Download Overview on Pelvic Resections: Surgical

13282_ON-17.qxd
3/22/09
10:45 AM
Page 1
Chapter
17
Overview on Pelvic Resections:
Surgical Considerations
and Classifications
Ernest U. Conrad III, Jason Weisstein, Jennifer Lisle,
Amir Sternheim, and Martin M. Malawer
BACKGROUND
Obturator Nerve
The pelvis is a relatively common anatomic location for
metastatic and primary musculoskeletal tumors. Surgical resection is more challenging in the pelvis than in other locations
because of the complex anatomy and the proximity to vital abdominal viscera and major blood vessels and nerves. Making
decisions about surgical resectability of a tumor involves the
assessment of possible osseous or neurovascular involvement,
in addition to the possible involvement of adjacent viscera
(ie, bowel, ureter, and bladder). Therefore, preoperative evaluation and extensive imaging are critical. Osseous resection
and reconstruction usually are carried out adjacent to major
nerves, beneath the iliac vessels, or adjacent to the bladder or
bowel.
■ Tumor surgery around the pelvis has the highest rate of
complications, infections, and mechanical failure of all
anatomic sites.
■
■
ANATOMY (FIG 1)
Pelvic Nerves
Sciatic Nerve
The sciatic nerve arises from L4, L5, S1, S2, and S3. The
nerve emerges from the pelvis through the greater sciatic notch
inferior to the piriformis muscle and enters the thigh lateral to
the ischial tuberosity. In 10% of patients, the sciatic nerve penetrates the substance of the piriformis muscle. The sciatic
nerve is accompanied by the inferior gluteal artery.
■ It is essential to protect the sciatic nerve early in most procedures. Inside the pelvis, the nerve should be identified distally at the greater sciatic notch. Proximally, it should be
picked up below the psoas muscle. The sciatic nerve is formed
at the junction of the lumbar sacral plexus where these two
trunks come together.
■ Great care must be taken as the nerve exits the pelvis at the
level of the greater sciatic notch not to injure the the accompanying inferior and superior gluteal nerves and arteries, because
these supply the abductors as well as the gluteus maximus
muscle. The gluteus maximus muscle is essential for closure of
most pelvic resections.
■
Femoral Nerve
The femoral nerve arises from posterior divisions of the ventral rami of L2 and L3 and passes inferolaterally between the
psoas and iliacus muscles. It passes over the superficial iliacus
muscle to enter the proximal thigh underneath the inguinal ligament, just lateral to the superficial femoral artery.
■ This nerve is almost always preserved during pelvic resections. It should be identified early during most procedures.
The femoral nerve is identified in the space between the iliacus
and psoas muscles as they exit the pelvis. The femoral nerve
lies just below the fascia, bridging the interval between the two
muscles, lateral to the femoral artery and vein.
■
The obturator nerve, formed from the anterior branches of
L2, L3, and L4, is the largest nerve formed from anterior divisions of the lumbar plexus. The nerve descends thru the iliopsoas muscle and courses distally over the sacral ala into the
lesser pelvis, lying lateral to the ureter and under the internal
iliac vessels. It then traverses the obturator foramen into the
medial thigh, under the superior pubic ramus, dividing into
anterior and posterior branches.
■ This nerve is routinely transected during pelvic floor resections (type 3) due to its intimate proximity to the tumor.
Lumbar Plexus Sensory Nerves
The iliohypogastric (L1), ilioinguinal (L1), genitofemoral
(L1, 2) and lateral femoral cutaneous nerves, which arises
from L2 and L3, travel downward laterally along the iliopsoas
muscle, pass underneath the lateral aspect of the inguinal ligament, and pass just distal and medial to the anterior superior
iliac crest to innervate the anterolateral thigh.
■ This nerve is sacrificed during most pelvic surgical procedures.
■
Pelvic Vessels
Aortic Bifurcation
Descending the abdomen to the left of the vena cava, the
aorta bifurcates at the level of L4 into common iliac vessels at
the level of L4–L5. The common iliac bifurcates into internal
and external iliacus vessels at the level of S1, the ala sacralis.
The level of these bifurcations may vary, especially if the vessels are pushed by a large adjacent tumor mass.
■ It is essential to identify two levels of bifurcations prior to
any ligation: the aortic bifurcation and the common iliac bifurcation. Even the best surgeons have ligated the wrong vessels
due to distorted anatomy. Such a misstep is especially possible
with tumors that cross the midline. Preoperative evaluation
with angiography is required for evaluation and preoperative
to avert such an occurrence.
■
Common Iliac Artery
The common iliac artery must be identified early to correctly
identify the aorta as well as the the internal iliac (hypogastric)
artery. To the surgeon, the major anatomic features of the
common iliac artery are as follows:
■ No arterial branches arise from the artery (although the
common iliac vein does have a major branch joining in, the
iliolumbar vein)
■ The bifurcation of the common iliac artery into the external and internal iliac arteries is at the exact level at which
the ureter crosses on the adjacent peritoneal surface. The
ureter is routinely identified at this location early in the
retroperitoneal dissection.
■
External Iliac Artery
The external iliac artery contributes to the inferior epigastric
artery and extends distally, as the superficial femoral artery,
■
1
13282_ON-17.qxd
2
3/22/09
10:45 AM
Page 2
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
Ureter
The ureter originates from the renal pelvis at the level of L1
and courses in the retroperitoneum to the medial surface of the
psoas major muscle, crossed by spermatic or ovarian vessels.
The ureter crosses from lateral to medial on the surface of the
peritoneum at the level of the common iliac bifurcation. This
is a good landmark to identify the ureter during the initial
retroperitoneal dissection. The ureter then courses medially at
the level of the sciatic notch to insert into the trigone of the
bladder.
■
Corona Mortis
The corona mortis is an anastomosis of the external iliac, inferior epigastric, and obturator vessels located in the retropubic region approximately 3 cm from the symphysis pubis.
Laceration during an ilioinguinal approach can lead to extensive bleeding. The retroperitoneal space between pubis and
bladder is called the space of Retzius.
■
Inguinal Canal
The anatomic confines of the inguinal canal are described as
4 cm from the deep inguinal ring to the subcutaneous ring.
This “deep ring” is the “direct” inguinal space originating lateral to the epigastric vessels. Hesselbach’s triangle is the “indirect” hernia space originating medial to the epigastric vessels.
■ The inguinal contents vary by gender:
■ In males, the spermatic cord contains the ductus deferens,
testicular artery, pampiniform plexus, lymphatics, autonomic nerves, the ilioinguinal and genital branches of the
genitofemoral nerve, the cremasteric artery and muscle, and
the internal spermatic fascia.
■ In females, the inguinal contents include the round ligament and the ilioinguinal nerve.
■ The anterior inguinal wall is formed by the aponeurosis of
the external oblique and internal oblique (lateral) muscles.
■ The posterior inguinal wall runs medial to lateral and is
formed by the reflected inguinal ligament, the inguinal falx,
and the tranversalis fascia.
■ The superior or cephalic inguinal wall is formed by
arched fibers of the internal oblique muscle and the transverse muscle of the abdomen.
■ The inferior or caudal inguinal wall is formed by the inguinal and lacunar ligaments.
■
FIG 1 • The bony pelvis and its relation to the major blood vessels, nerves, and visceral organs. (Courtesy of Martin M. Malawer.)
into the femoral triangle, where it is a useful landmark in identifying neighboring structures.
