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electrocautery, centered over the trochanter. The distal aspect of the
gluteus maximus is then split (Fig. 5.2). Self-retaining retractors can be positioned
to maintain exposure. The inferior border of the gluteus medius is identified. The decision is then made on how
much muscle to reflect. A blunt elevator is used to define a recess of the gluteus medius muscle in line with its
fibers. This maneuver separates the anterior 10% to 30% of the gluteus medius muscle and exposes the gluteus
minimus tendon (Fig. 5.3). Less gluteus medius tendon can be reflected in thinner patients and as experience
with the technique grows. Electrocautery is used to release the anterior portion of the gluteus medius off the
anterior aspect of the greater trochanter (Figs. 5.4 and 5.5). There is usually a vascular bundle in this tissue.
Retractors are placed to help visualize the gluteus minimus tendon, with its fibers oriented obliquely to the
gluteus medius as well as the anterior hip capsule.
Figure 5.2. Following skin and fascial incisions, the distal aspect of the gluteus maximus is split. (Reprinted from
Freiberg AA. Anterolateral mini-incision total hip arthroplasty. Operative Techniques in Orthopaedics.
2006;16(2):87–92, with permission.)
Figure 5.3. The anterior-inferior border of the gluteus medius is identified (marked with a hemostat). The
superior mark identifies the anterior aspect of the trochanter, defining approximately 30% of the gluteus medius
tendon. The electrocautery mark is where the medius split will be. (Reprinted from Freiberg AA. Anterolateral
mini-incision total hip arthroplasty. Operative Techniques in Orthopaedics. 2006;16(2):87–92, with permission.)
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Figure 5.4. The anterior border of the gluteus medius is marked and then released off the anterior aspect of the
greater trochanter. (Reprinted from Freiberg AA. Anterolateral mini-incision total hip arthroplasty. Operative
Techniques in Orthopaedics. 2006;16(2):87–92, with permission.)
Figure 5.5. Illustration of deep exposure. (Redrawn from Freiberg AA. Anterolateral mini-incision total hip
arthroplasty. Operative Techniques in Orthopaedics. 2006;16(2):87–92, with permission.)
Using a long-tipped electrocautery device, an incision is then made through the gluteus minimus tendon in line
with the femoral neck. Retractors can be placed inside the minimus incision. Then incise the anterior hip capsule
centered on the middle of the femoral neck (Fig. 5.6), starting proximally at the anterior labrum just superior to
the gluteus minimus tendon and continuing laterally toward the greater trochanter. Then the leg is slightly
externally rotated as the incision is carried inferiorly along the anterior aspect of the proximal femur through the
gluteus minimus and anterior gluteus medius tendons. Finally the incision is taken medially along the inferior
border of the gluteus medius muscle to create a thick U-shaped flap for future closure. The gluteus medius flap is
tagged with a
suture to facilitate exposure of the hip capsule and to aid in identification for closure. Retractors are placed
superior and inferior to expose the femoral neck. In addition, a retractor can be gently placed on the anterior lip
of the acetabulum to improve visualization.
Figure 5.6. Retractors placed inside gluteus minimus incision. The direction of the capsular incision is marked.
(Reprinted from Freiberg AA. Anterolateral mini-incision total hip arthroplasty. Operative Techniques in
Orthopaedics. 2006;16(2):87–92, with permission.)
The capsule is kept on stretch with the leg in an extended and externally rotated position and the remaining
anterior capsule is removed (Fig. 5.7). There is often a substantial band of inferior capsule that needs to be
incised to allow atraumatic anterior dislocation of the hip. In a similar manner, impinging anterior osteophytes
must also be removed before attempting hip dislocation. To approximate leg length, a tagging suture is placed in
the skin proximal to the incision and cut at the level of a reproducible mark placed on the vastus ridge prior to
dislocation. The leg is then extended and externally rotated with traction, and the hip is gently dislocated. The
femoral neck is exposed until the lesser trochanter is easily palpated. Careful preoperative templating and
intraoperative assessment will help to determine the level of the neck cut. A cutting guide can also be utilized to
aid in proper orientation of the neck cut. A femoral neck osteotomy is then performed, with care taken not to
damage the greater trochanter. The femoral head and neck are removed, and the acetabulum is exposed.
Figure 5.7. Femoral head and neck exposure following capsulotomy and external rotation of the limb. (Reprinted
from Freiberg AA. Anterolateral Mini-incision total hip arthroplasty. Operative Techniques in Orthopaedics.
2006;16(2):87–92, with permission.)
Acetabular retractors are positioned around the rim of the acetabulum with the leg in neutral position on the
table. The posterior retractor serves to retract the proximal femoral shaft. Anterosuperior and anteroinferior
retractors serve to protect the anterior gluteus flap and iliopsoas tendons, respectively. The remaining anterior
hip capsule can be safely removed medially until the iliopsoas tendon is encountered. Then the residual capsule,
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labrum, osteophytes, and pulvinar are debrided to expose the bony acetabulum. Care should be taken to define
the anterior and posterior wall of the acetabulum as well as the medial teardrop.
Low-profile reamers can be used to prepare the acetabulum. There are a variety of reamer shapes that have
been designed to allow easier insertion into a smaller wound. Reaming is initiated with the largest acetabular
reamer that will “bottom out” the acetabulum, as demonstrated by medial teardrop. It is important to position the
reamer in the desired orientation of the acetabular component. Also, with a smaller incision, it is important to
ensure that reamer and component orientation are not compromised by the surrounding structures. Small
movement of the leg can significantly improve bone exposure. The acetabulum is progressively reamed until the
optimal cup size is reached and punctate bleeding of the subchondral bone is noted.
The acetabular component is then inserted with the desired cup orientation depending on anatomic features,
usually 40 to 45 degrees of abduction and 10 to 20 degrees of anteversion. Anteversion can also be safely
increased with the use of a larger hip articulation (39). An alignment guide can be attached to the insertion
device to aid in component positioning. Proper seating, orientation, and stability of the component are carefully
assessed. Screws can be inserted for added stability if desired. The bearing surface is impacted.
The operative leg is flexed, externally rotated, and adducted. A femoral neck elevator is inserted. In addition, an
anterior retractor can be placed (Fig. 5.8). This allows for maximal femoral elevation and exposure. Placing the
leg in the anterior leg bag and hyperrotating the leg facilitates broaching and stem placement (Fig. 5.9). A box
osteotome or rongeur is used to begin preparation of the proximal femur. Particular attention should be paid to
ensure a lateral starting point and proper femoral anteversion. A tapered starting awl is then gently passed into
the femoral shaft in a coaxial manner. A blunt-tipped side-cutting reamer can be used to achieve optimal
lateralization. If required, intramedullary reamers are passed to sequentially ream the canal. Otherwise,
sequential broaching is then initiated until good filling of the proximal and/or distal canal is noted, depending on
stem design. To help guide correct component anteversion, an alignment tool can be attached to the broach
handle. As a general rule, the ability to sink the broach, more than 5 mm below the femoral
neck cut indicates