery to 81.7±13.2 (range, 48-100) at last follow-up (p<0.01). The FJS at last follow-up indicated that the joint was forgotten in 14/29 (48.2%) cases and caused only acceptable symptoms in 9/29 (31.0%) of cases. Clinically significant (≥ 1cm) LLLI was present in 8/29 (27.6%) patients postoperatively compared to 19/29 (65.5%) preoperatively. The mean LLLI decreased from 20.8±19.7mm (range, 0-60mm) to 5.0±7.3mm (range, 0-30mm). Mean time to healing was 4.3±2.4 months (range, 2-11 months).

CONCLUSION

Regarding these complex procedures, this technique was associated with low rates of intraoperative fractures and early postoperative complications. However, femoral stem survival was shorter than in earlier studies and the non-union rate was high, despite satisfactory functional and clinical outcomes.

LEVEL OF EVIDENCE IV

Scooping Technique to Acquire Cancellous Bone for Grafting in the Masquelet Procedure: A Retrospective Study

Background

The Masquelet procedure is effective in overcoming large bone defects; however, the limited number of cancellous bone and donor site complications remains a challenge. We developed a scooping technique to harvest sufficient cancellous bone from iliac crests for grafting during the Masquelet procedure. We hypothesized that this method would be efficient and safe.

Methods

This retrospective study included 13 patients who underwent the Masquelet procedure with cancellous bone grafting using the scooping technique. The following parameters were observed: (1) duration and total volume of cancellous bone extraction; (2) amount of bleeding and drainage fluid, and Visual Analog Scale (VAS) score of pain at the donor site during different periods; and (3) complications and bone regeneration at the ilium at the final follow-up.

Results

The median follow-up duration was 17 months. There were 3 unilateral and 10 bilateral extraction sites. The mean total amount extracted, extraction duration, bleeding, and drainage were 39 mL, 23 min, 49 mL, and 44 mL, respectively. Only three patients felt pain (VAS score: 1 point) at the final follow-up. Postoperatively, one case each of hematoma and lateral femoral cutaneous nerve injury supervened, and no infections or other complications occurred. The last computed tomography examination showed varying degrees of bone regeneration in the ilium.

Conclusion

The scooping technique for the iliac crest produced a substantial amount of autogenous cancellous bone using a small incision. It retained the appearance and morphology of the ilium with few complications. We believe it is a successful and safe option for treating bone defects.

Complications associated using the reamer-irrigator -aspirator (RIA) system: a systematic review and meta-analysis

INTRODUCTION

Complications associated with the application of the Reamer-irrigator-Aspirator (RIA) system are described in the literature. However, to date a systematic review and meta-analysis to assess prevalence of complications associated with the use of the RIA system have not been conducted.

MATERIALS AND METHODS

The review is registered with PROSPERO (CRD42021269982). MEDLINE, the Web of Science Core Collection, and Embase were searched from the inception to 10 August 2021. The primary objective was to assess complications and blood loss associated with the use of the RIA system.

RESULTS

Forty-seven studies involving 1834 procedures performed with the RIA system were finally included. A total of 105 complications were reported, with a pooled estimated overall prevalence of 1.7% with a 95% confidence interval (CI) of 0.40 to 3.60, with cortex perforation being the largest reported complication with a total of 34 incidences. A significant subgroup difference was observed (p = 0.02). In subgroup 1 (bone graft harvesting), complication prevalence was 1.4% (95% CI 0.2-3.4); in subgroup 2 (clearance intramedullary canal) it was 0.7% (95% CI 0.00-6.30) and in subgroup 3 (reaming with RIA system prior to nail fixation) 11.9% (95% CI 1.80-26.40). No statistically significant difference for tibia and femur as RIA system application site was observed (CI 0.69-4.19). In studies reporting blood loss, a mean volume of 803.29 ml, a mean drop of hemoglobin of 3.74 g/dl and a necessity of blood transfusion in 9.72% of the patients were observed.

CONCLUSIONS

The systematic review and meta-analysis demonstrate a low overall prevalence rate of complications associated with the RIA system. However, especially the risk of cortical perforation and the frequently reported relevant intraoperative blood loss are complications that should be anticipated in perioperative management and ultimately considered when using the RIA system.

