Dr. Yumi Mitsuya presents "Approach to Delayed Walking" at the UCSF Pediatric Musculoskeletal and Sports Medicine Conference 2023 in Berkeley, CA.
Right, everyone, we're going to move on to our afternoon block. I hope everyone had a filling lunch but not too filling. Um I, I I'm gonna be doing the intros for this afternoon, um which mostly consists of our like neuromuscular rehab crew. So first up is Dr Yumi Mitsu. I have the pleasure of introducing her. We have offices just next to each other and I get to see work with her um frequently. So uh doctor, I went to medical school at Albany Medical College in New York and then she came to um Children's Oakland at the time was called that for residency uh in pediatrics. And then she did a second separate residency in adult physical medicine and rehabilitation at Stanford University. So that's it. Hi everyone. Thank you, Doctor Noah for the introduction. I'm really happy to be here to um kick off the rehab afternoon with my team. I see some familiar faces in the audience, so good to see you all. Um The title of my talk today is called The Approach To a Child with Delayed Walking and I have no disclosures. Um Here's an outline of what I hope to accomplish with today's talk um this like a really familiar topic to this audience already, but we'll first review expected motor milestones and what constitutes motor delay. And then we'll review the neuromotor exam and outline an algorithm for surveillance and screening of Children who has motor delay. I'll list some red flags that should prompt referral to a subspecialist like a psychiatrist or a neurologist when there are concerns. Um And then I'll describe typical gate development and some common structural and gate variations in the young child and also talk about role of um orthosis in some of these conditions. So this is probably a familiar clinical scenario you may see in your clinic during well child visits and it's a common referral reason to our uh P DB clinic. So an 18 month old with no significant birth history or past medical history who maybe met early milestones but didn't crawl until about 11 months and from there making some steady progress and now cruising on furniture, but at 18 months, not yet walking independently. So, is this maybe a mild form of cerebral palsy? Another neurological abnormality or primary muscle disorder causing weakness? Do they have um any structural abnormalities of their legs or feet that's affecting their mechanics or are they otherwise typically developing cognitively and in fine motor skills and simply have some delay in gross motor development? Um And we'll catch up later on. So before we get into the neuromotor, um evaluation I want to first review the updated motor milestones for developments for surveillance, which was put out by the CDC and A P um in pediatrics in March of last year 2022. So the CDC funded the A P to form an expert working group to revise the developmental surveillance checklist, updating the most expected, the expected age uh um which most defined greater than 75% of Children would be expected to achieve a certain milestone. And the main changes was that there were uh some milestones added for 15 and 30 month house super vision visits and about a third of previous milestones um were transferred to different ages. Majority of the la later ages than previous. Huh? Looks like there we go. Um So here's a chart of the milestones that were previously used that we're all familiar with. I'm sorry, the text is kind of small um but lifting head and chest and prone at two months, rolling from prone to supine at four months and from Supine and prone by six months sitting without support at six months and walking independently at 12 months. And the general rule for what constituted a delay that would warrant further evaluation or early intervention was that if a child was two months delayed or reaching milestones in the first year of life or four months delayed in the second year of life. Um Correcting for prematurity for the first two years of life, if they were born premature earlier than 36 weeks of gestation, then um you had a delay. So these were um the main ages at which a child was expected to achieve the milestone with the updated milestones instead of the mean age. Now, it's the age where greater than 75% are expected to have achieved the milestone. So um if they have not achieved that milestone at that age, then it's considered a delay. So the um the new milestone age is similar for the first four months. Um holding head up at two months, bringing hand to mouth at four months, rolling from prone to the pine is now at six months, sitting without support is now at nine months and pulling up the stand is at 12 months and then taking a few independent steps is now by 15 months and walking independently is actually um it went from 12 months to 18 months. Um So if they're not doing these things by that age, it warrants for their evaluation. Although in a lot of cases, you know, if these um delays may not be in isolation, like just a grows motor delay. So still in a lot of cases, they're being referred earlier for early intervention or uh evaluation. And even though the surveillance guidelines now give a child until 18 months to be walking on their own. By about 14 to 15 months, most parents and I think as providers too will have at least some concern