---
title: 'The Treatment of Long Bone Nonunion & the Role of Diamond Concept'
type: 'lecture'
url: 'https://doc.social/lectures/the-treatment-of-long-bone-nonunion-the-role-of-diamond-concept'
published: '2020-12-29'
author: 'Christine Trogdon'
transcript: 'yes'
---

# The Treatment of Long Bone Nonunion & the Role of Diamond Concept

Peter Giannoudis, MD discusses the Diamond Concept and Bone Repair

## Summary

You’re invited to watch a short video created by Peter Giannoudis, MD. He’ll cover the following topics:
• Definition - Incidence of Nonunion
• Risk Factors - Pathogenesis of Nonunion
• The 'Diamond Concept' and Bone Repair
• The role of the 'Diamond Concept' as part of treatment planning
• How EXOGEN can be used within the Diamond Concept framework of bone repair

## Transcript

2,740 words · 27 min · automatically transcribed (aws-transcribe) and not checked by a person; it may contain errors, particularly in names, drugs and dosages. The recording is the source.

[0:01] Hello, my name is Peter Genoudis. I work in Leeds, England, and uh it's my pleasure today to share with you my thoughts about the treatment of Long bone nonunion, the role of Diamond Concept.
[0:15] These are my disclosures.
[0:22] And this is the outline of my talk.
[0:28] Let's start with the definition and incidence of nonunion.
[0:35] As you, as you all are aware,
[0:39] Non-union is defined in various ways.
[0:43] With a 5 55% disagreement amongst clinicians on timing.
[0:49] The FDA
[0:51] Defines it as failure to achieve union by 9 months since the injury and for which there has been no signs of healing for 3 months.
[1:02] Other investigators define nonunion as no evidence of radiological Fracture healing being present within a period of 6 months.
[1:16] In terms of the incidence of non-union, pending on the study size, patient demographics, injury location, and severity, and method of treatment.
[1:30] The overall reported incidence ranges between 2 to 30%.
[1:38] Recently, a study from Australia reported an overall incidence of 8%.
[1:51] Let's move on now to the Risk factors and pathogenesis of nonunion.
[2:03] If we look into the Risk factors of nonunion,
[2:08] We can divide them into patient-related, surgeon-related, and injury-related.
[2:20] We try to analyze in a bit more scientific way all the associated Risk factors that have been implicated in the development in non-union by um completing this study that you see here from my institution.
[2:41] And we identified
[2:43] 21 factors that have been implicated in the development of nonunion based on the level of the existing scientific evidence.
[2:56] So one can conclude that nonunion is a multifactorial.
[3:04] Post Fracture fixation complication.
[3:09] In terms of the pathogenesis of nonunion.
[3:13] Three theories have been
[3:16] Proposed by a number of um clinicians and scientists.
[3:24] The first theory.
[3:27] Speculates the uncontrolled behavior of immune cells.
[3:35] And here we've got production of uh pro-inflammatory cytokines in excess. We've got impairment of recruitment of mesenchyma stem cells.
[3:52] And we've got an imbalance in innate and or adapted immunity at the Fracture site.
[4:01] The second theory refers to the local or systemic deficiency of mesenchymal stem cells.
[4:12] And according to this proposed theory, we've got insufficient numbers of mesenchyal stem cells at the Fracture sites, insufficient production of bone morphogenetic proteins and Other growth factors, but also,
[4:30] You may have at the local environment, the excess production of bone morphogenetic protein inhibitors.
[4:41] The third theory.
[4:43] Speculates dysfunction of cells acting at the late stages of Fracture repair. So here we've got
[4:54] Insufficient vascular invasion.
[4:58] And also imbalance in metalloproteinases, which can have a negative overall impact on the evolution of Bone repair.
[5:13] What about now the diamond concepts and its relationship to Bone repair?
[5:21] First of all, I would like to um
[5:25] Remind everyone that
[5:29] Bone repair is a well orchestrated process.
[5:35] It restores the damaged bone in terms of its cellular composition, structure, and biomechanical function to its pre-injury stage.
[5:46] In essence, is a continuum of processes where we've got the involvement of complex cellular elements and signaling molecules.
[6:00] This is a very simplistic uh way to appreciate the evolution of uh Fracture healing. So, we move on from the, from the initial inflammatory states to a repair states and lastly to the remodeling state and as you can see, there is an overlap amongst these three.
