Chapter 13 - Contraindications And Complications

Most forms of treatment carry some risk of harm to the patient. While chiropractic procedures are considered relatively safe, special caution is warranted with certain conditions. These include, for example, vertebral artery syndrome, disc herniation, and bone weakening processes.

Prevention of complications from treatment is facilitated when good professional judgment is exercised and quality care is provided. Elements common to all primary care practitioners include good history taking, detailed record keeping, appropriate examination, timely re-evaluation procedures throughout the course of case management, good communication with the patient and appropriate response in the event that an unfortunate incident does occur. When complications from a manipulation occurs, it is of critical importance that the intervention or procedure associated with the onset of the complication not be repeated.

The development of acceptable preventive strategies to minimize future risk should be directed by methods of consensus, supported by continuous evaluation of research, protocol experience, risk management, and peer review programmes. The expected goal of establishing guidelines for standards of practice is to assist practitioners to set and abide by standards which improve all aspects of patient care.

The scope of manipulative incidents and reactions may range from aggravation of the presenting complaint to cerebrovascular accidents arising from a dissecting aneurysm. This review of complications of and contraindications to high-velocity thrust procedures outlines various clinical conditions requiring treatment modification. Other manual procedures (e.g., soft tissue and low force technique procedures) are not addressed in this chapter. Guidelines for sound clinical management and prevention are recommended.

Complication: The unexpected aggravation of an existing disorder, or the onset of an unexpected new disorder as a result of treatment.

Classification of complications:

a) Adverse effect - Any detrimental result of an action or treatment.

b) Reaction - A slight or benign adverse effect of short duration usually lasting no more than a few days.

c) Accident or Incident - An unexpected event occurring by chance, unknown causes, carelessness, negligence, or a combination thereof, resulting in serious or permanent impairment, injury, or fatality.

d) Indirect complication - Delay of diagnosis and appropriate treatment as a consequence of using a procedure or treatment that, in retrospect, has proven to be of no benefit for the condition.

Contraindication - absolute: Any circumstance which renders a form of treatment or clinical intervention inappropriate because it places the patient at undue risk.

Contraindication - relative: Any circumstance which may place the patient at undue risk unless treatment approach is modified.

For definitions see the Glossary at the end of this publication.

Effectiveness

Iatrogenesis

Instability

Manipulable lesion (joint dysfunction, functional spinal lesion, subluxation)

Management

Manual Therapy

See also High-Velocity Thrusting; Manipulation; Mobilization, Soft Tissue Procedures; and Stretching.

Motion Segment

Negligence

Risk Management

Safety

Specialist

Conditions selected have come from a review of the scientific and medicolegal literature as well as insurance claim information.

A. Articular Derangement

1. Arthritides
a) Inflammatory arthritis
b) Sub-acute and chronic ankylosing spondylitis
c) Degenerative joint disease
d) Spondylolysis and spondylolisthesis

2. Fractures, dislocations, and ligamentous instability

3. Atlanto-axial instability

4. Articular hypermobility

5. Post-surgical joint

6. Acute joint and soft tissue injuries

7. Scoliosis

B. Bone Weakening and Destructive Disorders

1. Juvenile osteochondroses

2. Osteoporosis and osteomalacia

3. Benign bone tumours, tumour-like and dysplastic bone lesions

4. Malignancy

5. Infection of bone and joint

C. Circulatory and Cardiovascular Disorders

1. Vertebrobasilar insufficiency syndrome

2. Aneurysm

3. Bleeding disorders

D. Neurological Disorders

1. Myelopathy and cauda equina syndrome

Over the past two decades there has been a rapid increase in the literature on manipulation-induced accidents or injuries (Haldeman and Rubinstein 1993, Dvorak 1991, Patijn 1991, Schmitt 1991, Frumkin and Baloh 1990, Terrett 1990, 1987, Fast et al. 1987, Mas et al, 1987; Sherman et al. 1987, Grieve 1986, Dvorak and Orelli 1985, Gotlib and Thiel 1985, Schmidley and Koch 1984, Gutmann 1983, Gatterman 1981, Ladermann 1981, Jaskoviak 1980, Kleynhans 1980, Krueger and Okazaki 1980, Schellhas et al. 1980, Livingston 1971). This interest suggests that the elevated level of reporting arises from a general increase in awareness by all professionals interested in spinal manipulative therapy. Some alleged consequences are consistent with the natural history of a condition and thus, anecdotal or polemic reports must be distinguished from those which provide objective evidence of true manipulation-induced injuries. Some case reports of injury have proven to be unfounded upon further unbiased inquiry.