if the child is not yet close to walking. And then for the toddlers who have started to take steps or walk, parents might be expressing concern about the quality of their toddlers gate as well as some possible structural concerns. Like their feet are looking kind of funny or their look, their walking patterns kind of funny. So our role as providers start with a thorough review of their birth and development history, of course, and a family history and a neurological and muscular skeletal exam to them, either pri provide reassurance, right, or pursue work up with lab studies, neuroimaging or place appropriate referrals. Here's uh an algorithm for deciding when to get neuroimaging or lab work. Um This was uh from pediatrics in 2013. Um and starting at number four again, sorry, the the text is really small, but hopefully some of you have this in your printout. If there's a neuromotor development concern identified during routine screening, there is, but there's no concerning birth history and there hasn't been regression and physical exams otherwise normal, then you might continue to monitor closely if there's an abnormality and tone that's noted on, on exam that may prompt further work up. Um that can be started in the primary care setting. If there's um is hypertonicity, then uh you'd consider neuroimaging with a brain MRI and if a child is diffusely hypertonic, um then measuring AC K and T S H just starting out with that as a screen for a myopathy. Um at the same time referring um to for further work up, um, usually to a neuromuscular specialist. And, um, uh, I think at this point, placing both neurology and um PM and R referrals together works really well at our hospital in Oakland, our neuromuscular neurologist, Dr Fay, um, uh, takes the lead in sending a lot of the, um, work up for myopathies and other neuromuscular disorders. Um But if I'm seeing a two year old in clinic who's um standing or cruising up on their toes and they have some hyperlexia and staticity at the legs and they were born premature um with uh maybe had a little bit of intraventricular hemorrhage that was noted in the N U. Um Then I can make uh on uh on the head ultrasound, then I can make a clinical diagnosis of spastic diplegic cerebral palsy. Um and I might not get um imaging because uh at that age, we still need um uh to get the MRI under general anesthesia, which has its own risks and um had proving that they have paraventricular loco mole and MRI doesn't really change our management. Um On the other hand, if they have hypertonicity, that's either new or with a, a normal birth history, then an MRI would be important to find the cause of their hypertonicity. And um uh again, if there is concern for a myopathy, then I would uh if not already placed. I would refer to our neuromuscular specialist for further work up. We used to do E M G S um on kids who were referred for concern for myopathy um ahead of doing a muscle biopsy for confirmation. But um nowadays, with the ability to diagnose a lot of these um myopathies and neuromuscular disorders with just genetic testing, um we rarely do E M G S um to diagnose myopathy. We still do use it um for uh E M G and nerve conduction studies to evaluate for neuropathies. Um Now moving on to the physical exam. So when a child presents to a clinic with concern for mood or delay, what are we looking for on physical exam? Obviously, infants and young Children can't follow a a formal manual motor exam. Typically by around age six, they can reliably follow it. Um And some kids can, can at like three or four years old if they're very mature. Um But most of our exam is done by looking at how much they're moving and how um and how the quality of their movements, we observe their head and trunk control as they're being held by the caregiver and in clinic. And are they looking at faces or looking around the room? What are their eye movements look like? Do they have any tosis or incomplete eye closure? What does their cry sound like? Is it software horse which may indicate weakness and if they're crying and the parent hands them a bottle. Do they reach for the bottle? And how are they holding it? And does their sucking look coordinated? Um, and when they reach for toys, how do, how are they grasping? Um, the toys? Do they have any like dystonic posturing or flaring? That may indicate weakness? Um, and how do they transition from pine to rolling, to pushing up with arms to being on quadruped and to standing? And what do their feet look like when they're actually bearing weight? Do they collapse immediately or are they up on their toes? Are they hyperextending at their knees or crouching a lot at the hips? And in examining their arms and legs, we look at range of motion and muscle bulk and um contractures or skin dimpling in infants can be indicators of poor fetal development, which can be seen in infants with a lot of neuromuscular disorders or those with arthrogryposis and then evaluating tone and deep tendon reflexes is really important. Um because hypertonicity or hyperlexia, as you all know, um can indicate an upper motor neuron process where hyper hypotonia or hyperlexia can be seen in many genetic disorders as well as neuromuscular disorders. Um and uh doctor no and her talk um will go over more of the spasticity evaluation in particular. Um But um in older infants, we're also looking for