[6:29] Unique processes.
[6:35] Overall, it is accepted today that Fracture healing consists of 5 stages.
[6:43] The hematoma stage, the inflammation, the angiogenesis, the cartilage formation, and the bone remodeling.
[6:51] And as I stated previously, is a continuum where we progress from one stage to another until completion of the overall bone healing process.
[7:06] In terms now of the Diamond Concept.
[7:10] I would like to.
[7:13] Uh, give credit to my co-authors about this conceptual framework of Bone repair, to Thomas Einhorn from Boston and to David March from London.
[7:24] And basically
[7:26] Uh, we are discussing about the lack of a common language for the understanding and treatment of the nonunion problem over a dinner one evening.
[7:40] And during that,
[7:44] Specific.
[7:46] Meeting
[7:48] We came up with these diamond concepts and our objective was to make communication easier and to increase the understanding of what is essential for a successful outcome amongst clinicians.
[8:07] So this is a simplistic.
[8:11] Um, appreciation of what does the Diamond Concept refer to. It refers to the minimal requirements that must be present at the Fracture site, at the nonunion site for a successful Bone repair outcome.
[8:33] So you must have present.
[8:37] Osteoprogenitor cells or else mesenchymal stem cells, you must have present an uh a matrix.
[8:46] A scaffold as we call it.
[8:50] A growth factor that will give the signal to the progenitor cell to undergo the process of mitogenesis and differentiation.
[9:00] But also you must have.
[9:03] Uh, adequate fixation of the Fracture of the non-union for, for the processes to evolve successfully from one phase to another, and this is what's called the mechanical environment.
[9:21] Moreover, it became clear that unless you've got good vascularity at the nonunion sites, then it will be a problem in terms of the function of the cells.
[9:36] Because you need to consider how the cells will get oxygen to continue to work, how they will get nutrients, and both the oxygen and nutrients are delivered to the nonunion site, but they are by the adequate, adequate blood supply by the presence of vascularity.
[9:57] You need also to consider in your treatment strategy, the host and the potential comorbidities of the host.
[10:07] So, in summary, the diamond conceptual framework represents an overview, a summary of the important parameters that must be present and what a surgeon must consider in his treatment strategy for a successful uh surgical outcome.
[10:36] Let's look now what is the role of diamond concepts in the treatment planning.
[10:43] This is a personal position statement, and I believe that each patient and nonunion carries different characteristics and challenges both for the patient and the surgeon.
[10:58] So, in your treatment strategy, you need to consider the damond conceptual framework of bone healing in order, in order to decide what component might be missing that you must include in your treatment strategy.
[11:17] So let's look into this case example.
[11:21] This is a 65 year old female who sustained a proximal femoral Fracture. She's a smoker and diabetic. These are the immediate postoperative X-rays and you can see how this Fracture was stabilized. Of course, uh, with hindsight, you can be critical about how this case was managed in terms of the fixation, in terms of opening the Fracture site.
[11:47] And the associate gap, the residual gap gap which is present at the Fracture site.
[11:54] There was no progress of healing activity after 6 months. The patient was referred to my clinic.
[12:02] Biochemical investigations to exclude low-grade infection were, they were all within normal limits. Clinically, the affected extremity was shortened by 1.5 centimeters, but there was no rotational deformity. The patient was in, uh, was suffering from Pain since the operation, unable to lay bear. She was still using crutches six months down the line.
[12:28] And she, when she walked into my office, she was in tears due to the poor quality of life, and she had mental illness as she was suffering from depression due to the functional restrictions that she was, she, she had to put up with during the past 6 months.
[12:51] So, trying to evaluate what is the problem here, it became clear that the mechanical component, according to the Diamond Concept was not adequate. The host did have comorbidities, being a smoker and diabetic.
