An athlete’s lower spine (lumbar spine) may usually perform demanding and extreme tasks without problems. The highly mobile lumbar spine and its associated muscles and ligaments, are an important but under recognised source of great dynamic power during most dynamic spots ie. a golf or baseball swing, a gymnast’s landing, a power-lifter’s heavy squat, or a boxer’s punch. In static mode, it functions to help maintain an infielder’s stance, a cycler’s tuck, or a ballerina’s arabesque. Not infrequently, the low back is revealed, by pain and dysfunction, to be one of the most common reasons for missed playing time by professional athletes.
The role of the lumbar spine is 2 fold:
- Dynamic power
- Static stability
Back pain appears to be more common in elite athletes than the normal population: in fact, it has been reported that 75% have had one or more episodes of back pain throughout their athletic career. This has been said to be due to the increased physical demands placed on the spines of athletes in the course of training or competition.
The increased demands placed on the spines of athletes means that the discs situated between the lumbar vertebrae are also put under increased loads and stresses. These repetitive impact stresses can produce little tears within the disc; firstly circumferential tears on the tough outer ring. With continued stress, these circumferential tears can progress to radial tears, which causes leaking of the disc fluid. At this stage, plain radiographs would show mild decreases in disc space height. This causes a diminished capacity of the disc to sustain loads, thus placing greater demands on the posterior facet joint between the two involved vertebrae. This causes degeneration of the articular surfaces. Furthermore, with time, advanced degenerative changes, such as osteophyte formation in both the disc and the facets, are an attempt at auto-stabilisation.
Disc Mechanics and Sport
Every sport places unique demands on the lumbar spine and, in turn, the intervertebral disc. Large forces are produced in the disc during various athletic manoeuvres. Here are some interesting evidence based examples:
- A golf swing, a primarily torsional activity, produces 6100 and 7500 N of compressive force across the L3-L4 disc in amateur and professional players, respectively.
- Maximal lumbar compressive forces are about 6100 N in rowers. Similarly, fast bowling (or pitching) during cricket can place large forces on the lumbar spine, which may be lessened with proper technique.
- Forces in the L4-L5 motion segment during blocking manoeuvres in five football linemen average peak compressive loads of >8600 N, with an average peak sagittal shear force of 3300 N. This suggests that football lineman are at risk for routine repetitive disc micro-trauma.
- Weight lifters reach an average lumbar compressive loads of >17,000 N. A half-squat exercise with weights approximately 1.6 times body weight produce compressive loads across the L3-L4 motion segment of about ten times body weight (approximately 7000 N for an average 70-kg person).
It has been made clear that the participation in sports appears to be a risk factor for the development of disc degeneration, with poor technique increasing the risk. Disc degeneration also appears to be influenced by the type and intensity of the sport.
Reducing the Risk of Disc Degeneration in Athletes
All athletes should be screened prior to participating in sports. Screening should involve a full body analysis including a complete muscle balance check. The athletes sport technique must also be analysed. Any findings should be addressed immediately with pre-injury rehabilitation in order to prevent risk of disc degeneration. Any flaws in sporting techniques must also be addressed. It is important for the athletes coach and sports therapist to work together with the athlete to reach goals in the prevention of injury risk throughout their sporting life.
Treatment of Disc Degeneration
If an athlete is too late for pre-injury screening and has developed degenerative disc disease specific rehabilitation for this condition has shown to be beneficial. Treatment and rehabilitation for low back pain caused by a degenerative disc may involve an initial brief period of rest with the administration of pain reducing andanti-inflammatory modalities (ice/heat, anti-inflammatory drugs, manual therapy), although personally as a therapist I always like to minimise rest periods as much as possible. Once the pain is controlled the athlete may begin an early exercise program to restore lumbar range of movement. Thereafter, the athlete must begin a more specific rehabilitation program to regain lumbo-pelvic strength, control and stability. The aim of rehabilitation should be to return the athlete to their sport pain-free, and with re-injury prevention advice and a maintenance program.
If you are experiencing back pain, whether it is related to sport or not, contact me for advice on firstname.lastname@example.org or ask questions here.
Author: Jordane Zammit Tabona, founder of Function360