Repair of a Ruptured Achilles Tendon

Acute rupture of the Achilles tendon is a common soft tissue injury, occurring more frequently in men than in women, 30 to 50 years old, who intermittently participate in exercise or athletic activities.3,46,117 The rupture usually is associated with a forceful concentric or eccentric contraction of the gastrocnemius–soleus muscles (triceps surae) during sudden acceleration or abrupt deceleration, such as jumping or landing.5 Degenerative and mechanical factors appear to increase the risk of acute rupture, including decreased strength or flexibility of the plantarflexors, excessive body weight, pre-existing tendinosis, corticosteroid injections into the tendon, and decreased vascularity of the tendon.5

The tendon often ruptures proximal to the distal insertion of the tendon on the calcaneus.34 At the time of injury a complete rupture leads to pain, swelling, a palpable defect, and significant weakness in plantarflexion. It also is associated with a positive Thompson test (absence of reflexive plantarflexion when the patient is prone-lying with the foot over the edge of a table and the calf is squeezed).106

A complete rupture of the Achilles tendon can be managed conservatively with extended cast immobilization or functional bracing; or it can be managed surgically. There is general agreement in the literature and in clinical practice that surgical intervention is routinely recommended for the young, active patient less than 30 years of age but that nonoperative management is the better option for the sedentary patient older than 50 to 60 years of age.3,46,117 Furthermore, surgery is considered the only option for the symptomatic patient with a chronic rupture in which the diagnosis or treatment was delayed for 4 weeks or more. 71,114 However, there is lack of agreement in the literature and in practice as to which is the better option for the middle-aged population.

Several recently reported systematic reviews and meta- analyses of the literature that included only prospective, randomized and quasi-randomized studies have revealed there is insufficient evidence to indicate which option is the better treatment strategy or yields better outcomes. 3,46,117 Both options have advantages and disadvantages. With surgical repair there is a lower rate of re-rupture of the tendon than with nonoperative management, but there also is a risk of wound closure problems, infection, and nerve injury with surgery. Nonoperative management requires a longer immobilization and recuperative time and is associated with a higher rate of deep vein thrombosis (DVT).3,11,46,117 Both patient and surgeon must weigh the different advantages and disadvantages in the decision-making process.

Indications for Surgery

The following are frequently cited indications for surgical repair or reconstruction of an acute or chronic rupture of the Achilles tendon.

Acute, complete rupture of the Achilles tendon5,10,11 Chronic, previously undiagnosed or untreated complete rupture in which end-to-end apposition cannot be

achieved by conservative means.72,114 Typically indicated for the active individual who wishes to return to high-demand functional

activities.3,11,117

Procedures

There are a considerable number of surgical procedures and techniques for repair or reconstruction of a ruptured Achilles tendon. 5,10,11,68,69,114,117 An open or percutaneous approach can be used for a primary repair.15,61,100

Primary repair of an acute rupture is performed within a few days to a week after the injury and usually is carried out with a direct, end-to-end repair in which the ends of the torn tendon are reopposed and sutured together.5 the repair site may or may not be reinforced by some method of tissue augmentation. Delayed repair of a chronic rupture requires reconstruction and augmentation of the tendon most often by an autograft, or tendon transfer, or possibly an allograft. 71,114 Structures that may serve as a donor graft are the flexor hallucis longus, plantaris, or peroneus brevis tendons or a flap of fascia from the gastrocnemius muscle.

In an open primary repair, a posterior incision is made at the distal leg just medial to the Achilles tendon. Placing the incision medial of the tendon avoids possible damage to the sural nerve. The tendon ends are identified, frayed fibers are removed, and the ends reopposed and sutured together while the ankle is maintained in a neutral to slightly plantarflexed position.5 With a tendon reconstruction a second incision is made to harvest the donor graft. If, for example, the flexor hallucis longus (FHL) tendon is selected, an incision is made along medial aspect of the sole of the foot at the mid-metatarsal level. A sufficient portion of the FHL tendon is left distally so the remaining portion can be sutured to the flexor digitorum longus tendon to retain active flexion of the first toe.114 The harvested portion of the FHL tendon then is woven into and sutured to bridge the gap of the Achilles tendon ends.