persistent primitive reflexes like the more A T N R um which should normally extinguish by 4 to 6 months of age. I didn't include this in my talk for this year. I talked about it a little bit last year. Um But for cerebral palsy, specifically, there is a physical assessment called the Pre General Movements Assessment that's done early in infancy um particularly in the uh for premature babies and babies with uh hypoxic ischemic encephalopathy um for early diagnosis of cerebral palsy. And we uh you know, traditionally don't formally diagnose cerebral palsy until about two years of age. But in recent years, there's been an emphasis to diagnose early or at least diagnosed with uh uh make a diagnosis of being at high risk of developing cerebral palsy so that we can get these Children hooked into services um in early intervention sooner and also reduce family stress of not knowing. Um But in the clinic, uh these are some of the red flags that we're looking for in the history or in clinical exam rolling before three months is usually abnormal and most of the time due to hypertonicity or posturing that throws them into rolling at four months. A child who lacks head control, who demonstrates scissoring at the legs, um indicating some add after muscles tosic would be worrisome at six months. The um persistence of perimeter for reflexes again, um which should have integrated and disappeared by then as a concerning sign and then sitting or w sitting can be a sign of poor tranquil control. Um commando crawling or inability to come up, the quadruped on the arms and knees may indicate plasticity of the legs and then a hitching type of crawl can indicate hemiparesis weakness or abnormal tone on one side of the body. Some other red flags from physical exam and diagnostics are listed here in muscular dystrophies. You generally see C K levels that are more than three times the normal values. Um, physical exam findings that are concerning, uh, for uh motor neuron disorders um may include physics um which are seen in conditions like spinal muscular atrophy and um facial dysmorphism, organomegaly and cardiac abnormalities. You're going to be uh worried about some glycogen storage disease or possibly and developmental regression with loss of motor milestones is um an obvious red flag that would warrant neuroimaging and genetic testing for neurodegenerative conditions like rats or liquidy ph and loss loss of motor function with minor acute illnesses may um raise suspicion for mitochondrial disorder. But what if you're seeing an 18 month old in clinic who's not yet walking? They may or may not have had some fine motor and or a speech delay, but their exam is normal with no red flags that we mentioned. Um you might ask yourself or the parent may ask you what's the chance that there's an underlying abnormality? So there's not a lot of studies that really looked at this question um in a very systematic manner, but probably the most relevant prospective population based study to date was one that was done in England in the 19 eighties. And in this study, they prospectively followed Children in the county called Oxfordshire, which is a little bit outside of London, who at 18 months was still not walking independently um with walking independently defined as taking five or more unassisted steps. And they estimated having screened about 80% of the pediatric population in the county. And there were a little over 400 Children who were referred during a four year period, which accounted for about 1.6% of all 18 months old in that county at that time. And about 30% of them had a known diagnosis with the majority of them being cerebral palsy. And in those that had um uh in those who didn't have uh a previous uh diagnosis that explained the delay in walking. The incidence of newly diagnosed neurological abnormality was about 7% which um mild forms of cerebral palsy made up for about a third of these Children. And they didn't um elaborate on the other neurological abnormalities or diagnosis that accounted for the two thirds um for the other two thirds. But if they had a normal neurological exam or a diagnostic eval and diagnosed with idiopathic late walking, over 90% of these Children eventually achieved independent walking by two years of the age or about six months after they started taking some steps. Um I included this slide to give an idea of what we see in terms of average age for uh achieving independent ambulation in Children who have known underlying conditions for Children with plastic diplegic C P. Generally, if they achieve sitting without support by two years of age, then they have a good chance of walking by 3 to 5 years of age. And in many cases requiring uh ankle, foot orthosis, um or ankle braces. Um and depending on the degree of involvement may also need a, a walker to walk independently. But they can in, in uh those ways, um achieve independent ambulation and kids with muscular dystrophy, mean age for onset of independent walking ranges for 15 to 20 months across different studies and data sets. And in kids with down syndrome, most will have some gross motor delay um with mean age for cruising being around 18 months and walking independently around two years. And in Children with spin of if their mylo or functional level is L four where they have good hip flexion and knee extension, most can walk with the aid of a F