[13:10] But also in terms of the biological component of the, of the, of the diamond conceptual framework, one can appreciate that there was a gap at the non-union sites and therefore, some form of biological stimulation failed to be appropriate and in this respect, the surgeon should consider what should be implanted at the non-union site.
[13:39] Mesenchy stem cells, a growth factor, a scaffold, or else all of the above.
[13:48] So these are intraoperative pictures. You can see that I went to the contralateral femur and I used the real device to get some autologous bone graft and in this case, this autologous bone graft represents um a, a scaffold which uh contains a bit of osteogenicity and osteoinductivity.
[14:14] However, because of the host and the gap, I decided also to uh um uh uh uh increase the cellularity of the rear graft by harvesting Bone Marrow aspirate from uh uh the left iliac crest.
[14:35] And therefore
[14:37] My biological um uh uh stimulation here to start with was based on the implantation of Rhea graft which was augmented with more progenitor cells.
[14:56] So after the harvesting of the real graft, I went to the affected uh non-union sites. The nail was removed and then when I opened the non-union sites to see how I can mobilize this um uh disrupted previous fragments, you can see how apart there were the two fragments together and all the scar tissue that had formed between.
[15:24] The different um fragments of the nonunion.
[15:28] So here, here are the original Fracture ages.
[15:32] And then I had to mobilize them as you can see with the osteotome.
[15:37] To try to reconstitute the femoral canal, to reconstitute the tube.
[15:44] This is the guide wire that was inserted and then after rimming, a new nail was implanted to again address the mechanical environment.
[15:57] So as you can see, uh, the incision of the nail here, fluoroscopic views, and then.
[16:05] We, we said previously that I harvested the Bone Marrow aspect. This is the Rhea graft, so I mixed uh the Rhea graft with the Bone Marrow aspect to give musclearity, but at the same time, after mobilization of uh the previous fragments, it became clear that, that, that was a very difficult case to put right and this is why, as you can see here, I decided also to use a growth factor.
[16:34] This is bone morphogenetic protein and also uh to augment the rear graft with another scaffold in order to increase the volume of my graft material.
[16:47] Here, as you can see, I mobilized the fragments.
[16:53] So that
[16:55] I can reconstitute the tube of the female, and I put here the collagen sponge of BMP2 around the fragments that I mobilized to put them around the nail so that I can shape again, the femur as it's supposed to be, and I use circular wire over the collagen sponge to maintain.
[17:19] These fragments around the femoral nail, as you can see here, that's my first kitchen wire. The second one, this is the BMP 2, putting it around my circular wire and around the, the fragments that I immobilized to reconstitute the tube, and then all this area.
[17:38] It was grafted with the rear graft which was loaded with progenitor cells and another scaffold which was used as a graft expander, expander, and you can see here how all this area was grafted. This is an intraoperative picture. These are the postoperative radiographs. You can see where was the previous nonunion and how I immobilized the fragments to reconstitute the tube.
[18:09] This is, this case, uh, 3 months down the line and you can see gradually that there is some healing activity. 6 months, there is more healing at least medially.
[18:22] As you can see, and by 8 months, there was also healing laterally, and you can see how we managed to, to heal this difficult nonunion after a period of 8 months by applying the diamond conceptual framework of Bone repair in this difficult case, in this difficult host.
[18:44] We reported the results of treatment in this publication from my unit, um, applying the Diamond Concept in 64 patients with difficult, uh, nonunions mean age of 45 years of age. You can see the distribution of, uh, humerus, radius, clavicle, femur, and tibia.
[19:06] The median number of previous interventions was 1, but ranged from 1 to 51 to 5, and overall.
[19:15] We had a success rate of 98.4% in this difficult cohort of long bone nonunions.
[19:25] Now let's move on.
[19:27] How oxygen can be used within the diamond conceptual framework of Bone repair in one's practice.
[19:38] So first of all, I would like to remind everyone that is listening that EXOGEN is a non-invasive biophysical stimulation. Basically it's an Ultrasound bone healing system, is, is FDA approved.
