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. 2015 Spring;4(1):27–30.

Incidence of Vertical Phoria on Postural Control During Binocular Vision: What Perspective for Prevention to Nonspecific Chronic Pain Management?

Eric Matheron 1, Zoï Kapoula 1
PMCID: PMC4389295  PMID: 25861672

Abstract

Vertical heterophoria (VH) is the latent vertical misalignment of the eyes when the retinal images are dissociated, vertical orthophoria (VO) when there is no misalignment. Studies on postural control, during binocular vision in upright stance, reported that healthy subjects with small VH vs. VO are less stable, but the experimental cancellation of VH with an appropriate prism improves postural stability. The same behavior was recorded in nonspecific chronic back pain subjects, all with VH. It was hypothesized that, without refraction problems, VH indicates a perturbation of the somaesthetic cues required in the sensorimotor loops involved in postural control and the capacity of the CNS to optimally integrate these cues, suggesting prevention possibilities. Sensorimotor conflict can induce pain and modify sensory perception in some healthy subjects; some nonspecific pain or chronic pain could result from such prolonged conflict in which VH could be a sign, with new theoretical and clinical implications.

Key Words: Vision, Vertical Heterophoria, Postural Control, Back Pain, Nonspecific Pain, Sensorimotor Conflict, Prevention


Today, it is not possible to ignore the role of vision and eye movements involved in postural control and the tonic activity in Human (eg (1-8)). Vision and gaze signals influence the vestibuloocular, the vestibulospinal and the reticulospinal systems (see (9)). And we cannot ignore the importance of body somatosensory signals on the mobilization of the eye and the visual perception of our surrounding space (eg (10-15)). In the daily life, balance, posture and movement control is complex. For instance, postural control in quiet upright stance, the Human reference posture and also the basis for body stability during movements and gait (see (16,17)), requires the central integration of visual, vestibular and somaesthetic inputs. The central nervous system performs appropriate coordinate transformations of these inputs and permanently generates adapted muscular response (e.g.(4,18)).

Various experimental investigations were run to contribute for better understanding about the mechanisms and complexes interaction between vision, oculomotricity, and postural control, notably studies about vertical phoria. When the retinal images are dissociated, vertical heterophoria (VH) is the latent vertical misalignment of the eyes reduced via binocular vision mechanisms, and vertical orthophoria (VO) when there is no misalignment (19,20). Physiological VH was reported in normal subjects, inferior to one diopter, on average 0.28 diopter, corresponding to 0.16±0.01° (21). Nevertheless, studies reported that VH experimentally induced in healthy young adult subjects by the insertion of a 1 degree-vertical prism influences postural stability, notably a decrease of postural stability during the quiet upright stance (22). Other results clearly showed that healthy subjects with VH vs. VO (VH less than 1 diopter) are less stable, but the cancellation of VH with an appropriate prism improves postural stability (23). In line with this, in nonspecific chronic back pain subjects with an additional comorbidity such as peripheral arthralgia, muscle pain, dizziness, headache, or eyestrain known (e.g. (24,25)), representing up to 85% of back pain (26), all with VH, the same behavior was recorded (27). Interestingly, these subjects needed more energy to stabilize their posture compared in healthy subjects, but the energetic cost decreased when VH was canceled (27). Beside eye refraction problems (19,28), it was hypothesized that VH, even when small in size, indicates a perturbation of the somaesthetic cues required in the sensorimotor loops involved in postural control and could perhaps indicate the capacity of the central nervous system to integrate these cues optimally, suggesting prevention possibilities (see (23)).

It is known that sensorimotor conflict (at least between vision and proprioceptive cues) can induce pain and modify sensory perception in some healthy subjects (29); we hypothesized that non-specific chronic back pain could result from such prolonged conflict in which VH could be a sign, with new theoretical and clinical implications (see (27)). This speculation, beyond to be in line with the experimental model introduced by McCabe et al. (29), agrees with the suggestions of Harris (30): i) discordance between awareness of motor intention, muscle and joint proprioception, and vision could lead to pain perception, and ii) when pain exists – without medical pathologic support as organic lesion, rheumatism, neuropathy nor injuries, sprain or fracture –, instead of treating the painful body part with medication, the therapy management should “ be directed at restoring the integrity of cortical information processing”.