A review of the Masquelet technique in the treatment of lower limb critical-size bone defects

The need for bone tissue to heal effectively is paramount given its role in the mechanical support of tissues. Bone has a very good natural healing potential in comparison with most other tissue types, largely regenerating to its pre-injury state in the vast majority of cases. Certain factors such as high energy trauma, tumour resection, revision surgery, developmental deformities and infection can lead to the formation of bone defects, where the intrinsic healing potential of bone is diminished owing to bone loss. Various approaches to resolving bone defects exist in current practice, each with their respective benefits and drawbacks. These include bone grafting, free tissue transfer, Ilizarov bone transport and the Masquelet induced membrane technique. This review focuses on evaluating the Masquelet technique, discussing its method and underlying mechanisms, the effectiveness of certain modifications, and its potential future directions.

Masquelet's induced membrane technique associated with Reamer Irrigation Aspiration grafting and intramedullary Nailing (MaRIAN) for chronic diaphyseal osteomyelitis of the lower limb

INTRODUCTION

Masquelet's induced membrane technique offers a definitive contribution to the treatment of diaphyseal osteomyelitis. To overcome its drawbacks while maintaining its principles, technical modifications have been proposed: antibiotic cement, femoral intramedullary autograft harvested by RIA (Reamer Irrigation Aspiration) and interlocking nails.

MATERIAL AND METHOD

This retrospective study gathered patients with chronic osteomyelitis of the femur or tibia. The first surgical stage consisted of bone resection in the healthy zone and use of a gentamicin cement spacer to fill the bone defect. The second stage consisted of the placement of a statically locked intramedullary nail associated with a bone autograft using the RIA technique.

RESULTS

Among this group of 12 men with diaphyseal osteomyelitis; 9 tibial and 2 femoral, and 1 knee nonunion, the mean bone defect was 7.3cm (±6.7). The mean time between the 2 stages was 2.7months (±3) with a mean antibiotic period of 3.25weeks (±3). There was a femoral diaphyseal fracture at the donor site, and a wrong trajectory intraoperatively during the RIA. Two patients with tibial nonunion presented with nail rupture without septic recurrence. A septic recurrence was healed by removal of the nail. At a minimum follow-up of 18months, with an average of 5years, consolidation was complete without infectious recurrence. Despite the statistical weakness related to the size of the cohort, the resumption of early weight bearing (OR=-7.68 95% CI [-13.33 to -2.08] (p=0.01)) and nail dynamization seemed to have an impact on the formation of complete consolidation (OR=-0.86 95% CI [-1.39 to -0.33] (p=0.007)).

DISCUSSION AND CONCLUSION

This short series, compared to the literature, demonstrated that the proposed technical modifications improved the overall management of this rare and challenging condition while maintaining the reliability of the original technique. Dynamization was also seen to be of particular interest.

LEVEL OF EVIDENCE

IV, retrospective study.

The Reamer-Irrigator-Aspirator (RIA) System for the treatment of aseptic femoral nonunions: Report of two cases and literature review

Femoral shaft nonunions are disabling complications of fractures, with relevant socioeconomic and psychological impact. The incidence of femoral shaft nonunions is not negligible, ranging between 1% and 10% after intramedullary nailing, but can exceed 20% in case of subtrochanteric fractures. Treatment options are influenced by pathomechanical, anatomical, and clinical factors. Hypertrophic nonunions are usually treated by enhancing stability of fixation, while atrophic nonunions require additional biological stimulation to achieve bone union. The Reamer-Irrigator-Aspirator (RIA) System® was developed to reduce intramedullary pressure and heat generation during intramedullary reaming, thus preventing thermal necrosis and decreasing the risk of fat embolism. The RIA System allows to provide large volumes of high-quality morselized autologous bone, that has shown high osteogenetic and osteoinductive properties. Therefore, its use has been expanded as a valuable source of autologous bone graft for the treatment of large bone defects of different nature. In this article, we present two cases of complex femoral nonunions treated with the use of the RIA System. A review of the published literature on the treatment of femoral nonunions with RIA was also performed. Core tip: In case of atrophic nonunions, the RIA System can be used to obtain biologically active tissue to enhance bone healing. Despite the absence of high-quality studies focused on femoral nonunions, the efficacy of RIA is well-known and orthopaedic surgeons should be aware of this powerful tool.

