Motor nerve palsy following primary total hip arthroplasty

An anatomic consideration of the femoral nerve during direct anterior hip approach: A cadaveric study

PURPOSE

This study aimed to investigate the distance and correlation between the anatomy of the anterior side of the hip joint and the femoral nerve.

METHODS

Using ten fresh-frozen cadavers with twenty hip joints. We dissected and marked the femoral nerve in the inguinal area. Employing the direct anterior approach, we identified and marked study points, including the superior and inferior points of the anterior rim of the acetabulum, ¼ point, half point, and ¾ point along an imagined line connecting the formers, the inferomedial and mid aspect of the femoral neck, and the soft spot. Coronal plane measurements gauged the distance between these points and the femoral nerve. The collected data were analyzed to assess the distance and correlation.

RESULTS

In the coronal plane, the median distance between the inferior point of the anterior rim of the acetabulum and the femoral nerve was 0 millimeters (interquartile range [IQR] 0-0). Likewise, the median distance between the mid aspect of the medial side of the femoral neck and the femoral nerve was 0 millimeters (IQR 0-0). Additionally, the mean distance between the soft spot and the femoral nerve was 1.18 cm (SD 0.63).

CONCLUSION

Surgeons approaching the hip joint via the direct anterior approach should be cautious at the inferior point of the anterior rim of the acetabulum and the mid aspect of the femoral neck. The soft spot at the anterior rim of the acetabulum remains safe from direct injury when surgeons use the correct technique during anterior retractor insertion.

Functional Outcome of Uncemented Total Hip Replacement in Low Socioeconomic Group Using Modified Harris Hip Score: A Prospective Midterm Follow-Up Study

Background Total hip replacement is a safe and effective surgery with excellent outcomes in most patients with hip arthritis. The aim of this study was to evaluate functional outcomes and complications of total hip replacement among patients with low socioeconomic status in India. Methods We assessed 50 patients whose incomes fell below the poverty line and who underwent uncemented total hip replacement. We used a modified Harris Hip Score, replacing two items (one measuring range of motion and one measuring deformity) with two new ones (one related to return to professional activity and another regarding sexual activity). Results At the final follow-up, patients' modified Harris Hip Score improved from a preoperative mean value of 13.28 (0-46) to a postoperative mean value of 88.52 (64-100), suggesting marked improvement in functional outcome (p<0.001). In total, 32 (64%) patients returned to their original profession, and 12 (24%) switched to alternate work with mild pain. All patients reported satisfaction with their sexual activity at the final follow-up. Conclusions Many patients in India whose income is below the poverty line work in manual labor professions (e.g., farmers, masons, and cobblers) that increase their risk of hip damage. Total hip replacement is beneficial for these patients, offering good personal and professional quality of life after the surgery.

Femoral Nerve Palsy Post Total Hip Arthroplasty (THA) via a Posterolateral Approach

Femoral nerve palsy (FNP) is a debilitating and relatively rare complication of total hip replacement, which can worsen the functional prognosis. Various surgical approaches, including posterior, lateral, and anterior, are employed in total hip arthroplasty (THA), and the chosen approach can influence which nerve is affected. There is currently a lack of recent research on the prevalence of FNP and its typical course of recovery. In this clinical case, we report a rare incidence of FNP that presented as a complication of primary THA in a patient with end-stage osteoarthritis secondary to developmental dysplasia of the hip (DDH). A 35-year-old female presented with groin pain and restricted movement in her hip joint. She had a history of undergoing complex open-reduction surgery for hip dysplasia. During the physical examination, a positive Trendelenburg gait was identified, along with end-stage osteoarthritis (OA) secondary to the dysplasia. She subsequently underwent THA using a posterolateral approach. Following the procedure, she experienced neurological symptoms, leading to the diagnosis of FNP, a rare occurrence.

Compensation Claims After Hip Fracture Surgery in Norway 2008-2018

Background

Surgical complications contribute to the significant mortality following hip fractures in the elderly. The purpose of this study was to increase our knowledge of surgical complications by evaluating compensation claims following hip fracture surgery in Norway. Further, we investigated whether the size and location of performing institutions would influence surgical complications.

Methods

We collected data from the Norwegian System of Patient Injury Compensation (NPE) and the Norwegian Hip Fracture Register (NHFR) from 2008 to 2018. We classified institutions into 4 categories based on annual procedure volume and geographical location.

Results

90,601 hip fractures were registered in NHFR. NPE received 616 (.7%) claims. Of these, 221 (36%) were accepted, which accounts for .2% of all hip fractures. Men had nearly a doubled risk of ending with a compensation claim compared to women (OR: 1.8, CI, 1.4-2.4, P < .001). Hospital-acquired infection was the most frequent reason for accepted claims (27%). However, claims were rejected if patients had underlying conditions predisposing to infection. Institutions treating fewer than 152 hip fractures (first quartile) annually, had a statistically significant increased risk (OR: 1.9, CI, 1.3-2.8, P = .005) for accepted claims compared to higher volume facilities.

Discussion

The fewer registered claims in our study could be due to the relatively high early mortality and frailty in this patient group, which may decrease the likelihood of filing a complaint. Men could have undetected underlying predisposing conditions that lead to increased risk of complications. Hospital-acquired infection may be the most significant complication following hip fracture surgery in Norway. Lastly, the number of procedures performed annually in an institution influences compensation claims.

Conclusions

Our findings indicate that hospital acquired infections need greater focus following hip fracture surgery, especially in men. Lower volume hospitals may be a risk factor.

New Neuromuscular Training for Peripheral Nerve Disorders Using an Ankle Joint Hybrid Assistive Limb: A Case Series

Peripheral nerve disorder of the lower extremities causes drop foot and disturbs the daily living activities of patients. The ankle joint hybrid assistive limb (HAL) provides voluntary ankle joint training using surface bioelectrical signals from the muscles of the lower extremities. We investigated the neurological effects of ankle joint HAL training in three patients. Sensory nerve action potentials (SNAPs) and compound muscle action potentials (CMAPs) were analyzed for the peroneal and tibial nerves prior to the first ankle joint HAL training session. Integrated surface electromyography EMG signals were recorded before and after the HAL training sessions to evaluate the effects of training for neuromuscular disorders. The patients were hospitalized to receive rehabilitation with HAL training for 2 weeks. The HAL training was performed daily with two 60 min sessions. All cases demonstrated severe neuromuscular impairment according to the result of the CMAP. All integrated EMG measurements of antagonistic muscle activities decreased after the ankle joint HAL training. The manual muscle testing (MMT) scores of each muscle were slightly increased after the HAL intervention for Case 2(tibialis anterior, from 2 to 2+; gastrocnemius muscles, from 2- to 2; extensor digitorum longus, and extensor hallucis longus, from 1 to 3). The MMT scores were also slightly increased except for gastrocnemius muscle for Case 3 (tibialis anterior, extensor digitorum longus, and extensor hallucis longus, from 2- to 2). These two patients demonstrated voluntary muscle contractions and nerve signals in the CMAP before the HAL training. Even though the amplitude of CMAPs was low, the HAL training may provide voluntary ankle joint movements by reducing the antagonistic muscle contraction via computer processing. The HAL training may enhance muscle movement and coordination through motor learning feedback.

Intraoperative monitoring of the femoral nerve using free electromyography during total hip arthroplasty via the direct anterior approach

AIMS

This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different positions along the anterior acetabular wall may affect the femoral nerve during total hip arthroplasty (THA) when undertaken using the direct anterior approach (THA-DAA).

