Evolving Diagnosis and Theories on Ankle Impingement
Ankle pain in athletes of all kinds is a fairly common problem. When X-rays show bone spurs called osteophytes along the front part of the joint, the condition is referred to as anterior ankle impingement. Impingement is another word for "pinching".
What's getting pinched and why? Sometimes there are bone spurs called osteophytes that form along the joint line. Every time the foot and ankle move, the extra bone jams up against the joint preventing full motion. There can also be an overgrowth of joint synovium (lining with fluid to give smooth movement of the bones) called synovial hyperplasia. And in some cases, the Deltoid ligament of the ankle gets folded over and pinched between two bones.
There are several theories about why ankle impingement develops. No one knows for sure why it happens. It makes sense that athletes who use kicking motions repetitively put a force or pull (traction) on the joint capsule. The body sets up a natural response to protect that area by laying down some extra bone. Over time, this extra bit of bone forms into a ball shape. The bone mass is rarely a smooth, round ball but often has jagged edges, which is why it is referred to as a bone spur.
Any repeated action or impact force can damage the ankle joint. The soccer player comes in contact with the ball over and over. The ballet dancer or gymnast bears his or her entire body weight on pointed toes (and ankle). The end result can be ankle impingement. It is also suspected that previous ankle injuries (sprains and strains) with ligamentous damage may be part of the picture.
Depending on which side of the ankle is involved, the impingement may be labeled anteromedial (front inside ankle affected) or anterolateral (front outside ankle affected). Before MRIs were available to show the exact location and extent of the problem, this condition was just referred to as athlete's ankle.
All types of athletes have developed this problem from dancers and gymnasts to soccer players and distant runners. Triathletes, baseball players, football players, and basketball players have also been diagnosed with ankle impingement.
In this study, a group of 41 athletes with anteromedial ankle impingement were followed for at least two years after arthroscopic surgery. The patients were male and female of all ages from 13 to 57. No one had any previous ankle surgery. Anyone with arthritis was not included in the study.
The surgeon performed arthroscopic surgery with video recording of the procedure. Any scar tissue, overgrowth of synovial tissue in the joint, and bone spurs present were removed. Basically, all tissue preventing ankle dorsiflexion (motion of pulling toes and ankle toward the face) was resected (trimmed, cut, or shaved away).
As you can imagine, a dancer, gymnast, or other athlete who can't move the ankle or kick a ball without excruciating pain has a major problem. In order to document results or outcomes of the surgery, before and after measurements were taken.
The patients filled out health survey forms indicating their symptoms and level of function (daily activities as well as sports participation). After surgery, they followed a rehab program under the supervision of a physical therapist. Throughout the study, all patients reported on their satisfaction with the results of treatment.
What were the results? Good-to-excellent! There was a 93 per cent level of satisfaction among all patients. All but one athlete was back in full action by the end of 13 weeks (some as early as seven weeks). There were a few complications (temporary nerve injury, excess scar tissue formation). Some athletes needed additional ankle surgery later for other problems.
The authors conclude from the data collected in this large set of patients that arthroscopic treatment of anteromedial ankle impingement is successful. The condition is probably more common than is normally recognized.
Surgeons are advised to be suspicious of impingement in athletes complaining of medial ankle pain. With early diagnosis and arthroscopic treatment, dancers, gymnasts, and sports players can return to full participation in a relatively short amount of time.
Future studies are needed to identify specific causes of ankle impingement. Most likely, there isn't a single cause but a group of patient factors including previous injuries that contribute to this problem. It may be possible to recognize athletes at risk and prevent the need for surgery.
Christopher D. Murawski and John G. Kennedy, MD, FRCS (Orth). Anteromedial Impingement in the Ankle Joint. In The American Journal of Sports Medicine. October 2010. Vol. 38. No. 10. Pp. 2017-2024.