Low Back Pain Related to Hyperlordosis

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Definition

“Low back pain (LBP) has been related with anthropometric, postural, muscular, and mobility characteristics” [1] Lumbar lordosis is a key feature in maintaining sagittal balance.[2]. It is one of the most important parts of the spinal pillar that has a special importance due to the unique position and having a direct contact the pelvis. [3]. Sagittal balance or “neutral upright sagittal spinal alignment” is a postural goal of surgical, ergonomic and physiotherapeutic intervention. [2]

Clinically Relevant Anatomy

If a straight lumbar spine articulated with the sacrum, it would consequently be inclined forwards. To restore an upward orientation and to compensate for the inclination of the sacrum, the intact lumbar spine must assume a curve. This curve is known as the lumbar lordosis.[4]

A normal lumbar lordosis is characterized by an average lumbosacral angle of 39° - 53°.[5], the results depend on how the lumbosacral angle is measured and there is an enormous difference in lumbosacral angle over patients. However, when the curvature of the lumbar spine is very pronounced, it refers to hyperlordosis or swayback, this means that the lumbosacral angle and the lumbar index (the chord of the lumbar lordosis) increase.[5]

In addition to the bones, ligaments, muscles and vertebral discs have also a key role in lordosis curvature. Without muscle action, the performance of pelvic girdle would not have sufficient stability. Central stabilize of the vertebral column is supported by special muscles such as multifidus, transversus abdominis and internal muscles in the trunk. They provide stability of vertebrae in a focal form and provide also segmental stabilization by controlling motion in the neutral zone. The neutral zone can be regained to within physiological limits by effective muscle control.

Women have less vertebral wedging in the lower thoracic and upper lumbar vertebrae, they have relatively greater interspinous space and larger inter facet within lumbar hyperlordosis in. These anatomical features could explain the altered vertebral morphology predisposing to pregnancy.

Women also have a less kyphotic posture of the upper and the lower thoracic area than males. Furthermore, the trunk’s center of mass is maintained in an approximate sagittal alignment with the hip thus reducing biomechanical load and facilitating spinal extension. There is an advantage of this deeper lordosis- less kyphotic female spine because there is a larger superior-inferior space for the human fetus. The downside of this morphological feature is the resultant size reduction of the intervertebral foramen which in turn may contribute to low back pain commonly experienced in pregnancy.[6]

Epidemiology

Low back pain is a common health problem in our society. Most people will experience low back pain at some point in their life. The lifetime prevalence of low back pain is reported to be as high as 84% and best estimates suggest that the prevalence of chronic low back pain is about 23%, with 11-12% of the population being disabled by it. All age groups are affected by low back pain.[7]

Etiology

There are a lot of etiological factors that can be linked to low back pain[1]:

  • Obesity
  • Poor abdominal muscle strength and imbalance in trunk muscle strength[8] [9]
  • Reduced spinal mobility
  • Tight hamstrings
  • Differences in leg length between the right and left leg
  • Decreased back extensor muscle endurance[10]
  • Increased lumbar lordosis

Low back pain related to hyperlordosis

An increase in lordotic angle proportionally increases the shearing strain or stress in the anterior direction and shifts the center of gravity anteriorly. This increased angle and stress are thought by some to be associated with poor posture and back pain. From a biomechanical point of view, the accentuated lumbar lordosis is associated with an increased prevalence of low back pain. [3]However several studies have concluded that low back pain is not directly related to lumbar hyperlordosis. There are factors that contribute to a higher amount of lumbar lordosis. These etiological factors, like the weakness of the trunk, short back muscles, weak thigh and hamstrings, etc. in turn can cause low back pain.

