Listen to Tim Coughlin and Tom Kurien discuss the paper 'Mechanisms of pain in knee osteoarthritis that influence outcomes after total knee arthroplasty surgery' followed by a summary of the August Round-ups.
Paper discussed:
Mechanisms of pain in knee osteoarthritis that influence outcomes after total knee arthroplasty surgery
Listen to Tim Coughlin and Tom Kurien discuss the paper 'Mechanisms of pain in knee osteoarthritis that influence outcomes after total knee arthroplasty surgery' followed by a summary of the August Round-ups.
Paper discussed:
Mechanisms of pain in knee osteoarthritis that influence outcomes after total knee arthroplasty surgery
[00:00:00] Welcome to this month's Bone & Joint 360 podcast. I'm Tim Coughlin and we've got the roundup of the roundups edition today. We're going to start off with an interview from our feature article, author, Tom Kurien, before we move on to our roundup.
And I'm here with Tom Kurien, who is currently the Exeter knee reconstruction unit fellow, and the first author on this month's feature article Mechanisms of pain in knee osteoarthritis that influence outcomes after total knee arthroplasty.
So welcome, Tom. This was a really interesting paper to read with some new concepts that I'm sure quite a number of our listeners won't be familiar with. So firstly, what causes pain in knee osteoarthritis?
Thank you, Tim. So pain is a complex multifactorial subjective unpleasant experience, which we all know encompasses many things. Obviously is influenced by memories, emotions, pathological states, and genetics and cognitive factors. [00:01:00] And we know that arthritis is a painful condition, many patients complaining in our clinic of arthritis, pain, and many pharmacological treatments don't really help, but there are many reasons why patients have pain. And I think, not just the structural damage, including osteophyte synovitis, bone marrow edema, and periosteum, but there were many other genetic factors and things maybe as orthopaedic surgeons, we haven't really considered, especially these sort of psychological aspects, including anxiety, depression, and catastrophize. And so I think these are things we need to really investigate further as orthopedic surgeons.
Yeah, that's very interesting. So why do patients have such a range of experience pain? Which seems relatively decoupled through radiological appearances?
Okay. So osteoarthritis, we know it is very painful, but there is a significant discordance between radiological and clinical symptoms. And why that is, I think because pain is a very subjective experience. Patients report pain on a [00:02:00] visual scale, zero to 10. People rate their pain very differently. And I think people cope with their pain very differently. I think these are one of the main things and actually I think a clinician can't go guarantee just on radiological symptoms, radiological evidence as to how bad their pain is.
And I think, I think two things as well, interestingly, we've been working more and more on imaging. And I know X-rays have been our traditional standard in orthopedics, but using other modalities like MRI, we've actually picked up other pathological structures and many are painful, including the side of bone marrow edema which has been increasingly more explored as reasons of pain and arthritis, which you're not seeing on conventional radiographs.
So I think that's really interesting cause you mentioned the synovitis and that's often a word we hear associated with inflammatory arthritis. And traditionally we thought of osteoarthritis as a degenerative process. But it does seem, it's actually got an inflammatory component as well. Is that right?
That's true. So I think that the two things, two new concepts, so we always thought that [00:03:00] osteoarthritis is noted,sensitive pain condition. What I mean by that, it's like, we always thought it was a structural disease involving the tissue. So the bone is damaged. The nerves get activated, and you get pain. So that's what we always think. But actually about 34% of patients with knee osteoarthritis have some common neuropathic component of pain. And when we are talking neuropathic component is actually potentially an inflammatory component and this can either be in the periphery of the joints or in the central nervous system. And this inflammatory component actually causes significant pain. And actually we've been shown recently that the synovitis in the knee, which is an inflammatory condition can generate many cytokines and neurofilaments that can cause pain and then result in this inflammatory nature of pain. And it very much summarises this neuropathic component. So actually as orthopaedic surgeons, yes, we do see people with swollen knees and inflammation, and maybe many of them are managed by the rheumatologists, but the inflammatory nature of osteoarthritis is increasingly more research [00:04:00] now. And I think this is something we need to be aware of.