METHODS

Intraoperative free electromyography was performed during primary THA-DAA in 82 patients (94 hips). The highest position of the anterior acetabular wall was defined as the "12 o'clock" position (middle position) when the patient was in supine position. After exposure of the acetabulum, a retractor was sequentially placed at the ten, 11, 12, one, and two o'clock positions (right hip; from superior to inferior positions). Action potentials in the femoral nerve were monitored with each placement, and the incidence of positive reactions (defined as explosive, frequent, or continuous action potentials, indicating that the nerve was being compressed) were recorded as the primary outcome. Secondary outcomes included the incidence of positive reactions caused by removing the femoral head, and by placing a retractor during femoral exposure; and the incidence of femoral nerve palsy, as detected using manual testing of the strength of the quadriceps muscle.

RESULTS

Positive reactions were significantly less frequent when the retractor was placed at the ten (15/94; 16.0%), 11 (12/94; 12.8%), or 12 o'clock positions (19/94; 20.2%), than at the one (37/94; 39.4%) or two o'clock positions (39/94; 41.5%) (p < 0.050). Positive reactions also occurred when the femoral head was removed (28/94; 29.8%), and when a retractor was placed around the proximal femur (34/94; 36.2%) or medial femur (27/94; 28.7%) during femoral exposure. After surgery, no patient had reduced strength in the quadriceps muscle.

CONCLUSION

Placing the anterior acetabular retractor at the one or two o'clock positions (right hip; inferior positions) during THA-DAA can increase the rate of electromyographic signal changes in the femoral nerve. Thus, placing a retractor in these positions may increased the risk of the development of a femoral nerve palsy. Cite this article: Bone Joint J 2022;104-B(2):193-199.

Does robotic-assisted computer navigation improve acetabular cup positioning in total hip arthroplasty for Crowe III/IV hip dysplasia? A propensity score case-match analysis

AIMS

Total hip arthroplasty (THA) in patients with hip-dislocation dysplasia remains challenging. This study aims to evaluate whether these patients may benefit from robotic-assisted techniques.

METHODS

We reviewed 135 THAs (108 conventional THAs and 27 robotic-assisted THAs) for Crowe type III or IV from January 2017 to August 2019 in our institution. Robotic-assisted THAs were matched with conventional THAs at a 1:1 ratio (27 hips each group) using propensity score matching. The accuracy of cup positioning and clinical outcomes were compared between groups.

RESULTS

The inclination of the cup for conventional THAs and robotic THAs was 42.1 ± 5.7 and 41.3 ± 4.6 (p = 0.574), respectively. The anteversion of the cup for conventional THAs was significantly greater than that of robotic THAs (29.5 ± 8.1 and 18.0 ± 4.6; p < 0.001), respectively. The ratio of the acetabular cup in the Lewinnek safe zone was 37% (10/27) in conventional THAs and 96.3% (26/27) in robotic THAs (p < 0.001). Robotic THAs did not achieve better leg length discrepancy than that of conventional THAs (- 0.4 ± 10.9 mm vs. 0.4 ± 8.8 mm, p = 0.774). There was no difference in Harris Hip Score and WOMAC Osteoarthritis index between groups at the 2-year follow-up. No dislocation occurred in all cases at the final follow-up.

CONCLUSION

Robotic-assisted THA for patients with high dislocation improves the accuracy of the implantation of the acetabular component with respect to safe zone.

The direct anterior approach to the hip: a useful tool in experienced hands or just another approach?

The direct anterior approach (DAA) to the hip was initially described in the nineteenth century and has been used sporadically for total hip arthroplasty (THA). However, recent increased interest in tissue-sparing and small incision arthroplasty has given rise to a sharp increase in the utilization of the DAA. Although some previous studies claimed that this approach results in less muscle damage and pain as well as rapid recovery, a paucity in the literature exists to conclusively support these claims. While the DAA may be comparable to other THA approaches, no evidence to date shows improved long-term outcomes for patients compared to other surgical approaches for THA. However, the advent of new surgical instruments and tables designed specifically for use with the DAA has made the approach more feasible for surgeons. In addition, the capacity to utilize fluoroscopy intraoperatively for component positioning is a valuable asset to the approach and can be of particular benefit for surgeons during their learning curve. An understanding of its limitations and challenges is vital for the safe employment of this technique. This review summarizes the pearls and pitfalls of the DAA for THA in order to improve the understanding of this surgical technique for hip replacement surgeons.

Course of the sciatic nerve on magnetic resonance imaging in patients with osteoarthritis of the hip

BACKGROUND

Sciatic nerve palsy is a serious complication after total hip arthroplasty (THA). This is the first study to report the relationship between the sciatic nerve and the acetabulum on magnetic resonance imaging (MRI) before THA.

METHODS

235 patients underwent 261 elective, primary THAs via the mini-incision posterolateral approach. We measured the horizontal distance (mm) and vertical distance (mm) from the posterior edge of the acetabulum to the sciatic nerve by T1-weighted imaging on an axial section of the centre of the femoral head. We defined the Dysplastic Group as having a posterior acetabular sector angle (PASA) <90° and the Non-dysplastic Group as having a PASA ⩾ 90°. We compared anatomical distances and angles between the 2 groups.

RESULTS

The horizontal and vertical distances were (mean ± SD) 8.0 ± 9.2 mm and 14 ± 5.0 mm from the posterior edge of the acetabulum to the lateral edge of the sciatic nerve, respectively. The acetabular anteversion (AA), anterior acetabular sector angle (AASA), and PASA were (mean ± SD) 19 ± 6.7°, 49 ± 8.4°, and 87 ± 8.6°, respectively. The horizontal and vertical distances were positively correlated (p < 0.0001). AA and PASA were positively correlated with the horizontal distances (p < 0.0001) as well as with the vertical distances (p = 0.0017 and p = 0.0438, respectively). The horizontal and vertical distances were significantly shorter in the Dysplastic Group than in the Non-dysplastic Group (p < 0.0001 and p = 0.021, respectively).

CONCLUSIONS

In cases of posterior acetabular dysplasia we have to be mindful of the course of the sciatic nerve.

Does surgical body position influence the risk for neurovascular injury in total hip arthroplasty? A magnetic resonance imaging study

BACKGROUND

Neurovascular injury is a critical complication in total hip arthroplasty (THA). However, neurovascular geographic variations around the hip joint in different body positions have not been examined. This study investigated the differences in hip neurovascular geography in the supine and lateral positions using magnetic resonance imaging (MRI).

HYPOTHESIS

The neurovascular geography of the hip is influenced by differences in surgical body position.

PATIENTS AND METHODS

This was a single-center prospective study of 15 healthy volunteers enrolled between January 2018 and March 2019. Each subject's bilateral hips were scanned with a 3-T MRI scanner in both the supine and lateral positions. In T1-weighted axial images at the level of the hip center, the anterior and posterior acetabular edges were defined as reference points at which retractors are commonly placed during surgery. We measured the distance between the anterior acetabular edge and the femoral nerve (dFN), femoral artery (dFA), and femoral vein (dFV), as well as that between the posterior acetabular edge and the sciatic nerve (dSN). The primary outcome measures were the distances in both the supine and lateral positions.

RESULTS

dFN, dFA, and dFV in the supine and lateral positions (mm, mean±standard deviation) were 25.8±5.6 and 32.4±6.4 (p<0.0001), 25.7±4.5 and 32.2±5.0 (p<0.0001), and 26.5±4.8 and 32.3±5.1 (p<0.0001), respectively. Most of these elements moved anteromedially in the lateral position compared to the supine position. There was no significant difference in dSN between the supine and lateral positions (23.7±4.9 and 24.5±6.5 (p=0.46).

