Episode Transcript
[00:00:02] Speaker A: Welcome to your Cases on Hold, the JVGS podcast, hosted by Andrew Schoenfeld and Aisha Adkeen.
[00:00:08] Speaker B: Here we discuss the best of what each issue of JBJS has to offer with the usual dose of entertainment and pop culture.
[00:00:16] Speaker A: Take us with you in the gym, on the commute, and, as ever, whenever your case is on hold.
[00:00:27] Speaker B: Welcome back everyone, to your Case Is on hold, episode 102. If you are listening to this on the day we drop, you're raising a glass of green beer. Because this is St. Patrick's Day, March 17, and you are waiting eagerly for the March 18 issue of the Journal of Bone and Joint Surgery. We are covering the best in orthopedic research and everything that there is in this episode of JBGS this month. I'm Aisha Abdeen Arthroplasty Surgeon at Boston Medical center and Associate professor of Orthopedic Surgery at Boston University and and I have here with me I am Andrew
[00:01:00] Speaker A: Schoenfeld, professor of Orthopedic Surgery at Harvard Medical School and Vice Chair for Education and Department of Orthopedic Surgery, Mass General
[00:01:08] Speaker B: Brigham thank you for tuning into the podcast today, everyone. As always, our opinions are our own and not representative those of the Editorial board, the Editor in Chief, nor the constituent editors of jbjs. This episode of youf Cases on Hold is brought to you today by the Miller Review Course.
So let's get started. On the top of the pile we have what's New in Hand and Wrist Surgery by Wagner. There's a highlight and it's permanently free.
A Physician Led Health System in response to Dr. Devaluation Healthcare consolidation and Private Practice Endangerment the Commons Clinic Origin Story by Rankumar Broken but Not Invisible Identifying Human Trafficking in Victims with Orthopedic Injuries by Punts.
Precision in the Theater by Chen this one's Permanently Free Orthopedic Research in Singapore. The Past, Present and Future by Tan. And there's a highlight, AI in orthopedics the wisdom of should we versus can we insights from the 2025 AOA leadership poll by Murphy I'd like to draw your attention to a special edition in this issue.
It's an editorial entitled with gratitude to Dr. Thomas Einhorn, founding Editor of JVGS Reviews, Honoring a legacy of orthopedic and editorial leadership. This was penned by none other than JBGS editor in chief, Dr. M.O. bandari and Consultant Editor and former JBGS editor in chief Dr. Mark Swiantowski, who stayed over the past 13 years. Dr. Einhorn's dedication and vision have been instrumental to the growth of JBGS Reviews as a trusted source for expert insights into orthopedic research and clinical practice. In January, Dr. Einhorn stepped down as editor, passing the baton to Dr. Sanjeev Sabarwal.
Dr. Einhorn is an internationally recognized expert in adult hip and reconstruction surgery whose research has included the study of novel biologic techniques to treat joint ailments. He has authored more than 240 articles, contributed to multiple textbooks, and received several awards and recognitions. Among highlights of a notable career, the authors proceed to reflect on Dr. Einhorn's contributions to our field. In my current role as the Chief of the Division of Hip and Knee Arthroplasty at Boston Medical Center, I'm honored to be even peripherally exposed to Dr. Einhorn's legacy, where he practiced arthroplasty and was the Chair of the Department of Orthopedics at our institution for 18 years. His commitment to rigorous research and clinical excellence endures in our department.
While I came here after he had left for New York, I have had the pleasure of meeting him at our eponymous Einhorn Day Symposium, held annually in his honor, and have interacted him with as a reviewer and an author for JBJS reviews myself, I'm sure we speak for the orthopedic community as a whole when I say we are thankful to Dr. Einhorn for his founding of and contributions to JBGS reviews and for his graceful leadership as a distinguished clinician and surgeon scientist in our field.
[00:04:05] Speaker A: Yeah, definitely one of the leading lights and luminaries in the orthopedic space over the last 25 years. For sure.
[00:04:14] Speaker B: Absolutely.
