Medial Thighs, Knees, and Anterior Thighs
Aesthetically, fat pads of the medial thigh and the medial knee are not isolated or separate from each other. Most thin patients have minimal fat midway between the knee and the proximal medial thigh. Most middle-age women have fat that extends over the entire extent of the medial thigh.
Liposuction over the entire contiguous area of the medial thigh and knee is preferred to treating the medial thigh and medial knee as isolated areas. More fat can be removed, and the results are consistently smoother than when the two areas are treated separately. Treating these areas as discrete or cosmetically separate often produces a distinct line of demarcation at the margin of the liposuction area. By treating the entire extent of the medial thigh and knee, the surgeon can minimize the incidence of a visible border zone between the proximal medial thigh and the medial knee.
An occasional male patient will benefit from medial thigh liposuction; the surgical technique is the same as for the female medial thigh. I have not done liposuction on the medial knee of a male.
Without tumescence, the medial thigh is one of the most difficult areas in which to achieve smooth results. The fat of the proximal medial thigh contains little fibrous tissue and has a soft, jellylike quality. Such fat may be liposuctioned too easily and rapidly, resulting in areas of excessive and irregular liposuction.
With tumescent anesthetic infiltration of the medial thigh and careful microcannular liposuction, the surgeon can consistently achieve complete and smooth results.
Gross Anatomy of Subcutaneous Fat. The subcutaneous fat of the medial thigh lacks significant fibrousness and thus has minimal antitypy (resistance to penetration). This fat becomes sparse along the sulcus at the medial thigh–perineum junction. The subcutaneous fat of the inner thigh is most prominent and deepest a few centimeters distal to the groin.
Distally the depth of medial thigh subcutaneous fat tends to diminish gradually and reaches its nadir in an area approximately two thirds the thigh’s length. Beyond the nadir, subcutaneous fat of the medial knee becomes prominent.
The greater saphenous vein courses superficially within the subcutaneous fat from the proximal saphenofemoral junction to the distal posteromedial condyle. The femoral artery is deep to the muscle and therefore relatively remote from the subcutaneous fat.
The muscles underlying the medial thigh are the proximal adductor group, sartorius, and semitendinosus.
Surface Anatomy. The distribution of subcutaneous fat is the principal determinant of human female surface anatomy. In certain areas, such as the medial and anterior thigh, acceptable liposuction results can be achieved only by using precise technique. In particular, detailed contour drawings of the medial thigh/knee are essential for accurate liposuction of the subjacent subcutaneous fat. In addition to concentric contour drawings, an infiltration grid with 8-cm (3-inch) squares is drawn. This grid helps the nurse or surgeon keep track of the areas being infiltrated with tumescent anesthesia (Figure 34-1).
Medial Thigh Furrow. A subtle but important linear depression or shallow furrow courses diagonally from the proximal anterior thigh distally over the medial thigh toward the posterior knee. Although the path of this furrow approximates the position of the sartorius muscle, the furrow is usually less prominent in thin women. The visibility of the medial thigh furrow is accentuated by accumulations of fat in the proximal medial thigh and the knee (Figure 34-2).
This furrow accentuates the appearance of obesity. The liposuction surgeon can diminish this visual effect by not highlighting the furrow with liposuction. More liposuction should be done within the proximal and distal compartments of fat (Figure 34-3).
Fat Compartment Access. The medial thigh fat pad gives the inner thigh a drumstick appearance. The area of greatest medial prominence is the area where the two thighs rub together.
The medial thigh, including the posterior aspect, is most easily accessed for liposuction when the patient is lying in the lateral decubitus position with uppermost hip flexed in the “high-step” position and uppermost leg resting on a supportive pillow (e.g., Thigh Aside) (Figure 34-4).
Posterior extension of the medial thigh fat compartment can be prominent and disproportionate in some women. The posterior portion cannot be easily or completely accessed for liposuction when the patient is supine (Figure 34-5). Surgeons who use systemic anesthesia often prefer not to move the patient from the supine position. They must therefore attempt, often unsuccessfully, to treat the entire medial thigh from the supine position.
Anterior extension of medial thigh fat pad extends onto the proximal anterior thigh in some women (Figure 34-6). When particularly prominent, anterior portion is best treated with the patient supine (Figure 34-7).
Younger women have prominent medial thigh fat and good skin elasticity.
Rugosity. When the medial thigh skin is excessively rugose and crepelike, liposuction may not provide satisfactory improvement. In older women and especially in women who have lost considerable weight, the skin overlying the anterior portion of the medial thigh tends to be rugose.
