Leg Stress Fractures.

(Distilled knowledge from the internet and books)



Runners often suffer from overuse injuries or repetitive stress injuries. These include shin splints, compartment syndrome, stress fractures, stress reactions, tendonitis, meniscal tears, ITB Friction syndrome, and so on.

Stress fractures are quite serious things and need rest from running from 3 to 6 months and up to a year. It is worth making a note of other lower leg problems first.


Medial Tibia Stress Syndrome and Shin Splints
This is a soft tissue, or muscle problem and the term Shin splints and MTSS are often used to describe similar problems

Signs and symptoms:
Tenderness is usually found between 3–12 centimeters above the tip of the medial malleolus at the posterio-medial aspect of the tibia.

Causes can be linked to:
Running with the weight too far forward Striking the ground with the first third of the foot Over-striding Overpronation Shoes too tight around the toes Inflexible shoes Weak arches may be present Tight calf muscles stress the shin structures Calf muscles much stronger than the shin muscle Which, tighten and pull on the shin muscles Beginner runners are very susceptible Overtraining is its trademark; especially Increasing mileage too quickly Running on hard surfaces Too much speed work, too early, on hard surfaces

The whole body is connected and something out of line affects something else somewhere else – so weak torso can create problems in a runners foot. For example, muscle imbalance such as weakness in the pelvic stabilisers which allows the hip to drop and the knee to drift inward during stance causes the foot/ankle to pronate.

Research has shown simple exercises directed at pelvic stability can help correct common mechanical faults which may lead to injury. Avoidable factors include training errors (too much, too soon, too often), and improper footwear and training surfaces. Surprisingly, once symptoms develop, softer running surfaces often aggravate symptoms of MTSS

Refer to www.roadracestatistics.org.uk for a better description of shin splints



Compartment Syndrome
Compartment syndrome can occur if there is increased pressure within a confined space in the body. It usually occurs in areas of the body known as fascial compartments which are found around muscles. There are four fascial compartments in the leg below the knee. The most common compartment syndrome that occurs affects the anterior (front) fascial compartment below the knee.

It is usually a separate injury to a limb that causes compartment syndrome and this can be almost any injury. It can even occur after vigorous exercise. Compartment syndrome usually comes on fairly quickly after injury (within 48 hours). However, a chronic compartment syndrome is also possible.

The initial injury usually causes swelling of the muscles and tissues within the fascial compartment of the limb. This causes the pressure within the compartment to rise. As time progresses, and as the degree of pressure in the fascial compartment increases, blood flow to the muscles in the compartment reduces. This lack of blood flow (called ischaemia) means that oxygen is not delivered effectively to the muscles and muscle damage begins to occur. As muscle damage occurs, muscle cells start to produce chemicals which can further increase swelling and pressure within the compartment. A vicious circle can be set up. Nerves within the compartment can also be compressed and damaged

A fracture (a break in a bone) is probably the most common injury that can lead to compartment syndrome. Compartment syndrome can also occur due to:

  • Vigorous exercise
  • Penetrating injury such as stabbings or gun shot wounds.
  • Crush injury.
  • Burns.
  • Snake bites.
  • Bleeding from an injured blood vessel.
  • Plaster casts that are fitted too tightly.
  • Intravenous drugs (usually given via a drip into a vein) that inadvertently leak inside the arm around the vein.
  • The main symptom of compartment syndrome is pain. Pain usually occurs even at rest and may also be worse on movement. Pain is likely to occur after any injury but in compartment syndrome, the pain tends to be severe and out of proportion to the injury. For example, pain usually improves when a fracture (a broken bone) is immobilised in a plaster cast or with a splint. In compartment syndrome, pain typically increases despite immobilisation of a fracture. Nerve damage due to the compartment syndrome may also make pain worse. You may feel a burning sensation or tightness around the affected area.