DISCUSSION

THA in the supine position may be accompanied by a higher risk of femoral neurovascular injury than that in the lateral position. The application of our findings could reduce the risk of femoral neurovascular injury during THA.

LEVEL OF EVIDENCE

III; prospective diagnostic case control study.

Iatrogenic femoral nerve injuries: Analysis of medico-legal issues through a scoping review approach

Purpose

Accidental femoral nerve injury is a well-known iatrogenic complication of orthopaedic, abdominal, and pelvic surgery. Because of the largely transitory nature of the symptoms associated with nerve damage, its true incidence is in all likelihood underestimated. This work aims to illustrate the surgical contexts within which this nerve injury is reported, based on the evidence obtained from a Scoping Review of the literature of the last 20 years, with specific reference to the underlying etiopathogenetic mechanisms and prognostic outcomes, to highlight the evaluation issues of medico-legal interest related to this pathology.

Methods

We conducted a Scoping Review of iatrogenic femoral nerve injuries reported between 2000 and 2021 by searching the electronic databases Pubmed, Scopus, Ovid Medline, Ovid Emcare, and Web of Science.We conducted the review according to the five-step methodology outlined by Arksey and O'Malley.

Results

The literature search identified 104 papers, including case reports, case series, and retrospective studies. Surgical contexts within which iatrogenic femoral nerve injuries were reported include orthopaedic, abdominal, gynaecological, urological, vascular, and plastic surgery, as well as locoregional anaesthesiological procedures. The long-term prognosis was generally favourable.

Conclusions

Because of its frequent iatrogenic genesis, femoral nerve injury is a topic of intense medico-legal interest. From the perspective of estimating the patient's disability, the mostly favourable nature of the prognosis makes the medico-legal assessment, in some respects, complex, thus requiring a precise evaluation methodology.

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.

Incidence, Injury Mechanisms, and Recovery of Iatrogenic Nerve Injuries During Hip and Knee Arthroplasty

Iatrogenic nerve injury is a rare but potentially devastating complication in total joint arthroplasty of the hip and the knee. Multiple previous studies have evaluated the incidence, mechanisms of injury, recovery, and potential treatments for this complication. Injury in total hip arthroplasty generally involves direct injury of sensory nerves from the incision, direct or traction injury of during exposure, or limb lengthening. Injury in total knee arthroplasty generally involves direct injury of sensory nerves from incision, injury due to errant placement of retractors, during balancing, or from traction because of deformity correction. Treatment of iatrogenic nerve injuries has ranged from observation, intraoperative prevention by nerve monitoring, limb shortening postoperatively, medications, and decompression. The orthopaedic surgeon should be versed in these etiologies to advise their patients on the incidence of injury, to prevent occurrence by understanding risky intraoperative maneuvers, and to select appropriate interventions when nerve injuries occur.

Artroplastia total do quadril não cimentada em pacientes com osteoartrose secundária à doença de Legg-Calvé-Perthes em comparação com a osteoartrose primária: Um estudo caso-controle

Objective  To perform a comparative clinical, functional and radiographic evaluation of total hip arthroplasty (THA) performed with a cementless prosthesis in cases of osteoarthrosis secondary to Legg-Calvé-Perthes Disease (LCPD) and in cases of primary osteoarthrosis.

Methods  In the present case-control study, we reviewed medical records of patients admitted to a university hospital between 2008 and 2015 to undergo THA due to LCPD sequelae and compared them with a control group of patients who underwent the same surgery due to primary hip osteoarthrosis. We recruited patients for clinical, functional, and radiographic analysis and we compared the evaluations in the immediate postoperative period and at the last follow-up visit, considering surgical time, size of prosthetic components, and complications.

Results  We compared 22 patients in the study group (25 hips) with 22 patients (25 hips) in the control group, all of whom had undergone THA with the same cementless prosthesis. There was greater functional impairment in the group of patients with LCPD sequelae ( p  = 0.002). There were 4 intraoperative femoral periprosthetic fractures in the LCPD group and none in the primary osteoarthrosis group ( p  = 0.050).

Conclusions  There is an increased risk of intraoperative periprosthetic femoral fracture and worse clinical-functional results in patients undergoing cementless THA due to osteoarthrosis secondary to LCPD sequelae than in those who have undergone the same surgery due to primary hip osteoarthrosis.

Evaluation of Direct Anterior Approach for Revision Total Hip Arthroplasty: A Systematic Review

The direct anterior approach (DAA) is an established approach for total hip arthroplasty (THA) but has been sparingly tried for revisions. The purpose of this study was to examine the available literature in order to consolidate information available on revision THA using the DAA. A PubMed, Embase, and Scopus search was performed using relevant keywords. Studies reporting on patients undergoing revision THA using DAA were included for analysis. In a review of the literature, nine studies matched the pre-decided inclusion criteria with 319 hip joints undergoing revision THA. Mean follow-up of all included studies was 34 months. The indications of revision after primary THA in decreasing order were aseptic loosening (53%), prosthetic joint infection (20.7%), peri-prosthetic fracture (16.9%), dislocation (7.2%), psoas impingement (1.9%), polyethylene wear (1.2%), pain (0.6%), and instability (0.3%). Of the 319 revisions evaluated, 107 underwent a stem revision, 142 underwent cup revision, 49 underwent a combined revision, and 21 underwent isolated liner/head change. A statistically significant improvement in functional score (P<0.05) was observed for all studies reporting on functional outcomes. A low complication rate (51/319, 16.0%), which includes dislocation (12), infection (12), loosening of the acetabular shell (5), peri-prosthetic fractures (6), haematoma (4), and transient nerve palsy (6), was reported. Based on available level III-IV evidence, DAA appears to be a reliable alternative for revision of the failed hip arthroplasty with acceptable complication rates. Evidence of a higher quality is needed to further characterize its role in revision scenarios.

The intraoperative use of a calliper predicts leg length and offset after total hip arthroplasty. Component subsidence influences the leg length

Background

The purpose of total hip arthroplasty (THA) post-surgery and proper physiotherapy is positive recovery for the patient. Consideration is given to hip replacement biomechanics by ensuring no discrepancies in limb length (LL) and a stable prosthesis. Therefore, the patient must have proper preoperative planning and communication and a clear understanding of what to expect.

Methods

A prospective series of 59 THA operated by a single surgeon via Hardinge approach was studied, using an intraoperative calliper (CAL) to predict the change of LL and offset. We compared the results of the intraoperative changes before and after THA implantation with the reference of these values on anteroposterior x-ray pelvis. The importance of leg length balance and a good offset restoration is questioned, and the effect of component subsidence on leg length is considered.

Results

The average preoperative leg length discrepancy was −6.0 mm, postoperatively +3.6 mm. There was a strong correlation between the CAL measurements and the values on the x-ray (LL, r=0.873, p<0.01; offset, r=0.542, p<0.01). Reliability is better for limb length than for offset. These results are comparable within the literature and the statistical results from other studies reviewed. In addition, we evaluate the importance of subsidence of the prosthesis components for long-term results.

Conclusion

The intraoperative use of CAL gives excellent results in predicting the final LL and offset after THA. Considering subsidence of prosthesis components, a target zone around +5 mm might be more suitable for leg length directly postoperatively. Moreover, surgeons must discuss the topic of leg length discrepancy (LLD) intensively with the patient pre-operatively.