Liposuction will not improve this wrinkled appearance and even may worsen the degree of rugosity. Prospective patients whose anteromedial thighs already show some “crepiness” should be informed that liposuction may improve the shape while exacerbating the wrinkled appearance.
Surgical Options and Outcomes. Liposuction can significantly improve the shape of the medial thigh and create a smoother surface. The patient should see no unusual lumpiness, irregularity of shape, or visible evidence of a surgical procedure. The bulge of the medial thigh should be flattened so that the silhouette more closely approximates the contour of the musculature (Figure 34-8).
Women who find rugosity objectionable have the option of a medial thigh lift. In my experience, however, most patients are disappointed by the aesthetic results. They often cannot accept the scarring associated with medial thigh lift.
For patients with marked rugosity and minimal medial thigh fat, the most reasonable option may be no surgical treatment.
When drawing the topographic lines on the medial thigh, it is important to mark carefully the most proximal area to be infiltrated and suctioned. If the most proximal area along the sulcus between the thigh and the perineum is not well marked, it might be inadequately anesthetized and incompletely treated.
The diagonal course of the medial thigh furrow should be noted. The most prominent mounds of fat on the medial surface of the thigh and knee should be well designated by careful topographic markings before infiltration.
The subcutaneous fat of the medial thigh is susceptible to distortions that result from positions that deviate from the anatomic position.
The use of a Thigh Aside surgical positioning pillow helps place the targeted medial thigh in a position that approximates the anatomic position. The Thigh Aside is a rectangular foam pillow used for liposuction of the medial aspects of the thigh and knee. It supports the nontargeted leg in the high-step position and facilitates access to the entire length of the targeted medial thigh and knee in the anatomic position.
Other surgical positions used for medial thigh liposuction, such as the supine “frog-leg” position, tend to distort or warp the medial thigh fat and predispose to liposuction irregularities, such as lipowarp (Figure 34-9). With the patient in the anatomic position for medial thigh liposuction, subcutaneous fat is not unnecessarily stretched or distorted. Proper positioning minimizes the risk of inadvertent liposuction irregularities and improves patient comfort.
The lateral decubitus position does not always allow adequate access to all the medial thigh fat when it extends onto the proximal anterior thigh. In this situation, relatively small amount of liposuction is done with the patient lying supine and the thigh slightly spread apart (see Figure 34-7).
Because of the soft, minimally fibrous nature of medial thigh fat, an irregular infiltration may predispose to a lumpy liposuction result. To ensure homogeneous enlargement of the tumescent tissue, infiltration of the medial thigh must be done uniformly, which requires patience and thorough, deliberate technique. Attempting to complete the infiltration in the shortest time may decrease its accuracy and homogeneity.
Before the tumescent technique, liposuction was accomplished using large cannulas. Large cannulas created large tunnels. Because medial thigh fat is relatively mobile, it is readily deflected by a large cannula. Large cannulas would tend to reenter existing tunnels by following the path of least resistance. The result was an unintentional and undesirable enlargement of existing tunnels and uneven liposuction results (Figure 34-10).
With the tumescent technique and careful use of microcannulas, liposuction of the medial thigh should consistently yield smooth results (Figure 34-11). With tumescence the medial thigh fat is firm and immobile. Tumescence also produces profound hemostasis, which in turn permits the use of microcannulas.
Because microcannulas have a small cross-sectional area, they encounter minimal resistance when advanced through fat and thus can be accurately directed through the sessile fat, with minimal tendency to reenter preexisting tunnels. By producing a crisscross pattern of tunnels, microcannular liposuction of the medial thighs yields smooth, natural-looking results.
The adits or incisions on the medial thigh tend to be distributed along the diagonal medial thigh groove, along the posterior border of the medial thigh, and 2 to 4 cm from the anterior border of the medial thigh. The most important considerations when deciding where to place the adits are as follows:
- Convenient access to the targeted fat compartments
- Minimal visibility of the adits during the healing phase
- Optimal drainage of residual blood-tinged anesthetic solution
The initial phase of liposuction is accomplished using the smallest microcannulas, which are directed along the deepest planes of the subcutaneous fat. I prefer to use Capistrano microcannulas initially; however, a surgeon unaccustomed to these efficient cannulas should use a Finesse microcannula. Using a crisscross pattern, the surgeon directs microcannulas both proximally, from microincisions along the midportion of the medial thigh, and anteriorly, from adits along the posterior border.
