Assessment of Lumbar Spine Flexibility

Tom Hewetson
MSc. BSc. (Hons) Ost. Med. D.O.

Introduction
Flexibility is generally agreed to be, the ability to move a joint or combination of joints through a range of motion (ROM) for which they were intended. It may be said that flexibility encompasses two components, joint mobility and soft tissue stretch-ability. An individual lacks flexibility if they are unable to reproduce the normal ROM for that joint or combination of joints. One of the roles of the physical therapist working with sports people is the assessment of flexibility. The normal functioning joint has two barriers to motion, (1), the physiological barrier, a point to which an individual may actively move any given joint(s), and, (2), the anatomical barrier, the point to which the joint(s) may be passively moved beyond the physiological barrier (DiGiovanna, 1991). A third barrier of joint flexibility is the pathological barrier caused by trauma or disease. For the purpose of this essay, pathological barriers of lumbar spine motion are not discussed at length.

The need for lumbar spine flexibility is dictated by the sport in which an individual participates, for example, a formula 1 driver would need less flexibility than a gymnast. As well as inter-sport differences there may also be intra-sport variations, for example a rugby prop forward (whose primary role is strength through short ROM) would conceivably need less flexibility than a scrum half (whose primary role is passing the ball which requires the player to have good all round flexibility of the lumbar spine). The questions being asked are: how valid and reliable is subjective lumbar spine flexibility assessment in clinic (what would seem to be normal clinical practice, certainly normal osteopathic practice)? and, is an objective assessment, such as goniometry (a method of measuring the range of motion or position of a joint, either actively or passively) more valid and reliable? For something to be valid it has to be well grounded on principles and or evidence. As a measurement concept this means that it has to measure what it is supposed to, in this case, joint ROM (flexibility). Reliability means that the measurements are consistently repeatable or reproducible. The following are the cases for subjective assessment, followed by objective and finally the discussion and conclusions.

Subjective
Osteopaths are taught to use observation and palpation to ‘look’ for restrictions of motion (Vickers, 1999). It is normal practice in both orthopaedics (Hoppenfeld, 1976; Bates, 1991; Magee, 1992), and Osteopathy (Chun, 1991; Kutchera et al. 1997), to subjectively assess flexibility of the lumbar spine. ‘Normal practice’ does not necessarily mean that it is the best or most effective. These types of assessments are carried out both actively and passively. According to Magee (1992), the archetypal lumbar spine should be able to flex forward 40˚ to 60˚, extension is normally limited to 20˚ to 35˚, lateral flexion, left and right approximately 15˚ to 20˚ and rotation is normally 3˚ to 18˚. The key words here are ‘normally’; this means that there will be individuals that produce more, or less movement through the lumbar spine (presumably abnormal movement), and ‘approximately’, which means that this is a guess at the ROM. Others like Kapandji (1974) and Fitzgerald et al. (1983) are a bit more specific with their reporting of degrees of motion, but still report them to be ‘approximations’. Those that have done research in this area such as, Maher, et al. (1994), Binkley et al. (1997), Maher et al. (1998), and Van der Wurff, et al. (2000), all agree that there was poor demonstration of reliable outcomes of mobility testing in clinical practice, and that physical therapists should be cautious when making clinical decisions based on subjective evaluation of movement. The general consensus was that there was a need for more research. In contrast to these findings, Boline et al. (1993) reported that there was good to excellent inter-examiner concurrence using observation and palpation and that palpation for pain was the only spinal procedure to show consistent reliability.




Objective
Unfortunately there is relatively little research on lumbar spine flexibility testing using goniometry. In order to maintain continuity, examples of goniometric research on elbow, ankle, scapula and lumbar spine are used. Goodwin et al. (1992) did a comparative study on 3 different types of goniometer. The results showed that, not only was there significant difference between goniometers, that there were also significant differences in tester replication. Their advice was that “interchangeable use of goniometers (and presumably the therapists using the goniometer) was inadvisable”. In a single practitioner clinic this is not a problem, but it could become a problem if one works in a multi-practitioner practice, or as part of a (sports) medical team. Youdas et al. (1993) compared goniometry with visual estimates of ankle joint ROM. They reported “considerable inconsistencies” between 2 or more physical therapists making repeated goniometric and visual measurements. Youdas et al. (1994) reported that goniometer-positioning techniques for scapulohumeral rotation were “clinically unacceptable”. The same holds true for these study’s as the first; interchanging therapists to take readings of the same subject is probably not a good idea, this could create a problem if one is a member of a medical team. Boocock et al. (1994) used a flexible electrogoniometer on the lumbar spine. The outcome was, that this was a good measurement for biomechanical investigation, and would be helpful for the sporting (and ergonomic) fields of study.

Discussion
The questions asked were: how valid and reliable is subjective flexibility assessment of the lumbar spine? and, is an objective assessment such as goniometry more valid and reliable? From the evidence it would seem that neither subjective or goniometric lumbar spine flexibility assessments are completely valid or reliable, but each method has its advantages and disadvantages.