Clinical studies suggested the use of VH detection - via the Maddox Rod Test, one of the more robust for the small vertical deviation (31,32) - as a landmark in the management of nonspecific chronic pain, non-contact injuries (e.g. tendinitis, muscle pain). For instance, VH can be linked to conflict from the stomatognathic system, the pelvis, piercings (body art, i.e., with jewelry) or refractive error; cancel the conflict most of the time restored VO immediately, diminished pain (33-35), improved mobility of spinal and peripheral joints, and normalized behaviour in the balance tests after initial alternation (33,34,36), but remain to be precisely evaluated – e.g. with objective measurements of heterophoria (e.g. with the use of an eye tracker) and movement (e.g. 3D motion capture). The exact causal relationship has to be identified. Nevertheless, as previously discussed on theoretical aspects (35), these various afferences (i.e. visual, vestibular and somaesthetic) project to the cerebellum, the reticular formation, and the vestibular nucleus (see (37)) which are located at the base of the spinal motor neurons and oculomotor efferents (see (38)). Yet, based on these experimental studies and clinical reports, on the impact of afferences required for motor control in various tasks and muscle efficiency performance, the possibility of degradation of postural control in upright stance and possible pain linked to sensorimotor conflict, perspective in optimization of muscular efficiency and at least in nonspecific chronic pain management should be of interest.

DISCLOSURE

The authors have no financial or proprietary interest in materials presented herein.

