# Achilles Tendon Rupture: Operative vs. Nonoperative Management ## Introduction Acute Achilles tendon rupture is the most common tendon rupture in the body, with a rising incidence attributed to increased participation in recreational sports among middle-aged adults. The optimal management remains one of the most debated topics in orthopedic surgery, with high-quality evidence supporting both operative and nonoperative treatment when combined with early functional rehabilitation. ## Epidemiology The annual incidence is approximately 18 to 31 per 100,000, with peak incidence in the 30 to 50 year age group. Males are affected approximately 5 times more frequently than females. Rupture typically occurs during recreational sports such as basketball, tennis, and soccer that involve sudden acceleration, deceleration, or pushing off. The rupture zone is 2 to 6 cm proximal to the calcaneal insertion, corresponding to the area of poorest vascularity known as the watershed zone. Risk factors include fluoroquinolone antibiotics, corticosteroid use (both systemic and local injection), diabetes, chronic kidney disease, and prior tendinopathy. ## Mechanism and Pathology Rupture typically occurs during eccentric loading of the gastrosoleus complex, and most ruptures occur in tendons with pre-existing degenerative changes such as mucoid degeneration or hypoxic tendinopathy. The patient often describes a sensation of being kicked in the back of the leg or hearing a pop. Three mechanisms are recognized: pushing off with a weight-bearing foot, sudden unexpected dorsiflexion, and violent dorsiflexion of a plantarflexed foot. ## Clinical Diagnosis ### History The patient reports sudden sharp pain in the posterior calf during activity, with difficulty bearing weight and inability to push off. Prior symptoms of Achilles tendinopathy may or may not be present. ### Physical Examination A palpable gap or defect in the tendon is found 2 to 6 cm above the insertion. The Thompson test (Simmonds test) is performed with the patient prone, squeezing the calf to produce ankle plantarflexion; absence of plantarflexion is diagnostic of rupture. Increased passive ankle dorsiflexion compared to the uninjured side is noted. Weak but present plantarflexion may still exist via the long toe flexors and tibialis posterior, which can lead to missed diagnosis if the Thompson test is not performed. The Matles test, performed with the patient prone and knees flexed to 90 degrees, shows the affected foot falling into more dorsiflexion than the uninjured side. ### Imaging Diagnosis is primarily clinical, and imaging is not required in most acute cases. Ultrasound provides dynamic assessment of tendon continuity and gap distance and is useful when clinical diagnosis is uncertain. MRI provides detailed assessment of the rupture pattern, gap size, and tendon quality and is typically reserved for chronic or partial ruptures or when the diagnosis is in doubt. ## Nonoperative Management ### Indications Nonoperative management is indicated for low-demand or sedentary patients, patients with significant medical comorbidities such as diabetes, peripheral vascular disease, or immunosuppression, and patients who cannot tolerate surgery or anesthesia. It is increasingly used for all patients when combined with early functional rehabilitation. ### Protocol Initial treatment involves equinus positioning in a cast or boot with the ankle in 20 to 30 degrees of plantarflexion, with progressive decrease in equinus over 6 to 8 weeks using heel wedges. Early functional rehabilitation with range of motion exercises beginning at 2 to 4 weeks is critical to outcomes. Weight-bearing in a boot is typically initiated at 2 to 4 weeks, with return to full activity at 4 to 6 months. ### Outcomes Modern accelerated functional rehabilitation protocols report re-rupture rates of 4 to 5%, comparable to surgical repair. Functional outcomes are similar to operative treatment in several randomized controlled trials when early motion is employed. A slightly reduced peak plantarflexion strength (10 to 15% deficit) compared to operative repair has been reported in some studies. | Feature | Nonoperative (Functional Rehab) | Operative Repair | |---------|-------------------------------|-----------------| | Re-rupture rate | 4-5% (with early motion) | 2-4% | | Wound complications | None | 5-10% (wound healing, infection, sural nerve) | | Plantarflexion strength | 10-15% deficit in some studies | Slightly better peak strength | | Return to activity | 4-6 months | 4-6 months | | Best candidates | Low/moderate demand; comorbidities | Young, active, athletes; delayed presentation | | Key requirement | Early functional rehabilitation protocol | Experienced surgeon; compliant patient | ## Operative Management ### Indications Operative management is preferred for young, active patients with high functional demands, competitive or elite athletes, delayed