Now for our headlines. Andrew is going to start us off with the lead article, which is free for 30 days by Louis and colleagues, entitled Go ahead Andrew.
[00:04:24] Speaker A: This is Subjective and Functional Dysphagia after Anterior Cervical Spine Surgery A Prospective Controlled Study this is research that, as in the title, is a prospective study where the investigators wanted to look at functional dysphagia and this is a common occurrence in the setting of anterior cervical spine surgery due to the dissection. The use of retractors can also of course happen just in the setting of intubation and use of the endotracheal tube.
In light of that, when they say it's a controlled study, their control group were similarly sized lumbar procedures just to have some type of contrast in similar spine surgical procedure where they're not manipulating the airway, esophagus, et cetera.
This study is motivated by the Premise that there are widely varying ranges of reported dysphagia following cervical spine procedures. They quote 1.7 to 71%. And obviously that, yeah, I mean, you can hardly be broader. That's going to be predicated on the type of surgery, the length of surgery, obviously the extent of dissection, and what they're trying to do in terms of affecting a decompression, fusion, corpectomy, et cetera. There's broad variation in type of surgeries that are performed. There's broad variation in the substrate that you're working on in terms of the patients and their baseline risk for dysphagia, which can be influenced on a number of different levels. This is a prospective study, so they had a very good implementation, which was that they were going to do swallowing function assessed at five time points preoperatively and then on postoperative day 0, 3, 7 and 30, using the validated Eat10 survey and the Yale survey swallow protocol.
So they, as you would expect in a prospective study, they're going to try and come up with, what's the sample size that we need here?
And so they said that they anticipated postoperative dysphagia of about 45% among cervical spine surgery patients. Based on prior literature, they need at least 30 patients with dysphagia at each time point, representing 67. Well, they would require at least 30 patients with dysphagIA at each time point, and therefore 67 patients would be needed. So that's a pretty superficial. And you do see this. I think this is a teaching point that extends beyond, you know, this spine surgery is not your thing. You don't care about dysphagia after cervical spine surgery. But. But you do see this quite regularly with prospective studies.
And they, they treat it almost like it's this randomized trial. So we're just going to power for an outcome, and if we do that, then everything else should take care of itself. Because it's a prospective study or powering on outcome.
In this study, you're really wanting to see the depth and breadth of cervical spine surgery experiences and then also address the confounding factors. Age, frailty, prior spine surgery or prior neck surgery.
BMI even can be postulated to affect issues with swallowing. So there's a lot of other factors that they're really not taking into account. They're just saying we're going to have 67 patients.
And while that, yes, may power you for the outcome of dysphagia, it's not powering for the intersection or interaction between the cervical spine procedure and, and these other factors that may play into proclivity for dysphagia.
So I think that's important to recognize. And again, because they're treating as a prospective study, they do this power calculation, they just do These unadjusted analyses, two sample T tests, specifically the Welch 2 sample T test chi square analyses, and then they use linear regression and that's to evaluate the adjusted association. So t, they're trying to do an adjusted analysis of swallowing scores with patient characteristics, operating room time and surgery type. So they have patient characteristics. That's not one single variable. That's multiple operating room time and surgery type.
So some other points here that I think are again, kind of more broad and teaching points for everyone who's trying to do research of this type, not necessarily specific to this, although of course relevant linear regression is for continuous data and continuous data that's normally distributed and continuous data that is not bounded at zero.
And I don't believe that the EAP 10 survey or the Yale Swallow protocol meet either one of those criteria.
Most of those kinds of scores are going to be bounded at zero. You don't get like negative scores, for example.
And as you can see from like later on in the data, when they talk about just the very large percentage of patients who have evidence of dysphagia at certain time points, it's non parametric. So that violates several assumptions for linear regression models. The problem being that if you deploy linear regression on an inappropriate substrate that violates the assumptions, you can get spurious results and conclusions.
So I think they would have been better off probably just doing their bivariate comparisons with the t test and the chi square test and leaving the regression analysis out of it. Especially since, as I already mentioned, they're not really capturing the variables that exist in the full universe in a sufficient number. They have 67 patients in each group. They have 134 patients total.
