The first step to recovery is addressing pain
When dealing with dysfunction, addressing pain should be the first step. There is no point in implementing strengthening programmes until the horse is pain-free and can benefit from strengthening.
Pain needs to be addressed before we implement any kind of strengthening programme.
People often ask what exercises they should do with their horse that has xyz condition. Should you do belly lifts for a weak back? Should you do pelvic tilts for stronger loins? Should you do cavaletti work for a weak thoracic sling? These questions are very difficult to answer because it really, really, really depends on the case.
The problem with giving advice without seeing the horse and understanding its exact issues is that the same exercise can be either greatly beneficial or highly detrimental, depending on where on the rehabilitation spectrum the horse is. If the horse has a weak core, you might be tempted to implement a core strengthening regime including exercises like carrot stretches, belly lifts or pelvic tilts. But we can't know for sure if we can do those safely until we understand WHY the horse has a weak core. In most cases, the core is weak because the postural muscles aren't doing their job. Very often the postural muscles aren't doing their job because there's a dysfunction. And dysfunction is very often connected to pain. So, very often there is pain that is preventing the horse from using the appropriate musculature during movement. And if we just stack strengthening exercises on top of that dysfunction, we will often get the opposite result of what we want. The horse will become more painful, stiffer and even weaker.
The first step of any rehabilitation programme is to address pain. Until the horse is (more or less) pain free, our only job is to get rid of the pain. Sometimes this will mean rest, sometimes it will mean a couple of sessions of good manual therapy, sometimes it will mean a veterinary intervention including injections. Unfortunately, owners often decide for one or the other when it comes to bodywork vs injections. But truthfully, in a lot of cases, it should be both. Some owners will want to stay away from injections and will opt for different kinds of bodywork, and yes, sometimes that is enough. But often, the horse could use a little extra help to calm down the chronic inflammation. On the other hand, some owners tend to do injections and think that will solve all their problems. But, the injections in themselves are just the first step. They take away the pain and dial down the inflammation so that then the real rehabilitation can begin. If you just do injections the horse will get better for a bit, but the problem will come back because the cause wasn't addressed. It's like taking an aspirin for a gaping wound on your head. Sure, the pain will go away for a little bit, but until we do something about the wound, the pain will keep coming back when the medication subsides.
So, when we are dealing with any kind of dysfunction in the horse, we need to understand that there are no quick fixes. We need to understand that rehabilitation has several stages and we can't just pick and choose which stage we want to do and disregard the rest. We need to address the pain, we need to fix the imbalances, we need to strengthen. And we need to do all three in that order. There are no shortcuts.