Calf Augmentation

Calf augmentation is a procedure performed to enhance the lower portion of the leg. In people with a shrunken lower leg, as a result of injury or disease, an implant can be inserted in the calf to help minimize the resultant deformity. Despite the fact that actual leg function has not been improved, the authors consider this reconstructive surgery as the goal is to help restore a more normal appearance.

Some people have a naturally thin or underdeveloped calf, and despite exercise or diet, this leg remains small. These patients may request calf augmentation for pure aesthetic or cosmetic reasons. Women may desire only the medial or inner leg filled out. Body builders may want both the inner and outer lower leg filled out.

Calf augmentation usually is performed by placing an implant made out of silicone rubber over the muscles, on the medial aspect of the calf. Some people, such as body builders, may require a larger augmentation, and in these individuals an implant may be placed on both the medial (inner) and lateral (outer) aspects of the calf.[1, 2]

The authors performed their first calf augmentation in 1972 on an equestrian who desired a larger calf to fill out her riding boot. At that time, no custom silicone or gel implants were available. Consequently, the first 6 calf augmentations were performed with implants carved out of silastic foam, which was available in large blocks. Shortly thereafter, Dow Corning and other manufactures began making silicone rubber implants. The authors then started to use these implants, as did Glitzenstein and South American surgeons.[3] The authors' team used silicone gel implants in the mid 1970s and early 1980s but they have returned to using silicone rubber. Silicone gel implants remain broadly used in Mexico and South America.[4]

Frequency

Exact numbers are impossible to obtain, but calf augmentation is quite common in Mexico and Central and South America. It is less common in Canada and the United States. Unfortunately, many orthopedic surgeons and family physicians who see patients with a deformed or hypoplastic leg are not aware that augmentation can be performed.

Some patients have a relative disproportion between the thigh and the calf. The legs are symmetric, the thigh is in proportion to the rest of the body, but the calf is relatively underdeveloped. These patients simply want their legs built up to be more in proportion with the rest of their body. Body builders want to augment the gastrocnemius muscle on the inside and outside since that muscle does not become bulky in some individuals.

Table 1. Etiology of the Hypoplastic Leg (Open Table in a new window)

In a patient who desires cosmetic augmentation, the indication for calf augmentation is a relative disproportion between the thigh and the rest of the body and the calf. The patient with a hypoplastic leg often has other coexisting deformities. A significant discrepancy of the leg length and/or bone volume may exist, deformities of the foot and ankle may be present, and even the skin and soft tissues may be relatively hypoplastic. These patients often have had multiple surgical procedures on the lower leg, which may limit size or placement of the implant. This is especially common in patients with polio or congenital foot deformities. Warn these patients that in most situations, exact symmetry is not achieved but a significant improvement can be made, and the defect may not be obvious to the casual observer.

The implant is placed on the medial surface of the superficial posterior compartment of the leg, which contains the gastrocnemius, soleus, and plantaris muscles. Enter this compartment through an incision in the popliteal crease, dividing skin and subcutaneous fat and incising deep investing fascia of the leg, which is thickened to form the popliteal fascia on top or bottom of the fascia.[5] The semimembranosus and the more lateral semitendinosus tendons lie superficial to the medial head of the gastrocnemius muscle and must be retracted medially. The lateral borders of the popliteal fossa, biceps femoris, and lateral head of the gastrocnemius muscles are encountered if augmentation is carried out more laterally with a second implant.

The thin fascia overlying the gastrocnemius muscle is identified, and the raphe that separates the two heads of the gastrocnemius muscle is often visible. The implant should be resting on the medial gastrocnemius muscle and its epimysium. The short saphenous vein runs in the mid line posteriorly, deep to the deep invested fascia and along the superficial surface of the gastrocnemius muscle. It enters the popliteal vein higher up in the popliteal fossa. Care must be taken not to damage this vessel or the medical sural cutaneous nerve.

Some surgeons place the implant behind the muscle. Anterior to the point of approach lies the long saphenous system, with which the surgeon should not interfere.

Contraindications to calf augmentation include unrealistic expectations, severe medical problems, and compromised circulation to the skin and soft tissues of the lower leg.

Assess the patient's goals and expectations. If a patient who is a body builder desires the insertion of too large an implant and the surgeon feels this cannot be achieved without creating too much internal pressure in the leg, the patient should be discouraged from undergoing the procedure. Similarly, a patient with a hypoplastic leg who thinks that the postpolio leg can be reconstructed to look like the normal leg is also not a candidate for the procedure.

Obviously, patients who have circulatory problems or other severe medical problems pertaining to the legs should not undergo the procedure.

Carry out the standard history and physical examination, as for all surgery. Perform the necessary laboratory tests and blood work.