Internal Iliac Artery
The internal iliac (hypogastric) artery descends from the
lumbosacral articulation to the greater sciatic notch and
branches into several arteries. The internal iliac artery and vein
often are difficult to identify or ligate. The internal iliac artery
lies on top of its vein, which often is large and is easily injured.
The hypogastric vessels are routinely ligated in performing
modified hemipelvectomies as well as many pelvic resections.
■
ANTERIOR BRANCHES
The obturator artery exits the pelvis via the obturator canal
(beneath the superior pubic ramus).
■ The inferior gluteal artery curves posteriorly between the
first and second or second and third sacral nerves, then runs
between the piriformis and coccygeus muscles or through the
greater sciatic foramen into the gluteal region below the piriformis muscle.
■
POSTERIOR BRANCHES
The iliolumbar artery ascends posterior to the obturator
nerve and external iliac vessels to the medial border of the
psoas. It then divides into the lumbar branch, to the psoas and
quadratus lumborum muscles and to the spinal cord, and an
iliac branch, to the iliac, gluteal, and abdominal musculature.
The iliac branch often is ligated during surgery.
■ The superior gluteal artery runs posteriorly between the lumbosacral trunk and first sacral nerve and leaves the pelvis
through the greater sciatic foramen superior and posterior to the
piriformis muscle. Great care must be taken to preserve the
gluteal vessels and nerves when performing types 1 and 2 pelvic
resections.
■
Boundaries
Sciatic Notch
The sciatic notch should be identified early in surgery, both
internally and externally, to protect the sciatic nerve and
gluteal pedicles.
■
Osseous Boundaries
The superior cephalad margin of the pelvis is defined by the
ilium and the rim of the great sciatic notch.
■
Posterior Margin
The posterior margin of the pelvis is bounded by the piriformis muscle and the superior gluteal vessels and nerve.
Posterior to the piriformis muscle, the internal pudendal
vessels and nerve course medially off the sciatic nerve and
the posterior femoral cutaneous nerve, anterior to the
piriformis.
■
13282_ON-17.qxd
3/22/09
10:45 AM
Page 3
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
They often are much larger than plain radiographs indicate. Further imaging with CT and MRI often demonstrates
a very large myxomatous component.
Inferior Margin
■
The sacrospinous and sactrotuberous ligaments are released
during type 1 and 2 pelvic resections.
■
Metastatic Adenocarcinoma: Breast, Prostate, Renal,
Lung, Colon
INDICATIONS
Recurrent Benign Tumors
Primary Malignant Osseous Tumors
■
■
Metastatic adenocarcinoma most commonly involves iliac
or periacetabular sites. Most metastatic tumors to the pelvis
are treated adequately with radiation therapy.
■ Occasionally, there may be significant acetabular destruction with an impending pathological fracture that requires surgical reconstruction.
■ Renal cell carcinoma (hypernephroma) metastases are an
exception. These metastases often require surgical removal, either by resection or by curettage and cryosurgery. Preoperative
embolization always is required for these vascular tumors to
avoid severe bleeding during surgery.
■
Major pelvic resections rarely are performed for benign
bony tumors. Occasionally, following multiple recurrence or
when tumors are limited to either the superior or inferior
pubic rami, pelvic resection is indicated.
■ Such benign tumors include large osteochondromas or any
osteochondroma associated with multiple hereditary exostosis, due to the high risk of secondary chondrosarcoma.
■ Osteoblastoma occuring in the ilium or periacetabulum
■ Giant cell tumors or aneurysmal bone cysts have a predilection for the superior pubic ramus and supra-acetabulum.
■
■
3
Osteosarcoma
■ Five percent of all osteosarcomas occur in the pelvis.
Partial pelvic resection or hemipelvectomy (amputation) is
required, usually following induction chemotherapy.
Ewing sarcoma
■ About 25% of all Ewing sarcomas occur in the pelvis.
Surgical resection is required.
■ Radiation therapy remains controversial in treating pelvic
Ewing sarcoma.
■ Resection should be performed only following induction
chemotherapy.
Chondrosarcoma
■ Chondrosarcomas are the most common primary malignant bony tumors of the pelvis.
A
Soft Tissue Sarcomas
Retroperitoneal soft tissue sarcomas are more common than
intraperitoneal sarcomas and must be evaluated for gastrointestinal, genitouretal, vascular or peripheral nerve involvement.
■
IMAGING AND OTHER STAGING
STUDIES
Plain Radiography
Plain radiography (FIG 2) is of limited value in the assessment of pelvic girdle lesions. Images often are obscure and
confusing.
■ The pelvis, particularly the sacrum, is a difficult structure
in which to recognize early bone lesions, and major bone lesions initially may be overlooked. For these reasons, there
■
B
C
D
E
FIG 2 • A. Plain radiographs revealing a large lytic lesion of the
right periacetabular region. On the basis of this radiograph, it appears that the cortices are intact. B. Anteroposterior plain radiograph of the pelvis, read as normal. C. Plain radiographs revealing a cartilage-forming lesion in the left ilium. On the basis of
this study alone, it seems that this is an intraosseous lesion. Plain
radiographs performed 24 hours after a CT-guided core needle
biopsy of a sacral lesion (note the coil) (D) and after 6 weeks (E).
13282_ON-17.qxd
4
3/22/09
10:45 AM
Page 4
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
A
C
B
FIG 3 • A. CT showed extensive bone destruction and extension of the tumor to the pelvis and the right
gluteal region. B. CT of the pelvis revealed a large destructive lesion of the sacrum. C. CT shows an
extensive tumor on the medial aspect of the ilium with destruction of the inner table and extension of the
pelvis. (A,B: Courtesy of Martin M. Malawer; C: Reprinted with permission from Cancer: Principles and
Practice of Oncology, 5th ed. Philadelphia: Lippincott Williams & Wilkins, 1997;38.3:1789–1852.)
should be a low threshold for performing further imaging, especially for initial screening and the postoperative evaluation
of reconstructions.
CT and MRI
CT with intravenous contrast and three-dimensional reconstruction is the optimal technique for assessing the extent of
bone involvement and destruction, the osseous anatomy, and
the relation between the tumor and the major blood vessels
of the pelvis (FIG 3). It is valuable for depicting any distortion
of the pelvic anatomy, and aiding in the evaluation of the
tumor to decide whether it is resectable. Chest CT is essential
for staging purposes in evaluation for pulmonary metastases.
■ MRI with constrast is critical for imaging soft tissue (ie, vessels, nerve, muscle) and osseous involvement. MRI is the optimal modality for imaging soft tissue and marrow involvement.
It is attractive for assessment of osseous disease and sacral involvement, and may be helpful with the serial assessment of
neoadjuvant (induction) therapy.
■
and osteosarcomas. Their presence may change the planned
surgical approach.
FDG-PET
Fluorine-18 2-fluoro-2-deoxy-D-glucose-positron emission
tomography (FDG-PET) may be useful in assessing the
“grade” of malignancy, evaluating response to neoadjuvant
chemotherapy, and monitoring for local recurrence. Positron
emission tomography (PET) combined with CT or MR is useful for “co-registered” imaging. PET CT scans are useful in
early detection of small recurrences. It plays only a minimal
role in preoperative planning in determining the extent of surgical resection.
■
Biopsy
The purpose of biopsy is to yield a valid tumor diagnosis
(benign vs. malignant), tumor grade (high vs. low grade), and
■
Bone Scan
Three-phase bone scan is used to rule out systemic metastasis and to assess the focal osseous involvement and tumor vascularity in the initial flow phase. A decrease in vascularity after
induction chemotherapy may indicate response to treatment.