Os and maybe a walker or four arm crutches. Um uh by you know, the the time they're about four years of age. But uh as they get older and put on more weight, many will lose community level ambulation though they may still be able to emulate short distances within the home. And if their level is, then they may have some in dole and um uh impaired a equal plan f reflection or absent a equal plan reflection. Um But they typically walk around two years with or without a F OS. Um though they might have some deviations and foot positioning and gate pattern. So walking is um such an automatic movement we do daily. But when you break it down, human gait is really complex. Um And it involves intricate interactions between the pelvis hips, knees, ankles, and involves a lot of highly coordinated cyclical series of movements. And I won't go into too much detail. Um But uh the gate cycle consists of two phases, the stance phase and swing phase. The stance phase accounts for 60% of the gate cycle and starts with the heel strike when your heel touches the floor and it ends with toe push off. And the swing phase occupies the remaining 40% of the cycle and begins after toe off where you swing your leg forward and ends when the heel strikes the ground again to start another cycle. It's likened to um vaulting over an inverted pendulum where one leg is bearing weight while you're simultaneously swinging the contralateral leg in a synchronized fashion. And there's not a lot of vertical movement right at the hips or sway at the trunk. Um And the stride or step lengths are regular and controlled when a child first starts to walk. Though, you see short, um quick rigid steps, lots of trunk oscillations and vertical, hip displace displacements with the toddler having uh a wide base of support and carrying their arms up in high guard position as they're trying to keep their balance, their hips and knees remain slightly flexed and they'll lift their foot high above the ground during swing and then make flat footed contact when their foot comes down to the ground instead of doing a heel strike, typical of a mature gate. And it's around two years of age that you start to develop the heel to a pattern. Um And around age 3 to 5 is when you start to develop an arch and the foot. I know, um I think Doctor Lenton covered the topic of in towing and out towing in this morning's lecture. So I won't go into much detail here, but we'll review that. Um, it's typical to have some Genova or bowing up the legs initially, then an 18 month or about six months after the onset of uh independent walking, the knees become straighter and less bod and they're able to stand more upright and able to extend their hips more than previously, stop having um, excessive movement of their hips out to the side when they walk and around three years of age. Um, you might see the alignment change to appear more knock kneed and the rotation of the bone in the upper leg continues to be twisted somewhat with some femoral anti version or tibial torsion. But by age four, the walking pattern is mostly mature in most kids. And by seven years of age, the alignment tends to also normalize um where the legs are mostly straight with some bowing or not need alignment in some kids and mild out towing where you might see two toes out when you look from behind the heel. Um One of the more common things we see in Children referred for gate assessment to our clinic is pronation where you see collapse of the medial part of the foot and pronation actually is comprised of three main components um or what we call tri planar movement of the foot and in um which are one calcaneal valgus, two collapse of the medial arch and 34 ft abduction, turning in and flat food is typical in infants and young Children, as we mentioned earlier, that are just don't really start to develop until about 3 to 5 years of age, but excessive pronation can lead to some delay in deficits in walking. So we see this most commonly in Children who have hypotonia for whatever underlying reason. Um And these Children also present often with ligamental laxity and have increased range of motion at the ankle. It's common to see um these Children be mildly delayed in pulling to stand or cruise or they may reach those milestones on time, but then may plateau and not progress to taking independent steps as quickly as expected or they might take steps. But they continue to fall very frequently. Um And the reason for this might be multifactorial, um including, you know, they may also have some decreased postural control or proprioception impairment. Um uh that will continue to, you know, develop and progress uh in a good way over time. But excessive pronation um causing an unstable base of support can be a a significant factor that may be limiting their um pro timely progression. So what do we do for this? Well, if a child has delayed walking, they've probably been referred to physical therapy and the physical therapist will be working with them doing play based activities to try to facilitate movements that would strengthen the foot and ankle muscles as well as the larger stabilizing muscles, um uh including the quads and hip curdle muscles so that the whole chain can work more efficiently. But when there's excessive pronation, there's a role for bracing. And in most cases, an S M O or super malar orthosis, which is the