On thin to average-size patients the entire medial thigh is typically treated using only 16-gauge and 14-gauge cannulas. A 12-gauge Capistrano cannula is used only for larger patients.
For patients who want a straight or vertical silhouette for the medial thigh, the last portion of the liposuction is accomplished using a 12-gauge Finesse cannula directed toward the area of the proximal medial thigh where the subcutaneous fat is the most prominent. The Finesse microcannula permits aggressive liposuction to be directed deeply while minimizing the risk of cannula injury to the overlying dermis.
To access the medial thigh fat that extends far onto the proximal anterior thigh, the patient is placed in a supine position with the thigh slightly spread apart. One incision or adit, placed at the proximal anterior margin of the medial thigh fat, is sufficient to treat this relatively small accumulation.
Postoperative care for the medial thighs or knees is simple and designed so that most patients can change dressings easily and without assistance. Recovery is rapid provided that (1) the surgeon has done some liposuction through an incision placed along the most dependent margin of the treated area and (2) this incision has not been sutured. Having thus guaranteed maximum drainage of the blood-tinged anesthetic solution, one need only apply adequate absorptive padding and moderately firm compression (see Chapter 30).
With multiple adits, drainage usually ceases within 36 to 48 hours. It is recommended that the garments be worn for an additional 24 hours after all drainage has ceased. Many women choose to wear the garments longer because of the comfort and security they provide (Figure 34-12).
Pitfalls and Special Considerations
The fat of the medial thigh is easily aspirated, so excessive liposuction can result without careful attention to proper surgical technique. Using microcannulas with multiple incisions and a pattern of crisscrossing diagonal and longitudinal cannula paths will minimize the risks of excessive liposuction (Figure 34-13).
The appearance of the medial thigh depends on the position of the underlying muscles. As a patient bends forward at the hip to view her own inner thigh, muscle contraction causes the midportion of the medial thigh to become more concave. When the patient stands erect, the subtle concavity disappears. Informing patients of this phenomenon before liposuction will avoid unnecessary worries and concern.
A male surgeon should always have a female assistant present during liposuction on the proximal medial thighs of a female patient.
When considering liposuction of the knee, the surgeon is principally concerned with the medial knee. The area that might be regarded as the anterior knee is more properly discussed with liposuction of the anterior thigh.
Gross Anatomy of Subcutaneous Fat. The fat of the medial knee is fairly well localized and devoid of significant fibrous tissue. The distal course of the greater saphenous vein courses superficially over the medial posterior thigh and passes over the posterior medial condyle of the femur. Several small veins and lymphatics pass longitudinally over the medial condyle. The muscles of the medial knee are the distal vastus, sartorius, adductor group, and semitendinosus.
Surface Anatomy. In some patients the medial thigh fat seems to extend onto the anterior thigh in a localized linear mound of tissue medial and proximal to the patella. The medial knee fat may extend proximally onto the thigh just anterior to the diagonal groove of the medial thigh. The medial fat can extend distally over the anterior tibia (Figure 34-14).
The fat pad of the medial knee is most prominent when the patient is standing erect in the anatomic position. When the knee is extended, the medial knee fat pad moves anteriorly and is displaced medially by the rounded ends of the tibia, known as the medial condyle. This medial displacement causes the overlying fat to bulge prominently.
When this fat pad is reduced in size by liposuction, the contour of the medial knee is more attractive and well proportioned. After liposuction, however, when the knee is bent at 90 degrees, the medial knee may appear to have a slight concavity. This indentation is not unattractive, but a patient should be forewarned of this predictable consequence of liposuction.
The knee and the distal anterior thigh are often the focus of patient concerns. Liposuction can greatly improve the medial knee. With liposuction of the suprapatellar thigh, however, the degree of improvement is limited.
When the patient expresses concern about “the knee” during the initial consultation, the surgeon must be careful to determine the exact areas of concern. Using a ball-point pen to draw on the patient’s skin, the surgeon can show the patient the extent of the proposed liposuction. This prevents misconceptions and clarifies communication between the surgeon and patient.
Most of the medial knee fat is located within an oval-shaped area overlying the medial condyle. Drawing two or three concentric ovals usually suffices to designate the medial knee fat.
The adits at the distal extent of the knee should be placed 1 or 2 cm distal to the target mound of subcutaneous fat. Thus the area designated for infiltration should extend more distally than the area to be suctioned.
