Six core control tests helped Sean Fyfe pin down the cause of a young tennis player’s lower back pain
Just out of high school, at 17 years old Jacob had embarked on a full-time tennis training schedule with the aim of playing college tennis in the United States, and possibly a career beyond that. Shortly before I saw him for the first time, he had also just significantly increased his training schedule, and within a few weeks had developed bilateral lower back pain.
The pain presented as intense tightness that was worse on the right than the left. Jacob could feel the pain when he made the kind of trunk rotations he did when making ground strokes (forehand and backhand from the baseline). The worst pain came from the rightwards rotation that he made during the follow-through for his double handed backhand.
On initial assessment Jacob’s standing rotation reproduced the pain and he was limited to about half the range of movement through the spine that I would have expected. Although he didn’t feel the pain on extension, he felt very stiff and his range of movement was quite limited. His flexion and side flexion were pain free, but again limited, particularly through the thoracolumbar junction. Slump testing reproduced tightness on both sides of his upper lumbar spine.
Even before palpating, the spasm through his lower back was evident. The quadratus lumborum muscles demonstrated very tender trigger points through the upper portion of the muscle belly. Again the right was far worse then the left. Joint mobilising revealed some stiffness through the thoracolumbar junction but Jacob did not seem to be suffering from acute joint pain or chronic stiffness.
I needed to know two more things: what Jacob had been doing for his physical training programme; and how his lumbopelvic/hip stabilising system was functioning. Once I’d heard the details of his training regime, I had a fair idea about the likely answer to my second question.
Jacob’s previous programme had comprised on-court tennis training and strength work in the gym. There were two features of his strength programme that I wasn’t happy with. First, it was not a functional (tennis-specific) strengthening regime, but rather what I like to call a ‘beach weight programme’, mostly upper body weights with exercises such as bicep curls and tricep extensions, alternating muscle groups on certain days. This is great if you want to look good in a pair of tight swimming trunks, but not great if you want to be injury free and performing optimally in a sporting arena.
The other feature was that Jacob had been given no exercises that required control on one leg. His core exercises trained abdominals and lower back extensors only. So it was no surprise that, in testing, Jacob’s single leg stability turned out to be very poor, particularly on the right.
As has often been noted in SIB, it can be very difficult to test core stability. We hear the words a lot and there are countless definitions and different methods to test, but no single way is necessarily right or wrong. Realistically in a clinic setting it is often time constraints that limit how you test. Here are six quick and simple tests that I carry out if I want to gain an understanding of how a client’s lumbopelvic/hip stability is functioning.
Test 1: The plank
What does it assess?
The ability of the lower abdominals to hold the lumbar spine in neutral against body weight.
Lie prone and prop your body up on elbows and toes, with elbows placed directly under shoulders. Hold the position.
* how well the client maintains their straight spine. If the lower abdominals are weak, the athlete will raise their upper back and the lower spine will sag into extension.
* a well controlled hold of 60 seconds signifies good lower abs strength.
Test 2: Crunches on a Swiss ball
What does it assess?
The ability of the upper abdominals to control spinal extension and flexion.
Lie supine in bridge position on a Swiss ball with fingertips resting on the back of your head. Squeeze glutes and crunch up. This is not a sit-up and the spine will not flex up a long way. The back needs to move into extension during the eccentric phase (downward move) so that rectus abdominis has to work in a lengthened position.
* control of movement, cheating strategies
* amount of shaking
* 20 well controlled repetitions indicate good strength.
Test 3: Oblique rollovers
What does it assess?
The ability of the obliques to control rotation of the lumbar and thoracic spine.
Lie on your back with hips and knees both bent up to 90 degrees (lower legs are held parallel to floor), and arms flat out to the sides at about houlder height. Using the abs to control the movement, lower both knees down on one side to just above the ground and then return them back to the starting position. Both shoulders remain on the ground throughout.
Repeat to the opposite side.
* quality and range of movement
* compensatory muscle control, cheating strategies
* any lifting of either shoulder from the ground.
Well controlled obliques will allow a client to perform 10 rollovers to each side comfortably.
Test 4: Romanian dead lift
What does it assess?
The ability of the lumbar extensors to stabilise the lumbar spine in neutral.
Stand with feet hip-width apart, holding a weighted barbell (Olympic bar) with a shoulder-width overhand grip. Knees should be soft, spine in neutral. Maintaining knee position (ie, minimal knee bend), flex at the hips and lower the bar down beyond knee level, keeping it close to the body. The down- ward movement ends when you feel the hamstrings start to stretch. Return under control.
