Fryette’s Laws

Fryette’s Laws?
Fryette's Laws, Lovett, motion coupling, osteopath, osteopathy, physiological motion, spinal kinematics, spinal motion In many institutions, and particularly in the USA, there seems to be tacit acceptance of the idea that the physiological motion of the spine can be reliably predicted and explained by reference to 'Fryette's Laws'. Given that nearly 100 years have elapsed since the ideas were originally formulated, why are they still being used?












Harrison M Fryette(1876-1960) was an early ‘pioneer’ osteopath who researched spinal motion over a number of years, with a seminal paper on the principles of spinal motion delivered to the American Osteopathic Association in 1918. However, it was some time before his ideas gained ground, until they were eventually revisited and relabelled as ‘laws’ as late as 1956 by T Edward Hall in the yearbook of the Osteopathic Institute of Applied Technique. The original principles were: Principle I: When the spine is in neutral, sidebending to one side will be accompanied by horizontal rotation to the opposite side. Principle II: When the spine is flexed or extended (non-neutral), sidebending to one side will be accompanied by rotation to the same side. a third principle was added in the 1940s by CR Nelson Principle III: When motion is introduced in one plane it will modify (reduce) motion in the other two planes.
Since the 1950s the osteopathic and chiropractic community have been enthusiastic in their adoption of these principles to the extent that they even appear in the Glossary of Osteopathic Terminology published by the American Osteopathic association (AOA) and questions based on these principles appear in state board examinations, set as current biomechanical theory and not as historical footnotes. Interestingly, the ‘laws’ as now published specifically exclude the cervical spine, as a result of a conflict between the original principles and the weight of current research findings.


On what basis were these ideas formulated?
Fryette drew heavily on earlier work conducted by Lovett in 19051. The research methodology consisted of cadaveric study and in vivo research via the application of gummed paper stickers to the spinous processes of a small number of student volunteers. The results were obtained by observing relative motion of these gummed paper stickers, and inferring as a consequence, the nature of the underlying spinal motion which had occurred.

Over the last century kinematic research has progressed from direct observation, cadaveric study, radiological analysis, cineradiology, CT, MRI, Steinman pins, implanted Gallium balls, to computer modelling. The more we are able to visualise and research living spinal motion, the more complex and unpredictable is the precise combination of individual joint rotation and translation for each region and segment. Rather than definitive ‘laws’ it appears that there are substantial individual and regional variations with, as yet, no accurate model for predicting all of the motion behaviour. With all this uncertainty why do some of us still persist in promoting a model for physiological motion based on work conducted over 100 years ago? The work of Fryette must be applauded for it’s longevity and insight, and celebrated as part of our osteopathic heritage and history, but the ‘laws’ can no longer be viewed as such, nor do they serve as a viable explanation of physiological motion behaviour.
Time to move on, and as Fryette2 himself emphasised: ‘No intelligent scientific spinal technic can be developed that is not based on an accurate understanding of the physiological movements of the spine’
1. Lovett RW (1905) The mechanism of the normal spine and its relation to scoliosis. Boston Med Surg J 13:349–358 ↩
2. Fryette H H; Principles of Osteopathic Technic, The Academy of Applied Osteopathy 1954 p.16
Fryette's Laws is a set of three laws pertaining to skeletal anatomy named after Harrison Fryette, D.O. It is defined as a set of guiding principles used by practitioners of osteopathic medicine to discriminate between dysfunctions in the axial skeleton. The first two laws solely apply to the lumbar and thoracic spinal regions, but the third applies to the entire vertebral column.[1] The first two laws were developed by Dr. Fryette in 1918, and the third was developed by C.R. Nelson, D.O in 1948.[2]
[edit] The three principles
1. Principle I: When the spine is in neutral, sidebending to one side will be accompanied by horizontal rotation to the opposite side. In type I somatic dysfunction this law can be seen when more than one vertebrae are out of alignment and cannot be returned to neutral by flexion or extension. The involved group of vertebrae demonstrates a coupled relationship between side bending and rotation. When the spine is neutral, side bending forces are applied to a group of typical vertebrae and the entire group will rotate toward the opposite side: the side of produced convexity [3] Extreme type I dysfunction is similar to scoliosis.
2. Principle II: When the spine is flexed or extended (non-neutral), sidebending to one side will be accompanied by rotation to the same side. In type II somatic dysfunction of the spine, this law can be seen when only one vertebrae is out of place and becomes much worse on flexion or extension. There will be rotation and sidebending in the same direction when this dysfunction is present.[4]
3. Principle III: When motion is introduced in one plane it will modify (reduce) motion in the other two planes.[5] Type III sums up the other two laws by stating dysfunction in one plane will negatively affect all other planes of motion.
[edit] References
1. ^ Fryette's Laws
2. ^ Robert G Savarese, John D Capobianco, James J Cox, JR. OMT Review, 3rd ed.
3. ^ Nelson, K and Glonek, T. Somatic Dysfunction in Osteopathic Family Medicine. Philadelphia: Lippincott Williams & Wilkins. p. 455.
4. ^ Greenman PE. Principles of Manual Medicine. Baltimore: Williams and Wilkins; 1989:58-60
5. ^ Greenman PE. Principles of Manual Medicine. Baltimore: Williams and Wilkins; 1989:58-60