■
Angiography
Angiography is mandatory for determining the vascular
anatomy that often is distorted by large pelvic tumors (FIG 4).
It is essential to determine the level of the various bifurcations
preoperatively and to rule out vascular involvement by the
tumor. Embolization of the tumor blood supply before surgery
is helpful in minimizing blood loss, especially with vascular tumors and tumors with sacral involvement.
■
Venography
The pelvic veins always are much larger than their arterial
counterparts. Preoperative venography is used to rule out
tumor (mural) thrombi, a common finding in chondrosarcomas
■
FIG 4 • Preoperative angiography and embolization of the
metastatic lesion shown in Fig 3A. (Courtesy of Martin M.
Malawer.)
13282_ON-17.qxd
3/22/09
10:45 AM
Page 5
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
tumor subtype (eg, leiomyosarcoma vs. malignant fibrous
histiocytoma).
■ Biopsies may be performed by either open or needle
technique.
■ Because open biopsy for pelvic tumors is an extensive procedure, needle biopsy—especially CT-guided needle biopsy—
always is performed initially for both metastatic and primary
pelvic tumors.
■ Biopsy technique should follow established guidelines for incision placement within the line of eventual resection, minimize contamination of normal tissues (eg, achieve adequate
hemostasis at biopsy closure), and retrieve an adequate specimen for frozen section diagnosis. The biopsy should avoid the
gluteal and groin areas, because they are potential sources for
flaps for skin closure after anterior and posterior hemipelvectomy, if necessary.
■ Use of the utilitarian surgical incision for open biopsy is
recommended.
Anatomic Considerations
Evaluation of the full anatomic extent of a pelvic tumor cannot be based on a single imaging modality. Combined data,
gained from two or more imaging modalities, allow a realistic
appreciation of the exact anatomic extent. Even when that information is available, however, the full extent of a pelvic
tumor often is underestimated preoperatively.
■ Review of any imaging study of the pelvis, because of the
numerous anatomic details, must be performed very methodically. The authors review the structures from the back (midsacral region) and follow the pelvic girdle to the front (symphysis pubis), as described in the following paragraphs.
■
Sacrum, Sacral Alae, and Sacroiliac Joint
Most patients who undergo extended hemipelvectomy,
which necessitates transection of the sacrum through the ipsilateral neural foramina, regain function of the gastrointestinal
and genitourinary tracts. Adding a contralateral compromise of
the sacral nerve root will create a severe dysfunction. Tumors
that penetrate the sacrum and cross the midline are considered
unresectable because of the involvement of bilateral nerve roots
(FIG 5). The tumor can be resected, but the morbidity outweighs the questionable oncologic benefit from surgery.
■ The common iliac vessels are just anterior to the sacral ala,
and any cortical breakthrough by a tumor in that site may be
■
5
expected to extend directly to the blood vessels. The sacroiliac
(SI) joint is a key anatomic landmark. The major nerves and
blood vessels are medial to it; therefore, any tumor or pelvic
resection lateral to the SI joint may be expected not to violate
the major neurovascular bundle. Involvement of the SI joint
must be documented prior to surgery by using the combination of CT, MRI, and bone scan.
Major Pelvic Blood Vessels and Structures
The common iliac artery bifurcates along the sacral ala, and
the ureter crosses the bifurcation on each side. Large tumors
around the sacral ala commonly displace and occasionally invade these structures. The mere presence of a major blood vessel or a pelvic viscus involvement is not an indicator of unresectability. Direct tumor involvement is rare. If necessary and
curative resection is planned, both structures can be excised en
bloc with the tumor and then can be repaired with a graft.
However, when a compound resection (bony pelvis and viscus
resection) is anticipated, the patient must be informed, and
surgical assistance and necessary equipment must be prepared
in advance.
■
Sacral Plexus
Current imaging techniques cannot accurately identify
nerves. Nerve involvement, therefore, is assumed on the basis
of the pain pattern, physical examination, and the presence of
the tumor in close proximity to a site in which a major nerve
or plexus is usually located. Clinical evidence of femoral or sciatic nerve dysfunction usually means direct tumor involvement. In most cases the presence and extent of nerve involvement is established only at the time of surgery. Sacral plexus
invasion by tumor has the same significance in terms of resectability as tumor invasion of the sacrum; bilateral involvement is an indicator of unresectability.
■
Sciatic Notch and Nerve
The sciatic notch is the site of pelvic osteotomy in resections
of the ilium or periacetabular region and in modified
hemipelvectomy. CT establishes tumor extension to the sciatic
notch, a tight space through which the sciatic nerve and superior gluteal vessels and nerve pass (FIG 6). The piriformis muscle, which divides the sciatic notch, is a key structure, because
the sciatic nerve exits the pelvis underneath it and the superior
gluteal artery exits the pelvis above it. The patency of the superior and inferior gluteal arteries, which supply the gluteal
vasculature, is established by angiography. Adequate blood
supply of the gluteal region is a major consideration in flap design, and the artery must be preserved in any pelvic resection,
if oncologically feasible. The artery is located only a few millimeters from the periosteum of the sciatic notch roof, and it
should be dissected carefully.
■
Ilium
The inner aspect of the bone is covered by the iliacus muscle,
which originates from the iliac crest. The iliacus is “pushed” by
a growing bone sarcoma and serves as a major barrier to direct
extension of tumor to the anatomic structures of the pelvis.
Therefore, the iliacus can be used as a safe oncologic margin for
resection. In contrast, metastatic carcinomas to the pelvis tend
to invade the covering muscle layer in their early growth stage,
and a surgical plane between the tumor and nearby structures
cannot be easily defined (FIG 7). Although any pelvic organ
■
FIG 5 • High-grade chondrosarcoma of the right sacrum, ilium,
and periacetabular region, encasing the ipsilateral sacral foramina. Wide excision would necessitate resection through the contralateral sacral foramina, resulting in an unacceptable functional impairment. (Courtesy of Martin M. Malawer.)
13282_ON-17.qxd
6
3/22/09
10:46 AM
Page 6
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
A
FIG 6 • The sciatic notch is a tight space through which the sciatic nerve and superior and inferior gluteal vessels and nerves
pass. The sciatic nerve exits the notch underneath the piriformis
muscle, and the superior gluteal vessels exit the notch above it.
(Courtesy of Martin M. Malawer.)
can be infiltrated by a tumor, structures that are anterior and
posterior to the flare of the muscle (ie, sacral plexus, sciatic
notch and nerve, femoral vessels and nerve, bladder, and
prostate) are at greater risk for direct tumor extension.
Extension to Pelvic Viscera
Direct involvement of a pelvic viscus by a pelvic girdle
tumor is rare. Left-sided tumors are more likely to involve a
component of the gastrointestinal tract because of its close
proximity to the pelvic girdle at that point. A rectal tube is inserted preoperatively during any pelvic resection to facilitate
identification of the rectum during dissection.
■
Acetabulum and Hip Joint
Wide resection of any bone tumor in the periacetabular region, unlike a resection of the ilium or the pubis, imposes a
major impairment on the function of the hip joint. It usually
necessitates en bloc resection of the proximal femur and a
complex prosthetic reconstruction.