References

  • 1.Paulus WM, Straube A, Brandt T. Visual stabilization of posture Physiological stimulus characteristics and clinical aspects. Brain. 1984;107:1143–1163. doi: 10.1093/brain/107.4.1143. PMID: 6509312. [DOI] [PubMed] [Google Scholar]
  • 2.Brandt T, Paulus W, Straube A. Vision and posture. In: Bles W, editor. Disorders of posture and gait. Univ. of Munich, Germany: Amsterdam, New-York, Oxford: Elseiver; 1986. pp. 160–161. [Google Scholar]
  • 3.Roll JP, Vedel JP, Roll R. Eye, head and skeletal muscle spindle feedback in the elaboration of body references. Prog Brain Res. 1989;80:113–123. doi: 10.1016/s0079-6123(08)62204-9. PMID: 2634269. [DOI] [PubMed] [Google Scholar]
  • 4.lvanenko YP, Grasso R, Lacquaniti F. Effect of gaze on postural responses to neck proprioceptive and vestibular stimulation in humans. J Physiol. 1999;519:301–314. doi: 10.1111/j.1469-7793.1999.0301o.x. PMID: 10432359. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.lvanenko YP, Grasso R, Lacquaniti F. Neck muscle vibration makes walking humans accelerate in the direction of gaze. J Physiol. 2000;525:803–814. doi: 10.1111/j.1469-7793.2000.t01-1-00803.x. PMID: 10856131. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Strupp M, Glasauer S, Jahn K, Schneider E, Krafczyk S, Brandt T. Eye movements and balance. Ann N Y Acad Sci. 2003;1004:352–358. doi: 10.1196/annals.1303.033. PMID: 14662475. [DOI] [PubMed] [Google Scholar]
  • 7.Glasauer S, Schneider E, Jahn K, Strupp M, Brandt T. How the eyes move the body. Neurology. 2005;65:1291–1293. doi: 10.1212/01.wnl.0000175132.01370.fc. PMID: 16051645. [DOI] [PubMed] [Google Scholar]
  • 8.Lê TT, Kapoula Z. Role of ocular convergence in the Romberg quotient. Gait Posture. 2008;27:493–500. doi: 10.1016/j.gaitpost.2007.06.003. PMID: 17669653. [DOI] [PubMed] [Google Scholar]
  • 9.Berthoz A. The role of gaze in compensation of vestibular disfunction : the gaze substitution hypothesis. Progress in Brain Research. 1988;76:411–420. doi: 10.1016/s0079-6123(08)64528-8. PMID: 3064159. [DOI] [PubMed] [Google Scholar]
  • 10.Bronstein AM, Hood JD. The cervico-ocular reflex in normal subjects and patients with absent vestibular function. Brain Res. 1986;373:399–408. doi: 10.1016/0006-8993(86)90355-0. [DOI] [PubMed] [Google Scholar]
  • 11.Roll JP, Roll R. [Extraocular proprioception as an element of postural reference and spatial coding of retinal information] Agressologie. 1987;28:905–912. PMID: 3445896. [PubMed] [Google Scholar]
  • 12.Roll JP, Roll R. From eye to foot: a proprioceptive chain involded in postural control. In: Amblard B, Berthoz A, Clarac F, editors. Posture and Gait: Development, Adaptation, and Modulation Proceedings of the 9th International Symposium on Postural and Gait Research, Marseille. Amsterdam: Elseiver: Marseille, France; 1988. pp. 155–164. [Google Scholar]
  • 13.Karlberg M, Magnusson M, Johansson R. Effects of restrained cervical mobility on voluntary eye movements and postural control. Acta Otolaryngol. 1991;111(4):664–670. doi: 10.3109/00016489109138397. PMID: 1950528. [DOI] [PubMed] [Google Scholar]
  • 14.Corneil BD, Olivier E, Munoz DP. Visual responses on neck musclesreveal selective gating that prevents express saccades. Neuron. 2004;42:831–841. doi: 10.1016/s0896-6273(04)00267-3. PMID: 15182721. [DOI] [PubMed] [Google Scholar]
  • 15.Blohm G, Khan AZ, Ren L, Schreiber KM, Crawford JD. Depth estimation from retinal disparity requires eye and head orientation signals. J Vis. 2008;8(16):3,1–23. doi: 10.1167/8.16.3. PMID: 19146270. [DOI] [PubMed] [Google Scholar]
  • 16.Massion J. Movement, posture and equilibrium: interaction and coordination. Prog Neurobiol. 1992;38(1):35–56. doi: 10.1016/0301-0082(92)90034-c. PMID: 1736324. [DOI] [PubMed] [Google Scholar]
  • 17.Gurfinkel VS, Ivanenko YuP, Levik YuS, Babakova IA. Kinesthetic reference for human orthograde posture. Neuroscience. 1995;68(1):229–243. doi: 10.1016/0306-4522(95)00136-7. PMID: 7477928. [DOI] [PubMed] [Google Scholar]
  • 18.Nashner LM. Adapting reflexes controlling the human posture. Exp Brain Res. 1976;26:59–72. doi: 10.1007/BF00235249. [DOI] [PubMed] [Google Scholar]
  • 19.Amos FJ, Rutstein R. Vertical deviation. In: Amos FJ, editor. Diagnosis and management in vision care. Amsterdam, New-York, Oxford: Butterworths; 1987. pp. 515–583. [Google Scholar]
