A systematic review of peroneal nerve palsy and recovery following traumatic knee dislocation

Differential Diagnosis of "Foot Drop": Implications for Peripheral Nerve Surgery

BACKGROUND

 At least 128,000 patients in the United States each year suffer from foot drop. This is a debilitating condition, marked by the inability to dorsiflex and/or evert the affected ankle. Such patients are rendered to a lifetime of relying on an ankle-foot orthosis (AFO) for walking and nighttime to prevent an equinovarus contracture.

METHODS

 This narrative review explores the differential diagnosis of foot drop, with a particular focus on clinical presentation and recovery, whether spontaneously or through surgery.

RESULTS

 Contrary to popular belief, foot drop can be caused by more than just insult to the common peroneal nerve at the fibular head (fibular tunnel). It is a common endpoint for a diverse spectrum of nerve injuries, which may explain its relatively high prevalence. From proximal to distal, these conditions include lumbar spine nerve root damage, sciatic nerve palsy at the sciatic notch, and common peroneal nerve injury at the fibular head. Each nerve condition is marked by a unique clinical presentation, frequency, likelihood for spontaneous recovery, and cadre of peripheral nerve techniques.

CONCLUSION

 The ideal surgical technique for treating foot drop, other than neurolysis for compression, remains elusive as traditional peripheral nerve procedures have been marred by a wide spectrum of functional results. Based on a careful understanding of why past techniques have achieved limited success, we can formulate a working set of principles to help guide surgical innovation moving forward, such as fascicular nerve transfer.

Vascular Injuries in Multiligament Knee Injuries (MLKIs)

Purpose

Vascular injuries are rarely associated with severe knee injuries; nonetheless, it is imperative to efficiently detect this condition and plan for either immediate or definitive treatment at later stages. The diagnosis and management of multiligament knee injuries still present unresolved issues, particularly in the early detection of vascular issues and the sequential stabilisation of ligaments. High-energy trauma is a frequently encountered cause, however, even low-energy trauma in those who are morbidly obese might pose a significant risk. Advancements in detection and management methods have greatly decreased the occurrence of vascular complications and amputation rates over time. MLKIs after transient knee dislocations are frequently misdiagnosed for vascular injuries, underscoring the necessity for improved diagnostic techniques to avoid avoidable amputations.

Methods

This article is a new conceptual review of vascular injuries associated with MLKIs. It provides a full overview of these conditions and includes a review of the most recent literature. We have included pertinent citations from the literature, together with suggestions derived from the latest studies. This review article had additional evaluation by proficient specialists with commendable outcomes and more than a decade of expertise in surgical techniques.

Results

This article offers a detailed overview of orthopaedic management, including new definitions and summaries of the causes, evaluation of patients, clinical assessment, identification of vascular injuries, and initial management in patients with vascular impairment following major limb and joint injuries (MLKIs).

Conclusion

MLKIs (patients with lower limb ischaemia) who have vascular damage necessitate meticulous physical assessment and sophisticated treatments in order to decrease amputation rates. Prompt identification and timely treatment of vascular lesions, namely in the popliteal artery, can substantially reduce the occurrence of amputations. Emerging research suggests that there is a heightened risk in low-energy situations, particularly amongst individuals who are extremely obese. Progress in vascular intervention has led to a reduction in amputation rates, whilst the implementation of new guidelines has enhanced identification. Thorough patient assessment is essential, utilising physical examinations and imaging techniques such as Computed tomography angiography, magnetic resonance angiography (CTA or MRA) to guide treatment decisions. MRA, in particular, is capable of identifying both vascular and knee structural damage.

Level of Evidence

Level IV, Literature reviews.

Prognostic Factors for Multiligament Knee Injury Treated With Multiligament Reconstruction: Functional and Radiological Outcomes at 2 to 8 Years Postoperatively

Background

Multiligament reconstruction (MLR) has become the standard surgical approach for treating multiligament knee injuries (MLKIs).

Purpose

To identify prognostic factors for patient-reported outcome measures, return to work (RTW), return to sports, and radiographic osteoarthritis (OA) (Kellgren-Lawrence grade ≥2) after MLR for MLKI.

Study Design

Case-control study; Level of evidence 3.

Methods

Included were 52 consecutive patients (age, 35.5 ± 11 years; 75% men), with MLKI sustained between 2013 and 2019 and treated with MLR. At a mean follow-up of 3.8 ± 1.6 years, patient-reported outcome measure scores-including the International Knee Documentation Committee (IKDC), the Knee injury and Osteoarthritis Outcome Score (KOOS), the Anterior Cruciate Ligament-Return to Sport after Injury (ACL-RSI), and the 12-Item Short-Form Health Survey-RTW, return to sports, and weightbearing radiographs were obtained. A total of 20 determinants were hypothesized and tested by univariate logistic regression for binary variables or linear regression for continuous variables. Only factors identified as significant (P < .10) were entered into a multivariate logistic regression model.

Results

The prevalence of injury severity according to the Schenck knee dislocation (KD) classification was as follows: KD I (44%), KD III (36%), KD IV (10%), and KD V (10%). Increased KD grades resulted in decreased IKDC (P = .002) and all 5 KOOS subscales (P≤ .007 for all) scores. Medial meniscectomy (23%) was associated with a worse ACL-RSI score (P = .007) and RTW failure (odds ratio [OR], 36.8; P = .035). Peroneal nerve palsy (6%) was associated with a worse ACL-RSI score (P≤ .001). Radiographic OA was observed in 38%, with distribution predominantly patellofemoral (80%) and medial tibiofemoral (45%). Traumatic cartilage damage (Outerbridge grade >2 [37%]) was associated with secondary patellofemoral (OR, 10; P = .012) and medial tibiofemoral (OR, 10; P = .019) OA. Anterior cruciate ligament reconstruction failure (7%) was a risk factor for medial tibiofemoral OA (OR, 25.8; P = .006).

