Issues in physical examination, diagnostics, reliability and validity

Assessment and treatment for sacroiliac dysfunction is common in manual therapy management for spinal pain and is based on the assumption that small movements occur at the sacroiliac joints (SIJ). SIJ dysfunction is often addressed using manipulation techniques, usually involving the application of manual forces to the joint complex. Considering the fact many of these treatments rely on the hypothesis that SIJ motion is directly alterable by such forces it is important for practitioners to be aware that producing movement at the SIJ may not be possible in many individuals due to the presence of joint fusion.

Dar et al.1 have recently conducted a study with aim of determining the prevalence of SIJ fusion using 3-D CT imaging. The study examined 287 consecutive patients (159 male, 128 female) referred to a hospital radiology department for a variety of abdominal complaints. The patients ranged from 22-93 years. Patients with spinal diseases, such as spondyloarthropathy and diffuse idiopathic hyperostosis (DISH), were excluded. Unfortunately, information on low back pain status was not reported. 3-D images of pelvises were obtained using a 64-slice CT scanner, and volume rendering sections of 1-2mm thickness. Multiplanar reformation was used to detect whether the fusion was intra- or extra-articular. The SIJs of each image were divided into six equal areas and the presence, side and location of fusions were recorded. Assessment was made by two radiologists who were blind to each others results and the interexaminer agreement was substantial.

SIJ fusion was found in 16.7% of subjects and was far more prevalent in males (27.7%) than females (2.3%). All fusions were extra-articular. Fusion in males was strongly correlated with age: 5.6% in the 20-39y.a. cohort, 15.85% in the 40-59y.a. cohort, 31.1% in the 60-79y.a. cohort, 46.7% in individuals aged over 80. Fusion among females was not significantly correlated with age. Fusion was present bilaterally in 11.9% of males. Diffuse fusion was present in 7.5% of males, four cases were bilateral. The superior region was involved in all male individuals manifesting the phenomenon. No fusions were isolated to the inferior part of the joint. Fusion of the females was at just above and under the arcuate line at the most anterior point of the joint.

The results of this study accord with previous skeletal and cadaver studies and demonstrate that SIJ fusion is common. Further, it is clearly an age and gender biased phenomenon. The authors suggest that osteopaths and other manual therapists who frequently utilise manipulation techniques aimed at addressing sacroiliac articular mobility or that result in forces across the sacroiliac joint should be aware of the limited potential for compliance at this joint in older males. The risk of injury may be far greater than the potential benefits of manually applied forces during the treatment of SIJ dysfunction in this population.

1.    Dar G, Khamis S, Peleg S, Masharawi Y, Steinburg N, Peled N, Latimer B, Hershkovitz I. Sacroiliac joint fusion and the implications for manual therapy diagnosis and treatment. Manual Therapy. 2008;13:155-58.

Non-specific low back pain (NS-LBP) is commonly conceptualised, categorised and treated as inflammatory and/or mechanical in nature. There is no universally accepted definition for mechanical or inflammatory LBP, however, there is evidence to support the involvement of both mechanical and inflammatory factors in its generation. Following from this nosological separation, there are two distinct approaches to treatment for LBP: treatment involving “mechanical” intervention, such as mobilisation, manipulation, traction and exercise are contrasted with ‘‘anti-inflammatory’’ treatments like non-steroidal anti-inflammatory medications and corticosteroid injections.

In an effort to identify common symptoms or signs that may allow discrimination between inflammatory low back pain (ILBP) and mechanical low back pain (MLBP), Walker and Williamson recently surveyed experienced health professionals from five professions using a questionnaire listing 27 signs/symptoms. Of 129 surveyed, 105 responded (81%). According to their results, constant pain, pain that wakes, and stiffness after resting  were generally considered as moderate indicators of inflammatory LBP. Intermittent pain during the day, pain that develops later in the day, pain on standing for a while, pain bending forward a little, pain on trunk flexion or extension, pain doing a sit up, pain when driving long distances, pain getting out of a chair, and pain on repetitive bending, running, coughing or sneezing were all generally considered as moderate indicators of MLBP. There was, however, no consistency of agreement either between or within professional groups.

While the general absence of agreement regarding signs and symptoms of ILBP and MLBP does not invalidate the pathophysiological paradigms of mechanical and inflammatory pains, it does, however, signal the need for further research. This research should be aimed at testing the indicators identified in this study for their ability to predict the outcome of mechanical and anti-inflammatory treatments of LBP.