■
Pubis
The neurovascular bundle passes within the femoral triangle
just anterior to the superior pubic ramus. Tumors extending to
or arising from the pubic ramus are in close proximity to the
femoral artery, vein, and nerve. In addition, the urethra passes
straight underneath the symphysis pubis. Vulnerable structures such as a major blood vessel, nerve, or a viscus must be
identified and mobilized before resection. By identifying and
isolating crucial srtuctures, the surgeon avoids iatrogenic injury during dissection. Establishing the relation of these vulnerable structures to the tumor allows the surgeon to decide
whether to proceed with a limb-sparing procedure or perform
an amputation, make the necessary preparations for a vascular graft (if needed), and perform a safe resection.
■
B
FIG 7 • A. The iliacus muscle (arrows) is “pushed” by a growing
bone sarcoma and serves as a barrier to direct extension of the
tumor to the pelvic viscera. High-grade sarcoma of the left ilium
“pushing” the iliacus muscle (arrows) toward the midline.
B. Metastatic carcinomas (arrows) to the pelvis tend to invade
the covering muscle layer. (Courtesy of Martin M. Malawer.)
SURGICAL MANAGEMENT
Preoperative Planning
Restaging studies
Preoperative planning is crucial to obtain an optimal oncologic and functional surgical result.
■ Imaging studies are crucial in addressing the following
questions: location and extent of the tumor, the type of pelvic
resection that is necessary for adequate removal of the tumor,
involvement of critical adjacent structures in the tumor mass
(ie, ureter, aorta, inferior vena cava, bladder), and the type of
reconstruction that can be achieved.
■ Plain radiographs, CT scans, MRI scans, bone scans, and
3D-CT angiographs are obtained to access the extent of osseous and soft tissue involvement in all anatomic planes.
The status of crucial adjacent structures—bladder, colon,
ureter, inferior vena cava, sacral alar, and possible lumbar
extent—is reviewed.
■ Using angiography and venography, preoperative embolization is considered, and anatomic distortion and vessel
occlusion and venous thrombus are assessed.
■ Consider possible need for prophylactic ureteral stents if
there is evidence of preoperative ureteral obstruction or
displacement.
■ Medical and anesthesia personnel are consulted to assess medical risk, preoperative laboratory studies, and transfusion needs
(eg, prepare red blood cell count, cryo, platelets, and plasma). A
risk of major blood loss during surgery is assumed, often equal
to one total body transfusion ( 7% body weight in kg).
■ Bowel preparation before surgery and ICU reservation also
should be considered.
■
13282_ON-17.qxd
3/22/09
10:46 AM
Page 7
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
Orthotic brace is fabricated preoperatively for postoperative
use.
■ Colostomy planning and training must be considered if there
is left colon involvement, or large left-sided pelvic tumors, both
of which can be detected preoperatively with contrast-enhanced
CT and colonoscopy.
■ Appropriate prosthetic implants (eg, total hip replacement
vs. saddle prosthesis), bone allograft, or other implants must
be ordered.
■
Positioning
At the time of surgery all patients should have a Foley
catheter and a rectal tube placed. The rectum is sutured
■
closed around the rectal tube to avoid iatrogenic contamination during the operative procedure. During surgery the surgeon may palpate the balloon of the Foley catheter in the
bladder and the rectal tube through the wall of the rectum, to
assist in proper identification of these structures. This is especially helpful with large pelvic tumors, especially those on
the left side.
■ Type 1 resection (iliac ): the patient is positioned in the lateral decubitus position with an anterior tilt to allow posterior
access (FIG 8A–D).
■ Type 2 resection (periacetabular): the patient is positioned
in the lateral decubitus position for access to both the anterior
and posterior pelvis (FIG 8E,F).
A
B
C
D
E
F
G
7
H
FIG 8 • Type 1 pelvic (ilium) resection can be either partial (A), in which only part
of the ilium is transected, or complete (B). Partial (C) and complete (D) type 1 resections. E. Type II pelvic (periacetabular) resections. Reconstruction was performed with a saddle prosthesis. F. Type II pelvic resection. G–I. Type III pelvic
(pubic) resection. These resections may include the superior pubic ramus (G), infeI
rior pubic ramus, or both rami (H). I. Type III pelvic resection.
13282_ON-17.qxd
8
3/22/09
10:46 AM
Page 8
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
hamstrings from the ischium, the lateral margin of the sacrum,
and the entire buttock.
■ The most useful approach to pelvic biopsy or resection is the
utilitarian pelvic incision. All or part of the incision can be
used for adequate exploration and resection of the majority of
pelvic girdle tumors.
■ Significant concern exists regarding the possible extracompartmental implantation of tumor cells following biopsy or
resection of a pelvic tumor, procedures that are difficult to perform under optimal hemostatic conditions. Unnecessary biopsies must, therefore, be avoided. If biopsy is indicated, the
proper technique and a suitable approach must be chosen. The
biopsy tract must be positioned along the line of the future utilitarian incision, remote from the major neurovascular bundle
and the abductors. CT-guided core needle biopsy is considered
to be an accurate and safe diagnostic tool in the diagnosis of
musculoskeletal tumors and is the modality preferred by the
authors. The utilitarian incision may be used for hemipelvectomy by continuing the distal portion of the primary incision
posteriorly around and behind the thigh and bringing it anteriorly along the inferior pubic ramus to the symphysis, thus encircling the thigh but still allowing the large posterior flap to be
used for primary wound closure.
Type 1 Resection: Iliac Resection
The incision for an iliac resection is ilioinguinal, following
the iliac crest and curving posteriorly at the level of the sacroiliac joint. It then follows the length of the sacroiliac joint combined with a lateral incision to expose the outer portion of the
ilium, sciatic notch, and retrogluteal space
■
FIG 9 • The utilitarian pelvic incision. (Courtesy of Martin M.
Malawer.)
Type 2 Resection: Periacetabular Resection
Type 3 resection (pelvic floor): The patient is positioned
supine with the lower extremity flexed and abducted to provide exposure of the retroperitoneal space, the femoral triangle, the perineum, the symphysis pubis, and the ischiorectal
space (FIG 8G–I).
■
Approach
The utilitarian pelvic incision is indicated (FIG 9).
The incision begins at the posterior inferior iliac spine and
extends along the iliac crest to the anterior superior iliac spine.
It is separated into two arms: one is carried along the inguinal
ligament up to the symphysis pubis; the other turns distally
over the anterior thigh for one-third the length of the thigh
and then curves laterally just posterior to the shaft of the
femur below the greater trochanter and follows the insertion
of the gluteus maximus muscle. Reflection of the posterior
gluteus maximus flap exposes the retrogluteal space, the proximal third of the femur, the sciatic notch, the sciatic nerve the
sacrotuberous and sacrospinous ligaments, the origin of the
■
TECHNIQUES
■
A combination of an anterior retroperitoneal approach and
lateral anterior incision along the femur that curves posteriorly
is used for a periacetabular resection. A lateral, posterior-based
fasciocutaneus flap, called a gluteal flap, is then raised. This
permits easy access and visualization of the retrogluteal space;
hip joint, sciatic notch, sciatic nerve, and ischium, as well as
the supra-acetabular area needed for the superior osteotomy.
■
Type 3 Resection: Pelvic Floor and Pubic Region
Three incisions are required for a resection of the pelvic
floor and pubic region. The main incision is the retroperitoneal (ilioinguinal) incision to permit retroperitoneal exploration and mobilization of the major vessels and nerves.Two
longitudinal incisions are required to develop a distal-based
flap of the anterior thigh so as to expose the femoral triangle
as well as the adductors attaching to the obturator foramen.
