12 Fractures of the Pelvis 239 12 Fractures of the Pelvis M. Tile tions, the results with simple treatment will be quite 12.1 different (Fig. 12.1). Therefore, in reading the litera- Introduction ture, we must be certain that we are not comparing apples with oranges or chalk with cheese. An under- In the past two decades, traumatic disruption of the standing of this injury is the key to logical decision pelvic ring has become a major focus of orthopedic making. interest, as has the care of polytraumatized patients. This injury forms part of the spectrum of polytrauma and must be considered a potentially lethal injury with mortality rates of 10%–20%. The stabilization 12.2 of the unstable pelvic ring in the acute resuscita- Understanding the Injury tion of multiply injured patients is now conventional wisdom. In order to better understand our proposed classi- With respect to the long-term results of pelvic fication and rationale of management, some knowl- trauma, conventional orthopedic wisdom held that edge of pelvic biomechanics is essential. surviving patients with disruptions of the pelvic ring The pelvis is a ring structure made up of two recovered well clinically from their musculoskeletal innominate bones and the sacrum. These bones have injury. However, the literature on pelvic trauma was no inherent stability, and the stability of the pelvic ring mostly concerned with life-threatening problems is thus due mainly to its surrounding soft tissues. and paid scant attention to the late musculoskeletal The stabilizing structures of the pelvic ring are the problems reported in a handful of articles published symphysis pubis, the posterior sacroiliac complex, prior to 1980. Despite the clinical impressions that and the pelvic floor. Although the anterior structures most patients do well, some authors have suggested are important, contributing 40% of the stiffness to the otherwise. ring (Hearn et al. 1991), the integrity of the posterior Holdsworth (1948) reported on 50 pelvic fractures sacroiliac complex is most important in maintaining and indicated that of the 27 patients with a sacroiliac pelvic ring stability (see Fig. 12.6). dislocation, 15 had significant pain and were unable to work, whereas those with a sacral or iliac fracture had more satisfactory results. Pennal and Suther- 12.2.1 land (1959), in a large, unpublished study of 359 Ring Structure of the Pelvis cases, further suggested that patients with unstable vertical shear injuries had many late complications. The pelvis is a true ring structure. It is self-evi- Slatis and Huittinen (1972) and Monahan and Taylor dent that if the ring is broken in one area and dis- (1975) both confirmed the significant percentage of placed, then there must be a fracture or dislocation late musculoskeletal problems. in another portion of the ring. Thus the vast litera- In reading the literature, the case mix for each ture describing anterior or posterior pelvic fractures series must be determined; otherwise the conclusions suggesting that they appear in isolation is mislead- may be erroneous. Pelvic fractures must be classified ing. Gertzbein and Chenoweth (1977), in a series of according to their degree of instability or severity. patients with undisplaced anterior pelvic fractures, If a series contains a large number of stable, incon- noted that a technetium polyphosphate bone scan sequential fractures, the overall results with simple of the posterior sacroiliac complex gave a positive treatment will be excellent, whereas if it contains a reading in every case, indicating the definite pres- high percentage of displaced, unstable pelvic disrup- ence of a posterior lesion (Fig. 12.2). This was further 12.2 Understanding the Injury SCHA_12-Tile.indd 239 17.04.2005 14:27:56 Uhr 240 M. Tile a b c d Fig. 12.1a–e. Pelvic fracture personality types. The manage- ment of a pelvic disruption depends on a clear evaluation of the personality of the fracture. The good personality types as noted in the drawing in a and the radiograph in b which demonstrates a relatively undisplaced stable fracture of the pelvis is different than the bad personality type as noted in the drawing in c and the radiographs in d and e. The antero- posterior radiograph (d) is that of a 21-year-old man who sustained a crush injury to the pelvis. The degree of instabil- ity was not recognized, and the patient was treated with bed rest while the extremities were attended. The fi nal results (e) show severe shortening of the right hemipelvis with internal rotation. Note also the extremely high position of the right ischial tuberosity, which made sitting almost impossible (lower arrow). Marked shortening is indicated by the upper arrows above. Comparison of these two cases is like compar- ing apples to oranges or chalk to