WEBVTT 00:00:00.000 --> 00:00:03.500 Imagine facing a persistent infection after shoulder 00:00:03.500 --> 00:00:07.120 replacement surgery. Well, it's a surgeon's nightmare, 00:00:07.160 --> 00:00:09.519 isn't it? And a patient's ongoing struggle. Absolutely. 00:00:09.679 --> 00:00:12.460 But one treatment approach, this two -stage revision 00:00:12.460 --> 00:00:15.880 with antibiotic spacers, it's shown really remarkable 00:00:15.880 --> 00:00:19.160 success rates. I mean, as high as 95 % in getting 00:00:19.160 --> 00:00:21.399 that infection under control. That's right. The 00:00:21.399 --> 00:00:23.699 control rates can be very good. Yet, as often 00:00:23.699 --> 00:00:26.079 happens in complex surgery, getting rid of the 00:00:26.079 --> 00:00:28.260 infection, that's really only part of the story. 00:00:28.399 --> 00:00:30.440 Does it restore function? What are the costs? 00:00:30.539 --> 00:00:32.719 The complications? Exactly. Function is key. 00:00:32.939 --> 00:00:35.280 And that's what this deep dive is all about, 00:00:35.619 --> 00:00:38.520 unpacking that complexity. Welcome to the deep 00:00:38.520 --> 00:00:40.700 dive, the show where we take your sources, the 00:00:40.700 --> 00:00:42.979 latest research papers, essential articles, even 00:00:42.979 --> 00:00:45.740 your own detailed notes, and extract the most 00:00:45.740 --> 00:00:48.820 important nuggets of knowledge or insight. Think 00:00:48.820 --> 00:00:51.399 of it as your shortcut to being truly well informed 00:00:51.399 --> 00:00:54.280 on a critical topic. Today, we're diving deep 00:00:54.280 --> 00:00:57.140 into a significant research paper focusing on 00:00:57.140 --> 00:00:59.920 treating infected shoulder prostheses using precisely 00:00:59.920 --> 00:01:02.579 that two -stage revision approach. And who better 00:01:02.579 --> 00:01:04.359 to guide us through this material than one of 00:01:04.359 --> 00:01:06.659 the authors of the paper itself? We're joined 00:01:06.659 --> 00:01:09.739 today by Professor Mo Imam, an orthopedic expert 00:01:09.739 --> 00:01:12.379 with an extensive publication record. He brings, 00:01:12.379 --> 00:01:14.459 well, unparalleled insight directly from the 00:01:14.459 --> 00:01:16.140 source. It's brilliant to have you here. Thank 00:01:16.140 --> 00:01:17.760 you. It's a pleasure to be here and discuss the 00:01:17.760 --> 00:01:19.900 work. Great. Let's jump straight in then with 00:01:19.900 --> 00:01:21.959 a rapid -fire setup to frame our conversation. 00:01:22.140 --> 00:01:24.739 First question. Shoulder periprosthetic joint 00:01:24.739 --> 00:01:28.379 infection, PJI. Why is this particular type of 00:01:28.379 --> 00:01:31.040 infection often considered, well, more challenging 00:01:31.040 --> 00:01:34.019 to treat than PJIs in, say, the knee or hip? 00:01:34.260 --> 00:01:37.219 Yes, that's a critical starting point. Shoulder 00:01:37.219 --> 00:01:39.719 PJI, it really does present some unique difficulties. 00:01:40.219 --> 00:01:43.640 A major factor is the microbiology. So alongside 00:01:43.640 --> 00:01:45.700 more common organisms like coagulus negative 00:01:45.700 --> 00:01:49.480 staphylococci, we frequently encounter propionobacterium 00:01:49.480 --> 00:01:52.040 agnes. or P. acnes, as it's often called now, 00:01:52.299 --> 00:01:54.840 cutie -bacterium axes. Now, while it's often 00:01:54.840 --> 00:01:57.180 less virulent than, say, Staphylococcus aureus, 00:01:57.200 --> 00:01:59.640 which you see more often in knee and hip PJIs, 00:02:00.280 --> 00:02:03.439 P. acnes can be notoriously subtle in its presentation. 00:02:04.340 --> 00:02:07.659 Sometimes pain is the primary or even the only 00:02:07.659 --> 00:02:10.020 symptom. The only symptom. That must make diagnosis 00:02:10.020 --> 00:02:12.419 quite elusive. It does. You can't always rely 00:02:12.419 --> 00:02:14.900 on those classic signs of infection. And then, 00:02:15.039 --> 00:02:17.539 both P. acnes and other organisms, they readily 00:02:17.539 --> 00:02:20.439 form biofilms on the implant surface. This protective 00:02:20.439 --> 00:02:22.939 layer, it sort of shields the bacteria from antibiotics, 00:02:23.360 --> 00:02:25.240 making them incredibly persistent, difficult 00:02:25.240 --> 00:02:27.419 to eradicate without surgery, and crucially, 00:02:27.740 --> 00:02:30.500 local antibiotic delivery. Subtle presentation 00:02:30.500 --> 00:02:33.120 and stubborn biofilms understood. Okay, second 00:02:33.120 --> 00:02:35.379 rapid question. The paper focuses on a two -stage 00:02:35.379 --> 00:02:37.780 revision using antibiotic spacers. In brief, 00:02:38.000 --> 00:02:40.050 what does that process actually entail? Well, 00:02:40.050 --> 00:02:42.030 it's essentially a sequence. It's designed to 00:02:42.030 --> 00:02:44.110 