shorter brace that comes right above the ankle is enough. Um S M OS um uh help with guiding the heel into proper alignment. Um So if their calculus is an E version, it stabilizes to a more neutral position, it also lifts and supports the arch um and keeps the tone in alignment with the rest of the foot. And I've heard arguments against using an S M O on a child who has just mild gross motor delay Um And uh one of the arguments I often hear is that racing them would not allow free movement of their foot and ankle. So it prevents muscle development or natural strengthening. Um And I, I've talked to a lot of uh veteran physical therapists, some who are in this room. Um And the general approach uh is that if pronation is severe enough that there's e version of the heel, there is benefit to supporting their foot with an S M O. And from my perspective, um I think there's two main reasons. One is that when you optimize the position of the foot, it allows for better timing and strength of the muscle activation so that you're actually working the muscle more efficiently. And in hypertonic muscles, um the muscle spindles aren't pulled as taught. So it tends to require a greater stretch of the muscle before they're activated. And this delays the signals to the brain that synapse on the alpha motor neurons that tell the the muscles to contract. So this delay in muscle activation can appear um as weakness. But um when the the positioning is in an optimal alignment, then the timing of the contraction can become more typical and you can get stronger activation of the, the weak muscle. And um by having your foot in proper alignment, I think it also helps with properer development of the muscles higher up the chain, including your hip muscles. And the other reason is to um, to break, consider bracing is to support development of the foot and the ankle. Um, bracing doesn't fix the pronation, right? And I, I make this clear with the family, it only supports the foot and the ankle. But, um, and, and most kids with mild or even moderate hypotonia who, who, um, walk will, uh, eventually build strength enough so that we can wean them off of S M OS. Um, because their hyper pronation over time does improve. Um But if their feet is not supported and their ligaments get overstretched, the pronation can be become more difficult to correct as they grow. And you know, if they're, if they get older and then their bones then ossify in this pronated position, then they'll continue to pron into adulthood which can cause pain or easy fatigue. Um And another common g abnormality we see in a lot of, uh, we see a lot in our clinic is toe walking and we said earlier that classic toddler gate is flat footed, but tow walking or inter toe walking is something a lot of toddlers do and as a normal staging gate development, however, it is something that should resolve within a couple of years and it's really rare to see it past um, five years of Asian, typically developing Children, kids who tow walk most commonly present to our clinic. Um In the first 1 to 2 years after they start taking steps, families usually report concerns about the child having poor balance, frequent falls or not keeping up with kids. Their age and older Children might complain of muscle cramps, foot pain or fatigue with walking long distances and might be prone to ankle sprains or calluses at the balls of their feet. Causes of toe walking can be various. Um So in addition to the range of motion and musculoskeletal exam, again, we're doing a thorough neurologic exam to look for things like cerebral palsy, uh uh tethered spinal cord or uh muscular dystrophy, which are uh the other common um causes of toe walking and autism spectrum disorder is not a cause, but um does have a strong association with to walking due to sensory processing difference is likely. And if a child walked normally at first and then started to walking later, then it raises suspicion more for a neurological or neuromuscular process. But if it's an otherwise typically developing child with no other concerning exam findings, then we label it idiopathic toe walking. And um the majority of kids with idiopathic toe walking walk at a normal age and when directed to do so they can stand on their heels on the ground. Um As long as they haven't developed contractures or decreased range of motion and even when they walk, um they may be up on their toes and then intermittently might bring their heel down. Um and, and sometimes do a, a heel strike and then a toe off typical of a more uh uh normal gate. Um idiopathic toe walking was previously thought to be exclusively due to habit. But there's an association with differences in motor control, um sensory processing, sometimes vibration perception thresholds. And in a lot of cases, parents and families do report a a family history like, oh his father tow walked or a sibling tow walked when they were younger, long term natural history studies are limited. Um the most uh like I said, do resolve during grade school years and optimal treatment is not fully elucidated. Um But main goal of management is to maintain range of motion at the ankle so that kids don't develop planter reflection contractures that will make it harder or even impossible to walk with the heel down later on. Um simply queuing the child to walk on their heels with frequent reminders hasn't been