Diagnosis is made by history and physical examination. Patients will report hearing a pop or feeling a snap in the posterior leg, followed by acute pain and difficulty walking. They will not be able to rise on their toes. There will be a palpable gap within the tendon itself, most typically in that watershed region 2 to 6 cm proximal to the calcaneal insertion. The Thompson test will be abnormal, demonstrating no ankle plantar flexion with the patient prone.

Open repair of the Achilles may facilitate an earlier return to normal activities and return to work than nonoperative treatment. Many surgeons feel that an accurate repair of the tendon gives the patient the best chance at restoration of functional strength, with to a faster return to sports, and a potentially lower incidence of re-rupture in younger patients and explosive sporting activities. In patients with histories significant for diabetes, morbid obesity, renal failure, chronic corticosteroid use, or chronic peripheral edema, nonoperative treatment should be considered. Vascular insufficiency is considered a relative contraindication to operative treatment. Recently, nonoperative functional treatment has shown increasing success, however, with re-rupture rates approaching the low rates seen in surgically treated ruptures without the surgical complications of tendon adhesion, wound dehiscence, and infection. Functional treatment is therefore an option in a compliant patient not participating in elite-level sport. Ultimately, the decision for the form of treatment is made by the surgeon and patient.

The goal of the procedure is to restore the integrity of the tendon at the appropriate length to allow for rehabilitation. Theoretically, delaying surgery by approximately 1 week after rupture allows for the consolidation of tendon ends and decreased soft-tissue swelling, making the repair technically easier. Straight posterior or posteromedial approaches are the two most commonly used incisions. Supine positioning with a large contralateral bump through the posteromedial approach offers a decreased chance of skin problems and easy access should FHL transfer be needed unexpectedly. Some surgeons prefer the prone position.

The surgical incision is made just posteromedial over the medial tendon. This approach also prevents injury to the sural nerve. To minimize wound complications, careful soft-tissue techniques must be performed, taking care not to traumatize skin edges or make any flaps. The dissection should be performed sharply directly down to the paratenon. To minimize subsequent adhesions between the tendon repair and the skin, the paratenon should be opened with care to allow its closure after the repair. The tendon repair should be made with the ankle in neutral position, not in maximum plantar flexion. If the repair cannot be achieved in neutral position, an FHL transfer may be used to bridge any gap. A strong, braided, nonabsorbable suture is used in performing the repair, typically following a Bunnell or Krachow-Hungerford pattern. Alternately, or additionally, a suture anchor may be employed to further secure the repair, and is inserted into the calcaneus. Care should be taken to bury knots under or within the tendon whenever possible, as prominent suture knots are irritating to the patient and can lead to complications in skin healing. Meticulous wound closure in layers is performed to include the paratenon, followed by a bulky compressive dressing and plaster splint application, with the ankle placed in a neutral position. This splint remains on for 10 to 12 days postoperatively.

Complications of Achilles repair can include sural nerve injury, infection, wound healing problems, and scar sensitivity.

This technique is used for acute-on-chronic ruptures or chronic Achilles tendinopathy unresponsive to nonoperative treatment. Acute-on-chronic ruptures should be suspected in patients who report a previous history of calf tightness, Achilles tendonitis, plantar fasciitis or history of playing sports with ankle sprains and Achilles strains, with concomitant equinus contracture on physical examination. A gastrocnemius contracture plays a definitive role in Achilles pathology, and isolated tightness of the gastrocnemius can place excess tension on the Achilles, leading to Achilles and plantar fascia disorders. Be sure to examine the patient’s contralateral leg for equinus contracture (Silfverskiöld test), and to evaluate lateral radiographs for evidence of calcifications within the Achilles tendon or posterosuperior calcaneal spurs, all suggestive of a more longstanding tendinopathy. In the presence of such findings, especially in older patients or sports participants, surgical repair should include primary repair of the Achilles, with débridement of any diseased tissue, and augmentation with a FHL transfer.

Delayed diagnosis or missed injury may also result in the need for reconstruction with tendon transfer because of tendon retraction and a gap present on attempted direct repair.

The surgery is similar to a direct repair. In addition to the medial incision made for the Achilles repair, a second incision is performed along the medial aspect of the foot (the medial utility incision), in order to retrieve the FHL tendon more distally, with sufficient length for the transfer. The muscle belly of the FHL runs more distally in the leg, right to the back of the ankle joint. Transferring the FHL into the Achilles brings this vascular muscle belly into the relatively avascular, diseased Achilles tendon. In addition to bringing vascularity, a transfer of the FHL makes a stronger repair (more tissue) and potentially more strength to the patient (additional muscle to plantarflex the ankle). Layered closure and plaster splint application is identical to that performed in primary repairs.

The downside to performing the FHL transfer is the need for a second incision, resulting in occasional mild complaints related to a decrease in push-off strength in the hallux. It is possible to harvest the FHL for transfer without a second incision, although the tendon will be shorter and the repair to the calcaneus may be weaker.

Potential complications are the same as those in a primary rupture repair.

Chronic insertional Achilles tendinosis is treated with débridement of degenerative tissue with partial calcanectomy and proximal calf lengthening.

In insertional Achilles tendinosis, patients develop focal tenderness and prominence of the distal tendon above or over the posterior tuber. Lateral radiographs may show ossification/calcification of the Achilles insertion on the calcaneus or a Haglund’s deformity (a bony prominence of the calcaneal tuberosity). When nonoperative measures fail to relieve the discomfort, surgical treatment should be sought. If a gastrocnemius contracture is identified in a patient undergoing surgical treatment of Achilles tendinopathy, simultaneous gastrocnemius lengthening should be performed.

The mainstay of surgical treatment involves débridement of the diseased tendon. The patient is placed in the prone position. Two incisions are used. The proximal incision is at the gastrocnemius musculotendinous interface to perform a Strayer procedure or gastrocnemius recession. It is placed medial to the midline to decrease the possibility of sural nerve injury. The subcutaneous tissues can be retracted, which allows direct visualization of the gastrocnemius tendon. The space between the gastrocnemius tendon and the soleus tendon can be opened; the gastrocnemius tendon is released and allowed to retract. The distal incision is a midline incision over the tuber and distal Achilles tendon. The incision is carried straight down through the paratenon and periosteum without raising flaps. The tendon can then be dissected subperiosteally
medially and laterally, taking care to not completely detach it from the tuber. If present, a Haglund’s deformity is resected, along with any inflammatory tissue between the calcaneus and the Achilles tendon just above the insertion (retrocalcaneal bursitis). A suture anchor inserted into the tuber, tangential to the line of pull, can secure the Achilles to the tuber, yielding a more secure repair of the tendon. Closure and immobilization mirrors that of the previously described repairs.

While postoperative rehabilitation is best tailored to the individual patient, there are general guidelines for rehabilitating an Achilles repair. The initial postoperative stages involve only the patients themselves, and as healing progresses, formal physical therapy is incorporated. Progression is best individualized based on a given patient’s specific needs, pain level, physical examination, functional progress, and the development of any complications during the postoperative course. Precautions and contraindications to rehabilitation progression can include signs of infection, delayed wound healing, neurovascular complications (i.e., deep vein thrombosis [DVT]), increased laxity of the Achilles/possible re-rupture, and increased swelling, redness, or pain.