* any loss of neutral spine position throughout the exercise (heavy weight is not necessary for testing purposes, as the point is to observe lumbar control with hip flexion)
* ability of the client to squat to the limit of their hamstring length under control
* 10 well performed repetitions suggest good strength control.
Test 5: Single leg squat
What does it assess?
The ability of the lateral hip stabilisers to control the lower limb and pelvic position. Performance
Stand on one leg and squat down, ensuring the knee stays in line with the foot, and that it does not go to far forwards over the foot.
Keep pelvis facing forwards, not dropping the hip on the non-stance side; and maintain a neutral lumbar spine. Return to the start position, holding the same alignment. Assessor observes...
* shifts out of alignment
* depth and quality of squat movement
* loss of neutral spine
* 10 repetitions on each side to a knee angle of 120 degrees or lower and no loss of align- ment indicates good strength control.
Test 6: Single leg squat jumps
What does it assess?
The ability of the lateral hip stabilises to act dynamically to control lower limb and pelvic position.
Stand on one leg. Quickly drop into a single leg squat position, and immediately jump off the leg, concentrating on straightening the leg to produce a triple extension at the hip, knee and ankle. Land and absorb the shock by sinking straight into the single leg squat position, maintaining alignment, then return to standing to complete one repetition.
* loss of control at any point during the exercise
* eight repetitions performed with good tech- nique equates to good dynamic control.
When Jacob undertook the six tests, a number of factors were revealed. Lower abdominals and upper abdominals, obliques and lumbar spine extensors were all functioning well. However, he performed tests 5 and 6 poorly. The single leg squat revealed a loss of pelvic and knee position. He was also losing his lumbar spine position, but this was related to poor pelvic control rather than an inability of the lumbar spine extensors to control the spine. Jacob was unable to perform a single leg squat jump with any control at all. It is important to note that athletes can often perform a single leg squat adequately, but as soon as you increase the dynamic nature of the exercise they lose all control.
To assemble the clinical picture, then, Jacob had poor single leg stability, related to weakness of the lateral hip stabilisers. To try to gain some control over his pelvis, his quadratus lumborum muscles were overacti- vating beyond what they were physiologically capable of and in a role they are only meant to assist in. Spasm and trigger points had developed in the quadratus lumborum muscles. This increased tone had caused a restriction of the joint movement in the thoracolumbar junction and locked off Jacob’s rotation. Hence the appearance of pain with his ground strokes, which require a high degree of trunk rotation.
Why had this problem only recently started? My belief is that Jacob had had the problem for a while, but at a sub-clinical level, not yet presenting as pain. His previous training load had been much lower, and, between training, sessions the muscles would have had time to recover. With the increased training load, the muscles were required to work harder day after day, and this intensified the problem to the point where pain began.
This is a very common problem found in all sports. Many athletes can handle a part-time training load, but your body must be functioning optimally to cope with a full-time regime, because there is so much less time for recovery. Hence the classic and oft- repeated story of the runner who has trained for 10km fun runs for years without a problem, and wants to run a marathon: all of a sudden injuries arise because of the increased training burden.
Once I had developed a clear clinical picture of Jacob’s core control, management was quite simple. The first aim was to restore a normal pain free range of movement. This required rest from tennis for approximately five days, soft tissue work in the form of massage, trigger points and stretching to the quadratus lumborum and erector spinae muscles; thora- columbar junction stretching into extension over a foam roller, and rotation stretching.
Once his symptoms had settled, Jacob began to do some strengthening work for his lateral hip stabilisers, and single leg control exercises (against a background of gradually increasing on-court work). These started with single-leg squats within a range that could be controlled ( squat depth was gradually increased); and single leg squat jumps, starting at a very low intensity (height increased as performance improved).
Once Jacob had mastered these, he progressed to lateral squat jumps, jumping up and sideways. This can be done repeatedly in the same direction, or alternating jumps to left and right in turn. The exercise increases the challenge to pelvic stability.
When Jacob could perform these exercises, I was confident that he could handle a full training load without a recurrence of his symptoms. However, further improvement to his single leg function was going to enhance his on-court movement, so we continued on with a multitude of exercises using mini-hurdles to perform single leg bounding, such as maximal single leg bounding forwards and sideways, or patterns of two forwards one back, or two sideways and one back. You can be as creative as you like with the dynamic exercises as long as the client is able to maintain good control.
In summing up this case study, I want in particular to stress the importance of assessing your client’s dynamic single leg function, and, if you find weaknesses, the importance of retraining it with a progression of dynamic exercises. This is paramount in any running and jumping sport similar to tennis or basketball.