That's really interesting. Now, one of the things that you mentioned a lot in your paper is bone marrow lesions, which isn't something that certainly 10 or 20 years ago we were talking much about. So what are those and what effect do they seem to have on pain?
Yeah. So bone marrow lesions are only seen on MRI scan. These are not seen on traditional radiographs and the official definition of sort of non-cystic subchondral bone areas, which have ill-defined high signal intensity, which are adjacent to cartilage, but can only be seen on a T2 weighted MRI scan. Now increasingly they're made up of sort of fatty tissue and sclerotic to but they are, there's been recent work showing that there's significant crosstalk between the subchondral bone marrow edema and the college degeneration underneath that. So actually these are maybe prearthritic changes seen on an MRI scan, which result in progression of arthritis. So that's why patients with radiological x-rays when you sort of say, well, I didn't have mom. They had a very mild [00:05:00] osteoarthritis in that compartment. For the MRI scan they have significant bone marrow edema. So it means that that components in the threat, and actually there's a reason for that pain as well.
Now, these changes have on average, these bone marrow lesions have been highly associated with pain and multiple studies in the US have shown that they've been associated with pain and they wax away, they increase in size and then decrease in size. And the change in size is associated with that pain people experience as well.
There is work being shared on using zoledronic acid, which is, you know, we know effects bone remodeling as these are associated with osteoclast turnover. And we do know that osteoclasts are highly associated with pain as well because they activate something called the trippy one pathway. And this bone remodeling you see with bone marrow lesions may be an like a biomarker for osteoarthritis, and potentially if we treat people potentially with zoledronic acid or bisphosphonate treatment in the future, this may be something we can treat patients with for significant bone marrow edema and pain.
But one thing [00:06:00] we've done recently and obviously we've looked at a sort of nerve fiber activation and we found the nerve, there are actual nerve fibers in bone marrow lesions. So potentially this opens up a new avenue of treatment cause subchondroplasty has been introduced in sort of my arthritic arthritis, orthopaedic world, essentially injecting cement into these bone marrow edema, potentially that may burn off the nerve fibers and potentially prevent the progression of arthritis. So I think more work has to be done on that in the future, but it's actually quite exciting.
I mean, that's really interesting. And it's important to say that these are a totally different entity to the, to the bone cysts that we often talk about as part of arthritis and see on x-ray.
Yeah. Bone cysts are very different. So bone cysts, I think are a late complication of sort of cartilage degradation. You get sort of cliffs within the cartilage where synovial fluid tracks down into a subchondral bone, forming a sort of cleft and then a cyst and these are also very painful but these are very different. And these bone marrow edema, you do see in arthritic patients, but you do see also in sort of traumatic injuries as well. Like ACL, you sort [00:07:00] of get the pivot shift bone bruising on MRI scan. And these are the same kind of characteristic changes you see in osteoarthritis as well.
That's really interesting. Now, could you just tell us a little bit about a temporal summation of pain and conditioned pain modulation?
Yep. These are probably relatively new concepts with maybe the orthopaedic audience, but these are both terms used to assess called central sensitization. Now, just in very brief terms, central sensitization is a phenomenon where sort of the whole body is sort of resulting in pain to amplification of pain signals from the spinal cord, very much similar to sort of a fibromyalgia kind of picture. So patients described generalized body pain, even though sort of their knee arthritis is the main stimulus.
Now temporal summation and conditioned pain modulation are two methods of assessing the central sensitization. Now in very simple terms, if I have a neurofilament and press it on your knee you probably think it's slightly sharper, maybe slightly painful and to a normal person, you probably say [00:08:00] rating of sort of one out of 10, but if you stimulate that area 10 times, and then you ask the patient what would be the pain for that 10th stimulus people that essentially sensitize would probably say it's 10 out of 10, whereas a person with no arthritis, no evidence of census sensitization would probably say, it's say one out of 10. So its exaggerated pain response to repeated stimuli is something called temporal summation. And this is a valid measurement of central sensitization. And you can do this at the bedside. Potentially we could use this in the future to paint phenotype patients and look at their outcomes after surgery. And there has been work done by a Danish group we've worked with showing that this simple test at the bedside can predict chronic pain after knee replacement. So I think more works needs to be done on this, but actually it's a very exciting avenue to explore.
