It is a story told over and over again across all sports at all levels and in every age group; many athletes return to competition too soon after injury or surgery. Some head back to the DL or to the operating room with an exacerbation or recurrence. Others go on to injure another body part. The reasons are clear. Playing at less than full capacity makes it easier to place excessive demand on already challenged tissues. Often the altered mechanics that result from playing hurt also creates excessive demands on other areas.
I've written versions of this scenario many times. This two-part piece should give you a greater understanding as to why this will continue to happen until the athletes and those directing them begin to take a longer view. This will require an appreciation of the body's limitations, the healing process and the stresses of the activities involved. But mainly, it means putting less emphasis on machismo, ego, pride and proving oneself, and weighing these against the fact that more time out to rehab properly in the short run is likely to result in less time out in the long run... Maybe even a longer career, not to mention a healthier retirement. Even the bottom line may be better served. This philosophy also takes into account that, in select cases - particularly for certain injuries in the pro ranks - it may be prudent to opt for surgery immediately after injury rather than take a wait-and-see-approach (see Mark Teixeira). This is especially so if there will be pressure to return too soon. When appropriate, this choice would limit the episodes of delayed surgery following a failed rehab or setbacks after unsuccessful return to competition.
Without going too deeply into the science behind the healing process here's the bottom line:
• One week after sustaining an injury, soft tissues exhibit approximately 3 percent of pre-injury tensile strength.
• At three weeks post trauma, soft tissues have been found to function at about 30% of normal tensile strength
• At the three month mark, soft tissue healing has progressed to approximately 80% of normal tensile strength
The only interpretation is that after significantly straining a tendon, healing takes time; it cannot be rushed. An athlete back in competition who is loading the tissues at 100 percent of the normal demand -- but whose tendons exhibit significantly less than normal tensile strength -- will likely suffer breakdown due to overuse (see Kobe Bryant). Now you can see why hamstring strains and oblique injuries can be so pesky and recurrent.
Complete healing may actually take a year or more. Even then, there may be a new normal established that resembles but doesn't totally measure up to what was. How closely this new normal resembles the original depends on the area of injury, the degree of damage that occurred, the course of care and the general health of the individual. That doesn't mean waiting a full year to play after most injuries, but it invites caution, a guarded progression in rehab and a more sensible approach to returning to activity. Faster and more isn't always better.
First a quick review: ligaments connect bone to bone; stabilizing joints, helping to guide their motion and assisting with position sense. Due primarily to an insufficient blood supply, ligaments heal slowly, cannot be successfully repaired and require surgical reconstruction if ruptured. Tendons connect muscles to bones, transferring the forces that control movement. In order to function optimally, tendons must glide smoothly and be of normal length. There are often flaws evident in these tissues after injury, even once healed.
When overstretched, ligaments sprain and tendons are strained. Both types of injury actually represent a degree of tearing of the tissues that is graded on a scale from 1-3, with Grade 1 being only a mild stretch without physiologic tearing, Grade 2 being a partial tear of some degree, and Grade 3 being a complete rupture.
Then of course, there are muscles, which account for as many as half of all sports injuries. They too suffer strains/tears that are graded from 1 to 3 and can cause significant impairment. Additionally, muscle strength is inhibited in the acute stage after other soft tissue and bony injuries due to localized swelling. Muscles also suffer deconditioning from the disuse that follows injury. Weakness typically occurs in many muscles of the injured extremity, not only those most intimately connected to or surrounding the injured region. Muscle strength and endurance are restored over time. It is a process. Excessive loading on subpar strength - or for too long beyond the fatigue point of muscles - will lead to injury. It may be the weakened muscles themselves that are strained, but injury might also occur anywhere along the chain.
It is important to prevent the proliferation of scar tissue in muscle and tendon during the healing process in order to maximize the tensile strength of the healed tissue and enable tendon to glide properly. This can be accomplished by a brief period of immobilization (1-5 days) followed by therapeutic interventions, some of which gradually reload the involved tissues to restore function. These include progressive strengthening (often with an emphasis on eccentric exercise), movement, and agility programs. Interestingly, in contrast, treatment must take into consideration that prolonged immobilization will likely result in weakened tissue.
Rehab should also account for the fact that there is generally a dominant, or stronger, extremity. If the dominant side is recovering from injury, simply comparing its strength to the opposite side may not be sufficient. Competitive function may not be fully restored until strength exceeds the non-dominant side, as it did prior. Dominance often accounts for up to a 10 percent difference in strength from one extremity to the other. On the flip side, an imbalance of greater than 10 percent has been shown to put an athlete at risk of injury. This circumstance must also be managed. The value of comprehensive pre-season screening at all levels of sports to establish baseline measures is clear.
The bottom line: Athletes should not be cleared to return to sport until the injured area is no longer tender to touch, sufficient joint range of motion and normal muscle strength are achieved, and they can perform the tasks required of their position in the sport without discomfort and at full capacity - such as an all-out sprint after a hamstring strain. In addition they must no longer have any apprehension in performing these activities.
Tune in tomorrow for Part II of this article.
*Note: My thanks to Michael T. O'Donnell, PT, DPT and Stephen Reischl, PT, DPT, OCS for an excellent presentation on Musculoskeletal Tissue Healing at the APTA conference last week. I've taken the liberty of boiling down much of the information (while adding my own two cents) in the writing of this article.