Level of evidence

Level 4, prospective cohort study

Iatrogenic lesions of the peripheral nervous system in orthopaedic surgery and traumatology procedures

OBJECTIVE

To describe iatrogenic lesions of the peripheral nervous system and their relationship with different orthopaedic and traumatological procedures, through their assessment by means of electromyographic study.

MATERIAL AND METHODS

Retrospective descriptive study of the electromyographies performed in the clinical neurophysiology service of the Hospital General Universitari de Castelló between July 2015 and March 2019, recovering those in which the aetiology was diagnosed as iatrogenic in relation to surgical procedures and analysing those that were initiated after orthopaedic and traumatological procedures.

RESULTS

Of the total number of electromyographies reviewed, 1.37% corresponded to iatrogenic surgical lesions and 55.1% of these were secondary to orthopaedic surgery and traumatology procedures, the incidence in relation to the procedures performed was 0.65%. The most frequent locations related to injuries were the lumbar spine, hip and hand/wrist. Injuries due to postural causes not directly related to the surgical field are noteworthy.

CONCLUSION

Iatrogenic injuries to the peripheral nervous system after orthopaedic surgery and traumatology procedures are infrequent, but given their mechanism of injury and the high severity of most of them, it would be advisable to implement corrective mechanisms to reduce their incidence.

LEVEL OF EVIDENCE

IV.

A comparison of short term complication rate between 44 two- and 385 one-stage septic exchange arthroplasties in chronic periprosthetic joint infections

BACKGROUND

Periprosthetic joint infection is a serious disease with severe consequences for the patient's life. It is not known whether one-stage or two-stage replacement arthroplasty is superior. So far, there have been no studies on short-term complications between both surgical procedures. Therefore, we performed a retrospective study aiming to determine: 1) Does two-stage septic exchange arthroplasty have a higher short-term complication rate than one-stage? 2) Is there a difference in length of hospital stay and the in-hospital mortality rate between two- and one-stage septic exchange arthroplasty?

HYPOTHESIS

Two-stage septic exchange arthroplasty has a higher short-term complication rate than one-stage.

PATIENTS AND METHODS

Retrospectively 429 patients who underwent a one- or two stage revision arthroplasty (288 hips and 141 knees) due to chronic PJI between January 2015 and December 2016 were recruited (one-stage: n=385, two-stage: n=44). Differences in postoperative complications, surgical therapy, ASA, Charlson Comorbidity Index (CCI), length of hospital, need for plastic surgery, pathogen, in-hospital morbidity and in-hospital mortality were compared using multiple logistic and Poisson regression. Regarding comorbidities, age, gender and BMI the groups were comparable.

RESULTS

It was 3.5 times more likely to suffer from a medical complication if a two stage septic exchange was performed (OR 3.465, (95% CI: 2.573-4.358) [p<0.01]). In medical complications the two-stage group showed significantly more events (two-stage: 9 of 44=20.5%; one-stage: 30 of 385=7.8% [p=0.013]). The one-stage group showed more (not significant) nerve palsies after hip septic exchange. There was no difference in mortality between the groups (two-stage: 1/44=2.3%; one-stage: 3/385=0.8% [p=0.882]), the overall mortality was 0.93%. The duration of hospital stay was 23.9±19 days for the one-stage and 42.2±17.7 days for the two-stage group (p<0.001).

CONCLUSION

We found that it is more likely to develop a medical complication after two-stage septic revision arthroplasty. There was no difference in overall surgical complications between the two surgical approaches. We did not find a significant difference in short term mortality between the two techniques, although the mortality rate was slightly higher in the two-stage group.

LEVEL OF EVIDENCE

III, retrospective case control study.

The distance between the femoral nerve and anterior acetabulum is significantly shorter in hip osteoarthritis than in non-osteoarthritis hip

Background

The appropriate position of retractors to minimize the risk of femoral nerve palsy remains uncertain. The purpose of this imaging study was to evaluate the distance between the femoral nerve (FN) and anterior acetabulum (AA) in hip osteoarthritis (OA).

Methods

Forty-one patients with unilateral hip OA underwent magnetic resonance imaging. Three measurement levels were defined and the minimum distance between the femoral nerve (FN) margin and anterior acetabulum (AA) rim was measured on axial T1-weighted images on the OA and normal sides at each level, with reference to an advanced neurography view. The cross-sectional area (CSA) of the iliopsoas muscle was also measured at each level bilaterally by three observers. Distances and CSAs were compared between the OA and normal side. Multiple regression analysis was performed to identify variables associated with the distance in OA.

Results

The mean minimum FN to AA distances in OA were 19.4 mm at the top of the anterior inferior iliac spine (AIIS), 24.3 mm at the bottom of the AIIS, and 21.0 mm at the tip of the greater trochanter. These distances were significantly shorter than in normal hips at the top and bottom of the AIIS, with mean differences of 1.6 and 5.8 mm, respectively (p = 0.012, p < 0.001). CSAs of the iliopsoas in OA were significantly smaller at all levels (all p < 0.001), with reductions of 10.5 to 17.9%. The CSA of the iliopsoas at the bottom of the AIIS was associated with the FN to AA distance at the same level (p = 0.026). Interobserver reliabilities for measurements were very good to perfect (intraclass correlation coefficients 0.897 to 0.966).

Conclusions

To minimize the risk of femoral nerve palsy, surgeons should consider the change of the femoral nerve to anterior acetabulum distance in osteoarthritic hip surgery.

Post-operative radiculitis following one or two level anterior lumbar surgery with or without posterior instrumentation

The purpose of this study was to define risk factors for non-compression radiculitis following anterior lumbar surgery with or without posterior instrumentation and to define a time to resolution. In this study, we followed 58 consecutive patients who had anterior lumbar surgery with or without posterior instrumentation. We identified those with and without post-operative radiculitis. There as a 36.5% rate of postoperative radiculitis. We found that there was a moderate to strong correlation with height change and radiculitis (p = 0.044). Additionally patients treated with rh-BMP2 had a higher risk of developing symptoms. In all of the patients who developed postoperative radiculitis, symptoms resolved by 3 months. In conclusion 36.5% of patients developed post operative radiculitis. This was associated with the use of rh-BMP2, as well as increasing disc height through surgery. All symptoms resolved by 3 months posoperatively.

Nerve palsy, dislocation and revision rate among the approaches for total hip arthroplasty: a Bayesian network meta-analysis

BACKGROUND

Total hip arthroplasty (THA) is one of the most performed intervention in orthopaedics surgery. Currently, there is no unanimous approval concerning the best approach for THA in terms of nerve palsies, dislocations and further revisions. Hence, a Bayesian network meta-analysis was conducted.

METHODS

The present study was conducted according to the PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of healthcare interventions. The literature search was performed in September 2019. The NMA was performed through the STATA Software/MP routine for Bayesian hierarchical random-effects model analysis.

RESULTS

Data from 10,675 THA were collected. The mean follow-up was 10 months. The anterior approach reported the lowest risk to incur a post-operative dislocation (overall inconsistency P = 0.99). The posterolateral approach reported the lowest risk to incur a nerve palsy (overall inconsistency P = 0.77). The funnel plot revealed a low risk of publication bias. The lateral approach was found to have the lowest risk of resulting in a revision surgery (overall inconsistency P = 0.90).

CONCLUSION

According to our network comparisons, the posterolateral approach for THA represent the favourable exposure with regards to nerve palsy, further dislocations and revision surgeries.