[19:54] Um, low-intensity pulse Ultrasound liPulse Technology to stimulate the bone healing process.
[20:03] It can easily penetrate the soft tissues to reach both deep and superficial fractures.
[20:10] These are the indications for um application for utilization of these bone stimulating device and it's not my intention to go through, through all of them but uh they can be found easily uh in uh in, in, in, in the website of Bio Vendors.
[20:33] In terms of the safety of estrogen, there are no known contraindications for its usage. Some patients may be sensitive to the Ultrasound gel, but uh uh the number of patients that they, they have reported a skin reaction is actually minimal.
[20:54] Uh, and in terms of safety and effectiveness,
[20:58] Um,
[21:00] You need to take into account that um uh you, you cannot use this device in immature patients, in pregnant or lactating women, in patients with pacemakers, poor circulation, blood clotting problems, or fractures linked to bone Cancer.
[21:22] But you can see the EXOGEN prescribing information for a complete list of warnings and precautions.
[21:31] So to summarize the action of this device, as I said, it is a noninvasive biophysical stimulation.
[21:41] It stimulates, it sends waves through the skin and soft tissues to the Fracture.
[21:48] It takes, uh, it, it induces activation of uh mechanoreceptors, the so-called integrins, initiating an intracellular cascade of events that, uh, leads to upregulation of um important genes and expression of proteins and growth factors which are critical to bone healing.
[22:15] So we've got activation of vasculoidoterial growth factor, the BMP2, uh, family, and we, that all this activation leads to differentiation of progenitor cells to osteoblasts which then can start the deposition of new bone where it's needed.
[22:36] But the oxygen also supports the mineralization process as it increases the bone mineral density and all that contributes to the Bone repair process.
[22:50] So one can say that the EXOGEN has a very important role to play within the Diamond Concept. It can be considered as an adjunct to biological stimulation.
[23:08] However, one must take into account that there is no mechanical instability, no deformity, no problems with soft tissues, and there is no underlying low-grade infection.
[23:26] Assuming therefore that there, there, there is nothing of these important factors, then one can safely use the oxygen device.
[23:40] Now, how can it be used in one's practice? It can be used as a biological stimulation to non-union prior to surgical intervention.
[23:53] So you can buy sometimes, uh, sometime in terms of when you want to intervene. Sometimes the patient does not want Surgery straight away, and this is a great opportunity to provide biological stimulation to the non-union sites and to um uh give the best chance for the non-union to progress to healing by stimulating the local progenitor cells.
[24:24] You can also consider the use of EXOGEN after surgical intervention where, where a delay is seen with no progress or signs of healing.
[24:41] So to conclude,
[24:44] I tried to give an overview about the problem of nonunion in terms of the Risk factors and its pathogenesis.
[24:54] A summary of uh what the Diamond Concept consists of and how one can use the diamond conceptual framework in his practice to treat patients.
[25:09] I share with you an example of a nonunion where the diamond configuration was applied based on the evaluation of what is the problem at the local environment.
[25:23] But also, I referred to how estrogen, this biophysical stimulation device, non-invasive device, can be considered and used within the diamond conceptual framework of Bone repair.
[25:42] In your practice.
[25:44] So to put all these together.
[25:48] The messages to take home are nonunion continues to be the most challenging complication to manage post Fracture fixation.
[25:57] The Diamond Concept represents a common language of communication amongst clinicians to remind them of the minimum and essential requirements of a successful healing response.
[26:11] The oxygen device.
[26:14] I can be considered as an important agent of biological stimulation.
[26:20] And it can be used as another treatment option within the Diamond framework of Bone repair.
[26:30] I hope
[26:32] You found useful my talk, and you can consider the diamond framework in your practice when you treat, when you manage difficult cases of nonunion. Thank you so much for listening.