Achilles insertional calcific tendinosis can cause posterior heel pain in both active and sedentary patients, and can be aggravated by activity or footwear. Accordingly, this author reviews keys to diagnosis, offers insights on conservative and surgical treatment, and provides two illuminating case studies.

Posterior heel pain is a common cause of pain and disability affecting individuals ranging from the high level athlete to the obese and sedentary. In each patient population afflicted with this condition, there are different challenges related to the treatment and the expectations of the individual.

There are a number of different clinical entities responsible for posterior heel pain including Achilles insertional calcific tendinosis. This disorder is characterized by the presence of a calcified mass in the distal Achilles tendon at its insertion site onto the posterior calcaneus. Localized erythema and edema may be present along with an inflamed retrocalcaneal bursal sac. Individuals with this disorder complain of stiffness in the Achilles tendon following a period of inactivity or first thing in the morning when they are first ambulating. Activities such as running or jumping will aggravate the condition and often force the participant to stop.

Certain types of footwear will also be problematic. Dress shoes with a stiff heel counter can rub on the area, causing irritation and blister formation. Other types of footwear for sports such as ice hockey skates or ski boots may cause significant problems due to the tight and stiff heel counter. However, patients can often modify these to accommodate the protuberance.1

Stress placed on the Achilles tendon during loading results in the initial microscopic intratendinous changes that produce microtearing of the tendons, leading to localized collagen degeneration with subsequent mucinoid degeneration or fibrosis.2 The paratenon can be involved in the process and become chronically inflamed, thickened and fibrotic.3 Over time, differentiation of tendons can result in the development of a calcified mass within the substance of the Achilles tendon. In other cases, it would appear that a posterior calcaneal spur has separated or fractured from the calcaneus.

Evaluating the Achilles tendon, researchers conducted a study to ascertain whether tendon samples harvested from patients with calcific insertional Achilles tendinopathy showed features of a failed healing response.4 The study also determined whether these tenocytes had produced abnormal quantities of type II collagen in that area. The study authors harvested tendon samples from eight otherwise healthy male individuals (average age 47.5 ± 8.4 years, ranging from 38 to 60) who underwent surgery for calcific insertional Achilles tendinopathy and from nine male patients who died of cardiovascular events (mean age 63.1 ± 10.9 years) while in the hospital. The researchers obtained histochemical, immunohistochemical and immunocytochemical evaluation of the tendons.

The results of the study demonstrated that the tenocytes from tendons of patients with calcific insertional Achilles tendinopathy exhibited chondral metaplasia and produced abnormally high quantities of collagen type II and III.4 The authors concluded that the altered production of collagen may be one reason for the histopathological alterations described in the study. Areas of calcific insertional Achilles tendinopathy have been subject to abnormal loads. These tendons may be less resistant to tensile forces. Further studies should investigate why some tendons undergo these changes.

Examination of the patient may reveal an ankle equinus, which may also be a predisposing factor in the development of the condition. One would identify a solid mass or bump in the posterior heel. Pain is typically present with side to side compression of the mass.

Palpation in the retrocalcaneal region may also reproduce pain due to an inflamed bursal sac. When one palpates the mass and puts the foot through dorsiflexion and plantarflexion, the mass will move and this indicates that it resides within the Achilles tendon. Plain film radiographs will reveal a large single calcification or multiple smaller calcifications posterior to the calcaneus in the area of the Achilles tendon attachment. A solid spur may arise from the calcaneus.

Magnetic resonance imaging (MRI) will reveal tendinosis with calcification within the tendon. Longitudinal tearing or separation of the tendon about calcification will also occur in chronic cases.

Pertinent Insights On Conservative Treatment

Initial conservative treatment of the condition consists of rest to decrease motion and irritation of the tendon. Avoiding impact or jumping activities is very important. For some patients, it may be beneficial to wear a removable walking cast while allowing gentle, non-weightbearing ankle joint dorsiflexion and plantarflexion to keep the tendon mobile in the initial phase of treatment.

Injection therapy with a local anesthetic can reduce the pain. If one makes the injection between the paratenon and Achilles tendon, it will open up inflammatory adhesions. Further treatment will include physiotherapy, oral and topical nonsteroidal anti-inflammatory medication, heel lifts in shoes and footwear modifications.