Conclusion

Increased Schenck KD grade, permanent peroneal nerve palsy, and irreparable medial meniscus lesions were prognostic factors for worse functional outcomes 3.8 years after MLKI was treated with MLR. Traumatic cartilage damage and anterior cruciate ligament failure were associated with the development of early OA.

No effect of dislocation status at arrival in emergency department on outcome of knee joint dislocations

PURPOSE

Knee dislocation is a rare but severe injury of the lower extremities. The aim of this study was to report on the epidemiology, diagnostics and treatment of such injuries and to identify negative predictors of clinical outcomes.

METHODS

This retrospective analysis included all knee dislocations treated at a Level I Trauma Centre in Germany between 2009 and 2021. Medical records were categorised, collected and analysed in a standardised manner. A follow-up visit 1 year after the injury focused on limitations in knee mobility.

RESULTS

A total of 120 knee dislocations were included in the study. 29.3% of patients presented to the emergency department with a dislocated joint, and 17.5% (n = 21) had a neurovascular lesion. At follow-up 12 months after the injury, 65.8% of the patients reported limitations in the range of motion, and 11.7% (n = 14) reported severe limitations in daily activities. Site infections due to surgery occurred in 3.3% of patients. Increased body weight (r = 0.294; p < 0.001 and r = 0.259; p = 0.004), an increased body mass index above 25 kg/m2 (body mass index, r = 0.296; p < 0.001 and r = 0.264; p = 0.004) and deficits in peripheral perfusion as well as sensory and motor function (r = 0.231; p = 0.040 and r = -0.192; p = 0.036) were found to be negative predictive factors for clinical outcome. For posttraumatic neurovascular injury, lack of peripheral perfusion, insufficient sensory and motor function (r = -0.683; p < 0.0001), as well as a higher Schenck grade (r = 0.320; p = 0.037), were identified as independent risk factors. The status of dislocation at the site of the accident and on arrival at the emergency department had no impact on the outcome or neurovascular injury.

CONCLUSION

Knee dislocation is a rare injury with a high rate of severe complications such as neurovascular lesions. In particular, the initial status of neurovascular structures and injury classification showed a relevant negative correlation with the posttraumatic status of nerves and vessels. In particular, patients with these characteristics need close monitoring to prevent negative long-term consequences.

LEVEL OF EVIDENCE

Level III.

Anatomical and Technical Considerations in Fascicular Nerve Transfers for Foot Drop

BACKGROUND

 Foot drop is the common endpoint for a diverse set of nerve injuries, affecting over 128,000 in the United States each year. The level of injury, finite pace of regeneration, and/ exponential decay in the percentage of motor end-plates reinnervated over time may explain the limited success with natural recovery. Past nerve techniques have also been met with limited success.

METHODS

 This narrative review explores why past nerve techniques have failed to correct foot drop.

RESULTS

 Previously described nerve transfer techniques suffer from incompletely balancing the foot and ankle, poor donor-target nerve synergy, and/or not effectively bypassing the wide and oftentimes underappreciated zone of injury. For maximal stability, one should look to balance the foot in both dorsiflexion and eversion. Detailed descriptions and illustrations of the branching anatomy for the peroneal and tibial nerves are provided, with specific application to nerve transfer reconstruction.

CONCLUSION

 Based on an understanding of why past nerve techniques have failed to correct foot drop, a set of surgical principles can be codified to optimize functional outcomes. A surgical technique should be versatile enough to address foot drop from any of the three common pathways of injury (lumbar spine, sciatic nerve, and common peroneal nerve). With increasing familiarity using this once poorly understood anatomical region, limitations with past nerve transfer techniques may be overcome.

Functional outcomes of different surgical treatments for common peroneal nerve injuries: a retrospective comparative study

BACKGROUND

This study aims to assess the recovery patterns and factors influencing outcomes in patients with common peroneal nerve (CPN) injury.

METHODS

This retrospective study included 45 patients with CPN injuries treated between 2009 and 2019 in Jing'an District Central Hospital. The surgical interventions were categorized into three groups: neurolysis (group A; n = 34 patients), nerve repair (group B; n = 5 patients) and tendon transfer (group C; n = 6 patients). Preoperative and postoperative sensorimotor functions were evaluated using the British Medical Research Council grading system. The outcome of measures included the numeric rating scale, walking ability, numbness and satisfaction. Receiver operating characteristic (ROC) curve analysis was utilized to determine the optimal time interval between injury and surgery for predicting postoperative foot dorsiflexion function, toe dorsiflexion function, and sensory function.

RESULTS

Surgical interventions led to improvements in foot dorsiflexion strength in all patient groups, enabling most to regain independent walking ability. Group A (underwent neurolysis) had significant sensory function restoration (P < 0.001), and three patients in Group B (underwent nerve repair) had sensory improvements. ROC analysis revealed that the optimal time interval for achieving M3 foot dorsiflexion recovery was 9.5 months, with an area under the curve (AUC) of 0.871 (95% CI = 0.661-1.000, P = 0.040). For M4 foot dorsiflexion recovery, the optimal cut-off was 5.5 months, with an AUC of 0.785 (95% CI = 0.575-0.995, P = 0.020). When using M3 toe dorsiflexion recovery or S4 sensory function recovery as the gold standard, the optimal cut-off remained at 5.5 months, with AUCs of 0.768 (95% CI = 0.582-0.953, P = 0.025) and 0.853 (95% CI = 0.693-1.000, P = 0.001), respectively.