eradicate the infection before re -implanting 00:02:44.110 --> 00:02:47.229 a new prosthesis. So stage one involves removing 00:02:47.229 --> 00:02:50.050 the infected implant completely, meticulously 00:02:50.050 --> 00:02:52.370 cleaning out all the infected tissue that's the 00:02:52.370 --> 00:02:54.889 debridement, and then inserting a temporary cement 00:02:54.889 --> 00:02:57.689 spacer. A spacer. Yes, and the spacer acts as 00:02:57.689 --> 00:03:00.129 a local depot. It eludes high concentrations 00:03:00.129 --> 00:03:02.409 of antibiotics directly into the infected site. 00:03:02.889 --> 00:03:04.750 And of course, systemic antibiotics are given 00:03:04.750 --> 00:03:08.849 as well. And stage two. What happens then? Stage 00:03:08.849 --> 00:03:10.909 two is performed once we believe the infection 00:03:10.909 --> 00:03:13.169 is cleared and the patient has completed their 00:03:13.169 --> 00:03:15.770 course of antibiotics. It involves removing that 00:03:15.770 --> 00:03:18.569 temporary spacer and then implanting a new definitive 00:03:18.569 --> 00:03:21.449 prosthesis. The goal really is to put a sterile 00:03:21.449 --> 00:03:24.050 implant into what is now hopefully a sterile 00:03:24.050 --> 00:03:26.949 environment. Two distinct stages then aimed at 00:03:26.949 --> 00:03:29.849 clearing the infection first. Right. Final rapid 00:03:29.849 --> 00:03:32.169 -fire question. What was the single most important 00:03:32.169 --> 00:03:34.050 finding from this specific research regarding 00:03:34.050 --> 00:03:36.259 the control of the infection itself? I'd say 00:03:36.259 --> 00:03:38.479 the headline result from this particular series 00:03:38.479 --> 00:03:41.620 is the high rate of infection control we achieved 00:03:41.620 --> 00:03:45.060 with this two -stage approach. We saw successful 00:03:45.060 --> 00:03:48.560 eradication in 36 out of the 38 patients available 00:03:48.560 --> 00:03:52.099 for the final analysis. 36 out of 38, which translates 00:03:52.099 --> 00:03:55.259 to an impressive 95 percent success rate based 00:03:55.259 --> 00:03:57.639 on the defined criteria we use. Ninety five percent 00:03:57.639 --> 00:04:00.219 infection control. That's a really powerful statistic. 00:04:00.280 --> 00:04:03.120 But how do you get there and what's the full 00:04:03.120 --> 00:04:06.620 picture beyond just eradicating the bug? Let's 00:04:06.620 --> 00:04:09.099 dive deeper into the process, the challenges 00:04:09.099 --> 00:04:11.960 and importantly, the patient outcomes in this 00:04:11.960 --> 00:04:14.360 core segment. Let's do that. So diving deeper 00:04:14.360 --> 00:04:16.519 into that challenge you mentioned earlier, the 00:04:16.519 --> 00:04:18.439 source material makes it quite clear that shoulder 00:04:18.439 --> 00:04:21.439 PGI is Well, it's feared by surgeons. It is, 00:04:21.560 --> 00:04:23.519 yes. You highlighted the common organisms found 00:04:23.519 --> 00:04:26.480 in this study. Coagulase negative, Staphylococci, 00:04:26.480 --> 00:04:30.139 that was 42%, and P. acnes at 33%. That's correct. 00:04:30.459 --> 00:04:32.920 And that point about P. acnes being less virulent, 00:04:32.980 --> 00:04:35.500 but often causing only pain for clinicians listening, 00:04:35.879 --> 00:04:38.199 that sounds like a crucial diagnostic trap to 00:04:38.199 --> 00:04:40.439 avoid, doesn't it? Absolutely. It really is. 00:04:40.439 --> 00:04:42.980 You simply cannot wait for the typical signs 00:04:42.980 --> 00:04:46.560 of sepsis or acute inflammation sometimes. Persistent, 00:04:46.680 --> 00:04:50.019 unexplained pain in a prosthetic shoulder. must 00:04:50.019 --> 00:04:53.519 raise suspicion for a low -grade infection, particularly 00:04:53.519 --> 00:04:57.240 P. acnes. And then, as we discussed, the biofilm 00:04:57.240 --> 00:05:00.040 protects these bacteria, making surgical intervention 00:05:00.040 --> 00:05:02.980 almost always necessary for eradication. You 00:05:02.980 --> 00:05:05.040 can't just rely on antibiotics alone, usually. 00:05:05.240 --> 00:05:07.560 And the two -stage strategy is built specifically 00:05:07.560 --> 00:05:10.339 to address that biofilm and the persistent infection. 