sixty four - year - old female presented to our hospital with a history of left hip pain with limping gait .
her hip pain and limping gait were started about 2 years ago and 5 months ago , respectively .
she had no special trauma history and discomfort on her hip joint until two years ago .
plain radiographs on pelvis including anteroposterior and frog leg lateral view were taken initially ( fig .
lateral center edge angle , acetabular inclination , and femoral head extrusion index were 5 , 30 , 41.6% respectively .
since the use of pain killer for several months was not helpful for her pain , the patient wanted a surgical treatment , so was elected to undergo total hip arthroplasty . during the operation , the patient was placed in right lateral decubitus position and the surgical approach was posterolateral .
after skin incision , gluteus maximus was split as a usual manner . after cutting the short external rotator and the joint capsule , the joint was dislocated and neck was cut .
2 ) . fatty change of gluteus medius and minimus and tensor fascia latae were detected on preoperative computed tomography scan ( fig .
, one can see the bulk gluteus medius at the tip of the greater trochanter .
the operation was carried out and all trial implants were inserted in the acetabulum and femur .
however the stability was disappointing because the dislocation was happen at the 70 flexion and neutral rotation .
we decided to transfer of anterior fiber of gluteus maximus to reconstruct the abductor deficiency at the hip joint .
we harvested the gluteus maximus with a length of 12 cm from the 4 cm distal at the tip of the greater trochanter .
the width of the harvested muscle was 3 cm at the distal end but the width was gradually increased as going to the proximal portion like fan .
nonabsorbable suture material was applied with krackow suture technique on the distal end of the harvested muscle .
we made a hole with the size of 13 cm to pass through the muscle at the 2 cm distal to the tip of the greater trochanter ( fig .
the harvested muscle was passed through the hole from medial to lateral and securely sutured through the bone tunnel which is located 3 cm distal to the hole in 20 abduction ( fig .
however , we could n't find the exact cause of the neuropathy . during the rehabilitation period ,
after then gradual strengthening exercise and weight bearing was permitted . at two years of follow up , the patient showed a slightly positive trendelenburg sign with mild limp .
well known causes of this unique condition include rupture of the abductor tendon at its insertion , failure of repair of abductor during the total hip replacement , multiple revision total hip replacement and injury of superior gluteal nerve which innervates hip abductors234 ) . in current study
, there was no readily identifiable cause for superior gluteal nerve injury such as trauma , injection around hip joint , prior surgical history .
fehm et al.6 ) reported the results of repair of a deficient abductor mechanism with achilles tendon allograft .
kohl et al.7 ) introduced vastus lateralis muscle shift technique and had showed the satisfactory result . as they mentioned in the article , however , their technique is complex , demanding , relatively high complication rate and not easily applicable by many surgeons .
an anatomic study1 ) showed the gluteus medius is composed of three distinct parts making up the fan shape .
the posterior part of this muscle and gluteus minimus run almost parallel to the neck of the femur .
distal attachments of these two muscles are the anterosuperior margin of the greater trochanter not the lateral aspect . in this study , also , the authors postulated that the gluteus medius and minimus function primarily as hip stabilizers and pelvic rotators , rather than hip abductors .
in other words , the horizontal fibers work as hip stabilizer and the vertical fiber is pelvic rotator .
the primary function of hip abduction would then be achieved via the tensor fasciae latae muscle . according to this study
, the joint stability can be achieved by transfer of the anterior fiber of gluteus maximus which have a running route similar to horizontal fibers of gluteus medius and gluteus minimus .
if the function of the tensor fascia latae is normal , transfer of this muscle is n't necessary .
one is transfer of anterior fiber of gluteus maximus and the other is combined transfer of gluteus maximus and tensor fascia latae .
the concept of whiteside 's techniques is similar with our technique ; however , the differences are as follow .
we thought this method would reconstruct the gluteus medius and minimus simultaneously and may stabilize the femoral head in the acetabulum more effectively due to its closer location from the joint .
the second one is posterior capsule enforcement with posterior fiber of gluteus maximus . theoretically , it would be better than no soft tissue envelop in terms of preventing dislocation .
but we ca n't make sure the effectiveness in the artificial joint . because many hip surgeons experiences that dislocation does n't happen in the artificial joint without posterior capsule .
the correct position of the implant , reconstruction of the deficient abductor and patient education are the cornerstone to prevent the dislocation .
however , it 's impossible to transfer this muscle because combined deficiency with gluteus medius due to superior gluteal neuropathy .
we think current technique is one of the useful treatment methods to gain joint stability and abductor function in the abductor deficient hip joint .
 abductor deficiency in native hip joint may cause severe limping and pain . 
 it is more serious situation in case of arthroplasty due to instability and recurrent dislocation . 
 well - known causes of abductor deficiency are repeated surgery , chronic trochanteric bursitis , superior gluteal nerve injury , failure of repair of abductor tendon insertion to the greater trochanter . 
 author had experienced primary abductor deficiency during total hip replacement and treated successfully with the transfer of gluteus maximus . 
 we 'd like to introduce the operation technique with the review of literature . 
CASE REPORT
DISCUSSION