And the other term you mentioned is conditioned pain modulation. Now the simple way of explaining this is it's your body's descending pathways. So if you bang your elbow on a door, you rub it. And actually by [00:09:00] doing it, you are actually rubbing the skin over the injured area by doing so it sends signals from the brain to numb the pain down. And that's why when a child falls over and you rub on their shin, by doing that it sort of distracts them, but also it stimulates their descending and actually numbs their pain down and they obviously get soothed. Now, patients with osteoarthritis for a chronic period of time, they lose the descending inhibition. So this ascending signals from the knee to the brain are increasing, but the body's coping strategy is dysregulated therefore they can't reduce the pain signals from their knee downwards. Like the gate control theory, the gates open and the flood signals of pain are going up, but there's nothing to stop them. So that is essentially addition pay modulation. And there are ways of measuring this now at the bedside. What we can show is that patients who have facilitated temporal summation and conditioned pain modulation preoperatively are at higher risk of getting chronic pain and being dissatisfied after knee replacement.
It's all fascinating stuff. So what do you [00:10:00] think the next step is then?
Well, I think, I think, yeah, especially the need need community to be, there's been a big movement on, on revisions and managing revisions and and know Andy Thompson and the guy's dog sort of done a really good job on this.
And I think pain is one of the main problems that we all suffer with in terms of managing our patients. And I think potentially we need to set up sort of pain paintings really in, in our, in our elective service. So we can actually screen patients preoperatively who enlisting for surgery and potentially identify those that may do badly after an outcome after knee replacement.
Now, many of our patients with knee osteoarthritis do have quite significant pain and their radiographic changes of osteoarthritis. And what we do know is that even with the knee replacement, when they actually are better than me work, but they may report disatisfaction. And that can be quite disappointing, especially those with our NGR figures and trying to make sure that we choose winners. But I think what the key thing is actually these kind of tools will actually help us give individualized medical, give an individualized medical approach to patients potentially using [00:11:00] pharmacological treatments, behavioral therapy and, and a combination of sort of treatments with sort of psychologists and maybe an anaesthetist as well to actually improve the patient, improve the outcome for our patients who undergo knee replacement. And I think this approach which I don't think will take too much just needs a facilitated team and a network to build on. I think, I think, I think we're in the right place to do that now to the UK.
That's fascinating. So what would be your take home message then for the surgeons listening, who are currently performing total knee replacement?
So, I wouldn't want to change that practice sort of thing, but I think, I think essentially, I think one of the key things we might see in the future which pain phenotyping patients were listing for knee replacement surgery, maybe a really important step. Now, simple things like questionnaires and simple plans. There's some of these, these tests I've described today, we can be done at the bedside and may be introduced in big trials here in the UK, and then looking at longer term outcomes after knee replacement may actually improve our outcomes after surgery here in the UK, and our NGR figures. And these [00:12:00] simple methods of actually probably referring patients to the appropriate teams, pay management, psychology, behavioral therapy may actually improve everything for our patients with knee osteoarthritis and outcomes after surgery.
That was fascinating stuff. Thank you very much for your time, Tom.
So starting with hip and pelvis, our first paper from Australia looks at the issue of periprosthetic hip fractures. Specifically, it's concerned with fractures involving a loose stem and adequate bone stock, a B2 fracture on the Vancouver classification.
The current orthodoxy is in favor of revision in this group of patients. However, there is increasing use of open reduction, internal fixation as a primary treatment. The study was a meta-analysis of 24 studies comparing RF to revision. The 24 studies included 1,621 patients, 331 of whom underwent RF and the rest revision. Primary outcome was complications of any kind.
[00:13:00] The overall complication rate was 24% for RF and 18% for revision, which was not significant. RF had a lower rate of dislocation than revision and no significant difference was found in any other complication. Whilst this is only level three evidence it may be that RF should be considered in more of these cases.