  • 20.von Noorden GK. Binocular vision and ocular motility: theory and management of strabismus. 5e Edition. St.Louis: Mosby; 1996. [Google Scholar]
  • 21.van Rijn LJ, Ten Tusscher MPM, de Jong I, Hendrikse F. Asymmetrical vertical phorias indicating dissociated vertical deviation in subjects with normal binocular vision. Vision Res. 1998;38:2973–8. doi: 10.1016/s0042-6989(98)00079-0. PMID: 9797992. [DOI] [PubMed] [Google Scholar]
  • 22.Matheron E, Lê TT, Yang Q, Kapoula Z. Effects of a two-diopter vertical prism on posture. Neuroscience Letters. 2007;423(3):236–240. doi: 10.1016/j.neulet.2007.07.016. PMID: 17709195. [DOI] [PubMed] [Google Scholar]
  • 23.Matheron E, Kapoula Z. Vertical phoria and postural control in upright stance in healthy young subjects. Clinical Neurophysiology. 2008;119:2314–2320. doi: 10.1016/j.clinph.2008.06.016. PMID: 18760665. [DOI] [PubMed] [Google Scholar]
  • 24.von Korff M, Crane P, Lane M, Miglioretti DL, Simon G, Saunders K, Stang P, Brandenburg N, Kessler R. Chronic spinal pain and physical-mental comorbidity in the United States: results from the national comorbidity survey replication. Pain. 2003;113(3):331–339. doi: 10.1016/j.pain.2004.11.010. PMID: 15661441. [DOI] [PubMed] [Google Scholar]
  • 25.Hagen EM, Svensen E, Eriksen HR, Ihlebaek CM, Ursin H. Comorbid subjective health complaints in low back pain. Spine. 2006;31(13):1491–5. doi: 10.1097/01.brs.0000219947.71168.08. PMID: 16741460. [DOI] [PubMed] [Google Scholar]
  • 26.Deyo RA. Measuring the functional status of patients with low back pain. Arch Phys Med Rehabil. 1988;69:1044–1053. PMID:2975164. [PubMed] [Google Scholar]
  • 27.Matheron E, Kapoula Z. Vertical heterophoria and postural control in nonspecific chronic low back pain. PLoS One. 2011;6(3) doi: 10.1371/journal.pone.0018110. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Matheron E, Weber B. Implication de l'entrée visuelle dans les asymétries toniques posturales : approche clinique. In: Perennou D, et al., editors. Efficience et déficiences du contrôle postural. Marseille: Solal; 2006. pp. 261–270. [Google Scholar]
  • 29.McCabe CS, Haigh RC, Halligan PW, Blake DR. Simulating sensory–motor incongruence in healthy volunteers: implications for a cortical model of pain. Rheumatology. 2005;44(4):509–516. doi: 10.1093/rheumatology/keh529. PMID:15644392. [DOI] [PubMed] [Google Scholar]
  • 30.Harris AJ. Cortical origin of pathological pain. The Lancet. 1999;354:1464–1466. doi: 10.1016/S0140-6736(99)05003-5. PMID: 10543687. [DOI] [PubMed] [Google Scholar]
  • 31.Daum KM. Heterophoria and Heterotropia. In: Eskridge JB, Amos JF, Bartlett JD, editors. Clinical procedures in optometry. Philadelphia: J.B. Lippincott Compagny; 1991. pp. 72–90. [Google Scholar]
  • 32.Wong AM, Tweed D, Sharpe JA. Vertical misalignment in unilateral sixth nerve palsy. Ophthalmology. 2002;109:1315–25. doi: 10.1016/s0161-6420(02)01067-9. PMID:1209365. [DOI] [PubMed] [Google Scholar]
  • 33.Matheron E, Quercia P, Weber B, Gagey PM. Vertical heterophoria and postural deficiency syndrome. Gait Posture. 2005;21(S132):20–23. [Google Scholar]
  • 34.Matheron E, Barlaud P, d'Athis P. Evaluation des hétérophories verticales en vision de loin sur des sujets arthralgiques et/ou rachialgiques dits chroniques, et incidence de leur normalisation par kinésithérapie proprioceptive spécifique. In: Lacour M, et al., editors. Bipédie, contrôle postural et représentation corticale. Marseille: Solal; 2005. pp. 213–220. [Google Scholar]
  • 35.Matheron E, Kapoula Z. Face piercing (body art): choosing pleasure vs possible pain and posture instability. Front Physio. 2011;2 doi: 10.3389/fphys.2011.00064. doi: 10.3389/fphys.2011.00064. PMID: 21960975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 36.Matheron E. [Vertical heterophoria and myotonic normalization] Kinésithér Scient. 2000;34:23–28. [Google Scholar]
  • 37.Capra NF, Dessem D. Central connections of trigeminal primary afferent neurons: topographical and functional considerations. Crit Rev Oral Biol Med. 1992;4:1–52. doi: 10.1177/10454411920040010101. PMID: 1457683. [DOI] [PubMed] [Google Scholar]
  • 38.Büttner-Ennever JA. Neuroanatomy of the oculomotor system. Prog Brain Res. 2006;151:1–574. doi: 10.1016/S0079-6123(05)51019-7. PMID:16221583. [DOI] [PubMed] [Google Scholar]

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