Intraarticular entrapment of the obturator nerve in acetabular fracture

Management of Obturator Vessel Hemorrhage by Pubic Ramus Osteotomy During Acetabular Fixation-A Technical Trick

SUMMARY

It is known that hemorrhage from pelvic ring and acetabular fractures can cause hemodynamic instability. Methods to improve visualization and thus management of bleeding vessels are not commonly described. This report highlights techniques to manage hemorrhage from a retracted obturator vein during the definitive fixation of a complex acetabular fracture. After uncomplicated modified Stoppa anterior intrapelvic approach, abrupt and profuse bleeding was encountered from the distal end of a lacerated obturator vein, which had retracted into the obturator foramen. With unsuccessful attempts to achieve hemostasis, a superior pubic osteotomy was performed which allowed excellent visualization of the bleeding vein and ligation. It must be emphasized that the surgeon attempted all these other measures before performing an osteotomy. This technical trick contributes to the overall knowledge as a means of achieving emergent hemostasis associated with distal obturator vessel hemorrhage, a well described risk in complex acetabular fractures.

Injury of the obturator nerve in the modified Stoppa approach for acetabular fractures

INTRODUCTION

The modified Stoppa approach for acetabular fractures has become popular. However, the possibility of injury to the obturator nerve with this approach has not been sufficiently considered. We have experienced a case of nerve entrapment in severely displaced fractures. Therefore, we performed a retrospective study to: (1) evaluate the incidence of obturator nerve injury in the modified Stoppa approach for acetabular fractures; (2) analyze the relationship between the extent of displacement of the quadrilateral plate and injury to the obturator nerve.

HYPOTHESIS

We hypothesized that obturator nerve injury would be related to a marked medial displacement of the quadrilateral plate.

PATIENTS AND METHODS

We conducted a retrospective cohort study of 22 patients with acetabular fractures that were surgically treated with the modified Stoppa approach. The medial displacement of the quadrilateral plate was measured on a three-dimensional reconstruction image with the inlet view. Postoperative electrodiagnostic tests were performed based on clinical suspicion of neurological injury. Nerve injuries were divided into initial trauma or postoperative complication, and recovery of nerve function was evaluated. We identified the incidence of obturator nerve injury and analyzed the relationship between obturator nerve injury and medial displacement of the quadrilateral plate.

RESULTS

The incidence of obturator nerve injury was 2/22 (9.1%), and all injuries resulted from the initial trauma. The average displacement of the quadrilateral plate was 15.9±13.4mm. Patients were divided into two groups, using a displacement of 24mm as a cutoff point, identified using a receiver operating characteristic curve analysis. There were 16 patients in group 1 (<24mm) and 6 patients in group 2 (≥24mm). The incidence of obturator nerve injury from trauma was 0/16 (0%) in group 1 and 2/6 (33.3%) in group 2 (P=0.018).

CONCLUSIONS

No cases of postoperative obturator nerve injury were identified. Preoperative obturator nerve injury was more common in patients with a displacement of the quadrilateral plate≥24mm.

LEVEL OF EVIDENCE

IV, retrospective study.

What is the frequency of nerve injuries associated with acetabular fractures?

BACKGROUND

Acetabular fractures and surgical interventions used to treat them can result in nerve injuries. To date, only small case studies have tried to explore the frequency of nerve injuries and their association with patient and treatment characteristics. High-quality data on the risk of traumatic and iatrogenic nerve lesions and their epidemiology in relation to different fracture types and surgical approaches are lacking.

QUESTIONS/PURPOSES

The purpose of this study was to determine (1) the proportion of patients who develop nerve injuries after acetabular fracture; (2) which fracture type(s) are associated with increased nerve injury risk; and (3) which surgical approach was associated with the highest proportion of patients developing nerve injuries using data from the German Pelvic Trauma Registry. Two secondary aims were (4) to assess hospital volume-nerve-injury relationship; and (5) internal data validity.

METHODS

Between March 2001 and June 2012, 2236 patients with acetabular fractures were entered into a prospectively maintained registry from 29 hospitals; of those, 2073 (92.7%) had complete records on the endpoints of interest in this retrospective study and were analyzed. The neurological status in these patients was captured at their admission and at the discharge. A total of 1395 of 2073 (67%) patients underwent surgery, and the proportions of intervention-related and other hospital-acquired nerve injuries were obtained. Overall proportions of patients developing nerve injuries, risk based on fracture type, and risk of surgical approach type were analyzed.

RESULTS

The proportion of patients being diagnosed with nerve injuries at hospital admission was 4% (76 of 2073) and at discharge 7% (134 or 2073). Patients with fractures of the "posterior wall" (relative risk [RR], 2.0; 95% confidence interval [CI], 1.4-2.8; p=0.001), "posterior column and posterior wall" (RR, 2.9; CI, 1.6-5.0; p=0.002), and "transverse+posterior wall" fracture (RR, 2.1; CI, 1.3-3.5; p=0.010) were more likely to have nerve injuries at hospital discharge. The proportion of patients with intervention-related nerve injuries and that of patients with other hospital-acquired nerve injuries was 2% (24 of 1395 and 46 of 2073, respectively). They both were associated with the Kocher-Langenbeck approach (RR, 3.0; CI, 1.4-6.2; p=0.006; and RR, 2.4; CI, 1.4-4.3; p=0.004, respectively).

CONCLUSIONS

Acetabular fractures with the involvement of posterior wall were most commonly accompanied with nerve injuries. The data suggest also that Kocher-Langenbeck approach to the pelvic ring is associated with a higher risk of perioperative nerve injuries. Trauma surgeons should be aware of common nerve injuries, particularly in posterior wall fractures. The results of the study should help provide patients with more exact information on the risk of perioperative nerve injuries in acetabular fractures.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

SURGICAL MANAGEMENT OF OBTURATOR NERVE LESIONS

OBJECTIVE

Obturator neuropathy is a rare condition that may result from orthopedic, gynecological, or urological procedures or injuries. These pathologies are amenable to surgical intervention, and an accurate physical examination and electromyography are necessary before treatment.

METHODS

Six patients with obturator nerve lesions underwent surgical exploration and decompression or primary repair. Their charts were retrospectively reviewed, and the electromyographic, surgical, and follow-up data were recorded.

RESULTS

Postoperatively, all patients reported improved symptoms in the form of pain relief, numbness resolution, or improved adductor muscle strength.

CONCLUSION

Obturator nerve injury is a treatable condition with minimal surgical complications and morbidities.

Sciatic nerve entrapment in associated both-column acetabular fractures: a report of 2 cases and review of the literature

Sciatic nerve injury associated with acetabular fractures has been reported in most series. Typically, sciatic neuropraxia occurs from traumatic impaction or compression due to posterior hip fracture-dislocation. We report 2 patients with sciatic nerve entrapment within the posterior column components of their associated both-column acetabular fractures. Following neuroplasty through a Kocher-Langenbeck surgical approach, both patients' neurologic function improved. This unlikely cause of neurologic compromise should be considered in all patients with symptoms of sciatic nerve injury or irritation and particularly in the presence of a mechanical block during posterior column reduction through an ilioinguinal approach.