presentations (more than 4 weeks) with significant gap, re-rupture after nonoperative treatment, and patient preference after shared decision-making. ### Open Repair Open repair is performed through a midline posterior incision with careful handling of the paratenon. A Krackow suture technique or modified Bunnell suture using nonabsorbable braided suture achieves end-to-end repair with appropriate tension setting, matching the resting ankle position to the contralateral side. Repair may be augmented with the plantaris tendon or turndown flaps of the gastrocnemius aponeurosis for chronic ruptures or poor tissue quality. Wound complications are the primary concern, including wound infection, skin necrosis, and sural nerve injury, with complication rates up to 5 to 10%. ### Minimally Invasive and Percutaneous Repair Minimally invasive techniques use smaller incisions with specialized instruments such as the Achillon device or PARS system. They carry a reduced wound complication rate compared to open repair. Sural nerve injury risk exists with percutaneous techniques (up to 10% in some series) but is mitigated by identifying the nerve or using mini-open techniques. Re-rupture rates are comparable to open repair, and this approach is gaining preference among surgeons as a compromise between open and nonoperative management. ### Postoperative Rehabilitation Modern protocols emphasize early weight-bearing and early motion within 2 weeks. Accelerated rehabilitation after surgical repair produces better functional outcomes than prolonged immobilization. The typical progression involves protected weight-bearing in a boot for 6 weeks, progressive strengthening from 6 to 12 weeks, and return to sport at 6 to 9 months. Eccentric strengthening using the Alfredson protocol is incorporated during the later rehabilitation phases. ## Evidence Summary: Operative vs. Nonoperative ### Key Trials Multiple randomized controlled trials (Willits 2010, Olsson 2013, Lantto 2015) have demonstrated no significant difference in functional outcomes between operative and nonoperative treatment when both groups undergo early functional rehabilitation. Re-rupture rates are comparable at 3 to 5% for operative and 4 to 6% for nonoperative treatment with functional rehabilitation. Operative treatment carries a 5 to 10% risk of wound complications not present with nonoperative management. Operative repair may offer a small advantage in peak plantarflexion strength and is preferred by elite athletes. ### Current Consensus Nonoperative management with accelerated functional rehabilitation is a viable option for the majority of patients. Operative repair is preferred for high-level athletes, patients with large gaps, and those who prioritize minimizing re-rupture risk. Shared decision-making incorporating patient activity level, risk tolerance, and occupation is paramount. ## Chronic and Neglected Ruptures Chronic ruptures, defined as those presenting more than 4 to 6 weeks after injury, involve significant tendon retraction and gap formation that preclude primary repair. Reconstruction options include V-Y gastrocnemius advancement for gaps of 2 to 5 cm, flexor hallucis longus transfer (the most commonly used augmentation for chronic ruptures), turndown flaps using a central strip of proximal gastrocnemius aponeurosis turned down to bridge the gap, and allograft augmentation for massive defects when autograft is insufficient. ## Clinical Pearls The Thompson test is the single most reliable clinical test for acute Achilles rupture, and residual plantarflexion from accessory muscles can lead to missed diagnosis if the Thompson test is not performed. Nonoperative treatment with early functional rehabilitation produces outcomes comparable to surgical repair for most patients, with the key being early motion rather than prolonged immobilization. If operative repair is chosen, minimally invasive techniques reduce wound complications while maintaining equivalent functional outcomes and re-rupture rates. Chronic ruptures greater than 4 to 6 weeks old with significant tendon retraction require reconstruction with FHL transfer or other augmentation techniques rather than primary repair. ## References 1. Willits K, Amendola A, Bryant D, et al. Operative versus nonoperative treatment of acute Achilles tendon ruptures: a multicenter randomized trial. *J Bone Joint Surg Am*. 2010;92(17):2767-2775. 2. Olsson N, Silbernagel KG, Eriksson BI, et al. Stable surgical repair with accelerated rehabilitation versus nonsurgical treatment for acute Achilles tendon ruptures: a randomized controlled study. *Am J Sports Med*. 2013;41(12):2867-2876. 3. Lantto I, Heikkinen J, Flinkkila T, et al. Early functional treatment versus cast immobilization in tension after Achilles rupture repair. *Am J Sports Med*. 2015;43(9):2302-2309. 4. Maffulli N, Via AG, Oliva F. Chronic Achilles tendon rupture. *Open Orthop J*. 2017;11:660-669.