Lifting injury risk
Last week I came across Muscle & Motion via youtube. They have illustrated well how we move when lifting and potential floors.
It goes on to show why we are better off keeping a neutral spine under load.
Lifting injury risk
Mechanics of pelvic girdle stability and self-bracing in SIJ-related pelvic girdle pain: a review, by Bussey, in Physical Therapy Reviews (2015)
Mechanics of pelvic girdle stability and self-bracing in SIJ-related pelvic girdle pain: a review, by Bussey, in Physical Therapy Reviews (2015)
Background
The sacroiliac joints (SIJ) are a pair of synovial joints situated between the sacrum of the spine and ilium on the left and right sides of the pelvis. They are surrounded by a number of strong ligaments that hold them firmly together. The sacrum is comprised of the five lowest vertebrae of the spine, which are all fused together and do not move against one another like the cervical, thoracic, or lumbar vertebrae. The SIJ are capable of only a small range of motion, although exactly how much movement they can perform is currently unclear. The SIJ have been identified as a common cause of low back pain (LBP), which is a very prevalent musculoskeletal complaint affecting a large proportion of society.
Researchers have estimated that as many as 15 – 30% of cases of LBP might be attributable to the SIJ, although given that diagnosis of the precise cause of low back pain is very difficult, such estimates must necessarily be highly uncertain. The underlying reasons for this potential contribution of the SIJ to cases of low back pain are unclear. It has been suggested that the basic biomechanical functions of the SIJ might well be contributory, given that they appear to play a role during both upright standing and in normal gait. Specifically, it is thought that the SIJ function as shock absorbers during gait and that repeated impacts might cause damage to the overlaying cartilage and consequently osteoarthritis, just as at other load-bearing joints in the body. Osteoarthritis is a chronic, progressive, degenerative joint disorder. It is characterised by constellation of damaging structural changes in a joint, including the areas of articular cartilage and subchondral bone, which can be observed on X-ray imaging scans. Such changes are thought to be instrumental in the development of pain and functional impairment. Originally, osteoarthritis was thought to be entirely a disease of the articular cartilage but more recently research has revealed that the condition is a multifactorial disease of the whole joint and has a very complex pathogenesis involving interactions between various joint tissues. In order to understand the potential for osteoarthritis in the SIJ in addition to its possible contribution to low back pain, many studies performed biomechanical analyses on the SIJ either in standing or during gait. Unfortunately, observations of the SIJ position and movement are very difficult to carry out reliably because of the complex anatomy and surrounding tissues, the very small ranges of motion through which the SIJ move, and large degrees of inter-individual variability.
OBJECTIVE:To review the literature regarding mechanical and motor control factors that might affect pelvic girdle stability and consequently influence the development of chronic posterior pelvic girdle pain.
What happened?
Introduction
The reviewer asserts that the pelvis is the link that permits load to be transferred between the axial skeletal of the spine and the primary bones of the lower body. The transmission of force from the lumbar spine to the head of each femur occurs via the bones of the pelvis and the sacrum. Consequently, stability of this lumbopelvic complex under loading is important for effective, pain-free force transmission.
Mechanical factors
The reviewer explains that the mechanical stability of the pelvis and the lumbopelvic complex can be sub- divided into two sets of factors: static stability, arising from the passive support provided by bones, joint structures, and ligaments, which can be termed “form closure” and dynamic stability, arising from tension provided by and through the surrounding muscles and fascia that compress the joints of the pelvis, which can be termed “force closure”. Form closure is primarily therefore a function of anatomy. Force closure is a function of both muscular strength and co-ordination. Specifically, the reviewer notes that muscular forces exerted by the biceps femoris, erector spinae, gluteus maximus and latissimus dorsi have all been found to increase stiffness of the SIJ, which is indicative of increased force closure. Only the gluteus maximus is directly able to act to close the SIJ, however, with fibers crossing from the sacrum to the ischium of the pelvis, while the actions of the other muscles on the SIJ likely occur through their connection to the thoracolumbar fascia or to the posterior ligamentous structures of the SIJ.
Motor control
The precise co-ordination of the individual muscles around the pelvis may alter the stability of the SIJ. The reviewer notes that individuals with pain have been found display altered control mechanisms in lumbopelvic movements. In particular, it has been noted that the normal (stable) anticipatory postural adjustment strategies that are seen in healthy people are replaced by compensatory postural adjustment strategies in individuals with pain, which are only usually observed in healthy individuals in the act of performing high-load tasks.
What did the researchers conclude?
The researcher concluded that load transfer through the pelvis requires both both form closure and force closure and is therefore a function of anatomical features, muscular strength, and co-ordination.
Limitations
This narrative review was limited in that it was not performed systematically and is therefore heavily dependent upon the opinions of the reviewer.
Lower back: Why so many people have issues and how to maintain a healthy back
Lower back: Why so many people have issues and how to maintain a healthy back
Lower back pain is one of the most common health problems in society today, with a large 50-80% of us being affected at some point in our lives (Cassidy et al 2005). Lower back pain is seen in both athletes as well as non athletes (Carl 2006). There is very little knowledge and research of what actually causes lower back pain but here are some factors, which are believed to play a role.
- We live a more sedentary lifestyle these days, more people prefer to sit at computers than keep active and a lot of jobs involve sitting at desks. Less physical activity is believed to be linked to increased risk of lower back pain (Dijken e t al 2008). Long periods of sitting in a ‘C’ shape at our desks loads up our spine with loading of our discs and the compressive forces on facets. When we relax our back our tummy chills in a ‘ hang over the top of the trouser look’ (Key 2007). We need to think about posture as a slumped position causes an increase of 10x fluid loss from our disc nucleus compared to sitting in a relaxed upright position (Key 2007).