Complications that do occur in a chiropractic office setting may be attributed to the following (Shekelle et al, 1991):

• misdiagnosis
• presence of coagulation dyscrasias
• cervical manipulation
• presence of a herniated nucleus pulposus
• improper technique application

• disc problems - 29%
• failure to diagnose - 13%
• fracture - 9%
• soft tissue injury - 7%
• cerebrovascular accidents - 6%
• aggravation of prior condition - 4%

Lumbar spine injury 36 (23% of claims)

Rib fracture 29 (19%)

Soft tissue/non-spinal injury 26 (13%)

Cervical spine injury 24 (16%)

Cerebrovascular accidents 12 ( 8%)

Thoracic spine injury 8 ( 5%)

*Other 24 (16%)

(*fee dispute, patient perception of general injury, failure to diagnose, improper treatment, practitioner concern over lawsuit)

With respect to the frequency of complications, Ladermann (1981) identified 135 case reports of serious complications over a thirty year period between 1950 and 1980. During this time period, tens of millions of manipulations were administered by a variety of practitioners. Kleynhans (1980), analyzing some of these case studies, outlined a number of likely practitioner-related causes of adverse reactions. Three main factors were identified: lack of knowledge or diagnostic error, lack of technique skill, and lack of rational clinical attitude in case management. These causes may well have accounted for a number of the iatrogenic injuries reported in the literature, e.g., pathological fractures (Austin 1985, Holta 1942), ruptured abdominal aneurysms (Kornberg 1988), and sensorineural hearing loss (Brownson et al. 1986).

Terrett (1987) and Jaskoviak (1981) specifically dealt with case reviews on the adverse effect of cervical manipulation where vertebrobasilar insufficiency was evident. Schmitt (1991), Thiel (1991), Terrett (1987), and Gutmann (1985) have recently described or studied the biomechanical effects of head and neck movement and cervical manipulation in association with vertebral artery injury. Manipulation has been identified as one of many activities or health care procedures that may result in damage to the vertebral artery. However, manipulation in association with vertebral artery injury has been the most extensively reviewed and discussed (Henderson 1992, 1979, Raskind and North 1990, Frumkin and Baloh 1990, Martienssen and Nilsson 1989, Henderson and Cassidy 1988, Fast et al. 1987, Terrett 1987, 1983, 1982, Gutmann 1985, 1971, 1962, 1959, Hulse 1983, George et al. 1981, Giles 1977, Houle 1972, Lewit 1972, Maigne 1969, Smith and Estridge 1962, Pratt-Thomas and Berger 1947).

It is thought that cervical rotation combined with extension and traction may have some obstructive effect on perfusion of the vertebral artery. Several studies suggest that the vertebral artery on the contralateral side of rotation comes under partial physiological compression (Thiel 1992, Schmitt 1991, Andersson et al. 1970, Selecki 1969, Toole and Tucker 1960). If the ipsilateral artery is diseased or hypoplastic, symptoms of hind brain ischaemia may occur as a result of a loss of sufficient or compensatory blood flow. A recent study suggests that cervical rotation combined with extension and traction may in fact obstruct flow in either vertebral artery (Koskas et al. 1992). If trauma to the arterial wall does occur, thrombus formation may be the result. Further, this may lead to stroke or stroke-like complications in susceptible patients. While incidence figures vary, it is generally agreed that the risk of serious neurological complication is extremely low and is approximately 1 or 2 per million cervical manipulations (Henderson 1992, Terrett 1987, Dvorak and Orelli 1985, Gutmann 1983, Jaskoviak 1980). Structural abnormalities particularly where mechanical instability, pathological bone disorders, dislocations and fractures of the cervical spine are present may also lead to mechanical injury of the vertebral arteries (Terrett 1987, Jaskoviak 1981, Ladermann 1981, Kleynhans 1980).