It is important to mention that not solely the lumbar hyperlordosis is the causing factor for low back pain.It is thus not reasonable to conclude that there is a relationship between LBP and the size of the lumbar lordosis.[10] On the other hand, it is likely that trunk muscle weakness can influence the shape of the lumbar lordosis and might be a cause of LBP.[3]

The multifidus, transversus abdominis and internal muscles in the trunk act late in patients suffered from hyperlordosis. [3] There is a correlation between the weakness of the trunk muscles and an increased lordotic angle, which can be a cause of low back pain[1]. Weakness in any of the muscles of the lumbar-pelvic belt can follow pelvic rotations and diversions of back-arc by impairing muscular balance in this area and thus a person can be prone to musculoskeletal disorders.[3]

There are various factors affecting lumbar lordosis. Some studies show that the range of lumbar lordosis is affected by age, sex, movement in the center of mass such as pregnancy and obesity.[3] Possible causes of hyperlordosis:

  • congenital spine deformities
  • anterior tilt of the hip
  • short back muscles
  • too weak thigh and hamstrings due to a muscular imbalance (lower crossed syndrome): the postural muscles shorten in response to stress and they, in turn, inhibit their antagonists

Lumbar hyperlordosis is known as ‘swayback’ or ‘hollow back’. 
There is an increasing recognition of the importance (functional and clinical) of lumbar lordosis. It is a key feature in maintaining sagittal balance. It has been claimed that flattening or loss of normal lumbar lordosis is an important clinical sign of back problems.
People with low back pain have reduced lumbar ROM and proprioception. Their stabilizing muscles act more slowly compared to people without LBP. Normally the stabilizing muscles are activated before the movement is initiated, but in people with low back pain, this contraction is delayed.[11]

Differential Diagnosis

It’s essential to make the difference between specific and non-specific low back pain because they need a specific treatment.[12]

Specific low back pain

Clinical Presentation

  • Pain in the leg, in the path of the ischiadicus nerve
  • Paresthesia
  • Straight leg raise test is positive
  • Loss of power

This group of patients had a clear underlying pathology, which causes the low back pain:

Non-specific low back pain

When there are no red flags and no clear underlying pathophysiology, we talk about non-specific low back pain.

Red flags

It’s important to recognize red flags in spinal conditions during the anamnesis and during the further examination and treatment because they can indicate an underlying pathology[13]

  • Weight loss, without an indication.
  • age: < 20 years old and > 55 years old
  • Comorbidities or previous history of cancer, HIV, infections,...
  • Widespread neurological symptoms
  • Night pain
  • Bladder dysfunction
  • Trauma

Diagnostic Procedures

Medical imaging

Radiographs can be used to measure the lumbar angle.[5]

There are several methods to measure the lumbar angle:

  • Between the inferior endplate of T12 and the superior endplate of S1: This one had the best intraobserver reproducibility.
  • Between the superior endplate of L1 and the superior endplate of S1
  • Between the superior endplate of L1 and the inferior endplate of L5 [1]: This one had the best overall agreement between several observers
  • Between the inferior endplate of T12 and the inferior endplate of L5

There are several kinds of medical images, which can each be used to diagnose different things. For example X-rays to measure the lumbar curvature, MRI-scans to investigate soft tissue abnormalities, CT-scans to visualize the intervertebral discs

Lordosis X-ray
Decreased Lordosis X-ray


Outcome Measures


There are identified six main domains relevant to the assessment of patients with low back pain: pain symptoms, function, well being, work disability, social disability and satisfaction with care. These suggestions were made by a group of low back pain experts and were accepted by the spine-research community.

Several instruments have been developed and validated for the evaluation of these dimensions. These techniques are especially useful for routine clinical practice or in large-scale quality assessment. [7] pain symptoms and function:

     • Oswestry Disability Index is the most effective for persistent severe disability. Oswestry Disability Index [14]
     • Roland-Morris Disability Questionnaire is better for mild to moderate disability. Roland‐Morris Disability Questionnaire [14]

Prevention

Ascertaining the normal values of lordosis in children is essential for early detection and treatment of postural abnormalities. [2]
The strongest risk factor for future low back pain is a previous low back pain. So primary intervention does not seem to be a realistic aim. There are not many strong and alterable factors found, which can cause low back pain for the first time.