On some patients, the authors use a moulage on the leg, which is available from most companies who manufacture leg implants. Premade sizers (that are the same size as manufactured implants) can be inserted inside a long stocking. This is performed in front of a mirror so the patient can advise the surgeon as to the size of calf he or she prefers. This gives the surgeon insight into the expectations of the patient and whether surgery is feasible. This is especially true for cosmetic augmentation of the underdeveloped leg or the leg of a body builder. It also allows the surgeons to create the size of implant that can be used to reconstruct the hypoplastic leg. It allows the surgeon and patient the opportunity to see whether the desired size of implant is close to one of the standard manufactured implants or whether a custom implant must be made. If a custom-made implant must be created, the cost is significantly greater.

Prior to surgery, prepare the legs with an antibacterial solution. Male patients generally are shaved.

See the list below:

• The authors prefer to perform the procedure under general anesthesia, but an epidural or local anesthesia also can be used.

• For medial calf augmentation alone, the patient is in a supine position. With a 4-quadrant augmentation, such as in a body builder, the patient is in a prone position.

• Make a transverse incision approximately 4 cm long in the most dominant crease in the popliteal fossa. When performing only a medial calf augmentation, place the incision more medially. When performing a 4-quadrant augmentation, place the incision in the mid position of the popliteal fossa.

• Carry the dissection through the subcutaneous fat and fascia down to the popliteal fascia. Open the popliteal fascia and carry the dissection medially toward the tibia, underneath this thick fascia. This popliteal fascia can have several layers; make sure to get below the last layer of this fascia.

• Then carry the dissection bluntly out toward the tibia, staying below the semitendinosus and semimembranosus tendons. This can be performed with a finger.

• The popliteal fascia becomes confluent with the deep investing fascia of the leg. The deep investing fascia inserts into the anterior border of the tibia, down to the transverse malleolar ligament and into the posterior raphe.

• Once below this deep investing fascia, on top of the gastrocnemius muscle, a large blunt dilator then can be used to create the pocket on top of the muscle. Leave behind fascia on top of the muscle. This is a very avascular pocket, and problems with bleeding are rarely encountered.

• If dissecting out the lateral pocket, perform a similar type of dissection. Carry dissection out through the popliteal fascia, out under the deep investing fascia of the lateral aspect of the posterior superficial compartment, and on top of the lateral gastrocnemius head.

• Once the pocket is created, irrigate appropriate antibiotic solution. Buckle the implant onto itself and insert it. Ensuring that the edges of the implant are unfolded after insertion is important.

• After the implant has been inserted, check it to ensure that it lies flat against the muscle. Carry out a careful 3-layered closure of the wound. Close the popliteal fascia, followed by the subcutaneous fascia and the skin.

• Place a dressing of nonadherent gauze over the incision site and wrap the entire leg with a 4-inch adhesive stretch tape put on in sections. Do not wrap the leg continuously, since it is essential that the bandage is not put on too tightly. Then place a tensor bandage over the adhesive bandage.

• Administer 1 g cephalosporin antibiotics (or, if allergic to penicillin, clindamycin 300 mg IV preoperatively).

  Calf augmentation. Fascia on top of muscle.

Reconstruction of the hypoplastic leg

When the authors began reconstructing hypoplastic legs in the 1970s, they inserted as large an implant as they believed could be used safely. They then performed a further augmentation approximately a year later by placing a second implant behind the previous implant or a newer larger implant. In other words, they performed a serial augmentation of the calf. When Radovan developed the mammary expander, it was used to help expand the pocket in the leg. This allowed expansion of the upper portion of the leg but inadequate expansion of the lower leg occurred. Consequently, the authors developed their own expander, which is 22 cm in length, 8 cm in width in the upper portion, and 6 cm in the lower portion. A loop is attached to the inferior portion of this expander to facilitate insertion.

• Create the pocket in the hypoplastic leg in the same manner as for the cosmetic leg.

• Fill the expander with approximately 50 mL of normal saline. Then tie a heavy absorbable suture to the loop in the lower end of the expander and thread the other end of the suture through the eye of the long Keith needle, which is similar to a heavy Kirschner wire with a hole or "eye" in each end.

• Pass the needle from above through the pocket that has been created, being careful to stay in the space of the pocket and not to perforate into the muscle or the deep investing fascia when proceeding down into the pocket. If difficulty is encountered, the authors then hold a plastic cap on the end of the advancing needle tip. The plastic cap is secured by 2 sutures, which are held in the controlling hand.

• Once the needle is at the desired position, approximately 2 cm above the medial malleolus, pull the cap off and press the needle out through the skin. Traction on the needle then pulls the expander smoothly into the pocket as it is pushed in from above.