CONCLUSIONS

Our study highlights the importance of early surgical intervention in CPN injury recovery, with optimal outcomes achieved when surgery is performed within 5.5 to 9.5 months post-injury. These findings provide guidance for clinicians in tailoring treatment plans to the specific characteristics and requirements of CPN injury patients.

German S2e-Guideline "Knee Dislocation"

Knee dislocation is a devastating form of multiligament injury of the knee. Due to its high complexity, there is a large number of different diagnostic and treatment strategies. With the aim of providing evidence-based treatment recommendations, the S2e guideline on knee dislocation is aimed at all professional groups involved in diagnostics and therapy (orthopaedic and trauma surgeons, physiotherapists, outpatient/inpatient surgeons, sports physicians, etc.) as well as those affected (patients with knee dislocation) and service providers (health insurance companies, pension insurance companies). In addition to the presentation of conceptual differences between the injury entities, this includes the special features of diagnostic testing, options for conservative and surgical therapy as well as aspects of follow-up treatment - against the background of the interdisciplinary treatment approach to a severe knee injury.

[Treatment of acute knee dislocations]

A knee dislocation is a serious injury involving at least two of the four major ligamentous stabilizers of the knee. This injury results in multidirectional knee instability. In dislocation of the knee the popliteal artery and the peroneal nerve can also be damaged. Dislocations with vascular involvement are potentially threatening injuries of the lower extremities. The diagnosis of knee dislocation can be difficult due to a high rate of spontaneous reduction at the initial examination. Knee dislocations are rare and mainly occur in young men. They are mostly caused by high-energy trauma; however, they can also be caused by low-energy injuries. Obesity increases the risk of knee dislocations. The classification of a knee dislocation is based on the anatomical structures involved and the direction of dislocation. The acute treatment includes reduction and stabilization measures. Associated injuries, such as vascular, nerve, extensor mechanism and cartilage injuries as well as fractures and meniscal injuries can influence the treatment approach and the outcome. The definitive surgical treatment depends on the severity of the injury and can include ligament reconstruction or repair with bracing. The aftercare should be individually adapted with the aim to restore knee joint stability and function. Complications such as arthrofibrosis, peroneal nerve palsy, compartment syndrome, postoperative infection and recurrent instability can occur. In the long term, patients have an increased risk for the development of symptomatic osteoarthritis.

[Multiligament instabilities of the knee in sports injuries : An update of the Hamburg concept]

BACKGROUND

Knee dislocation (KD) is a rare but severe injury of the knee joint, with a high rate of concomitant neurovascular injuries. The severity of the ligamentous injury, which is classified according to the Schenck classification, the mechanism of injury, concomitant injuries and individual factors determine the treatment strategy in KD.

TREATMENT STRATEGY

Furthermore, a clear differentiation between high-velocity (HV) and low-velocity (LV) injuries is necessary. Generally, surgical treatment within 7-10 days should be aspired. Herein, the one-stage hybrid treatment using augmented ligament sutures (ligament bracing) in combination with primary ligament reconstruction (posterolateral and ACL) leads to very good functional results in the mid-term. Ultra-low-velocity (ULV) dislocations and those with concomitant peroneal lesions require a modified approach, due to a limited prognosis. During rehabilitation, the individual progress must be closely monitored and follow an early functional approach. In approximately 20% of all cases, early arthroscopic arthrolysis shows a high success rate.

Common peroneal nerve injury after tibial plateau fractures: A case series

Introduction

Common peroneal nerve (CPN) injury is a rare but significant complication of knee trauma. Given its low incidence, there is limited published evidence, but reports have shown dislocations and fractures associated with varus deformity are more likely to injure the nerve, causing foot drop. This study aims to document the incidence and outcome of CPN palsy in tibial plateau fractures (TPF).

Methods

We reviewed 746 cases of tibial plateau fractures treated between 2011 and 2020. We analysed patients' demographics, injury mechanisms, clinical course, and complications, and identified those with CPN palsies. Fractures were classified using the Schatzker, Luo and AO/OTA systems. The details of the CPN injury, including nerve conduction studies, duration of symptoms and outcome were recorded.

Results

We identified 11 patients who had concurrent TPFs and CPN palsies, an overall incidence of 1.47 %. Most fractures involved the medial column (n = 9), with the C3 fragmentary TPF pattern being the most common (n = 4). The incidence of CPN injury was higher in medial fractures (5 %) and bicondylar fractures (3 %). We also found that most patients (n = 9) recovered full neurological function within 2 years.

Discussion

This is the first study looking at a patient cohort sustaining concurrent TPFs and CPN injuries. It is a rare complication but should be looked for in high-risk medial and bicondylar fractures. We found that prognosis is better in TPF-associated CPN palsy than in other knee trauma, and that the majority of patients can expect a full recovery of nerve function.

Vascular Injury After Knee Dislocation: A Meta-Analysis Update

INTRODUCTION

Multisystem injuries affecting vasculature and nerves can be detrimental sequelae of knee dislocations (KDs). The purpose of this study was to provide an update of the current literature since the conducted search used in the publication of Medina et al on May 3, 2013, to evaluate (1) the frequency of vascular and neurologic injury after KD, (2) the frequency with which surgical intervention was conducted for vascular injury in this setting, and (3) the frequency with which each imaging modality was used to detect vascular injury.

METHODS

A two-author screening process was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the MEDLINE database. Frequency of vascular injury, surgical intervention, and amputation after KD were analyzed. Diagnostic modalities used in the acute-care setting were also evaluated.

RESULTS

Nineteen articles were analyzed for a total of 37,087 KDs. Of these, 10.7% sustained vascular injuries and 19.6% sustained nerve injuries. Overall, 62.2% of patients with vascular injury underwent surgical repair and 2.2% limbs resulted in amputation. Angiography was the most frequently used diagnostic modality (91.7%).

