Hamstring injuries in football, pt 3
Before starting any training program, we must know how to assess post-injury deficits and the player’s movement. We can do hundreds of tests, but what is essential is the muscle function or movement being evaluated. We will provide several examples.
Assessment
Pain
Pain is one of the most used criteria in injury rehabilitation protocols. During each test, we must assess pain, as well as during strength and conditioning exercises. Some research has shown significant improvements after rehabilitation protocols using pain thresholds compared to pain-free rehabilitation
(Hickey et al., 2020). However, there is still a large amount of research recommending pain-free training. We must be cautious when training athletes with movement deficits or associated injuries like low back pain.
Several rehabilitation guides recommend tenderness to palpation as one of the criteria that we must control. Aspetar Hamstring Protocol recommends recording the length and width of the area of maximum pain and the distance between it and the ischial tuberosity.
In this first phase, we can record pain in daily activities such as walking, going up and down stairs, sitting and getting up, etc.
It is also essential to record pain in each test we perform.
Strength
The hamstrings, in addition to knee flexors and hip extensors, are knee stabilisers, especially during high-intensity running. As the rehabilitation progresses,
we will progress in speed, resistance, and range of motion. Isokinetic evaluation is the most precise and used method in research, but we can also use a dynamometer or manual resistance. The latter is the fastest and most effective assessment when we want to detect painful positions, although the other two forms will give us much more precise data at the end of the rehabilitation.
Image 1. Different positions to measure knee flexion strength
Hip extension – The glute bridge exercise may be used to assess hip extension ability. Although we will see how to evaluate the hip hinge pattern later, this exercise is also very useful and can help detect movement deficits. In this exercise, it is prevalent for players to exert more effort with the uninjured leg due to pain or fear after injury. If we detect this, I recommend evaluating the hip extension strength with the Prone Hip Extension Test (Image 2), placing the resistance in the popliteal region.
Image 2. Prone hip extension test (Schuermans, et al., 2017)
Image 3. Single leg Squat (Aspetar Hamstring Protocol)
Video 1. Trendelenburg Test
Image 4. Trendelenburg gait (Gandbhir, et al., 2021)
Image 5. Lateral pelvic hike during the standing knee lift test and proportion of subjects with knee injuries (Leppänen et al., 2020).
Range of Motion (ROM)
Hip flexion and knee extension ROM may be affected after a hamstring injury. I have chosen several tests based on different hip and knee positions to evaluate it. Each test can be performed actively or passively. In all tests, we must ensure no compensatory movement in the lumbopelvic area, especially at the end of the movement.
The Straight Leg Raise Test (Image 6A) is one of the most used tests to assess hip flexion ROM. With the patient lying supine, the leg is raised with the knee extended to the point where there is an onset of pelvic movement, or the patient feels a robust and tolerable stretch without pain (López-Valenciano et al., 2019).
The Knee Extension Test (Image 6B) also begins in a supine lying position, but now, the hip is flexed 90º, and the hands are held behind the knee. The maximum possible stretch is performed in this position following the same criteria as in the previous test (López-Valenciano et al., 2019). We can also evaluate knee extension ROM with the hip in maximum flexion as the Aspetar guide recommends. This test can also assess the maximum hip flexion angle prior to knee extension (Image 6 C).
Image 7. Thomas Test
Image 8. Ankle mobility tests (López-Valenciano et al., 2019)
Table 1 shows reference values that have been used to evaluate hip, knee, and ankle ROM.
Pelvic control during high-intensity actions is crucial to the prevention of hamstring injuries. This is especially important for young football players.
In addition to specific motor patterns that require correct hip function, we must also evaluate lumbar stabilisation capacity when extension, flexion, rotation, and lateral flexion forces are exerted (Adelt et al., 2021).
The hip hinge is a fundamental movement pattern for the correct and effective execution of most exercises. If not performed well, the lumbar spine will compensate for the hip’s lack of mobility and strength. The Waiters Bow (Image 9A) is a test used to detect a lack of motor control during hip flexion.
This test evaluates the ability to flex the hip (50-70º) while standing in a neutral lumbar position (Luomajoki et al., 2007).
The test result will be negative if there is lumbar flexion or inability to reach at least 50º of hip flexion.
To evaluate control capacity over lateral flexion forces, we can use tests such as the modified Trendelenburg Test or the One Leg Stance Test (Meier et al., 2021) (Image 9B). The lateral displacement of the trunk in the last test should be less than 10 cm, and the difference between the right and left sides should be lower than 2 cm (Luomajoki et al., 2007).
Control over lumbar rotation can be evaluated with the crook lying test (Luomajoki et al., 2007) (Image 9C), in which abduction and external hip rotation are performed while lying supine with the knees flexed. There should be no compensatory movement of the pelvis or hip ROM deficits.
Lumbar hyperextension can cause excessive pelvic anterior tilt, increasing the risk of injury. For example, the Rocking Forwards Test (Image 9D) has been recommended to evaluate movement deficits in patients with low back pain (Meier et al., 2021). From the quadruped position, the hips are extended, and the body leans forward. As in all other tests, the result will be positive if the lumbar area is kept in a neutral position while the movement is performed.