Only exercise intervention seems to be effective. [7] and when you combine it with education, it also appears to have a positive effect. Other interventions, including education alone, back belts, and shoe insoles, do not appear to prevent LBP.[15]

Examination

The evaluation depends on age and presence of red flags. The examination techniques used to evaluate LBP depend on the population and the activity that reproduces the pain should be evaluated. [16]

Inspection


An inspection can provide valuable information on muscle weakness. Therefore, it is recommended not to skip the inspection. We look at the depth of lumbar lordosis and any sagittal deviations.

Spine curves 

Radiographic examination is the gold standard to evaluate spine curves, but ionizing radiations limit routine use. [17]Non-invasive methods, such as skin-surface goniometer (IncliMed) should be used instead. It is a pocket compass needle goniometer. [17]

  • The lumbar angle and sacral angle can be measured with a goniometer. The sacral angle is the angle between the horizontal line parallel to the bottom end and the superior endplate of the sacrum. The lumbar angle can be measured between the Inferior endplate of L5 and the superior endplate of L1: this is called the method of Cobb.[1] However, the reliability of the goniometer is still questioned. [18]
  • The flexible ruler may be of clinical value in the assessment of exercise or postural adjustments attempting to increase or decrease a patient's lumbar lordosis. In such an assessment, the flexible ruler would only have to indicate an increased or decreased angle. [18] The patient remains in the normal standing position while measuring the lordotic curve.
  1. The flexible curve should be pressed against the spinous processes of the lumbosacral spine and the points that intersected the adhesive markers have to be recorded.
  2. The points that intersected L1 and S2 could be marked and a line drawing between them.

These two measurements are used to calculate an index of lordosis (Θ), using the following formula: Θ = 4[Arctan2H/L]
(Θ=The index of lordosis, L = the length of the curve and H=the height of the curve.) [3]

Manual muscle testing

It is commonly accepted that trunk musculature and intra-abdominal pressure produced by muscular activity stabilize spinal structures. Chiropractors and physicians also accepted that abdominal and back musculatures affect pelvic inclination and lumbar lordosis. There is a relation between the lordotic angle and the flexor-extensor muscle strength. [1]

Manual muscle tests is used to see if there is muscle weaknesses with a score from 0 (no muscle activity) to 5 (normal muscle activity) during the following  movements:


• Trunk extension
• Trunk flexion
• Elevation of the pelvis

Medical management

Since lumbar hyperlordosis is just a contributing factor in producing low back pain it is needed to look further for other causes. When serious and specific causes of low back pain have been ruled out it is suggested to follow NICE guidelines for early management.

Information, education and patient preferences

Provide people with advice and information to promote self-management of their low back pain.

  • Offer educational advice that:
  1. includes information on the nature of non-specific low back pain
  2. encourages the person to be physically active and continue with normal activities as far as possible.
  • Include an educational component consistent with this guideline as part of other interventions, but do not offer stand-alone formal education programmes.
  • Take into account the person's expectations and preferences when considering recommended treatments, but do not use their expectations and preferences to predict their response to treatments.

Pharmacology

First medication option should be regular paracetamol. Offer non-steroidal anti-inflammatory drugs (NSAIDs) and/or weak opioids (codeine and dihydrocodeine) when paracetamol or NSAIDs provided insufficient pain relief. [19] Give due consideration to the risk of side effects from NSAIDs, especially in older people and other people at increased risk of experiencing side effects.

Surgery

Surgical intervention can be considered when the lumbar lordosis curve is severe, the conservative treatment alone failed and if there are signs of neurologic involvement. Signs of neurologic involvement are the loss of sensory perception of touch, loss of reflexes and loss of muscle fiber recruitment. Surgical correction can be done anteriorly and posteriorly.