Other cervical manipulative complications, which are rare but have either been reported or described in the literature include diaphragmatic paralysis, cervical myelopathy secondary to meningeal haemorrhage, pathological fracture of a cervical vertebra and cervical disc protrusions (Gatterman 1991, Grayson 1987, Heffner 1985, Kewalramani et al. 1982, Rinsky et al. 1976, Dabbert et al. 1970). Instability in the upper cervical spine due to inflammatory or traumatic rupture of the transverse, atlantal or alar ligaments warrant special consideration in susceptible patients (Yochum and Rowe 1987, 1980, Redlund-Johnell 1984, Sandman and Sandman 1981, Jeffreys 1980). Atlanto-axial instability is suggested when the distance between the posterior aspect of the anterior arch of the atlas and the anterior aspect of the odontoid process exceeds 3mm in adults or 5mm in young children, or an osseous distance that changes considerably between flexion and extension (Chapman and Nakielny 1984). Besides inflammatory arthritis and trauma, atlanto-axial instability can also be present in congenital anomalies such as os odontoideum in patients with Down's, Morquio's, or Klippel Feil syndromes.

Though rarely reported in the literature, empirically the most common sequelae of manipulation to the thoracic region occurs when forceful or poorly applied manipulations cause costovertebral sprains, rib fractures and/or costochondral separations (Haldeman 1993, Grieve 1986). Excessive thoracolumbar torque in the lateral recumbent position as well as inappropriately applied posterior to anterior techniques may also cause thoracic cage injuries, particularly in the elderly.

Low-back injury alleged to have occurred following spinal manipulative therapy has been reported in patients with pre-existing disc herniation or prolapse (CCPA Claim Review 1990; Bromley 1989, Gallinaro and Cartesegna 1983). While it is suggested that the forces required to cause a disruption of the annular fibres of the healthy intervertebral disc well exceed that of a rotational manipulative thrust (Cassidy et al. 1993), Triano 1991, Gilmore 1986, Farfan 1983, Adams and Hutton 1983, 1981), some disc herniation/protrusions may be aggravated by an inappropriately applied manipulative manoeuvre as it may be by other simple activities of daily living such as bending, sneezing, and/or lifting. Manipulation as a form of treatment of patients with lumbar disc herniation is used by chiropractors. There are several uncontrolled descriptive studies and single case reports of the successful treatment of lumbar disc herniation by manipulation (D'Ornano et al. 1990, Quon et al. 1989; Martin 1988, Kuo and Loh 1987, Chrisman et al. 1964, Mensor 1955, Henderson 1952). There is only one controlled clinical trial which compared oscillatory rotational manipulation to conventional physiotherapy in the treatment of lumbar disc herniation. The results favoured the manipulated group on all outcome measures (Nwuga 1982).

In most cases of lumbar disc herniation, the effect of manipulation is to help relieve back pain; to allow for improved ambulation and thus offer greater comfort to the patient (Cassidy et al. 1992). Manipulation for lumbar disc herniation when appropriately applied is a safe treatment in cases where there are no signs of increasing neurological deficit or cauda equina syndrome (Cassidy et al. 1993).

The most frequently described severe complication is compression of the cauda equina by massive midline nuclear herniation at the level of the third, fourth or fifth intervertebral disc (Lehmann et al. 1991, Malmivaara and Pohjola 1982, Kleynhans 1980, Hooper 1973). Of the twenty-nine cases of cauda equina syndrome associated with manipulation collected in the French, German and English literature reported over a period of 80 years, only eight were allegedly related to chiropractic treatment (Haldeman and Rubinstein 1992, Ladermann 1981). In most cases it was impossible to determine whether manipulation was a precipitating factor or merely coincidental to the onset of cauda equina syndrome. Had these patients not been manipulated, the outcome may have been the same with menial effort or impulsive strain replacing the rupturing effect allegedly to have arisen from the manipulation. However, until further conclusive evidence is available, this clinical outcome does stress the need for particular care in this susceptible sub-group of patients.

