The Immediate Extent of the Hypoalgesic Effect Following Central Mobilisations to L3, L4 and L5
Phase: NA
Conditions: Low Back Pain
Sponsor: Darren Cooper

The Immediate Extent of the Hypoalgesic Effect Following Central 
Mobilisations to L3, L4 and L5. 
 
October 27th 2023 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Study Protocol 
Study Design 
The design of the study was a randomised, single-blind, repeated measures, cross-over design, 
performed in a single-centre environment. Ethical approval was gained from the School of Sport and 
Exercise Science ethics committee at the University of Worcester (ISES2018RF1). Informed consent 
was gained from each participant before testing. 
 
Sample and Inclusion Criteria 
The study included twenty asymptomatic participants (11 females and 9 males); the mean age of the 
participants was 21.9 years (±2.67, range 20- 30). A health questionnaire (based on the PARQ) was 
completed by each participant to establish any contraindications they may have to the experimental 
procedures, namely the application of vertebral mobilisations. No participants were required to be 
excluded as none of them had consulted their doctor in the last six months, were taking any 
medication, had an infection in the past two weeks, had no heart, asthma, diabetes, bronchitis, 
epilepsy or blood pressure issues, had any current muscle or joint injury, were able to train/exercise 
normally or knew of any other reason that would preclude them from participating. 
 
Data Collection 
Each participant was randomly assigned using a random number generator to the order in which their 
lumbar vertebral levels were mobilised and to the order of each dermatome level tested for the 
baseline and all three mobilisation interventions.  
Before initiating the experimental procedure, the participant’s age, height, and weight were recorded. 
The participant was instructed to lay on their back, on the plinth and had the five locations for 
dermatome testing marked with a water-soluble pen. The researchers utilised the method of using 
participant’s finger breadth to establish dermatome testing sites (Gross et al 2015) the dermatome 
testing sites were based on Keegan and Garrett’s dermatome map (Keegan & Garrett, 1948) see 
Figure 1. From this point forth, the spinal levels will be referred to as L2 or L3, respectively and the 
corresponding dermatome of the vertebral level will be referred to as DL2 or DL3. 
 
Figure not included due to copyright reasons. 
 
Figure 1.  The dermatome map was established originally by Keegan & Garrett (1948). DL2 landmark- 
4 participant’s finger breadth inferior from ASIS, mid anterior thigh. DL3 landmark- 8 participant’s 
finger breadth inferior from DL2 landmark, mid anterior thigh. DL4 landmark- 2 participant’s finger 
breadth superior from the proximal border of the patella, mid-way. DL5 landmark- 4 participant’s finger 
breadth inferior from tibial tuberosity, then 1 participant’s finger breadth lateral (so that the landmark is 
on the tibialis anterior, not tibia). S1 landmark- 1 participant’s finger breadth inferior to the lateral 
malleolus. Adapted and used with permission from Anatomical Record. 1948;102(4):409. 
 
Once these locations were marked on the participant's left leg, a demonstration of the Neuropen® 
(Owen Mumford, Oxfordshire, UK) was performed on the participant's hand (opposite to the side 
being tested). Once all this had been completed, baseline measures were taken. Using the 
Neuropen®, a standardised force of 40g was applied to one of the locations. The participant then 
received a small piece of card with a vertical 10cm visual analogue scale (VAS) line on it and a pen 
and was asked to "draw a horizontal line on the scale to indicate how much sensation you feel, 0 
being can-not feel anything and 10 being an extremely strong sensation". Following this explanation, 
the participant was asked if they understood and whether they needed further instruction to complete 
the VAS card. Once the participant marked the card, the card and pen were collected and stored, this 
process was repeated with the remaining four locations (these five cards provided the baseline data). 
A new tip was used for each participant, and a decrease in PPS represents a reduction in pain. 
Once baseline measurements were collected by the lead researcher, the participant was asked to turn 
onto their front; the first (pre-determined) lumbar vertebra was found using the iliac crest as an 
anatomical landmark for the differentiation test. When the correct vertebra was located, the 
experimenter pressed record on the laptop connected to the PGD plinth (see Cooper et al (2018) for 
full details) to record the force applied and calculate the frequency. 
The lumbar vertebra was mobilised using Maitland's vertebral mobilisation method for posterior-
anterior central vertebral pressures (PACVPs) for four sets of 30 seconds (Pentelka et al 2012) with 
up to 30s between each, at a grade III amplitude (Maitland et al 2005) and a target rate of 3Hz 
(Piekarz & Perry 2015) to ensure the total time for testing was less than fifteen minutes in duration, 

before the opioid system is activated (Beatti et al 2010). Once the fourth 30-second mobilisation had 
been completed, the researcher pressed stop on the laptop and asked the participant to roll onto their 
back. Then the next five sets of data were collected following the same procedure implemented for 
the baseline measures (collected in a different, pre-determined order each time). This process was 
repeated for the remaining two vertebrae.  
 
Statistical Analysis Plan 
A Multivariate Analysis of Variance (MANOVA) for individual levels against baseline and a One-way 
Analysis of Variance (ANOVA) for the collated (data set reduced to identify effects at either the same 
vertebral level as treated versus baseline, one, two or three above or below respectively) mobilisation 
effect including Tukey post hoc tests for both were conducted using IBM SPSS statistics 25, p values 
less than 0.05 were defined as acceptable. Effect sizes identifying Cohens d (Large 0.8, Medium 0.5, 
and Small 0.2) and Magnitude Based Inferences (MBI) were also calculated for each a more 
comprehensive analysis of the data.