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Good afternoon. I'm Lucy Mailing the outgoing Tig fellow. So thumb base arthritis, the end this algorithm encapsulates the vast majority of what you need to know about the topic and certainly enough to score those frcs points. I'm happy to share both this and my slides with you at the end. So no need to furiously scribble notes. So as with any exam answer, let's break it down into different steps. Firstly, assessment who gets it commonly, it's middle aged women and into older age. And this may be partly reflected by greater laxity in females. We also see it in manual working men and this may be secondary to the extreme forces that can pass through the joint, but really it can affect anyone. And since 1000 Newtons can routinely pass through the CMC joint, it is unsurprisingly the third commonest joint to be affected in a patients will complain of pain, limiting their daily activities and that pain may be generated by a number of different factors seen here on the left. So what do we see? Well, the thumb base may be square and that's due to loss of integrity of the anterior oblique or peak ligament allowing the thumb metacarpal to sublux proximally and dorsally. 1 may see az shaped thumb where a stiff CMC joint compensates with MCP hyperextension. In order to preserve the grasp, we need to examine the CMC joint for pain and the lever test where one tries to shuck, the metacarpal in a radio ulnar direction has the greatest diagnostic value more so than the grind test. We need to assess the STD T joint as this may be an alternative or an additional source of pain. And to examine this, if you hold the patient's forearm and their hand, but do not touch any of the thumb, you can apply an axial load with radio ulnar deviation and this stresses the S TT it's worth checking. Somebody's baton score as laxity can be an important factor with this condition. Remember that carpal tunnel syndrome is a garnish to many other hand conditions. And a third of patients who have carpal tunnel will have X ray signs of thumb base oa and vice versa. Lots of people with tha will also have carpal tunnel syndrome. Differential diagnoses include anything else over the radial side of the wrist. Investigation wise, plain films will usually suffice, we can ask for bets and Robert's views. Now, I can't remember who is who, but they always come as a pair and these are the true pa and lateral views centered on the CMC joint. There's always a classification to remember, but the eaten little. Its only purpose is in an exam situation. So the classification does not influence treatment or describe the success of any particular treatment given next information. So we've made a diagnosis of CMC osteoarthritis. What information needs to be imparted? Remember that as per the good medical practice guidance, it's a partnership with a patient. So it must flow both ways. Patients are delighted to learn that 85% of them do not ever need surgery. We must tell them that different options exist but that will individualize the plan to suit them and always give handouts in return. Don't forget to exploit your patient. Give me your outcome data and please contribute to our evidence base that is woefully lacking. I anticipate. There will be very soon. An RCT looking at two popular surgical options which we'll come to shortly. So you're tallying up points in your viva already and you've not actually done any treatment yet hand therapy. There is no risk in trying hand therapy. And as we saw earlier, the vast majority of patients don't need surgery. So it must be working for many therapy typically comprises splintage and exercise and there's no consensus over which splint is better or which exercise program is better. Our therapist will help guide the patients and reassure them that joints are healthier when used and moved and that pain doesn't equal harm next injections. So we're getting a bit more invasive now and we're not the Paris Olympics. So we don't mind a few roids. Remember our joyous fact that the eaten little stage doesn't influence the success of treatment. Therefore, you can pretend that you've actively chosen not to commit it to your memory. And you're gonna offer a steroid injection in any grade of radiographic oa. And we can use these steroids for diagnostic and therapeutic purposes. It's quite helpful to isolate either the CMC or the S TT joint to see which is the main source of the pain. One study found that ultrasound guided in ultrasound, guided injections are more reliable than blind clinic injections. But they're not really practical. And to be honest, it's not difficult to find the CMC joint in someone with arthritis co that metacarpal base is so square, you just pop in slightly proximal to it. It helps to ask the patient to pull on their own thumb to help open up that joint space. If injecting the S TT joint, you needn't do that under image guidance either because you can simply put the injection into the radiocarpal joint just as you would put the needle for a joint aspiration of the wrist. Because the radiocarpal and midcarpal joints are connected, that steroid will work its way up and reach the S TT. The effectiveness of steroids is slightly unpredictable. So about half of patients will have three months relief, they're pretty safe. But we need to beware them. If we're looking at future metalwork surgery, particularly arthroplasty, other injections are available but not in routine use within the NHS. And that's as they have not been proven to be superior or particularly cost effective. And only at step