The subcutaneous fat of the knee is susceptible to distortions when the knee is bent. This distortion is eliminated when the operative position approximates the anatomic position. When the patient’s knee is bent, for example, the medial fat pads move posteriorly and seem to disappear behind the medial condyle.
A modified lateral decubitus position for the medial knee generally suffices when the medial thigh is not being treated. By moving the uppermost contralateral leg anteriorly, the target medial knee is accessible in the anatomic position.
When the medial thigh and knee are treated simultaneously, the Thigh Aside pillow is recommended to help position the patient and provide optimal access to the targeted fat.
The knee is a sensitive area. In a fully awake and alert patient the infiltration of the medial knee must be done gently. The initial infiltration using a pediatric spinal needle, followed by a 20-gauge spinal needle, is generally well tolerated.
The medial knee is a small compartment and may become tumescent before the anesthetic solution has been infiltrated into the entire knee. Thus the infiltration should be done deliberately rather than as rapidly as possible.
Microcannular tumescent liposuction of the medial knee consistently produces excellent results and rapid recovery (Figure 34-15).
The medial knee requires three to eight adits or incisions. A distal dependent incision or adit on the medial knee ensures adequate drainage. With liposuction by local anesthesia, medial knees are particularly sensitive; the smaller the cannula, the less the likelihood of pain and discomfort.
Knee liposuction is initiated using 16-gauge Capistrano microcannulas and is completed with a 14-gauge Capistrano cannula. Occasionally a 12-gauge Finesse microcannula is used. For knee liposuction the cannula is generally directed longitudinally rather than transversely, to minimize the risk of interrupting blood and lymphatic vessels.
Medial knee adit sites heal with minimal scarring and hyperpigmentation. The surgeon must avoid excessive superficial liposuction to prevent injury to the dermal vascular plexus and lymphatics.
Postoperative care for the medial knee is similar to that for the medial thigh (see earlier discussion).
When the medial thighs and medial knees have been treated concurrently, and especially when the patient is somewhat obese, drainage may persist for several days. It is recommended that the garments be worn for 24 hours after all drainage has ceased.
Pitfalls and Special Considerations
The goal of medial knee liposuction is to achieve a smooth result that is natural in appearance. The goal should not be to extract as much fat as possible. Overaggressive superficial liposuction of the medial knee can injure the lymphatic vessels that pass immediately beneath the dermis and deeply over the medial condyle. Injury to these lymphatics can produce either (1) an incision site with prolonged drainage of yellow serosanguineous fluid or (2) a seroma.
Aggressive liposuction also can injure the dermal vascular plexus, causing erythema ab liporaspiration with hyperpigmentation and a persistent, mottled, reticulated vascular pattern.
The gross anatomy of the subcutaneous fat of the anterior thigh is rather homogeneous. The fibrous stroma is easily penetrated with minimal resistance. The subcutaneous fat at the proximal extent of the anterior thigh is usually thicker than the distal portion. Prominent bulges of fat can extend from the lateral thigh or from the medial thigh onto the proximal anterior thigh.
Such areas require relatively more liposuction to achieve a uniformly smooth and attractive result. Careful contour drawings of the subcutaneous fat are important for accurate tumescent liposuction of the anterior thighs (Figure 34-16).
In the preferred intraoperative position for liposuction of the anterior thighs, the patient is supine with the knees supported and slightly elevated with a small pillow or folded towel. Infiltration follows the same principles as for infiltration of the medial thigh/knee.
Surgical technique for liposuction of the anterior thigh focuses on avoiding any superficial liposuction. The goal is to work in the deeper planes, leaving a smooth, relatively thick layer of superficial fat. Typically the entire liposuction of the anterior thigh is suctioned using only a 16-gauge Capistrano microcannula and 14-gauge Capistrano cannulas, 15 cm (6 inches) and 23 cm (9 inches) in length.
The cannulas are principally directed parallel to the long axis of the thigh. Crisscrossing of tunnels occurs with small angles of intersection. For smooth results it is important not to direct the 14-gauge cannula paths transversely across the thigh. Since using 16-gauge microcannulas carries minimal risk of creating lipotrops, the surgeon can make transverse tunnels.
Pitfalls and Special Considerations
On the anterior thighs, optimally smooth results are more important than maximal volume reduction. The anterior thighs are one of the areas most susceptible to postliposuction irregularities of the skin.
Removing more than 50% to 60% of the subcutaneous fat of the anterior thigh is associated with a high incidence of patient dissatisfaction. The fat has minimal fibrous content and therefore is aspirated rather quickly. Even with microcannulas it is difficult to achieve smooth results consistently when removing more than 60% of the fat from the anterior thigh.
