Multimodal nerve monitoring during periacetabular osteotomy identifies surgical steps associated with risk of injury

Bernese periacetabular osteotomy (PAO): from its local inception to its worldwide adoption

The development of the Bernese periacetabular osteotomy (PAO) is based on a structured approach starting with an analysis of the preexisting procedures to improve the coverage of the femoral head and was followed by a list of additional goals and improvements. Cadaveric dissections with a detailed description of the vascular supply of acetabulum and periacetabular bone set the stage for an intrapelvic approach, which offered the largest acetabular correction possible combined with safe intracapsular access. The final composition of osteotomies required the development of several instruments and cutting devices before the feasibility could be tested on a series of cadaveric hips.While the sequence of the osteotomies remained largely unchanged over time (except for the pubic and ischial osteotomies), several propositions for an easier/less invasive approach have been discussed; some made it into standard practice. Efforts were undertaken to optimize the learning curve and minimize failures using video-clips, hands-on courses, fellowships, publications, and ongoing mentoring programs. In retrospect, with almost 40 years of experience, such efforts have promoted a worldwide adoption of the Bernese periacetabular osteotomy.

[Complication management after periacetabular osteotomy]

BACKGROUND

Hip dysplasia is the most common cause of secondary hip osteoarthritis. The Ganz periacetabular osteotomy (PAO) is a well-established procedure that allows a reliable and reproducible correction of the complex pathology. The promising medium and long-term good treatment results are offset by the potential risk of complications from an invasive pelvic procedure. Considering the mainly young age of the patients, knowledge of the possible complications and the resulting adequate therapy is crucial.

TREATMENT DEVELOPMENT

The continuous development of surgical techniques and increase in overall surgical experience alongside the appreciation of critical surgical steps have led to a substantial reduction of serious complications. In addition, to improve patient outcome, a greater understanding of the associated pathologies that may be related to hip dysplasia is essential.

Neuromonitoring for Proximal Fibular Osteochondroma Excision

BACKGROUND

The peroneal nerve is at risk when excising tumors in the proximal fibula. The rate of nerve injuries during proximal fibular tumor resection varies from 3% to 20%. Our goal was to report our experience with resection of osteochondromas in the proximal fibula and describe the technique and utility of neuromonitoring during excision of proximal fibular osteochondromas (PFO).

METHODS

Patients with a diagnosis of symptomatic PFO who had undergone excision at one institution from 1994 to 2018 were included. An institutional review board-approved retrospective review was performed. Intraoperative neuromonitoring was provided from 2006 on by a single group utilizing a multimodality protocol.

RESULTS

This study contains 29 patients who had excision of osteochondromas in the proximal fibula. Of these 29 consecutively monitored patients, there were 34 involved extremities. Intraoperative neuromonitoring alerts occurred in 10/29 (34.5%) procedures, which included 3 electromyography (EMG) (30%), 2 motor-evoked potential (20%), 1 somatosensory-evoked potential (10%), and 4 alerts with a combination of EMG/motor-evoked potential/somatosensory-evoked potential changes (40%). The interventions that were taken resulted in resolution of the neuromonitoring changes in all procedures. Postoperatively, we noted 2 (6.9%) new mild sensory deficits, which resolved during follow up. There were 3 patients in whom pre-existing sensory-motor deficits improved but not completely after surgery, 1 motor weakness, and 2 with residual paresthesia. In those initially presenting with paresis, there was improvement in 8 of the 8 extremities by the last follow-up visit. Pain as a symptom was resolved in all cases. There were no iatrogenic foot drop injuries. The average follow up was 32.2 months.

CONCLUSIONS

Neuromonitoring during PFO excision demonstrated a high number of alerts, all of which resolved following timely corrective action. The use of neuromonitoring may help decrease the risk of iatrogenic postoperative neurological deficits following fibular osteochondroma surgery.

LEVEL OF EVIDENCE

Level IV.

