In my first article, I wanted to highlight to the general practitioner and the specialist dentist what a problem back pain can be. In this article I want to look at what happens if back pain is occurring while the practitioner is working and what can be done to alleviate the problem.
The sedentary athlete
Sitting for long periods of time can severely affect an athlete’s performance. The muscle imbalances that may occur are illustrated in Figures 1 and 2 and listed below:
• Tight hip flexors, hamstrings and calf muscles
• Tightness of external hip rotators
• Limitation of the lumbar spine
• Stiff thoracic spine
• Protracted and elevated scapulas with weak lower trapezius and serratus anterior
• Tight and weak posterior cuff muscles
• Poked chin posture associated with weak deep neck flexors and overactive upper trapezius, levator scapula and rhomboid muscles.
As practitioners, whose livelihood is based on being a top class performer, we become the sedentary athlete. We strive to deliver high standards of patient care and yet don’t take good care of ourselves. During a day in the surgery we need to ensure that we have mini rest breaks where we can stretch and change positions to minimise these muscles shortening and causing an imbalance (Valachi B, Valachi K, 2003).
We need to maintain a good working posture that promotes the use of only the stabilising muscles of the spine so that the larger, fast-twitch mobilising muscles are not used for posture control. These mobilising muscles soon tire and are responsible for the pain that results from muscle spasm (Pilkington RJJ, Paul JE, 2006).
So what is the correct working posture?
The correct working position is one where the spine maintains its normal curvatures (lordoses). The spine is then in its neutral zone position (Figure 3) and the practitioner can work from this stance in an ergonomic fashion (Figure 4).
Four-handed dentistry is based on this concept (Paul E, 1981). The practitioner maintains this neutral posture while working in the various quadrants of the mouth and by doing so there is a minimal amount of postural strain and loading on the spine.
There have been several papers identifying the ways in which common musculoskeletal problems can affect the various members of the dental team (Fish DR, Morris-Allen DM, 1998).
However, there still appears to be a deficiency in undergraduate teaching in this important topic, usually with the practitioner only starting to look at this aspect of practice once he or she starts to suffer from back pain. An understanding of functional anatomy will make the practitioner aware of what to look for when choosing the correct ergonomic aid to assist in maintaining the correct working posture.
The lumbopelvic region
In the lower part of the spine the lower curvature is the lumbar lordosis. This position is very easily lost as we decondition ourselves through slouching and adopt the characteristic slumped ‘C’-shaped posture. This position posteriorly tilts the pelvis and causes muscle weakness and shortening in the muscle groups (as shown in Figure 2).
Ergonomic seating that helps the practitioner to maintain the neutral position of the spine in its anatomical position is part of the solution in protecting the lower spine. Saddle seats, for example, are designed so that the lower spine is maintained in this neutral position.
The cervical and pectoral/scapular region
The health implications of poor posture are a big problem in 21st century dentistry. It has been shown that good ergonomic seating can help the practitioner protect the lower back but the upper part of the spine remains extremely vulnerable. If the practitioner fails to learn the principles of four-handed dentistry and to wear loupes then postural distortion will occur (Figures 5 and 6).
The use of loupes assists the practitioner in reducing this amount of flexion and deviation from the neutral position by increasing the declination angle. This ensures that there is less head tilt for the same amount of viewing angle. Most endodontists have already incorporated the use of loupes into their clinical practice.
From research one can see that the more the practitioner deviates or flexes away from the neutral position of the spine, the quicker the postural muscles will fatigue. Most of this early work was pioneered by Chaffin (1973).
As mentioned in the first article, the core stabilising muscles need to be isolated and exercised (Richardson CA, Hodges PW, Hides JA, 2004). This will allow those overworked, shortened muscles to release and lengthen gradually while allowing those weakened muscles to be recruited and retoned. Pilates-based conditioning exercises are excellent at addressing these muscle imbalances.
Chaffin DB (1973) Localised muscle fatigue – definition and measurement. Journal of Occupational Medicine 15(4): 346-54
Fish DR, Morris-Allen DM (1998) Musculoskeletal disorders in dentists. New York State Dental Journal 4: 44-8
Paul E (1981) Are you sitting comfortably? Dental Update Nov/Dec: 559-566
Pilkington RJJ, Paul JE (2006) The dentist and the back. Private Dentistry 11(7): 79-85
Richardson CA, Hodges PW, Hides JA (2004) Therapeutic exercises for lumbopelvic stabilization. 2nd ed, Churchill Livingstone
Valachi B, Valachi K (2003) Preventing musculoskeletal disorders in clinical dentistry. Journal of the American Dental Association 134: 1604-12
For further information:
1. Contact Dr Richard Pilkington for ‘Happy backs for dentists’ to learn about how to condition and rehabilitate your back; email: firstname.lastname@example.org
2. Contact Ellis Paul to learn about ‘Seated four-handed dentistry‘; tel: +44 (0) 20 8958 6547
3. Visit the ‘Happy backs for dentists’ website at www.richpilkington.pwp.blueyonder.co.uk/happybacks
4. Purchase Ellis Paul’s Perfect Posture for the dental team DVD from www.smile-on.com
5. Excellent conditioning programmes are the Body Control Pilates exercises. Visit the website www.bodycontrol.co.uk for further details
6. To learn physiotherapy exercises for back care and for ergonomic advice visit www.physiotherapy.co.uk