Advantages to subjective assessment are:
• No equipment needed
• No expense
• Normal practice (relatively easy to explain to colleagues, everyone uses this system)
• Easy to do
• Can assess tissues quality (palpation)

Disadvantages are:
• Unreliable
• Not conclusive
• Easy to misinterpret
• Guesswork
• Lack of research in subjective assessment

Advantages of goniometric assessments are:
• Objective measurement
• Can be reproduced / repeated (if done by the same practitioner using the same equipment)
• Acceptable for research
• Good for baseline measurement

Disadvantages are:
• Poor inter-tester reliability
• Poor interchange-ability of equipment
• Can be expensive
• Can be difficult to use
• Lack of research on lumbar spine

A possible reason for the contrast in research for the subjective case is, we are only told that they are “physical therapist”, we are not told what kind of physical therapist they are, or, if they carry out this type of assessment on a regular basis in their respective practices. In the case for Boline et al. (1993), we know that the study was carried out on chiropractors; perhaps they had favourable outcomes and good inter-tester reliability because they are more practised at employing these techniques. Maybe one should employ a combination of subjective expertise and objective measurements. Some form of goniometry could be employed for a baseline measurement for athletes as guidance for when they become injured. As to the possibility of an athlete being assessed and treated by a single practitioner, this may be impractical, especially when seeking a second opinion.

It would be reasonable to assume that an athlete would seek advice from a physical therapist, on treatment of pain, and or rehabilitation from an injury, and that they would seek advice on flexibility from a coach or trainer. It is imperative that we not only understand flexibility training and the ramifications of it, we must also understand the strength training for this region as well, in order to comprehensively assess flexibility. Poor techniques can lead to joint and soft tissue damage. The soft tissues have two main properties, elasticity and plasticity. The elastic tissue returns to their normal length post stretch, while plastic tissues remain elongated. This may be one of the reasons for increased flexibility in many sports people, however, flexibility without stability is worthless and both should be encouraged when training.

Here are some questions to ponder for the future. If both methods are not completely valid or reliable why are they still used? What, are the alternatives? and how expensive are they? Is spinal flexibility assessment in clinic an art or a science? Does it matter what technique one employs to assess the flexibility of the lumbar spine as long as the athlete recovers?








References

1. Bates, B. (1991) The musculo skeletal system. In: A guide to physical examination and history taking pp. 459 – 500. J. B. Lippincott Company.

2. Binkley, J., Stratford, P. W., Gill, C., Maber, C. (1995) Interrater reliability of lumbar accessory motion mobility testing. Physical Therapy, 75 (9): 786 – 795.

3. Boline, P. D., Haas, M., Meyer, J. J., Kassak, K., Nelson, C., Keating, J. C. (1993) Interexaminer reliability of eight evaluative dimensions of lumbar segmental abnormality: Part II. J. Manipulative Physiol. Ther., 16 (6): 363 – 374.

4. Boocock, M. G., Jackson, J. A., Burton, A. K., Tillotson, K. M. (1994) Continuous measurement of lumbar posture using flexible electrogoniometers. Ergonomics, 37 (1): 175 – 185.

5. Chun, L. R. (1991) Motion testing. In: An osteopathic approach to diagnosis and treatment (eds. DiGiovanna, E., Schiowitz, S.) pp. 164 – 175. J. B. Lippincott Company.

6. Fitzgerald, G. K., Wynveen, K. J., Rheault, W. et al. (1983) Objective assessment with establishment of normal values for lumbar spinal region range of motion. Physical Therapy, 63 (11): 1776 – 1781.

7. DiGiovanna, E. (1991) Somatic dysfunction. In: An osteopathic approach to diagnosis and treatment (eds. DiGiovanna, E., Schiowitz, S.) pp. 6 - 12. J. B. Lippincott Company.

8. Goodwin, J., Clark, C., Deakes, J., Burdon, D., Lawrence, C. (1992) Clinical methods of goniometry: a comparative study, Disabil. Rehabil., 14 (1): 10 – 15.

9. Hoppenfeld, S. (1976) Physical examination of the lumbar spine. In: Physical examination of the spine and extremities pp. 237 – 263. Appleton & Lange.

10. Kapandji, A. I. (1974) The lumbar vertebral column. In: The physiology of the joints: the trunk and vertebral column pp 72 – 126. Churchill Livingston.

11. Kutchera, W. A., Jones, J. M., Kappler, R. E., Goodridge, J. P. (1997) Musculoskeletal examination for somatic dysfunction. In: Foundations for osteopathic medicine (eds. Ward, R. C. et al.) pp. 489 – 509. Williams and Wilkins.

12. Magee, D. (1992) Lumbar spine. In: Orthopaedic physical examination (ed. Biblis, M.) pp. 247 – 307. Saunders & Co.

13. Maher, C. G., Adams, R., Shields, R. K. (1994) Reliability of pain and stiffness assessment in clinical manual lumbar spine examination. Physical Therapy, 74 (9): 801 – 811.

14. Maher, C. G., Simmonds, M., Adams, R. (1998) Therapist conceptualization and characterization of the clinical concept of spinal stiffness. Physical Therapy, 78 (3): 289 – 300.

15. Van der Wurff, P., Hagmeijer, R. H., Meyne, W. (2000) Clinical tests of the sacroiliac joint. A systemic methodological review: part 1. Manual Therapy, 5 (1): 30 – 36.

16. Vickers, A. (1999) The manipulative therapies: osteopathy and chiropractic. Bmj.com

17. Youdas, J. W., Bogard, C. L., Suman, V. J. (1993) Reliability of goniometric measurements and visual estimates of ankle joint active range of motion obtained in a clinical setting. Archives of Physical Medicine and Rehabilitation, 74 (10): 1113 – 1118.

18. Youdas, J. W., Carey, J. R., Garrett, T. R., Suman, V. J. (1994) Reliability of goniometric measurements of active arm elevation in the scapular plane obtained in a clinical setting. Archives of Physical Medicine and Rehabilitation, 75 (10): 1137 – 1144.