five, do we reach our happy place theaters? This is an extremely hectic slide and I apologize for that, but we'll work through it down this right hand column where you can see a number of different options for surgical treatment of thumb base. Oa I've split these into joint preserving and joint sacrificing. The decision making process involves disease factors, patient factors and surgical factors. So let's start in the Northwest corner for mild disease. There are very limited indications for surgery because we should still be on our conservative therapies at this stage. But some keen arthroscopies may offer this to help plan future procedures or offer a bit of a tidy up in more moderate disease. If the problem is laxity plus pain ie instability, then a soft tissue procedure may be indicated. Commonly, this is the Eaton littler procedure where a slip of FCR is rooted through that metacarpal base to bring it back into position. And then there are a number of other joint preserving procedures including denervation and osteotomy. Denervation is slightly unpredictable, but those that favor it. Quote, it's rapid recovery time. So it might be a good option for the self employed. Osteotomies are an option for patients who have partial uh joint involvement and that might be sensible for patients who are lower, lower activity and not likely to wear out the entire joint straight away in higher demand. Manual workers fusing the joint is preferable and we're now into salvage procedures and that's purple territory. Once the disease is severe, the main choice is between a hand girdlestone or trapeziectomy and a joint replacement. And elderly patients may find themselves in this uh a category or heading more rapidly to a joint sacrificing procedure as durability is less crucial. Here's a list of just some risks and benefits of each choice which is by no means exhaustive. You'll see that trapeziectomy is circled in gold and that's because it's considered by many to be the gold standard or the default operation. Trapeziectomy is simple, fast, cheap and has a long track record. In fact, this year is its uh 75th birthday, having been invented at Royal Tunbridge Wells by vis it is 80 to 90% successful. So it's the knee replacement of hands. The downside is that it can take a long time to recover typically six months or so before the patient will. Thank you. It can be performed from the front. That's the Wagner approach or the back, the dorsal approach. And the AO website describes these really beautifully. It's just a case of picking your poison. Do you want to encounter the radial artery and branches of the superficial radial nerve or do you want to obliterate the termination of the lateral cutaneous nerve of the forearm, dorsal approach does jeopardize the blood supply. And so it might be worth avoiding that in an osteotomy setting or effusion setting. But the dorsal approach is also the only option if you're doing an arthroplasty. So it might be worth trying. Both trapeziectomy can be done piecemeal where the bone is broken into small pieces and taken out as crumbs. Or if you're very clever, you can take it out as one big block. It's important to take only the trapezium and preserve the surrounding bones and soft tissues. If there is still an intermetacarpal ligament that is worth keeping without that, the thumb metacarpal can collapse down and a butt against the scaphoid. And then we've got a new problem of pain to avoid this happening. Some people will stabilize the joint and this can be done by reconstructing the ligament using a slip sling of apla slip of FC ra little anchovy of palmaris rolled up into the gap, ak wire temporarily a tightrope between the metacarpals or even fusing the metacarpals. The one piece of literature you need to remember for the exam is the Davies randomized control trial which compared simple trapezectomy versus that with stabilization. And we've now got 18 years of follow up from that published in the American Journal of hand surgery 2012. And as you can predict like all randomized controlled trials, no difference was found. But the pragmatic answer is to test on the table and if the patient is collapsing down onto this gid, it might be worth stabilizing and this is more applicable to those who have inherent laxity. So let's talk about the other commonplace operation that is gaining rapidly in popularity and that's arthroplasty. So, Arthroplasty is an alternative to trapeziectomy, but not everybody is eligible. The main pre requisites are that the patient must have an asymptomatic S TT joint as more force will be heading through this and the trapezium must be big enough to house the cup. So it needs to be six millimeters tall, at least arthroplasty should be done. Ideally, in a research setting, we must collect joint registry data and the surgeon performing should do a reasonable volume of these. Now, a reasonable volume has yet to be determined. But these are all things that enable us to gir various different designs have existed over the years. But we're currently on the third generation metal on poly modular ball and socket design. And this is therefore more like the hip replacement of hands. But time will tell whether the outcomes will match proponents of joint replacements will quote a restoration in length, a lessening of subluxation correction of mcp hyperextension, good aesthetic satisfaction, better strength and faster rehab as the advantages to Trapeziectomy and the Swedish registry shows that most of these patients will return to work within three months, which is quicker than the Trapezectomy. But