Chou: OKU: Foot and Ankle 7

Chapter 23: Disorders of the Achilles Tendon

musculotendinous unit. The most common donor sites are the flexor hallucis longus (FHL), peroneal tendons, and flexor digitorum longus. Peroneus brevis tendon transfers were performed through a limited approach in 32 patients and all were able to work and participate in leisure activities. 26 Six were rated as having an excellent outcome, and 24 had a good outcome. Loss of eversion strength was found objectively on examination but was not subjectively reported by patients. The FHL tendon transfer has several reported advantages including limited donor morbidity, greater strength than a peroneus brevis transfer, an axis of pull similar to that of the Achilles tendon, and improved vascularity of the reconstruction with presence of the low-lying muscle belly 27 ( Figure 3 ). The use of a free tissue transfer such as a semitendino sus graft has had good results for the treatment of ten don gaps larger than 6 cm. 28 A study reported excellent results in 62 of 72 patients with a chronic rupture at the insertion of the Achilles tendon when the gastrocnemius aponeurosis was used to reconstruct the insertion. 29 Most studies of synthetic grafts have been small, and com parative evaluation therefore is difficult. Although sur gical treatment of chronic ruptures has led to improved outcomes, patients continue to have strength deficits in comparison with the contralateral limb. A variety of techniques have been studied, but the small numbers of patients, combined with variations in patient selection, gap measurements, postoperative regimens, and outcome measurements, create difficulty in comparing data and making firm recommendations. ACHILLES TENDINOPATHY Achilles tendinopathy is described as insertional or nonin sertional. Noninsertional tendinopathy is further classified as peritendinitis, peritendinitis with tendinosis, or tendino sis. Tendinosis is a chronic, noninflammatory, degenerative process of the tendon that is associated with decreased vascularity, repetitive microtrauma, and aging. The asso ciated etiologic factors can include diabetes, hypertension, steroid use, obesity, and estrogen exposure. Patients range from relatively young and active patients with peritendi nitis caused by overuse to patients older than 50 years with tendinosis combined with peritendinitis of varying severity. Patients with peritendinitis have diffuse swelling and tenderness along the course of the tendon. Patients with tendinosis typically have pain and swelling along a nodular area within the tendon. Tenderness to palpation often is present along the area of tendon thickening. The patient may have difficulty performing a single-leg heel rise. MRI and ultrasonography can be useful for defining the location and extent of disease. Nonsurgical management is effective in 70% to 75% of patients. 30,31 Modalities including rest, NSAIDs,

Section 7: Tendon Disorders and Sports Related Foot and Ankle Injuries

activity modification, and eccentric strengthening fre quently are used. Immobilization in a short leg cast or boot may be beneficial if the condition is recalcitrant. Injectable therapies are gaining popularity for treating Achilles tendinosis, using agents such as platelet-rich plasma, autologous blood, sclerosing agents, protease inhibitors, hemodialysate, corticosteroids, and prolother apy. A systematic review of nine randomized controlled studies involving the use of injectable therapies found only one study meeting the quality criteria. 31 Most patients treated with an injectable therapy were found FIGURE 3 Intraoperative photograph showing the use of a harvested flexor hallucis longus tendon to treat a chronic Achilles tendon rupture. Copyright © Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. 2023

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Orthopaedic Knowledge Update ® : Foot and Ankle 7