So again, they're not very specific on what factors they included. They're probably reasonably powered, if you will, to include those variables in a multivariable regression analysis. But again, they may have issues with restricted clinical variation or what we call clinical truncation across the spectrum of disease. And that's going to be a bigger factor in that setting. So what did they find? They found preoperative dysphasia was slightly more common in the cervical group than in the lumbar group, 11.9 versus 7.5%. So right at baseline, preoperative.
Again, I think that just speaks to everything I already mentioned. About risk factors at baseline and then post operatively, dysphagia significantly higher in the cervical group with prevalence at 70% on day zero and then kind of trending down all the way to 36% essentially at postoperative day 30, versus about 5% in the lumbar group. However, and this is a point that they mentioned in the results and then kind of, it just sort of doesn't come up elsewhere. On postoperative day 30, 1/3 of patients with earlier dysphagia in the cervical group had persistent symptoms, 1/3 had recovered and 1/3 were lost to follow up.
[00:11:50] Speaker B: Yeah, that sounds interesting.
[00:11:52] Speaker A: Yeah, that's a major, that's a major issue for a prospective study. When you've lost 33% of your patients, you can't even comment on what they're doing one month out.
[00:12:03] Speaker B: Yeah.
[00:12:05] Speaker A: So they talk about the eat 10 scores and they start doing these subgroup analyses about steroid exposure. But I would take those with a grain of salt because again, recognizing that they're missing a sizable proportion of the patients that are likely underpowered to account for those parameters. So they say our findings suggest that most cases are transient and self limited with only one third of patients still reporting symptoms at 30 days. And if you acknowledge that they're also missing a third of the patients at 30 days, I think that, you know, that that has to be contextualized when they, when they're making that claim. And then they say these findings support the characterization of dysphagia as a common self limited postoperative symptom rather than a true complication, which I thought was a little bit puzzling as kind of the. That conclusion features prominently in the abstract.
Of course, we always talk to patients about the prospect of dysphagia after cervical spine surgery, particularly anterior.
We certainly don't characterize it. I don't present it. I haven't heard others present it as a complication. It's sort of a. Yeah, it's an expected thing. Different people experience different ways. And here I think you can. From a natural history standpoint, this study adds value in presenting kind of that natural history. How long is it going to last? Help educate patients with some relatively high quality prospective study.
However, when we do say it's a complication, and I'm speaking now as a researcher, from a health services standpoint, we would generally say prolonged dysphagia is a complication.
And prolonged dysphagia was present in about 30% of these patients. It's not characterized beyond 30 days. Typically that's the kind of the cutoff for prolonged dysphagia. And prolonged dysphagia is considered a complication.
So I think some of this is they kind of went on a side quest, as the younger kids are saying these days, to try to combat like, oh, dysphagia, it's not a complication after surgery. Well, no one really said it was a complication early on, but once you start getting to where it's more of a prolonged thing, you can't say, no, no, no, that's not a complication with the data that they've put together, especially when they're creating a cutoff at 30 days and they're not exploring further. And they lost a third of their patients at 30 days.
[00:14:22] Speaker B: Yeah, that was a big concern about the patient loss. But also, you know, they report that there's no functional dysfunction, but if the patient has dysphagia, they're still going to be upset by that. It's still a complication, you know, one year out. They have that.
[00:14:35] Speaker A: Right.
[00:14:35] Speaker B: What were your thoughts on the steroid? I thought that was interesting that they said, you know, there was no difference in their result of dysphagia whether they were given steroids or not. But the obese patients tend to have been given more steroid, were more likely to receive steroids, so wouldn't that wash out the effect of steroid? If obese patients are at higher risk of getting dysphagia, more of them got steroid and then it was equal between the steroid and non steroid.
[00:14:58] Speaker A: Really good, you know, good detection on your, on your end. And I think that, you know, this just goes back to what I was saying about they don't have enough clinical variation in these different domains. So when they're saying, oh, the steroid, there's no benefit to steroid, I think they're underpowered to really investigate that. And then certainly when you start getting into the true interaction of BMI and this study is a prospective study, it's not controlling for selection and indication bias. And they could give steroid preferentially to whoever they wanted to.