Our second paper from the United States is a double-blind randomized control trial, comparing intraarticular steroid and ketolorac for the management of pain from osteoarthritis. Whilst intraarticular steroid has been shown to be effective for this indication there were also known issues, namely, the systemic effects of steroid injection and basic science evidence of chondro toxicity and a potential increased risk of infection in subsequent joint arthoplasty. 110 patients with hip or knee arthritis were randomized and outcomes were recorded at one week, one month and three months.
Both groups demonstrated a significant improvement in pain, which [00:14:00] was greatest at one week. And there was no difference between the groups at any timepoint. While insets have their own potential side effects, it is useful to know that there is level one evidence for ketolorac as a safe and effective alternative.
The final Hip paper comes from the United Kingdom and is an embedded study within the National Joint Registry, including over 20,000 each of hip and knee arthroplasty patients.
This interesting paper looks at the trajectory for pain and function over time, based on Oxford hip and knee scores. All operations were performed in the years from 2009 to 2010. Schools were available at six months and then one, three and five years post-operatively using regression analysis. Two trajectories of recovery were identified.
70% of patients were classified as level one responders who had a sustained high level of improvement throughout. The remainder were [00:15:00] classified as level two responders who also improved, but at a lower level. Those with worse outcomes at six months were more likely to follow a level two response.
This paper is a very clinically relevant paper for practicing surgeons and healthcare policymakers alike. As outcomes continue to be publicly available and there is greater and greater push for improved outcomes for the majority of procedures, understanding recovery and the predictors of recovery is increasingly important.
Moving on to our Knee Roundup. Our first knee paper is from Australia and it looks at whether a number of commonly used medications are associated with progression of knee osteoarthritis. A baseline cohort of 2,000 patients with Kellgren Lawrence grade two or more arthritis with annual follow-up data for eight years were identified.
Data were analyzed with a random effects to aggression model. The most frequently used medication families were [00:16:00] statins in 27%, anti-hypertensives in 15%, nonsteroidal antiinflammatories in 15% psychological medications in 14%, anti-histamines in 10%, osteoporosis interventions at around 11% and diabetes medications at 7%.
The headline finding of this paper was that current use of nonsteroidal antiinflammatories when compared to the control group was the only medication associated with their loss of medial joint space width. Clearly this proves only association and not causation. It may give cause to consider how and when to use onsets in osteoarthritis, but it would be our opinion at BJ360 that it does not provide evidence of a rationale not to provide these drugs when deemed necessary.
The second knee paper comes from the Bristol group in the United Kingdom. It is another embedded National Joint registry study looking at more than [00:17:00] 33,000 revision knee arthroplasties. Methodology is high quality and establishes the cumulative probability of revision and subsequent revisions following primary knee arthoplasty. The essence of this article is that revision rates were higher in males than females by 10 years, that's 20% versus 14.8%. And that being younger was also protective.
Overall, nearly 20% of first revisions had undergone a second revision by 13 years. The outcomes were remarkedly poor for these second revisions where 21% had been revised again within five years. And 20% of these were revised again within three years.
This paper demonstrates quite dramatically the effect of survivorship of the first, second, and third revision operations. In other words, when it goes wrong the first time, it is more likely to go wrong again. The study also demonstrates that younger patients, especially [00:18:00] men undergoing revision surgery have the poorest survivorship. And that second revision is a slippery slope with markedly shorter intervals. This is sober reading for arthoplasty surgeons performing surgery on younger people with longer and longer life expectancies.
Our final paper also comes from the United Kingdom and is also using National Joint Registry data. The authors used the results of 764,888 primary total hip arthoplasties undertaken by 3213 surgeons and 889,954 primary knee arthoplasties undertaken by 3,084 surgeons. These operations were performed over a 10-year period.
In terms of outlier status, approximately three and a half percent of surgeons were potential revision outliers for hip or knee arthroplasty.
This study found that surgeons who use more than one [00:19:00] type of implant in their practice are more likely to have outlier status on the National Joint Registry. While the association was not huge, it was per implant. So though you are choosing many types of implants appeared increased and cumulative risk of failure.
For knee arthoplasty each additional implant gave an increased odds ratio of 1.35 and for hip arthroplasties it was 1.12. Clearly there are multiple risk factors at play, but it seems sensible to take note that use of fewer implants may be a modifiable risk factor. Now moving on to our sports roundup.
