What is Pubic Symphysis? Essential Definition & Implications

DEFINITION Chapter2
Open Reduction and Internal Fixation of the Symphysis

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Michael S. H. Kain and Paul Tornetta III DEFINITION ■The pubic symphysis comprises a fibrocartilaginous disc between the bodies of the two pubic bones.
■A diastasis of the pubic symphysis indicates a disruption of the pelvic ring and an unstable pelvis.
■The symphysis is disrupted in anterior–posterior compres- sion (APC) injuries as classified by Young and Burgess and oc- casionally in lateral compression fractures. ANATOMY ■The symphysis is an amphiarthrodial joint, consisting of a fibrocartilaginous disc, and stabilized by the superior and in- ferior arcuate ligaments (FIG 1A).
■The corona mortis is a vessel that represents the anasto- mosis between the obturator artery and the external iliac artery. It is located about 6 cm laterally on either side of the symphysis (FIG 1B).14
■Lateral to the symphysis on the superior rami is the pubic tubercle, a prominence representing the attachment of the in- guinal ligament.
■This bony landmark must be accounted for when con-
touring a plate that is going to span the symphysis.
■Anatomic variation exists between the sexes, with females having a wider and more rounded pelvis, making their anterior pelvic ring more concave than males (FIG 2).
■The pelvic arch formed by the convergence of the inferior
rami tends to be more rounded in females because their
pubic bodies are shallower than males.

Pubic arch
■The arcuate ligaments are the main soft tissue stabilizers of the anterior pelvis.
■These ligaments arc both superiorly and inferiorly and are
firmly attached to the pubic rami.
■The sacrospinous and sacrotuberous ligaments play an im- portant role in the stability of pelvic fractures. These ligaments connect the sacrum to the ilium via the ischial spine and the is- chial tuberosity. The sacrospinous ligament resists the rota- tional forces of the hemipelvis, and the sacrotuberous ligament prevents rotation as well as translation of the hemipelvis.13
■If these ligaments and the pelvic floor are torn in conjunc-
tion with a pelvic fracture, symphyseal widening is more sig-
nificant (see Chap. TR-1).4 PATHOGENESIS ■The Young and Burgess classification describes the injury by the type of force acting on the pelvis. Symphyseal diastasis is most commonly seen in APC injuries or open book pelvis injuries.
■In APC injuries minor widening of the symphysis may not in- volve disruption of the pelvic floor, including the sacrospinous ligaments.
■In cadaver pelvi, where the symphysis and sacrospinous lig- aments were sectioned, more than 2.5 cm of symphyseal widening was observed, thus defining a rotationally unstable pelvis.12
■If the pelvic floor and the sacrospinous ligaments are torn,
the involved hemipelvis can externally rotate down and out,
External iliac a.
Arcuate ligaments
Pubic tubercle
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Rectus
abdominis m. Interior
epigastric a.

| Coronamortis a. Obturator a.
A B
FIG 1•A.View of the anterior pelvis demonstrating the fibrocartilaginous disc between the pubic bodies, the superior and inferior arcuate ligaments, and the relationship between the symphysis and the pubic tubercles. B.The corona mor- tis is demonstrated on the inside of the superior pubic rami about 6 cm from the symphysis. It represents the anastomo- sis of the obturator artery and the external iliac artery.
476
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A
B
Chapter 2ORIF OF THE SYMPHYSIS477
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FIG 2•Examples of the anatomic variants between genders. The female pelvis has a more concave shape to the ring and the pubic arch has less of an acute
angle because of the broader pubic body, as demon- strated in the inlet (A) and outlet (B) views of a fe-
male pelvis. The male pelvic ring is more oval, with a much more acute angle anteriorly because of the
thinner pubic body, as seen the corresponding inlet
C D
rotating on the intact posterior sacroiliac ligaments and cre-
ating an unstable pelvis (FIG 3).4
■Occasionally, lateral compression (LC) injuries involve frac- tures of the pubic rami and a symphyseal disruption. This oc- curs when the compressed hemipelvis causes the contralateral rami to fracture and the contralateral symphyseal body to tilt inferiorly. Because one side of the symphysis is off and can