I think that there was a misstep for them to try to even wander into that area. And again, you know, we've, we've talked about this, you and I, on previous episodes, but I think some of this, sometimes I can see that, like, that may have been a force. They were forced into it, they were strong armed into it by a reviewer who is like, I want more information on that front. You have to comment on this. And then they give it to them to get the paper across the finish line. And sometimes you do have to do that from a strategic gamesmanship standpoint. But I think if it was, it's an unforced error if, if it wasn't. If they weren't compelled to do that.
[00:16:08] Speaker B: Yeah, got it.
Let's move along.
I'll discuss the next paper by Dong and colleagues entitled Clinical Application of an Ultrasonic Bone Scalpel in the Treatment of Osteoid Osteoma A Single Center Pilot Study. This paper has a commentary and is permanently free.
In this single centered study there was a retrospective analysis was performed that included patients who were radiographically or histologically diagnosed with osteoid osteoma at Shanghai General Hospital from September 2022 to November 2023. Briefly, osteoid osteoma is a common benign bone tumor that affects children and adolescents with a higher incidence in males. It usually affects the appendicular skeleton and is associated with nocturnal pain, and the pain classically resolves with salicylic acid analogs on CT scan. Osteoastoma has a radiolucent nitus and a dense surrounding area of sclerosis.
There are four types of this lesion. There can be cortical, cancellous, subperiosteal, and intra articular based on location.
Surgical intervention for osteoid osteoma is typically associated with soft tissue trauma, difficulty locating the nidus and residual bone defects, and so the common treatment has emerged to be CT guided radiofrequency ablation or rfa, which is minimally invasive and effective. However, there are some limitations that the author's note for large nidus sizes or proximity to critical structures which may be damaged with rfa. The Ultrasonic Bone Scalpel or the UBS is a novel device that employs high frequency piezoelectric vibration to selectively cut bone while sparing adjacent soft tissue.
Due to its minimal bone tissue trauma and favorable safety profile, the UBS has been widely applied in delicate procedures involving the spine, joints and extremities. However, the application of this technique in the treatment of osteo osteoma has not been reported.
The authors here of the current studies hypothesize that the device's selective cutting capability makes it a promising option for managing osteoid osteoma, particularly in lesions for which RFA or surgery may be less effective, such as those with extensive sclerosis or proximity to neurovascular structures.
The treatment modalities in this retrospective study were either RFA or UBS or a combination of RFA and UBS Demographic data, clinical presentation, radiographic characteristics were collected and analyzed.
Treatment failure was defined as symptom recurrence, reoperation or the occurrence of complications.
A total of 77 patients were included. 60% of the lesions were in the femur and the mean nidus diameter was 11.58 millimeters plus or minus roughly 6 and there were 36% were cortical, 32% were cancellous, 25% were intra articular and 7% were subperiosteal lesions.
30% had RFA, 34% had UBS alone and 36% had both RFA and UBS.
Patients with a cortical or subperiosteal lesion exhibiting a prominent NIDUS and surrounding sclerosis were preferentially treated with navigation assisted UBS heritage and in contrast cancellous lesions with smaller nidus and less surrounding sclerosis, CT guided RFA was preferred in patients with an intra articular lesion recurrence after prior treatment, a NIDUS diameter of more than 1cm or prolonged disease duration. A combination of CT guided UBS curettage and RFA approach was adopted to ensure complete nidus removal and symptom resolution.
Follow up was conducted via an outpatient visit and telephone interviews. Post op CT or MRI were used to confirm complete removal or ablation of the NIDUS and pain status was assessed using a visual analog scale for pain on post op day three and at one month.
Gait recovery was evaluated monthly through telephone interviews which is interesting and the time to normal gait was recorded.
For patients returning for follow up, CT or MRI was used to evaluate changes in the surrounding sclerotic bone and the resolution of bone marrow edema.
Treatment failure was described again as recurrence reoperation recurrence. Of the complications of the 77 analyzed patients, 83% presented with a primary lesion and 17 had a recurrent disease case characterized by persistent pain.
