Indications

• Primary hip arthroplasty

• Revision hip arthroplasty

  Treatment Options

  • Lateral approach

  • Anterolateral approach

  • Anterior approach

   

  Examination/Imaging

• Anteroposterior/lateral radiographs of pelvis

  Surgical Anatomy

• The gluteus maximus is split in the line of fibers; its proximal segmental nerve supply prevents significant dennervation (Fig. 1A).

• Short rotators (piriformis, obturator internus and superior/inferior gemelli) are taken down, exposing the entire posterior capsule (Fig. 1B).

• The sciatic nerve is protected by the bulk of the short rotators, which lie between the nerve and the posterior retractor.

• To increase exposure, the quadratus femoris and gluteus major insertion into the gluteal tuberosity on the femur can be divided, leaving residual soft tissue stumps attached to the femur for repair.

• Capsulotomy along the base of the femoral neck allows easy dislocation of the hip joint and good visualization of the femur and acetabulum (Fig. 1C).

   

  A

   

   

  FIGURE 1

   

  Posterior Approach to the Hip

   

   

   

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  FIGURE 1, cont’d

   

  •  

   

  Posterior Approach to the Hip

   

  Positioning

• The patient is placed in the lateral decubitus position (Fig. 2).

• The pelvis is secured with anterior/posterior bolsters resting on the pubis/sacrum.

• The trunk is secured with anterior/posterior bolsters at the sternum/scapulae.

• An axillary bump is used to decrease pressure on the inferior arm.

  Portals/Exposures

• With the surgeon standing behind the patient:

  • Make a longitudinal skin incision with a posterior curve proximally toward the posterior superior iliac spine (Fig. 3).

    • Center over posterior third of greater trochanter.

    • Expose fascia lata/gluteus maximus fascia.

  • Incise the fascia and split the gluteus maximus in the line of the skin incision (Fig. 4).

     

     

     

     

    FIGURE 2

     

     

     

     

     

    Posterior Approach to the Hip

     

     

     

    73

     

    FIGURE 3

     

    FIGURE 4

     

     

     

     

    74

     

     

    P EARLS

    • With the hip flexed to 45°, the incision is a straight line, in line with the axis of the femur.

       

    • Internal rotation of the hip tightens the short rotators, allowing division close to the insertion.

       

    • Dividing the piriformis as close to the femoral insertion as possible will still leave a residual stump in the piriform fossa for capsular repair.

       

    • Incise the capsule as one full-thickness layer. If there is a large posterior osteophyte, try to dissect the capsule off to facilitate closure.

       

    • Posterior osteophytes may prevent easy dislocation and should then be removed with a chisel to facilitate dislocation of the hip without undue rotational force on the femur.

       

    • If dividing the quadratus femoris for increased exposure, be aware that medial circumflex femoral artery branches are close to its femoral insertion, so divide the muscle slowly with cautery.

     

    Posterior Approach to the Hip

     

    FIGURE 5

     

  • Incise the trochanteric bursa to expose the gluteus medius and short rotators (Fig. 5).

  • Internally rotate the femur to put the short rotators under tension.

  • Place a retractor deep to the gluteus medius and gently retract the muscle (Fig. 6A).

  • Identify the piriformis tendon (white cordlike structure) under the posterior edge of the gluteus minimus. The obturator internus and gemelli insert distal to this as a conjoined tendon (Fig. 6B).

  • The sciatic nerve lies within yellow fat, usually appearing under the inferior border of the piriformis muscle. We do not expose this nerve.

     

     

     

    75

     

     

    P ITFALLS

    • Avoid posterior fascial incision as the gluteus maximus insertion into the iliotibial band will obscure correct placement.

       

    • Splint the gluteus maximus fibers gently to avoid excessive bleeding.

       

    • Ensure that the retractor deep to the gluteus medius is superficial to the piriformis tendon; if you can’t see the tendon, reposition this retractor (see Fig. 6A)!

       

    • Maintain the length of the piriformis, otherwise it will be too short to repair.

       

    • Feel and listen when impacting the Steinmann pin to ensure that it goes through both tables of the ilium, so it doesn’t loosen and move during the operation.

       

    • Avoid excessive posterior retraction to prevent injury to the sciatic nerve.