DISCUSSION

This review updates our understanding on the clinical implications of KDs including frequency of vascular injury (10.7%), amputation (2.2%), and nerve injuries (19.6%). Compared with prior literature, there was an increased prevalence of KD1 (32.4%) and lateral KDs (80.4%). Most vascular injuries after KD undergo surgical repair (62.2%).

Multiligamentous Knee Injuries: Acute Management, Associated Injuries, and Anticipated Return to Activity

Multiligamentous knee injuries (MLKIs) are devastating injuries. The energy and severity of these injuries encompass a wide range from low-energy single-joint mechanisms to high-energy polytrauma settings. Currently, there is no consensus on surgical treatment approach, surgical timing, or the return to preinjury activity levels after injury. There does appear to be a difference in the rate of return to activity and level of activity based on whether the injury was sustained during sport, in a trauma setting, or while on active military duty. The purpose of this descriptive review was to summarize current concepts related to (1) the acute management of MLKIs; (2) the effect of concomitant neurovascular, meniscal, and chondral injury on MLKI outcomes; (3) the effect of surgical versus nonsurgical treatment of MLKI on outcomes; and (4) rates and predictors of return to sport, work, and active military service after an MLKI.

Relationship Between Peroneal Nerve and Anterior Cruciate Ligament Involvement in Multiligamentous Knee Injury: A Multicenter Study

INTRODUCTION

Peroneal nerve injuries are rare injuries and usually associated with multiligamentous knee injuries (MLKIs) involving one or both cruciate ligaments. The purpose of our study was to perform a multicenter retrospective cohort analysis to examine the rates of peroneal nerve injuries and to see whether a peroneal nerve injury was suggestive of a particular injury pattern.

METHODS

A retrospective chart review was conducted in patients who were diagnosed with MLKI at two level I trauma centers from January 2001 to March 2021. MLKIs were defined as complete injuries to two or more knee ligaments that required surgical reconstruction or repair. Peroneal nerve injury was clinically diagnosed in these patients by the attending orthopaedic surgeon. Radiographs, advanced imaging, and surgical characteristics were obtained through a chart review.

RESULTS

Overall, 221 patients were included in this study. The mean age was 35.9 years, and 72.9% of the population was male. Overall, the incidence of clinical peroneal nerve injury was 19.5% (43 patients). One hundred percent of the patients with peroneal nerve injury had a posterolateral corner injury. Among patients with peroneal nerve injury, 95.3% had a complete anterior cruciate ligament (ACL) rupture as compared with 4.7% of the patients who presented with an intact ACL. There was 4.4 times of greater relative risk of peroneal nerve injury in the MLKI with ACL tear group compared with the MLKI without an ACL tear group. No statistical difference was observed in age, sex, or body mass index between patients experiencing peroneal nerve injuries and those who did not.

CONCLUSION

The rate of ACL involvement in patients presenting with a traumatic peroneal nerve palsy is exceptionally high, whereas the chance of having a spared ACL is exceptionally low. More than 90% of the patients presenting with a nerve palsy will have sustained, at the least, an ACL and posterolateral corner injury.

LEVEL OF EVIDENCE

IV, Case Series.

Common peroneal nerve rupture with multiple ligament knee injury: A case report

In peroneal nerve palsy with closed knee injury, most of the case improves by follow-up. We present a case of peroneal nerve rupture with closed multiple ligament knee injury, requiring nerve transplantation. In multiple ligament knee injury, it is necessary to consider the possibility of peroneal nerve rupture.

Five-year outcomes of trauma-specific function in patients after acute blunt popliteal artery injury: a matched cohort analysis

BACKGROUND

Few studies focus on the trauma-specific functional outcomes after surgical revascularization and risk factors contributing to poor outcomes in patients with acute blunt popliteal artery injury (PAI). The objective of this study was to investigate the long-term trauma-specific functional outcomes in patients with acute blunt PAI and identify the associated risk factors.

METHODS

There were 36 patients with acute blunt PAI who require surgical revascularization at a national trauma center of West China Hospital of Sichuan University between March 2010 and April 2019. After propensity matching, each patient was matched to one patient who did not have a concomitant vascular injury in control cohort. Functional outcomes were assessed with trauma-specific functional scores, physical examination of range of motion, nerve functional status and knee stability. A logistics regression model was established to determine the independent risk factors.

RESULTS

The 5-year (range 2-10 years) follow-up showed that 22 patients (22/36, 61.1%) had functional deficit due to limited activity or chronic neurological symptoms. Patients in vascular cohort had significantly decreased FIM score and AHFS score compared with matched patients without vascular involvement (P = 0.003 and P < 0.001), whereas there was no statistically significant difference in KSS (P = 0.136). Spearman correlation analysis of functional scores in vascular cohort showed that the FIM score was positively correlated with AHFS score (r = 0.926, P < 0.001), but not correlated with the KSS (r =  - 0.007, P = 0.967). Additionally, there was significant difference in the range of motion of ankle between two groups (P < 0.001 and P = 0.034). Logistic regression analysis further demonstrated nerve injuries and compartment syndrome were risk factors for poor ankle function after surgery (OR 22.580, P = 0.036 and OR 12.674, P = 0.041).

CONCLUSION

Most patients who sustained blunt PAI had significant functional deficit associated with limited activity and chronic neurological symptoms of ankle and foot, and poor functional outcomes were related to nerve injury and compartment syndrome. Therefore, early and effective decompression for compartment syndrome remains the only potentially modifiable risk factor for improving functional outcomes following PAI.