All patients successfully underwent the assigned surgical procedure.
They document their operative time and as well they report at 66 months, 71% 71 patients, rather 92% underwent MRI follow up revealing evident resolution of the bone marrow edema and of joint effusion and at 12 months repeat MRI for 59 patients or 77% of them showed near complete resolution of edema and further improvement of joint effusion. At the time of final follow up. No patients reported recurrence of pain or other symptoms related to osteo osteoma.
Thirteen of the patients whose index surgery was a revision, nine of them previously underwent open surgery and four had undergone minimally invasive procedures and they described recurrence in six patients was attributed to inaccurate identification of the nidus location. And all of those patients, those six were treated with the use of UBS at their second operation, which was the index operation for this study inclusion.
The authors report there was success in 97% of the entire cohort. They report that in 91% of the RFA group alone there was success and in 100% of the UBS or the UBS combined group there was 100% success, essentially.
And they say that three days post procedure, two patients in the RFA group or 3% of the whole cohort had recurrent pain and then were treated with secondary UBS surgery. I thought this was somewhat aggressive because without any further imaging, just ongoing pain at three days post op, and typically you can expect some pain to be present at three days post op. But they on spec went in and did the UBS procedure in those three patients that still had pain at that time frame. So also the inclusion of recurrent cases does add to the heterogeneity of this of the cohort, I would have suggested leaving out all the recurrent cases to analyze specifically the UBS plus RFA and the RFA alone.
And also it's a little unclear because it was retrospective. They sort of defined their guidelines as when they used combined UBS and rfa, but it seems as though that might have been overkill if they get 100% of clearance with the UBS alone. So again questioning why the use of both of them combined.
But the authors conclude that this is a very reliable and effective way to treat osteoid osteoma. And they recommend combining UBS and RFA for cases that are intra articular and have a NIDUS of more than 1cm.
It wasn't described which cases did have anitis based on the size of 1cm or over for the threshold and if all of them underwent rfa.
That's an interesting conclusion, but it does make sense that the more complex ones would be treated with this. I do wonder if they're underplaying the invasiveness of this procedure because it is considerably more invasive than the rfa.
But they did note paradoxically that RFA patients had higher pain and a delayed return of gait function, which is also interesting for me. This remains somewhat on hold, but I'm interested in hearing your thoughts, Andrew.
[00:23:32] Speaker A: Well, I mean there's, I think the points that you made are all valid for someone who's looking to apply this to their own practice. The points to Emphasize from, from my standpoint reading this were one, it's a rote clinical retrospective of the author's experience.
So selection, indication, expertise bias, all baked in.
And their approach to. They convey their approach to using this, but they're not comparing their approach to how they manage these to any other kind of approach. So it's 77 patients, which in the context of osteooma may be a reasonable sample, of course, but at the same time it's not a super large cohort. There's a lot of heterogeneity, as you already emphasized. And I don't like putting, I don't like it when they put outcome rates or percentages without context. So they say treatment success was 97%. Okay, but what there's a 95% confidence interval around that and that's going to be predicated on the total number of patients you had, individuals at risk, so on and so forth. They should have at least provided that nothing is never and nothing is always. So when they're saying we have no major complications. Well, if you did this in 7,000 patients, you know, there may be a few even just due to chance. So this isn't really giving you the full clinical picture about what could happen with these types of, of treatment protocols. And again, even just some being happening just due to chance.
So I think it's, you know, it's an interesting study. It's a reasonable number of patients. I don't think that there's necessarily. You should accept that there's a broad generalizable capacity to it. Also there are statements at the end that, you know this.
The recommended treatment algorithm supports clinical decision making and each treatment approach has its own advantages. It is recommended to select a surgical method on the basis of the lesion characteristics. That's not based on the research they did. Those are general best practice points for any kind of surgery.
[00:25:33] Speaker B: Exactly.
[00:25:34] Speaker A: So those are just pretty.
You want to avoid non sequiturs in the conclusions. I think.