The surgeon must also avoid complying with patients’ requests to “take just a little more” from the area proximal to the patella. This is a common pitfall. Too often the ultimate result is a “scooped-out” appearance and a dissatisfied patient. To treat the anterior knee adequately, the surgeon usually must taper the degree of liposuction proximally over most, if not all, of the anterior thigh.
The fat immediately superficial to and surrounding the patella is more fibrous than the fat of the distal thigh. Using a 16-gauge microcannula to initiate liposuction in the peripatellar fat helps achieve smooth results.
Circumferential Thigh Liposuction
Circumferential liposuction of the thighs is most easily tolerated by the patient if it is accomplished as a serial procedure. Liposuction of the anterior thigh can be accomplished together with either the lateral thigh or the medial thigh/knee. Liposuction of the entire thigh circumference during one day is not recommended. Although the risk is small, liposuction of the entire thigh circumference may predispose to deep venous thrombosis and pulmonary thromboembolism because of distal swelling with venous stasis and subsequent postoperative immobility.
Patients may want their entire thighs treated during one session, assuming that one surgery and one recovery will be easier and preferable to two procedures. Because of safety concerns, I refuse to perform circumferential liposuction of the thighs during only one session.
In fact, circumferential liposuction accomplished by one surgical procedure will result in prolonged distal edema, more discomfort, and delayed return to normal activities. By avoiding circumferential thigh liposuction that is completed during a single procedure, the surgeon also avoids time-consuming postoperative visits and telephone calls from anxious patients.
Serial surgeries are preferred, with the sessions spaced 1 month or more apart. For example, the surgeon might treat the outer thighs, hips, and buttocks during one session, then the anterior thighs, medial thighs, and knees in the next session. This approach virtually eliminates distal lower extremity edema. Typically, patients can be expected to return to work 1 or 2 days after surgery.
Liposuction transects many lymphatics. When the entire thigh is treated, it remains swollen for a long time. Immediate circumferential liposuction causes lymphostasis, with delayed clearing of postoperative transudates and inflammatory exudates. The resultant osmotic pressure within the subcutaneous fat causes prolonged tissue edema.
Dividing circumferential liposuction into two separate procedures reduces total days of postoperative disability. The untreated portion of the thigh provides functioning lymphatics that compensate for the impaired lymphatic drainage in the treated area.
Similarly, sequential thigh liposuction reduces the degree of edema-induced venous stasis and the risk of thromboembolic venous disease.
Figure 34-1 Topographic contour mappings designate location and depth of fat on medial thigh and medial knee. A, Basic outline of fat compartments. B, Detailed contour mapping of medial thigh plus orthogonal grid pattern to facilitate tumescent infiltration.
Figure 34-2 Medial thigh furrow (wide line) is surface depression extending from proximal anterior to distal posterior thigh. Furrow divides area into medial thigh (proximal) and medial knee (distal).
Figure 34-3 Full view of medial thigh/knee contour drawings. A, Right medial thigh, with patient standing and raising left thigh. This view demonstrates medial thigh furrow. B, Left medial thigh, with patient standing and raising right thigh. C, Left medial thigh approximately in anatomic position, with patient lying on left side and right thigh resting on Thigh Aside pillow.
Figure 34-4 Medial thigh/knee position for liposuction of inner thigh and knee is modified lateral decubitus with uppermost hip flexed in high-step position and ipsilateral leg resting on Thigh Aside, a brick-shaped 58 × 23 × 15–cm (23 × 9 × 6–inch) surgical positioning pillow. By placing targeted inner thigh and inner knee in approximated anatomic position, inadvertent liposuction-induced irregularity of skin is less likely. Before positioning patient, Thigh Aside is placed inside sterilized, single-use plastic bag, which in turn is covered by a sterile superabsorptive operating room sheet (see also Figure 40-5).
Figure 34-5 Posterior extension of medial thigh fat pad, even when disproportionately large, is easily accessible from lateral decubitus/high-step position. When inner thighs are treated with patient in supine position, posterior extent of inner thigh cannot be adequately accessed or treated. Contour lines are drawn on left side; only the outline is drawn on right side.
Figure 34-6 Proximal anterior extension of medial thigh fat compartment may become more prominent with increasing obesity.
Figure 34-7 Anterior extension of medial thigh fat compartment may not be accessible from lateral decubitus position and may require liposuction in