- Less spinal control. The hypermobile person (a person with increased laxity in joints) are at increased risk of lower back pain. Movement is good in the spine but too much can cause too much stress such as wear and tear on the spine. Lumbar stabilisation should be used for patients with increased range of motion of the spine to help control the movements of the spine (Cressey 2009). Poor function of spinal stabilisation muscles = overloading of ligaments and lumbo-pelvic function during activities (Liebenson 2004). Muscles, ligaments and thoracolumbar fascia aid in the stabilisation of the pelvis. Decreased spinal stabilisation increases our chances of injury. The more mobile person should focus on the deep intrinsic stabilisers: transverse abdominis, internal oblique abdominis and multifidus. Other areas that should also be strengthened are the glutes, quadtratus lumborum and latissimus dorsi to aid in stabilisation.
- Don’t just think about the area of pain that is causing the problem, decreased ankle range of motion can also cause issues. Patients with less ankle dorsiflexion (pointing toes to the ceiling) are at increased risk of lower back pain, which can be seen in athletes who squat. This is due to their knees not being able to come sufficiently forwards and once maxed out at their hip range of motion they then use their lower back. Ankle mobility should be 100% implemented in a rehab programme to help maintain a healthy back (Cressey 2009).
- Abdominal weakness (Key 2007). Abdominal strength is very important for a healthy spine. Stronger muscles create an increased intra-abdominal pressure, lengthening the spine and increasing tensile strength therefore, increasing stability of each spinal segment. Abdominal co-contraction with back musculature decreases compressive pressure on discs and the pelvis (Key 2007). As already mentioned about our protracted periods of sitting and being slumped over, our abdominals fall asleep and allow our lumbar spinal segments to increase pressure towards our sacrum, increasing disc compression. Your core allows movement and improves the quality of this; decreased core increases the chance of injury and decreases your quality of movement. Your core is also important for preparation for unexpected situations; for example when you loose technique due to being tired, your core will prevent you from injury (Sheppard, 2015). To improve your midline strength, exercises should not be performed stationary e.g. the plank, this decreases joint nutrition, and works your ability to stay still. Every day we are moving, lifting objects, changing direction, our core needs to be switched on at all times to protect our spine and allow us to perform our natural spinal movements.
- MOVEMENT!
Movement is VERY important for a healthy spine. When you injure your back your first reaction is to not move. Instead of bending your back when going to pick something up, you will begin to go into a more squat position to protect your back. You are actually making your back worse, starving your discs in your back from their drink which is released when spinal movement occurs. This will then increase stiffness of your spine which could then lead to spinal instability (Key 2007). When you stop using the natural range of motion of your back you then begin to use the wrong muscles, increasing your chances of weakness in deep spinal muscles and abdominals.
There are many ways to help maintain a healthy spine so here is some ideas for you to have a play around with.
- Bridging: This helps you regain segmental control and allows spinal segments to move individually.
(Key 2007)
- Rocking along the spine
This is a form of mobilisation, helping release muscles, releases locked facets and provides active decompression of the spine. (Key 2007)
- Functional exercises should be used to enable people with lower back pain to feel benefit throughout their day. Exercises such as lunging, squats and pulling and pushing movements should be used to ensure your engaging your core as much as possible (Liebenson 2004).
A lunge for example will show whether someone has good core, if you struggle with the balance of lunge, it is likely you need to work on your midline (Sheppard 2015).
- Postural setting. Posture is not stationary; we need to ensure we are preforming the correct posture throughout movements and throughout the day (Lo 2015). Its not about forcing our shoulders back, then relaxing to take tension off as this can make you weaker and increase your chance of injury if you become too tense. It’s all about glute activation, ab activation and another good way to think about it is feeling like you’re a puppet getting pulled on by your string to make you taller. This has to be done through repetition to enable your brain to learn your new natural posture (Lo 2015). Now perform any exercise such as lifting an object, lunging, squatting with this new relaxed but tight posture and you will feel stronger and more mobile.
Thank you for reading.
Stay positive, listen to your body, keep movement within pain limits and KEEP YOUR BACK HEALTHY!
References:
Cassidy, J.D; Cobe.P; Carroll, L.J; Kristman, V. (2005). Incidence and cause of lower back pain episodes in the general population. Spine. 30 (24), pp.2517-2823.
Carl,L;Staniski,M.D. (2006). Spondylosis and Spondylolisthesis in athletes. Operative techniques in Sports Medicine. 14 (.), pp.141-146
Cressy, E. (2009). Lower back savers. T Nation.
Dijken, C.B; Fjellman-Wilund, A; Hildingson, C. (2008). Lower back pain, life style factors and physical activity: A population-based study. J rehabil Med. 40, pp.864-869.
Key, S (2007). Back sufferers Bible. Australia: Vermilion.
Liebenson, C. (2004). The relationship of sacroiliac joint stabilisation musculature and lumbo-pevlic instability. Journal of bodywork and movement therapies. 8 , pp.43-45.
Lo, A. (2015). Flatt butt/glutes? Start to work it with the ideal posture. Available: http://physiodetective.com/2015/01/26/flat-butt-glutes-start-to-work-it-with-ideal-posture/. Last accessed 15/6/15.
Sheppard, B. (2015). Core Stability. Available: http://physiodetective.com/2015/04/04/core-stability-podcast-with-brad-sheppard-from-create-pt-wealth/. Last accessed 15/6/15