Complications may occur spontaneously or arise as a result of chiropractic treatment. The risk of these complications may vary within subgroups of patients based on their clinical presentation. The main focus for the prevention of complications is the recognition of well-known and established indicators or "red flag" signs and symptoms which may require careful assessment and reassessment, changes in treatment plan, or other appropriate action, such as emergency care or referral to another health care specialist. Ignoring these "red flag" indicators increases the likelihood of patient harm.

When assessing whether any particular therapeutic procedure is safe and effective, two major interdependent factors require consideration: the patient's overall condition in association with the specific complaint for which the patient sought care and secondly, the risk associated with the application of a therapeutic procedure in any given situation.

The literature and clinical experience suggest that the most common therapeutic procedure in chiropractic practice, and the one most likely to result in complications, is the adjustment or high-velocity manipulative thrust. The following assessment criteria and recommendations relate to this procedure applied to, or adjacent to, the anatomical site of pathology.

Assessment criteria developed and used in this chapter relate to:

A) Severity of complication.

B) Rating of a condition.

C) Quality of evidence.

D) Level of contraindication - based on the above three factors.

A. Severity of Complication:

Minimal Level:

Minor or temporary intensification of symptoms may occur following high-velocity thrust procedures. These reactions are rarely reported in the literature/claim reviews, given the brief duration of mild symptoms experienced by patients and the superimposed natural history of the presenting complaint. Generally, there is no contraindication to high-velocity thrust procedures.

Moderate Level:

Level of harm is generally moderate, characterized by fairly serious, but usually reversible harm lasting weeks to months. Effects are temporary and/or residual in nature (e.g., broken rib, uncomplicated disc herniation, radiculopathy, foot drop). Depending on all factors (e.g., frequency of complications, benefits) high-velocity thrust procedures may be relatively or absolutely contraindicated.

High Level:

Evidence suggests that there may be a high level of risk of harm. The complication or accident may be serious and/or permanent, particularly in susceptible patients (e.g., stroke, cauda equina syndrome). Serious complications are rare but perhaps under-reported in the literature. High-velocity thrust procedures may be relatively contraindicated requiring careful treatment modification or absolutely contraindicated given patient history, diagnostic tests and/or other information obtained during a trial of therapy.

B. Rating of Conditions:

Type I Condition:

A condition for which a high-velocity thrust procedure has been shown to be comparatively safe and effective so long as an adequate diagnosis or clinical impression has been made and a therapeutic trial is rationally applied (e.g., upper cervical dysfunction associated with tension headaches).

Type II Condition:

A Type I condition is present but may be coincident with another related or unrelated condition requiring modification of a therapeutic procedure and/or further diagnostic assessment (e.g., lumbar spine joint dysfunction associated with a Grade 2 spondylolisthesis). Careful clinical judgment is required as high-velocity procedures may be relatively or absolutely contraindicated.

Type III Condition:

Type I or II conditions are present but considered negligible compared with clinical evidence of another pathological problem requiring further diagnostic assessment and referral to another health care professional or specialist (e.g., cervical joint dysfunction and local metastatic bone tumour). As the risk of serious harm far outweighs benefit, the therapeutic procedure may be absolutely contraindicated.

C. Quality of Evidence:

Evidence on the risk of complication arising from chiropractic treatment, particularly high-velocity thrust procedures comes from case reports, surveys, literature reviews, and insurance and legal claim records. There needs to be further systematic study of the incidence, severity and management of complications. Present classification of quality of evidence is:

Class I:

Evidence provided by well-designed prospective studies such as randomized controlled trials, cohort studies, and case-control studies published in refereed journals.

Class II:

Evidence provided by surveys, systematic studies, literature reviews, and detailed clinical case reports, or consensus expert opinion from legitimate consensus-building efforts published in refereed journals.

Class III:

Evidence provided by expert opinion and one or more case reports.