    Pins and needles can also occur in the arm or leg affected by compartment syndrome and you may have reduced sensation when the skin on the affected limb is touched. An affected limb may also be pale, may feel cold and may feel tense or hard. As compartment syndrome progresses, you may experience reduced strength in the affected arm or leg and sometimes paralysis of the affected limb can occur

    Symptoms of anterior compartment syndrome include:

  • A sharp pain in the muscle on the outside of the lower leg, usually the result of a direct blow.
  • Weakness when trying to pull the foot upwards against resistance.
  • Swelling and tenderness over the tibialis anterior muscle.
  • Pain when the foot and toes are bent downwards
  • Compartment syndromes usually produce pain with palpation only if the compartmental pressure is elevated, such as right after the activity, while shin splints likely are to be tender to palpation long after activity has ceased. Shin splints produce pain with stretching and manual resistance (resisted dorsiflexion). Compartment syndrome is not as likely to be painful with either manual resistance or stretching because neither of these manoeuvres increases the intracompartmental pressure. If paresthesia is present, compartment syndrome should be suspected because this is a symptom of nerve involvement and there is no nerve pathology in shin splints



    Tendonitis
    If the problem is not a stress fracture but rather inflammation of the tendons of the shin muscles (tendonitis), the pain is often quite diffuse, running up and down the lower part of the leg along the tibia. It is true that tendonitis can mimic a stress fracture by producing crescendo pain, but tendonitis discomfort is often less localised than stress-fracture pain and usually can’t be produced simply by tapping on the bone. With shin tendonitis, there is usually none of the numbness associated with compartment syndromes. Naturally, if your shin-area pain is a continuing problem, you should seek the advice of a sports-medicine doctor.



    Stress Fractures

    Introduction
    What is a Stress Fracture?
    A stress fracture is a crack that does not go completely through the bone (these were first noticed in solders who marched too far, too hard or too often), sometimes described as a hairline fracture. They typically occur in the weight bearing bones of the lower leg (tibia) and foot (metatarsals).

    The injury is caused mainly by (unusual) repeated stresses on the bone, and if this stress is greater than the strength of the bone then it will fracture or break. During weight-bearing activity (such as running), compressive forces are placed through the tibia. In addition, several muscles attach to the tibia, so that when they contract, a pulling force is exerted on the bone. When these forces are excessive, or too repetitive, and beyond what the bone can withstand, bony damage can gradually occur. This initially results in a bony stress reaction, however, with continued damage may progress to a tibia stress fracture.

    Bone weakness can be an issue – where one athlete suffers from stress fractures another will be OK because of different bone strengths. They are different from other fractures because they are not caused by a single impact on the bone, but develop gradually.

    Tibia stress fractures can be confused with other lower leg problems such as Shin Splints (Medial Tibia Stress Syndrome (MTSS)), compartment syndrome and other leg problems. Stress fractures are not as common as the other lower leg injuries. Some confusion occurs particularly in the initial stages of the injury.

    Symptoms
    Stress fractures like all injuries are best diagnosed by a doctor. They usually have few symptoms:

  • Generalised area of pain and tenderness associated with weight bearing (walking, running etc)
  • A stress fracture pain is likely to be a continuous pain and restricted to one spot (you can pin point where the pain is)
  • You might feel pain when you put pressure on the shin
  • When running, a stress fracture in the leg or foot will cause severe pain at the beginning of the run, moderate pain in the middle of the run, and severe pain at the end and after the run
  • Pain is likely to be in the lower third of the shin and doesn’t subside when you stop running
  • Gradual onset of localized pain at the inner aspect of the shin bone
  • The pain is often sharp or acute in nature and typically increases with impact activity and decreases with rest. Occasionally pain may be felt with rest or even at night. In severe cases, walking may be enough to aggravate symptoms
  • Tenderness on firmly touching the inner aspect of the shin bone
  • Pain in only one leg could be an indication of a stress fracture or other injury rather than some overuse injuries such as shin splints
  • The pain usually starts out over a large area along the shin bone, and is mainly noticed after a hard training session or race, or the morning after a long or difficult workout
  • X Rays usually do not show a stress fracture until they are nearly healed; a CT scan, MRI or 3 phase bone scan might be more effective. These however are quite expensive
  • You can still be run with a stress fracture – there are example of people winning Olympic medals with them, however you are dong more damage if you do.
  • Some runners who suffer from other overuse injuries are more prone to stress fractures
  • Shin splints can cause stress fractures, shin splints occur when the muscles pull away from their attachment site along the inside of the tibia, left untreated, the muscles will continue to pull, and this may cause a crack to form in the bone. The pain will progress to the point where it is noticed more during the run, and become focused on a smaller area of the bone
  • Occasionally, a tibia stress fracture may present as calf pain rather than shin pain