The Free Tissue Transfer-Masquelet-Reamer-Irrigator-Aspirator Bone Graft Orthoplastic Approach for Lower Extremity Reconstruction

SUMMARY

The management of critical-sized bone and soft-tissue defects of the lower extremity poses unique challenge to reconstructive surgeons. The aim of this article is to present the authors' current orthoplastic approach for the management of extended (more than 6 cm) osteocutaneous defects of the lower extremity, based on a sequential combination of two stages: free flap for soft-tissue coverage and the Masquelet technique (first step) followed by reamer-irrigator-aspirator cancellous bone graft and definitive osteosynthesis (second step). This study was a single-center observational retrospective review of prospectively collected data. Adult patients (>18 years of age) with segmental bone loss of the lower extremity caused by acute trauma (Gustilo type IIIB fracture) or nonunion (septic/aseptic) who were treated with the free flap for soft-tissue coverage-Masquelet technique-reamer-irrigator-aspirator approach between January of 2017 and December of 2020 were included. Time of consolidation and early and late complications were recorded. A total of 11 patients (nine male patients and two female patients) with a mean age of 45.8 years were identified. The average bone gap length (standard deviation) was 87.3 (24.9) mm. An anterolateral thigh flap was harvested in all cases. The average duration of the first stage (i.e., time from antibiotic cement spacer placement and free flap to time of bone grafting) was 50.4 days (range, 40 to 62 days). Bone consolidation was achieved in all cases after an average period (standard deviation) of 20.4 (3.3) weeks, with acceptable functional outcomes. The free flap for soft-tissue coverage-Masquelet technique-reamer-irrigator-aspirator approach could be considered a viable option in patients with segmental critical-sized bone defects associated with a large soft-tissue deficit of the lower extremity.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

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.

Quantitative Analysis of Growth Factors From Cancellous Bone Graft Collected With a Reamer-Irrigator-Aspirator System From Native Long Bones Versus Previously Reamed Long Bones

OBJECTIVE

Collection of bone graft with the Reamer-Irrigator-Aspirator (RIA) system has become common practice across the field of orthopaedic surgery. While RIA bone graft is typically obtained from native long bones, grafting material can likewise be harvested from long bones that have previously undergone the placement and removal of an intramedullary nail, a process termed re-reamed RIA (RRR). The purpose of this study was to evaluate the total protein and growth factor concentrations present in native-RIA (NR) compared with RRR samples.

METHODS

NR and RRR bone grafts were collected intraoperatively with the RIA system and processed to evaluate both the aqueous and the hard tissue components. Total protein concentration and specific growth factors were analyzed using standard bicinchoninic acid and multiplex assays, respectively. Analyte levels were then normalized to the total amount of protein detected.

RESULTS

Total protein levels were comparable between NR and RRR samples for both the aqueous filtrate and the hard tissue samples. When normalized, while levels of bone morphogenic protein-2 and vascular endothelial growth factor were comparable in the hard tissue component, the aqueous filtrate from the RRR sample was found to have elevated levels of growth factors, with bone morphogenic protein-2 reaching statistical significance.

CONCLUSIONS

This study demonstrates that ample protein is found within both NR and RRR samples, with comparable or elevated levels of osteogenic growth factors found within RRR samples. Future, larger, prospective studies will be required to evaluate the osteogenic potential and clinical efficacy of NR and RRR cancellous bone grafts to validate their equivalency.

RIA versus iliac crest bone graft harvesting: A meta-analysis and systematic review

BACKGROUND

Reamer-Irrigator-Aspirator (RIA) of long bones is increasingly being used as an alternative to iliac crest harvesting for bone-grafts. This meta-analysis compares both harvesting techniques with regard to donor site morbidity, healing potency and implantation site morbidity.

METHODS

PubMed/Medline/Embase/CENTRAL/CINAHL were searched for both randomized clinical trials (RCT) and observational studies. Effect estimates were pooled across studies using random effects models and presented as weighted odds ratio (OR) with corresponding 95% confidence interval (95%CI).