Minimally Invasive Surgical Approach for Open Common Peroneal Nerve Neurolysis in the Setting of Previous Posterior Schwannoma Removal

The common peroneal nerve (CPN) runs laterally around the fibular neck and enters the peroneal tunnel, where it divides into the deep, superficial, and recurrent peroneal nerves. CPN entrapment is the most common neuropathy of the lower extremity and is vulnerable at the fibular neck because of its superficial location. Schwannomas are benign, encapsulated tumors of the nerve sheath that can occur sporadically or in cases of neurocutaneous conditions, such neurofibromatosis type 2. In cases with compressive neuropathy resulting in significant or progressive motor loss, decompression and neurolysis should be attempted. We present a technical note for the treatment of CPN compressive neuropathy in the setting of a previous ipsilateral schwannoma removal with a minimally invasive surgical approach and neurolysis of the CPN at the fibular neck.

Transfer of Soleus Muscular Branch of Tibial Nerve to Deep Fibular Nerve to Repair Foot Drop After Common Peroneal Nerve Injury: A Retrospective Study

Objective

Common peroneal nerve (CPN) injury that leads to foot drop is difficult to manage and treat. We present a new strategy for management of foot drop after CPN injury. The soleus muscular branch of the tibial nerve is directly transferred to the deep fibular nerve, providing partial restoration of motor function.

Methods

We retrospectively reviewed eight patients treated for CPN injury between 2017 and 2019. The soleus muscular branch of the tibial nerve was transferred to the deep fibular nerve to repair foot drop. Electrophysiology was conducted, and motor function was assessed. Motor function was evaluated by measuring leg muscle strength during ankle dorsiflexion using the British Medical Research Council (BMRC) grading system and electromyography (EMG).

Results

In 10–15 months postoperatively, EMG revealed newly appearing electrical potentials in the tibialis anterior, extensor hallucis longus, and extensor toe longus muscle (N = 7). Two patients achieved BMRC grade of M4 for ankle dorsiflexion, 2 patients achieved M3, 1 patient achieved M2, and 2 patients achieved M1. Four patients showed good functional recovery after surgery and could walk and participate in activities without ankle-foot orthotics.

Conclusion

Surgical transfer of the soleus muscular branch of the tibial nerve to the deep fibular nerve after CPN injury provides variable improvements in ankle dorsiflexion strength. Despite variable strength gains, 50% of patients achieved BMRC M3 or greater motor recovery, which enabled them to walk without assistive devices.

Postoperative Rehabilitation and Return to Sport Following Multiligament Knee Reconstruction

Multiligament knee injuries (MLKIs) are debilitating injuries that increasingly occur in young athletes. Return to sport (RTS) has historically been considered unlikely due to the severity of these injuries. Reporting in the literature regarding objective outcomes following MLKI, including RTS, is lacking, as are clear protocols for both rehabilitation progressions and RTS testing. RTS following MLKI is a complex process that requires an extended recovery duration compared to other surgery types. Progressions through postoperative rehabilitation and RTS should be thoughtful, gradual, and criterion based. After effective anatomic reconstruction to restore joint stability, objective measures of recovery including range of motion, strength, movement quality, power, and overall conditioning guide decision-making throughout the recovery process. It is important to frame the recovery process of the athlete in the context of the severity of their injury, as it is typically slower and less linear. Improved reporting on objective outcomes will enhance our understanding of recovery expectations within this population by highlighting persistent deficits that may interfere with a full recovery, including RTS.

Knee joint dislocation: overview and current concepts

Knee joint dislocation is a relatively uncommon injury but its management is important because of the associated high risk of vascular, neurological and multi-ligamentous knee injuries. Clinicians must be aware that not all knee dislocations are diagnosed on plain X-rays; a high index of suspicion is required based on clinical evaluation. Multidisciplinary specialist care is required in all cases to achieve best outcomes. Early one-stage or multiple staged ligament repair and reconstruction offer better outcomes, but most patients have some long-term functional limitation. This article provides insights into the epidemiology and management of this injury and its devastating effects.

Routine knee MRI: how common are peripheral nerve abnormalities, and why does it matter?

OBJECTIVE

To evaluate the frequency, MRI appearance, and clinical significance of peripheral nerve abnormalities encountered on routine knee MRI.

MATERIALS AND METHODS

A retrospective review was performed to identify consecutive patients who underwent routine knee MRI from March 2015-2018 and had peripheral nerve abnormalities. MRIs were reviewed for the presence of tibial (TN) and common peroneal nerve (CPN) abnormalities (including hyperintensity, bulbous enlargement, discontinuity, architectural distortion, skeletal muscle denervation). The presence or absence of concomitant meniscal, cruciate, and collateral ligament tears was documented. Patient demographics and clinical outcomes were recorded. Descriptive statistics were reported.

RESULTS

The search yielded 8125 MRIs, of which 50 knee MRIs (patient age (years): 44 + 19) had peripheral nerve abnormalities (hyperintensity (TN: 30%(15/50), CPN: 80%(40/50)), bulbous enlargement (TN: 10%(5/50), CPN: 30%(15/50)), discontinuity (TN: 0, CPN: 4%(2/50)), architectural distortion (TN: 4%(2/50), CPN: 18%(9/50)), and skeletal muscle denervation (TN: 14%(7/50), CPN: 28%(14/50)). Medial meniscus (TN: 12% (6/50), CPN: 36%(18/50)), ACL (TN: 4%(2/50), CPN: 32%(16/50)), PCL (TN: 2%(1/50), CPN: 20%(10/50)), and lateral meniscus (TN: 12%(6/50), CPN: 24%(12/50)) tears were frequently present. Of these, 32% (16/50) were treated for peripheral nerve injury (PNI), characterized as high-grade (n = 7/16) or low-grade (n = 9/16). Nerve discontinuity, architectural distortion, and denervation were encountered more in high-grade PNI than low-grade PNI. Five patients were recalled for follow-up imaging and operative management was performed in 36% of cases (18/50).

