Sunday, October 30, 2022

Is It Really Your Piriformis?

A patient came in to our clinic this week complaining of deep buttock pain and sciatica - pain along the path of the sciatic nerve, the largest nerve in our bodies.
The sciatic nerve starts from the lower back through the hips and buttock down the back of our leg. See picture above.

The sciatic nerve usually travels from within the hip to the deep gluteal space (buttocks) via the greater sciatic notch. It's pathway is most commonly beneath the piriformis muscle (90 percent). Sometimes it goes through the piriformis muscle (7 percent). See picture below.

Right Piriformis muscle and the sciatic nerve

Because of this, the pirifomis muscle is often blamed to be the cause of the pain, which is known as piriformis syndrome.
The nerve then travels over the obturator internus muscle and gemellus superior, inferior muscles (gemellei) to exit that area. Picture above.

The sciatic nerve can get encroached or irritated by the piriformis and adjacent structures in that deep gluteal space which may result in pain at the area of irritation or along the path of the sciatic nerve - this is true sciatica pain.

After assessing my patient, there was no pain nor tenderness in her piriformis. Instead, her obturator internus reproduced her buttock pain. 

Coincidently, I was fortunate to have read a recently published article exploring the relationship of the sciatic nerve and the deep hip external rotator muscles in the deep gluteal space (Balius et al 2022).

The authors recruited 58 healthy volunteers, 30 males and 28 females with an average age of 20.4 years plus or minus 7 years using real time ultrasound to quantify nerve action.

The sciatic nerve was found to be compressed (and moved forward and laterally) during passive hip internal rotation and isometric external rotation contraction (obturator internus and gemelli muscles working). Not the piriformis muscle, which the authors wrote were often over diagnosed.

During passive hip external rotation and isometric contraction of internal hip rotators, the sciatic nerve moved back into place and medially.

The obturator internal-gemellus syndrome may be a more accurate term than piriformis syndrome for my patient. 

Interestingly, the same lead author, Balius and colleagues, published an earlier article in 2018 where they studied 6 fresh cadavers and 31 healthy volunteers. This study revealed the presence of connective tissue (or fascia) attaching the sciatic nerve to the obturator internus-gemellus tendons. The sciatic nerve was also affected similarly in the cadavers and subjects during passive hip internal rotation. 

This newer study (Balius et al, 2022) provides further evidence that stretch or contraction of the obturator internus-gemellei complex will create some compression of the sciatic nerve at this level in the deep gluteal space. Definitely worth considering for those with buttock pain and sciatica.

The next time you have buttock pain or sciatica and the health practitioner treating you tells you that you have piriformis syndrome you may suggest it's not always the piriformis ;)


Balius R, Pujol M, Perez-Cuenca D et al (2022). Sciatic Nerve Movements In the Deep Gluteal Space During Hip Rotations Manuevers. Clinical Anatomy. 35(4): 482-491. DOI: 10.1002/ca.23828

Balius R, Sussin A, Morros C et al (2018). Gamellei-obturator Complex In the Deep Gluteal Space: An Anatomic And Dynamic Study. Skeletal Radiol. 47: 763-770. DOI: 10.1007/s00256-017-2831-2

Monday, October 24, 2022

The Big Picture

I was away on holiday with my family last week and I had some time to think. Instead of a regular post, I came up with the following questions and some answers.

My main questions were, "How can I make myself better as a physiotherapist?", "How can I ensure that all the physios in my team get better?", "How can I make our clinics better for our patients?"

My thoughts were that I always have to keep up with the research that's out there, the solid ones of course. I keep my mind open to new ways of reading the human body and what is "normal". I look out for courses to upgrade my skills. These answers were just some of ones that came to mind.

I will of course be consulting with Aized and other colleagues for their thoughts of my questions. I'm curious to hear how they would answer my many questions. That's why I value my team. We see the world through different lenses, so I learn from their views too.

A very important group of people to consult too would be our patients. I want to find out what they think about their experiences at our clinics, and act upon them wherever needed.

This journey of life, of being a physiotherapist, of running our clinics is full of ups and downs. I keep my eyes on the big picture. The big picture is that each and every person who comes to our clinics feel heard, helped, understood and hopeful. That's really at the centre of all we do.