RESULTS

A total of 5 studies were included. RIA carries a lower risk for chronic pain (0% versus 14.2%, OR 0.08, 95% CI 0.02 - 0.35) and infection (1% versus 5.9%, OR 0.29, 95% CI 0.09- 0.9) at the donor site compared to iliac crest harvesting. Iliac crest bone-harvesting has an inherent additional risk of neuropraxia of the lateral femoral cutaneous nerve and numbness of the scar which is not encountered in RIA harvesting. Risk for other reported complications such as hematoma and iatrogenic fractures appear equal in both groups. The clinical healing potential of both bone grafts, in terms of union rate (OR 1.53, 95%CI 0.62 - 3.75) at the implantation site and time-to-union (MD 0.44 months, 95%CI -1.72 - 0.83), seems equal.

CONCLUSION

The main difference between RIA and iliac crest bone graft harvesting is the considerable higher risk of chronic pain of the pelvic procedure. Although risk for infection was also higher for the iliac crest group, the absolute difference is relatively small. Evidence suggests an equal healing potential of the grafts themselves irrespective of harvesting method.

Safety and efficacy of a novel retrograde route for femoral bone graft harvesting by Reamer-Irrigator-Aspirator: a pilot study on 24 patients

Background

The Reamer–Irrigator–Aspirator system was initially developed to reduce fat embolism and thermic necrosis during reamed intramedullary nail fixation of femoral shaft fractures. Currently, this system is used in extended applications including accessing large volume of autologous bone graft, as alternative for iliac crest harvesting. Antegrade femoral bone graft harvesting using the Reamer-Irrigator-Aspirator system is considered the standard technique. The aim of our study is to evaluate the efficacy (bone graft volume) and the complications (blood loss, postoperative pain, and incidence of iatrogenic fractures) of the Reamer–Irrigator–Aspirator system through the retrograde femoral route in a series of patients with post-traumatic bone defects or nonunions.

Methods

A non-controlled single center retrospective observational cohort study was conducted in a level1 trauma center to evaluate all patients who were treated using the RIA system. Between November 2015 and May 2019, 24 patients (8 women and 16 men; mean age: 41 years [range 27–55 years]) with bone defects or nonunions underwent bone graft harvesting using the Reamer–Irrigator–Aspirator system through retrograde femoral route. Postoperative pain, complications, and bone graft volume were analyzed. Inclusion criteria was patients older than 18 years with a diagnosis of post-traumatic bone defect or associated tibial or femoral nonunion, with minimum 6-months follow, treated using the RIA. We hypothesized that the retrograde route of the RIA system is a safe and efficacious method for bone harvesting.

Results

The average volume of collected graft was 45 cc (range 30–60 cc). In 83% of the cases, bone grafting was sufficient, while in 17% it was necessary to add iliac crest bone graft to completely fill the bone defect. A mean drop in postoperative hemoglobin of 4.1 g / dL (range 0.5–6.0 g / dL) was evidenced. In 4 cases (33%), a unit of packed red blood cells was required. Regarding postoperative pain, visual analogue scale after 3 months postoperatively was 1.6 in average. After 6 months, the value has decreased to 0.4. There were no perioperative or postoperative complications at 6-month follow-up.

Conclusion

In this limited case series, large volumes of bone graft were harvested using the retrograde route of the RIA system and there were no intra-/ postoperative complications observed at 6-month follow-up. Therefore this novel technique appears safe and efficacious.

However, it’s important to highlight that future prospective controlled studies are necessary to validate the insights from this pilot study.

Outcomes and complications of the reamer irrigator aspirator versus traditional iliac crest bone graft harvesting: a systematic review and meta-analysis

BACKGROUND

The reamer irrigator aspirator (RIA) is a relatively recent device that is placed in the medullary canal of long bones to harvest a large volume of bone marrow, which is collected in a filtered canister. This study compares outcomes and complications of the RIA versus a traditional iliac crest bone graft (ICBG) for the treatment of bone defects.