Plantar Fasciitis: Evidence-Based Review of Diagnosis and Therapy

December 1, 2005 Table of Contents

Plantar Fasciitis: Evidence-Based Review of Diagnosis and Therapy

CHARLES COLE, M.D., CRAIG SETO, M.D., and JOHN GAZEWOOD, M.D., M.S.P.H., University of Virginia School of Medicine, Charlottesville, Virginia

Am Fam Physician. 2005 Dec 1;72(11):2237-2242.

  Patient Information Handout

Plantar fasciitis causes heel pain in active as well as sedentary adults of all ages. The condition is more likely to occur in persons who are obese or in those who are on their feet most of the day. A diagnosis of plantar fasciitis is based on the patient’s history and physical findings. The accuracy of radiologic studies in diagnosing plantar heel pain is unknown. Most interventions used to manage plantar fasciitis have not been studied adequately; however, shoe inserts, stretching exercises, steroid injection, and custom-made night splints may be beneficial. Extracorporeal shock wave therapy may effectively treat runners with chronic heel pain but is ineffective in other patients. Limited evidence suggests that casting or surgery may be beneficial when conservative measures fail.

Plantar fasciitis commonly causes inferior heel pain and occurs in up to 10 percent of the U.S. population. Plantar fasciitis accounts for more than 600,000 outpatient visits annually in the United States.1 The condition affects active and sedentary adults of all ages. Plantar fasciitis is more likely to occur in persons who are obese, who spend most of the day on their feet, or who have limited ankle flexion.2 Experts believe that the pain is caused by acute or chronic injury to the origin of the plantar fascia from cumulative overload stress.

SORT: KEY RECOMMENDATIONS FOR PRACTICE

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Clinical recommendation	Evidence rating	References
Off-the-shelf insoles, but not magnetic insoles, should be considered to manage plantar fasciitis symptoms.	B	13,14
Custom-made insoles should be considered to decrease plantar heel pain, but they are not more effective than fabricated insoles.	B	14,16
Stretching of the plantar fascia is more effective than calf stretching and should be recommended for all patients with pain.	B	17
Corticosteroid iontophoresis should be considered for short-term relief of plantar heel pain if initial therapy fails.	B	16
Custom-made night splints should be considered to relieve plantar heel pain.	B	16
Extracorporeal shock wave therapy is not effective and should only be used to treat runners with chronic heel pain.	B	16,19–22
A walking cast should be considered for patients with plantar fasciitis who have not responded to conservative measures.	C	23
Open or endoscopic surgery should be considered for patients with plantar fasciitis in whom all conservative measures have failed.	B	24–28

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A = consistent, good quality patient-oriented evidence; B = inconsistent or limited quality patient-oriented evidence; C = consensus, disease-oriented evidence, usual practice, expert opinion, or case series. For more information about the SORT evidence rating system, see page 2160 or http://www.aafp.org/afpsort.xml.

Diagnosis

Diagnosis of plantar fasciitis is based on the patient’s history and on results of the physical examination. Patients typically present with inferior heel pain on weight bearing, and the pain often persists for months or even years. Pain associated with plantar fasciitis may be throbbing, searing, or piercing, especially with the first few steps in the morning or after periods of inactivity. The discomfort often improves after further ambulation but worsens with continued activity, often limiting daily activities. Walking barefoot, on toes, or up stairs may exacerbate the pain.3  The patient usually has tenderness around the medial calcaneal tuberosity at the plantar aponeurosis. A number of other conditions cause heel pain; most of these can be distinguished from plantar fasciitis by a history and physical examination (Table 14–8).