Intraoperative neuromonitoring during distal femoral extension osteotomy in children with cerebral palsy

The most common treatment method for a fixed knee flexion contracture more than 10 degrees in cerebral palsy (CP) is distal femoral extension osteotomy (DFEO). However, a serious complication after a DFEO is neurological impairment. Its rates were reported as 5- 40%. Intraoperative neuromonitoring (IONM), widely used in spinal surgery and in other fields, is a valuable tool to define any neurological injury during operation. The aim of our study was to determine surgical steps with risk of neurological injury and to report if precautions would be effective in recovering signal loss. We performed IONM during DFEO of 23 knees of 12 children with CP. IONM was performed by recording somatosensory evoked potentials, transcranial motor evoked potentials and free-run electromyography during defined steps throughout the surgery. Preoperative and postoperative popliteal angles, flexion contractures and physeal posterior distal femoral angles were evaluated. We detected alert signals at osteotomy or manipulation steps of surgeries of all patients. We observed persistent alert signals in two cases (2 out of 23 knees; Group 2). In this group, the action potentials recovered only after 5 and 10 degrees of undercorrection at the osteotomy sites. Alert signals disappeared after a brief period of waiting in other cases. Throughout mean 37 months of follow-up, none of our patients experienced any neurological complication. The study concludes that the surgical steps in DFEO with a higher risk for a neurological complication were the osteotomy and manipulation steps. Alert signals were detected with the help of IONM, and preventive measures were effective in recovering neuromonitoring recordings.

Is intraoperative neuromonitoring effective in hip and pelvis orthopedic and trauma surgery? A systematic review

INTRODUCTION

Sciatic nerve injury is an uncommon but potentially devastating complication in hip and pelvis surgery. Intraoperative nerve monitoring (IONM) was applied since the seventies in neurosurgery and spine surgery. Nowadays, IONM has gained popularity in other surgical specialities including orthopaedic and trauma surgery. Aim of this systematic review is to resume the literature evidences about the effectiveness of intraoperative monitoring of sciatic nerve during pelvic and hip surgery.

METHODS

Two reviewers (GC and MD) independently identified studies by a systematic search of PubMed and Google Scholar from inception of database to 10 January 2021. Inclusion criteria were: (a) English written papers, (b) use of any type of intraoperative nerve monitoring during traumatic or elective pelvic and hip surgery, (c) comparison of the outcomes between patients who underwent nerve monitoring and patient who underwent standard procedures, (d) all study types including case reports. The present review was conducted in accordance with the 2009 PRISMA statement.

RESULTS

The literature search produced 224 papers from PubMed and 594 from Google Scholar, with a total amount of 818 papers. The two reviewer excluded 683 papers by title or duplicates. Of the 135 remaining, 72 were excluded after reading the abstract, and 31 by reading the full text. Thus, 32 papers were finally included in the review.

CONCLUSIONS

The use of IONM during hip and pelvis surgery is debated. The review results are insufficient to support the routine use of IONM in hip and pelvis surgery. The different IONM techniques have peculiar advantages and disadvantages and differences in sensitivity and specificity without clear evidence of superiority for any. Results from different studies and different interventions are often in contrast. However, there is general agreement in recognizing a role for IONM to define the critical maneuvers, positions or pathologies that could lead to sciatic nerve intraoperative damage.

LEVEL OF EVIDENCE

Level 2.

Postsurgical Neuropathy: A Descriptive Review

Postsurgical neuropathies represent an infrequent but potentially devastating complication of surgery that may result in significant morbidity with medicolegal implications. Elucidation of this phenomenon has evolved over the past few decades, with emerging evidence for not only iatrogenic factors contributing to this process but also inflammatory causes. This distinction can be important; for instance, cases in which inflammatory etiologies are suspected may benefit from further investigations including nerve biopsy and may benefit from treatment in the form of immunotherapy. In contrast, postsurgical neuropathies due to perioperative causes including anesthesia, traction, compression, and transection will not benefit in the same manner. This article summarizes early and current literature surrounding the frequency of new neurologic deficits after various surgical types, potential causes including anatomical and inflammatory considerations, and roles for treatment. To capture the scope of the issue, a literature review was conducted for human studies in English via MEDLINE and EMBASE from January 1, 1988 to March 31, 2018. Search terms included anesthesia and/or surgical procedures, operative, peripheral nervous system diseases, trauma, mononeuropathy, polyneuropathy, peripheral nervous system, nerve compression, neuropathy, plexopathy, postoperative, postsurgical, perioperative, complication. We excluded case series with less than 10 patients and review papers. We then narrowed the studies to those presented highlighting key concepts in postsurgical neuropathy.