     

    Posterior Approach to the Hip

     

    A

     

     

     

    B

    FIGURE 6

     

     

    76

     

     

     

    Posterior Approach to the Hip

     

    FIGURE 7

     

  • Divide both tendons close to their femoral insertion, stopping distally at the quadratus femoris. Retract these divided tendons posteriorly, protecting the sciatic nerve with them (Fig. 7).

  • Insert Hohmann retractors superior and inferior to the capsule (Fig. 8).

FIGURE 8

77

Posterior Approach to the Hip

• Divide the capsule longitudinally, close to the femoral insertion, and curve acutely posterior at the superior capsule (where the piriformis was prior to its release), leaving small cuff attached to the femur at the superior margin of the capsule adjacent to the piriform fossa (Fig. 9).

FIGURE 9

78

Posterior Approach to the Hip

FIGURE 10

• Insert a Steinmann pin superior to the acetabulum (12 o’clock position), impacting it through both tables of the ilium, retracting the gluteus medius anteriorly (Fig. 10).

• With the hip and knee extended, mark a point 5–7 cm distal to the pin on the greater trochanter with cautery to measure leg length (Fig. 11).

   

   

   

  FIGURE 11

   

   

  79

   

   

   

  Posterior Approach to the Hip

   

  FIGURE 12

   

  • Dislocate the hip with internal rotation, adduction, and sustained gentle pressure (Fig. 12).

    • With the surgeon standing in front of the patient:

  • Cut the femoral neck perpendicular to its lateral axis at an angle/length determined from preoperative planning (Fig. 13).

     

     

     

     

    FIGURE 13

     

    80

     

     

    P EARLS

    • Place retractors between the labrum and capsule, preventing capsular excision.

       

    • Position of the limb and force of the anterior retractors may tilt the pelvis anteriorly, resulting in cup retroversion. Before final reaming and impaction of the cup, relax the retractors and leg to allow the pelvis to return to neutral. Reassess cup version.

       

      P ITFALLS

    • Placing the cup concentric with native acetabular rim may result in excessive abduction (opening).

       

    • A small amount of posterosuperior cup visible suggests adequate anteversion/ abduction.

       

    • The obturator vessels are close to the transverse acetabular ligament and can bleed profusely.

     

    Posterior Approach to the Hip

     

    Procedure

    Step 1: Acetabular Preparation/ Implantation

    • The surgeon stands on the anterior side of the patient.

• The operative leg is internally rotated, resting on the table with the patella facing the the floor.

• Posterior retractors are placed at 3 and 5 o’clock; anterior retractors are placed at 7 and 10 o’clock.

• An anteroinferior retractor displaces the femur anteriorly (Fig. 14A and 14B).

Instrumentation/ Implantation

• Aim for 45° of abduction and 15° of anteversion.

• Augment the cup with one or two 25-mm superior screws.

• Trim osteophytes after component insertion.

Controversies

• Use of screws to supplement cup fixation is controversial. It is our belief that it provides early stability, thus optimizing conditions for bone ongrowth.

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Posterior Approach to the Hip

A

Acetabular labrum

Acetabular fossa     Gluteus medius

Great trochanter

B

FIGURE 14

Posterior Approach to the Hip

82

A

B

FIGURE 15

83

Posterior Approach to the Hip

• Excise the labrum (Fig. 15A and 15B).

• Divide the transverse acetabular ligament only if it restricts insertion of reamers.

• Prepare for the chosen implant with reamers (Fig. 16).

• Practice conservative bone removal, preserving bone stock (Fig. 17A and 17B).

FIGURE 16

84

Posterior Approach to the Hip

A

FIGURE 17 B

Step 2: Femoral Preparation/Implantation

P EARLS

• An assistant is key to exposure to ensure that the hip is flexed and most importantly adducted to deliver the femoral neck into the wound.

• The surgeon stands on the posterior side of the patient.

• Flex the hip 90°, with maximal internal rotation and adduction.

• Place retractors on the inferior aspect of the femoral neck, elevating the neck (Fig. 18A).

• Place a retractor under the greater trochanter, improving exposure (Fig. 18B).