TABLE 1
Differential Diagnosis of Heel Pain

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Condition		Characteristics
Neurologic
Abductor digiti quinti nerve entrapment		Burning in heel pad
Lumbar spine disorders		Pain radiating down the leg to the heel, weakness, abnormal reflexes
Problems with the medial calcaneal branch of the posterior tibial nerve		Medial and plantar heel pain
Neuropathies		Common in patients who abuse alcohol and in patients with diabetes
		Diffuse foot pain, night pain
Tarsal tunnel syndrome		Pain, burning sensation, and tingling on the sole of the foot
Soft tissue
Achilles tendonitis		Pain is retrocalcaneal
Fat pad atrophy		Pain in area of atrophic heel pad
Heel contusion		History of trauma
Plantar fascia rupture		Intense tearing sensation on bottom of foot
Posterior tibial tendonitis		Pain on the inside of the foot and ankle
Retrocalcaneal bursitis		Pain is retrocalcaneal
Skeletal
Calcaneal epiphysitis (Sever’s disease)		Heel pain in adolescents
Calcaneal stress fracture		Calcaneal swelling, warmth, and tenderness
Infections		Osteomyelitis
		Systemic symptoms (e.g., fever, night pain)
Inflammatory arthropathies		More likely with bilateral plantar fasciitis
		Multiple joints affected
Subtalar arthritis		Heel pain is supracalcaneal
Miscellaneous
Metabolic disorders
	Osteomalacia	Diffuse skeletal pain, muscle weakness
	Paget’s disease	Bowed tibias, kyphosis, headaches
	Sickle cell disease	Acute episodes of pain involving long bones, pelvis, sternum, ribs
		Dactylitis in young children
Tumors (rare)		Deep bone pain, night pain, constitutional symptoms
Vascular insufficiency		Pain in muscle groups that is reproducible with exertion, abnormal vascular examination

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Information from references 4 through 8

Diagnostic imaging is not helpful in diagnosing plantar fasciitis, but it should be considered if another diagnosis is strongly suspected. According to several small case-control studies9,10 that compared patients with and without plantar fasciitis, thicker heel aponeurosis, identified by ultrasonography, is associated with plantar fasciitis. Radiography may show calcifications in the soft tissues around the heel or osteophytes on the anterior calcaneus (i.e., heel spurs). Fifty percent of patients with plantar fasciitis and up to 19 percent of persons without plantar fasciitis have heel spurs.11 The presence or absence of heel spurs is not helpful in diagnosing plantar fasciitis. Bone scans can show increased uptake at the calcaneus, and magnetic resonance imaging can show thickening of the plantar fascia.11 However, the accuracy of these tests remains inconclusive.

Prognosis

Case series and the control arms of therapy trials12–14 provide the best evidence regarding the prognosis of patients with plantar fasciitis.12–14 Most patients with plantar fasciitis eventually improve.4 In one long-term follow-up study,12 investigators found that 80 percent of patients treated conservatively for plantar fasciitis had complete resolution of pain after four years.

Therapy

GENERAL MEASURES

Treatment protocols in most studies include the use of ice and nonsteroidal anti-inflammatory drugs (NSAIDs). However, no studies have specifically examined the effectiveness of these treatments alone.

TAPING

No studies have adequately evaluated the effectiveness of taping or strapping for managing plantar fasciitis.

SHOE INSERTS

Many types of shoe inserts have been used to manage plantar fasciitis. One randomized controlled trial13 (RCT) showed that magnet-embedded insoles were no more effective than placebo insoles in alleviating pain. Another study14 that compared custom orthotics and prefabricated shoe inserts (e.g., silicone heel pad, felt pad, rubber heel cup) combined with stretching found that the use of prefabricated insoles plus stretching was significantly more effective than custom orthotics plus stretching. Only five patients would need to be treated with prefabricated insoles to benefit one.

NIGHT SPLINTS

Posterior-tension night splints maintain ankle dorsiflexion and toe extension, creating a constant mild stretch of the plantar fascia that allows it to heal at a functional length. Physicians can make custom splints in the office15 or purchase prefabricated splints. One Cochrane review16 found limited evidence to support the use of night splints to treat patients with pain lasting more than six months. Patients treated with custom-made night splints improved, but patients treated with prefabricated night splints did not.16

STRETCHING

Stretching protocols often focus on the calf muscles and Achilles tendon or on the plantar fascia itself (Figure 1).17 In a prospective RCT17 that compared these two approaches, researchers found that patients who stretched the plantar fascia showed a greater decrease in “pain at its worst” and a decrease in pain with first steps in the morning. Both groups, however, experienced an overall decrease in pain. The benefits of stretching both the plantar fascia and the Achilles tendon are unknown.

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Figure 1.

Plantar fascia–specific stretch. Patient crosses affected foot over contralateral leg, grasps the base of toes, and pulls the toes back towards the shin until a stretch in the arch is felt. The stretch is held for 10 seconds and repeated. Three sets of 10 repetitions are performed daily.