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FIG 3•The hemipelvis externally rotates out when the posterior sacroiliac ligaments remain intact, as in an anterior–posterior
compression type II injury. The posterior ligaments act as a
hinge, and with sacrospinous ligaments torn the involved
hemipelvis will rotate down and out, so the pubic body on the injured side will be below the intact pubic body.
(C) and outlet (D) views.
compress the bladder or uterus, altering the pelvic ring, it should be reduced to the other pubic body, which remains intact.
■These are referred to as tilt fractures, and open reduction
and internal fixation should be considered to prevent im-
pingement of the birth canal and bladder.13
■A diastasis of the pubic symphysis can also occur in pregnancy and during childbirth because of hormonally induced ligamen- tous laxity. This can lead to chronic instability, and stabilization of the symphysis has been shown to relieve painful symptoms.16 NATURAL HISTORY ■Persistent low back pain, anterior pain, sitting imbalance, and an impaired, painful gait are common sequelae after pelvic fractures.
■Early studies looking at pelvic fractures without surgical treatment demonstrated that almost a third of these patients had disabling pain and impaired gait. Only a third had no symptoms if the posterior ring was involved.16
■APC type I injuries are Tile type A stable pelvic injuries, which do well with nonoperative treatment. These injuries tend to occur in younger patients involved in motor vehicle trauma or in elderly patients as a result of a direct injury such as a fall.
■APC type II and III injuries are unstable injuries. Non- operative treatment has resulted in late pain in these injuries. In a retrospective study by Tile, APC type II injuries treated non- operatively had a 13% incidence of late pain, with the major- ity of patients reporting persistent moderate pain. The patients with APC type III injuries reported a 16% incidence oflate pain, with most pain being reported as moderate or severe.13 ■Patients with pelvic trauma tend to have other organ sys- tems involved, and these associated injuries contribute to long- term disability. The more severe injuries associated with pelvic fractures are urologic and neurologic injuries.16
■Whitbeck et al demonstrated higher morbidity and mortal- ity rates as well as an increased incidence of arterial injuries in APC type III injuries compared to other pelvic fractures.18
478 Part2PELVIS AND LOWER EXTREMITY TRAUMA•Section IPELVIS AND HIP
■Disruption of the pubic symphysis is associated with uro- logic injuries. Bladder ruptures and urethral tears occur about 15% of the time in association with pelvic trauma and can lead to late complications such as strictures and incontinence. These associated injuries potentially lead to a higher infection rate when open reduction and internal fixation is performed.8 An increased incidence of incontinence has also been seen in women with APC injuries.
■Neurologic injuries associated with pelvic fractures occur when there is posterior pathology and are more common with
sacral fractures and vertically unstable fracture patterns.
■Dyspareunia and sexual dysfunction are also described as com- plications after pelvic fractures.7They can occur directly from the injury or as a result of ectopic bone formation during healing.
■Symphyseal pelvic dysfunction, a relatively common condi- tion, presents as anterior pelvic pain secondary to the laxity in the symphysis. This condition typically resolves spontaneously and can take some time but needs to be differentiated from trau- matic symphyseal diastasis as a result of childbirth. Traumatic diastasis occurs in about 1 in 2000 births to 1 in 30,000 births, and the diastases from pregnancy can be as great as 12 cm.3
■Most patients with postpartum displacement recover with no residual pain or instability after treatment with pelvic binders, girdles, and the recommendation to lie in the lateral decubitus position.
■There are a limited number of studies looking at symphyseal disruption secondary to pregnancy. The exact incidence of per- sistent long-term pain is unknown, but chronic pelvic instabil- ity can occur if it is unrecognized.9
■In the few series reporting operative treatment, the indication was persistent pain for at least 4 to 6 months postpartum.3,9 PATIENT HISTORY AND PHYSICAL FINDINGS ■Pelvic injuries usually occur as a result of any high-energy trauma, such as high-speed motor vehicle accidents, motorcy- cle accidents, or falls from heights.
■Patients with pelvic fractures may become hemodynamically unstable, and close monitoring of blood pressure and fluid re- quirements is needed.
■Typically, if a patient requires more than 4 units of blood
to maintain hemodynamic stability, an angiogram should be
obtained to diagnose and embolize any arterial injuries.
Clotting factors and platelets should also be administered.
■Patients may have tenderness to palpation in the area of the symphysis. If motion of the pelvis is detected, manipulation of the pelvis should cease, as unnecessary manipulation may dis- turb any clot formation (see Exam Table for Pelvis and Lower Extremity Trauma, pages 1 and 2).
■If there is no radiographic demonstration of displacement, the iliac wings can be compressed to test for stability of the pelvic ring and each hemipelvis.
■A careful examination of the skin to identify areas of ecchy- mosis and hematoma formation, particularly in the flanks, groin, and abdominal regions, also needs to be performed.
■The presence of a Morel-Lavalle lesion indicates that high-
energy trauma has occurred in the pelvic region (FIG4).
Recognition of this lesion is important to prevent infection.
■A good pelvic examination and evaluation of the perineum are essential. Swelling or open wounds in the perineal area may indicate a high-energy mechanism of injury. Open injuries require emergent management.
FIG 4•Morel-Lavalle lesion.
■Evaluation of other organ systems, looking for associated injuries, is essential.
■In males, a high-riding prostate on the rectal examination
or blood at the meatus may indicate injury to the urethra or
bladder, and placement of a Foley catheter should be de-