[00:25:41] Speaker B: Agree.
The next paper is our your case is on hold featurette entitled Impact of the femoral pin tracker on soft tissue tension in Robotic assisted Total knee arthroplasty. A prospective randomized control trial.
This study is by on and associates and essentially the authors sought to determine whether intra articular versus extra articular placement of the femoral pins in robotic total knee arthroplasty had an impact on soft tissue tension within the joint.
A total of 132 patients undergoing robotic assisted total knee arthroplasty were prospectively enrolled.
Of those, 80 were randomized to receive an intra incisional or extra incisional femoral pin tracker during surgery. Soft tissue tension in the medial and lateral compartments of the knee was measured using a sensor before and after removal of the pin tracker. Measurements were performed at 10 degrees, 45 degrees, 90 degrees and 120 degrees of flexion. Changes in knee joint soft tissue tension before and after removal of the pin tracker were compared between the two groups.
The authors performed a pilot study to determine the power calculation and 80 patients were included.
Their findings were that after the pin tracker was removed, the tension in the medial compartment of the intra incisional group was greater than those of the extra incisional group when the angle knee flexion was 10 degrees and that difference was 32.43 Newtons versus 6.21 Newtons.
This change was also apparent at 45 degrees of flexion and 90 degrees of flexion but not at 120 degrees of flexion. The changes in the medial compartment were different at those degrees of flexion at 10 degrees, 4590 degrees but not at 120 degrees.
The tension changes in the lateral compartment by comparison did not differ between the two groups at any angle and no difference was observed in the length of the main incision between the two groups.
No pin related complications were observed in either group.
So the authors conclude that the tension of the joint can change if the pin placement is within the incision.
I would contend that when we look at the technique, the pin placement was within 1.5 cm of the medial epicondyle of the femur and that is within the zone of the origin of the MCL and therefore that does make sense that it could distort the tensioning within the medial compartment and it is possible to place an intra incisional pin more proximally that is still within the incision but not in that zone of the origin of the mcl.
Additionally, there are other things that can create additional tension within the joint. It would have been interesting if the authors had included variations in alignment with varus deformity. There's significant tighter MCL and this may have changed the results as well.
Conversely, valgus knees have a lax MCL and it would have been interesting to see if there were differences based on alignment. Furthermore, BMI and adipose tissue can also play a role in applying tension on the pin trackers and potentially could distort the joint. So it would be interesting to have a subgroup analysis of different BMI as well as alignment of the knee. But overall I think it's A very important finding. It is helpful to know that the soft tissue can be distorted, particularly on the medial side, when placing intra incisional pins during robotic surgery. And I think it would change care to make sure that really is cautious of staying away from that zone of where the MCL originates when placing these pin trackers, regardless of whether they're going intra or extra incisional. The benefit, of course, of going intra incisional is potentially reducing the incidence of infections. However, in this group, they did not have any complications in either group. I'd be interested to hear your thoughts, Andrew.
[00:29:54] Speaker A: Yeah, I mean, as far as like the RCT aspects of the study go, I think it was, you know, well done, well planned. A few questions that I had, you know, they go through the power analysis. They say based on their estimations they needed 28 patients, but then they go to 40. Now normally you see like there's a 10 adjustment for patients who are lost to follow up and things like that. Even a 20 adjustment, you're just talking about adding like maybe 10 to 12 patients, not, you know, you are aiming for essentially 30. And they, they were like, we're going to enroll 80. So I wasn't clear around the purposes for that. Even with that.
Some of the points that you're bringing up are just going to get at the clinical variation issues, problems with restricted clinical variation and truncation in that regard. And those are always very hard to account for effectively in randomized studies just because of the number of patients that you would really need, as it's a randomized study that was adequately powered and they checked all the boxes.
One of my pet peeves, if you will. At the end they say it was a single center study with two surgeons. Okay, that part is fine. If you're just working with two surgeons, you're working within what those two surgeons do. And there could be an expertise component to that. So they say future multicenter studies with larger samples are needed.
I don't know that this really needs to be replicated in a multi center setting based on their findings.