Sunday, October 16, 2022

My Patient Was Asked To Go For Functional Training

My patient said her friend told her she should attend a 'functional training' (FT) class in order to regain her strength and mobility after she broke her ankle. 

She was also told that that FT would improve her neuromuscular adaptations (increasing the efficiency the way her body moves and safety during activities related to daily living, work and sports). Other terms include high intensity functional training (HIFT) and functional fitness (FF).

I shared with her what I read regarding a review on whether FT programs are different from traditional strength, power, flexibility and endurance training programs that are already being used in the physical training of professional, recreational athletes, healthy adults and geriatric populations.

The authors focused on the FT definitions, exercises employed and the neuromuscular adaptations reported. Firstly, they found that there is no agreement on a universal definition for FT. 

FT programs hope to improve the same neuromuscular adaptations similar to traditional strength, power and endurance training programs. The exercises employed are in fact the same. 

The main confusion with these 'new' training programs is that (other than the new fancy names) they often always overlap with traditional strength, power, endurance and flexibility programs. There is also no precise definition of functional movements. Do our muscles perform any non functional functions?

Some studies have classified that FT involves resistance training while FF has been defined as a trend using strength training. So, both FT and FF can be easily described as strength training programs.

HIFT was defined as high intensity and high volume exercises with short rest intervals. This is similar to a strength, power, and endurance session elite athletes use during specific phases of training. In fact FF has also been known as HIFT. So FF is actually HIFT. Since exercise intensity is a training variable and not an exercise type, FT and HIFT is the same training program performed at different intensities.

The authors concluded that FT has no consistent and universal definition. FT programs and exercises are not different from those already used in sports training since the neuromuscular adaptations are the same. The authors concluded that FT is not different from traditional strength, power and aerobic endurance training.

In short, there is no "non-functional" or "traditional" training. There is no real need or rationale in classifying exercise training programs as FT.

The names of these new training progams may sound cool and fancy, but you now know that they are in fact similar to weight training. 

The authors also recommended that the terms FT, HIFT and FF no longer be used to describe any training program. These can be easily classified as strength, power, endurance and flexibility programs. I found that a little too harsh since they are just names to describe training programs. At least now you know.


Ide BN, Silvatti AP, Marocolo M et al (2022). IS There Any Non-functional Training? A Conceptual Review. Frontiers Sport Active Living.3: 803366. DOI: 10.3389/fspor.2021.803366.

Sunday, October 9, 2022

Thoracic Outlet Syndrome

picture from mountainhp
We had a Team Singapore cyclist who came to our clinic complaining of arm weakness, tingling sensations, pins and needles in his biceps and forearms after full on sprints. This did not happen during the sprints, but after. He also complained of neck pain and some sensations of electric currents in his neck region when he tried looking upwards.

picture from J Manip Phy Therapeutics
The doctor he saw at the Singapore Sports Institute diagnosed him with compartment syndrome in his arms. With compartment syndrome, as physical activity ceases, all symptoms should start to ease. My patient's discomfort and symptoms only started after he stopped sprinting.

Individuals with compartment syndrome will usually complain of pain, paraesthesia (or pins and needles), their limbs (usually legs) being very tight, tense and full of pressure during training or doing the offending activity. Temporary paralysis can occur sometimes. It usually happens to athletes at the start of the season, after their break when they train too hard, too soon. 

During exertion, the muscles expand and they fill up the space in the legs and "squeeze" the nerves and blood vessels there leading to sensations of tightness, pressure or pins & needles as the connective tissue that separates each section or compartment does not stretch hence leading to the term.

My patient probably has thoracic outlet syndrome (TOS) instead of compartment syndrome. TOS occurs when blood vessels or nerves in the space between the collar bone and first rib (this space is known as the thoracic outlet) are compressed causing neck, shoulder and arm pain and numbness in the arms and fingers.

There are a few types of TOS. My patient probably has the most common version known as neurological TOS, when the brachial plexus is compressed. The brachial plexus is a big network of nerves from the spinal cord and it controls muscle movements in the shoulder, arm and hand.

A common area where TOS occurs is in the interscalene triangle (formed by the brachial plexus, the subclavian artery exiting the neck area between the anterior and medial scalene muscles and the inner surface of the first rib). 