CONCLUSION

Although uncommon (frequency = 0.6%), peripheral nerve abnormalities (CPN more common than TN) are encountered on routine knee MRI and affect patient management, with 36% requiring surgical treatment.

Distal biceps femoris avulsions: Associated injuries and neurological sequelae

BACKGROUND

The aim of this study was to describe associated injuries in cases of distal biceps femoris avulsions (DBFA) as well as the incidence of neurological injury and radiographic abnormalities of the common peroneal nerve (CPN).

METHODS

A retrospective chart review was conducted of patients presenting to our office or trauma center with DBFA injuries. Demographic data was obtained as well as mechanism of injury. Assessment of concomitant injuries and presence of neurologic injury was completed via chart review and magnetic resonance imaging (MRI) review. The CPN was evaluated for signs of displacement or neuritis.

RESULTS

Sixteen patients were identified (mean age-at-injury 28.6 years, 87.5% male) with DBFA. Three patients (18.8%) sustained their injuries secondary to high energy trauma while 13 (81.3%) had injuries secondary to lower energy trauma. Nine patients (56.3%) initially presented with CPN palsy. All patients presenting with CPN palsy of any kind were found to have a displaced CPN on MRI and no patient with a normal nerve course had a CPN palsy.

CONCLUSIONS

This case series demonstrates a strong association between DBFA and CPN palsy as well as multi-ligamentous knee injury (MLKI). These injuries have a higher rate of CPN palsy than that typically reported for MLKI. Furthermore, these findings suggest that CPN displacement on MRI may be a clinically significant indicator of nerve injury. LOE: IV.

Controversies in acute multiligamentary knee injuries (MLKI)

Multiligament injuries of the knee (MLKI), remain an infrequent pathology especially in developed countries compared to mono-ligament lesions. In Colombia, MLKI is frequent due to the high accident rate on motorcycles. In the city of Bogota alone, about 160 motorcycle accidents have been estimated daily, being one of the cities that proportionately use this means of transport less compared to small cities. The term MLKI, include all ruptures of two or more major ligaments and therefore it has a broad spectrum of clinical presentation which creates a great challenge for the orthopedists and the surgeons envolved in this topic. The literature is rich in studies level IV but very poor in level I and level II, which generates controversies and little consensus in the diagnosis and treatment of this pathology. However there has been a gradual and better understanding of all factors involved in the treatment of MLKI that has improved the functional results of these knees in our patients, in fact we currently are more precise to achieve accurate diagnosis, evolved from not surgical approach to operate most, applying new anatomical and biomechanical concepts, with specialized and skill surgical techniques with more stable and biocompatible fixation implants, which allow in most cases to initiate an early integral rehabilitation program. Nevertheless due to the complexity and severity of the lesions, in some patients the functional results are poor. The goal of this revision is to identify the most frequent controversies in the diagnosis and treatment of MLKI, defining which of them are agreed according to what is reported in the literature and share some concepts based from the experience of more than 25 years of the senior author (MM) in the management of these injuries. LEVEL OF EVIDENCE: V - Expert Opinion.

The outcomes of one-stage treatment for multiple knee ligament injuries combined with extensor apparatus rupture

Background

Multiple knee ligament injuries combined with extensor apparatus rupture are serious and complex knee injuries that are rare in clinical practice. The management is extremely challenging and controversial.

The aim of this study is to describe a patient collective with multiple knee ligament injuries combined with extensor apparatus injuries in detail and to report the mid-term outcomes of a one-stage surgical treatment regarding subjective outcome scores, complications, knee instability, and ROM.

Methods

Eleven of 425 patients with multiple knee ligament injuries combined with extensor apparatus injuries admitted to our hospital were reviewed from July 2008 to May 2017. All patients underwent one-stage repair and reconstruction of multiple knee ligaments and extensor apparatus. The Lysholm knee score and the International Knee Documentation Committee (IKDC) score were adopted to evaluate the surgical effect preoperatively and at a minimum of 2 years’ follow-up. Clinical data, including range of motion and knee stability, were also recorded at the final follow-up.

Results

Ten patients were followed up with a mean time of 40 (range, 24–60) months. At the last follow-up, 8 patients had joint flexion range of motion greater than or equal to120 degrees, 2 patients had joint flexion range of motion of 100–120 degrees, and 1 patient had active knee extension limitation of 5 degrees. Stress radiographs showed that the mean differences in posterior displacement were reduced from 10.8 ± 3.0 mm preoperatively to 2.0 ± 2.5 mm at the last follow-up. There were significant improvements in stress radiographs from pre- to postoperative states for all patients with multiple knee ligament injuries. The Lysholm score ranged from 85 to 96, with a mean of 92.1 (compared with 33 before surgery, P < 0.05). The final IKDC scores were A in 2 patients (20%), B in 7 (70%), and C in 1 (10%). Nine of the 10 patients (90%) returned to their former activity level.

Conclusion

Multiple knee ligament injuries combined with extensor apparatus rupture are rare. Single-stage management of the repair and reconstruction of multiple knee ligaments and extensor apparatus with proper rehabilitation is an effective and reliable procedure to restore knee stability and function.

Level of evidence

Level IV, therapeutic case series.

Open tibia plateau fracture with intra-osseous dislocation of the patella and quadriceps tendon rupture: a case report

Background

Both tibial plateau fractures and extensor apparatus injuries are serious injuries to the knee joint that generally do not occur in the same patient. We report a rare case of open tibial plateau fracture combined with quadriceps tendon rupture and complete displacement of the patella into the tibial plateau fracture.

