Articles in Category: Ergonomics

How To Correct Lower Back Pain

on Wednesday, 13 February 2013. Posted in Ergonomics, Chiropractic

Lower back pain is one of the leading financial burdens on the Australian public health purse. Costing the government and consumer billions of dollars per year.
This problem creates a massive negative impact on  peoples quality of life and their ability to participate in their normal daily routine.
According to one of the leading journals, 79.2% of Australians Suffer Lower Back Pain at some point in their life. (J manipulative Physiol Ther. 2004 May;27(4):238-44.)
We also know that

How to Lift Correctly

Written by Don Williams BSc, MChiro, ICSSD. on Wednesday, 23 September 2015. Posted in Ergonomics, Training and Performance

How to Lift Correctly

By Don Williams

B.Sc., M.Chiro., ICSSD., PG Dip. NMS Rehabilitation,

Cert. DNS.   Memb: CAA, FICS, CEA.

 

Effective lifting mechanics are an important aspect for our everyday lives. Patients often complain of low back pain and have not considered lifting or squatting technique as a factor in their complaint.

It really doesn’t matter whether you are lifting 100kg of weights on a bar or a tissue off the floor, correct form and technique is important.

 

One of the major problems which does catch people out is the magnification of force with loads in front of the body.

 

Low back mechanics are very complex, as demonstrated by the picture to the right (technical biomechanics are available in this link).   http://cnx.org/content/m42175/latest/?collection=col11406/latest

 

Figure 1

 

For lifting mechanics, we have a range of different lever classes and a stack of joints involved (ankles, knee, hips, spinal segments, shoulders elbows and wrists). But to put it in relatively simple terms, if you think of the low back as a pivot point, the lumbar extensor muscles are only 2-5 cm from the pivot point, when we lift, it is quite easy to have the load out in front 50cm. This can easily give us a magnification of force by 10 to 20 times the load. Essentially, this means that even though it is only 5kg you are lifting, the required compressive load in the lumbar extensors may be 100kgs. Wow!

 

Figure 2

 

 

Lifting with a straight back is not correct

There is a common misconception in the general population that we should lift with a straight back. (See diagram on right)

 

Many people interpret this as that the back is perpendicular to the ground. Lifting in this manner pushes the knees in front of the toes and necessitates lifting the heels off the ground to lift items at floor level. This increases load on the hips and knees, causes a lack of balance and a decreased lift capacity.

 

Figure 3

 

Don’t use you back

We certainly shouldn’t lift bending forward from the hips either.

As in the earlier explanation of lifting mechanics and lever arms, bending forward from the hips and lifting using the low back (like a crane) dramatically increases the likelihood of needing to see the team at Institute of Sports and Spines more often. We often hear complaints from people suggesting that using the hips and knees causes the knees to ache, commonly, when we assess the lifting mechanics with these people they are pushing too far forward with the knees causing increased load and pain, when we improve the mechanics, the knees feel much better in the squat position.

 

Figure 4 

 

Neutral Spine Position

When standing up straight and tall in good posture we have a lumbar lordosis and thoracic kyphosis. This “neutral” position of the spine is what we should strive to maintain when lifting and squatting. Effective use of this position should see the knees stay in line with or behind the toes, good balance capacity and effective use of the gluteal muscles as the main drive for the movement.

 

Figure 5

 

Additionally, good squatting technique should see alignment of the knees in the midline of the foot. In Prague school terms, this would be referred to as good “centration” of the joints. Poor alignment of the feet, knees and hips often contributes to pain on the inside of the knee or the outside of the hip (Trochanteric  bursitis)

 

Figure 6          Figure 7

    Poor Centration                                           Good Centration

 

Correct Squat (lifting) technique

At the bottom of the squat the lumbar lordosis should be maintained. Putting this into simple terms, this means that as you squat down, there will be a point at which the low back starts to “flatten out” and reverse the curve, this is the bottom of the safe lifting range and will be different from person to person. The knees should be in the midline of the foot and the knees should always be behind the toes. The feet should be straight or at maximum 15 degrees externally rotated (pointing out)

 

Figure 8

 

Squatting Drills

A great drill to assess your squat mechanics and to improve your function is to stand with your toes touching a box (or bedside table at home will work). It may be a good idea to put a chair behind you as some people will overbalance and fall backwards when they start this exercise. Slowly squat down, as if you were planning on sitting on the chair, and try to feel the point at which your back starts to move or flatten out. Try to ensure that your knees do not touch the box and that the knees stay in the midline of the feet. If you tend to collapse into the chair when you start this exercise, don’t lose heart, keep at it, reach out in front with the arm, the glut strength will build and this should become easier over a number of weeks. Try this 2-3 times per day, 10 reps each time for 6 -12 weeks until this pattern is easy and natural feeling.