One incision follows the perineal crease; the second begins at
the lateral portion of the ilioinguinal incision at the level of the
anterior superior iliac spine.
■
Type 1: Iliac Resection
■
■
■
The patient is placed in the lateral decubitus position
with a posterior tilt.
The utilitarian pelvic incision is used. Its ilioinguinal component is advanced medially to the symphysis pubis, and
its posterior arm is brought to the level of the sacroiliac
joint (TECH FIG 1A,B).
All muscle attachments, with the exception of the iliacus
and gluteus minimus and portions of the gluteus medius,
which are resected en bloc with the tumor, are removed
from the iliac crest. The abdominal wall musculature, the
sartorius muscle, and the tensor fasciae latae muscle are
transected from the iliac crest and reflected away from
the ilium. The rectus femoris muscle remains intact. The
iliotibial band is transected from its origin from the iliac
crest and reflected posteriorly along with the gluteus
maximus. Large fasciocutaneous flaps are raised and reflected medially and posteriorly.
13282_ON-17.qxd
3/22/09
10:46 AM
Page 9
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
9
TECHNIQUES
B
A
C
D
TECH FIG 1 • A. Incision and surgical approach. The entire utilitarian incision is used for type I resection. The posterior fasciocutaneous flap exposes the entire retrogluteal area: the sciatic notch, the sciatic nerve, the abductor muscles, and the hip joint. This
approach provides a good exposure of the retroperitoneal space as well as the posterior retrogluteal area and permits a safe resection of the ilium. The ilioinguinal component is advanced medially to the symphysis pubis and posteriorly to the sacrum (B).
C. Posterior exposure and muscle releases. The abdominal wall musculature is transected off of the iliac crest. The sartorius and
tensor fascia lata muscles are transected from their tendinous insertions and reflected distally. The rectus femoris muscle remains
intact. Large fasciocutaneous flaps are raised and reflected medially and posteriorly. The iliotibial band is transected from its origin from the iliac crest and reflected posteriorly along with the gluteus maximus. D. Anterior (retroperitoneal) exposure. The
retroperitoneal space is easily exposed and explored through the ilioinguinal component of the incision. The plane between
the iliacus and the psoas muscle is developed with caution, because the femoral nerve lies in that space. The psoas muscle and
the femoral nerve are reflected medially, and the iliacus muscle is transected through its substance. The femoral nerve is preserved. (continued)
13282_ON-17.qxd
10
3/22/09
10:46 AM
Page 10
TECHNIQUES
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
E
F
G
TECH FIG 1 • (continued) E. Posterior exposure and release of
gluteal muscles. The retrogluteal area is exposed. The gluteus
maximus muscle is released from the iliotibial band and from the
femur and reflected posteriorly. The sciatic nerve is identified
and preserved. All of the remaining abdominal muscles are released from the wing of the ilium. The gluteus medius muscle is
transected through its substance, 2 to 3 cm distal to the inferior
border of the tumor. It is important to try to save as much muscle belly as possible. F. Supra-acetabular osteotomy and sacroiliac disarticulation. A malleable retractor is inserted through the
greater sciatic notch, along the inferior border of the inner table,
and out just underneath the anterior superior iliac spine, to protect the pelvic viscera. The ilium is transected above the hip capsule, leaving the origin of the rectus femoris muscle and the roof
of the acetabulum intact. Care is taken not to enter the hip joint.
Insert: The sacroiliac joint is opened from within the pelvis. The
iliac vessels must be mobilized and retracted before attempting
to open the sacroiliac joint. G. Soft tissue reconstruction. The gluteus medius muscle is sutured to the abdominal wall musculature
with the ipsilateral lower extremity in abduction. Dacron tape
must be used to reinforce this reconstruction. The suture line also
is reinforced by oversewing the tensor fascia lata and sartorius
muscles. (Courtesy of Martin M. Malawer.)
■
■
The plane between the iliacus and the psoas muscle is developed cautiously, because the femoral nerve lies in
that space. The psoas muscle and the femoral nerve are
reflected medially, and the iliacus muscle is transected
through its substance (TECH FIG 1C).
The external iliac artery, which lies against the lower margin of the ilium, gives off no major branches along the
inner table of the ilium; ligation of large blood vessels is
not required, therefore, in type I pelvic resection. Most
tumors of the ilium break through the outer table and
push the gluteus medius muscle laterally. The gluteus
medius muscle is transected through its substance, 2 to
3 cm distal to the inferior border of the tumor (TECH FIG
1D,E). It is important to try to save as much muscle belly
as possible because that will be the major component in
soft tissue coverage of the pelvic content and will be necessary for reconstruction of the abductor mechanism.
■
■
Osteotomy of the ilium is performed using a malleable
retractor, which is inserted through the greater sciatic
notch, along the inferior border of the inner table, and
out just underneath the anterior superior iliac spine, to
protect the pelvic viscera (TECH FIG 1F). The ilium is
transected as shown by the dotted line in the figure,
leaving the origin of the rectus femoris muscle and the
roof of the acetabulum intact. Osteotomy of the posterior aspect of the ilium is then performed; a malleable retractor is positioned through the greater sciatic notch,
along the posterior border of the ilium, and parallel to
the ipsilateral sacral ala (insert, Tech Fig 1F).
The most important component of soft tissue reconstruction is the attachment of the proximal rim of the gluteus
medius muscle to the abdominal wall musculature. Even
if the entire gluteus medius muscle was spared, the attachment of these two muscle groups, which are not
13282_ON-17.qxd
3/22/09
10:46 AM
Page 11
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
■
■
Optional Reconstruction
■
■
■
■
It is not necessary to reconstruct the resultant bony defect, although allograft reconstruction has been reported.
For iliac osseous reconstruction, allograft should be
thawed with permanent/tissue culture. Gram stain has a
high rate of false positives and should be avoided.
Cut the allograft after careful sizing and orientation and
fix with a 4.5-mm reconstruction plate. Use intraoperative radiographs to confirm screw placement.
Two deep soft drains (anterior and posterior) are placed
deep to the fascial closure.
Type 2: Periacetabular Resection
■
■
The patient is in the lateral decubitus position with posterior tilt to maximize anterior dissection.
The utilitarian incision is used to expose both the anterior (internal) and posterior (extrapelvic) aspects of the
pelvis. The ilioinguinal incision is used to develop the
retroperitoneal plane, and the posterior gluteus max-
■
■
■
imus fasciocutaneous flap is used to develop the retrogluteal space.
The iliac vessels are mobilized first, and the hypogastric
artery is identified and ligated. The sciatic and femoral
nerves are identified and protected.
The level of osteotomy through the ilium is identified
from within the pelvis, as are the superior pubic rami.
Identification of the superior pubic rami requires mobilization of the external iliac and femoral vessels as they
cross the ramus (TECH FIG 2).
A large posterior myocutaneous flap is developed with
the gluteus maximus muscle. The gluteus maximus muscle
is detached from the iliotibial band and femur to enable
it to be retracted posteriorly. This exposes the retrogluteal
space: the ilium, sciatic notch, sciatic nerve, and hip joint.
The ischium is identified through the posterior incision
and is osteotomized above the level of the biceps
femoris tendon insertion.
Complete removal of the periacetabulum requires release of the sacrospinous ligament and some of the
pelvic floor musculature. An ilioinguinal incision is used
with a separate posterolateral hip incision for hip exposure and replacement, posterior column osteotomy, and
exposure of the sciatic nerve.