   

   

   

  85

   

  Posterior Approach to the Hip

   

  A

   

  Femur with neck cut

  Retractor elevating femoral neck

  B

   

   

   

  FIGURE 18

   

   

   

  Posterior Approach to the Hip

   

  FIGURE 19

   

  86

   

   

  P ITFALLS

  • Avoid the tendency to place the component in varus/retroversion.

     

  • Identify the piriform fossa and use a box osteotome and/or reamers laterally in the femoral neck and greater trochanter to ensure that the stem is inserted straight down the femoral shaft.

     

  • Ensure that the assistant internally rotates the hip sufficiently so that horizontal insertion of the stem gives the desired degree of anteversion (Fig. 20).

   

• Dissect the piriformis stump and residual capsule from the piriform fossa but do not excise them (see Kocher clamp attached to stump in Figure 18A).

• Visualize the residual neck and ensure an adequately lateral starting point (Fig. 19).

• Prepare the femur for the chosen implant.

   

   

   

   

  FIGURE 20

   

  Instrumentation/ Implantation

  • Insert the trial stem.

  • Insert the chosen neck and neutral-length head.

  • Reduce the hip.

   

  Step 3: Trial of Stability

  • Check for stability in extension, adduction, and external rotation (Fig. 21).

  • Check for stability in 45° of flexion/abduction (Fig. 22).

     

     

     

    87

     

     

    P EARLS

    • Check component orientation individually and combined (concentric ball in socket at 30° of abduction and 30° of flexion).

       

    • Check for impingement (anterior osteophyte/hypertrophic capsule on anterior femur).

       

    • Look at soft tissue balance (2-mm shucking with retractors released).

       

    • Does increasing the femoral neck offset and/or increasing neck length improve stability?

     

    Instrumentation/ Implantation

    • Implant the definitive femoral component.

    • Check that seating is the same as the trial.

    • Insert the chosen femoral head and reduce the hip.

    • If using a metaphyseal-fitting stem, the definitive stem should be inserted to within 1 cm of final position by finger pressure only. If it is tighter, this suggests it will be proud and it may be prudent to rebroach the femur.

    • A diaphyseal-fitting stem may sit 3–4 cm proud prior to impaction, but this should not prevent full seating of the prostheses.

     

    Posterior Approach to the Hip

     

    FIGURE 21

     

     

     

    FIGURE 22

     

    Posterior Approach to the Hip

     

• Check for stability in maximal flexion (Fig. 23A) and internal rotation (Fig. 23B).

• Measure limb length with a Steinmann pin and ruler (Fig. 24).

   

   

   

  88

   

  A

   

   

   

  B

  FIGURE 23

   

   

   

   

  P EARLS

  • Internal rotation of the hip will make it easier to find the capsule and piriformis tendon attached to the greater trochanter. External rotation and abduction will then help to repair the capsule and piriformis tendon, approximating the edges while they are being sutured. Gentle relaxation of this position will allow the repaired tissues to tighten, but the sutures should not cut out.

   

  Posterior Approach to the Hip

   

  FIGURE 24

   

  89

   

  Step 4: Closure, after Insertion of

  Definitive Components

  • Good closure and elimination of posterior “dead space” is a key step to a successful and stable outcome.

  • Repair the capsule flap from the posterior acetabulum to the stump of the piriformis/adjacent capsule with interrupted sutures (Fig. 25A and 25B).

A B

FIGURE 25

90

P ITFALLS

• Extensive posterior osteophytes may obliterate or replace the capsule, and subsequent removal may result in little or no capsule to repair. As described earlier, try to dissect the capsule off the osteophyte during the capsulotomy.

   

• Restoring length in a contracted or short hip or increasing offset will make posterior closure more difficult.

   

• If direct posterior capsular repair is not possible, try to repair the piriformis to its stump rather than the gluteus medius tendon to get tissue as close to the posterior aspect of the hip as possible, minimizing dead space.

Posterior Approach to the Hip

• Repair the piriformis and conjoined tendon to the tendinous insertion of the gluteus medius with horizontal mattress and figure-of-eight sutures (Fig. 26A–26D).

• Repair the fascia lata and then close the subcutaneous tissues and skin.

P EARLS

• Use hip precautions to protect the posterior repair while scar tissue forms (empirically, 6 weeks).