Walker BF, Williamson OD. Mechanical or inflammatory low back pain. What are the potential signs and symptoms? Man Ther. 2009 Jun;14(3):314-20. Epub 2008 Jun 13.

Myofascial trigger points (MTPs) are routinely diagnosed and treated by clinicians in many musculoskeletal health disciplines. MTPs have been associated with numerous clinical conditions and prevalence studies claim that they may account for 30-85% of patients complaining of regional muscular pain.1 Despite the widespread acceptance of MTPs as an important clinical entity the diagnosis of MTPs is a source of continuing controversy. There are no accepted biochemical, electromyographic or diagnostic imaging criteria recognised as a definitive diagnostic gold standard.2 Furthermore, there is currently no reliable list of physical diagnostic criteria for MTPs.1 The detection of MTPs is solely dependent on manual palpation and patient feedback. These circumstances have raised concerns regarding the non-substantive manner in which MTPs are identified.

In the absence of an accepted gold standard, physical diagnostic tests should demonstrate inter-rater reliability in order to be considered clinically useful. Myburgh et al.3 have recently published the first systematic review of reliability studies examining evidence for the use of manual palpation for identifying MTPs. The reviewers used a comprehensive search strategy across relevant medical databases and the reference lists of related articles. The search revealed eleven relevant studies, however five studies were subsequently excluded because they did not use appropriate statistical measures of agreement. The remaining six studies were then assessed for internal validity and reproducibility according to predetermined quality criteria.

The included studies examined the use of manual diagnosis for MTPs in a variety of settings, populations, conditions and clinicians. This heterogeneity limited pooled analysis of the results. In addition, none of the studies used completely overlapping diagnostic criteria, and no single muscle was observed in more than two studies. The results of the quality analysis indicated two studies to be of high quality, one of moderate quality, and three of low quality.  None of the MTP criteria were found to have a high level of evidence. At best, the current literature suggests moderate evidence for the reliability of local tenderness in the trapezius, and pain referral at gluteus medius and quadratus lumborum; however a single reliable criteria is insufficient to diagnose a MTP according to commonly cited diagnostic criteria. The authors concluded that the current evidence supporting the reliability of diagnostic palpation for MTPs is weak and further high quality studies are required.

The clinical uncertainties surrounding MTP diagnosis present challenges to the interpretation of all research on MTPs. In the absence of an accurate diagnosis, the results of any epidemiological, pathophysiologic or clinical investigation will be misleading.1 A potent example of this is seen in the subsequent issue of the same journal, where Ettlin et al.4 report on the prevalence of cervical MTPs in four different clinical populations and a group of healthy controls. Having assumed that identification of each of the MTP characteristics is reliable, the researchers state that a clinically relevant MTP was present if three out four listed criteria were met. However, using this methodology it is possible that the diagnostic process would identify presentations other than MTPs, such as non-specific muscle pain, pain of peripheral nerve trunk origin, underlying joint sensitivity, secondary hyperalgesia, or even normal intramuscular physiology. It also explains their report of active MTPs in up to one third of the pain-free controls, which should be considered impossible considering that active MTPs are symptomatic by definition.

Until both consensus and reliability of diagnostic criteria for identifying MTPs are achieved and implemented in research studies, data on the validity, prevalence, aetiology and treatment of MTPs should be interpreted with prudence.

1. Tough EA, White AR, Richards S, Campbell J. Variability of criteria used to diagnose myofascial trigger point pain syndrome: Evidence from a review of the literature. Clinical Journal of Pain 2007;23:278-286.
2. Rickards LD. The effectiveness of non-invasive treatments for active myofascial trigger point pain: a systematic review of the literature. International Journal of Osteopathic Medicine 2006;9:120-136.
3. Myburgh C, Larsen AH, Hartvigsen J. A systematic, critical review of manual palpation for identifying myofascial trigger points: Evidence and clinical significance. Archives of Physical Medicine and Rehabilitation 2008;89:1169-1176.
4. Ettlin T, Schuster C, Stoffel R, Brüderlin A, Kischka U. A distinct pattern of myofascial findings in patients after whiplash injury. Archives of Physical Medicine and Rehabilitation 2008;89:1290-93.