■
Three types of osteotomies may be used for periacetabular resection: (1) supra-acetabular osteotomy;
(2) superior pubic ramus osteotomy; and (3) ischial
osteotomy.
A
D
B
C
E
F
TECH FIG 2 • A. Plain radiograph showing an extremely high-grade malignant fibrous histiocytoma arising from the superior and inferior pubic ramus involving the entire obturator foramen, pelvic floor, and
medial and supra-acetabular aspect of the acetabulum (solid arrows). B. Gross specimen following type
II/type III pelvic resection. C. Gross specimen following a complete internal hemipelvectomy (type I/type
II/type III pelvic resection). D. Radiograph of the resected specimen showing complete involvement of
the hemipelvis. The defect superiorly was created by an open biopsy. E. Gross specimen of a combination type II/type III pelvic resection. F. Gross specimen following a type III pelvic resection. A large tumor
mass is seen arising from the obturator internus muscle (solid arrows). A, acetabulum; IL, portion of the
ilium; IP, inferior pubic ramus and pubis; P, the entire pelvic floor, including the superior and inferior
pubic ramus; SP, superior pubic ramus; SY, symphysis pubis. (Courtesy of Martin M. Malawer.)
TECHNIQUES
anatomically connected, creates a significant tension,
which can be reduced by placing the lower extremity in
abduction. The suture line is reinforced with the tensor
fasciae lata and sartorius muscles with 3-mm Dacron tape
(TECH FIG 1G). Closure of the muscle layer must be
meticulous, because poor healing and wound dehiscence
will expose the abdominal and pelvic contents and will
be difficult to manage.
11
13282_ON-17.qxd
TECHNIQUES
12
3/22/09
10:46 AM
Page 12
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
■
■
■
■
A total hip exposure is used to identify the sciatic nerve
and posterior column. The procedure is begun with dissection of the external rotators and osteotomy of the
femoral neck, per total hip procedure.
Cut the femoral neck at the standard neck length (1.0 cm
proximal to the lesser trochanter).
Incise the hip capsule peripherally with dissection of the
sciatic nerve proximally to the sciatic notch.
The anterior and posterior columns are exposed to allow
osteotomy of the acetabulum. Posterior column osteomy
requires careful exposure and retraction of the sciatic
nerve and gluteal vessels.
plug is inserted to a depth of 2 cm below the tip of the
selected femoral stem. The femoral canal then is irrigated
with saline and packed with gauze. Once the cement
(polymethylmethacrylate) is prepared, the gauze is removed, and the femoral prosthesis is cemented within
the proximal femur.
Trial Reduction
■
Reconstruction After Type 2
Resection
■
Several choices are available for reconstruction following a type 2 resection: composite allograft; saddle reconstruction (Link, America); partial pelvic prosthesis
(Stryker, Mahwah, NJ); various reconstruction rings with
large phlanges; and ischiofemoral arthrodesis. Each has
unique techniques, complications, functional deficits,
and results.
■
Composite Allograft Acetabular
Reconstruction
■
■
■
■
Femoral component: ream and place the uncemented
femoral component through the posterior lateral approach before proceeding with iliac osteotomy resection.
Acetabulum: ream the allograft for the acetabular component and place the acetabular component (cement
and screws) into the allograft to confirm graft and acetabular orientation in situ with radiography before
screw or cement fixation.
Check acetabulum positioning with radiographs before
and after fixation or cementation. Orient the iliac graft
before confirming the acetabular orientation, and fix
the graft with a reconstruction plate and screws. Use an
extended polyethylene acetabular rim and consider a
large femoral head (32–36 mm) to improve postoperative stability.
Closure. Using the inguinal ligaments, reconstruct the
abductors, especially if a trochanteric osteotomy was
done. Perform pelvic closure at the iliac crest and inguinal canal with wound drainage catheters.
Abductor Mechanism Reconstruction
■
■
Type 2: Resection and Reconstruction
with Saddle Prosthesis
Notchplasty (Tech Fig 3A–C)
■
A notch is created in the remaining ilium using a highspeed burr. The notch should be placed in the thickest region of the remaining bone (usually medial).
Preparation of the Proximal Femur
■
The proximal femur is prepared as for a standard femoral
component. The intramedullary canal of the proximal
femur is reamed to accept the largest-diameter stem and
allow for a 2-mm circumferential cement mantle. Once
reaming is completed, and the appropriate-sized stem
(diameter and length) is selected, a distal femoral cement
A reduction using trial components is critical in assessing
accurate length of the base component (intercalary segment) and determining optimum soft tissue tension
(TECH FIG 3D–K). The base component length should
be determined by the distance between the ilium and
femoral neck cuts, because the length indicated on the
base component is the total length from the notch of
the saddle to the femoral collar. The base component
should be selected so that reduction is barely possible
and there is minimum “play” in the reduced joint. The
surgeon should be able to reattach the abductor mechanism to its anatomic position on the osteotomized
greater trochanter.
A trial reduction also can determine areas where the saddle component may impinge on the existing notch during intraoperative range of motion. These areas can be
further contoured with a high-speed burr to prevent impingement, which may result in limited motion or dislocation. Hip motion (flexion to at least 90 degrees, extension to 30 degrees, abduction to 45 degrees, adduction
to neutral, and rotation) should be possible without evidence of impingement or dislocation.
■
The osteotomized greater trochanter and abductors are
reattached to their original location using cables. If the
greater trochanter was included in the resected specimen, the abductor mechanism is reattached to the prosthesis using 3-mm Dacron tapes or a cable system. Soft
tissue tension and prosthetic stability are again tested
once the abductor mechanism reconstruction is complete. The piriformis and short external rotator muscles
are brought forward and reattached to the proximal
femur (or prosthesis). The gluteus maximus muscle is
then reattached to its insertion using nonabsorbable
suture (TECH FIG 3L–N).
Pelvic closure involves attachment of the inguinal canal
and abdominal wall to the symphysis pubis and lateral
iliac crest. Soft tissue tension and prosthetic stability are
tested again once the abductor mechanism reconstruction is complete. The piriformis and short external rotator muscles are brought forward and reattached to the
proximal femur (or prosthesis). The gluteus maximus
is then reattached to its insertion using nonabsorbable
suture.
For high type II pelvic resections, reconstruction should
be carried out with a partial pelvic prosthesis (Stryker,
Mahwah, NJ).
Type 3 Resection: Pelvic Floor
■
A utilitarian pelvic incision with a perineal extension is
used (three-incision approach).
13282_ON-17.qxd
3/22/09
10:46 AM
Page 13
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
C
B
E
D
G
F
TECH FIG 3 • A. Photograph following a periacetabular resection showing the remaining ilium (il), the sciatic nerve (S), the
greater trochanteric osteotomy (G), and the femoral head.
B. Intraoperative photograph demonstrating the creation of
the deep notch (large arrows). C. Reduction of the saddle
prosthesis into the iliac notch (IL). The notch (solid arrows)
must be as deep as the saddle and permit approximately
45 degrees of flexion and extension, as well as abduction and
adduction. D. Surgical exposure using the utilitarian pelvic incision. E. A large posterior fasciocutaneous flap based medially permits the release of the gluteus maximus. F. Schematic
diagram of the mobilization of the periacetabular structures
and the three osteotomies that are necessary for a complete resection of the acetabulum. G. Schematic of the “close-up” view
of the superior pubic ramus osteotomy. (continued)
TECHNIQUES
A
13
13282_ON-17.qxd
14
3/22/09
10:46 AM
Page 14
TECHNIQUES
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
H
I
K
L
J
M
TECH FIG 3 • (continued) H. Schematic diagram of the infra-acetabular osteotomy.