The first sports paper comes from the United States and it looks at the chronically controversial topic of arthroscopic partial meniscectomy in the knee. Most would agree arthroscopic debridement in the presence of significant osteoarthritis is not of benefit whereas if the patient suffers mechanical symptoms, [00:20:00] many would advocate for the surgery.
This paper presents a case areas of 565 consecutive patients undergoing arthroscopy for a range of symptoms and pathologists. The main patient age was approaching 50. Using multivariate regression models adjusting for confounders it was demonstrated that significantly worse patient-reported knee symptoms were strongly associated with tricompartmental cartilage damage, but not at all with meniscal pathology.
The paper supports the idea that arthroscopic debridement of presumed mechanical symptoms in the setting of cartilage damage is unlikely to benefit the patient as the pain is associated with the cartilage injury, rather than the meniscal pathology. However, in younger patients with isolated meniscal pathology, there may still be a role for arthroscopic debridement.
Our next sports paper comes from France, and this looks at treatment after first time shoulder [00:21:00] dislocations. Everyone agrees that there is a high rate of secondary dislocation in younger patients and that consideration should be given to stabilization after a first event. Consensus ends on this point, however, as no one can agree on what is a young patient, what role non-operative management has and in whom it should be used.
This small randomized control trial of 40 patients between 18 and 25 years of age randomized participants to arthroscopic Bankart repair within two weeks of injury or nonoperative management after a first dislocation. Therapy in both groups was matched.
The primary outcome was recurrent instability and secondary outcomes were range of movement, return to sport and patient-reported outcome measures. Mean age was 21 and 83% of participants were male. Recurrent instability was significantly lower in the operative group with [00:22:00] 10% versus 70% for those treated nonoperatively. Patient-reported outcomes at two years favoured the operative group and 89% of those treated surgically reported equal or better level of sports participation compared to 53% in the nonoperative group. Accepting this as a small study, it certainly informs the conversation in clinic with patients in this position.
Now moving on to our foot and ankle Roundup. While most large joints have arthoplasty options for arthritis, the tibiatalar joint has been later coming to the party. Arthroplasty is however gradually replacing arthrodesis as the primary treatment.
Our first paper from the United Kingdom reports on five-year followup of 114 patients receiving a third generation total ankle replacement with an ultra-high molecular weight polyethylene bearing and a calcium phosphate spray over the cementless surface to enhance RCO [00:23:00] integration. Overall, 15% of patients required an additional procedure with subtaler fusion, being the commonest followed by Achilles tendon lengthening.
Complications were reported in 47% of cases, but were mostly minor. Malleolar fracture and wound healing issues were the commonist. There were no cases of deep infection in this series. 89% of patients were satisfied with surgery and a similar number would recommend it to a friend. Visual analogue scale pain scores fell from seven out of 10 preoperatively to three out of 10 postoperatively.
10 ankles in total required revision leaving an 88% survival at seven years. This paper adds weight to the fact that arthoplasty is becoming the gold-standard replacing arthrodesis for ankle arthritis.
Our second paper from the United States follows on from the first and asks how long it takes to get the maximum [00:24:00] benefit after total ankle arthropathy.
This was a systematic review, which identified studies, including patients with a total ankle arthroplasty in which patient-reported outcome measures were analyzed at six months, one year and two years following surgery. Overall, there were 12 studies that met the inclusion criteria reporting the outcomes of 1,514 patients with an average duration of 2.3 years.
The mean age of the patients were 61. Males were more common than females accounting for 55% of the cohort. As expected post-traumatic arthritis was the commonest indication for total ankle arthroplasty in this younger cohort. In the seven studies reporting complications and overall rate of 8.5% was seen, including six cases of revision total ankle arthroplasty, and 23 cases of reoperation.
In terms of functional outcomes, the American Orthopedic Foot and [00:25:00] Ankle society, Hind foot score and visual analogue scale pain scores demonstrated clinically significant improvements that exceeded the minimum clinically important difference at six months postoperatively. But interestingly not thereafter.