Before closure, the ankle is moved through the ROM to assess the stability of the repair or reconstruction. A compression dressing and below-knee posterior splint are applied after closure with the ankle usually positioned in15° to 20° of plantarflexion.5,114 If immediate or very early postoperative weight bearing is to be allowed by the surgeon, the ankle is placed in a neutral (0° of dorsiflexion), if possible, and stabilized with a rigid anterior splint.43

NOTE: An above-knee cast is applied (and later replaced with a below-knee cast) if the rupture occurred at the myotendinous junction or the quality of the repair is tenuous.

Postoperative Management

Although guidelines for postoperative rehabilitation after an open repair of an acute Achilles tendon rupture vary considerably in the literature and in clinical practice, these guidelines tend to fall within two categories—use of a conventional (traditional) management strategy or an early remobilization approach. The use of immobilization and the initiation of weight bearing distinguish one approach from the other. Guidelines for management after percutaneous repair are not addressed in the following sections but can be found in other resources. 15,61,100

Immobilization and Weight Bearing Considerations

Conventional approach. After an open primary repair of an acute Achilles tendon rupture, conventional postopera-tive management, a widely used practice for many years, involves approximately 6 weeks of continuous immobilization with the ankle held in plantarflexion at least a portion of that period of time.3,5,11,63,67 The patient remains non- weight bearing on the operated extremity during this time. After a delayed tendon reconstruction with graft augmentation for a chronic rupture, the time before motion and weight bearing are permissible is longer, usually an additional 2 weeks or more.114

Table 22.2 summarizes immobilization and weightbearing guidelines associated with conventional management after primary Achilles tendon repair.3,5,11,63,67,68 Although this approach is safe and associated with low risk of rerupture, extended immobilization, traditionally thought to be necessary to protect the healing tendon, has been shown in some studies to lead to deficits in strength, particularly in the plantarflexors, and loss of ROM of the ankle.9,68,100

Early remobilization approach. For the past two decades or more there has been a trend to decrease the period of continuous postoperative immobilization and to initiate early ankle ROM in a protected range and early weight bearing in a functional orthosis.9,34,43,63,64,67–69,82,97 This approach, sometimes termed “functional rehabilitation,” is an option after primary repair of an acute rupture, not a delayed reconstruction. Early motion and weight bearing are possible because of advances in surgical procedures, such as stronger suturing techniques and sometimes the

use of soft tissue augmentation to reinforce the primary repair. 10,43,64,68,69,97 Although published recommendations for early protected motion and weight bearing vary widely, use of a below-knee (boot-like) dorsal functional brace or splint is a consistent feature of early remobilization approaches. If bracing is prescribed, it is a hinged, controlled ankle motion (CAM) orthosis that can be locked in various positions.82 When ankle motion is permissible, the orthosis is adjusted to allow movement but only in a protected range, typically limiting dorsiflexion beyond neutral.9,34,67 If a rigid splint is used, its dorsal configuration limits dorsi flexion to 0but allows plantarflexion.43,63

Initially, the brace or splint holds the ankle in slight plantarflexion but is adjusted (or refabricated in the case of a splint) to neutral by 2 weeks postoperatively.13,34,63 During the first 6 weeks of rehabilitation the protective

orthosis is worn during ambulation and at all other times except when removed for wound care and selected exercises.

When the patient is able to ambulate on level surfaces without pain while bearing full weight on the operated extremity, the protective boot or splint is discontinued (usually by 8 to 10 weeks postoperatively). As with a conventional approach, after discontinuing the functional brace or splint, many surgeons prescribe a 1.0- or 1.5-cm heel lift for both shoes that are worn for several weeks to decrease ground reaction forces during functional activities.68

The guidelines for initiating and progressing weight bearing and ROM exercises recommended in published programs differ from study to study. A summary of these guidelines is presented in Box 22.5. 43,63,67,82 Common to all early remobilization programs is the use of safe levels of applied stress while protecting the healing tendon. Close communication among the surgeon, therapist, and patient is essential for success with this approach to postoperative management.