layed until a retrograde urethrogram is performed, unless
the patient is in extremis.
■Urethral injuries are less common in females because the
urethra is shorter.
■A thorough neurologic examination of the lower extremities also needs to be performed, as injuries to the L4 and L5 nerve roots can occur in pelvic fractures. It is essential to test the sen- sation and motor functions of specific roots, identifying any neurologic injury that can differentiate between a nerve root lesion or a more central lesion.
■A limb-length discrepancy or a rotational deformity of the lower extremities should prompt radiographic evaluation of the pelvis. IMAGING AND OTHER DIAGNOSTIC STUDIES ■Radiographic evaluation of the pelvis consists of anteropos- terior (AP), inlet, outlet, and Judet views (FIG 5).
■A retrograde urethrogram and sometimes a CT cystogram should be performed to rule out an injury to the genitourinary system in men. A CT cystogram is sufficient for females.
■A CT scan of the pelvis is also indicated to help evaluate intra-articular injuries to the sacroiliac joints and further delin- eate the fracture pattern.
■A CT angiogram can also be used at the time of the trauma scan to help predict if an arterial bleed is present and requires further treatment with angiography and embolization.10
■Angiography may be used to treat patients who are hemody- namically unstable and do not respond to standard resuscita- tion, particularly if a CT angiogram indicates arterial bleeding. ■A stress examination in the operating room can be per- formed under fluoroscopy to assess stability if there is a ques- tion of an unstable pelvis.
■Single-leg stance views can also be performed if it is not clear whether an injury is unstable. This is a good examination for evaluating patients who may have chronic instability, such as a female patient with ligamentous laxity secondary to preg- nancy or unrecognized pelvic injury.9,14 DIFFERENTIAL DIAGNOSIS ■Rami fractures
■Symphyseal strain
■Hip fracture
Chapter 2ORIF OF THE SYMPHYSIS479
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A B C
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FIG 5•Appropriate AP (A), inlet
(B), outlet (C), and Judet views
(D,E) of the pelvis in a patient with pelvic trauma and wide pubic sym- physis. (Courtesy of Jodi Siegel,
D E
■Muscle strain or avulsion
■Lumbar fracture
ACUTE MANAGEMENT ■The patients should be hemodynamically stabilized.
■The pelvis can be stabilized by placing ankles together with Ace wraps. Heels and ankles should be padded to prevent skin breakdown and ulcer formation.
■Placing a sheet across the pelvis at the level of the greater trochanters can be used to reduce the symphysis and tem- porarily stabilize the pelvis. The sheet can be affixed with towel clips to hold it with tension rather than tying a knot across the abdomen (see Chap. TR-1). NONOPERATIVE MANAGEMENT ■If minimal separation of the symphysis is present, the pa- tient can be made non-weight bearing on the affected side and can be allowed to ambulate.
■Close radiographic monitoring should ensue, with weekly radiographs. Single-leg stance views can be used to help iden- tify late instability. SURGICAL MANAGEMENT ■A diastasis larger than 2.5 mm indicates a disruption of the sacrospinous ligaments and thus an unstable pelvis. Open fix- ation of the symphysis stabilizes the anterior pelvis.2
■Open injuries can be stabilized with external fixation, using iliac wing pins or Hanover pins placed at the level of the ante- rior inferior iliac spine. Refer to Chapter TR-1 for more details. ■In APC type II injuries with an intact hemipelvis, no poste- rior fixation is needed, and the symphysis is reduced and stabilized first.
■For type III injuries, if the innominate bone is broken, the anterior pelvic ring is reduced and fixed after the posterior ring is reduced and fixed. The anterior pelvic ring is reduced
MD, and David Templeman, MD.)
and fixed as a first step if the innominate bone remains intact.
■Indications for anterior stabilization for vertically unstable pelvic fractures include improving anterior stability to thepelvic ring, stabilizing a pelvic injury that is associated with an injury requiring a laparotomy, treatment of bone pro- truding into the perineum (ie, a tilt fracture), or in association with an acetabular fracture requiring open reduction.13 Preoperative Planning ■The surgeon should review appropriate radiographic studies (AP, inlet, and outlet views and CT scan).
■Identifying all rami fractures and the presence of any
pubic body fractures is essential, as this will help determine
how to obtain a reduction as well as dictate the type of
fixation necessary.
■The surgeon should plan to obtain stress views in the oper- ating room to determine the stability of the pelvis if there is any question of stability.
■The surgeon should rule out the presence of a bladder rupture or urethral tear. If one is present, repair should beper- formed at the same time as internal fixation of thesymphysis if possible to avoid a more complex late reconstruction.
■Any history of previous abdominal surgery or the presence of prior incisions should be identified before going to the op- erating room.
■The proper equipment must be available, such as C-arm, ra- diolucent table, large bone clamps, external fixation equip- ment, and a C-clamp. Positioning ■The patient is placed on a radiolucent flat-top table with legs together to facilitate reduction of the symphysis.
■Fluoroscopic radiographs confirming the ability to obtain a good inlet and outlet views with the C-arm are obtained before preparing and draping the patient.
480 Part2PELVIS AND LOWER EXTREMITY TRAUMA•Section IPELVIS AND HIP
■Right-handed surgeons may prefer to have the C-arm onthe patient’s right side and the drill and instruments on the pa- tient’s left for easier access to the symphysis with the drill.
■Placement of a Foley catheter is needed to decompress the bladder; it can also be felt intraoperatively to help identify the bladder.
■Venodyne boots are placed on both legs if possible for deep vein thrombosis prophylaxis during the case. Approach
■Open reduction of the symphysis is performed with an ante- rior Pfannenstiel approach.