• Use the hands to manipulate the expander into position so that it lies smoothly and wrinkle free in the space created. Once the proper positioning is achieved, cut the catgut suture at the skin edge while under tension.

• Insert the expander port subcutaneously behind the knee. Carry out layered closure as in the standard cosmetic leg augmentation.

• Insert further saline through the expander port to ensure that the system is functional. Cover the leg with cotton and a tensor.

• Perform expansion of the leg every 7-10 days. In some severe postpolio legs that are small and have had several orthopedic procedures, expansion may require 3 or 4 months and is performed until the lower leg is overexpanded approximately 1 cm. Move the expander and insert the final prosthesis.

• If the implant is too large, trimming can be performed with a hot scalpel (Shaw) or a pair of heavy scissors. Carrying out the trimming very smoothly is important so that no irregularities below the skin occur.

• Perform closure and dressings as for aesthetic patients.

See the list below:

• For the first 12-14 hours postoperatively, the patient is on bed rest with bathroom privileges. The legs are kept elevated, and some flexion of the knee is allowed if the patient finds it more comfortable.

• Most patients experience a moderate amount of pain during the immediate postoperative phase, and narcotic analgesics usually are required. However, if the patient reports excruciating or steadily increasing pain, split the bandage.

• Routinely, patients are kept overnight, and ambulation with crutches is allowed the following morning. Instruct patients to wear a shoe with a wide-based heel at a comfortable level, usually 1.5 inches. This varies from patient to patient.

• Leave the initial dressing for 1 week. Then remove the dressing and place the patient into a firm antiembolic stocking with a Spandex rating of 26-34 mm. Maintain this support for 5 weeks to keep the implant compressed against the gastrocnemius muscle. This prevents dead space, helping to reduce seroma formation.

• During the first week, encourage patients to ambulate at home to take care of themselves. In the second week, they go for short walks and may resume sedentary work. If work entails standing for long periods of time or heavy lifting, the authors advise they take 3 weeks off work.

• Unrestricted exercise activity, even downhill skiing and equestrian sports, are permitted after 8 weeks.

Pressure problems

In the authors' series of 670 legs, three serious problems occurred. In 1986, one female patient developed an anterior compartment syndrome in one leg because the circumferential bandage was too tight. The patient had been discharged home prior to the development of the problem. She developed a subsequent foot drop and anterior compartment syndrome. She had to be treated by removal of the implant and fasciotomy. Fortunately, she regained total function.

The second patient was a body builder into whom 4 large implants were inserted, creating a tight leg. He developed pain postoperatively and while compartment pressure measurements were normal, the implants were removed. He went on to develop some mild muscle necrosis and underwent drainage for 4 weeks.

In the third patient, a bilateral calf augmentation was carried out. The patient had severe postoperative pain and consequently was taken back to the operating room. The implants were trimmed down and the space was felt to be very adequate. Pain persisted and the implants were removed. Compartment pressure tests results were normal. In spite of this, the patient went on to develop anterior compartment syndrome, which was released. Following this, the patient developed some clawing of her toes.

If the patient has pain in the leg while at rest the day after surgery, take down the dressing and examine the leg. If any skin change, swelling of the ankles, or evidence that the leg is too tight is found, then remove the implant. This prevents compartment syndrome or minor skin necrosis.

Skin slough

In 1976, the authors experienced a small skin loss along the line of closure in a postpolio reconstruction.[6] Beyond this instance, no skin necrosis has occurred. In 1980, the importance of staying below the deep investing fascia of the leg became apparent. The superiority of the fasciocutaneous flaps versus random cutaneous flaps is well established. If the integrity of the deep investing fascia is maintained, one is in essence creating a large fasciocutaneous flap. If the implant is of appropriate size and placed below the deep investing fascia, vascularity should not be a problem.

If the patient reports pain while the leg is at rest the day after surgery, remove dressings and examine the skin. If blistering of the skin is observed, then a vascularity problem is present, and, in all probability, the integrity of the deep investing fascia has been violated and vascularity jeopardized. Remove the implant immediately.

Hematoma

Treatment for hematoma is the same as for any other surgical procedure. Prompt evacuation, washing out, and reimplantation can be carried out.

Infections

In the authors' series, 1 patient developed an infection with Staphylococcus aureus, which necessitated the removal of the implant until the infection had subsided. This patient was treated in 1978, before routine prophylactic antibiotics.[6]

Seroma

To date, seroma, which occurs in 6%, is the most common problem encountered with calf augmentation. This presents as a swelling or asymmetry in the postoperative period. Percutaneous aspiration usually solves the problem. If seroma is recurrent, expect that the implant is not lying flush against the gastrocnemius muscle. This may be because the implant is buckled upon itself or was improperly carved. Treatment in these circumstances involves repositioning or replacing the implant.