  • Stress Fracture vs. Shin Splints
    It is worth showing this here because the 2 can be confused.
    Stress FractureShin Splints
    Stop all running, avoid all high impact sports for the legs Reduce running, RICE, Anti-inflammatory
    Localised pain, in line parallel to the ground when stood up, generally in lower 1/3 or leg General pain, longitudinal pain (up-down).
    Tends to be one leg Tends to be both legs
    Overuse Injury affecting bone Overuse Injury affecting muscle
    Shooting pain all the way through the run that doesn’t die away afterwards shooting aching pain at start of run easing during the run, stopping after the run finishes
    Can be painful walking, stretching, climbing stairs No pain walking, stretching, climbing stairs
    Hard nodule might appear on the bone at the fractured area

    Causes
    A stress fracture of the tibia is an overuse injury that typically develops gradually over time due to excessive weight bearing activity such as running, sprinting or jumping. It often occurs following a recent increase in activity or change in training conditions. If too much stress is placed on a bone then it is likely to fracture, repeated small stresses on the bone added together over time overwhelm its ability to repair, or look after itself and a fracture occurs

    There are several factors that may contribute to the development of this condition. These need to be assessed and corrected with direction from a physiotherapist. Some of these factors include:

  • Too much running or inappropriate running
  • Returning to Running
  • Muscle weakness or fatigue
  • Beginning running
  • Increasing mileage too quickly
  • Running style (or biomechanics)
  • Running Surface
  • Running shoes
  • Weak bones and diet
  • Weight
  • Hormones
  • Running through ‘shin splint’ pain
  • Inadequate flexibility (calf muscle, ankle joint)
  • Leg length discrepancies

  • Too much running or inappropriate running
    This is the obvious cause that the more you run, the more stress the bone suffers and the more chance of a stress fracture you have. While I am not saying to become a couch potato, they have very few incidences of stress fractures! Running on an inappropriate surface for the distance impacts the shin bone harder than a good surface – limit running on concrete.

    Too much running - Muscle Fatigue
    With tired muscles their shock absorbing ability reduces – so the bones have to absorb the stress increasing the risk of fractures. Muscle strengthening can help reduce stress fractures and support the bones if the do occur aiding healing.

    Returning to Running / Beginning running / Increasing mileage too quickly
    Bones repair themselves and remodel themselves over time to cope with the stresses they are under. After a break from running or going from sedentary person to runner too quickly and the bones do not have time to get stronger, and the repeated running impact can cause problems. Similarly if you increase the miles you run too quickly the bones don’t get time to strengthen

    Poor biomechanics
    All lower leg pains can be attributed in some form to the way you run. With stress fractures this is how hard you land with each stride – the harder you land, the more stress your bones take. The less flexible your legs, the more stress on your bones and so on.

    Running Surface
    Concrete is six times harder on your legs than tarmac which is three or more times worse than packed dirt trails. Grass and muddy trails are still softer. The harder the surface the harder it hits your shin bones.

    Running shoes
    The cushioning in your running shoes break down over time – so a new pair will take some of the impact each stride. A worn out pair will not be as effective. ‘Racing flats’ have reduced cushioning to reduce weight and this increases impact on the legs. Too many miles in either type of shoe can cause problems. Similarly minimalist ‘barefoot’ running shoes have very little cushioning either.

    Weak bones and diet
    Some people suffer stress fractures because of their diet, particularly calcium poor diets. Calcium poor diets cause osteoporosis later in life. Females tend to be more prone because of the “Female Athlete Triad”, a mix of osteoporosis, amenorrhea (absent or infrequent periods) and eating disorders that occur together. Eating disorders often cause the sufferer to restrict calcium rich dairy products (cheese is often seen as bad because of the fat content), Amenorrhea can limit the body’s ability to process the calcium used to strengthen bones. Children who need minerals for growth and to run may also be put at risk – a reason why very few long distance races accept children (anything over 5km)

    If your diet is short on calcium, your body will steal the mineral from your bones, making them vulnerable to breaking. Magnesium is another important mineral for bone strength. Remember that the bones are always growing and so will always need nutrients to grow strong.