00:05:10.649 --> 00:05:12.689 Tell us a bit more about stage one as it was 00:05:12.689 --> 00:05:14.829 actually performed in the study. You removed 00:05:14.829 --> 00:05:17.550 the prosthesis, did the debridement, and implanted 00:05:17.550 --> 00:05:20.449 that handmade cement spacer loaded with gentamicin 00:05:20.449 --> 00:05:23.329 and vancomycin. What was the post -operative 00:05:23.329 --> 00:05:25.790 antibiotic regimen like? OK, so the protocol 00:05:25.790 --> 00:05:28.050 involved two weeks of intravenous antibiotic 00:05:28.050 --> 00:05:30.189 therapy initially. This was often adjusted based 00:05:30.189 --> 00:05:32.550 on the culture results once the specific organism 00:05:32.550 --> 00:05:35.250 was identified. Kalared therapy. Yes. And this 00:05:35.250 --> 00:05:37.370 IV course was followed by a pretty substantial 00:05:37.370 --> 00:05:39.310 course of oral antibiotics, typically lasting 00:05:39.310 --> 00:05:41.990 for 10 weeks. So the combination approach local 00:05:41.990 --> 00:05:44.829 delivery from the spacer and a prolonged systemic 00:05:44.829 --> 00:05:47.790 course. Ten weeks oral after two weeks four. 00:05:48.269 --> 00:05:50.089 That's quite a commitment for the patient. It 00:05:50.089 --> 00:05:52.750 is indeed. Compliance is obviously key. Then 00:05:52.750 --> 00:05:55.269 stage two, the re -implantation. The paper notes 00:05:55.269 --> 00:05:57.829 that reverse total shoulder arthroplasty, or 00:05:57.829 --> 00:06:02.079 TSA, was the default for most patients. 26 cases, 00:06:02.300 --> 00:06:05.019 I think? That's right, 26. But hemiathroplasty, 00:06:05.060 --> 00:06:09.339 HA, was used as a sort of salvage option for 00:06:09.339 --> 00:06:11.899 severe glenoid bone loss in a smaller number, 00:06:12.120 --> 00:06:15.000 eight cases. All right. And quite significantly, 00:06:15.439 --> 00:06:17.639 14 patients didn't actually proceed to stage 00:06:17.639 --> 00:06:20.379 two at all. They retained the spacer permanently. 00:06:20.920 --> 00:06:24.129 Why was that? Well, the decision for the definitive 00:06:24.129 --> 00:06:26.250 implant, or indeed whether to implant one at 00:06:26.250 --> 00:06:28.870 all, was dictated by several factors. Things 00:06:28.870 --> 00:06:30.850 like the extent of bone loss, particularly on 00:06:30.850 --> 00:06:33.310 the glenoid side, which can be severely compromised 00:06:33.310 --> 00:06:35.610 after infection, and the spacer implantation 00:06:35.610 --> 00:06:38.430 itself. Right, the socket side. Exactly. And 00:06:38.430 --> 00:06:40.569 also the patient's overall medical fitness or 00:06:40.569 --> 00:06:42.649 sometimes their willingness or lack thereof for 00:06:42.649 --> 00:06:45.350 further major surgery. RTSA generally offers 00:06:45.350 --> 00:06:47.829 better function in many scenarios, but it simply 00:06:47.829 --> 00:06:50.069 isn't possible without adequate bone stock to 00:06:50.069 --> 00:06:53.560 support it. HA and retaining the spacer were 00:06:53.560 --> 00:06:55.980 fallback options for the most difficult situations 00:06:55.980 --> 00:06:59.439 or less fit patients. Essentially, yes. HA for 00:06:59.439 --> 00:07:01.720 severe bone loss where RTSA wasn't feasible. 00:07:02.360 --> 00:07:05.040 And retaining the spacer for those unable or 00:07:05.040 --> 00:07:07.689 unwilling to undergo the second stage. And the 00:07:07.689 --> 00:07:10.490 study population itself, 48 patients treated 00:07:10.490 --> 00:07:13.850 initially, 38 available for analysis at a minimum 00:07:13.850 --> 00:07:16.730 of 24 months follow -up. It's mentioned that 00:07:16.730 --> 00:07:19.250 40 of the 48 were referrals from elsewhere for 00:07:19.250 --> 00:07:21.389 PJI treatment. That tells us something, doesn't 00:07:21.389 --> 00:07:23.709 it? These were likely already complex established 00:07:23.709 --> 00:07:26.310 infections. Indeed. That's a very important point. 00:07:26.810 --> 00:07:29.129 These were challenging cases, often patients 00:07:29.129 --> 00:07:31.870 who had undergone previous surgeries. They weren't 00:07:31.870 --> 00:07:35.089 typically primary PJIs presenting early and otherwise 00:07:35.089 --> 00:07:38.009 healthy patients. They were often tertiary referrals. 00:07:38.370 --> 00:07:41.129 Which makes the 95 % infection control rate perhaps 00:07:41.129 --> 00:07:43.310 even more impressive. Well, it certainly highlights 00:07:43.310 --> 00:07:45.410 the effectiveness of the approach in a difficult 00:07:45.410 --> 00:07:48.750 cohort. How did you rigorously define and confirm 00:07:48.750 --> 00:07:51.029 infection control in this study? What was the 00:07:51.029 --> 00:07:54.230 diagnostic process involved? OK, so infection 00:07:54.230 --> 00:07:57.370 control was defined by the absence of the recognized 00:07:57.370 --> 00:08:01.720 musculoskeletal infection society. the MSIS criteria 00:08:01.720 --> 00:08:04.699 for PGI at the final follow -up point. The standard 00:08:04.699 --> 00:08:07.680 criteria. Yes. And the diagnosis itself relied 00:08:07.680 --> 00:08:10.259 heavily on careful microbiological workup during 00:08:10.259 --> 00:08:12.639 the surgeries. This involved taking multiple 00:08:12.639 --> 00:08:15.339 tissue samples. We stipulated a minimum of three 00:08:15.339 --> 00:08:17.899 and culturing them on different media, both anaerobic 00:08:17.899 --> 00:08:21.079 and aerobic, and crucially incubating