Physical therapy management

First, it is needed to be certain that there are no indications for surgery. It’s beneficial to start with physical therapy in combination with medication.
Physical therapy management should be aimed towards improving the patient’s ADL and reducing low back pain. As discussed before, the factors contributing to the LBP can be very diverse, therefore is important to know what the causing factors are to set therapeutic goals that are realistic for the patient.

Manual therapy 

Several guidelines also recommend manual therapy, including spinal manipulation in a frequency/duration of a maximum of nine sessions over twelve weeks. [19]

Exercise therapy

Exercise therapy, including supervised exercises, appears to be slightly effective at decreasing pain and improving function in adults with chronic low-back pain, particularly in healthcare populations. Patients with an acute outburst of low back pain who received exercise therapy in addition to the medical management had fewer recurrences over a long time. [20] Decreasing the extension forces on the lumbar spine must be the purpose of the exercises. This can result in a decreased lumbar lordosis.  Exercises should be done on a regular basis to reach maximum effect.

Williams Training Protocol [3]

This is an exercise protocol for men under 50 years and women under 40 years which had a lumbar hyperlordosis, whose radiography showed a contraction of the lumbar segment interarticular space. The purpose of these exercises was to reduce pain and to ensure the stability of the lower trunk by toning the abdominal muscles, buttocks, and hamstrings altogether with the passive extent of hip flexors and sacrospinalis muscles. Each group performed special training for 8 weeks:

• 3 sessions per week: about 1 hour.

• Duration of each exercise: 8 to 10 seconds in each set.

• Protocols were started with 1 set of 10 repetitions at starting baseline and by improving performance and patients’ compatibility with training, all eventually finished with 3 sets of 20 repetitions at the end of protocols.

1-Pelvic Tilt:

The patient lies on his back with knees bent, feet flat on floor.

Cue: Flatten the small of your back against the floor, without pushing down with the legs, hold for 5 to 10 seconds.

2- Single Knee to chest:

The patient lies on his back with knees bent and feet flat on the floor.

Cue: Slowly pull your right knee toward your shoulder and hold 5 to 10 seconds. Lower the knee and repeat with the other knee.

3- Double knee to chest:

The patient begins as in the previous exercise.

Cue: Pulling right knee to chest, pull left knee to chest and hold both knees for 5 to 10 seconds. Slowly lower one leg at a time.

4- Partial sit-up:

The patient has to do the pelvic tilt (exercise 1) and while holding this position

Cue: Slowly curl your head and shoulders off the floor. Hold briefly. Return slowly to the starting position.

5- Hamstring stretch:

The patient starts in long sitting with toes directed toward the ceiling and knees fully extended.

Cue: Slowly lower the trunk forward over the legs, keeping knees extended, arms outstretched over the legs, and eyes focus ahead.

6-Hip Flexor stretch:

The patient places one foot in front of the other with the left (front) knee flexed and the right (back) knee held rigidly straight.

Cue: Flex forward through the trunk until the left knee contacts the axillary fold (armpit region). Repeat with right leg forward and left leg back.

7- Squat:

The patient stands with both feet parallel, about shoulder’s width apart. Attempting to maintain the trunk as perpendicular as possible to the floor, eyes focused ahead, and feet flat on the floor.

Cue: Slowly lower the body by flexing the knees.

Strengthening exercises[21]
  • Isometric and isotonic exercises: May be beneficial for strengthening of the main muscle groups of the trunk, which stabilizes the spine and it can also decrease the pain.

The patient should gradually build up these exercises until he can hold it for 10 x 10sec. [22]

Through core strength training, patients with chronic low back pain can strengthen their deep trunk muscles.

There is an enormous range of exercises on the ground to increase core stability. [22]

  • Motor control exercises: Seem to have beneficial effects on pain and disability. [23]

The patient needs to learn to activate the transversus abdominis muscle and at the same time to breath normally during the exercise. Palpation can give him/her feedback.