METHODS

This meta-analysis was conducted according to the PRISMA guidelines. The Embase, Google Scholar, PubMed, and Scopus databases were accessed in June 2021. All clinical trials comparing the RIA and ICBG with a minimum of 6 months follow-up were included.

RESULTS

Data from 4819 patients were collected. The RIA group demonstrated lower site pain (P < 0.0001), fewer infections (P = 0.001), and a lower rate of adverse events (P < 0.0001). The ICBG group demonstrated a greater rate of bone union (P < 0.0001). There was no difference between groups in VAS (P = 0.09) and mean time to union (P = 0.06).

CONCLUSION

The current evidence supports the use of the RIA, given its low morbidity and short learning curve.

Post-traumatic forearm bone defect reconstruction using the induced membrane technique

INTRODUCTION

The induced membrane technique, first described by Masquelet, is now well standardized, but little studied in post-traumatic forearm bone defect. The main aim of the present study was to analyze consolidation rates in this indication. The study hypothesis was that the induced membrane technique provides good consolidation results.

METHODS

We performed a retrospective assessment of our experience with 10 cases of induced membrane forearm reconstruction. The two main etiologies were acute trauma or treatment for non-union. Functional impact was assessed on range of motion and QuickDASH. The complications rate was also examined.

RESULTS

There were 3 cases of post-traumatic bone defect, and 7 of non-union treatment, including 6 septic non-unions. Mean defect size was 4.3cm. Mean interval between induced membrane stages 1 and 2 was 3.3 months. Pure cancellous iliac bone graft was systematic. Nine of the patients showed consolidation, at a mean 9.2 months; there was 1 case of non-consolidation, but no other complications. Range of motion was satisfactory; mean QuickDASH score was 22 at a mean 50.3 months' follow-up.

CONCLUSION

The induced membrane technique was reliable, reproducible and technically accessible, with good functional and radiographic results and few complications.

LEVEL OF EVIDENCE

IV; retrospective study without control group.

The optimization of pepsin processing time to balance the mechanical and biological properties of xenogeneic bone

Xenogeneic bone showed great prospects to treat large bone defects due to its bionic composition and structure, but the immunogenicity limited its wide applications. Previously, we developed a pepsin treating method to eliminate the immunogenicity of xenogeneic bone. In this study, we further investigated the effect of pepsin processing time on the biological and mechanical properties. The results indicated that increased pepsin treating time impaired the mechanical properties of xenogeneic bone. And MC3T3-E1 cells showed enhanced adhesion ability, as well as increased production of alkaline phosphatase and calcium nodulus production on the xenogeneic bone processed by pepsin for 24 hr (P24), as compared with xenogeneic bone processed by pepsin for 30 hr (P30) and 36 hr (P36). In addition, we found no significant inflammatory responses after implanting different xenogeneic bone into the intermuscular site of rats. These results suggested that xenogeneic bone processed by pepsin for 24 hr may be a preferable choice when using the xenogeneic bone as biomaterials for further researches.

Use of Osteobiologics for Fracture Management: The When, What, and How

Osteobiologics are defined as a group of natural and synthetic materials used to augment bone healing. The selection of the most appropriate osteobiologic from the growing list of available options can be a challenging task. In selecting a material, surgeons should weigh a variety of considerations, including the indication for their use (the when), the most suitable substance (the what), and the correct mode of application (the how). This summary reviews these considerations and seeks to provide the surgeon with a basis for informed clinical evidence-based decision-making in their choice of a successful option.

Musculoskeletal tissue engineering: Regional gene therapy for bone repair

Bone loss associated with fracture nonunion, revision total joint arthroplasty (TJA), and pseudoarthrosis of the spine presents a challenging clinical scenario for the orthopaedic surgeon. Current treatment options including autograft, allograft, bone graft substitutes, and bone transport techniques are associated with significant morbidity, high costs, and prolonged treatment regimens. Unfortunately, these treatment strategies have proven insufficient to safely and consistently heal bone defects in the stringent biological environments often encountered in clinical cases of bone loss. The application of tissue engineering (TE) to musculoskeletal pathology has uncovered exciting potential treatment strategies for challenging bone loss scenarios in orthopaedic surgery. Regional gene therapy involves the local implantation of nucleic acids or genetically modified cells to direct specific protein expression, and has shown promise as a potential TE technique for the regeneration of bone. Preclinical studies in animal models have demonstrated the ability of regional gene therapy to safely and effectively heal critical sized bone defects which otherwise do not heal. The purpose of the present review is to provide a comprehensive overview of the current status of gene therapy applications for TE in challenging bone loss scenarios, with an emphasis on gene delivery methods and models, scaffold biomaterials, preclinical results, and future directions.