them for 00:08:21.079 --> 00:08:24.660 at least 10 days. Ah, the 10 -day incubation 00:08:24.660 --> 00:08:26.800 period again. That seems like a really vital 00:08:26.800 --> 00:08:29.240 nugget of information for anyone in a lab or 00:08:29.240 --> 00:08:31.759 clinic dealing with suspected shoulder PGI, doesn't 00:08:31.759 --> 00:08:34.679 it? Especially for P. acnes. It is absolutely 00:08:34.679 --> 00:08:36.799 critical. We can't stress that enough. Shorter 00:08:36.799 --> 00:08:39.100 incubation times, say the standard five or seven 00:08:39.100 --> 00:08:41.679 days, risk missing these low -growing organisms 00:08:41.679 --> 00:08:43.940 like P. acnes. And if you miss it. If you don't 00:08:43.940 --> 00:08:46.019 identify the pathogen, you can't target the antibiotic 00:08:46.019 --> 00:08:48.379 therapy effectively. It compromises your chances 00:08:48.379 --> 00:08:51.179 of eradication. So yes, extended culture time 00:08:51.179 --> 00:08:53.720 is non -negotiable for a thorough diagnosis in 00:08:53.720 --> 00:08:56.980 this specific setting. Makes perfect sense. And 00:08:56.980 --> 00:08:59.220 as you mentioned, despite all these careful steps, 00:08:59.440 --> 00:09:02.539 the headline result was 95 % infection control 00:09:02.539 --> 00:09:06.539 in 36 out of 38 patients analyzed. Remarkable 00:09:06.539 --> 00:09:09.470 success for such a difficult problem. What happened 00:09:09.470 --> 00:09:12.049 in the two cases where control wasn't ultimately 00:09:12.049 --> 00:09:14.169 achieved? Yes, it's important to look at the 00:09:14.169 --> 00:09:16.750 failures too. In one case, it was a persistent 00:09:16.750 --> 00:09:19.769 P. acnes infection after the re -implantation 00:09:19.769 --> 00:09:22.529 stage. This was in an older patient with a history 00:09:22.529 --> 00:09:25.690 of steroid use, which can be a risk factor. The 00:09:25.690 --> 00:09:28.090 other failure was a persistent coagulase negative 00:09:28.090 --> 00:09:31.129 staphylococcus infection, also after re -implantation. 00:09:31.490 --> 00:09:34.370 In both instances, the patients experienced ongoing 00:09:34.370 --> 00:09:37.009 pain, but unfortunately declined further surgical 00:09:37.009 --> 00:09:39.169 intervention. Right, and that's another factor, 00:09:39.210 --> 00:09:41.669 isn't it, in managing these complex cases, patient 00:09:41.669 --> 00:09:43.509 choice, and their tolerance for surgical risk, 00:09:43.570 --> 00:09:46.090 especially after multiple procedures? Precisely. 00:09:46.269 --> 00:09:48.429 High success rate, but not absolutely guaranteed, 00:09:48.549 --> 00:09:50.509 and patient factors certainly play a significant 00:09:50.509 --> 00:09:53.049 role in the final outcome. Okay, so infection 00:09:53.049 --> 00:09:55.750 control is paramount, and the results look good 00:09:55.750 --> 00:09:58.830 there. But functional recovery is often the patient's 00:09:58.830 --> 00:10:01.870 main priority, isn't it? How did the study actually 00:10:01.870 --> 00:10:04.070 measure how well patients' shoulders were working 00:10:04.070 --> 00:10:06.950 and feeling after all this treatment? We use 00:10:06.950 --> 00:10:10.629 standard validated scoring systems, primarily 00:10:10.629 --> 00:10:13.450 the constant Murley score and also the relative 00:10:13.450 --> 00:10:15.710 constant score, which adjusts for age and gender, 00:10:16.129 --> 00:10:18.909 making comparisons a bit fairer. We also use 00:10:18.909 --> 00:10:21.850 the subjective shoulder value SSV, where the 00:10:21.850 --> 00:10:24.210 patient rates their shoulder function themselves 00:10:24.210 --> 00:10:27.210 on a percentage scale from 0 to 100. And of course, 00:10:27.440 --> 00:10:29.379 the pain score, which is part of the constant 00:10:29.379 --> 00:10:31.259 assessment. And when were these measured? These 00:10:31.259 --> 00:10:33.480 were measured before the first stage, so baseline 00:10:33.480 --> 00:10:36.019 pretreatment, and then again at the latest follow 00:10:36.019 --> 00:10:38.440 -up point. That was either after the second stage 00:10:38.440 --> 00:10:41.200 re -implantation or, for those who didn't have 00:10:41.200 --> 00:10:43.960 a second stage, after the spacer implantation 00:10:43.960 --> 00:10:46.419 when follow -up concluded. Right. Looking at 00:10:46.419 --> 00:10:48.500 all patients treated with spacers, regardless 00:10:48.500 --> 00:10:51.000 of the final step, what did the overall group's 00:10:51.000 --> 00:10:53.059 functional outcome show? Was there improvement? 