Patients also reported significant improvements in the short musculoskeletal function assessment dysfunction and sub scores up to one year postoperatively, but not thereafter. These results suggest that patients report significant benefit within the first six months of surgery, and may continue to experience further improvement up to a year, but no further improvement after this point was shown.
This information can be useful in counseling patients seen postoperatively in terms of determining how much further they can be assumed to progress in that first year. Our final paper comes from Brazil and looks at insufficiency fractures of the foot and ankle in post-menopausal women. [00:26:00] This was a case control study of 55 patients with fractures who were matched to a control group of 51 with a mean age of 64.
Steroid use was seen in 20, out of 55 patients in the fracture group and overwhelming majority of 89% had a metatarsal fracture, most commonly involving the fifth metatarsal. There was no difference in vitamin D level or body mass index between the cases and control groups, but steroid use was significantly more frequent in the case group.
In all, 52% in the control group are diagnosed with osteopenia and 27% were diagnosed with osteoporosis. In the control group, 43% had osteopenia and only 10% had osteoporosis. Statistical analysis suggested that steroid use was not significantly associated with the development of the insufficiency fractures, but vitamin D level and lumber bone marrow density status.
The radiological parameters of [00:27:00] calcaneal pitch and metatarsus adductus angles were also found to be significantly associated with the risk of development of insufficiency fractures. The study indicates that low bone mineral density and unfavorable biomechanical factors such as Kivas foot and metatarsus adductus were associated with a higher risk of insufficiency fractures of the foot and ankle.
Now, moving on to our wrist and hand roundup. Our first hand paper comes from the United Kingdom and looks at the nonoperative management of bony mallet injuries. Over a four year period, 211 patients presenting with 218 bony mallet injuries were treated nonoperatively with a custom thermoplastic splint.
These patients were assessed with functional outcome measures and patient-reported outcome measures. Overall, there were no differences in the patient-reported outcome as assessed by the patient evaluation measure at a mean of 327 days [00:28:00] post-injury, regardless of injury classification, joint, subluxation, or size of articular fragment.
Interestingly, there were also no differences in the objective clinical measures, a distal interphalangeal joint, including flection, extension regardless or extension leg of articular subluxation. There were small observed differences and extenser lag when comparing those patients with preexisting degenerate changes on plain radiographs and the size of the articular fragments.
The overall complication rate was low with superficial skin irritation and temporary Swan necking, each observed in 12 fingers. But there are no clinically, no statistically significant differences in both subjective and objective functional measures, regardless of joint congruence is an important finding, which demonstrates the safety and predictability of non-surgical management in these common injuries.
Our second hand paper comes [00:29:00] from Brazil and asks if local corticosteroid or night orthosis is more effective nonoperative treatment for carpal tunnel syndrome. 100 patients were randomized to each intervention with primary outcomes of improvement in nocturnal paresthesias symptoms and Boston Levine questionnaire score. All patients were documented as at least moderate severity or nerve conduction studies.
Corticosteroid injections were superior to orthosis in remission of nocturnal parasthesia with remission rates seen at one month being 84% versus 44% respectively. At three months being 71% versus 40. And at six months being 80% versus 30%.
Only a minority of patients at baseline had nocturnal parasthesia, including 35% in the corticosteroid group and 42% in the orthosis group. Therefore it is bizarre to describe the absence of nocturnal parasthesia,in the patient who did [00:30:00] not have these symptoms at baseline as a remission.
There were around double the numbers of severe carpal tunnel syndrome in the orthosis group, which are 19% versus the corticosteroid group, which were 10 percent. These aspects of the trial may explain why the results contrast with those of the instincts trial, a larger multicenter study from the United Kingdom, which demonstrated no difference between orthosis and injection at six months. However, it is nonetheless interesting that in this cohort of patients with relatively severe disease that outcomes were generally superior with corticosteroid injection versus all orthosis.
Now we move on to our shoulder and elbow roundup. Our first shoulder and elbow paper from the Netherlands seeks to answer what we should do with the isolated Mason two displaced partial articular radial head fracture. 45 patients were randomized to open reduction and screw fixation or nonoperative management with a pressure [00:31:00] bandage.