Do Acetabular Buttress Augment Pose Risk to the Superior Gluteal Nerve? A Cadaveric Study

Background

Management of acetabular defects in total joint reconstruction can be challenging. Various algorithmic approaches have been developed, with some recommending using posterosuperior acetabular buttress augments for severe defects. The superior gluteal nerve lies in close proximity to their application, and damage to it results in deterioration of hip stability and gait mechanics. There has been investigation into the relationship of the superior gluteal nerve to various anatomic points. To our knowledge, no study exists examining the relationship between the acetabular rim and the superior gluteal nerve for the application of these particular devices.

Methods

Ten adult cadaver specimens were examined. A reproducible technique in relation to the typical placement of a buttress augment was used. From a distance of 20 millimeters (mm) lateral to the greater sciatic notch, the distance from the superior gluteal nerve to the posterosuperior acetabular rim was measured.

Results

The average distance between the posterosuperior acetabular rim and the superior gluteal nerve was found to be 52 mm, ranging from 48 mm to 60 mm.

Conclusion

With proprietary acetabular augments measuring up to 68 mm in length, the superior gluteal nerve could be at substantial risk with placement of these devices. Surgeons should take great care with dissection for and intraoperative placement of these devices, and particularly strive for optimized prosthetic hip stability to mitigate the risk of dislocation from nerve injury. To our knowledge, this study is the first of its kind and provides valuable anatomic and operative knowledge during these highly complex cases.

Post-Surgical Inflammatory Neuropathy: An Underappreciated but Critical and Treatable Cause of Postoperative Neuropathy

The diagnosis and management of postoperative nerve injury can be a challenging and frustrating proposition for the patient, surgeon, and anesthesia provider. Unfortunately, in many cases, the true etiology is never elucidated and the injury is ascribed to positioning or a nerve block with “expectant management” being the order of the day, which can result in persistent disability for the patient. However, there is a rare subset of disorders affecting the nervous system that can masquerade as a peripheral nerve injury that warrants further investigation of risk factors and co-morbidities when other common causes of nerve injury are ruled out. We describe a patient with rheumatoid arthritis that underwent revision hip arthroplasty and presented almost immediately in the postoperative period with what was initially diagnosed as femoral nerve palsy. Further diagnostic workup later revealed that she had suffered from postoperative inflammatory neuropathy resulting in lumbosacral plexus injury and not a discrete nerve injury. Had the true cause been identified early enough, treatment with corticosteroids could have been initiated in an attempt to mitigate and perhaps reverse the progress of the neuropathy. We present this cautionary tale to remind practitioners to continue to be vigilant and consider more esoteric and unconventional diagnoses in the workup of perioperative neuropathies.  

A comparison of leg length discrepancy between direct anterior and anterolateral approaches in total hip arthroplasty

Background

Leg length discrepancy (LLD) after total hip arthroplasty (THA) is a known source of complications and a leading cause of litigation (J Bone Joint Surg Br 87:155–157, 2005). There are limited studies investigating surgical approach combined with the use of fluoroscopy intraoperatively and their potential effects on LLD after THA. The purpose of this study was to compare the direct anterior (DA) approach utilizing a fluoroscopic overlay technique and anterolateral (AL) approach and their potential effect on LLD.

Methods

We retrospectively reviewed 121 patients who had undergone primary THA from September 1, 2016 to November 1, 2018 by either DA or AL approach by two separate surgeons. Leg length discrepancies were measured on pre-operative post-anesthesia care unit (PACU) and on post-operative low anterior/posterior (AP) pelvis plain radiographs by two investigators blinded to each other’s measurements. To confirm inter-observer and intra-observer reliability between LLD measurements amongst investigators, a Pearson correlation test was performed. The primary outcome measurement was leg length discrepancy (LLD).

Results

We observed LLD > 1.0 cm and LLD > 1.5 cm in the DA and AL groups. The DA approach group showed a mean LLD of 4.5 mm against 7.76 mm in the AL group (p < 0.00001). There was a significantly higher rate of LLD in the AL group as compared to the DA group (LLD> 1 cm (28% vs. 8%, p = 0.0037) and LLD > 1.5 cm (7% vs. 0%, p = 0.0096). The LLD measurements showed strong correlation in terms of inter-observer (r = 0.95) and intra-observer reliability (r = 0.99) between the two investigators (p < 0.001).

Conclusion

In our patient cohort, the DA approach with fluoroscopic overlay technique had less LLD in comparison with the AL approach, suggesting that intraoperative fluoroscopic use does have an impact on LLD.

Split and partially entwined sciatic nerve following closed reduction of a dislocated hip prosthesis

We present a case of split and partially entwined sciatic nerve by a femoral prosthesis following closed reduction of a dislocated hip replacement. This complication is very rare and there are only few cases reported in the literature, with even less accompanied by supporting MRI. We present MRI features of a split and partially entwined sciatic nerve around a hip prosthesis.

Long-term results of cementless total hip arthroplasty for the treatment of ankylosed hip

PURPOSE

The purpose of this study was to report the long-term results of total hip arthroplasty (THA) for the treatment of ankylosed hip.

METHODS

Twenty-nine consecutive THAs were performed in 26 patients. The mean age of the patients at the time of the operation was 43.3 years (range, 19-69 years). We used cementless fixation in all hips and the mean duration of follow-up was 10.1 years (range, 4.5-20 years). Radiological evaluation of components, osteolysis, radiolucent lines and loosening were assessed. The Harris Hip Score (HHS), range of motion (ROM), limb-length discrepancy and walking capacity with or without any support were used preoperatively and at final follow-up for clinical evaluation. Survivorship analysis was conducted using the Kaplan-Meier method using second revision for any reason as the endpoint.

RESULTS

The mean HHS was 85.6 (range, 55-98) points and mean ROM was 110.5° for flexion. The mean limb-length discrepancy improved from 4.1 cm to 1.1 cm. Positive Trendelenburg sign was recorded in 31% of the patients and 24% of patients needed any support for walking postoperatively. We observed surgical complications related to abductor arm in 25% of the patients. Radiolucency on the acetabular side was seen on one or more zones in 15 patients (16 hips). One aseptic acetabular component loosening was observed. On the femoral side, 11 patients demonstrated non-progressive radiolucent lines and osteolysis around the stem was seen in four hips but there was no aseptic stem loosening. The Kaplan-Meier survival rate considering revision for any reason as the endpoint was 81.5%, for aseptic loosening 91.3%, for a worst-case scenario of 66.4% at 10 years.

CONCLUSION

Cementless fixation showed good to excellent results at 10 years. Preoperative and postoperative abductor status of the patient is critical for patient satisfaction.

Medial femoral cutaneous nerve conduction study with distal recording: A novel technique

BACKGROUND

A new technique to obtain the sensory nerve action potential (SNAP) of the medial femoral cutaneous nerve is described.

METHODS

SNAPs were recorded from 104 subjects with a bar recording electrode 10 cm proximal to the patella along an imaginary line drawn between the medial edge of the patella and the femoral pulse below the inguinal ligament. Stimulation was applied 14 cm proximal to the recording point.

RESULTS

There were 104 healthy subjects. Onset latency of the SNAPs was 2.20 ± 0.16 ms (mean ± SD), peak latency was 2.70 ± 0.16 ms, peak-to-peak amplitude was 7.5 ± 3.0 μV, and conduction velocity was 51.5 ± 3.0 m/s. The side-to-side difference in the mean amplitude was 22.27 ± 13.6%.

CONCLUSIONS

This new technique is easy, reliable, and reproducible, and should prove useful for the evaluation of neuropathies of the medial femoral cutaneous nerve.

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.