00:10:53.460 --> 00:10:56.399 Yes. For the entire cohort treated with the spacer 00:10:56.399 --> 00:11:00.299 protocol. So lumping everyone together initially, 00:11:00.679 --> 00:11:02.820 there was this statistically significant improvement 00:11:02.820 --> 00:11:05.659 in the overall constant scores, the relative 00:11:05.659 --> 00:11:08.100 constant scores, the subjective shoulder value, 00:11:08.480 --> 00:11:10.919 and importantly in their pain scores compared 00:11:10.919 --> 00:11:13.179 to their pre -treatment levels. So as a group, 00:11:13.360 --> 00:11:15.659 the treatment did improve symptoms and function 00:11:15.659 --> 00:11:18.580 overall. Correct. On average, patients felt better 00:11:18.580 --> 00:11:20.299 and functioned better than before the treatment 00:11:20.299 --> 00:11:22.500 started. Okay, overall improvement is good news. 00:11:22.750 --> 00:11:24.970 But this is where, as you say, the devil is often 00:11:24.970 --> 00:11:27.690 in the detail. What did the functional outcomes 00:11:27.690 --> 00:11:29.669 look like when you broke them down by the type 00:11:29.669 --> 00:11:32.710 of final treatment? So comparing the RTSA group 00:11:32.710 --> 00:11:35.250 versus the hemi -arthroplasty group versus those 00:11:35.250 --> 00:11:37.549 who just retained the spacer. This is where it 00:11:37.549 --> 00:11:39.629 gets really interesting, I think. Indeed it is. 00:11:39.809 --> 00:11:41.809 This is where we saw quite marked differences. 00:11:42.210 --> 00:11:44.230 Patients who completed the full stage process 00:11:44.230 --> 00:11:46.870 and received a reverse total shoulder arthroplasty, 00:11:47.029 --> 00:11:50.909 the RTSA, in the second stage showed a significant 00:11:50.909 --> 00:11:54.019 functional improvement. Their mean constant scores 00:11:54.019 --> 00:11:57.059 increased notably, from about 31 pre -op to 51 00:11:57.059 --> 00:12:00.220 post -op. A definite jump there. Yes. However, 00:12:00.600 --> 00:12:02.639 those patients who received a hemiarthroplasty 00:12:02.639 --> 00:12:05.179 in the second stage, and also those who permanently 00:12:05.179 --> 00:12:08.240 retained the cement spacer, did not show statistically 00:12:08.240 --> 00:12:10.279 significant improvement in their constant and 00:12:10.279 --> 00:12:13.019 Murley scores. No significant improvement in 00:12:13.019 --> 00:12:15.519 those two groups. That's right. For the HA group, 00:12:15.539 --> 00:12:18.840 the mean score went from about 22 to 24, basically 00:12:18.840 --> 00:12:21.419 unchanged. For the spacer group, it went from 00:12:21.419 --> 00:12:25.379 18 up to 35, which sounds like an increase, but 00:12:25.379 --> 00:12:28.279 the p -value was 0 .093, so it didn't meet the 00:12:28.279 --> 00:12:30.179 threshold for statistical significance in our 00:12:30.179 --> 00:12:33.539 analysis. Wow. That functional disparity between 00:12:33.539 --> 00:12:36.220 the RTSA group and the others is really quite 00:12:36.220 --> 00:12:39.879 stark. Does this finding mean that RTSA is inherently 00:12:39.879 --> 00:12:43.240 functionally superior for these PGI cases? Or 00:12:43.240 --> 00:12:46.220 perhaps that HA, or just retaining the spacer, 00:12:46.500 --> 00:12:49.059 are simply poor options for function after infection? 00:12:49.519 --> 00:12:51.600 That's a really crucial point of interpretation, 00:12:52.120 --> 00:12:54.460 and one the authors, including myself, discussed 00:12:54.460 --> 00:12:57.179 at length. The functional difference wasn't necessarily 00:12:57.179 --> 00:13:00.240 simply due to the type of implant itself. The 00:13:00.240 --> 00:13:02.279 significant factor was almost certainly the baseline 00:13:02.279 --> 00:13:03.919 condition of the patient and their shoulder. 00:13:04.539 --> 00:13:07.240 Patients who ended up receiving an HA typically 00:13:07.240 --> 00:13:09.980 had severe glenoid bone loss, as we discussed. 00:13:10.190 --> 00:13:13.330 That necessitated using it as a salvage option. 00:13:14.129 --> 00:13:16.529 Their potential for functional recovery was already 00:13:16.529 --> 00:13:19.029 limited from the very start, regardless of the 00:13:19.029 --> 00:13:20.909 implant. Because the foundation wasn't there. 00:13:21.190 --> 00:13:24.350 Precisely. Similarly, patients who retained the 00:13:24.350 --> 00:13:27.610 spacer often did so because of significant medical 00:13:27.610 --> 00:13:31.110 comorbidities or being deemed unfit or inoperable 00:13:31.110 --> 00:13:34.190 for a second stage. Again, this selects for a 00:13:34.190 --> 00:13:36.669 group with lower baseline functional potential 00:13:36.669 --> 00:13:40.059 and perhaps lower demands. I see. So the key 00:13:40.059 --> 00:13:42.559 takeaway here isn't necessarily that RTSA causes 00:13:42.559 --> 00:13:45.299 better function in PJI, but more likely that 00:13:45.299 --> 00:13:47.360 the patients who were actually eligible for an 00:13:47.360 --> 00:13:51.000 RTSA in stage two were already a different, perhaps 00:13:51.000 --> 00:13:53.320 healthier cohort with better underlying bone 00:13:53.320 --> 00:13:55.679 stock to begin with. Exactly that. Their better 00:13:55.679 --> 00:13:57.419 starting point allowed for greater functional 00:13:57.419 --> 00:14:00.299 recovery potential. The patient's initial condition 00:14:00.299 --> 00:14:02.259 seems to be the major predictor of the functional 00:14:02.259 --> 00:14:04.759 gain you can achieve, particularly in those most 00:14:04.759 --> 00:14:06.580 compromised cases where options are limited. 