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

Objectives

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

Patients and methods

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

Results

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

Conclusion

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

Hematopoietic Wnts Modulate Endochondral Ossification During Fracture Healing

Wnt signaling plays a critical role in bone formation, homeostasis, and injury repair. Multiple cell types in bone have been proposed to produce the Wnts required for these processes. The specific role of Wnts produced from cells of hematopoietic origin has not been previously characterized. Here, we examined if hematopoietic Wnts play a role in physiological musculoskeletal development and in fracture healing. Wnt secretion from hematopoietic cells was blocked by genetic knockout of the essential Wnt modifying enzyme PORCN, achieved by crossing Vav-Cre transgenic mice with Porcn^flox mice. Knockout mice were compared with their wild-type littermates for musculoskeletal development including bone quantity and quality at maturation. Fracture healing including callus quality and quantity was assessed in a diaphyseal fracture model using quantitative micro computer-assisted tomographic scans, histological analysis, as well as biomechanical torsional and 4-point bending stress tests. The hematopoietic Porcn knockout mice had normal musculoskeletal development, with normal bone quantity and quality on micro-CT scans of the vertebrae. They also had normal gross skeletal dimensions and normal bone strength. Hematopoietic Wnt depletion in the healing fracture resulted in fewer osteoclasts in the fracture callus, with a resultant delay in callus remodeling. All calluses eventually progressed to full maturation. Hematopoietic Wnts, while not essential, modulate osteoclast numbers during fracture healing. These osteoclasts participate in callus maturation and remodeling. This demonstrates the importance of diverse Wnt sources in bone repair.

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.

Convergence of scaffold-guided bone regeneration and RIA bone grafting for the treatment of a critical-sized bone defect of the femoral shaft

BACKGROUND

Critical-sized bone defects, mainly from trauma, infection or tumor resection are a challenging condition, often resulting in prolonged, complicated course of treatment. Autografts are considered as the gold standard to replace lost bone. However, limited amount of bone graft volume and donor-site morbidity have established the need for the development of alternative methods such as scaffold-based tissue engineering (TE). The emerging market of additive manufacturing (3D-printing) has markedly influenced the manufacturing of scaffolds out of a variety of biodegradable materials. Particularly medical-grade polycaprolactone and tricalcium phosphate (mPCL-TCP) scaffolds show appropriate biocompatibility and osteoconduction with good biomechanical strength in large preclinical animal models. This case report aims to show first evidence of the feasibility, safety, and efficacy of mPCL-TCP scaffolds applied in a patient with a long bone segmental defect.

CASE PRESENTATION

The presented case comprises a 29-year-old patient who has suffered a left-sided II° open femoral shaft fracture. After initial external fixation and subsequent conversion to reamed antegrade femoral nailing, the patient presented with an infection in the area of the formerly open fracture. Multiple revision surgeries followed to eradicate microbial colonization and attempt to achieve bone healing. However, 18 months after the index event, still insufficient diaphyseal bone formation was observed with circumferential bony defect measuring 6 cm at the medial and 11 cm at the lateral aspect of the femur. Therefore, the patient received a patient-specific mPCL-TCP scaffold, fitting the exact anatomical defect and the inserted nail, combined with autologous bone graft (ABG) harvested with the Reamer-Irrigator-Aspirator system (RIA-Synthes®) as well as bone morphogenetic protein-2 (BMP-2). Radiographic follow-up 12 months after implantation of the TE scaffold shows advanced bony fusion and bone formation inside and outside the fully interconnected scaffold architecture.