D. Level of Contraindication:

Having regard to all of the individual assessment criteria already discussed, the following overall ratings are used:

No Contraindication.

Relative Contraindication - high-velocity thrust procedures may be used with appropriate care and/or modification.

Relative to Absolute Contraindication - careful clinical judgment dictates whether contraindication is relative or absolute with each individual patient.

Absolute contraindication.

Example: As an example of the complete rating system for non-complicated mechanical low-back pain: no contraindication to high-velocity thrust procedures.

Risk-of-Complication Rating:

Severity (if harm did occur): Minimal

Condition Rating: Type I

Quality of Evidence: Class I

This rating system assumes no negligence or error on the part of the practitioner. Tolerance to treatment may sometimes, but not always, be estimated by provocative or pre-manipulative testing.

In the following examples it is assumed that traditional and commonly used high-velocity, low-amplitude thrusts (manipulation/adjustment) are administered to, or immediately adjacent to, the segmental level where the manipulable lesion (joint dysfunction, subluxation) has primarily manifested itself.

NOTE: General health problems which have been described in the literature as either contraindications to or complications of high-velocity thrust procedures include the following conditions. It should be understood that the manipulative procedures are not necessarily intended for the following listed conditions. Rather they may be co-incidentally present in a patient undergoing treatment. The fundamental object of treatment is a manipulable lesion (subluxation, joint dysfunction, functional spinal lesion).

A. Articular Derangement:

1. Arthritides

13.1 Inflammatory arthritis such as rheumatoid arthritis, seronegative spondyloarthropathies including acute ankylosing spondylitis characterized by episodes of acute inflammation, demineralization, ligamentous laxity with anatomic subluxation or dislocation, represent an absolute contraindication to high-velocity thrust procedures in anatomical regions of involvement.

Risk-of-Complication Rating:

Severity: Moderate to High

Condition Rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

13.2 Sub-acute and chronic ankylosing spondylitis and other chronic arthropathies in which there are no signs of ligamentous laxity, anatomic subluxation or ankylosis are not contraindications to high-velocity thrust procedures applied to the area of pathology.

Risk-of-Complication Rating:

Severity: Minimal

Condition Rating: Type I, II

Quality of Evidence: Class III

Consensus level: 1

13.3 Degenerative joint disease, osteoarthritis, degenerative spondyloarthropathy and facet arthrosis are not contraindications to high-velocity thrust techniques to the area of pathology but treatment modification may be warranted during active inflammatory phases.

Risk-of-Complication Rating:

Severity: Minimal

Condition Rating: Type I, II

Quality of Evidence: Class II

Consensus Level: 1

13.4 In patients with spondylolysis and spondylolisthesis caution is warranted when high-velocity thrust procedures are used. These conditions are not contraindications, but with progressive slippage, they may represent a relative contraindication.

Risk-of-Complication Rating:

Severity: Minimal to Moderate

Condition Rating: Type I, II

Quality of Evidence: Class II

Consensus Level: 1

13.5 Fractures and dislocations, or healed fractures with signs of ligamentous rupture or instability, represent an absolute contraindication to high-velocity thrust procedures applied to the anatomic site or region.

Risk-of-Complication Rating:

Severity: High

Condition Rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

13.6 Atlanto-axial instability represents an absolute contraindication to high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: High

Condition Rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

13.7 Articular hypermobility, and circumstances where the stability of a joint is uncertain, represent a relative contraindication to high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: Moderate

Condition Rating: Type I, II

Quality of Evidence: Class III

Consensus Level: 1

13.8 Post-surgical joint or segments with no evidence of instability are not a contraindication to high-velocity thrust procedures but may represent a relative contraindication depending on clinical signs (e.g., response, pre-test tolerance or degree of healing).

Risk-of-Complication Rating:

Severity: Minimal

Condition Rating: Type II

Quality of Evidence: Class III

Consensus Level: 1

13.9 Acute injuries of joint and soft tissues may require modification of treatment. In most cases, high-velocity thrust procedures to the area of pathology are not contraindicated.

