- See:
Posterior Approach for Pelvic Frx:
- Indications for Use:
- isolated
posterior wall &
posterior column frxs;
- allows access to posterior column and posterior wall only, but exposure
is limited proximally by
superior gluteal vessels and greater trochanter;
- isolated
transverse frx (as well as associated transverse frxs and posterior wall frx);
-
T shaped fractures (may also use extended
iliofemoral approach);
- PreOp Planning:
- foley catheter;
-
distal femoral traction pin;
- consider use of spontaneous
EMG w/ needles placed in the tibialis anterior and peroneus longus (inorder
to asses the peroneal division of the
sciatic nerve) and needles placed in the abductor hallucis
and flexor hallucis longus muscles (which are innervated by the posterior tibial nerve);
- spontaneous EMG allows real time monitoring of potenital sciatic palsy;
- Positioning:
- options include prone positioning, lateral positioning, or lateral positioning on the fracture table;
- some surgeons prefer the lateral position for posterior wall fractures and the prone position for posterior column fractures;
- avoid injury to the
sciatic nerve;
- to protect the nerve the knee must be in flexion at all times
- Exposure:
- mark out PSIS, sciatic notch, and greater trochanter;
-
incision:
- incision begins lateral to PSIS, crosses the most anterior portion of the notch, and
subsequently crosses the posterior 1/3 of the greater tuberosity;
- incise the skin, subQ tissues, and
tensor fascia lata & blunting split the fibers of the
maximus;
- excessive proximal spliting of the maximus may injure the
inferior gluteal nerve;
- release a portion of the gluteal sling for additional exposure (noting that the
major insertion of the maximus is to the IT band);
- trochanteric bursa is incised from distal to proximal, which helps to identify the posterior edge of
the gluteus medius and places the surgeon at the correct plane for identifying the sciatic nerve;
-
sciatic nerve is identified:
- at this point, identify:
piriformis,
quadratus femoris, &
sciatic nerve;
- sciatic nerve is identified on the superficial surface of the quadratus muscle;
- note any contussions or discolorations of the nerve;
- to protect the nerve the knee must be in flexion at all times;
- carefully mobilize the sciatic nerve from its bed of areolar tissue and pass a penrose drain around it for identification;
- a nerve stimulator may be used to ensure that both divisions of the nerve are contained in the penrose drain;
- the hip remains extended and the knee flexed through out the procedure inorder to protect the nerve;
-
superior elevation of the medius:
- identify the interval between the
gluteus medius and the piriformis;
- elevate the gluteus medius (off the pelvis) and retract it superiorly;
- then drive a large Steiman pin into the ilium at a point well above the acetabulum, which will keep
the medius retracted superiorly throughout the case;
-
reflect short external rotators:
- develop the plane between the external rotators and the underlying hip capsule (w/ a periosteal elevator inserted just above
the piriformis and directed distally);
- the piriformis and the conjoined tendon (gemelli and the obturator internus) are tagged for later repair;
- be careful not to dissect around or injury the quadratus so as to avoid injury to the
MFCA;
- reflect short
external rotators off of their insertion and reflect them posteriorly inorder to protect the nerve;
- note that in some cases the external rotators can be partially avulsed from their origin;
-
greater sciatic and lesser sciatic notch:
- identify the
greater and lesser sciatic notch;
- injury to
superior gluteal artery &
nerve must be avoided;
- they can be visualized exiting from
greater sciatic notch;
- exposure of ilium will be limited because superior gluteal artery & nerve enter the
medius and minimus limiting upward mobilization;
- once the greater sciatic notch is adequately exposed, insert a curved homan retractor;
- the reflected external rotators should protect the sciatic nerve from the Homan;
- a second homan rectrator is placed into the lesser sciatic notch, just below the ischial spine;
- take care not to injure the pudenal artery;
- this will help retract the conjoined muscles and the sciatic nerve posteriorly;
-
greater trochanteric osteotomy:
- patients undergoing osteotomy may be at greater risk for
heterotopic ossification;
-
sliding osteotomy may be procedure of choice;
- this type of osteotomy facilitates visualization of the superior aspect of the hip capsule;
- performed correctly, this type of osteotomy should not interfere w/
MFCA and
blood supply to the hip;
- distal end of trochanter is left attached to the vastus lateralis and the proximal end attached to the gluteus medius and minimus;
- reference:
-
Osteotomy of the Trochanter in Open Reduction and Internal Fixation of Acetabular Fractures.
- Direct complications of trochanteric osteotomy in open reduction and internal fixation of acetabular fractures.
BE Heck et al.
Am J. Orthop. Vol 26(2) 1997 Feb. p 124-128.
- Trochanteric flip osteotomy for cranial extension and muscle protection in acetabular fracture fixation using a Kocher-Langenbeck approach.
KA Siebenrock et al.
J. Orthop Trauma Vol 12. No 6. 1998. p 387.
-
other measures to improve exposure:
- origin of the hamstrings can be elevated from the ischial tuberosity to expose the lower posterior column;
- hip capsule can be released from the intact portion of the acetabular rim (perimeter of the labrum);
- these measures may allow for visualization of the femoral head (after hip dislocation), femoral head debridemont, and management of
associated fractures (such as transverse fracture or posterior wall fractures);
- Deep Exposure:
-
exposure of posterior column:
- entire
posterior column of the acetabulum is exposed;
- using blunt dissection, elevate medius from outer side of ilium;
- consider
femoral distractor:
- consider
trochanteric osteotomy:
- if visualization of superior dome and
anterior column is needed;
- for difficult
transverse or
T type frxs;
-
exposure of the posterior wall: (see:
posterior wall)
- determine whether there is any pre-existing posterior capsular stripping;
- posterior capsulotomy is performed by detaching it from its acetabular origin;
- detachment from the femoral origin may disrupt the
blood supply to the femoral head,
which could lead to
AVN;
-
quadrilateral surface:
- may be palpated through the greater or lesser sciatic notch;
-
dislocation of hip:
- indicated for interposed intra-articular fragments;
- consider sliding trochanteric osteotomy for easier dislocation;
- consider intra operative drilling of the femoral head inorder to demonstrate perfusion;
- Complications:
-
sciatic nerve palsy:
- most common cause of palsy is retraction of sciatic nerve;
- to avoid palsy, keep patient's knee flexed at least 60 deg & hip extended;
- if sciatic nerve palsy occurs, it is treated initially with an AFO,
- there may be improvement in the palsy for upto 3 years;
Femoral artery thrombosis after open reduction of an acetabular fracture.
Fractures of the Acetabulum: accuracy of reduction and clinical results in patients managed operatively with in three weeks after the injury. JM Matta.
JBJS-Am.
78 (11) Nov 1996. p 1632-1645.
Gluteus minimus necrotic muscle debridement diminishes heterotopic ossification after acetabular fracture fixation.
Trochanteric Flip Osteotomy for Cranial Extension and Muscle Protection in Acetabular Fracture Fixation Using a Kocher-Langenbeck Approach.
Long-term results in surgically treated acetabular fractures through the posterior approaches.
Surgically treated acetabular fractures via a single posterior approach with a follow-up of 2-10 years.
