The patient selected for anterior surgery should be evaluated to ascertain that the hip can be adequately reconstructed anteriorly and that there will be no

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Over 1 million times per year, Biomet helps one surgeon provide personalized care to one patient. The science and art of medical care is to provide the right solution for each individual patient. This requires clinical mastery, a human connection between the surgeon and the patient, and the right tools for each situation. At Biomet, we strive to view our work through the eyes of one surgeon and one patient. We treat every solution we provide as if it™s meant for a family member. Our approach to innovation creates real solutions that assist each surgeon in the delivery of durable personalized care to each patient, whether that solution requires a minimally invasive surgical technique, advanced biomaterials or a patient-matched implant. When one surgeon connects with one patient to provide personalized care, the promise of medicine is ful˜lled. One Surgeon. One Patient.®

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1Anterior Supine Intermuscular THAThis brochure describes the surgical technique and postoperative care protocol used by Erik De Witte, M.D.; Roger H. Emerson, Jr., M.D.; Edward J. Stolarski, M.D.; Michael Pretterklieber, M.D.; W. Vincent Burke, M.D.; Hari P. Bezwada, M.D. and Michael A. Wilmink, M.D. Biomet does not practice medicine and does not recommend this or any other surgical technique for use on a specific patient. The surgeon who performs any implant procedure is responsible for determining and using the appropriate implants and techniques for implanting the prosthesis in each individual patient. This technique can be conducted with various femoral stems. Figure 1 Surgical PlanningThe patient selected for anterior surgery should be evaluated to ascertain that the hip can be adequately reconstructed anteriorly and that there will be no need to augment the posterior acetabulum. The skin on the front of the hip must be normal in appearance without any maceration.The radiographs should be templated to suggest the likely implant size and orientation. The level of the hip center and position of the femoral osteotomy from the tip of the greater trochanter or lesser trochanter should be determined.Note: The Anterior Supine Intermuscular (ASI) surgical technique may be performed on a standard operating room (OR) table or special fracture table. The following technique is for use with a standard OR table. Patient PositioningPosition the patient supine (Figure 1) on a ˜uoroscopy capable table, with the ˜uoroscopy machine in the room. the level of the break in the table. This will permit appropriate motion of the femur as the table is extended. and the hip must be positioned to permit ˜uoroscopy views of both hips and the obturator foramen. with the hip radiographs for later reference.

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2Patient Preparation Prepare both legs and drape each free to permit crossing the operative leg underneath the nonoperative side. The entire iliac crest should be included in the operative ˚eld to permit an extensile exposure if needed. The nonoperative leg should be prepped from the toes to the groin, and then draped to permit full movement of the leg. The draping could be either with stockingette material alone or in combination with adhesive plastic draping for a more secure seal. Ipsilateral side is prepped from the midline above the ASIS to mid-thigh. in case of the need to use a counter incision in the buttock. This is rarely required but may be needed to pass a reamer into the femoral canal. Figure 2 Skin IncisionThe anterior supine incision is the distal portion of the Smith-Petersen approach. The incision is determined using the ASIS as a reference. Measure two ˚nger-widths below and two ˚nger-widths lateral to the ASIS (Figure 2). The incision is centered over the greater trochanter. The incision should be well lateral to the Tensor-Sartorious interval to stay away from ˚bers of the lateral femoral cutaneous nerve. The incision is over the muscle belly of the Tensor and should follow the course of the muscle distally. Therefore, the incision will be approximately 30° away from the midline of the ASIS. Longer skin incisions do not increase the amount of muscle dissection and the skin incision length should always be adequate for safe visualization of the surgical structures.

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3Figure 3 An oblique incision is made slightly lateral to the intermuscular space between the Tensor Fasciae Latae (TFL) on the lateral side and the Sartorius on the medial side (Figure 3). The incision is centered over the greater trochanter. estimated cup diameter. In obese patients, the incision is made more laterally. Smith-Petersen approach coming up and around the iliac crest or going distally across the TFL and then under the Vastus Lateralis to the knee. Subcutaneous Tissue At this location, the subcutaneous tissue is usually thin, even in obese patients. However, as in the anterolateral abdominal wall, the subcutaneous tissue on the anterolateral aspect of the thigh consists of two layers: a a deeper ˚brous layer (Scarpa™s fascia). This membranous area strengthens the otherwise unstable fatty tissue. Between the Scarpa™s fascia and the tensor muscle fascia on the thigh covering the underlying muscles, a small amount of fatty tissue is interposed. It is that layer in which the lateral femoral cutaneous nerve courses downwards through the operative ˚eld. Dissect the plane until the tensor muscle fascia is reached. Sharply incise the tensor muscle fascia in the same direction as the subcutaneous tissue, but slightly longer than the skin incision to facilitate a fimoving windowfl. Normally you will not see ˚bers of the lateral femoral cutaneous nerve. If the nerve is encountered, move the facial dissection more laterally to protect the nerve. SartoriusTensor Fasciae Latae