 

Figure 9

 

Other Factors to consider

 

The last thing to mention in wrapping up is that when lifting load at work and around the home, weight is not the only factor which causes issues. The NIOSH guidelines are essentially internationally guidelines and equations which help to identify safe lifting practice and application in the workplace, the following links are very useful for those interested in learning more.

http://www.ergonomics.com.au/niosh.htm

http://www.cdc.gov/niosh/docs/2007-131/pdfs/2007-131.pdf

 

The following is a summary of the modifying factors for your consideration.

Increased weight. This is a no brainer, the heavier the load the harder it is to lift and to a degree, the more the risk. A good start point for safe working loads for 1 person are generally 15kg for females and 25kg for males.

Safe Lifting Zone. We tolerate and accommodate lifting loads between the knees and the shoulders fairly well, when the loads are above or below these points, the weight must be reduced.

Distance lifting (vertical or horizontal). Lifting an object from the knees to the shoulders repetitively is more difficult than just lifting from a bench at hip height to a bench 10cm higher.

Distance from the body. The further away from the body (out in front) the load is, the higher the relative load is on the back.

Repetitions or number of lifts. The more often you have to lift the load, the more the force summates on the back (and the body in general) and once again the greater the risk.

Object Size or Shape. Lifting a really big box (hopefully an exciting present) feels much heavier than a dumbbell of equal weight.

Constant vs Dynamic Load. If the load keep changing weight (a squirming child) it is a more difficult lift than a static load (a sleeping child).

 

If you have any further question or would like to work through lifting mechanics, please contact the team at Institute of Sports and Spines for more information.

Hyperlordosis - Are you Over Arching?

on Friday, 26 May 2017. Posted in Newsletters, General Health, Ergonomics, Chiropractic

Hyperlordosis - Are you Over Arching?

Hyperlordosis - Are you Over Arching?

Hyper Lordosis – Are you Over Arching? 

 

Tight Psoas 

Anterior pelvic tilt is the postural position where your butt sticks out more, accentuating the arch on your lower back. So say if you are overarching the lower back doing a back squat or a plank, the odds are high you are over tilting your pelvis forward.

 

Overtime, this issue can contribute to a disc bulge/slipped disc due to the overloading and pressure on the back part of the disc during overextension of the spine and let's not forget the probability of a hip impingement as well from the jamming of the pelvic and femur together in hip flexion and internal rotation.

Facet Joints in Motion

We tend to see this problem a lot more often now as we do spend long hours sitting at a desk or in the car which over activates the hip flexors and lengthens the hip extensors; causing a forward pull of the pelvis.

 

Some of the signs and symptoms of anterior pelvic tilt are:

1.back pain/stiffness especially standing for long periods and/or lying flat on back

2.tight hamstrings

3.gut (protruding belly)

4.gluteal muscles (butt muscles)

5.curve in the lower spine

 

In order to correct this dysfunction, we have to solve the muscle imbalances around the pelvic area. APT is more a stability issue than a mobility one. That being said though, the mobility side of things still need to be addressed.

 

 

Important tight muscles to be stretched to tackle the mobility issues are:

Hip Flexors - https://youtu.be/ut4mGaPvbZk

Hip Flexor 1 Hip Flexor 2

 

Erector Spinae - https://youtu.be/P_4yDo-hiHw  

Erector Spinae 

 

Rectus Femoris (The Quad muscles) - https://youtu.be/ei9Gh6RogDg

Rectus Femoris 

Do these stretches 10-15 times, hold 10-15 seconds post workout and throughout the day. 

 

As mentioned above, the root of APT is from the lack of muscle stability to hold your spine in a neutral position. Without these muscle controls, the body then tries to lock the joints together for stability instead (therefore the overextension of the lower back in squats when further loaded with a barbell/weights).  

 

When addressing stability, start off by reactivating these few muscles: 

Transverse Abdominis (Core stability) – https://youtu.be/T6CaTUBTtUA

Transverse Abdominis 1 Transverse Abdominis 2

Glutes - https://youtu.be/depTc0ME7wk

Glutes 1 Glutes 2

 

Pelvic mobility - https://youtu.be/CU7w8zjrzIc

Pelvic Mobility 1 Pelvic Mobility 2

 

Start with 10-15 reps throughout the day increasing to 30 reps as you progress and have better control.

 

I highly recommend these reactivation exercises to be done in the mornings to ease off any tension built during sleep the night before and before bedtime to de-load the body after a long stressful day at work.

 

You may not feel much progress on the first day, but persist for a week or more; a difference in pain intensity and stiffness will definitely be noticeable!

 

By Iris Tan

B.App.Sc (Chiropractic) M.Clin.Chiropractic. 

Memb: CA, Gonstead (Australia)

Iris picture new contrast