cheese e 12.2 Understanding the Injury SCHA_12-Tile.indd 240 17.04.2005 14:27:57 Uhr 12 Fractures of the Pelvis 241 a b Fig. 12.2. a Radiograph of a patient with an apparently undisplaced fracture of the inferior and superior pubic ramus on the right side (white arrow). No lesion is seen posteriorly. The deformity of the left hemipelvis represents a malunion of an old left acetabular fracture. b Technetium polyphosphate bone scan of the same patient clearly showing the increased uptake of the superior and inferior pubic ramus fracture anteriorly, but also a massively increased uptake at the right sacroiliac joint, indicating a posterior lesion (black arrow). (From Tile 1984; courtesy of Dr. S.D. Gertzbein) confirmed in a study by Bucholz (1981), in which Of greater importance than the site of the poste- posterior lesions at autopsy were found in all patients rior lesion is the degree of displacement of the pos- with pelvic trauma even when the radiograph had terior sacroiliac complex. This can best be seen on revealed only an anterior lesion. the inlet radiograph showing posterior displacement of the so-called sacrogluteal line (Fig. 12.4) and is best confirmed by computed tomography (CT) scan. 12.2.2 Therefore, the posterior lesion, although present, may Anatomical Lesions be undisplaced and have intact posterior ligaments, often associated with a sacral crush, or may be dis- The anterior pelvic lesion may be a symphysis pubis placed with a major ligamentous disruption of the disruption or overlap, or pubic rami fractures unilat- posterior pelvic complex (Fig. 12.5). erally or bilaterally. A symphysis disruption may also occur in combination with pubic rami fractures. The posterior lesion may be a fracture of the 12.2.3 ilium, often in the coronal plane, a dislocation or Stability of the Pelvis fracture-dislocation of the sacroiliac joint, or a frac- ture through the sacrum (Fig. 12.3). The commonest The anatomical lesions are important for surgical lesion is a sacral fracture followed by a combined management, but the stability factor is more impor- injury, i.e., a fracture-dislocation of the sacroiliac tant for overall decision making in the management joint, usually with a portion of the ilium remaining of patients. attached to the main sacral fragment. Stability may be defined as the ability of the Sacral fractures, in turn, may be classified as lat- pelvis to withstand physiological forces without eral, medial, or through the foramina or as complex significant displacement. It is obvious that pelvic types (H types). stability is dependent not only on the bony struc- 12.2 Understanding the Injury SCHA_12-Tile.indd 241 17.04.2005 14:27:58 Uhr 242 M. Tile a Fig. 12.4. The dotted line on the right represents the sacro- gluteal line on the inlet view of the pelvis. Any break in the continuity of this line, as shown on the left, represents dis- placement of the posterior complex, an ominous prognostic indicator. (From Tile 1984) b c Fig. 12.3a–c. Injuries to the posterior pelvic complex. The posterior injury may be a fracture through the ilium (a), a a pure dislocation of the sacroiliac joint (b, straight arrow), or a fracture through the sacrum (c, straight arrow). A common pattern is a fracture dislocation through the sacroiliac joint, as shown by the small curved arrows in b and c Fig. 12.5a,b. The posterior lesion may be stable or unstable. a The impacted right sacrum is clearly seen (white arrow). There is at least 1 cm of overlap between the two fragments. This posterior lesion is stable and cannot be moved. b The left sacral lesion is grossly unstable (black arrows). As well as the displacement at the fracture, all soft tissues are disrupted. (From Tile 1984) b 12.2 Understanding the Injury SCHA_12-Tile.indd 242 17.04.2005 14:27:58 Uhr 12 Fractures of the Pelvis 243 tures, but also on the strong ligamentous structures 12.2.3.1 binding together the three bones of the pelvis, i.e., Sacroiliac Complex the two innominate bones and the sacrum. If these ligamentous structures are removed, the pelvis The intricate posterior sacroiliac complex is a mas- falls into its three component parts. Moreover, sta- terly biomechanical structure able to withstand the bility is a spectrum: at one end of the spectrum is transference of the weight-bearing forces from the the intact pelvic ring, at the other end a completely spine to the lower extremities. The ligaments have unstable pelvis, an internal hemipelvectomy. In our a major role as posterior stabilizers, because the pelvic classification based on stability, the frac- sacrum, contrary to what is expected, does not form tures at the stable end are type A, at the unstable the shape of a keystone in a Roman arch, but is quite end type C, and those with partial stability in the the reverse.