Approaches to the Hip: Minimally Invasive Direct Anterior Total Hip Arthroplasty on Standard Operative Table
Total hip arthroplasty (THA) can be safely performed via various surgical approaches. The classic direct anterior approach to the hip was first described by Smith-Peterson. Currently, the most commonly used anterior approach is the Hueter approach. This approach uses the distal two-thirds of the incision used for the classic approach and does not require detachment of the tensor fasciae lata from the anterolateral iliac crest, sectioning of the reflected head of the rectus, or release of the piriformis. Theoretically, the direct anterior approach allows surgeons to perform minimally invasive THA via an intermuscular plane without detaching muscle from bone. However, the Hueter approach is associated with a high rate of lateral femorocutaneous nerve (LFN) damage. Therefore, a modified Hueter approach that uses a more lateral incision has been developed to decrease the risk of LFN damage. The minimally invasive anterior approach for THA is safe and effective, resulting in early postoperative improvements in pain and function. Although a specific surgical table is not necessary for the procedure, dedicated instruments help reduce the risk of acetabular component malpositioning and greater trochanter fracture.
This video demonstrates the technique for THA via the minimally invasive direct anterior approach. More than 500 procedures were performed between 2012 and 2014 in the department of the authors of this video.
The case study presented in this video is that of a 67-year old woman with right hip pain that developed and worsened in the past 3 years. The patient presented with hip pain and a limp and was able to walk with the use of a cane and perform limited daily activity. Her body mass index was 24.3 kg/m2. The patient's preoperative evaluation included a complete blood workup, a Harris hip score of 59.4, and standard radiographs that revealed right hip osteoarthritis with slight acetabular dysplasia. THA via the minimally invasive anterior approach was performed using a standard surgical table with both legs included in the surgical field to guarantee correct exposition of the femoral canal. Instruments with specific offset were used to prepare the acetabulum and femur for the implant. Given the patient's slight acetabular dysplasia, the prosthetic acetabulum was stabilized with the use of two screws. The patient did not require transfusions and was able to walk 1 day postoperatively.
The minimally invasive anterior approach for THA is a useful and safe approach that decreases immediate postoperative pain and bleeding and allows for prompt rehabilitation. Major disadvantages of traditional anterior approaches for THA are a high rate of LFN damage; difficult visualization of the femur with a high rate of femoral fracture; and difficult orientation of the acetabular component, which frequently is implanted in an excessively vertical position. An incision 2 cm distal and 2 cm lateral the anterior superior iliac spine in the direction of the lateral epicondyle of the distal femur that is extended 6 to 8 cm is suggested to access the anteromedial portion of the tensor fasciae lata. The muscle fascia is incised and detached from the muscle fibers superiorly and medially to access the intermuscular space without damaging the LFN. Dedicated instruments are mandatory for correct exposure of the acetabulum and the femur. Dedicated reamers and femoral broaches with offset decrease the incidence of complications, such as cup malpositioning and femoral fractures.
The minimally invasive anterior approach for THA affords good access to the acetabulum and femur with preservation of the hip muscular attachments; improves control of acetabular cup positioning and leg lengths; does not require hip dislocation; and is associated with low blood loss, a short hospital stay, and few complications.