Brachial plexus
Entrapment in the interscalene triangle may be due to brachial plexus passing through the anterior scalene (especially when the anterior scalene is larger). In my patient's case, since he is a track cyclist (with bulging neck and arm muscles) who sprints in a velodrome with excessive traction forces while sprinting plus deadlifting and snatching the Olympic bar during weight training, all these factors could very well contribute to his TOS.

After a detailed questioning and physical assessment, we managed to treat his spine and and the nerves in that region. That cyclist was able to train without the accompanying pain and symptoms after.


Dahlstrom KA, and Oliver AB (2012). Descriptive Anatomy Of The Interscalene Triangle And The Costoclavicular Space And Their Relationship To Thoracic Outlet Syndrome: A Study of 60 Cadavers. J Manip Physiol Therapeutics. 35(5): 396-4001. DOI: 10.1016/jmpt.2012.04.017

Sunday, October 2, 2022

Coffee's Performance Enhancing Powers

I remember reading about how drinking coffee can help improve sporting performance in endurance races when I was 17 and competing in track and field races back then. I was not a regular coffee drinker then (nor now). I made myself a cuppa before a track race held at the NUS track (1500m) and ran a personal best!

Back then, I read that the caffeine in coffee was a stimulant and that it enhanced fat burning to give nuscles more energy. Another theory was that caffeine acts in the brain to make  physical exertion feel easier (by blocking receptors that detect adenosine, a molecule that detects fatigue). This also helps in all out bursts of strength, prolonged endurance and cognitive effects like enhanced attention and vigilance.

Fast forward to a recent study that involved cyclists who completed time ridden to exhaustion tests at a predetermined intensity. They could sustain that intensity for around 5 minutes on 9 separate occasions. They were wired up with electrodes and other equipment before and after the rides to assess brain function, circulatory system efficiency and muscle function.

The cyclists did similar rides each time. Either 5 miligrams per kilogram body weight of caffeine was ingested an hour before the ride, or a placebo was taken. In some rides, they stopped the ride prematurely at either 50 percent or 75 percent of the time achieved in the baseline test to assess mid ride neuromuscular function.

In the final ride, the riders were given caffeine but were stopped at the exact time they had given up in the previous placebo trial to get a similar comparison of the effects of riding at a given power for a given duration with or without caffeine.

Here's a summary from the fairly complex analysis by the authors. Caffeine works! The cyclists lasted 14 percent longer (5:55 min) with caffeine compared to the placebo (5:14 min). This is equivalent to a 1 percent gain if the riders did a race or time trial.

Caffeine did help the muscles delay loss of power. Those taking the placebo at the 75 percent mark of the test had lost 40 percent of muscle power compared to less than 35 percent for those who had taken caffeine. At exhaustion those taking the placebo could generate only 60 percent less force than when they were fresh. With caffeine, the loss was 45 percent at the exact same time, pace and power.

The brain (or central nervous system) sent weaker signals to get the muscles to work when the cyclists got more tired when they ingested the placebo. With caffeine, the signals never declined, even when the cyclists reached exhaustion. Their brains were still enthusiastically getting their muscles to contract.

Caffeine also kept oxygen flowing through their arteries, as measured by a pulse oximeter attached to the cyclists' right fingers. There was only a mild decrease at exhaustion compared to a steady decline seen in those who took the placebo. The authors suggested that having more oxygen available may be one of the reasons the muscles kept working better during caffeinated rides.

This study also shows that caffeine also reduced perceived effort - just like what I read when I was 17. The pace you're holding definitely seems easier.

For those of you that are keen to try caffeine, the authors suggest 3 to 6 milligrams of caffeine per kilogram of your body weight taken an hour before your event starts. Higher doses may speed up your heart rate, not what you need during your race. Regular coffee drinkers may get a slight gain if you stop drinking coffee for a week to get that boost.


Cristina-Souza G, Santos PS, Santos-Mariano AC et al (2022). Caffeine Increases Endurance Performance Via Changes In Neural And Muscular Determinants  Of Performance Fatigability. Med Sci Sports Ex. 54(9): 1591-1603. DOI: 10.1249/MSS.0000000000002944