Edema

In the immediate postoperative period, edema of the foot may be an indication that the dressing is too tight. Split the bandage. Prolonged edema due to the alteration of the lymphatic system has not been observed in the authors' series.

Sensory changes

This is an unusual sequence, which occasionally lasts as long as 4 weeks. Some decreased or altered sensation had been noted in the distribution of the sural nerve and the long saphenous nerve. No treatment is required, but the patient needs to be reassured that the sensory changes are temporary and resolve on their own.

Scar hypertrophy and pigmentation

Scar hypertrophy or hyperpigmentation in dark-skinned people can be observed here as elsewhere following surgery.

Implant show

In the cosmetic implantation, if the implant is placed below the deep investing fascia, the edge of the implant commonly is not seen. However, in the reconstructed leg, such as the very hypoplastic postpolio leg, where a large implant is placed to gain symmetry with the contralateral leg, edge of the implant show can be common.

Late sequelae

As with any embedded foreign body, capsule formation occurs.[7] The authors had a patient who reported some firmness in one leg 26 years after augmentation of her calves. Radiologic evidence revealed calcification of the capsule, which is frequently observed following breast augmentation. Exploration was carried out, and extensive calcification around the capsule was found, which was removed. Reimplantation was performed. This settled, but the patient had a protracted course of seroma formation with multiple aspirations.

A second patient also was seen with partial calcification of the capsules bilaterally 25 years postoperatively. This was treated by removal and reimplantation.

Another patient reported discomfort and swelling of one leg 18 years after bilateral calf augmentation. CT revealed a capsular contracture on that side. Exploration revealed a very thick capsule. The implant was removed, and biopsy and cultures revealed no pathogen. The only significance in her history was that 4 months prior she had a severe respiratory infection, which required hospitalization and antibiotic treatment.

A study by Pereira et al indicated that silicone-filled implants are safe and effective for cosmetic calf augmentation. The study involved 53 patients (40 women and 13 men) aged 25 to 51 years who underwent bilateral calf augmentation for cosmetic purposes, with asymmetrical-base, smooth-surface silicone elastomer implants (70 mL, 125 mL, or 175 mL) used in the procedures. Three patients required drainage through partial skin incisions for unilateral seromas, while four patients developed bilateral hypertrophic scars. However, no cases of infection, hematoma, compartment syndrome, deep venous thrombosis, or pulmonary embolism occurred, and no patients experienced implant rotation or displacement. Implant removal was performed at the request of one patient.[8]

At 12-month follow-up, 73% of the study’s patients described their postaugmentation appearance as “very good” to “excellent,” and 19% rated their appearance as “good,” with just 8% of patients considering their appearance to be less than good.[8]

As the originators of the operation, the authors have been asked to review many problem cases. These cases entailed skin slough and neuromuscular problems. In the authors' opinion, the cause in these cases was insertion of too large an implant. In most procedures, this led to a tight leg with subsequent development of lymphatic and venous obstruction and the consequential effects on the neuromuscular system. Inadequate postoperative care has led to further complications. As soon as the compartment is recognized as too tight, the implant should be removed, trimmed down, and reinserted or left out for another day.

In the cases in which skin loss has been a problem, the authors believe violation of the deep investing fascia occurred, disrupting the ideal fasciocutaneous coverage of that implant. Alternatively, the implant may have been too large, thus impinging on the circulatory system. As soon as this is recognized, the implant should be removed and replaced at a later date.

A study by Mundinger and Vogel indicated that autologous fat grafting may provide an alternative to implants in calf augmentation for congenital calf discrepancies and pseudo-varus deformity. In 13 patients who underwent the grafting procedure, the investigators found the augmentation to be durable and calf contour to be improved, at mean 19.6-month follow-up.[9, 10]

A retrospective study by Andjelkove et al indicated that composite calf augmentation, in which fat grafting is combined with implant use, is a safe procedure, with none of the report’s patients developing compartment syndrome. However, the investigators found high muscle sensitivity to post-augmentation pressure increase, leading them to support subcutaneous fat grafting.[11]

Conclusions

After 3 decades of working with the procedure, on more than 600 legs, the authors conclude that if the parameters outlined in this article for calf augmentation are followed, the operation is as satisfying as breast augmentation. The patients on whom the procedure has been carried out experience the same improvement in body image as have many of the patients on whom the authors have preformed breast enlargement. Patients who have undergone reconstruction of hypoplastic legs, such as those with polio, achieved the same satisfaction as patients who underwent breast reconstruction following removal for cancer.