not all papers have demonstrated this yet. Survivorship is about 90% at 10 years, but we're still lacking the long term results. So, what are the disadvantages of joint replacement? Well, it's a longer procedure. It's more complicated and it's certainly more expensive initially. But the long term, uh, costs haven't been fully equated. For example, do they have fewer trips to plaster room, fewer hand therapy appointments, et cetera. There is a risk of infection, wear, loosening, fracture and dislocation with joint replacements. And if you keep an eye out for the revered systematic review by mailing et al in the journal of hand surgery, you will find that the dislocation rate is actually just half a percent with the current dual mobility designs, dual mobility is preferable to single mobility for such a tiny joint because you can imagine the jump distance is just millimeters. Importantly, if one has a joint replacement and something goes wrong, one can revert to trapeziectomy with equally good results as if that trapeziectomy had been performed primarily. So there's a backup plan. Good medical practice says that we must offer all reasonable treatment options to a patient even if we do not perform it ourselves. So far, the arthroplasty hasn't been shown to be superior, but there is increasing evidence to support it. And I think it would be remiss to not mention it at all. So let's move on to some cases. This is a 55 year old cleaner. The x rays show osteoarthritis at the CMC joint, she was previously treated on the right side with a trapeziectomy with which she was delighted. And so if somebody is happy with the previous treatment, it's bold, perhaps careless to change it. And so she was given a matching pair and she is indeed very happy with this next case. It's a 60 year old secretary and she was noted preoperatively to be quite lax and it looks like that joint is quite wobbly. And on the table, the metacarpal sunk back down and abutted against the scaphoid. So she was given a stabilization. Remember, there are many ways of doing this. But if somebody has an inherent collagen problem, then using their own tendons to reconstruct, the intermetacarpal ligament might not be the wisest move. So she got a tightrope and the aim of the tightrope is to jack the first metacarpal up against the second, not too tight because then you'd get pain from impingement, but more than we've got here. And you can see that this hasn't really brought it out to length at all. And in fact, the metacarpal base is still against the, the scaphoid. I would caution use of this device because even if the tension is set appropriately, look at where that um ulnar sided button lives and how can you really be sure you haven't captured the neurovascular bundle with that. Next up, we have got a potential complication following trapeziectomy here, the patient has got a large residual into metacarpal osteophyte. And this was so big that it was mistaken for the trapezoid. And when I went back in to operate, I could easily see why it was mistaken for this. So there's no shame of using II intraoperatively and particularly while starting out whilst there is moderate shame of leaving this in and deep, deep shame of taking out the scaphoid by accident. And believe me, it has happened, remember that the trapezium in osteoarthritis is going to be craggy and huge. And if you're taking out piecemeal, the crumbs, you collect will be so abundant. You will fear that you've accidentally done APR C. But don't worry use II if in doubt and this was her afterwards, you can see that big gap opening up where the um osteophyte once was. I should note that this was also a member of staff, which is typical. All problems happen in people that you don't want them to. So this is a 75 year old patient who many years ago had had her trapezium out and repented with pain and deformity in the MCP joint. And you can see that due to a lifetime of uh laxity here, this joint has now worn out and so it was fused. This is the apex device from lavender medical but other options are available. This is a 50 year old patient who has got preservation of their trapezial height and no clinical S tt arthritis out of the options. Trapezectomy versus arthroplasty. They opted for the latter and this is how it looks. It's just a tiny chinchilla's hip replacement and the implant on the right hand side is the one we use. And that's the dual mobility mir. So it's an uncemented modular um metal and poly design. There are a few other implants available, all of which are based around the same, same design principles. What's nice is that in small joint arthroplasty, we can borrow all of the knowledge that our large joint arthroplasty colleagues uh have have generated over the years to avoid uh re creating problems from the past. And then last but not least 55 year old gentleman who works as a hairdresser. Now, he had a lot of pain on dart throwers motion and on stressing his S tt joint with axial load and radial ulnar deviation, there was a lot of pain. So the options here would be to fuse the ST it's quite a small surface area to to encourage to heal and non union is a problem or you can do the old trusty trapeziectomy. And at the same time, shave off a bit of the ST articulation, be it distal scaphoid or proximal trapezoid and that's what he had. So in summary, this is your mind map of what to talk about when faced with thumb. CMC arthritis. I hope it's been helpful. And as I said, I'm happy to share these slides with anyone who would like them and there's far too many references that remember Davis? Thanks very much.