Information from reference 17.

CORTICOSTEROID INJECTIONS

Limited evidence supports the use of corticosteroid injections to manage plantar fasciitis. Results of a Cochrane review16 showed that corticosteroid injections improved plantar fasciitis symptoms at one month but not at six months when compared with control groups. The same review showed that steroid iontophoresis also improved short-term outcomes. However, physicians should be cautious about administering this treatment, because corticosteroid injection is associated with plantar fascia rupture, which may cause long-term discomfort.18

EXTRACORPOREAL SHOCK WAVE THERAPY

Recent systematic reviews16,19 have evaluated RCTs that studied the effectiveness of extra-corporeal shock wave therapy (ESWT) in the management of heel pain. In general, the reviewers found that the quality of the studies was poor and that no conclusive evidence supported the effectiveness of ESWT in reducing night pain, resting pain, and pressure pain in the short term (i.e., within six and 12 weeks).
Since the release of these systematic reviews, three groups have published RCTs20–22 that studied ESWT. Two well-designed RCTs20,22 compared ESWT with a placebo procedure in patients with chronic plantar fasciitis. Neither study found a significant difference between the treatment and control groups three months after treatment. One RCT21 included 45 runners who had chronic heel pain for more than 12 months. According to the study, three weekly treatments of ESWT significantly reduced morning pain in the treatment group at six and 12 months when compared with the control group.

CASTING

In one case series,23 investigators studied 32 patients with chronic heel pain who had not responded to multiple treatments. For six months, the patients wore well-padded fiberglass walking casts with the ankle in neutral to slight dorsiflexion and the toe plate in extension. At long-term follow-up, 25 percent of patients had complete resolution of pain, and an additional 61 percent had some improvement.23 However, case series and other uncontrolled studies typically overestimate the benefits of treatment.

SURGERY

No RCTs have evaluated the effectiveness of surgery in the management of plantar fasciitis. Five retrospective case series,24–28 which included 278 patients who had experienced pain for an average of 14 months before surgery, showed that 75 to 95 percent of patients had long-term improvement as measured by various criteria. Up to 27 percent of patients still had significant pain, up to 20 percent had some activity restriction, and up to 12 percent had moderate pain that impaired function. The recovery time ranged from four to eight months. No studies have directly compared open procedures with endoscopic procedures.

Recommendations

No evidence strongly supports the effectiveness of any treatment for plantar fasciitis, and most patients improve without specific therapy or by using conservative measures.4,12,16 Shoe inserts and stretching exercises, particularly those that focus on the plantar fascia, may be beneficial and should be the first step in treatment. Although no data support the use of NSAIDs or ice, their effectiveness in managing other musculoskeletal conditions makes them reasonable choices for adjunctive therapy.14,17
For patients who do not improve after initial treatment, corticosteroid injection or dexamethasone (Decadron) iontophoresis may provide short-term benefit. However, these therapies do not improve long-term outcomes16 and may cause plantar fascia rupture.18 Custom-made tension night splints that place the metatarsophalangeal joints in extension may be beneficial for patients who do not respond to initial therapy, but the benefits of prefabricated night splints have not been proved.16 ESWT is not beneficial except in runners who have had chronic heel pain for more than one year.16,19–22 If conservative measures fail, the physician may choose to refer the patient to a subspecialist for further therapy and possibly surgery. The optimal timing of referral is uncertain, particularly given the self-limited nature of the condition in most patients.24–28 Guidelines3 from the American College of Foot and Ankle Surgeons recommend considering surgery if the pain persists after three months of treatment. The effectiveness of surgery compared with conservative measures remains unproved, but many patients who have not benefited from conservative treatment report long-term improvement following surgery. However, a substantial number of patients will have a prolonged recovery period and will experience continued limiting pain.24–28 Limited data suggest that casting may be a beneficial alternative to surgery.23
Data Sources: For this article, a medical librarian searched PreMEDLINE, the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effectiveness, and the American College of Physicians Journal Club using the mapped heading “heel pain” and the text words “plantar fasciitis.” The medical librarian also searched MEDLINE (1996 to 2003) and Pre-MEDLINE using the mesh heading “plantar, fasciitis” and the text words and mapped heading “plantar heel pain.” She searched MEDLINE using OVID from 1998 on using a search strategy identical to that used by Clinical Evidence Concise.29 She reviewed randomized trials, diagnostic studies, and surgical case series published after the initial Cochrane review in 1998. She also hand-searched bibliographies of selected articles.