| PFANNENSTIEL APPROACH ■The entire lower abdomen is prepared, including both
anterior superior iliac spines, the symphysis, and the
umbilicus. ■Access to the anterior superior iliac spines is impor-
tant if an external fixator is to be placed to assist in
reduction or for additional fixation. ■A transverse incision is made 2 cm above the symphysis
(TECH FIG 1A). ■Once through the skin, a large rake is placed to help cre-
ate a plane above the rectus fascia. ■A longitudinal incision is then made along the fascia of
the linea alba. The rectus muscle insertion is not taken
down, although it is common to see an avulsion of one
of the rectus muscles off the rami from the initial injury
(TECH FIG 1B). ■Blunt dissection is continued longitudinally to spread the
rectus muscle and protect the underlying peritoneum
and bladder. ■Electric cautery can be used to divide the remaining
fibers of the rectus while protecting the underlying
structures. | ■The bladder and bladder neck are evaluated for the pres-
ence of any injury. ■At this point, a blunt malleable retractor can be placed
into the space of Retzius to protect the bladder (TECH
FIG 1C). ■Care should be taken laterally, as the vessels known as
the corona mortis tend to be about 6 cm lateral to the
symphysis. ■The corona mortis is an anastomosis of the obturator
and external iliac arteries (see Fig 1B).14 ■Hohmann retractors are placed through the periosteum
superiorly over the superior pubic rami one side at a time
to retract the rectus muscle laterally and expose the su-
perior body of the symphysis. ■These retractors are placed close to the external iliac
vessels, so they need to be placed with care directly
onto bone. ■The periosteum on the superior aspect of the rami can now
be stripped off with an electric cautery and osteotomes. ■ Some surgeons remove the symphyseal cartilage to pro-
mote fusion, and we agree with this approach.
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A B C TECH FIG 1•A.The skin is marked for the incision. The entire lower abdomen is prepared, to include the umbili- cus and both anterior superior iliac spines as well as the anterior inferior iliac spines bilaterally. An incision is marked about two fingerbreadths superiorly to the pubic bones. B.The linea alba is clearly identified once the subcuta- neous fat has been dissected away from the fascia. An incision along the linea alba, between the two rectus mus- cles, is made to allow exposure of the space of Retzius. C.Once the space of Retzius is exposed, a dever or blunt re- tractor is used to retract the bladder and two Hohmann retractors are placed on the outside of each superior rami to expose the superior aspect and allow reduction and plating.
| WEBER CLAMP REDUCTION ■Once the superior aspect of the symphyseal bodies is ex-
posed, the Weber clamp is placed anteriorly to avoid re-
moving the insertion of the rectus (TECH FIG 2A). ■The goal in using this technique is to have the tips of the Weber clamp at the same level on each symphyseal body. | ■ If anterior displacement is present on either side, the tip
of the clamp is placed slightly anterior on that side so at
the time of reduction the tips are at the same level.4 ■The clamp is tilted distally to engage the tines (TECH FIG 2B). ■The clamp is placed anterior to the rectus insertions.