Clinical outcomes and patient-reported outcome measures were assessed at admission and subsequently at three, six and 12 months.
Mean dash score, Oxford Elbow score and Mayo Elbow Performance score all at post-operative follow-up points were similar with the dash scores at 12 months being a median of zero in the operative group compared with 1.7 in the nonoperative. Range of motion and pain, visual analogue scores also showed no difference between the groups at any of the time point.
At 12 months, the proportion of patients scoring excellent or good on the Mayo elbow performance score was 96% in the operative group and 91% in the nonoperative group. At present provided there is not rock to forearm rotation. And in the absence of better powered studies, this work would seem to support a non-surgical approach.
Our second paper from the United Kingdom looks at the [00:32:00] surgically tricky problem of gaining reliable fixation in ununited lateral clavicle fractures. This was a retrospective review with 38 patients with a mean age of 46 with nonunion defined as a lack of radiological union associated with pain or loss of function at a minimum of three months post injury.
Patients were treated using a combined lateral clavicle locking plate with a tunneled suspensory fixation consisting of braided non-absorbable suture through the coracoid clavicle and plate secured by a button on each side. All fractures were radiologically united by six months following surgery. Two patients required metalwork removal for hardware permanent.
The data provided are reassuring in demonstrating the effectiveness of this treatment for patients presenting with lateral clavicle nonunion and it shows that for this cohort of patients treated initially nonoperatively the results of delayed surgical management can be [00:33:00] excellent in terms of patient-reported outcome range of movement and pain scores.
This leads us into our trauma round up. Our first trauma paper asks if routine MRI is required to identify a Colt femoral neck fractures in the presence of an ipsilateral femoral shaft fracture. The work is from South Korea and evaluated 79 patients with high-energy femoral shaft fractures, 13 of whom were found to have an acult neck fracture.
They specifically looked for the presence and predictive capability of a capture sign, which is measured on an axial soft tissue window of a CT of the pelvis. The capsular thickness was measured as the distance to the anterior capsule from a line drawn from the intertrochanteric crest to the anterior femoral head.
The thickness difference between the two sides was evaluated in the occult fracture and non fracture cohort, and any difference beyond one millimeter was considered to be a positive sign. [00:34:00] The study found near perfect agreement for the capsular sign in detecting an occult fracture, picking up 12 of the 13 patients.
For these true positive occult fracture patients, the thickness difference was approximately four millimeters and all patients had a lipo hemarthrosis visible on the CT as either a fat fluid level or a fat globule in the non-fracture group, four patients had a positive capsular sign. For these false positive patients the thickness difference was two millimeters with no patient having a light hermathrosis. The findings of this study, show that the capsular sign together with the presence of a llight hermathrosis is an excellent predictor of an occult femoral neck fracture.
There was one false negative and say the possibility of a femoral neck fracture still exists despite a normal capsular sign. In cases with high suspicion and a negative CT a MRI may still be required. However, a careful [00:35:00] examination of the CT scan may reveal most fractures and obviate the need for further imaging.
Our second trauma paper from China asks if the practice of sending baseline cultures from the initial debridement of open fractures gives useful information. On the one hand, there is the argument that initial baseline samples from the contaminated tissue at the time of initial surgery must offer the best idea of what bacteria are present and help with targeted antibiotics in terms of treatment and prophylaxis, if required. The counter-argument is of course that these samples do not take into account the antibiotic prophylaxis that is administered on admission. And as such, the samples may give a poor idea of what is likely to colonize any subsequent infected wound.
The study looked at 61 patients who developed infection after open fracture, all of whom had baseline cultures, as well as cultures after a subsequent infection developed. [00:36:00] At baseline, there was a relatively low rate of positive bacterial cultures of around 23%. This is not entirely surprising as the cultures are notoriously inseitive. Perhaps more surprisingly bacteria cultured after debridement bore little resemblance to those cultured after wound infection. And the overall concordance rate was only 3.3%. This is a valuable paper showing that it is more important to treat multi-drug resistant gram-negative bacteria as overwhelmingly the causative bacteria in deep infection. Not those detected immediately after debridement in infection after open fracture.