Eccentric exercises of the gastroc-soleus complex, although beneficial for mid-portion Achilles tendinopathy, are usually not as effective for insertional tendinopathy but may decrease pain in some patients.5 High energy extracorporeal shockwave therapy may also provide relief for this condition.

Emerging Insights On Surgical Repair

If patients fail to improve following six months of non-operative care, one should consider surgical management. Depending on the condition of the Achilles tendon, one may consider excision of the calcification or repair of the Achilles tendon with flexor tendon transfer for augmentation. In some cases, a calcaneal osteotomy may also be necessary to remove an osseous bump on the calcaneus.

Johnson and colleagues evaluated the outcome of a central tendon splitting approach in the surgical management of 22 patients with insertional calcific Achilles tendinosis.6 Follow-up averaged 34 months and surgeons routinely used suture anchors to augment the tendon insertion following debridement. The investigators used the American Orthopaedic Foot and Ankle Society (AOFAS) ankle/hindfoot score and evaluated shoe wear comfort and return to work.

The authors found that pain significantly improved from 7 points preoperatively to 33 points postoperatively.6 Function improved significantly from 36 points to 46 points and the ankle-hindfoot score improved from 53 points to 89 points. Patient age older or younger than 50 did not affect the outcome. The researchers concluded that a central tendon splitting approach yielded good relief of pain with improved function, shoe wear and the ability to work without painful postoperative scars.

European researchers also evaluated the surgical management of active patients with recalcitrant calcific insertional Achilles tendinopathy.7 Twenty-one patients (six women) (21 feet) (average age 46.9 ± 6.4 years) underwent surgical treatment with removal of the calcific deposit. Bone anchors facilitated the reinsertion of the Achilles tendon.

At an average follow-up of 48.4 months, one patient necessitated a further operation.7 Eleven patients reported an excellent result and five had a good result. The remaining five patients could not return to their normal levels of sporting activity and kept fit by alternative means. The results of the VISA-A questionnaire markedly improved in all patients from a preoperative average of 62.4 percent to 88.1 percent postoperatively.

The researchers recommended detachment of the Achilles tendon to excise the calcific deposit fully and reinsertion of the Achilles tendon in the calcaneus with suture anchors.7 No patient experienced a traumatic detachment of the reattached tendon.

Can Early Weightbearing Facilitate Improved Outcomes?

There has been some debate on postoperative rehabilitation.

In a recent prospective study, McWilliam reported on early weightbearing following surgery for insertional Achilles tendinosis.8 The study involved 26 patients with calcific insertional Achilles tendinosis who failed conservative treatment. When the conservative treatment failed, surgeons performed a full Achilles detachment and debridement as well as a calcaneal osteotomy.

At two weeks post-op, surgeons removed the sutures and replaced the cast with a removable version.8 The patients also used bands for resistance and began passive strengthening exercises. Depending on their comfort level, patients discarded their casts at six to eight weeks postoperatively. In the next two weeks, they began a physical therapy regimen that included proprioception, range of motion and strengthening exercises.

McWilliam found that patients’ AOFAS ankle/hindfoot scores increased from 69 points preoperatively to 87 points postoperatively after patients underwent an Achilles detachment and repair with an immediate weightbearing regimen.8 During an average two-year follow-up, he also reported that 92 percent of the patients reported good or excellent results with the procedure. The same percentage of the study cohort also said they reached their desired activity level. In addition, all but one patient in the group reported that they would undergo the operation again and only 8 percent of the cohort judged their surgical outcome as fair.

Case Study One: When An Active Senior Has Posterior Heel Pain

A very active 70-year-old female received a referral to the office with a complaint of posterior heel pain. Despite the fact that the heel spur had been present for a number of years, she said it only started to cause her some problems in the past year.

She complained of pain and stiffness in the posterior aspect of the heel and ankle that would last for a little over half an hour after sitting. If she was on her feet for an extended period of time, the area would also become very sore. Footwear had become a real problem and she found herself having to wear open heel sandals as all other shoes would rub and irritate the area.