Focus on Evidence

Although there have been few randomized studies directly comparing a functional bracing or splinting and early motion program after acute Achilles tendon repair with a program of extended cast immobilization (usually 6 weeks) followed by ROM exercises, a recent meta-analysis of these studies demonstrated that patients managed with an early motion/functional bracing program had a significantly lower rate of adhesion formation and limited ankle ROM. However, the investigators noted that the pooled data from the available studies must be interpreted with caution because of the variety of postoperative regimen used.46

Exercise

After open, primary repair of an acute Achilles tendon rupture, the types of exercise included in a postoperative program are similar regardless of whether an early motion/early weight-bearing approach or a conventional (extended immobilization/delayed motion and weight bearing) approach is employed. What is different is the timing and progression of the exercises based on when ROM and weight bearing are permissible.

In the sections that follow a progression of exercises designed to assist a patient achieve a number of treatment goals and ultimately function at the pre-injury level is presented.

BOX 22.5 Features of Early Remobilization Programs After Repair of Acute Achilles Tendon Rupture*Weight-bearing Guidelines• Initiated as tolerated while using crutches immediately after surgery43,63 or after 2 weeks67,82 in a below-kneE orthosis with the ankle immobilized most often in plantarflexion or possibly neutral• Progress gradually to full weight-bearing status between 3 to 6 weeks postoperatively43,82• Orthosis worn during all weight-bearing activities for 6 to 8 weeks after surgery82• Full weight bearing without the functional orthosis but wearing regular shoes with bilateral heel lifts when orthosis discontinued

beginning at about 6 to 8 weeks postoperatively43,101ROM Exercises• Immediately43,63,64,97 or by 1 to 2 weeks67,82,101 after surgery, active plantarflexion and dorsiflexion of the ankle initiated while wearing a dorsal functional brace or splint to prevent dorsiflexion beyond 15to 30of equines or to no more than a neutral position while seated or supine• By 6 to 8 weeks dorsiflexion to 10 permitted in the orthosis and inversion/eversion out of the orthosis43,67

Exercise: Maximum Protection Phase

Achilles tendon repair frequently is performed on an out-patient basis. Therefore, patient education is essential before surgery or prior to discharge. It focuses on wound care (if the immobilizer is removable), controlling peripheral edema by elevating the operated leg, gait training, and a home exercise program. The following treatment goals and exercises are appropriate during the first 4 to 6 weeks after surgery.

Maintain ROM of nonimmobilized joints. Perform active ROM of the hip, knee, and toes of the operated lower extremity while the patient is wearing the immobilizer.

Prevent reflex inhibition of immobilized muscle groups. If early ROM is not permitted, begin submaximal, pain-free muscle-setting exercises of the ankle in the immobilizer within the first few days after surgery. Start with setting exercises of the dorsiflexors, invertors, and evertors. At 2 weeks, add setting exercises of the plantarflexors.

Prevent joint stiffness and soft tissue adhesions in the operated ankle and foot. If an early motion and weight-bearing approach was planned, begin the ROM exercises described in Box 22.5 within a few days to 2 weeks after surgery. The time frame is determined by the surgeon.

Maintain cardiopulmonary endurance. Use an upper extremity ergometry for endurance training, if available.

Exercise: Moderate Protection Phase

By 6 weeks postoperatively the patient may be permitted to bear weight as tolerated on the operated extremity regardless of whether an early weight-bearing program or conventional program was implemented. However, a functional CAM orthosis is required during progressive weight-bearing activities for several weeks.

During this phase of rehabilitation, which usually extends from 6 to 12 weeks postoperatively, gradually increasing stress is placed on the operated tendon and surrounding structures. Patients typically begin a supervised exercise program at this time.

PRECAUTIONS: Progress all exercises very cautiously that place resistance or a stretch on the gastrocnemius-soleus muscle group. Postpone closed-chain exercises until the patient is able to bear full weight on the operated side without pain. Avoid any high-impact, high-velocity activities to minimize the risk of re-rupture of the Achilles tendon.

• Increase ROM of the operated ankle. Begin gentle self-stretching exercises in nonweight-bearing and weight-bearing positions. Stretch the gastrocnemius–soleus muscle group with the knee extended and flexed. Examples of stretching activities are:

o Grade III joint mobilization techniques if ankle or foot joints are restrictedo Gentle manual stretching to increase inversion/eversion and dorsiflexion/plantarflexiono A towel stretch to increase dorsiflexiono While seated, active ankle ROM with the foot resting on a small rocker or wobble boardo Standing stretch to increase dorsiflexion with the knee flexed and extendedo Descend stairs step over step as ROM improves

• Improve strength of the operated lower extremity. Initiate open- and closed-chain, low-intensity resistance exercises at 6 to 8 weeks. Examples include.

o Open-chain resistance exercises of the ankle against a light grade of elastic resistance.o Bilateral, progressing to unilateral closed-chain activities, such as heel and toe raises while seated,

mini- squats alternating heel raises and toe raises, and partial lunges using body weight as resistance.