Risk-of-Complication Rating:

Severity: Minimal to Moderate

Condition Rating: Type I, II

Quality of Evidence: Class I, II

Consensus Level: 1

13.10 The presence of a scoliosis is not a contraindication to high-velocity thrust procedures.

Risk-of-Complication Rating:

Severity: Minimal

Condition Rating: Type I, II

Quality of Evidence: Class II, III

Consensus Level: 1

B. Bone Weakening and Destructive Disorders

13.11 Active juvenile avascular necrosis, specifically of the weight bearing joints (e.g., Legg-Perthes disease) represents an absolute contraindication to high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: High

Condition Rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

13.12 Demineralization of bone warrants caution. This represents a relative contraindication to high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: Minimal to Moderate

Condition Rating: Type II

Quality of Evidence: Class III

Consensus Level: 1

13.13 Benign bone tumours may result in pathological fractures and therefore represent a relative to absolute contraindication to high-velocity thrust procedures to the area of pathology. Tumour-like and dysplastic bone lesions may undergo malignant transformation or weaken bone to the point of pathological fracture and therefore represent a relative to absolute contraindication to high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: Minimal to Moderate

Condition Rating: Type II, III

Quality of Evidence: Class III

Consensus Level: 1

13.14 Malignancies, including malignant bone tumours, are conditions for which high-velocity thrust procedures to the area of pathology are absolutely contraindicated.

Risk-of-Complication Rating:

Severity: Moderate to High

Condition rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

13.15 Infection of bone and joint represents an absolute contraindication to high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: High

Condition Rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

C. Circulatory and Cardiovascular Disorders

13.16 Clinical manifestations of vertebrobasilar insufficiency syndrome warrant particular caution and represent a relative to absolute contraindication to cervical high-velocity thrust procedures to the area of pathology.

Risk-of-Complication Rating:

Severity: Minimal to High

Condition Rating: Type II, III

Quality of Evidence: Class II

Consensus Level: 1

13.17 When a diagnosis of a significant aneurysm involving a major blood vessel has been made, a relative to absolute contraindication may exist for high-velocity thrust procedures within the area of pathology.

Risk-of-Complication Rating:

Severity: High

Condition Rating: Type III

Quality of Evidence: Class III

Consensus Level: 1

13.18 Bleeding is a potential complication of anticoagulant therapy or certain blood dyscrasias. These disorders represent a relative contraindication to high-velocity thrust procedures.

Risk-of-Complication Rating:

Severity: Minimal to High

Condition Rating: Type II

Quality of Evidence: Class III

Consensus Level: 1

D. Neurological Disorders

13.19 Signs and symptoms of acute myelopathy or acute cauda equina syndrome represent an absolute contraindication to high-velocity thrust procedures.

Risk-of-Complication Rating:

Severity: High

Condition Rating: Type II, III

Quality of Evidence: Class II

Consensus Level: 1

* Most dysfunctions or disease processes have variations or phases. In assigning gradations of severity, it is assumed that the condition is characteristic of the average or common classical signs and symptoms. The difficulty in precisely detailing the degree of severity of an individual patient's overall physical and psychological response both to the disease process and therapeutic procedure itself (subtleties of force, amplitude, direction, patient positioning, etc.) is acknowledged; nevertheless, a rating has been assigned based on results of returned surveys and the available literature. This will provide a basis or starting point from which to fine tune future recommendations arising from discussion at the consensus conference.

This chapter provides an analytical framework and specific interim guideline recommendations with respect to complications of and contraindications to manipulative thrust procedures. At present detailed systematic studies on this subject are lacking and the recommendations made are based on information from clinical reviews and case reports, as well as from expert and consensus methods. One objective of this chapter is to encourage productive debate leading to firmer commitment on risk management protocols.

Recommendations made must be continuously re-evaluated in light of ongoing research and clinical experience. Co-operative intradisciplinary and interdisciplinary research will be necessary to determine the true extent of the nature and incidence of iatrogenic complications in chiropractic practice. The development of a central registry system capable of generating comprehensive research data would be valuable, and would facilitate the establishment of more detailed and refined guideline recommendations in the future.

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