[Is implant removal after percutaneous iliosacral screw fixation of unstable posterior pelvic ring disruptions indicated?]

Outcome of pelvic ring injuries

Outcome evaluation is of major importance to provide data to analyze the value of the chosen treatment concept. Despite an increasing effort of analyzing outcome after treatment of different pelvic ring injuries, a mixture of different outcome parameters is in use. The Majeed score is most frequently used for mid- to long-term evaluation and the quality of life is analyzed using the SF-36 score. The lack in nearly all studies is that different treatment concepts are used, and only selected evaluation parameters are reported. Until today, no well-accepted standardized measurement instruments are available to analyze the clinical and radiological results after pelvic ring injuries. Overall, stability-based long-term sequelae can be expected with increasing complaints from stable type A injuries to completely unstable type C injuries. Beside a fracture-type specific treatment, concomitant injuries of other injury regions and associated local pelvic injuries (complex pelvic trauma) seem to additionally influence the results. Results of treatment of specific fracture types are sparse as a wide range of different injury types and different treatment concepts are analyzed within these analyses. A sufficient pelvic outcome instrument which addresses relevant pelvic outcome parameters is still missing. Thus, future evaluation of long-term results after pelvic ring. injuries should include prospective, multicenter outcome studies with comparable parameters.

Higher pelvic incidence values are a risk factor for trans-iliac trans-sacral screw malposition in sacroiliac complex fracture treatment

BACKGROUND

Percutaneous iliosacral (IS) screw fixation and trans-iliac trans-sacral (TITS) screw fixation are clinically effective treatments of posterior pelvic sacroiliac fractures. In order to accurately assess the sacrum position relative to the pelvis, pelvic incidence (PI) is a commonly utilized radiographic parameter in sagittal view. This study aimed to investigate and compare the surgical outcomes and radiographic parameters of IS or TITS screw fixations for the treatment of posterior sacroiliac complex fractures with different PI values.

MATERIALS AND METHODS

The data on patients with posterior pelvic sacroiliac fractures who underwent percutaneous IS or TITS screw fixations, or both, at a single level I trauma center between January 2017 and June 2020 were reviewed. We documented the patient characteristics and fracture types, reviewed surgical records, and measured the radiographic parameters via plain films and multi-planar computed tomography (mpCT) images. Radiographic variations in PI, sacral slope, pelvic tilt, sacral dysmorphism, pelvic ring reduction quality, screw deviation angles, screw malposition grading, and iatrogenic complications were documented and analyzed.

RESULTS

A total of 85 patients were included, and 65 IS and 70 TITS screws were accounted for. Patients were divided into two groups according to screw fixation method and further divided into four sub-groups based on baseline PI values. The PI cutoff values were 49.85° and 48.05° in the IS and TITS screw groups, respectively, according to receiver operating characteristic analysis and Youden's J statistic. Smaller PI values were significantly correlated with sacral dysmorphism (p = 0.027 and 0.003 in the IS and TITS screw groups, respectively). Patients with larger PI values were at a significantly increased risk of screw malposition in the TITS screw group (p = 0.049), with no association in the IS screw group. Logistic regression confirmed that a larger PI value was a significant risk factor for screw malposition in the TITS screw group (p = 0.010). The post-operative outcomes improved from poor/fair (at 6 months) to good/average (at 12 months) based on the Postel Merle d'Aubigné and Majeed scores, with no significant differences between subgroups.

CONCLUSIONS

Both percutaneous IS and TITS screw fixations are safe and effective treatments for posterior pelvic sacroiliac fractures. Due to the higher risk of screw malposition in patients with larger PI values, it is crucial to identify potential patients at risk when performing TITS screw fixation surgery.

LEVEL OF EVIDENCE

Level III.

Do Transsacral-transiliac Screws Across Uninjured Sacroiliac Joints Affect Pain and Functional Outcomes in Trauma Patients?

BACKGROUND

Patients with pelvic ring displacement and instability can benefit from surgical reduction and instrumentation to stabilize the pelvis and improve functional outcomes. Current treatments include iliosacral screw or transsacral-transiliac screw, which provides greater biomechanical stability. However, controversy exists regarding the effects of placement of a screw across an uninjured sacroiliac joint for pelvis stabilization after trauma.

QUESTIONS/PURPOSES

Does transsacral-transiliac screw fixation of an uninjured sacroiliac joint increase pain and worsen functional outcomes at minimum 1-year followup compared with patients undergoing standard iliosacral screw fixation across the injured sacroiliac joint in patients who have sustained pelvic trauma?

METHODS

All patients between ages 18 and 84 years who sustained injuries to the pelvic ring (AO/OTA 61 A, B, C) who were surgically treated between 2011 and 2013 at an academic Level I trauma center were identified for selection. We included patients with unilateral sacroiliac disruption or sacral fractures treated with standard iliosacral screws across an injured hemipelvis and/or transsacral-transiliac screws placed in the posterior ring. Transsacral-transiliac screws were generally more likely to be used in patients with vertically unstable sacral injuries of the posterior ring as a result of previous reports of failures or in osteopenic patients. We excluded patients with bilateral posterior pelvic ring injuries, fixation with a device other than a screw, previous pelvic or acetabular fractures, associated acetabular fractures, and ankylosing spondylitis. Of the 110 patients who met study criteria, 53 (44%) were available for followup at least 12 months postinjury. Sixty patients were unable to be contacted by phone or mail and seven declined to participate in the study. Outcomes were obtained by members of the research team using the visual analog scale (VAS) pain score for both posterior sacroiliac joints, Short Musculoskeletal Functional Assessment (SMFA), and Majeed scores. Patients completed the forms by themselves when able to return to the clinic. A phone interview was performed for others after they received the outcome forms by mail or email.