Case presentation

The case involved a male who was 19 years old who had been in a motorcycle accident. The patient was admitted to our department with an open tibial plateau fracture 3 h post-injury. X-ray showed a tibial plateau fracture and complete displacement of the patella into the tibial plateau. CT showed an avulsion fracture in the patella and tibial intercondylar eminence. Concomitant quadriceps tendon injury and both anterior and posterior cruciate ligament tibial insertion avulsion fractures were considered. The operative findings of emergency surgery confirmed our preoperative diagnosis. Single-stage quadriceps tendon repair and ORIF for the tibial plateau fracture were performed. Satisfactory restoration of function was acquired at the last follow up.

Conclusion

The most difficult aspect of this case was the determination of the cause of the intra-osseous dislocation of the patella into the tibial plateau. The most likely mechanism of the injury may be that the patient experienced transient posterior dislocation of the knee during the injury. Rupture of the quadriceps tendon should be considered with posterior dislocation of the knee, and the patella was pushed into the tibial plateau fracture by force after the rupture of the quadriceps tendon.

Management of multiligament knee injuries

Up to 18% of multiligament knee injuries (MLKI) have an associated vascular injury.All MLKI should be assessed using the ankle brachial pressure index (ABPI) with selective arteriography if ABPI is < 0.9.An ischaemic limb following knee dislocation must be taken to the operating theatre immediately for stabilization and re-vascularization.Partial common peroneal nerve (CPN) injury following MLKI has better recovery than complete palsy.Posterior tibial tendon transfer is offered to patients with complete CPN palsy if there is no recovery at six months.Operative treatment with acute or staged reconstructions provides the best outcome in MLKI.Effective repair can only be performed within three weeks of injury.There is no difference between repair and reconstruction of medial collateral ligament and posteromedial corner.Posterolateral corner reconstruction has a lower failure rate than repair.Early mobilization following MLKI surgery results in fewer range-of-motion deficits. Cite this article: EFORT Open Rev 2020;5:145-155. DOI: 10.1302/2058-5241.5.190012.

Evaluation and Management of Knee Dislocation in the Emergency Department

BACKGROUND

Knee dislocations are a potentially limb-threatening injury, and it is essential that emergency medicine clinicians are aware of them.

OBJECTIVE

This article provides a review of the diagnosis and management of knee dislocation for the emergency provider.

DISCUSSION

Knee dislocations are uncommon injuries with the potential for significant morbidity. A thorough history and examination are important, because 50% of dislocations may have reduced before arrival to the emergency department. Knee dislocations should be quickly reduced in the emergency department setting. The presence of equal pulses does not exclude vascular injury, and all patients should undergo serial vascular examinations and evaluation with ankle-brachial indices. Those with abnormal ankle-brachial indices should receive computed tomographic angiography. Radiographs are important to identify any fractures, while magnetic resonance imaging may be deferred until after admission.

CONCLUSION

Knee dislocation is a potentially dangerous medical condition requiring rapid diagnosis and management. It is essential for emergency clinicians to know how to diagnose and treat this disorder.

Subacute High-Energy Traumatic Knee Dislocation in an Ambulatory Patient: A Case Report

CASE

A 62-year-old man presented with a posterolateral knee dislocation sustained in a motorcycle collision initially managed nonsurgically. His treatment was complicated by recurrent dislocation from noncompliance with bracing and weight-bearing restrictions and by comorbidities including peripheral artery disease, type 2 diabetes, and heavy smoking and drinking. He was treated with a multiplanar knee-spanning external fixator and patellar tendon repair without further ligamentous reconstruction. This treatment provided a stable, functional knee with minimal pain.

CONCLUSIONS

In this complex, noncompliant patient with a subacute knee dislocation, knee-spanning biplanar external fixation and patellar tendon repair without ligament reconstruction were crucial in achieving a satisfactory outcome.

CT can stratify patients as low risk for tibial neuropathy following a talus fracture

OBJECTIVE

Determine the incidence of tibial neuropathy following talus fractures and CT's ability to stratify patients at risk for developing post-traumatic neuropathy.

MATERIALS AND METHODS

In this IRB-approved retrospective analysis, 71 talus fractures and 8 contralateral control ankle CTs were reviewed by one observer blinded to clinical information. CT evidence suggestive of tibial neurovascular bundle injury included nerve displacement, perineural fat effacement/edema, and bone touching nerve. The association between these CT findings and clinically evident tibial neuropathy was analyzed. A semi-quantitative likelihood score was assigned based on the degree of the CT findings around the nerve. Interobserver agreement was calculated between 2 other readers.

RESULTS

Twenty-five percent of patients in this cohort had clinical evidence of tibial neuropathy. There was a high specificity (0.87-0.93) and negative predictive value (0.83-0.87), a moderate accuracy (0.80-0.82), but a lower sensitivity (0.33-0.56) associated with the CT findings. Among the CT findings, nerve displacement (p < 0.0001) and bone touching nerve (p = 0.01) were associated with tibial neuropathy. A likelihood score of 2-5 was associated (p = 0.007-0.015) with tibial neuropathy. The presence of tibial neuropathy and nerve recovery were not associated with hospital length of stay, while CT findings were. There was substantial agreement between the three readers: likelihood scores 2+ (k = 0.78) and 3+ (k = 0.72).

CONCLUSIONS

Tibial neuropathy occurs following talus fractures, and CT findings may help surgeons narrow down the number of patients requiring close neurological follow-up.

Lariat sign: An MRI finding associated with common peroneal nerve rupture

Traumatic knee dislocation represents a catastrophic orthopedic injury with potentially devastating vascular and neurologic injuries. We report a case of common peroneal nerve rupture sustained during a knee dislocation with novel radiographic findings that we describe as a lariat sign. At the site of rupture, the distal nerve loops back on itself forming a lasso shape or lariat. This thickened nerve's abnormal course should not be misinterpreted as a vessel.