Chapter 2ORIF OF THE SYMPHYSIS481

A B TECH FIG 2•A.Weber clamp or large bone tentaculum is used to reduce the symphysis with the
tines at the same level on each pubic body anterior to the rectus muscle. B.Tilting the clamp dis-
| tally will help engage the tines. |
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USE OF A C-CLAMP TO AID IN REDUCTION ■The C-clamp has been described for use in unstable APC
pelvic fractures in patients requiring an exploratory la-
parotomy or as temporary pelvic fixation if the patient
cannot go to the operating room. It can also be used to
assist in the open reduction of the symphysis if conven-
tional clamps cannot hold the reduction. ■This is a similar concept to the one described by Wright
et al for assisting in the reduction of the posterior pelvic
ring.17 ■To apply the C-clamp, the pins are placed two finger-
breadths directly posterior to the anterior superior iliac
spine. This places the pins in the gluteus pillar, a thick-
ened portion of the lateral ilium above the acetabulum
(TECH FIG 3A). A B C TECH FIG 3•Placement of pins for the C-clamp (A) and how it is applied to obtain a reduction of the symphysis (B,C).







482 Part2PELVIS AND LOWER EXTREMITY TRAUMA•Section IPELVIS AND HIP
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| JUNGABLUTH CLAMP REDUCTION (TECHNIQUE OF MATTA)
■ Jungabluth clamp reduction is used when the innomi-
nate bone is intact and the posterior ring is unstable. ■The innominate bone tends to be externally rotated, pos-
teriorly displaced, and superiorly translated. If this is the
case or vertical instability exists, the entire innominate
bone needs to be manipulated to obtain a reduction. ■ In these cases, the use of the Jungabluth clamp may
be necessary to achieve reduction. ■Drill holes are made in an anterior-to-posterior direction
for the placement for 4.5-mm screws. ■ For the screw being placed on the unstable side (with posterior displacement), a 4.5-mm gliding hole is drilled | and the screw is secured to the bone through a small
plate on the posterior side of the pubis using a nut (TECH
FIG 4A,B). ■The plate will act as a washer and provides a larger
surface area of force to be exerted on the hemipelvis
so one does not have to rely on the pullout strength
of a single screw. ■The Jungabluth clamp is then placed anteriorly and se-
cured to the 4.5-mm screws and can then be used to
achieve the reduction (TECH FIG 4C,D).5
A B C D TECH FIG 4•The Jungabluth clamp can be used to reduce the symphysis if there is posterior translation of the hemipelvis and intact innominate bone. A,B.On the side of the displacement, a screw is placed with a small plate attached with a nut so the plate acts a washer. C,D.The clamp is then attached to the head of the screw and is used to pull the hemipelvis forward to reduce the symphysis. A gliding hole must be used so the clamp pulls through the plate and does not rely on the pullout strength of a single screw. (Adapted from Matta JM, Tornetta P. Internal fixation of pelvic fractures. Clin Orthop Relat Res 1996;329:129–140.)








Chapter 2ORIF OF THE SYMPHYSIS483
PLATE PLACEMENT ■Before fixation placement, the reduction should be con-
firmed on the AP, inlet, and outlet views with the C-
arm. ■With the symphysis reduced, a six-hole, curved 3.5 recon-
struction plate or precontoured plate is placed across the
symphysis. ■A Kirschner wire can be placed into the fibrocartilagi-
nous disc space to aid in centering the plate. ■Before the plate is placed, it is contoured to fit the
curve of the superior surface of the symphysis and
rami. The ends are contoured if a six-hole plate is used
to allow foranatomic contact to the ramus (TECH
FIG5A). Alternatively, precontoured plates can be
used. ■ In a six-hole plate, the two medial screws on each side
go into the symphyseal body and the most lateral
screw goes into the rami. A &nb