shown to be effective. Even studies looking at P T and stretching exercises in these IOP paic toe walkers, um haven't proven to be very effective using A F Os to block the plant reflection and forcing them to bring their heels down works when they're wearing the A F Os. But as soon as they take them off, they tend to go right back up on their toes. So general rule of thumb, if they're younger and still have a lot of flexibility with their ankle, um able to be Dorsa past the neutral position. Um then we may just observe and if their toe walking is more mild. Um, but have they, they are developing some ankle tightness, then I often prescribe ankle stretching splints which are basically articulated or hinged A F OS that, um, with straps that you can pull on to adjust the Dorsa function degree. And I have them wear it for at least 2 to 3 hours a day when they're sedentary or sleeping to really get a good stretch on their achilles. Um So that their range doesn't get worse. If they're really high up on their toes or they start to develop restricted range, then I recommend daytime or walking A F OS that I have the child wear basically all the time when they're walking outside, like at school or park. Um And if they've developed decreased range of motion where we can't get them um to neutral position or above, then I recommend serial casting to improve the range past neutral. And then after serial casting, transition them to walking A F Os and Botox injection is typically not indicated in um, idiopathic toe walking where spasticity is absent. But if someone has severe contractures where I don't think they would tolerate the serial casting without Botox, then I might consider it. Um And then if they are older in age or if the contractions are really severe, then I refer to orthopedic surgery for surgical lengthening. Ok. And then lastly, I just wanted to throw this in here since it's a question we do get asked a lot, which is about using a baby walker. So we as pediatricians generally recommend against it, right? Because babies can, um, sometimes move really quickly in these things, risking injury, um from falls downstairs or even smaller steps that can sometimes result in serious injury like a head injury. But despite this, it remains really popular with parents and uh, there's a lot of commercial baby walkers on the market. I see a hand in the back. Oh. Oh, ok. Ok. Thank you. Um And um medical providers uh including physical therapists um have also discouraged you with the thought that walker encourages walking with abnormal like learning, um abnormal walking patterns, like forward leaning trunk and toe walking and doesn't strengthen the core and hip muscles enough so that the child may learn to walk in this abnormal way and it might delay development of a normal gate pattern. And past studies that looked at this, which were mostly observational studies were really inconclusive on harm versus benefit. Um There was a study that looked um at whether there were differences in gate mechanics though between these toddlers who use baby walkers and those who didn't and whether there was a difference. And when uh the timing they achieved independent walking, it was a small study with only 16 toddlers in each group. But it was interesting because they actually used instrumental gate analysis to really look at differences in gate kinematics. They um recruited participants by asking parents at infants. Um 6 to 9 month well, child visit about their opinion, the parents opinion on baby walker use. And if, if they were interested in using a baby walker, they were randomized to the baby walker group. And these were all babies born full term with no complications and with growth, motor gross motor development score about um uh above 10 percentile on the um AMES or Alberta infant motor scale parents in the baby walker group documented the amount of time. Um The the be spent uh in the walker which ranged from like 45 minutes, usually to um an hour and a half or two hours a day. And uh first measurement of the gate like the gate analysis was done on the week that they acquired um uh independent uh walking, which was more than five steps. And um they did these measurements monthly until six months after they started walking on their own. And they found that there was no difference in the age of independent gate acquisition between the two groups. They did find difference in the gate kinematics where the baby walker group had lower gate speed, um and longer duration and stance and swing as well as some differences in in knee and hip movements. Um But these differences disappeared in the months following gate acquisition. Um So use of baby walker may not be harmful or at least have, may not have long lasting effects on gross motor development of otherwise typically developing Children. But I still recommend against it due to the risk of um inadvertent injuries. So that was a uh a lot of slides um for me to uh make these very simple, take home points. Um for purposes, Children should achieve independent walking by 18 months of age. But if there is global delay or any abnormal physical exam, findings refer early toddler gate uh evolves um but should develop a heel to toe gate around 2 to 3 years and delayed walking or abnormal gate pattern with excessive pronation or toe walking present. Then I would consider bracing. Thank you.