Mechanical Properties of the Human Tibial and Peroneal Nerves Following Stretch With Histological Correlations

Despite the extensive literature regarding peripheral nerve stretch injuries, there are few studies that compare the nerve histology with the mechanical properties in humans. There is clinical evidence suggesting that the peroneal nerve is at greater risk for injury compared to the tibial nerve following total hip arthroplasty and hip trauma. We examined the two nerves from fresh human cadavers with or without controlled stretch. The mechanical properties, stiffness, and strain were compared with light microscopic preparations in longitudinal sections stained by the trichrome method for collagen and showing the effects of structural deformation. The tibial nerve had an average failure load 1.7× that for the peroneal nerve (P = 0.0001). Although the corresponding average stiffness showed a trend toward being larger (4.39 vs. 3.81 N/mm), the difference was not significant (P = 0.126). Histologically, the perineurium along with the underlying nerve fascicle was undulated in the control specimens and straightened out in the stretched specimens. Peroneal nerves went on to failure at lower loads and exhibited a wavy pattern on pathologic slides after failure, which shows that peroneal nerves fail mechanically before they can unfold. The tibial nerve has a biomechanical and histological advantage compared to the peroneal nerve during tensile testing, which could be the reason why it is less commonly damaged. We conclude that the perineurium is especially protective against deformation changes in human nerves relative to the respective nerve size and number of fascicles. Anat Rec, 302:2030-2039, 2019. © 2019 American Association for Anatomy.

Risk Factors for Peripheral Nerve Injury After 207,000 Total Hip Arthroplasties Using a New York State Database (Statewide Planning and Research Cooperative System)

BACKGROUND

Peripheral nerve injury (PNI) is a devastating complication following total hip arthroplasty (THA). The purpose of this study was to identify risk factors for PNI after THA using a New York Statewide Planning and Research Cooperative System (SPARCS).

METHODS

The SPARCS database was queried to identify patients who had undergone THA from 1996 to 2011. Patient demographics, medical history, surgical details, hospital characteristics, and in-hospital complications were recorded. Cases in which a new unilateral PNI was identified were compiled, as were control cases in which a new PNI did not occur. The characteristics of cases and controls underwent univariate testing and a multivariate logistic regression using Akaike information criterion model selection to identify risk factors for the development of PNI after THA.

RESULTS

207,981 cases were identified, and 487 were coded as having a new PNI. Preexisting spinal conditions (odds ratio [OR] = 2.55, confidence interval [CI] = 1.61-3.83) were strongly correlated with the development of PNI postoperatively, as was dislocation (OR = 2.58, CI = 1.01-5.30) and diabetes with chronic complications (OR = 2.26, CI = 0.96-4.43). Younger age, in-hospital complications, and thromboembolic events were also associated with postoperative PNI.

CONCLUSION

The incidence of PNI after THA was consistent with previous large-scale studies but may under-represent the true incidence because of undercoding inherent in large database studies. Previous spine disorder, chronic diabetes, younger age, and in-hospital postoperative complications all increased the risk of PNI. This study can help health-care providers and systems identify patients at higher risk of this serious complication.

Femoral nerve palsy following primary total hip arthroplasty with the direct anterior approach

Nerve palsy following total hip arthroplasty (THA) can have a serious effect on a patient`s functional prognosis and on cost-effectiveness, and it is the leading cause of THA-associated medical litigation. However, only a few studies focus on femoral nerve palsy (FNP) following THA with the direct anterior approach (DAA). Moreover, several studies have reported that THA with DAA may result in higher complication rates, particularly during the so-called ‘learning-curve period’ for the surgeon. This study aimed to identify the incidence of FNP following primary THA with DAA, to determine presumed etiologies through a retrospective investigation of FNP clinical courses following primary THA with DAA and to identify any relationship between the occurrence of FNP following primary THA with DAA and the surgeon’s experience of DAA. Since August 2007, DAA for primary THA was introduced in our institution. All 273 consecutive primary THAs with DAA (42 bilateral and 189 unilateral cases) between August 2007 and February 2014 were included in this study. All patients’ charts and radiographs were reviewed to identify cases with palsy and to retrieve related factors. In this study, FNP was defined as weakness of the quadriceps femoris (manual muscle test <3) with or without sensory disturbance over the anteromedial aspect of the thigh. The incidence of FNP following primary THA with DAA was 1.1% (3/273 joints). In all 3 cases, the motor deficit recovered completely within a year. Suspected causes of the palsy in the 3 cases were believed to be improper positioning of the anterior acetabular retractor, excessive leg lengthening, or unknown etiology. There was no significant relationship between palsy and surgeon’s experience of DAA. In THA with DAA for patients requiring major leg lengthening, the likelihood of FNP must be considered. To prevent FNP, the anterior acetabular retractor must be placed properly.

Tenotomy of the Gluteus Maximus in Total Hip Arthroplasty with Prevention of Sciatic Nerve Injury

The authors report a single case of complex primary hip total arthroplasty in a 34-year-old female patient with a 5.5 cm lower limb dysmetria, in whom a maximum gluteus tenotomy was performed in order to prevent sciatic nerve injury. The surgery was performed under electroneurophysiological monitoring of the fibular and tibial branches of the sciatic nerve, collecting pretenotomy, posttenotomy, and postarthroplasty reduction data. The findings demonstrate that the maximum gluteus tenotomy improved the motor response of the fibular component of the sciatic nerve.

Total Hip Arthroplasty for Posttraumatic Conditions

Posttraumatic arthritis accounts for a notable share of secondary osteoarthritis about the hip joint. Compared with total hip arthroplasty for primary osteoarthritis or inflammatory arthritis, total hip arthroplasty for posttraumatic arthritis offers greater technical challenges because of bone deformities and retained implants. Careful preoperative evaluation is necessary to prepare the approach, hardware removal strategy, and implants necessary to address bone deficiencies. Although arthroplasty is a highly successful procedure for posttraumatic arthritis, the results are less favorable than surgery for primary osteoarthritis. It is associated with a higher incidence of intraoperative and postoperative complications, including periprosthetic fractures, infection, instability, and decreased survivorship.

Effect of surgical approach for contralateral side hip arthroplasty in below knee amputees: a retrospective cohort study

Background

The gluteus medius muscle plays a very important role in the stability of the gait, especially in patients with amputation of the lower limbs. Therefore, choosing the appropriate type of approach for hip arthroplasty is very important. Hence, this study aimed to compare the outcomes and complications between the anterolateral approach (ALA) and posterior approach (PA) for hip arthroplasty in patients with contralateral below knee amputation.

Methods

From January 1999 to November 2014, 67 patients who underwent hip arthroplasty with contralateral below knee amputation were retrospectively analyzed. The study subjects were divided into two groups: the PA group (33 cases) and the ALA group (34 cases). The results of the clinical functional recovery with Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Harris Hip Score, and activity of daily living scale were compared between the two groups. During the follow-up period, complications related to gait such as fall, dislocation, and periprosthetic fractures (PPFs) were investigated.

Results

The Harris Hip Score (p = 0.024) and the activity of the daily living scale (p = 0.043) of the ALA group were significantly lower at 3 months compared to the PA group, but no significant difference was observed between the two groups from 6 months postoperatively to the last follow-up. The WOMAC score was not significantly different between the two groups. Within 3 months after surgery, falls occurred in 3 cases in the PA group and in 11 cases in the ALA group (p = 0.019) Dislocation and PPF were caused by prosthesis-related trauma. Two dislocations and 1 PPF occurred 8 years postoperatively in the PA group. PPF occurred in 3 patients in the ALA group, of which 2 occurred within 3 months after surgery.

