The strongest and thickest tendon in the body, the Achilles tendon can withstand a load stress of almost four times an individual's body weight when he is walking. The load stress nearly doubles when the individual is running.
The Achilles tendon is the distal attachment of the gastrocnemius and soleus muscles to the calcaneus. Injuries to this tendon are on the rise in the United States as the population ages and more people remain active later in life.
"The Achilles often gets irritated from overuse or degeneration," shared Daniel Seidler, PT, MS, executive director, Westchester Square Physical Therapy PC (WSPT) in the Bronx, NY. "Experts used to think Achilles pain was an inflammatory issue."
The most common Achilles injuries are Achilles tendinosis and Achilles tendon rupture. Tendinosis, generally the result of overuse, manifests as soreness or stiffness of the Achilles. Partial and full Achilles tendon ruptures occur most often when individuals engage in sports requiring sudden eccentric stretching, such as sprinting.
The most common acute Achilles injuries are tendonitis or bursitis. "If a patient has acute tendonitis, then the injury needs to be managed with rest from activity, ice, some external support like a heel lift or CAM walker that would decrease tendon pain, and PT modalities once the pain is under control," said Carl Gargiulo, PT, DPT, OCS, owner of Strulowitz and Gargiulo Physical Therapy in Bayonne and Jersey City, NJ, and assistant adjunct professor at Columbia University.
Acute Achilles tendonitis can typically be traced to a specific event that caused a strain or tearing of the Achilles tendon. When tendon fibers tear, they become inflamed and swollen, causing pain and tenderness in the area that can also result in difficulty flexing the foot during regular movements such as walking and jumping. Once pain is under control, the patient is progressed to stretching and strengthening exercises as he can handle it.
Retro-calcaneal bursitis, also called Achilles bursitis, occurs when the bursa becomes inflamed. The bursa-found between the back of the heel bone and the Achilles tendon-protects the smooth tendon from the rough bone. When pressure is placed on this tendon, the bursa becomes inflamed.
Achilles bursitis can be managed with ice and rest. Sometimes shoe modification is necessary to ensure that the back of the shoe is not rubbing against the bursitis. "Once the bursitis subsides, the Achilles does not need as much strengthening as with tendonitis," said Dr. Gargiulo.
Chronic and Acute Ailments
With tendinosis, the patient has microtears in the tissue in and around the tendon. "Chronic tendinosis is a big group of problems because it is tendonitis that has recalcitrated and become debilitating," explained Dr. Gargiulo. "It's a degenerative process."
According to Dr. Gargiulo, the treatment of chronic tendinosis has seen the biggest changes and gains in the PT field during the past few years. "We are fortunate to have excellent resources and exercises to help treat these patients," he observed. "The resources are excellent because they work."
The rehab that PTs do at Strulowitz and Gargiulo Physical Therapy is loosely based on a study conducted by Dr. Hakan Alfredson et al. in 1998 in Sweden. "It was a landmark case at the time," Dr. Gargiulo said. "The intervention involves a heavy load of eccentric calf and Achilles tendon exercises."
The investigators studied the effects of eccentric exercises in patients with chronic tendinosis. According to Dr. Gargiulo, the investigators found excellent results from specific training but not from conventional interventions such as pain medications, change of shoes and normal physical therapy.
Carl Gargiulo, PT, DPT, OCS, owner of Strulowitz and Gargiulo Physical Therapy in Bayonne and Jersey City, NJ, teaches a patient with chronic tendinosis how to do eccentric exercises.
According to the study, heavy load eccentric exercises provide both short- and long-term relief for patients. "We unload the tendon by doing three sets of 15 reps of eccentric training," Dr. Gargiulo explained. "We have the patient stand on both legs, then lift the right leg (unaffected leg) and perform a one-legged calf lift on the left side (injured leg). We ask the patient to repeat the exercise a couple of times a day."
Many therapists support eccentric exercises for the treatment of chronic Achilles tendinopathy. Patients are to be instructed on the proper mechanics of eccentric exercises. Once pain has been reduced, patients may complete the exercises while wearing a backpack to make it more difficult.
"My clinic follows this protocol of eccentric exercises," said Dr. Gargiulo. "The exercises get results because they work the muscles harder and may have implications on blood flow in the area. It is superior to other types of treatment." Those with eccentric training are better prepared to go back to running in an earlier timeframe.