• Use an abduction wedge during recovery from anesthesia.

   

• Flexion is restricted to 90° (toilet seats and chairs may need to be raised).

• No internal rotation is allowed.

   

• Unrestricted use of the abductor muscles is permitted (their strength will improve hip stability).

   

  P ITFALLS

• Dislocation, if it occurs, frequently happens in the first few weeks.

• Emphasize the importance of avoiding extreme flexion and any internal rotation.

A B

FIGURE 26

Posterior Approach to the Hip

C D

FIGURE 26, cont’d

91

Postoperative Care and Expected Outcomes

• Weight bearing is determined by prostheses used.

• Possible complications include thromboembolism, heterotrophic ossification.

• Antibiotic prophylaxis may be necessary.

Evidence

Gibson A. Posterior exposure of the hip joint. J Bone Joint Surg [Br]. 1950;32:183–6.

This classic paper discusses the history of the posterior approach described first by Von Langenbeck in 1874 and modified by Kocher in 1887. Gibson uses the same skin incision we describe but retracts the gluteus maximus posteriorly en masse and releases the conjoined tendon, gemelli, piriformis, and gluteus medius and minimus from the greater trochanter. He then describes excising the anterior hip capsule and dislocating the hip anteriorly (as in a lateral approach). His indications include sciatic nerve exploration, arthrodeses, and cup arthroplasty.

Jolles BM, Bogoch ER. Posterior versus lateral surgical approach for total hip arthroplasty in adults with osteoarthritis. Cochrane Database Syst Rev. 2006;(3): CD003828.

Parker MJ, Pervez H. Surgical approaches for inserting hemiarthroplasty of the hip. Cochrane Database Syst Rev. 2002;(3):CD001707.

These systematic reviews conclude that there is no evidence showing different dislocation rates or abductor function in comparing lateral and posterior approaches. The surgeon may hence choose either approach. We prefer the posterior approach as it doesn’t intefere with the gluteus medius or minimus, splitting but not detaching the gluteus maximus.

92

Posterior Approach to the Hip

Konyves A, Bannister GC. The importance of leg length discrepancy after total hip arthroplasty. J Bone Joint Surg [Br]. 2005;87:1307.

Review of 90 cases of primary total hip arthroplasty. Of these, 56 cases were lengthened by a mean of 9 mm, and those who noticed their lengthening had worse hip scores at 3 and 12 months. This highlights the importance of trying to achieve correct leg length.

Moore AT. The Moore self-locking vitallium prosthesis in fresh femoral neck fractures: a new low posterior approach (the Southern Exposure). AAOS Instr Course Lect.

1959;16:309.

This classic paper discusses Moore’s results with his prostheses and also his “Southern exposure,” wherein the skin incision is in the low part of the buttock, near the “south side.” His indications are for arthrodeses, arthroplasty, congenital dislocation, and osteotomy. He discusses the difficulty of performing arthroplasty through an anterior approach, which led him to pursue the posterior approach. The skin incision curves posteriorly 4 inches below the posterior superior iliac spine, placing the incision directly over the sciatic nerve, which is dissected free after a low split in the gluteus maximus muscle belly. His exposure is then similar to the one we have described, with detachment of the piriformis and the gemelli/obturator internus plus a portion of quadratus femoris before capsulotomy and posterior dislocation.

Pellicci PM, Bostrum M, Poss R. Posterior approach to total hip replacement using enhanced posterior soft tissue repair. Clin Orthop Relat Res. 1998;(355):224–8.

This retrospective study demonstrated that the dislocation rates were reduced from 4% to 0% and from 6.2% to 0.8%, respectively, when two surgeons changed technique from no or minimal soft tissue repair to an anatomic repair of short rotators and capsule. The authors comment that, although the repair itself is not sufficiently strong to prevent dislocation, it eliminates dead space and encourages scar tissue to form adjacent to the arthroplasty. This paper highlights the importance of soft tissue repair.

Vinton CJ, White K, Wixted JJ, Varney D, Waddell J, Kavanagh B. The effect of body mass index and surgical approach on post-operative limp in total hip arthroplasty. Presented at the AAOS 71st Annual Meeting, San Francisco, March 2004.