I. A notch is made in the supra-acetabular roof or remaining ilium for the saddle
prosthesis to sit in. J. Schematic diagram of the saddle prosthesis reduced into the
notch. K. Schematic diagram of the saddle prosthesis following a periacetabular
resection for sarcoma and radical curettage for a large acetabular metastasis.
Postoperative radiographs and CT scans demonstrating common postoperative radiographic findings. L. AP radiograph of the pelvis with a saddle prosthesis in
place. M. A 45-degree oblique radiograph of the affected side of the pelvis. N. CT
scan showing a typical saddle prosthesis in good position. AB, abductor muscles; G,
gluteal muscles; IC, iliacus muscle; S, sciatic nerve. (A–C, L–N: Courtesy of Martin
M. Malawer; D–K, reprinted with permission from Malawer M. Reconstruction following resection of primary periacetabular tumors. Semin Arthroplasty 1999;10:
171–179.)
N
■
■
■
■
The patient is positioned with the ipsilateral hip slightly
elevated.
The ilioinguinal component of the utilitarian pelvic incision with a lateral and perineal (medial) extension is
used (see Tech Fig 1G). This incision allows exposure and
mobilization of the femoral vessels and nerve through a
distal-based anterior flap.
Perineal extension of the incision is used to expose the ischium, which is resected through the ischiorectal fossa
when the resection is performed for a large pubic lesion.
Large myocutaneous flaps are raised. The spermatic cord
is reflected medially. The inguinal ligament is transected
from its pubic insertion and reflected laterally.
■
■
■
The neurovascular bundle (ie, the femoral artery, vein,
and nerve) is retracted laterally, exposing the origin of
the adductor magnus and pectineus muscles, which is
transected off the pubis and reflected distally.
Using the lateral component of the incision, the origins
of the hamstrings, adductors, and gracilis are transected
off the ischium and reflected distally (TECH FIG 4).
The first malleable retractor is placed behind the symphysis pubis, in front of the bladder. The second malleable
retractor is placed behind the superior pubic ramus and
in front of the inferior pubic ramus, medial or lateral to
the ischium, depending on the required oncologic margins (TECH FIG 4C).
13282_ON-17.qxd
3/22/09
10:46 AM
Page 15
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
15
TECHNIQUES
A
B
TECH FIG 4 • Incision. A. The ilioinguinal
component of the utilitarian pelvic incision
with a modified perineal extension are
used. B. Schematic of the three osteotomies
required to remove the pelvic floor.
C. Transection of the symphysis pubis, superior pubic ramus, and ischial osteotomy.
(Courtesy of Martin M. Malawer.)
C
■
■
■
■
Osteotomy through the symphysis pubis and pubic
rami is performed. It is important to smooth the sharp
bony edges, especially those that lie against the
bladder.
Surgical wounds around the groin are notoriously associated with a high incidence of dehiscence and infection. Meticulous wound closure with adequate
drainage is, therefore, mandatory. Continuous suction
is required for 3 to 5 days. Perioperative intravenous
antibiotics are continued until the drainage tubes are
removed.
Postoperative mobilization with weight-bearing as tolerated is allowed.
Rarely, reconstruction of the pelvic floor with Marlex (CR
Bard, Cranston, RI) mesh is required.
Type 4 Resection: Hemipelvic
■
■
■
■
■
■
Table 1 describes hemipelvic resection, along with other
techniques.
Combined, extended full pelvic dissection from symphysis pubis to sacroiliac joint is required.
Complete dissection of the sciatic notch, the hip joint,
the sciatic nerve, and the femoral vessels is required.
Pelvic reconstruction is more challenging because of the
need for fixation at the sacrum and symphysis pubis and
the difficulty in orienting a pelvic graft.
Some surgeons do not recommend reconstruction but accept 3 inches of shortening and the use of a pelvic longleg brace.
A large amount of intraoperative blood loss and
hemipelvic graft fixations present significant surgical
challenges.
13282_ON-17.qxd
16
3/22/09
10:46 AM
Page 16
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
Table 1
Summary of Pelvic Resection and Reconstruction Techniques
Surgical
Technique
Position
Incision
Exposure
Vessels
and Nerves
Resection
Reconstruction
Closure
Type 1: Posterior
iliac resection
Lateral with
anterior tilt
Ilioinguinal with
or without sacral
extension
External
oblique and
abdominal m.
Careful dissection
of femoral n. and
vessels; iliac,
gluteal vessels
Iliopsoas,
osteotomy at
iliac crest
Allograft fixation with
4.5-mm plate
Type 2: Lateral
acetabular
resection
Straight
lateral
Ilioinguinal with
separate posterior
lateral hip incision
External
oblique off
superficial
lateral crest
m., expose hip
External iliac a.
and v., obturator
n., gluteal
vessels, sciatic n.
Ream allograft for
acetabular placement;
cement and screw
with 4.5-mm plate
Type 3: Anterior
obturator
Supine
Ilioinguinal
incision with
anterolateral
extension
Symphysis
pubis to
posterior
lateral iliac
crest
Femoral sheath,
lateral femoral
cutaneous n.,
obturator n., a.,
v.
Hip joint,
sciatic notch,
external
rotators,
femoral neck
osteotomy
Between
inferior pubic
ramus and
ischium,
depending on
tumor location
Abdominal wall
m. to pelvis with
nonabsorbable
sutures and two
deep drains
(anterior and
posterior)
Attach inguinal
canal and
abdominal wall
to symphysis
pubis and lateral
iliac crest
Inguinal canal
with
nonabsorbable
sutures and deep
drains; prevent
inguinal hernia
Hemipelvic
Lateral
Ilioinguinal
External iliac
Gluteal
Prone
Posterior gluteal
Symphysis to
lateral crest
and external
iliac m.
Gluteal m.
Retroperitoneal
(soft tissue)
Supine
Symphysis to
posterolateral
ilium
Iliac and gluteal
vessels, ureter,
femoral vessels
and nerve,
sciatic n.
Inguinal groin
Supine
Pubic tubercle to
lateral iliac crest
Midline if
bowel is
involved.
Abdominal/
external
oblique off
iliac crest
Inguinal
ligament,
spermatic
cord,
umbilical
Sciatic n.,
gluteal n., v., a.
Femoral sheath,
inferior epigastric
vessels
Iliac and hip,
with or
without
obturator
Deep proximal
posterior
greater
trochanter, if
inferior to
notch
Usually
respects
iliopsoas
musculature
Inguinal canal
Soft tissue with
Martex/fascia allograft
or Gore-Tex if
acetabular anterior
column intact. If not
intact, then bony
obturator allograft
Allograft verse saddle
prosthesis
External oblique
abdominal wall
reattached to pelvic
brim
Lateral crest and
ilioinguinal canal
Reattach
external oblique
to pelvic brim
Inguinal ligament
PEARLS AND PITFALLS
Vascular problems
■
Always have vascular control of the major vessels proximally and distally, both arterial and venous.
Intraoperative bleeding
■
Severe bleeding usually occurs with venous, not arterial, injuries. Suture and ligate all serious
bleeders.