00:14:06.750 --> 00:14:08.929 That makes a lot of sense. It's about the patient 00:14:08.929 --> 00:14:11.450 factors as much as, or maybe even more than, 00:14:11.809 --> 00:14:14.250 the hardware choice in the end stage for these 00:14:14.250 --> 00:14:17.149 really complex cases. It highlights the critical 00:14:17.149 --> 00:14:20.409 importance of patient selection, managing expectations 00:14:20.409 --> 00:14:22.470 realistically based on their initial condition, 00:14:22.889 --> 00:14:25.129 the state of their bone, particularly the glenoid, 00:14:25.350 --> 00:14:28.769 and their overall health. Now, the paper also 00:14:28.769 --> 00:14:31.009 highlights complications. This is complex, high 00:14:31.009 --> 00:14:34.129 -risk surgery. We know that. What was the complication 00:14:34.129 --> 00:14:37.379 rate actually like in this series? Well, unfortunately, 00:14:37.759 --> 00:14:39.440 and perhaps unsurprisingly, given the nature 00:14:39.440 --> 00:14:41.860 of the problem, complications were common. They 00:14:41.860 --> 00:14:45.100 occurred in 58 % of the patients in this study 00:14:45.100 --> 00:14:48.440 cohort. 58 %? That's more than half. It is. It 00:14:48.440 --> 00:14:50.860 really underscores the inherent difficulty and 00:14:50.860 --> 00:14:53.080 the significant morbidity associated with treating 00:14:53.080 --> 00:14:56.139 established shoulder PGI. This high rate also 00:14:56.139 --> 00:14:58.419 led to a substantial number of patients requiring 00:14:58.419 --> 00:15:01.860 further revision surgery down the line. 35 % 00:15:01.860 --> 00:15:05.720 overall needed more operations. Wow, 58 % complication 00:15:05.720 --> 00:15:08.279 rate and 35 % needing further revision. That's 00:15:08.279 --> 00:15:10.639 substantial. What were the most frequent complications 00:15:10.639 --> 00:15:12.929 that you observed? The most common issues we 00:15:12.929 --> 00:15:15.289 documented included things like progressive glenoid 00:15:15.289 --> 00:15:18.549 destruction, bone loss on the socket side, occurring 00:15:18.549 --> 00:15:20.850 after the spacer was implanted but before re 00:15:20.850 --> 00:15:24.149 -implantation, also post -operative hematoma, 00:15:24.470 --> 00:15:27.090 subsequent shoulder instability after re -implantation, 00:15:27.509 --> 00:15:29.750 wound healing problems, which are always a concern, 00:15:30.549 --> 00:15:33.009 aseptic loosening of the eventual implant, meaning 00:15:33.009 --> 00:15:35.669 loosening not due to infection, and periprosthetic 00:15:35.669 --> 00:15:38.389 fractures around the implant or bone. The rates 00:15:38.389 --> 00:15:41.049 did vary slightly across the subgroups, but that 00:15:41.049 --> 00:15:44.250 overall figure of 58 % is a clear reminder of 00:15:44.250 --> 00:15:46.429 the challenges involved here. Definitely sobering 00:15:46.429 --> 00:15:50.309 figures. The study also, quite rightly, acknowledges 00:15:50.309 --> 00:15:52.450 its own limitations. What are the key points 00:15:52.450 --> 00:15:54.789 the authors mention there? Yes, we were upfront 00:15:54.789 --> 00:15:57.269 about those. Firstly, it's a retrospective study, 00:15:57.370 --> 00:15:59.429 meaning we look back at data already collected 00:15:59.429 --> 00:16:01.649 rather than a prospective trial designed from 00:16:01.649 --> 00:16:04.129 the start. That has inherent limitations. As 00:16:04.129 --> 00:16:06.230 we've just discussed at length, we highlighted 00:16:06.230 --> 00:16:08.350 the significant baseline differences between 00:16:08.350 --> 00:16:11.529 the treatment subgroups RTSA, HA, SPACER, DATA 00:16:11.529 --> 00:16:14.169 as a major limitation when trying to directly 00:16:14.169 --> 00:16:16.649 compare their functional outcomes. There weren't 00:16:16.649 --> 00:16:19.330 equivalent groups to start with. The relatively 00:16:19.330 --> 00:16:22.629 small numbers in the HA and the SPACER subgroups 00:16:22.629 --> 00:16:25.389 also limit the statistical power of those specific 00:16:25.389 --> 00:16:28.129 analyses. You have to be cautious interpreting 00:16:28.129 --> 00:16:30.980 results from small groups. And finally, there 00:16:30.980 --> 00:16:34.620 was some loss to follow up. About 21 % of the 00:16:34.620 --> 00:16:37.240 original cohort couldn't be included in the final 00:16:37.240 --> 00:16:39.500 