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4Muscular DissectionAfter incising the tensor muscle facia, lift up the medial fascial edge and then, by blunt ˚nger dissection under the fascia, develop the interval between the TFL and the Sartorius. Extend this interval down to the hip joint (Figure 4). The intermuscular space can be easily developed by ˚nger pressureŠonly in a medial directionŠuntil the capsule can be palpated. This preparation should be completed without force in order not to damage the ascending branch of the lateral circum˜ex femoral artery and its accompanying vein within the operative ˚eld. The circum˜ex vessels are over the intertrochanteric line and run between the gluteus medius and rectus femorus. They are usually in the middle of the incision or slightly inferior. Blood loss will be greatly decreased if you identify and cauterize or ligate these vessels (Figure 5). Figure 4 Figure 5

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6Figure 8 To prepare for exposing the anterior capsule, place a 6superior to the lateral capsule or against the ilium to retract the abductors. Place a second retractor, a large sharp Hohmann 7inferior to the femoral neck. Place third retractor 9under the rectus tendon, but on top of the anterior acetabular rim in the upper cranial quarter directed to the opposite shoulder to avoid injury to the femoral nerve and vessels (Figure 8). Identify the re˜ected head of the rectus and release to allow the long head of the rectus to retract medially. Beware of capsular bleeding at the inferior-medial capsule. capsulectomy results in excellent visualization and aids in femoral mobilization (Figure 9). Make sure to release the anterior-superior capsule from its insertion in the piriformis fossa in order to facilitate lifting of the femur. Place the first two retractors 6and 7inside the capsule for protection when the osteotomy is performed (Figure 9 ).Figure 9 997766

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7Figure 11 After removing the head and neck piece, the assistant can externally rotate the leg and the surgeon can palpate the lesser trochanter to further guide the level of the ˚nal neck resection. Some anterior capsule may need to be released from the femur to facilitate this maneuver. Beware of damaging the TFL muscle when removing the neck and head.Note: When removing the head, it may be easier to place the corkscrew prior to cutting the neck. Additionally, retraction of the leg at the ankle will aid in the removal of the femoral head.Note: If necessary, an additional and ˚nal neck cut should be carried out at this time in order to provide as large an opening as possible for reaming the acetabulum. If there is be utilized to help determine the exact level of osteotomy. Osteotomy of the FemurPerform an osteotomy at the cartilage/neck junction (Figure 10). It may be necessary to perform two separate parallel cuts to facilitate extraction of the femoral head by ˚rst removing the wafer of cut bone. The initial osteotomy should be at the head/neck junction. The second should be 5 mm to 1cm distal to the initial osteotomy. The segment of bone can be removed with a tenaculum or threaded Steinman to help determine the exact level of the osteotomy as planned from preoperative templating. Place a corkscrew through the cortical side of the femoral head and spin the head to rupture the ligamentum. This will aid with dislocation (Figure 11). The ligamentum cutter (Figure 11) may be used to aid in the cutting of the ligamentum.Figure 10 976976

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8Figure 13 Exposure of the Acetabulum After exposing the borders of the acetabulum, place the following three retractors (Figure 13): 1. Place retractor 9on the anterior aspect of the acetabulum, as shown above. 2. Place a double-pronged (Mueller type) retractor 8, on the posterior border of the acetabulum. Downward pressure on this retractor should bring the femur posterior, providing excellent acetabular visualization. A small incision may need to be made in the posterior capsule. 6on the inferior side of the acetabulum, behind the transverse acetabular ligament.Figure 12 Be careful to protect the tensor and rectus muscles to avoid muscle damage. Use of atraumatic reamers are available and make passing the reamers in and out of the incision easier. Note: Removing femoral bone to the desired osteotomy level determined by templating should be done before acetabular reaming to facilitate passing of the reamers into the acetabulum. Some gentle longitudinal traction and/or rotation of the femur will also allow easier insertion and removal of the reamer heads. 9688

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9Reaming the AcetabulumRemove any central osteophytes with an osteotome to help prevent small reamers from slipping anteriorly or posteriorly. The true acetabular ˜oor is now exposed and reaming can be started. Start reaming horizontally until you reach the true ˜oor and then go progressively to 45° lateral inclination and 15° to 20° of anteversion (Figure 14). Figure 14 Note: The tendency is to ream more anterior due to eccentric reaming with ˚nger palpation between reamer sizes. Reaming should be performed under direct vision only. Beware of reaming too far medially from the anterior position.968

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