Conclusion

Orthopedic surgeons should pay particular attention in patients with hip arthroplasty on the contralateral side hip who had below knee amputation because functional recovery is delayed until 3 months after ALA compared with PA.

Distal peroneal nerve decompression after sciatic nerve injury secondary to total hip arthroplasty

OBJECTIVE The sciatic nerve, particularly its peroneal division, is at risk for injury during total hip arthroplasty (THA), especially when a posterior approach is used. The majority of the morbidity results from the loss of peroneal nerve-innervated muscle function. Approximately one-third of patients recover spontaneously. The objectives of this study were to report the outcomes of distal decompression of the peroneal nerve at the fibular tunnel following sciatic nerve injury secondary to THA and to attempt to identify predictors of a positive surgical outcome. METHODS A retrospective study of all patients who underwent peroneal decompression for the indication of sciatic nerve injury following THA at the Mayo Clinic or Washington University School of Medicine in St. Louis was performed. Patients with less than 6 months of postoperative follow-up were excluded. The primary outcome was dorsiflexion strength at latest follow-up. Univariate and multivariate logistic regression analyses were performed to assess the ability of the independent variables to predict a good surgical outcome. RESULTS The total included cohort consisted of 37 patients. The median preoperative dorsiflexion grade at the time of peroneal decompression was 0. Dorsiflexion at latest follow-up was Medical Research Council (MRC) ≥ 3 for 24 (65%) patients. Dorsiflexion recovered to MRC ≥ 4- for 15 (41%) patients. In multivariate logistic regression analysis, motor unit potentials in the tibialis anterior (OR 19.84, 95% CI 2.44-364.05; p = 0.004) and in the peroneus longus (OR 8.68, 95% CI 1.05-135.53; p = 0.04) on preoperative electromyography were significant predictors of a good surgical outcome. CONCLUSIONS After performing peroneal nerve decompression at the fibular tunnel, 65% of the patients in this study recovered dorsiflexion strength of MRC ≥ 3 at latest follow-up, potentially representing a significant improvement over the natural history.

Risk Factors for Nerve Injury After Total Hip Arthroplasty: A Case-Control Study

BACKGROUND

Postsurgical acute nerve injury is rare but potentially devastating following total hip arthroplasty (THA). Previous literature suggests a wide range of incidence from 0.1% to 7.6%. Confirmed risk factors for these injuries remain unclear.

METHODS

THA patients at our institution who developed nerve injury during their admission for THA between January 1, 1998, and December 31, 2013, were systematically identified and matched with 2 control subjects by surgical date. Relevant patient and surgical data were obtained through review of patient charts and electronic health records. We identified potential risk factors and calculated odds ratios (OR) using a conditional logistic regression model with a parsimonious stepwise approach.

RESULTS

We identified 93 nerve injuries in 43,761 THAs (0.21%). The mean age of cases was 63 years. Adjusting for other factors in the model, patients <45 years were found to be at increased risk of developing nerve injury (OR, 7.17; P = .033). Similarly, patients with a history of tobacco use (OR, 1.90; P = .030) and a history of spinal surgery or disease (OR, 10.06; P < .001) were also associated with increased risk of nerve injury. For every 30-minute increase in surgery time after 1 hour, risk of nerve injury risk increased (OR, 1.48; P = .034). Assignment as first operative case of the morning was associated with a decreased risk of nerve injury (OR, 0.37, P = .043).

CONCLUSION

This study demonstrates that nerve injury is a rare complication following THA at our institution. We found risk factors that are possibly modifiable factors such as lumbar spine disease, smoking, and time of surgical scheduling.

Subtrochanteric shortening and uncemented arthroplasty in hips with high dislocation - a cohort study with 13-30 years follow-up

INTRODUCTION

The aim was to evaluate short- and long-term outcomes in patients with high hip dislocation operated with subtrochanteric shortening osteotomy and uncemented total hip arthroplasty.

METHODS

Sixty-five hips operated in 1986-2001, at mean age 48 years (15-79), were followed for mean 19 years (13-30).

RESULTS

At last follow up, there were two femoral and 35 acetabular revisions. Harris hip score was mean 86 (81-90) in unrevised, and 87 (82-90) in revised hips.

CONCLUSIONS

Our study shows favorable long-term results for a fully hydroxyapatite (HA) coated stem. Aseptic cup-loosening may be reduced by using better implants.

[Effectiveness of total hip arthroplasty for hip infection sequelae]

Objective

To evaluate hip function and reinfection of the patients with hip infection sequelae after total hip arthroplasty (THA) treatment.

Methods

A clinical data of 31 patients (31 hips) with hip infection sequelae, who were treated with THA between June 2010 and May 2017, was retrospectively analyzed. There were 18 males and 13 females, with an average age of 46.1 years (range, 20-71 years). There were pyogenic infection in 17 cases, tuberculous infection in 9 cases, and unknown source of infection in 5 cases. The average time from infection to cure was 13.9 months (range, 6-25 months). The average time from cure to operation was 23.4 years (range, 6-58 years) for patients with confirmed source of infection. According to Kim classification, 12 cases were rated as typeⅠ, 9 as typeⅡ, and 10 as type Ⅲ. There were 21 cases of osteoarthritis after dysplasia, 7 cases of pathologic dislocation, and 3 cases of hip ankylosis. After operation, the infection was assessed by physical signs and laboratory tests; X-ray film of the hip was taken to assess the skeletal structure of the hip and infectious lesion; the length of the lower limb was measured, and the function of the hip joint was evaluated by Harris score.

Results

All patients were followed up 10-63 months (mean, 34 months). The result of bacterial culture was negative. The incisions healed by first intention. The sciatic nerve stimulation occurred in 1 case and posterior dislocation of the joint occurred in 1 case after operation. There was no recurrence of infection and no aseptic loosening of the prosthesis. According to Harris score, the function of the hip was rated as excellent in 8 cases, good in 19 cases, and fair in 4 cases at last follow-up; and the excellent and good rate of hip joint function was 87%. X-ray films showed no patchy bone density reduction, spot hardening, or light areas. The length of affected limb was not fully equal with the unaffected limb in 5 cases, and the difference between two sides ranged from 0.4 to 1.3 cm (mean, 0.6 cm). At last follow-up, all patients had no obvious claudication or sensation of unequal length.

Conclusion

THA can obtain satisfactory hip function and has low risk of infection recurrence for the patients with hip infection sequelae, who were assessed as the hip infection in a dormant state.

Multimodality Intraoperative Neurophysiological Monitoring (IONM) in Anterior Hip Arthroscopic Repair Surgeries

Arthroscopic hip surgery is performed routinely for the treatment of various hip disorders. Leg traction during labral tear repair, femoroplasty, and acetabuloplasty for hip stabilization can stretch the peripheral nerves. This may cause temporary or permanent nerve injury. This study illustrates the benefit of utilizing multimodality Intraoperative Neurophysiological Monitoring (IONM) during hip surgical procedures.

We performed a retrospective review of 10 arthroscopic hip surgeries with neurophysiological monitoring at one medical center. The patients consisted of six females and four males (mean age: 48.9 years). The procedures were equally divided into left and right-sided procedures. IONM setup included posterior tibial, peroneal, and femoral or saphenous nerve somatosensory evoked potentials (SSEPs), transcranial electrical motor evoked potentials (TCeMEP), train of four (TOF), and electromyography (EMG) from the lower extremities.

