The technological advances of the past twenty or so years have been extraordinary: CDs, the iPod, and plasma TVs are just a few of the devices many of us now take for granted. Some, such as cell phones, are now regarded as necessities; we wonder how in the world we ever lived without them!
Probably first and foremost among the “can’t-live-without-it” developments is the personal computer. Just a few years ago, only a handful of my friends had e-mail addresses; now, I hardly know anyone without one. Computers have certainly become indispensable for the business world and to individuals as well. They have also been great for physical therapy practices, and not only in the sense of helping run the business.
As I have noted in earlier columns, faulty posture very often leads to the development of musculoskeletal injuries. Sustained, improper positioning can cause shortening of some muscle groups while at the same time causing overstretching of others. This in turn may produce improper movements which, if repeated hundreds or thousands of times, will cause a breakdown somewhere in a muscle, tendon, or joint.
Almost nowhere do we find such a circumstance more than with long-term computer use. The areas most often affected by improper sitting posture in front of a computer are the neck, shoulders, and hands, but not exclusively. There have been a few cases where there seems to be a clear connection between extended computer use and muscle imbalances that are the apparent cause of an injury. Here’s an example:
A 50+ year-old male”mouse potato” – who also happens to be a 50 mile/week runner –presents with pain in the front of both knees. Onset was gradual over a three-month period and not due to any known trauma. Examination quickly confirms suspicion of patellofemoral pain syndrome (aka, “runner’s knee”), but without a clear precipitating factor such as increased mileage, change in terrain, or different footwear, the underlying cause is not apparent without a full evaluation of posture and muscle balance.
Further exam reveals this patient to have significant shortening of the hip flexor muscles, particularly the rectus femoris, which is one of the four muscles comprising the quadriceps. Tightness of this muscle will theoretically increase compressive forces to the back of the kneecap (patella) and/or may cause the patella to track improperly in the femoral groove, causing increased friction that affects the protective joint cartilage layer.
So now we know what the problem is and the direct cause, but we don’t really know what caused the shortening of the muscle in the first place. Further questioning focused on activities, both work and recreational,that may have changed in the month or two before this problem started. Eventually, it was discovered that this runner had started a program that required long hours on his laptop computer. Further questioning revealed his sitting position while working on the computer to be the key factor in the development of his postural fault.
This runner’s description of his sitting posture painted a picture of a low couch and high worktable, which required his using the hip flexors to pull his trunk far-enough forward to reach the keyboard comfortably. Overtime, these muscles tightened and shortened, leading to the scenario described above. Some simple stretching exercises to restore normal muscle length, in addition to the critical step of making changes in his sitting position, alleviated the problem within two weeks.
People who have to sit long hours at the computer should try to use a comfortable, but straight-backed chair that allows you to relax against the back rest without it leaning back. You shouldn’t try to “sit up straight” on your own – use the backrest for support. Additionally, you should be close enough to the keyboard to allow you arms to be relaxed at your sides, not reaching forward.
The truth is that even if it were possible to achieve an absolutely perfect sitting posture, staying in anyone position for too long is likely to create an imbalance or stress on a body part. You would do best to keep that in mind and be sure to get up and move around at least twice an hour.