Tendonitis is a painful inflammation that occurs where a tendon attaches to a bone. It often results from a strong pull on the tendon or repetitive small force. Common sites include the rotator cuff tendons in the shoulder (such as the supraspinatus and biceps brachii tendons), the extensor tendons in the elbow (lateral epicondylitis or tennis elbow), the flexor tendons (medial epicondylitis), patellar tendon, hamstring tendons, iliotibial band, posterior tibial tendon, and the Achilles tendon at the heel. The clinical manifestations of tendonitis include local pain, tenderness, swelling, limited range of motion around the affected tendon, and weakness in the arm or leg due to pain. Achilles tendonitis, for instance, may be at risk of tearing if pain worsens with more intense activities like running or sports.
Heel pain, a common clinical presentation, is one of the main manifestations of Achilles tendonitis. It can be caused by aerobic sports activities like running. Insufficient warm-up, exercising on hard surfaces can also strain or tear the tendon. Some individuals may develop heel bone spurs (osteophytes), which is one of the causes of tendonitis. However, many do not show bone abnormalities. Regardless of the presence of bone spurs, acupuncture can be effective if applied correctly.
For patients with Achilles tendonitis or heel pain not caused by sports, common issues include a heel-first walking habit or congenital flat feet. The former type puts excessive load on the heel during walking, while the latter lacks the shock-absorbing function of the foot arch, increasing the load on the heel. This makes them susceptible to inflammation and pain in the soft tissues, including the Achilles tendon. This is especially true for overweight or obese patients. Therefore, changing walking habits to land gently on the forefoot can be crucial in curing this condition. Flat-footed patients can also use appropriate insoles to correct the foot's stress distribution or mechanical structure.
Regarding the relationship between bone spurs and heel pain, bone spurs can be both a result of prolonged heel load and a factor irritating the local soft tissues, including the Achilles tendon. However, bone spurs are not always the cause of pain. Many patients experience complete relief from heel pain after treatment, even though the local bone spurs remain unchanged, which is the best evidence of this.
The mechanism of acupuncture treatment for Achilles tendonitis or heel pain mainly involves anti-inflammatory and analgesic effects. Accurate targeting of local reflex points and deep pain points in the heel is crucial for acupuncture treatment of this condition. When palpating chronic patients and finding nodular or strand-like hardenings, the needle must reach the center of these hardenings. With repeated stimulation, these hardenings can gradually reduce, soften, and eventually, the tenderness disappears.
Since the skin on the sole, especially the heel, is thick and sensitive, special needling techniques are required when acupuncture is applied to the sole to reduce pain and make the treatment more acceptable to the patient.