Intraoperative monitoring of the femoral and sciatic nerves in total hip arthroplasty with high-riding developmental dysplasia

AIMS

This study aimed to explore whether intraoperative nerve monitoring can identify risk factors and reduce the incidence of nerve injury in patients with high-riding developmental dysplasia.

PATIENTS AND METHODS

We conducted a historical controlled study of patients with unilateral Crowe IV developmental dysplasia of the hip (DDH). Between October 2016 and October 2017, intraoperative nerve monitoring of the femoral and sciatic nerves was applied in total hip arthroplasty (THA). A neuromonitoring technician was employed to monitor nerve function and inform the surgeon of ongoing changes in a timely manner. Patients who did not have intraoperative nerve monitoring between September 2015 and October 2016 were selected as the control group. All the surgeries were performed by one surgeon. Demographics and clinical data were analyzed. A total of 35 patients in the monitoring group (ten male, 25 female; mean age 37.1 years (20 to 46)) and 56 patients in the control group (13 male, 43 female; mean age 37.9 years (23 to 52)) were enrolled. The mean follow-up of all patients was 13.1 months (10 to 15).

RESULTS

The two groups had no significant differences in preoperative data. In the monitoring group, ten nerve alerts occurred intraoperatively, and no neural complications were detected postoperatively. In the control group, six patients had neural complications. The rate of nerve injury was lower in the monitoring group than in the control group, but this did not achieve statistical significance. The degree of leg lengthening was significantly greater in the monitoring group than in the control group. In further analyses, patients who had previous hip surgery were more likely to have intraoperative nerve alerts and postoperative nerve injury.

CONCLUSION

Nerve injury usually occurred during the processes of exposure and reduction. The use of intraoperative nerve monitoring showed a trend towards reduced nerve injury in THA for Crowe IV DDH patients. Hence, we recommend its routine use in patients undergoing leg lengthening, especially in those with previous hip surgery. Cite this article: Bone Joint J 2019;101-B:1438-1446.

Intraoperative neurophysiology monitoring in scoliosis surgery in children

Objective

Intraoperative neurophysiology monitoring (INM) is thought to reduce the risk of postoperative neurological deficits in children undergoing scoliosis and spine deformity surgery. INM is being used increasingly despite conflicting opinions, varied results, non-standard alarm criteria and concern regarding cost effectiveness. In this paper we present our experience with INM in scoliosis and spine deformation surgery in children, propose alert criteria and preferred anaesthetics in clinical practice.

Methods

We retrospectively analysed our experience with INM in 56 children who had 61 scoliosis and spine deformity surgeries.

Results

INM was successfully undertaken with transcranial electrical motor evoked potentials (TcMEP) and somatosensory evoked potentials. There were no injuries due to INM. Four children had 5 alerts during 4 surgeries. A postoperative deficit was seen in one child only. No new postoperative deficits were seen in any child who did not have an alert during INM. Total intravenous anaesthesia was better for INM compared to inhalational anaesthetics.

Conclusions

INM is useful in scoliosis surgery; it is likely to mitigate the risk of new deficits following surgery. We recommend alert criteria for TcMEPs that include multiple facets - amplitude, stimulus paradigm, morphology. We recommend propofol and remifentanil, in preference to sevoflurane and remifentanil for anaesthesia during INM.

Significance

Our study adds to the literature supporting the role of INM in scoliosis surgery in children. We provide guidelines for alarm criteria in clinical practice and recommend the use of total intravenous anaesthesia as the preferred anaesthetic option.