Thrombosis
■
All patients are at risk to develop an arterial thrombosis during or after surgery and should be
evaluated (pulses) carefully during and for the first 72 hours. Always confirm adequacy of
hemostasis and distal flow and pulses before leaving the operating room. If there is any question,
perform an intraoperative or postoperative angiogram.
Postoperative bleeding
and coagulopathy
■
If bleeding continues, and coagulation factors rule out disseminated intravascular coagulation,
strongly consider taking the patient back to the operating room. Alternatively, perform an
angiogram with attempt at embolization of the bleeding vessel. The degree and timing of the
bleeding are important in determining the correct course of action.
■ If massive ( 4.0–5.0 L) bleeding occurs during the dissection, pack the wound with local pressure
until the patient’s blood pressure stabilizes.
13282_ON-17.qxd
3/22/09
10:46 AM
Page 17
Chapter 17 OVERVIEW ON PELVIC RESECTIONS: SURGICAL CONSIDERATIONS AND CLASSIFICATIONS
17
■
Check prothrombin time, partial thromboplastin time, and platelet counts intraoperatively and
every 6 hours for 24–48 hours.
■ Almost all patients need intensive monitoring following surgery.
Hypocalcemia
and Hypomagnesemia
■
Nerve injuries
■
Ureter and
bladder injuries
■
Hip
■
Check hip radiographically for stability prior to and after wound closure.
General
■
Remember that the first step in avoiding injury to the critical structures mentioned is taking the
time to identify and tag all of them initially during dissection.
Calcium (Ca) always is required intraoperatively. Check the Ca level in the operating room and
postoperatively.
■ Magnesium (Mg) loss is very common following a major bleed, especially in patients treated with
induction chemotherapy. The agent that most commonly causes Mg loss is cisplatinum. Patients
receiving this form of chemotherpay routinely require a large amount of Mg postoperatively. If left
uncorrected, cardiac arrest may occur.
Iatrogenic injury may occur to femoral, sciatic, or sacral nerve roots. Injury occurs during dissection
(neuropraxia) or sacral screw fixation. Obturator nerve sacrifice is not a significant functional loss.
Consider a preoperative ureteral stent for all large tumors. Foley catheter placement enables
palpation of the bladded intraoperatively.
■ Repair bladder wall injuries in two or three layers. Check carefully for bladder injury if hematuria
or oliguria occurs intraoperatively.
POSTOPERATIVE CARE
The distal extremity pulses are checked immediately after
surgery and every hour for the first 24 hours. Late arterial
thrombosis often is due to intimal injuries.
■ Persistent wound drainage usually is due to a large
retroperitoneal collection. If the wound continues to drain
after 4 to 7 days postoperatively, wound irrigation and
drainage in the operating room should be considered.
■ All postoperative patients should have a pelvic radiograph
once a week for the first 2 weeks.
■ Postoperative complete blood cell count and laboratory
studies daily for the first week then twice per week.
■ Postoperative mobilization is highly individualized:
■ Type 1 resection. Abdominal wall to abductors are maintained in abduction for 7 days in bed and then in a
pelvic–thigh brace that avoids excessive adduction.
■ Type 2 resection and reconstruction is very variable.
Patients with a saddle prosthesis and composite allograft are
maintained on partial weight bearing for 3 to 6 months and
need a pelvic and thigh brace for 2 to 3 months.
■ Patients with a type 3 resection with or without Marlex
reconstruction are kept in bed with the lower extremity in
neutral (it is necessary to avoid abduction) to avoid a perineal incision dehisence. A pelvic and thigh orthosis is used
for about 3 months. Full weight bearing can be initiated
early if the medial wall of the acetabulum was not
involved.
■
COMPLICATIONS
Early
Bleeding. Most problems with intraoperative bleeding occur
with venous, not arterial, bleeding. Coagulopathy and the
need for large blood transfusions are common complications.
Coagulation factors, Ca, and Mg should be monitored.
Patients should receive packed cells, fresh frozen plasma,
platelets, Ca, and Mg as necessary during and after surgery.
■ Arterial thrombosis occurs due to intimal flap tear and
should be monitored by distal pulse measurement with
■
Doppler, every hour for the first 24 hours. If arterial thrombosis occurs, immediate thrombectomy is required.
■ Nerve. Postoperative femoral or sciatic neuropraxia are
common and should be observed.
■ Ureter/bladder. Patient should be evaluated for intraoperative hematuria or oliguria, which may suggest bladder or
ureter injury. Urine output is routinely measured hourly during surgery. The Foley urinary catheter is kept in place for 4 to
7 days.
■ Bowel injuries require repair or resection and possible
colostomy.
■ Major ileus is a common problem following extensive pelvic
surgery. The patient should be given nothing by mouth, with
a nasogastric tube in place, until appropriate bowel sounds return (usually 3–4 days).
Late Complications
Infection. Deep infection develops in 20% to 30% of patients following surgery. If such an infection occurs, the patient
must be taken back to the operating room, and the prosthesis
and allograft must be removed, leaving the limb flail.
■ Dislocation. The dislocation rate for a saddle prosthesis is
5% to 10%. This rate may be even higher for “composite”
reconstructions.
■ Failure of the allograft may take the form of fracture
through the allograft or failure of fixation.
■ Prosthesis failure includes failure of the reconstruction ring,
acetabular cup, screws, and plate.
■ Morbidity and mortality after pelvic resection remains high.
Hemipelvectomy may be required due to local recurrence, infection, or uncontrolled bleeding.
■
REFERENCES
1. Aboulafia AJ, Buch R, Mathews J, Li W, Malawer MM.
Reconstruction using the saddle prosthesis following excision of primary and metastatic periacetabular tumors. Clin Orthop Relat Res
1995;(314):203–213.
2. Aljassir F, Beadel GP, Turcotte RE, et al. Outcome after pelvic sarcoma resection reconstructed with saddle prosthesis. Clin Orthop
Relat Res 2005 Sep;(438):36–41.
13282_ON-17.qxd
18
3/22/09
10:46 AM
Page 18
Part 4 ONCOLOGY • Section III SPINE AND PELVIS
3. Cottias P, Jeanrot C, Vinh TS, et al. Complications and functional
evaluation of 17 saddle prostheses for resection of periacetabular tumors. J Surg Oncol 2001;78:90–100.
4. Enneking WF, Dunham WK. Resection and reconstruction for primary neoplasms involving the innominate bone. J Bone Joint Surg
Am 1978;60:731–746.
5. Hillmann A, Hoffmann C, Gosheger G, et al. Tumors of the pelvis:
complications after reconstruction. Arch Orthop Trauma Surg
2003;123:340–344.
6. Ozaki T, Hoffmann C, Hillmann A, et al. Implantation of hemipelvic
prosthesis after resection of sarcoma. Clin Orthop Relat Res 2002
Mar;(396):197–205.
7. Renard AJ, Veth RP, Schreuder HW, et al. The saddle prosthesis in
pelvic primary and secondary musculoskeletal tumors: functional results at several postoperative intervals. Arch Orthop Trauma Surg
2000;120:188–194.
8. Shin KH, Rougraff BT, Simon MA. Oncologic outcomes of primary
bone sarcomas of the pelvis. Clin Orthop Relat Res 1994 Jul;(304):
207–217.
9. Wirbel RJ, Schulte M, Mutschler WE. Surgical treatment of pelvic
sarcomas: oncologic and functional outcome. Clin Orthop Relat Res
2001 Sep;(390):190–205.