    Overweight people obviously exert more forces on their body as they move and since stress fractures are caused by more stress on the bone than they can take, weight has an impact. Similarly being underweight can have an effect too – there are fewer energy reserves in the body allowing the muscles to get tired quicker, and few nutrients free in the body to repair running damages

    Hormones
    Low concentrations of testosterone or oestrogen may increase the risk of stress fracture.

    Running through shin splint pain
    Pain is a way for you to recognise that something isn’t quite right. Shin splints can cause stress fractures by the shin muscles pulling on the bone and so causing the damage that way. A secondary effect of keeping running through the pain is that your running style changes and this can affect how heavily you land on the ground – which can increase the impact and so cause stress fractures.

    Flexibility
    With any running, inflexible muscles cause other muscles to over work, tiring them and tired muscles can cause problems such as shin splints or stress fractures. Tired shin muscles don’t expand and contract and put more direct pressure onto the shin bone and this can cause stress fractures

    Leg length imbalance
    Not much you can do here apart from insoles but with a longer leg the stresses are not balanced, making one leg more stressed and working harder than the other


    Cure
    Bones are always growing and will repair themselves over time – but you have to give them the time to repair themselves. Typically this means no high impact sports for 3 months to a year. Reducing the amount of walking you do too, though other exercises such as cycling and swimming are good to keep fitness levels high.

    As always prevention is the best cure – but often you can’t live your life trying to prevent things that might never even happen (for example, you could prevent being in a car crash by never going in a car – impractical!). Prevention is good if you have suffered from them before. Sensible tips though are to increase mileage slowly (and this includes after returning from injury), stretch well before or after a run, warm up before a run, make sure your shoes are suitable – even have two pairs of shoes to alternate and let the cushioning recover and try to run with a ‘good form’ (also a good tip because one pair can air and so smell less). Last one is most important for impatient runners – heal before you return to running otherwise the injury will get worse again. You are reading about stress fractures – perhaps it is too late to learn about prevention, just how to cure them?

  • With a suspected stress fracture, see your doctor who might be able to get it scanned to confirm this and can check if it is healing.
  • Stop running and rest the area for six to eight weeks, or longer. You can do lower impact exercise like walking, swimming, deep water running, and weight training. If you don't rest your shins enough, the area may never heal properly. Once the pain begins to subside, you can start to work out. Just be sure to gradually build up time, distance, and intensity. If the symptoms return then start the healing process again
  • Consider running again when there is no pain when you press the affected area
  • While you are resting figure out why you got a stress fracture, recover and strengthen your muscles ready to come back stronger and faster
  • Crutches can take the weight off the bone and protect it allowing it to heal faster
  • Did I mention rest to let the bones heal? You cannot do much rehabilitation on a bone like you can with muscle injuries so pure rest really.
  • Patients should also perform pain-free flexibility and strengthening exercises as part of their rehabilitation to ensure an optimal outcome. Alternative exercises placing minimal weight bearing forces through the affected bone should be performed to maintain fitness such as swimming, cycling and water running. The treating physiotherapist can advise which exercises are most appropriate for the patient and when they should be commenced.
    A review with a podiatrist may be required for the prescription of orthotics and footwear advice, particularly in those patients whose foot posture and lower limb biomechanics have contributed to the development of the condition.

    Once you can press the area of the fracture without pain then you can resume training slowly, so long as the activities do not cause pain. While the bone may feel healed and not hurt during daily activity, the process of bone remodelling may take place for many months after the injury feels healed, and incidences of re-fracturing the bone is still at significant risk. Activities such as running or sports that place additional stress on the bone should only gradually be resumed. One general rule is to not increase the volume of training by more than 10 percent from one week to the next.

    Muscle strength training can help to support the bones – muscles are the legs shock absorbers too

    When you return to running, start very gently and always warm up adequately. This will bring blood and oxygen to the injured area and also lubricate the joints. Wear training shoes with good cushioning and continue with stretching. If you feel any pain at all stop, rest a few days until the pain has gone completely. If all is going well then building up running. Gradually build up the distance that you run per day over the period of ten weeks with an increase of about 10% a week. It is also important to have rest days between each running day for the first couple of weeks.

    Last point on curess:
    With severe stress fractures, surgery may be needed for proper healing. The procedure may involve pinning the fracture site, and rehabilitation can take up to a half year.