All patients exhibited changes in IONM data during the surgical procedure. Changes in the latency and amplitude or loss of the lower SSEPs on the surgical side occurred in 36% of the monitorable SSEPs. The surgeon instructed the team to reduce the leg lengthening by removing traction when changes were observed. The SSEPs exhibited a full recovery in 75% of the affected lower extremity SSEPs. In the two instances of nonrecovery, the SSEP responses remained increased in latency or decreased in amplitude at closing, but the waveform was intact. There were five instances of complete loss of the waveform (four in the ipsilateral leg, and one in the contralateral leg) with recovery after traction was reduced. TCeMEP changes occurred in 53% of the ipsilateral lower muscles monitored. Many of the TCeMEP changes were attributed to ischemia of the feet and could not be resolved intraoperatively.

Multimodality IONM can be a beneficial and protective tool during surgical procedures involving hip and acetabular areas. Early identification of changes in evoked potentials during hip arthroscopy surgeries can minimize post-operative neurological deficits due to peripheral nerve injury and leg ischemia.

Femoral neuropathy following direct anterior total hip arthroplasty: an anatomic review and case series†

The popularity of the direct anterior approach for total hip arthroplasty (THA) has dramatically increased in recent years. Many patients request this muscle sparing approach for the theorized benefits of quicker recovery and reduced post-operative pain. Femoral nerve injury is a rare, yet serious complication following the anterior approach for THA. During the 7-year period from 2008 to 2016, 1756 patients underwent primary THA with a direct anterior approach by a single senior surgeon for end-stage osteoarthritis. Six (0.34%) of these patients had a post-operative femoral nerve palsy. We aim to discuss anatomic considerations, risk factors, and a timeline of severity and recovery for femoral nerve palsy following direct anterior THA in six patients.

A Case Report of a Radial Nerve Palsy Following Uncomplicated Total Hip Arthroplasty

Introduction

Nerve injury is a known complication of total hip arthroplasty (THA), but it is most commonly seen in the lower extremities. There is, however, minimal discussion about the incidence of upper extremity nerve palsies, specific to the radial nerve, during THA for a patient in the lateral decubitus position. The radial nerve can be injured while in the lateral decubitus position due to poor positioning of the posterior part of the humerus onto the hard surgical table causing compression of the nerve. In THA, this is significant due to the lateral decubitus position being the primary position for the patient in posterior and lateral approaches. We report a case of radial nerve palsy following uncomplicated THA in the lateral decubitus position.

Case Report

A 49-year-old male presenting with symptoms of the left radial nerve palsy on post-operative day number one from a right (contralateral) THA. The patient has a body mass index of 22.15 and was undergoing a right THA with a posterior approach. He was placed in the lateral decubitus position with an axillary roll in place for approximately 2 h and 45 min. Occupational therapy, orthopedics, and electromyography were used to evaluate the patient in the post-operative time for his radial nerve palsy.

Conclusion

Our case report demonstrates a rare nerve palsy complication that can be associated with positioning in THA surgeries. Knowledge of this complication can be used to avoid pressure points in future THA surgeries in the lateral decubitus position.

Post-operative extra-spinal etiologies of sciatic nerve impingement

Sciatica is a highly prevalent cause of morbidity, commonly resulting from intra-spinal pathological processes. Many cases can have extra-spinal etiologies and can be clinically challenging. Certain scenarios should suggest an extra-spinal etiology, particularly total and revision hip arthroplasty, surgical hip dislocation, hip arthroscopy, and surgery in the lithotomy position. We review the post-operative clinical scenarios where sciatic neuropathy may occur, along with the pertinent imaging findings.

The distance of the femoral neurovascular bundle from the hip joint: an intraoperative guide to reduce iatrogenic injury

Background

Iatrogenic injury to the femoral neurovascular bundle is not uncommon during primary and revision total hip replacement (THR) and can result in permanent weakness, pain and poor function. Prevention of injury to these structures relies on a sound knowledge of their relationships to the hip joint.

Methods

We studied 115 consecutive hip magnetic resonance imaging (MRI) results in order to identify objective relationships between these structures and the hip joint that can be used intraoperatively.

Results

We determined that the shortest mean distances of the femoral nerve, artery and vein from the hip joint are 23.62 (standard deviation, SD = 5.44), 19.62 (SD = 4.17) and 17.47 (SD = 4.41) mm, respectively. The femoral nerve was lateral to the hip joint in 30 (55.5%) left- and 37 (60.7%) right-sided hip joints. The femoral artery was located medial to the hip joint in 28 (51.9%) left- and 34 (55.7%) right-sided hips. The femoral vein was medial to the hip joint in 52 (96.3%) left- and 58 (95.1%) right-sided hips.

Conclusion

We have identified objective relationships between the hip joint and femoral neurovascular bundle that can be used with ease intraoperatively during THR. Our data show that patients with a low body weight and the elderly may be at a higher risk of iatrogenic injury due to increased proximity of the neurovascular structures to the hip. Application of this knowledge may serve to reduce the risk of iatrogenic injury to these structures and thereby improve patient satisfaction and outcomes.

Risk Factors for the Development of Nerve Palsy Following Primary Total Hip Arthroplasty

Background:

Nerve palsy following total hip arthroplasty (THA) is a complication that worsens the functional prognosis. The present study analyzed the risk factors of nerve palsy following THA.

Methods:

The subjects of this study included 6,123 cases in which primary THA was performed under spinal anesthesia with cementless implants used in the posterolateral approach.

Results:

Fourteen cases (0.22%) developed nerve palsy following THA, all of which involved palsy of the entire peroneal nerve region. The diagnoses included osteoarthritis due to subluxation (n=6), complete hip dislocation (n=3), osteonecrosis of the femoral head (n=2), primary osteoarthritis (n=1), osteoarthritis due to trauma (n=1), and multiple osteochondromatosis (n=1). Recovery from nerve palsy was confirmed in 10 cases; the longest recovery period was three years. A univariate analysis revealed significant differences in the osteoarthritis due to subluxation, osteonecrosis of the femoral head, complete hip dislocation, body weight and body mass index. However, none of the factors remained significant in multivariate analysis. Peroneal (ischiadic) nerve palsy following THA occurred in patients with osteonecrosis of the femoral head, complete hip dislocation, low body weight and a low body mass index. However, there were no cases of nerve palsy after the introduction of THA combined with shortening osteotomy of the femur for complete hip dislocation. patients.

Conclusion:

It is necessary to pay attention to direct pressure in cases of lower body weight and lower BMI because compression of the sciatic nerve during surgery and compression of the fibular head are considered to be risk factors.

High-Riding Congenital Hip Dislocation: THA With Unilateral vs Bilateral Transverse Femoral Shortening Osteotomy

BACKGROUND

We argue that 1-stage bilaterally total hip arthroplasty (THA) could be acceptable in bilateral coxarthrosis because of high-riding developmental dysplasia of the hip (DDH).

METHODS

Sixty-nine cases (51 patients) of high-riding DDH in patients who underwent THA from 2010 to 2013 were reviewed. Patients were divided into 2 groups: unilateral (group 1) and 1-stage bilateral surgery (group 2). The clinical measurements were the visual analog scale and Harris Hip Score.

RESULTS

The average follow-up was 37.3 months for group 1 and 38.8 months for group 2. The hospital stay time was 5.2 days in group 1 and 6.2 days in group 2 (P = .334). The mean Harris Hip Score and visual analog scale score were improved significantly after surgery for both groups, and there was no statistically significant difference (P = .988). There was no difference between groups 1 and 2 in terms of complications (P = .137).

CONCLUSION

Our data confirm that 1-stage bilateral transverse osteotomy with THA is an effective method as unilateral and it does not increase the length of patients' hospital stays and features a low risk of postoperative complications in the treatment of patients with high-riding DDH.