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The Authors

CHARLES COLE, M.D., is assistant professor of family medicine at the University of Virginia School of Medicine, Charlottesville, and associate medical director of Stoney Creek Family Practice, Nellysford, Va. Dr. Cole earned his medical degree from the University of Maryland School of Medicine, Baltimore, and was chief resident in family medicine at the University of Virginia School of Medicine.

CRAIG SETO, M.D., is assistant professor of family medicine at the University of Virginia School of Medicine. Dr. Seto earned his medical degree from Eastern Virginia Medical School, Norfolk, and completed a family medicine residency at Eisenhower Army Medical Center, Fort Gordon, Ga. He completed fellowships in faculty development at the University of North Carolina at Chapel Hill School of Medicine, and in sports medicine at the Hughston Sports Medicine Clinic, Columbus, Ga.

JOHN GAZEWOOD, M.D., M.S.P.H., is associate professor of family medicine and is the family medicine predoctoral program director at the University of Virginia School of Medicine. He earned his medical degree from Vanderbilt University School of Medicine, Nashville, and completed a family medicine residency at the University of Missouri–Columbia School of Medicine. After five years in private practice, he earned a Master of Science in Public Health degree and completed faculty development and geriatric fellowships at the University of Missouri–Columbia School of Medicine.

Address correspondence to John Gazewood, M.D., M.S.P.H., P.O. Box 800729, Department of Family Medicine, University of Virginia Health System, Charlottesville, VA 22908 (e-mail: jdg3k@virginia.edu). Reprints are not available from the authors.

Author disclosure: Nothing to disclose.

The authors thank Karen Knight, MLS, for her assistance with the literature search.

Members of various family medicine departments develop articles for “Evidence-Based Medicine.” This is one in a series from the Department of Family Medicine at the University of Virginia, Charlottesville. Coordinator of the series is David Slawson, M.D.
 

REFERENCES

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2. Riddle  DL, Pulisic  M, Pidcoe  P, Johnson  RE.  Risk factors for plantar fasciitis: a matched case-control study [published correction appears in J Bone Joint Surg Am 2003;85–A:1338].  J Bone Joint Surg Am.  2003;85–A:872–7.

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14. Pfeffer  G, Bacchetti  P, Deland  J, Lewis  A, Anderson  R, Davis  W, et al.  Comparison of custom and prefabricated orthoses in the initial treatment of proximal plantar fasciitis.  Foot Ankle Int.  1999;20:214–21.

15. Petrizzi  MJ, Petrizzi  MG, Roos  RJ.  Making a tension night splint for plantar fasciitis.  Phys Sportsmed.  1998;26:113–4.

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18. Acevedo  JI, Beskin  JL.  Complications of plantar fascia rupture associated with corticosteroid injection.  Foot Ankle Int.  1998;19:91–7.

19. Boddeker  R, Schafer  H, Haake  M.  Extracorporeal shockwave therapy (ESWT) in the treatment of plantar fasciitis—a biometrical review.  Clin Rheumatol.  2001;20:324–30.

20. Speed  CA, Nichols  D, Wies  J, Humphreys  H, Richards  C, Burnet  S, et al.  Extracorporeal shock wave therapy for plantar fasciitis. A double blind randomised controlled trial.  J Orthop Res.  2003;21:937–40.

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22. Haake  M, Buch  M, Schoellner  C, Goebel  F, Vogel  M, Mueller  I, et al.  Extracorporeal shock wave therapy for plantar fasciitis: randomised controlled multicentre trial.  BMJ.  2003;327:75.

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24. Brown  JN, Roberts  S, Taylor  M, Paterson  RS.  Plantar fascia release through a transverse plantar incision.  Foot Ankle Int.  1999;20:364–7.

25. Davies  MS, Weiss  GA, Saxby  TS.  Plantar fasciitis: how successful is surgical intervention?.  Foot Ankle Int.  1999;20:803–7.

26. Fishco  WD, Goecker  RM, Schwartz  RI.  The instep plantar fasciotomy for chronic plantar fasciitis. A retrospective review.  J Am Podiatr Med Assoc.  2000;90:66–9.

27. Boyle  RA, Slater  GL.  Endoscopic plantar fascia release: a case series.  Foot Ankle Int.  2003;24:176–9.

28. Vohra  PK, Giorgini  RJ, Sobel  E, Japour  CJ, Villalba  MA, Rostkowski  T.  Long-term follow-up of heel spur surgery. A 10-year retrospective study.  J Am Podiatr Med Assoc.  1999;89:81–8.

29. BMJ Clinical Evidence Concise. Searching Medline for systematic reviews. Accessed online March 10, 2004, at: http://www.clinicalevidence.com/ceweb.about/mlsr.jsp.

Courtesy : aafp.org