She tried a number of non-operative modalities including physiotherapy, heel lifts and topical diclofenac gel 8%. She tried modifying her shoes and hiking boots, but this did little to alleviate her pain.

The patient is 5 feet 3 inches, weighs 127 pounds and is a non-smoker. She keeps very active, hiking in the Canadian Rocky Mountains with her seniors hiking group.

The orthopedic examination was unremarkable with the exception of the posterior heel, which had an enlarged heel spur with localized erythema and pain on palpation of the area.

Radiographs demonstrate a large posterior calcaneal spur. An ultrasound demonstrated findings compatible with chronic tendinopathy involving the distal Achilles tendon with a moderate amount of inflammation in the retrocalcaneal bursa.

With the patient under general anesthesia in the prone position with a thigh tourniquet inflated to 300 mmHg, I carried out a midline incision through the posterior Achilles tendon. I incised the paratenon and separated it medially and laterally. I made a longitudinal midline incision through the Achilles tendon down to its attachment on the posterior calcaneus.

Extending the incision medially and laterally, I raised the distal Achilles tendon attachment off the calcaneus to expose the calcification. I left the medial and lateral attachments intact. I subsequently excised the hypertrophic Achilles tendon and the inflamed bursa became visible in the proximal margin of the surgical site.

Using a sagittal saw and bone rongeur, I removed the calcification and then excised the inflamed bursa sac. I placed two Mitek GII anchors (DePuy) in the posterior calcaneus at the level of the attachment site of the Achilles tendon. Then I placed bone wax on the exposed bone and secured the tendon to the calcaneus with the suture. Further repair of the tendon occurred using a 2-0 vicryl.

I closed the paratenon with 3-0 vicryl. Skin closure occurred using 4-0 nylon with a horizontal mattress suture. I dressed the wound in the normal fashion and applied a posterior plaster slab.

The patient was non-weightbearing for two weeks. At the first postoperative visit, I removed the slab and sutures, and placed the patient in a removable walking boot with a 1-inch heel raise.

At this point, the patient was allowed to ambulate. She received instructions to remove the boot and perform range of motion exercises twice daily, pursuing plantarflexion against resistance with surgical tubing. The exercises start with the foot at 90 degrees to the leg and then the patient plantarflexes against resistance.

Every two weeks, the patient would return for assessment and I lowered the heel raise by ¼ inch. At 10 weeks, physiotherapy started. I removed the boot at 12 weeks. She returned at three months postoperatively. She demonstrated good strength and could do single limb balance with mild discomfort if she walked for longer than two hours. This did not stop her and she was back hiking with her group.

Case Study Two: When A Sedentary Patient Presents With Longstanding Heel Pain

A 47-year-old female teacher received a referral to the office with a six-year history of posterior heel pain. She says the pain had been intermittent in nature for a few years and she regularly wears open heel sandals so she has been able to manage the problem. She is obese and admits to being very inactive.

On her physician’s recommendation, she started to exercise to lose weight as she had developed hypertension and has a strong family history of diabetes mellitus. For exercise, she started walking, using an elliptical trainer and swimming.

Stiffness and pain have developed in the posterior heel. She has noticed that the bump has become larger and is at times quite red in appearance. Even when she wears her open heel sandals, the patient says the foot is painful. On a friend’s advice, she tried laser therapy, which did not relieve the pain.

She saw her family physician, who recommended a walking boot for four weeks. The pain subsided while the foot was in the boot but once the patient took off the boot and resumed her exercise program, the pain returned.

The patient is 5 feet 5 inches, weighs 272 pounds and is a non-smoker. She has a history of hypertension, sleep apnea and gastroesophageal reflux disease (GERD).

The orthopedic examination revealed limited ankle joint dorsiflexion with the knee flexed and extended. The subtalar joint range of motion was also limited and she had a semi-rigid forefoot valgus. The posterior aspect of the heel had an enlargement at the insertion site of the Achilles tendon with localized erythema and significant pain upon palpation of the region. Forced dorsiflexion of the foot also reproduced the pain. Radiographs demonstrate a large posterior calcaneal spur.