analysis for various reasons, which is quite 00:16:39.500 --> 00:16:41.720 common in long -term surgical studies, but still 00:16:41.720 --> 00:16:44.440 a limitation to acknowledge. Understood. So pulling 00:16:44.440 --> 00:16:46.580 all this together now, the study confirms that 00:16:46.580 --> 00:16:48.460 this two -stage approach is highly effective 00:16:48.460 --> 00:16:51.799 for infection control, achieving that 95 % rate. 00:16:52.299 --> 00:16:54.460 But functional recovery seems strongly linked 00:16:54.460 --> 00:16:57.120 to patient factors and whether they can actually 00:16:57.120 --> 00:17:01.009 proceed to an RTSA. What are the broader implications 00:17:01.009 --> 00:17:03.389 of this for orthopedic surgeons who are considering 00:17:03.389 --> 00:17:06.269 treatment options for shoulder PGI? Well, I think 00:17:06.269 --> 00:17:08.750 it clearly validates the potential for a high 00:17:08.750 --> 00:17:11.029 success rate in terms of infection eradication 00:17:11.029 --> 00:17:14.069 using this demanding two -stage pathway, even 00:17:14.069 --> 00:17:16.369 in complex referral cases. That's a positive 00:17:16.369 --> 00:17:19.049 message. However, the discussion section in the 00:17:19.049 --> 00:17:21.390 paper thoughtfully brings up the comparison to 00:17:21.390 --> 00:17:23.650 single -stage exchange procedures. Right, doing 00:17:23.650 --> 00:17:26.529 it all in one operation. Exactly. Some studies 00:17:26.759 --> 00:17:29.619 investigating single -stage exchange, particularly 00:17:29.619 --> 00:17:32.140 perhaps for less virulent organism or different 00:17:32.140 --> 00:17:35.319 patient groups, report comparable infection control 00:17:35.319 --> 00:17:38.259 rates to the two -stage method. So given the 00:17:38.259 --> 00:17:41.099 high complication rate we saw, the patient burden 00:17:41.099 --> 00:17:43.720 of multiple surgeries inherent in the two -stage 00:17:43.720 --> 00:17:46.759 method, especially if the specific pathogen isn't 00:17:46.759 --> 00:17:49.779 known right at the beginning. Well, the single 00:17:49.779 --> 00:17:52.240 stage approach becomes a very significant point 00:17:52.240 --> 00:17:55.440 of comparison and ongoing debate. It really highlights 00:17:55.440 --> 00:17:57.799 that tension, doesn't it? Balancing the absolute 00:17:57.799 --> 00:18:00.119 priority of getting rid of the infection versus 00:18:00.119 --> 00:18:02.740 the goal of restoring function and minimizing 00:18:02.740 --> 00:18:05.599 the overall impact and risk to the patient. That's 00:18:05.599 --> 00:18:07.920 precisely the crux of it. It's not just about 00:18:07.920 --> 00:18:09.619 clearing the infection anymore, although that 00:18:09.619 --> 00:18:11.599 remains critical. It's about finding the optimal 00:18:11.599 --> 00:18:14.180 path, the best strategy for achieving a functional 00:18:14.180 --> 00:18:16.619 outcome with the lowest acceptable risk profile 00:18:16.619 --> 00:18:19.460 for that specific individual patient. It forces 00:18:19.460 --> 00:18:21.660 a really careful individualized assessment, doesn't 00:18:21.660 --> 00:18:23.400 it? Looking at the patient's overall health, 00:18:23.720 --> 00:18:25.859 the specific bug involved, the state of their 00:18:25.859 --> 00:18:27.799 bone, and what they can realistically tolerate 00:18:27.799 --> 00:18:30.500 and ultimately benefit from. Exactly. There's 00:18:30.500 --> 00:18:34.140 no single one -size -fits -all answer in treating 00:18:34.140 --> 00:18:36.539 shoulder PJI. Let's run through a quick lightning 00:18:36.539 --> 00:18:38.640 round then for some rapid -fire takeaways based 00:18:38.640 --> 00:18:41.279 directly on this research. Quickest win for infection 00:18:41.279 --> 00:18:43.839 control, according to this study. The two -stage 00:18:43.839 --> 00:18:48.190 method itself. It yielded that 95 % success rate 00:18:48.190 --> 00:18:51.329 for eradication. Most common culprits identified 00:18:51.329 --> 00:18:53.930 in this particular cohort. Coagulus negative 00:18:53.930 --> 00:18:57.009 staphylococci and P. acnes were the top two. 00:18:57.470 --> 00:18:59.549 Biggest predictor of functional improvement noted 00:18:59.549 --> 00:19:02.269 in this study. It seemed to be the patient's 00:19:02.269 --> 00:19:05.430 underlying condition and their bone stock, specifically 00:19:05.430 --> 00:19:08.009 whether it allowed for an RTSA to be performed 00:19:08.009 --> 00:19:11.369 in the second stage. A key diagnostic consideration 00:19:11.369 --> 00:19:14.009 highlighted for shoulder PGI, especially when 00:19:14.009 --> 00:19:16.289 you suspect P -acnes. Extended culture times 00:19:16.289 --> 00:19:19.029 are crucial, at least 10 days incubation. And 00:19:19.029 --> 00:19:21.910 one major challenge reeled starkly by the complication 00:19:21.910 --> 00:19:24.829 rates. The significant inherent morbidity. The 00:19:24.829 --> 00:19:26.750 risk of complications and the potential need 00:19:26.750 --> 00:19:29.390 for further surgery remain very high in treating 00:19:29.390 --> 00:19:32.170 these complex infections. Excellent summary points. 