Research Review Corner: December 2010

Results:

Disc degeneration did not differ between twins who reported previous back injury and their uninjured twins. This finding was consistent for both disc height and disc signal intensity regardless of whether mean scores or greatest difference at any one lumbar level was used in the analysis. There was also no evidence that a greater period since an injury resulted in greater twin differences in disc degeneration.

Comments:

The current study suggests that back injury based on patient report is not an important predictor of future disc degeneration. In recent years, beliefs regarding the determinants of disc degeneration have changed dramatically. It was previously thought that the primary determinants of disc degeneration included age, gender, cigarette smoking, exposure to vehicular vibration and, in particular, occupational physical loading. More recently, it has been demonstrated that most of these factors have, at most, a relatively minor influence on disc degeneration. In fact, routine loading may actually have some benefits for the lumbar discs in terms of slowing desiccation.  Even though genetic factors seem to be the most consistent influence on disc degeneration, there is still much to be learned. 

Study #2: Age and lumbar ROM

Publication Information:  Intolo P et al. The effect of age on lumbar range of motion: A systematic review. Manual Therapy 2009; 14:596-604.

Summary:

This systematic review examined the evidence on the effect of age on lumbar ROM in healthy subjects.

Results: 

Sixteen studies met inclusion criteria and were analyzed by the authors.  These studies suggest that age-related reductions occur in flexion (more in males), extension and lateral flexion particularly from 40 to50 and after 60 years of age. There was very little age effect on lumbar rotation.  Overall, there is strong evidence for a non-linear age-related reduction in lumbar sagittal and coronal ROM after 40 years of age that also appears to be asymmetric in the coronal plane. These factors should be considered during the evaluation of spinal ROM in patients who present with lumbar disorders.

Comments: 

The results of this study remind clinicians to consider the age of their patients when assessing lumbar ROM, or using it as an outcome during the course of treatment.  It should be noted that this study could not elucidate whether decreases in lumbar ROM are inevitable or irreversible, or make inferences on other biomechanical characteristics of the aging spine.   

Study #3: Migraine headache and CROM in women

Publication Information: Belivaqua-Grossi D et al. Cervical mobility in women with migraine. Headache 2009; 49: 726-731.

Summary:

The aim of this study was to contrast the cervical range of motion (CROM) in women with episodic migraine (EM), transformed migraine (TM), and migraine-free controls (45 total subjects, 15 in each group). It is well known that migraineurs often complain about neck pain. Furthermore, neck problems can worsen the headaches in individuals with migraine. Individuals with neck pain usually have reduced CROM. To date, there is little research assessing the CROM in migraineurs.

Results:

Compared with controls, individuals with TM had numerically inferior CROM in all parameters, and significant reduction in extension, left lateral flexion and right rotation.  Compared with individuals with migraine, the TM group presented significantly reduced mobility only for extension.  Migraineurs also had numerically inferior ROM, contrasted to controls, in five of the six parameters, although significance was seen just for right rotation. There was no correlation between cervical mobility and migraine parameters. The CROM was not reduced for the symptomatic side of migraine, in cases of unilateral pain.

Comments: 

Although this was a small study, the results suggest that women with episodic or transformed migraine have reduced cervical ROM compared to controls.  Since many migraine patients also report neck pain, and a common goal of manual therapists is to restore ‘normal’ ROM, future research will hopefully examine if there is cause and effect relationship between ROM and migraine that we could positively influence with treatment.