The next step would be a co-contraction with the multifidus muscle and the pelvic floor muscles.

When the patient has a good performance of this exercise, the physical therapist could combine the exercise with movements of the arms or legs.

After that, the patient should integrate the contraction of the transversus abdominis muscle in the ADL. [24]

Stretching exercises [21]

With a crossed leg syndrome type of problem, it’s beneficial to stretch the tightened muscles. For improving the mobility, the patient could perform stretching of the hamstrings, hip flexors, and lumbar paraspinal muscles over 15 seconds. This will improve the active and the passive ROM in the lower extremity.

  • Hold-relax stretching of the iliopsoas: It can reduce back pain, excessive lumbar lordosis angle, lengthen the iliopsoas and increase transversus abdominis activation capacity. 

The target hip is moved toward the floor until the patient feels a mild stretch sensation. Then the patient must perform a submaximal voluntary isometric contraction of the M. Iliopsoas for 10 seconds and then completely relax for 10 seconds. The participant’s leg is now slowly moved to a new range until a mild stretching sensation is felt and described by the patient. This position is then held for 20 seconds. This is repeated 5 times, followed by a 1 min rest, for 15 minutes. [25]

  • Stretching technique for improving the ROM of the M.Iliopsoas and the M. Rectus femoris:

The patient lies in Thomas position, the not stretched leg is maximally flexed to stabilize the pelvis and flatten the lumbar spine. The other leg is in a normal flexed position because of the tightness of the M. Iliopsoas. It’s this leg that needs to be pushed against the table. If you want to stretch the M. rectus femoris, bend the knee more than 90°, while performing the same stretch.

  • Lifting techniques
  • Endurance training

In order to bring variation in the therapy, you can perform other sports. The most recommended sports are walking swimming and cross-training. You better avoid contact sports like basketball. [19]

Stabilization exercises

The stabilization exercises may be beneficial for reducing pain and disability. [6] Patients following a supervised spinal stabilization exercise program show higher pain reduction compared to patients following another exercise program. During external perturbation, there is a decreased anterior-posterior displacement.[26]

Sling exercise training

Sling exercise training seems to be effective at reducing the pain intensity and disability levels of LBP patients. The patient is suspended in a system of pulleys. He/She has to move the arms or legs, while he/she keeps the spine in a neutral position. Both the deep and superficial muscles need to contract.[24] The patient can also put only his feet in the sling while he can perform some bridging exercises.

The swiss ball

The exercises on the swiss ball demand contraction of the stabilizing muscles, but there is also a contraction of the rectus abdominis muscle [27]

Exercises to fix sway back

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Graded activity program

In subacute low-back pain, there is some evidence that a graded activity program improves absenteeism outcomes, although evidence for other types of exercise is unclear. In acute low-back pain, exercise therapy is as effective as either no treatment or other conservative treatments.

Cognitive/behavioral approaches

Besides exercise therapy, it is important to work in on psychological factors, cognitive/behavioral approaches. This is important for patients with high levels of disability of significant distress. This is recommended for maximum 100 hours spread over 8 weeks. There must also be given advice and information about self-management. Only a short intervention is needed for short-term improvements. [19]

Clinical bottom line

With regard to lumbar hyperlordosis and based on all these studies, it can be concluded that it is not reasonable that there is a relationship between lumbar pain and the size of the lumbar lordosis. However, more research is needed in this area because the evaluation of the lumbar lordosis curve still belongs to one of the routine physical exams.

References

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  25. Malai, Suthichan, Sopa Pichaiyongwongdee, and Prasert Sakulsriprasert. "Immediate Effect of Hold-Relax Stretching of Iliopsoas Muscle on Transversus Abdominis Muscle Activation in Chronic Non-Specific Low Back Pain with Lumbar Hyperlordosis." J Med Assoc Thai 2015; 98 (Suppl. 5): S6-S11. (evidence level: 2B)
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