Return to Work or Sport After Multiligament Knee Injury: A Systematic Review of 21 Studies and 524 Patients

PURPOSE

To systematically review multiligament knee injury (MLKI) outcome studies to determine overall rates of return to work or sport after MLKI and risk factors for lack of return to work or sport after MLKI.

METHODS

A search was performed of MLKI outcome studies from 1950 to March 1, 2017. Ninety-two studies were identified. All included reported return to work, return to sport, or Tegner activity scores. Rates of return to work or sport were determined for overall population and by obesity status, injury severity, and presence of peroneal nerve or vascular injury.

RESULTS

A total of 524 patients (21 studies) were included. Return to high-level sport was low (22%-33%). Return to any level of sport was 53.6% overall (178/332), with a higher rate reported in studies with all surgical patients (59.1%, 114/193 patients) versus studies with mixed surgical and nonoperative treatment (46.0%, 64/139 patients) (P = .02). Rate of return to work with little or no modifications was 62.1% (146/200) and return to any work was 88.4% (190/215). Obese patients had lower postoperative Tegner scores than a general population (obese: mean 1.7 ± 1.2; nonobese: mean 4.5 ± 1.0; P < .001). Among studies without Schenck grade IV and V injuries, return to work with no or minimal modifications (100%, 12/12 patients) was higher than studies including grade IV and V patients (66.0%, 70/106 patients) (P = .017). Return to any work was higher in studies without vascular injuries (96.3%, 105/109) versus those including them (80.2%, 85/106) (P < .001).

CONCLUSIONS

Return to sport after MLKI occurs in approximately 60% of surgically treated patients, though return to high-level sport is lower. Return to work is frequently possible after MLKI though it may require workplace or job duty modifications. Obesity, nonoperative treatment, higher injury severity, and vascular injury are associated with poorer functional outcomes.

LEVEL OF EVIDENCE

Level IV, systematic review of level III and IV studies.

The Leg Wound of King Philip II of Macedonia

Objective

King Philip II, the father of Alexander the Great, suffered a penetrating wound to the leg from a spear that left him severely handicapped. His skeletal remains represent the first and only case of an injury from ancient Greece that can be directly compared to its historical record. The objective of the study was to confirm the identity of the male occupant of Royal Tomb I in Vergina, Greece as Philip II of Macedonia by providing new evidence based on anatomical dissection and correlation with the historical description of the wounds.

Methods

Radiographs and photographs of the leg in Royal Tomb I in Vergina were examined. Anatomical dissection of a cadaver with a reconstructed wound similar to Philip’s was also completed to identify associated soft-tissue injuries.

Results

The left leg was penetrated by an object at the knee which resulted in joint diastasis, external rotation of the tibia, knee ankylosis, and formation of a granuloma around the related object. This caused massive trauma to the joint but spared the popliteal artery. This resulted in ligamentous injury as well as injury to the peroneal nerve and probably the tibial nerve, resulting in a complete palsy of those nerves.

Conclusion

This evidence exactly matches the historical sources and shows conclusively that the leg and Tomb I belong to Philip II. The anatomic and archaeologic evidence also serve as independent verification of some of the historical record of that period, better enabling scholars to judge the reliability of various texts. Furthermore, it gives invaluable information about surgical practices in ancient Greece according to Hippocratic methods and their outcomes. Finally, this sheds new light on the occupants of Royal Tomb II including the fact that the armor recovered there may have belonged to Alexander the Great.

Management of knee dislocation prior to ligament reconstruction: What is the current evidence? Update of a universal treatment algorithm

Traumatic knee dislocation is a rare but potentially limb-threatening injury. Thus proper initial diagnosis and treatment up to final ligament reconstruction are extremely important and a precondition to successful outcomes. Reports suggest that evidence-based systematic approaches lead to better results. Because of the complexity of this injury and the inhomogeneity of related literature, there are still various controversies and knowledge gaps regarding decision-making and step-sequencing in the treatment of acute multi-ligament knee injuries and knee dislocations. The use of ankle-brachial index, routine or selective angiography, braces, joint-spanning or dynamic external fixation, and the necessity of initial ligament re-fixation during acute surgery constitutes current topics of a scholarly debate. The aim of this article was to provide a comprehensive literature review bringing light into some important aspects about the initial treatment of knee dislocation (vascular injury, neural injury, immobilization techniques) and finally develop an accurate data-based universal algorithm, enabling attending physicians to become more acquainted with the management of acute knee dislocation.

An evidence-based algorithm for the management of common peroneal nerve injury associated with traumatic knee dislocation

Traumatic knee dislocation is a complex ligamentous injury that may be associated with simultaneous vascular and neurological injury.Although orthopaedic surgeons may consider CPN exploration at the time of ligament reconstruction, there is no standardised approach to the management of this complex and debilitating complication.This review focusses on published evidence of the outcomes of common peroneal nerve (CPN) injuries associated with knee dislocation, and proposes an algorithm for the management. Cite this article: Deepak Samson, Chye Yew Ng, Dominic Power. An evidence-based algorithm for the management of common peroneal nerve injury associated with traumatic knee dislocation. EFORT Open Rev 2016;1:362-367. DOI: 10.1302/2058-5241.160012.

Knee Dislocations in Sports Injuries

Knee dislocations are devastating when they occur on the athletic field or secondary to motor sports. The complexity of presentation and spectrum of treatment options makes these injuries unique and extremely challenging to even the most experienced knee surgeons. An astute appreciation of the treatment algorithm is essential to plan individualized management since no two complex knee dislocations are ever the same. Moreover, attention to detail and finesse of surgical technique are required to obtain a good functional result and ensure return to play. Over the past 10 years, our service has treated 43 competitive sportsmen with knee dislocations, and this experience forms the basis for this narrative review.