And certainly you don't need larger samples because you were adequately powered. Based on. You are more than adequately powered, actually.
So that seems to be like some boilerplate language and falls into the dude and Brandt paradigm where we get to.
No, don't, don't say that. Don't say more studies. If you're doing a randomized study that's adequately powered and you checked all the boxes, don't then say, well, more studies are needed and we need larger samples. Because that probably isn't true. That's the whole point of doing an adequately powered rct. And then they say the sample size was small, although the power analysis indicated that was sufficient for the primary outcome. Well, then the sample size wasn't small. The sample size was adequate. Again, more than adequate, actually.
You went well above and beyond without even what is expected. You went beyond what is expected without an explanation.
So some of their limitations don't seem especially well contextualized. And. And for this kind of study, I would say we have the answer here.
More research is not needed. Larger studies are probably not required.
[00:32:27] Speaker B: Yep, 100%. It's almost like that needs to be a statement that people feel the need to add at the end of a study. We should do this next. But sometimes cases close, right? We've figured it out and we can move on.
[00:32:37] Speaker A: That's right. We need to advance the science, not just keep living in a. We'll replicate, replicate, replicate.
[00:32:45] Speaker B: Agree.
Okay, wait, wait, wait.
[00:32:48] Speaker A: And then also, this study did come with a comment visual summary, and it's 30 days free, so you don't need to take it from us listeners. You can figure it out for yourself.
[00:32:58] Speaker B: Excellent. Good point. Thank you, Andrew.
Okay, so we will move on to our honorable mentions.
This study is the trapezius aponeurosis insertion on the acromion. And it's an anatomical study with a possible.
With a possible implication for a dynamic stabilization of the acromioclavicular joint by Sigura and associates.
This was a purely cadaveric assessment. The background is that they were looking at the trapezius as a dynamic stabilizer of the AC joint.
The function has drawn attention to the treatment of AC joint dislocation.
The study aimed to clarify anatomy of the age aponeurosis of the trapezial insertion of the AC joint. Their hypothesis was that the trapezius aponeurosis would exhibit distinctive characteristics in three separate regions, the acromial, the AC joint and the clavicular insertions.
They analyzed 21 cadaveric shoulder specimens from 13 donors of Japanese ethnicity. There were four male and nine female.
The 15 specimens were analyzed macroscopically and five were histologically examined. One specimen was excluded because of osteoarthritis. Macroscopic examination included aponeurosis length measurement and fiber orientation analysis.
They found that the trapezius aponeurosis inserted on the medial edge of the acromion, the posterior end of the AC joint and the posterior edge of a lateral clavicle. The mean aponeurosis length was longest at the acromial insertion followed by the AC joint insertion, and the shortest was at the clavicular insertion.
The trabezius aponeurosis was found to extend to the surface of the acromion and the AC joint, connecting these structures to the deltoid origin.
They also found with the histological observation that the aponeurosis was inserted via fibrocartilage only at the acromial insertion and just posterior to the AC joint. The aponeurosis at the AC joint insertion was thicker than that at the clavicular insertion. This is very interesting because it's emerging as we didn't really know, that the trabezius aponeurosis was such a major stabilizer potentially of the AC joint.
The authors conclude that the Trabecius aponeurosis at the acromial and AC joint insertions form a contiguous complex with the origin of the deltoid and with the superior AC joint, and that this is clinically relevant because just posterior to the AC joint may be a critical dynamic stabilizer of the joint to be focused on when we have dislocations of the AC joint.
Okay, so there you have it. That's the lineup for March 18th. Thank you for your attention.
[00:35:38] Speaker A: That study did come with a comment and is also permanently free, so people can check that out at any time at no charge.
[00:35:46] Speaker B: Okay, thanks Andrew. Sorry I missed that.
[00:35:50] Speaker A: No worries.
This was great. If you can share the podcast rate, give us a five star rating. We're on Casto, Stitcher, Amazon, Spotify. If you can't find us in any of those places, just go to the JBGS website and please like and subscribe and tune in for the next one.
[00:36:12] Speaker B: Thanks everybody.