CONCLUSION

This case report shows a promising translation of scaffold-based TE from bench to bedside. Preliminary evidence indicates that the use of medical-grade scaffolds is safe and has the potential to improve bone healing. Further, its synergistic effects when combined with ABG and BMP-2 show the potential of mPCL-TCP scaffolds to support new bone formation in segmental long bone defects.

Comparing the efficacy of syngeneic iliac and femoral allografts with iliac crest autograft in a rat model of lumbar spinal fusion

BACKGROUND

Despite widespread use of femoral-sourced allografts in clinical spinal fusion procedures and the increasing interest in using femoral reamer-irrigator-aspirator (RIA) autograft in clinical bone grafting, few studies have examined the efficacy of femoral grafts compared to iliac crest grafts in spinal fusion. The objective of this study was to directly compare the use of autologous iliac crest with syngeneic femoral and iliac allograft bone in the rat model of lumbar spinal fusion.

METHODS

Single-level bilateral posterolateral intertransverse process lumbar spinal fusion surgery was performed on Lewis rats divided into three experimental groups: iliac crest autograft, syngeneic iliac crest allograft, and syngeneic femoral allograft bone. Eight weeks postoperatively, fusion was evaluated via microCT analysis, manual palpation, and histology. In vitro analysis of the colony-forming and osteogenic capacity of bone marrow cells derived from rat femurs and hips was also performed to determine whether there was a correlation with the fusion efficacy of these graft sources.

RESULTS

Although no differences were observed between groups in CT fusion mass volumes, iliac allografts displayed an increased number of radiographically fused fusion masses and a higher rate of bilateral fusion via manual palpation. Histologically, hip-derived grafts showed better integration with host bone than femur derived ones, likely associated with the higher concentration of osteogenic progenitor cells observed in hip-derived bone marrow.

CONCLUSIONS

This study demonstrates the feasibility of using syngeneic allograft bone in place of autograft bone within inbred rat fusion models and highlights the need for further study of femoral-derived grafts in fusion.

Comparison of bone morphogenetic protein and autologous grafting in the treatment of limb long bone nonunion: a systematic review and meta-analysis

BACKGROUND

Bone morphogenetic proteins (BMPs) have strong bone induction properties and can promote healing of fractures and other defects. However, BMP treatment efficacy for long bone nonunion remains controversial. The aim of this meta-analysis was to synthetically evaluate the advantages and disadvantages of BMP plus bone grafting (observation group) versus autologous bone grafting (control group) for limb long bone nonunion.

METHODS

PubMed, Embase, Web of Science, Cochrane Library, OVID, CNKI, Weipu Journal, Chinese Biomedical Literature, and WanFang were searched for randomized and non-randomized controlled trials published before November 2019. A meta-analysis of outcome indicators was performed using RevMan 5.3 and Stata 12.0.

RESULTS

Five randomized and four non-randomized controlled trials involving 30-124 cases were included, with a total of 655 nonunion cases. There were no significant group differences in postoperative healing rate, infection, and secondary operation rates (P > 0.05), but the study group demonstrated significantly shorter mean healing time (WMD = - 1.27, 95%CI - 1.67 to - 0.88, P < 0.00001), a greater frequency of excellent/good post-treatment limb function (RR = 1.18, 95%CI 1.01-1.39, P = 0.04), and lower intraoperative blood loss (P < 0.05). Alternatively, the hospitalization cost was significantly higher in the study group (P < 0.01).

CONCLUSIONS

Bone morphogenetic protein is a viable alternative to autologous bone grafting, with potential advantages of accelerated fracture healing and improved postoperative function.

Nonunions of Bisphosphonate Fractures of the Femur: Presentation, Etiopathogenesis, Diagnosis, and Operative Treatment

Patients presenting with femoral fractures and long-term use of bisphosphonate treatment are at risk of developing a delayed union and/or nonunion as a result of the atypical metabolic activity prevailing at the fracture edges of the affected extremity. The treatment of these nonunions poses a serious challenge to orthopaedic surgeons worldwide and necessitates specialized techniques and materials to design a construct that will last a long period (greater than 6 months), while still allowing weight-bearing in this elderly population. Treatment options, timing of intervention, selection of implant, and the option of bone grafting are discussed to assist the clinician to make the right decisions in these complex clinical cases.