Our final paper from Canada looks at the effect of pre-existing oral anticoagulant use in patients with a hip fracture. Time to surgery after hip fractures in the elderly is widely accepted as a key determinant for improved outcomes.
Within this group of patients, there is one [00:37:00] cohort who are not receiving timely surgery and therefore potentially missing out on its benefit. This is the group of patients who are taking pre-injury oral anticoagulants, where there is no clear protocol of how to balance the risks of bleeding with the risks of delaying surgery.
The authors designed a systematic review and meta-analysis that included 34 studies reporting on the outcomes of over 39,000 patients comparing both time to surgery and in-hospital mortality between those on oral anticoagulants and those who were not. They identified that there was a longer time to surgery in patients receiving pre-injury or what oral anticoagulants with three fold, higher odds of not receiving surgery within 48 hours for the anticoagulated group compared to those not only anticoagulated pre-injury. They also calculated that the in-hospital mortality was statistically significantly higher in hip fracture, patients who received oral anticoagulants pre-injury.
[00:38:00] Further research is needed to guide the optimization of care pathways for hip fracture patients who receive these drugs, balancing the risk of bleeding during surgery with the risks of delaying the surgery. Moving on to oncology, our oncology paper this month comes from Germany and compares core needle and incisional biopsy in the diagnosis of musculoskeletal sarcomas.
While the decision-making surrounding who performs the biopsy is widely accepted, there is still considerable discrepancy between centres and surgeons as to how the biopsies are performed. Data from a cohort of 417 patients with a definitive diagnosis of bone or soft tissue sarcoma in whom 472 biopsies had been carried out as part of the diagnostic process were analysed.
The rate of unequivocal sarcoma diagnosis was found to be similar with both techniques in [00:39:00] terms of tumour grading for both soft tissue and bone sarcomas. However, there was a difference between the two techniques in terms of the number of repeat biopsies required following core needle biopsy. These were required when histological results were inconclusive and this was significantly higher 50 cases versus 5.
If surgeons consider the risks of incisional biopsy and the ease with which needle boxes can be arranged in treating units and the reduced risk of contamination outside the zone of excision, then it seems to us here at Bone & Joint 360, that the less invasive option is suitable in the majority of cases, assuming the surgical team are happy to repeat biopsies more frequently without too many apparent disadvantages.
And finally, we come to our Children's Roundup. Our first children's paper comes from the United Kingdom and it looks at the management of [00:40:00] completely displaced distal radius fractures. This common injury has traditionally been treated with a manipulation under anesthesia and often K-wire stabilization. The question is, is this necessary?
In this study 56 patients were offered either standard management or treatment with a straight plaster. 60 patients elected to go for the straight plaster with 37 choosing K-wire stabilization. All patients treated with a straight plaster were discharged before one year with a normal range of motion and radiological evidence of remodeling. For those treated with 17 patients had secondary displacement of over 10 degrees from the initial images.
Of these patients, nine had restricted range of movement, four of whom required physiotherapy. This paper provides clear support for treatment with a straight cast, and we await the results of the children's radius, acute [00:41:00] fracture fixation, or Kraft trial with interest.
And finally, sticking with paediatric trauma our last paper looks at the long-term outcomes and complications in adolescent mid-shaft clavicle fracture. In this paper from Norway 109 children between the ages of 12 and 18 with a displaced mid-shaft clavicle fracture were retrospectively reviewed with functional outcomes scores. 61 were treated nonoperatively and 48 were treated surgically.
The operative group was split evenly between open reduction and internal fixation and intramedullary nailing. There were no differences on the primary outcome measure, the quick dash, between the operative and nonoperative groups. So far say predictable. However, one of the common arguments advanced the operative intervention is to improve cosmesis. In this study the non-operative group was more satisfied with the cosmetic result. [00:42:00] The good long-term functional results of non-operative treatment suggest no additional benefit of surgery. And while cosmesis is often an argument advanced to support operative intervention here, as in our experience, patients preferred the absence of a scar.
I hope you've enjoyed this month's podcast and look out for our next one coming up in the next few weeks.