    Physiotherapy
    Physiotherapy treatment for patients with this condition is vital in to hasten healing, ensure an optimal outcome and prevent injury recurrence. Treatment may comprise:

  • soft tissue massage (particularly to the calf muscles)
  • joint mobilization (particularly to the ankle)
  • electrotherapy (e.g. ultrasound)
  • dry needling
  • the use of crutches
  • the use of an appropriate brace
  • activity modification advice
  • arch support taping
  • biomechanical correction
  • exercises to improve strength, balance and flexibility
  • education
  • a gradual return to activity plan
  • correct footwear advice
  • Immobilising the leg
  • Prevention
    With any injury prevention the best way is to figure out why and how you got injured. Here is another example, say you ran into a wall and broke your nose, you then know that running into walls breaks noses – and so to avoid breaking a nose you don’t run into the wall. Same with running, if running in old shoes, for 30 miles on concrete gives you stress fractures then the obvious solution is to not do that – but like this example shows there are many factors that can upset the bodies balance and cause a problem (shoes, running surface, distance, speed…) while you are recovering you can try to work out which bit went wrong.

    One method of avoiding stress fractures is to add more stress to the bones. Though this may seem counter-intuitive (because stress fractures are caused by too much stress on the bone), moderate stress applied to the bone in a controlled manner can strengthen the bone and make it less susceptible to a stress fracture. Remembering how the bones grow – they will grow stronger if they are required to be stronger.

    An easy way to do this is to follow the runner's rule of increasing distance by no more than 10 percent per week. This allows the bones to adapt to the added stress so they are able to withstand greater stress in the future.

    Strengthening exercises also help build muscle strength in the legs. Strengthening these muscles (calf, shin, thigh….) will prevent them from becoming fatigued quickly, allowing them to act like shock absorbers for longer. Stronger muscles allow you to have a better running form for longer and so maintain a lighter footstep.

    Running shoe cushioning breaks down over time and stops being effective. Generally shoes should be replaced every 500 miles depending on the runner. There are resources online that show you haw to identify worn out cushioning on trainers.

    During exercise that applies more stress to the bones, it may help to increase calcium and vitamin D intake. Monitor your diet and take action if you think that you are low with vitamin C or D

    Apart from the bone repair itself, developing the surrounding muscles can help too:
    Strengthening and conditioning the muscles of the lower leg will can help to prevent stress fractures. There are a number of specific strengthening exercises you can do for these muscles. Running cross country benefits from stronger lower leg muscles.

    Exercises
    To be tried so long as there is no increase in symptoms or pain:

    Sitting exercises
    Repeat these repetitions 10 to 15 times, rest and do 3 sets:
    Place, and keep the feet flat on the floor, lift the toes. Put some weight on the toes to increase the strengthening
    Place the feet flat on the floor and raise the heel, hold for a count of 1 and lower
    Place the feet flat on the floor and raise the ball of the foot, hold for a count of 1 and lower
    Put the foot in the air and draw out the letters of the alphabet with the big toe of each foot
    Sit on a high chair or table and feet dangling in the air, suspend a weight from your foot and raise and lower this weight with the foot
    Use a resistance band (elastic band) held at one end (for example, round the leg of some furniture), sit on the floor and stretch the band round a foot, Move the foot forwards and backwards and side to side against the bands resistance.

    Lying down exercises
    10 to 15 repetitions and 3 sets of them,
    Lie on your back and move the foot in a controlled way all the way ‘up’ and all the way ‘down’
    Lie on your back and rotate the feet clockwise and anticlockwise pivoting around your leg bones

    Standing Exercises
    Again, 10 to 15 repetitions and 3 sets of them:
    Raise yourself up and down onto your toes (tip toes). Make this harder by holding weights in your hands or in a backpack
    Raise yourself up and down onto your toes (tip toes). Make this harder by doing this while standing on a step and letting your heel lower down under the step to stretch the calf
    With socks off, gather up a towel that is flat on the floor, using only the toes.
    Pick up marbles using the toes

    Walking exercises
    Gentle walking including some of:
    Walking down steep hills.
    Walking on toes.
    Walking on heels.
    Walking with feet turned inward and outward.


