Interexaminer Reliability and Validity for Diagnosis of Temporomandibular Disorders of Visual Leg Measurements Used in Dental Kinesiology

Aims: To determine the reliability and the validity of visual leg measurements used in dental kinesiology, which suggests that a masticatory dysfunction, such as occurs in temporomandibular disorders (TMD), can influence the length and the internal rota-tion of lower limbs. Methods: The leg-length inequality test and the internal foot-rotation test were performed independently by 3 different examiners on 41 subjects who were also screened for TMD. Data were analyzed by means of kappa statistics and by calculation of sensitivity and specificity values. Results: Chance-corrected reliability was generally poor for both the leg-length inequality test (0.33 ≤ k ≤ 0.39) and the internal foot-rotation test (0.15 ≤ k ≤ 0.27). Sensitivity and specificity values of the tests to differentiate TMD and healthy subjects were below acceptable thresholds; they ranged from 0.41 to 0.57. Conclusion: Visual evaluations of leg-length inequality and internal foot rotation were unreliable and are not valid for TMD diagnoses. The results of chiropractic visual leg measurement procedures in dentistry should be interpreted with caution, particularly when clinical decisions may lead to nonreversible dental treatment.

chiropractic; diagnostic tests; leg-length inequality; reliability; temporomandibular disorders

1. Hellsing E, McWilliam J, Reigo T, Spangfort E. The relationship between craniofacial morphology, head posture and spinal curvature in 8, 11 and 15 years old children. Eur J Orthod 1987;9:254–264.

2. Huggare JA, Raustia AM. Head posture and craniovertebral and craniofacial morphology in patients with craniomandibular dysfunction. J Craniomandib Pract 1992;10:173–178.

3. Kritsineli M, Shim YS. Malocclusion, body posture, and temporomandibular disorder in children with primary and mixed dentition. J Clin Pediatr Dent 1992;16:86–93.

4. Darlow LA, Pesco J, Greenberg MS. The relationship of posture to myofascial pain dysfunction syndrome. J Am Dent Assoc 1987;114:73–75.

5. Hellsing E, Reigo T, Mc William J, Spangfort E. Cervical and lumbar lordosis and thoracic kyphosis in 8, 11 and 15- year-old children. Eur J Orthod 1987;9:129–138.

6. Huggare J, Pirttiniemi P, Serlo W. Head posture and dentofacial morphology in subjects treated for scoliosis. Proc Finn Dent Soc 1991;1:151–158.

7. Valentino B, Melito F. Functional relationship between the muscles of mastication and the muscles of the leg. An electromyographic study. Surg Radiol Anat 1991;13:33–37.

8. Valentino B, Fabozo A, Melito F. The functional relationship between the occlusal plane and the plantar arches: An EMG study. Surg Radiol Anat 1991;13:171–174.

9. Gole DR. A clinical observation: A relationship of occlusal contacts to distal musculature. Cranio 1993;11:55–62.

10. Chinappi AS, Getzoff H. The dental-chiropractic cotreatment of structural disorders of the jaw and temporo-mandibular joint dysfunction. J Manipulative Physiol Ther 1995;18:476–481.

11. Eversaul G. Dental Kinesiology. Las Vegas: Author, 1977.

12. Michelotti A, Manzo P, Farella M, Martina R. Occlusion and posture: Is there evidence of correlation? [in Italian]. Minerva Stomatol 1999; 48:525–534.

13. Walther DS. Applied Kinesiology. Vol 1: Basic procedure and muscle testing. Pueblo CO: Systems DC, 1981.

14. Jensen CR, Schultz GW, Bangerter BL. Applied Kinesiology, ed 3. Vol 2: Head, neck and jaw pain and dysfunction. The stomatognathic system. New York: McGraw-Hill, 1983.

15. Dworkin SF, LeResche L. Research Diagnostic Criteria for Temporomandibular Disorders: Review, criteria, examinations and specifications, critique. J Craniomandib Disord 1992;6:301–355.

16. Fuhr AW, Osterbauer PJ. Interexaminer reliability of relative leg length evaluations in the prone extended position. Chiropractic Technique 1989;1:13–18.

17. Cohen J. A coefficient of agreement for nominal scales. Educ Physiol Meas 1960;20:37–46.

18. Landis J, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159–174.

19. Fleiss JL, Cohen J, Everitt BS. Large sample standard errors of kappa and weighted kappa. Psychol Bull 1969;72:323–377.

20. Fleiss JL. The measurement of interrater agreement. In: Statistical Methods for Rates and Proportions, ed 2. New York: John Wiley & Sons, 1981:212–236.

21. Specht DL, De Boer KF. Anatomical leg length inequality, scoliosis and lordotic curve in unselected clinic patients. J Manipulative Physiol Ther 1991;14:368–375.

22. Knutson GA. Incidence of foot rotation, pelvic crest unleveling, and supine leg length alignment asymmetry and their relationship to self-reported back pain. J Manipulative Physiol Ther 2002;25:110E [erratum 2002;25:425].

23. Hestbœk L, Leboeuf-Yde C. Are chiropractic tests for the lumbo-pelvic spine reliable and valid? A systematic critical literature review. J Manipulative Physiol Ther 2000;23:258–275.

24. Hinson R, Brown SH. Supine leg length differential esti-mation: An inter- and intra-examiner reliability study. Chiropractic Res J 1998;5:17–22.

25. Rhudy TR, Burk JM. Inter-examiner reliability of functional leg-length assessment. Am J Chiropractic Med 1990;2:63–66.

26. Grundy PF, Roberts CJ. Does unequal leg length cause back pain? A case-control study. Lancet 1984;4;2: 256–258.

27. Mannello DM. Leg length inequality. J Manipulative Physiol Ther 1992;15:576–590.

28. Friberg O, Nurminen M, Korhonen K, Soininen E, Manttari T. Accuracy and precision of clinical estimation of leg length inequality and lumbar scoliosis: Comparison of clinical and radiological measurements. Int Disabil Stud 1988:10:49–53.

29. Rhodes DW, Mansfield ER, Bishop PA, Smith JF. The validity of the prone leg check as an estimate of standing leg length inequality measured by x-ray. J Manipulative Physiol Ther 1995:18:343–346.

30. Boline PD, Keating JC, Brist J, Denver G. Interexaminer reliability of palpatory evaluations of the lumbar spine. Am J Chiropractic Med 1988;1:5-11.

31. American Academy of Orofacial Pain. Okeson JP (ed). Orofacial Pain. Guidelines for Assessment, Diagnosis, and Management. Chicago: Quintessence, 1996.

32. Dworkin SF, Huggins KH, LeResche L, et al. Epidemiology of signs and symptoms in temporomandibular disorders: Clinical signs in cases and controls. J Am Dent Assoc 1990;120:273–281.