• Re-establish balance reactions. Initiate proprioceptive training and balance exercises in double-leg stance of a firm surface. Progress to single-leg stance on a soft surface.

• Improve muscular and cardiopulmonary endurance. Begin and gradually progress level-surface treadmill walking or stationary cycling (recumbent or upright) while wearing the functional, hinged orthosis, if required, or regular shoes with a heel lift. Raise the seat height of the upright bicycle to accommodate for limited dorsiflexion. Progress to treadmill walking on an incline.

Exercise: Minimum Protection/Return to Function Phase

• The final phase of rehabilitation, which begins around 12 to 16 weeks postoperatively, is directed toward returning a patient to a pre-injury level of function for expected work- related demands and desired recreational/athletic activities. Stretching exercises continue until full ROM is achieved, and then the patient transitions to a maintenance program. Eccentric resistance exercises of the gastrocnemius–soleus muscle group in weight-bearing positions and eventually plyometric training are added to the strengthening program. More challenging proprioceptive training is added. Jogging, running, agility drills, and sport-specific training usually can be initiated at 16 weeks. Patient education focuses on ways to reduce the risk of rerupture of the repaired tendon, such as warming up before strenuous activity and daily stretching. Most patients are permitted to resume sports gradually at 5 to 6 months if the strength of the operated extremity is relatively comparable to that of the contralateral extremity.

OutcomesThe ideal outcome is for a patient to return to a pre- injury level of physical activity without pain or re-rupture of the repaired Achilles tendon. Patients undergoing primary repair of an acute rupture have consistently better outcomes than those who undergo a delayed repair for a chronic rupture. The longer the delay between injury and repair, the poorer the results.114 The patient population with the highest risk of re-rupture after primary repair of an acute rupture are active individuals 30 years of age or younger.82Comparison of methods of management. The results of numerous studies

comparing methods of management of acute tendon ruptures have been reported. Methods compared include operative and nonoperative management, open and percutaneous procedures, and conventional and early motion/early weight bearing approaches to postoperative treatment. Outcomes typically reported are rate of rerupture, ROM, strength, functional or sport-related activity level, and patient satisfaction. Some generalizations can be drawn from systematic reviews of the literature and individual studies.

When comparing outcomes of nonoperative (cast immobilization) with operative management of acute ruptures, three systematic reviews and meta-analyses of the literature have revealed that there is a significantly higher rate of re-rupture associated with nonoperative management than with surgical repair.3,46,117 The authors of one of these reviews of randomized trials concluded that there is a three times higher risk of re-rupture after nonoperative treatment than after surgery. However, excluding re-rupture, operative management is associated with a substantially higher rate of complications than nonoperative treatment, including infection, adhesions, and nerve injury. 46 The authors of another one of the reviews noted that when patients who sustain a re-rupture are excluded from an analysis of outcomes of nonoperative and operative management, long-term results, including activity level, ROM and strength, are similar.3

Comparison of open repair with percutaneous repair indicates no significant difference in the rate of re-rupture between the two techniques, but a higher rate of infection occurs with open repair61 and a higher rate of sural nerve damage occurs with a percutaneous approach.117

Rehabilitation using early motion and weight bear- ing appears to be as safe as management with prolonged cast immobilization and delayed weight bearing. Early follow-up studies have indicated no increased incidence of tendon rerupture with early postoperative motion. 9,44,64,68 Although early reports are promising, no determination can yet be made on whether early motion and weight bearing enables a patient to return to a full level of functional activity sooner than if managed with a conventional postoperative approach.44,64,68 However, authors of a systematic review of the available studies concluded that open repair followed by early motion and weight bearing is probably the treatment of choice and leads to better outcomes for active patients.117

Kisner, C., & Colby, L.A.(2007). Therapeutic Exercise Foundation and Techniques (5 th ed.). Philadelphia, PA: FA Davis