    Gadgets
    I love gadgets,,, These might be helpful depending on the severity of the shin splint:

  • Crutches
  • Ice packs or Heat Packs
  • Massage Balls or Foam Rollers (for self massage)
  • Wobbleboards (for balance exercises)



  • Barefoot running

    There is a movement towards barefoot running and this is reputed to cure every runner’s injury problems because “barefoot running is how we were intended to run” – true but we were meant to kill our own food for example. The butchers shop is progress with killing food and preparing meat for us; similarly running shoes could be progress with running. ‘Barefoot running is how we are meant to run’ but we were not designed to run on concrete or tarmac (asphalt).

    Barefoot runners don’t say a lot about stress fractures – only a lot of good things, they do go on (and on, and on) about the benefits to soft muscle damage and barefoot running benefits. Barefoot running is basically a rubber sole strapped to the feet with no cushioning or support.

    The lack of cushioning can increase the impact damage caused with each step and this can overload the bone and produce a stress fracture. This can be particularly noticeable if you are a ‘heel striker’, with no shock absorbing from the foot the stress goes straight up into the shin bones. Having no support in the shoe and the metatarsals are less protected leading to possible fractures after years of protection with trainers

    What the barefoot runners say though is that you should take time to retrain your legs to run in a more efficient and less stressed way – starting training again with 1 to 2 mile runs in the shoes, and to avoid very long runs such as the marathon (I have anecdotal stories of distance runners with barefoot shoes who then end up with problems). Over time they claim that you shift your runnign style from heal striking to forefoot striking, in my experience this does happen - mainly because standing on a stone directly with the heel hurts.




    Now as a complete aside, here is something I read while I was looking at this:

    Dinosaurs
    Allosaurus fragilis was found to have the most stress fractures of any dinosaur examined in a 2001 study.

    In 2001, Bruce Rothschild and other paleontologists published a study examining evidence for stress fractures in theropod dinosaurs and analyzed the implications such injuries would have for reconstructing their behavior. Since stress fractures are due to repeated events they are probably caused by expressions of regular behaviour rather than chance trauma. The researchers paid special attention to evidence of injuries to the hand since dinosaurs' hind feet would be more prone to injuries received while running or migrating. Hand injuries, meanwhile, were more likely to be caused by struggling prey. Stress fractures in dinosaur bones can be identified by looking for bulges on the shafts of bones that face toward the front of the animal. When x-rayed, these bulges often show lines of clear space where the x-rays have a harder time travelling through the bone. Rothschild and the other researchers noted that this "zone of attenuation" seen under the x-ray typically cannot be seen with the naked eye.

    The researchers described theropod phalanges as being "pathognomonic" for stress fractures, this means they are "characteristic and unequivocal diagnostically." Rothschild and the other researchers examined and dismissed other kinds of injury and sickness as causes of the lesions they found on the dinosaurs' bones. Lesions left by stress fractures can be distinguished from osteomyelitis without difficulty because of a lack of bone destruction in stress fracture lesions. They can be distinguished from benign bone tumours like osteoid osteoma by the lack of a sclerotic perimeter. No disturbance of the internal bony architecture of the sort caused by malignant bone tumours was encountered among the stress fracture candidates. No evidence of metabolic disorders like hyperparathyroidism or hyperthyroidism was found in the specimens, either.

    After examining the bones of many kinds of dinosaur the researchers noted that Allosaurus had a significantly greater number of bulges on the shafts of its hand and foot bones than the tyrannosaur Albertosaurus, or the ostrich dinosaurs Ornithomimus and Archaeornithomimus. Most of the stress fractures observed along the lengths of Allosaurus toe bones were confined to the ends closest to the hind foot, but were spread across all three major digits in "statistically indistinguishable" numbers. Since the lower end of the third metatarsal would contacted the ground first while a theropod was running it would have borne the most stress and should be most predisposed to suffer stress factors. The lack of such a bias in the examined fossils indicates an origin for the stress fractures from a source other than running. The authors conclude that these fractures occurred during interaction with prey. They suggest that such injuries could occur as a result of the theropod trying to hold struggling prey with its feet. The presence of stress fractures provide evidence for very active predation-based feeding rather than scavenging diets.






    [sources: wikipedia.org, physioadvisor.com.au, commonsportsinjuries.com, copacabanarunners.net, fitsugar.com, genufix.com, joemaller.com, sportsinjurybulletin.com,]