Clinically Predicting Gravity

Today’s post is a guest post by Terry Pratt, PT, MS, COMT, FAAOMPT; the newest addition to the ranks of NAIOMT Faculty Instructor.

This will be the first in a series of posts addressing current research in physical therapy and applying appropriate concepts from a clinical and scientific perspective.

Researchers recently determined through observation, pattern recognition and logic that the Virtruian man, deemed as a perfect representation of the homosapian male, may have had a left inguinal hernia. Recent physical therapy research has strayed from simply observing and predicting motion of patients in a gravitational environment, and in doing so are missing similar answers to clinical problems which are right in front of us. Long gone should be the days when spinal motion is predicted and researched without consideration of gravity, patient expectations and use of general techniques which require little skill. Spinal motion is best predicted in the context of gravity, patient expectations and highly skilled techniques.

A perfect example are the clinical prediction rules (CPRs). Although CPRs have existed in medicine for many years and the number of research articles mentioning CPRs have doubled in the last decade, very few have been validated and fewer still are in common use by practitioners 1. The most successful CPRs in clinical practice to date are for DVT and the Ottawa Ankle Rules for ankle fractures. Stanton et al. concluded that at this juncture the evidence that CPRs predict the effects of treatment for musculoskeletal conditions is very limited2.

After billions of dollars spent investigating the assessment and treatment of low back pain, researchers have concluded that “no treatment strategy, surgical or conservative has been shown to be consistently effective in reducing the often persistent symptoms, functional limitations, and disability associated with this condition.”3 In the same article the authors suggest that there is a lack of specificity in the patho-anatomical diagnosis of low back pain. A second hypothesis is that research frequently does not account for the influence the laws of physics (including Newton’s Laws of Gravity), have on the tissues of the human body4.

This is actually encouraging, because by returning to observing our patients and performing a selective tissue tensioning test with a thorough biomechanical assessment, the answer to this frustrating problem is right in front of our eyes. Clinical prediction rules can be helpful, but, as Dr. Paris stated in his 2011 Distinguished Lecturers Award, the evidence “is pretty thin and in some cases it can be downright misleading.” In addition, he states that CPRs (published literature) are just one leg of a three legged stool for evidence based practice, with the other two being patient’s wishes and culture and the individual therapist’s expertise.5

A recent bright spot in the literature is an article in Spine validating the Multifidus Lift Test6. In this test the patient is in the quadruped position and asked to extend their hip and straighten their knee while the therapist palpates the multifidus muscle at the L4/L5 or L5/S1 levels. Thirty two subjects were in the study which compared the accuracy of palpation of the mutifidus contraction to real time ultrasound. This test validated a therapist’s ability to palpate accurately at specific spinal levels the activation of the multifidus. While ultrasound is an excellent diagnostic tool and is useful to increase a patient’s mind body awareness, the machine is quite expensive and is not practical in an everyday clinical setting. Also, the Multifidus Lift Test is performed in quadruped, which is not a functional and habitually used posture.

An alternative suggestion for assessing multifidus activation (with the understanding that the multifidus contracts in conjunction with the rest of the deep core stabilizers) is having the patient forward flex their shoulder in standing. Firstly, it is well established that the multifidus muscle contracts prior to the prime mover with functional tasks7. Secondly, standing is a functional position and the patient can easily incorporate this task into a self-management program. Activation of the core system occurs PRIOR to initiation of shoulder flexion (right arm flexion would be the deep fibers of the left multifidus). The deep core stabilizers contract prior to the motion because the body is preparing for an anterior displacement of weight and the center of gravity.

In assessment, the therapists can be behind the patient and palpate the multifidus on both sides at the L4/5 levels. While palpating, ask the patient to flex their shoulder in the plane of the scapula (30 degrees lateral to forward flexion). The therapist should feel the contralateral deep fibers of the multifidus contract prior to the shoulder motion, as happens with contralateral limb motion in patients without a history of low back pain8. Difficulty in sensing multifidus contraction may be due to the patients standing in a hyperlordoic posture or the patient may have to have to add some resistance (1-2# weight). Also, while palpating the therapist may notice an asymmetry in the multifidus tone, which is the first clue that the patient may have trouble transferring load and stabilizing on that side.

This assessment technique can be provided as a home exercise program by having the patent contract their deep core stabilizers (Kegals are a good cue) after they activate them during shoulder flexion. While lowering the arm the patient will try to maintain a light contraction (20%) of their deep core stabilizers (anterior and posterior pelvic floor). The core stabilizers do not contract like an on and off switch, but more like a dimmer switch. This timing is of utmost importance rather than strength. The patient can practice activating the core several times an hour so that the input to the nervous system reflects normal functional activity.

Although the position of the Multifidus Lift Test is not optimal, the validation of our skills of specificity and palpation is a step in the right direction. CPRs by nature have to start general and work towards specific for validation purposes. As practitioners we do not have time to wait for research to achieve the specificity we need for optimal outcomes. By continually reviewing and modifying current research to better simulate common human movement patterns in a gravity based environment, we can apply validated techniques and at the same time provide feedback to the researchers so the profession and patient rehabilitation can move forward.

References

1. Toll DB, Janssen KJM, Vergouwe Y, Moons KGM. Validation, updating and impact of clinical prediction rules: a review. J Clin Epidemiol. 2008;61(11):1085–94. doi:10.1016/j.jclinepi.2008.04.008.

2. Stanton TR, Hancock MJ, Maher CG, Koes BW. Critical appraisal of clinical prediction rules that aim to optimize treatment selection for musculoskeletal conditions. Phys Ther. 2010;90(6):843–54. doi:10.2522/ptj.20090233.

3. Childs JD, Flynn TW. Clinical Decision Making for Low Back Pain: A Step in the Right Direction. J Orthop Sport Phys Ther. 2014;44(1):1–2. doi:10.2519/jospt.2014.0101.

4. Pettman E. NAIOMT. In: Level III Advanced Lower Quadrant. Berrien Springs, Michigan; 2001.

5. Paris S. Past Present and Future of Joint Manipulation. Univ St Augustine. 2011;(February):1–28.

6. Hebert J, Koppenhaver S, Teyhen D, Walker B, Fritz J. The evaluation of lumbar multifidus muscle function via palpation : reliability and validity of a new clinical test . Spine (Phila Pa 1976). 2013;9430(13):4–5. doi:10.1016/j.spinee.2013.08.056.

7. MacDonald D a, Moseley GL, Hodges PW. The lumbar multifidus: does the evidence support clinical beliefs? Man Ther. 2006;11(4):254–63. doi:10.1016/j.math.2006.02.004.

8. Urquhart DM, Hodges PW, Allen TJ, Story IH. Abdominal muscle recruitment during a range of voluntary exercises. Man Ther. 2005;10(2):144–53. doi:10.1016/j.math.2004.08.011.