RESULTS

There were no differences between iliosacral and transsacral-transiliac in terms of VAS injured (2.9 ± 2.9 versus 3.0 ± 2.8, mean difference = 0.1 [95% confidence interval, -1.6 to 1.7], p = 0.91), VAS uninjured (1.8 ± 2.4 versus 2.0 ± 2.6, mean difference = 0.2 [-1.3 to 1.6], p = 0.82), Majeed (80.3 ± 19.9, 79.3 ± 17.5, mean difference = 1.0 [-11.6 to 9.6], p = 0.92), SMFA Function (22.8 ± 22.2, 21.0 ± 17.6, mean difference = 1.8 [-13.2 to 9.6], p = 0.29, and SMFA Bother (24.3 ± 23.8, 29.7 ± 23.4, mean difference = 5.4 [-7.8 to 18.6], p = 0.42).

CONCLUSIONS

Placement of fixation across a contralateral, uninjured sacroiliac joint resulted in no differences in pain and function when compared with standard iliosacral screw placement across an injured hemipelvis at least 1 year after instrumentation. When needed for biomechanical stability, transsacral-transiliac fixation across an uninjured sacroiliac joint can be used without expectation of positive or negative effects on pain or functional outcomes at minimum 1-year followup.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Novel endoscopic sacroiliac screw removal technique: reduction of intraoperative radiation exposure

OBJECTIVE

We report in the following on our technique of endoscopic sacroiliacal screw removal as a new extra-articular endoscopic method in soft tissue surgery, aimed at the reduction of radiation exposure for both the patient and the surgical teams. Patients who underwent endoscopic implant removal from the dorsal pelvic ring (Group A) were retrospectively compared with a control group, in which the screws were removed via the conventional approach (Group B). The parameters of interest were the extent of x-ray exposure in seconds and surgical duration in minutes as well as approach related peri- and postoperative complications.

RESULTS

34 screws were removed endoscopically from 28 patients in group A and 35 screws from 29 patients in group B. The mean skin-to-skin time in group A was 36.1 (15-111) min and 32.7 (12-114) min in group B. The difference was not statistically significant (p > 0.05). The average radiation time in group A was 5.7 ± 3.2 s (range, 0-101 s), while in group B the radiation time was significantly longer (52.6 ± 23 s (range, 0-239 s); p = 0.005).

CONCLUSIONS

Endoscopic screw removal from the posterior pelvic ring reduces the intraoperative radiation time whereas the skin-to-skin times do not differ from the conventional procedure.

LEVEL OF EVIDENCE

Case-control study, Level III.

[Hardware removal after pelvic ring injury]

BACKGROUND

Pelvic ring fractures are considered as rare injuries. Minimally invasive sacroiliac screw fixation has been used increasingly in recent years as an operative strategy for the treatment of these injuries, if the dorsal pelvic ring needed to be addressed. Treatment options for the anterior pelvic ring comprise plates, screws or external fixation.

METHOD

Based on the limited number of publications on this subject and our own experience with 80 patients who suffered pelvic ring B- or C-type injuries during a period of 8 years we are able to show that the indication for hardware removal in the pelvic ring should be strictly defined.

RESULTS

In some cases like external fixation, implant-associated infection, malpositioning, allergic implant reaction, critical soft tissue covering, palpable hardware and consolidated juvenile fractures implant removal is certainly indicated. In patients without symptoms and in patients with trauma-associated symptoms which are not definitely associated with the hardware, the removal should be only indicated after thorough consideration of the risks versus the benefits and additionally by taking the initial injury pattern into account. If despite all these objections the hardware removal has been indicated it should always be considered that hardware removal may be challenging with several possible severe complications.

Minimally invasive stabilisation of posterior pelvic-ring instabilities with a transiliac locked compression plate

PURPOSE

Sacroiliac screw fixation is the method of choice for the definitive treatment of unstable posterior pelvic-ring injuries; however, this technique is demanding and associated with a high risk of iatrogenic neurovascular damage. This study evaluates whether minimally invasive transiliac locked compression plate stabilisation may be an alternative to sacroiliac screw fixation in unstable posterior pelvic-ring injuries.

METHODS

We performed a retrospective analysis of patients with unstable pelvic-ring injuries treated with a transiliac locked compression plate at a level I trauma centre. Outcome evaluation was assessed using the Pelvic Outcome Score and analysis of complications, intraoperative fluoroscopic time, and duration of the surgical procedure.

RESULTS

Twenty-one patients were available for follow-up after an average of 30 months. The main findings were as follows: Overall outcome for the Pelvic Outcome Score was excellent in 47.6% (ten patients), good in 19% (four patients), fair in 28.6% (six patients), and poor in 4.8% (one patient). Average operation time was 101 min and intraoperative fluoroscopic time averaged 74.2 s. No iatrogenic neurovascular injuries were observed.

CONCLUSION

Minimally invasive transiliac locked compression plate stabilisation may be a good alternative to sacral screw fixation because it is quick, safe and associated with a good functional outcome.