A discussion regarding the surgical management of the condition centered on the potential for a long recovery, which is common in obese and sedentary individuals with this condition. I suggested she continue the weight loss program prior to surgery but the patient stated that the pain was limiting her ability to exercise. She was very depressed as she was starting to feel better since exercising.

With the patient under spinal anesthesia in the prone position and a thigh tourniquet inflated to 350 mmHg, I carried out a midline incision over the posterior Achilles tendon. I incised the paratenon and separated it medially and laterally. I extended the longitudinal midline incision through the Achilles tendon down to its attachment on the posterior calcaneus.

Directing the incision medially and laterally, I subsequently raised the distal Achilles tendon attachment off the calcaneus to expose the calcification. I left the medial and lateral attachments intact. Minimal thickening of the Achilles tendon was present.

I removed the calcification with a sagittal saw and bone rongeur, placed bone wax on the exposed bone and secured the tendon to the calcaneus utilizing the Achilles SutureBridge (Arthrex). I utilized 2-0 vicryl for further repair of the tendon and closed the paratenon with 3-0 vicryl. Skin closure occurred with 4-0 nylon and a horizontal mattress suture. I dressed the wound in the normal fashion and applied a posterior plaster slab.

Postoperatively, the patient took anticoagulation medication and was non-weightbearing for two weeks. At the first postoperative visit, I removed the slab and sutures, and placed the patient in a removable walking boot with a 1-inch heel raise.

At this point, the patient ceased taking the anticoagulation medication and was allowed to ambulate. She received instructions to remove the boot and perform range of motion exercises twice daily and plantarflexion against resistance with surgical tubing. The exercises start with the foot at 90 degrees to the leg and then plantarflexing against resistance.

Every two weeks, she would return for assessment and have the heel raise lowered by ¼ inch. At 10 weeks, physiotherapy began and at 12 weeks, I removed the boot. She returned at three months postoperatively and demonstrated improved strength. She could not perform single limb balance and still demonstrated an antalgic gait.

At six months, she resumed her exercise and weight loss program. She stated there was some pain with walking but she could tolerate it. She returned at 12 months having lost 30 pounds and stated that the heel was almost completely free of any discomfort.

Dr. Haverstock is the Division Chief and Assistant Clinical Professor of Surgery in the Division of Podiatric Surgery within the Department of Surgery with the University of Calgary Faculty of Medicine in Calgary, Alberta. He is a Fellow of the American Society of Podiatric Dermatology.

For further reading, see “Current Concepts In Retrocalcaneal Heel Spur Surgery” in the November 2009 issue of Podiatry Today or “Keys To Diagnosing And Treating Achilles Insertional Pain And Retrocalcaneal Exostosis Pain” in the September 2010 issue.

References:

1. Williams JGP. Achilles tendon lesions in sport. Sports Med 1986; 16(3):114–135. 2. Puddu G, Ippolito I, Postacchini F. A classification of Achilles tendon disease. Am J Sports Med 1976; 4(4):145-150. 3. Fahlstrom M, Jonsson P, Lorentzon R, Alfredson H. Chronic Achilles pain treated with eccentric calf muscle training. Knee Sports Surg Traumatol Arthrosc 2003; 11(5):327-333. 4. Maffulli N, Reaper J, Ewen SW, Waterston SW, Barrass V. Chondral metaplasia in calcific insertional tendinopathy of the Achilles tendon. Clin J Sport Med. 2006; 16(4):329-334. 5. Furia JP. High energy extracorporeal shock wave therapy as a treatment for insertional Achilles tendinopathy. Am J Sports Med 2006; 34(5):733-740. 6. Johnson KW, Zalavras C, Thordarson DB. Surgical management of insertional calcific achilles tendinosis with a central tendon splitting approach. Foot Ankle Int 2006; 27(4):245-250. 7. Maffulli N, Testa V, Capasso G, Sullo A. Calcific insertional Achilles tendinopathy reattachment with bone anchors. Am J Sports Med 2004; 32(1):174-182. 8. McWilliam JR. Immediate weight bearing after complete Achilles detachment and repair for calcific insertional Achilles tendinosis. Presented at the American Orthopaedic Foot and Ankle Society 22nd Annual Summer Meeting. July 14-16, 2010, La Jolla, Calif.