Modalities used may include phonophoresis or iontophoresis. The clinic uses ultrasound less often because evidence is more sparse than with the other study. Not as much evidence to support the use of most modalities. "Both acute and chronic stages can be treated with iontophoresis and friction massage," said Dr. Gargiulo. "Those that have a physiological basis can be used."
The PTs at WSPT initially follow the RICE (rest, ice, compression and elevation) principle for Achilles injuries. WSPT's approach is to immobilize the area in the short term in a boot or brace. "This approach prevents further degeneration and does not put too much stress on the area in the short term," said Seidler. Depending on the severity of the injury, the PTs generally recommend one to four weeks of immobilization or lack of stress on the tendon.
Patients in the acute phase are often referred to WSPT with a brace or a heel lift and Seidler's job is to gradually wean them off the device. "They want to get off the assistive devices," he said. "When possible, I like patients to exercise without external support. But I encourage them to use their braces and orthotics as prescribed."
According to Seidler, the real work comes later. Once the area has been properly rested, then the progressive rehabilitation begins, whether the injury is chronic or subacute.
"Eccentric exercises tend to be most effective," said Seidler. "There's an ongoing debate about whether to call the approach eccentric strengthening. It's actually a combination of stretching and strengthening and serves to strengthen the tendon without irritating it."
The PTs at WSPT do a lot of proprioceptive strengthening as well. "We start with static balance and progress to dynamic balance," Seidler shared. "We may initially do static balance by standing on one leg to balance before progressing to more dynamic balances. We may use a body blade in one hand to cause muscles of the lower opposite leg (injured leg) to balance and to trigger neuromuscular re-education. This technique fires the neuromuscular pathways without putting too much strain on the tendon."
Achilles tendinopathy is an overuse injury, often the result of running too hard or even walking for some people. "It's too much activity to the point of degeneration or shredding of the tendon," Seidler said. "We tell those patients to take their activity level down a bit. We may begin with standing on the affected leg and adding more dynamic stabilization and movement as they can tolerate."
From the beginning of therapy, the PTs at WSPT recommend a home program for those who can tolerate the additional exercise. "I tell patients to strengthen to the point where there's no pain and they are seeing gradual progression without irritation," said Seidler.
WSPT sees mainly athletic injuries or those from the workplace such as a delivery driver who spends a lot of time on his feet, driving and getting in and out of truck. "We often use aquatic therapy for Achilles injuries," Seidler said. "We can simply do more aggressive exercises than we can on land."Aquatic exercises include eccentric heel raises and fast walking on a treadmill, progressing to running. "After a patient masters walking in the pool, she will transition to a treadmill on land and then walking on land without a treadmill."
Seidler also likes using low-level laser as an intervention for Achilles. "The evidence is not as strong for lasers, but we have great results with most Achilles tendonitis and tendinopathy," he relayed. "I typically use low-level laser at the end of a session."
Seidler may also use therapeutic tape to decrease pain in the acute phase. He finds the tape particularly useful if the patient needs to manage pain during an event or race.
Extrinsic and Intrinsic Factors
Intrinsic risk factors generally include biomechanical issues and anatomical predispositions. A high arched foot, for example, may predispose a patient to limited range of motion that stresses the tendon.
According to Dr. Gargiulo, orthotics can be helpful to control some of the intrinsic factor such as shock absorption and control or to lessen the effects of limited motion. "Off-the-shelf products may work for certain types of feet or custom-made orthotics may be necessary for others," he shared.
Ill-fitting shoes can also result in Achilles problems, according to Dr. Gargiulo. "Wearing heels excessively can shorten the tendon and transitioning into regular shoes stresses the tendon," he told ADVANCE. The main extrinsic risk factor is excessive training. "Too much running is generally the culprit as well as too much running on sloped surfaces," explained Dr. Gargiulo. "Running uphill can add to the stress of the tendon."
Dr. Gargiulo noted the recent interest in barefoot running and forefoot striking and absorbing shock through the calf. "I'm interested in seeing where this trend goes," he observed. "Will barefoot running increase stress and strain on the area by toe striking and absorbing the force in the calf area? There's still a lot of research to gather to see the implications on tendonitis and tendinosis."
Rebecca Mayer is senior regional editor of ADVANCE and can be reached at firstname.lastname@example.org