00:19:32.569 --> 00:19:35.769 Okay, let's crystallize the core actionable takeaways 00:19:35.769 --> 00:19:38.539 from this deep dive for our listeners. What should 00:19:38.539 --> 00:19:40.920 they really remember from this? Okay. Firstly, 00:19:41.059 --> 00:19:43.440 this study reinforces that two -stage resission 00:19:43.440 --> 00:19:46.119 using antibiotic spacers is a highly effective 00:19:46.119 --> 00:19:49.200 method for controlling shoulder PGI, achieving 00:19:49.200 --> 00:19:52.359 a 95 % success rate in this particular series 00:19:52.359 --> 00:19:55.180 of complex cases. Good. Takeaway number two. 00:19:55.539 --> 00:19:58.000 Secondly, restoring good shoulder function after 00:19:58.000 --> 00:20:00.920 treating PGI appears to be strongly linked to 00:20:00.920 --> 00:20:03.339 the patient's suitability for receiving a reverse 00:20:03.339 --> 00:20:06.140 total shoulder arthroplasty in the second stage. 00:20:06.400 --> 00:20:09.039 and that suitability is largely driven by their 00:20:09.039 --> 00:20:12.960 underlying condition and bone quality. Thirdly, 00:20:13.180 --> 00:20:15.799 baseline patient factors, particularly the extent 00:20:15.799 --> 00:20:18.839 of glenoid bone destruction, significantly influence 00:20:18.839 --> 00:20:20.759 both the treatment pathway that can be chosen 00:20:20.759 --> 00:20:23.119 and the ultimate potential for functional recovery. 00:20:23.500 --> 00:20:25.440 This is often more critical than the specific 00:20:25.440 --> 00:20:27.480 implant used in the most challenging salvage 00:20:27.480 --> 00:20:32.420 situations. Fourthly, accurate diagnosis of shoulder 00:20:32.420 --> 00:20:36.410 PGI requires diligent protocols. Especially important 00:20:36.410 --> 00:20:39.009 is using extended culture times of at least 10 00:20:39.009 --> 00:20:42.490 days, particularly to detect those slow growing 00:20:42.490 --> 00:20:45.029 organisms like P. acnes. Don't miss the bug. 00:20:45.309 --> 00:20:48.049 Crucial point. Fifth. Fifthly, be aware that 00:20:48.049 --> 00:20:50.650 this is complex surgery with a notable risk of 00:20:50.650 --> 00:20:54.230 complications. Nearly 60 % in this series experience 00:20:54.230 --> 00:20:56.470 one, and there's a significant chance around 00:20:56.470 --> 00:20:59.549 35 % of needing further revision surgery down 00:20:59.549 --> 00:21:02.589 the track. Finally, the study's discussion and 00:21:02.589 --> 00:21:04.849 our conversation today really prompts important 00:21:04.849 --> 00:21:07.369 consideration of alternative strategies like 00:21:07.369 --> 00:21:09.829 single -stage revision. These might offer comparable 00:21:09.829 --> 00:21:12.230 infection control with potentially less patient 00:21:12.230 --> 00:21:14.609 burden in certain situations, highlighting the 00:21:14.609 --> 00:21:16.970 ongoing need to evaluate the optimal approach 00:21:16.970 --> 00:21:19.579 for different PGI scenarios in patients. Professor 00:21:19.579 --> 00:21:21.380 Immam, thank you so much for guiding us through 00:21:21.380 --> 00:21:23.740 this research and providing such clear, really 00:21:23.740 --> 00:21:26.119 insightful analysis. Your expertise as an author 00:21:26.119 --> 00:21:27.859 on the paper has been absolutely invaluable. 00:21:28.039 --> 00:21:29.880 It was my pleasure entirely. Glad to discuss 00:21:29.880 --> 00:21:32.450 it. If you found this deep dive valuable, please 00:21:32.450 --> 00:21:34.750 do consider leaving a rating or perhaps sharing 00:21:34.750 --> 00:21:37.309 it with a colleague on LinkedIn or X. And to 00:21:37.309 --> 00:21:39.109 leave you with a final thought based on our discussion 00:21:39.109 --> 00:21:41.589 today, given the high infection control rate 00:21:41.589 --> 00:21:43.549 with those variable functional outcomes and the 00:21:43.549 --> 00:21:45.690 significant complication risks associated with 00:21:45.690 --> 00:21:48.369 this two -stage approach, how should we as an 00:21:48.369 --> 00:21:50.690 orthopedic community best balance that aggressive 00:21:50.690 --> 00:21:53.150 infection eradication with the equally crucial 00:21:53.150 --> 00:21:55.589 goals of functional restoration and minimizing 00:21:55.589 --> 00:21:58.950 patient burden in these incredibly complex shoulder 00:21:58.950 --> 00:22:01.680 PJI cases? cases. Something come all over. That's 00:22:01.680 --> 00:22:04.000 all for this deep dive. Join us next time as 00:22:04.000 --> 00:22:05.519 we unpack another stack of sources.