Vascular and nerve injury after knee dislocation: a systematic review

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.

Uncommon Floating Knee in a Teenager: A Case Report of Ipsilateral Physeal Fractures in Distal Femur and Proximal Tibia

INTRODUCTION

The concomitance of ipsilateral physeal fractures of the distal femur and the proximal tibia is an extremely scarce entity. It is conceptually similar to floating knee in pediatric population.

CASE REPORT

One case with this injury is reported in a 16-year-old teenager. He was treated surgically by close reduction and internal fixation. The diagnosis of the tibial fracture was initially missed and the fracture was seen on the post-operative radiographs. Orthopedic treatment was made for this injury. 2 years after, no angular deformity neither shortening of the limb were found.

CONCLUSION

These rare injuries could have serious immediate and remote complication with a considerable functional impact. The diagnosis of proximal tibia physeal fracture could be missed in the context of a concomitant more impressive distal femur fracture. The possibility of a combination of these two injuries should then be kept in mind. Anatomic reduction should be made as soon as possible using a gentle technique and attention should be given to the diagnosis of the neurovascular complications.

Surgical management of posterior knee dislocation associated with extensor apparatus rupture

OBJECTIVE

The purpose of this study was to report the clinical and functional results of patients who underwent surgical management for posterior knee dislocation associated with extensor apparatus rupture.

INTRODUCTION

Posterior knee dislocations associated with extensor apparatus ruptures are defined as rare but complicated injuries, which are difficult to return to the level of activity prior to the injury. The study demonstrated a hypothesis that good knee stability and early gain of range of motion could be achieved with deliberate design of the treatment protocol and proper application of the instruments.

METHODS

Fifteen patients with posterior knee dislocations associated with extensor apparatus ruptures were evaluated after reduction and repair of extensor apparatus. Following that, multiple-ligament reconstruction in association with use of a lateral knee-spanning external fixator was applied for at least six weeks. Ligament reconstructions were performed using allografts. Range of motion and knee stability were both measured at each follow-up evaluation at a mean time of 36months. The assessment was made using the Lysholm Knee Scoring Scale.

RESULTS

The mean Lysholm scale score was 87.6 (range 73-95), with excellent in 11 cases, good in two, and fair in two. In the final evaluation, the range of motion was a mean range of 123.4° (range 100-135).

CONCLUSION

The use of a lateral knee-spanning external fixator ensured the safety of repaired vessels, knee stability after reduction, and early rehabilitation with range of motion.

Effect of Vascular Injury on Functional Outcome in Knees with Multi-Ligament Injury: A Matched-Cohort Analysis

BACKGROUND

Multi-ligament knee injury (MLKI) associated with knee dislocation can result in vascular injury. The purpose of this study was to compare knee function after MLKI between patients with a vascular injury requiring popliteal artery bypass grafting and patients without vascular involvement. Additionally, factors associated with poor knee function in patients who had MLKI with vascular injury were evaluated.

METHODS

This retrospective study identified patients with an MLKI between 1992 and 2014. Each patient who had a concomitant vascular injury requiring bypass grafting (vascular cohort, n = 16; mean age, 30.3 years) was matched to 2 patients without a vascular injury (control cohort, n = 32; mean age, 31.4 years) on the basis of age, knee dislocation (KD) grade, and peroneal nerve status. Fifteen patients in the vascular cohort and 26 patients in the control cohort had an isolated knee injury. Functional outcomes were assessed with physical examination of range of motion and ligamentous stability as well as patient-reported outcome scores.

RESULTS

The vascular cohort had a mean Lysholm score of 62.5 points (range, 16 to 100 points) and a mean International Knee Documentation Committee (IKDC) score of 59.7 points (range, 14.9 to 100 points) at a mean (and standard deviation) of 8.3 ± 5.0 years after surgery. The control cohort had a mean Lysholm score of 86.4 points (range, 51.0 to 100.0 points) and a mean IKDC score of 83.8 points (range, 35.6 to 100.0 points) at a mean of 6.0 ± 4.0 years. The vascular cohort had significantly lower Lysholm (p = 0.001) and IKDC (p = 0.002) scores than the control cohort. A body mass index (BMI) of >30 kg/m was predictive of lower IKDC (p = 0.0009) and Lysholm (p = 0.0008) scores.

CONCLUSIONS

Patients who sustain an MLKI with an associated popliteal artery injury requiring bypass grafting have significantly lower knee function scores than patients without vascular involvement. This information can be used to help counsel patients with combined multiple ligament and popliteal artery injuries.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Uncommon Floating Knee in a Teenager: A Case Report of Ipsilateral Physeal Fractures in Distal Femur and Proximal Tibia

INTRODUCTION

The concomitance of ipsilateral physeal fractures of the distal femur and the proximal tibia is an extremely scarce entity. It is conceptually similar to floating knee in the pediatric population.

CASE REPORT

One case with this injury is reported in a 16-year-old teenager. He was treated surgically by close reduction and internal fixation. The diagnosis of the tibial fracture was initially missed, and the fracture was seen on the post-operative radiographs. Orthopedic treatment was made for this injury. 2 years after, no angular deformity neither shortening of the limb were found.

CONCLUSION

These rare injuries could have serious immediate and remote complication with a considerable functional impact. The diagnosis of proximal tibia physeal fracture could be missed in the context of a concomitant more impressive distal femur fracture. The possibility of a combination of these two injuries should then be kept in mind. Anatomic reduction should be made as soon as possible using a gentle technique, and attention should be given to the diagnosis of the neurovascular complications.

Current Concepts and Controversies in Rehabilitation After Surgery for Multiple Ligament Knee Injury

PURPOSE OF REVIEW

The purpose of this manuscript is twofold: (1) to review the literature related to rehabilitation after surgery for multiple ligament knee injury (MLKI) and after isolated surgery for the posterior cruciate ligament (PCL), posterolateral corner (PLC), and medial side of the knee and (2) to present a hierarchy of anatomic structures needing the most protection to guide rehabilitation.

RECENT FINDINGS

MLKIs continue to be a rare but devastating injury. Recent evidence indicates that clinicians may be providing too much protection from early weight bearing and range of motion, but an accelerated approach has not been rigorously tested. Consideration of the nature and quality of surgical procedures (repair and reconstruction) can help clinicians determine the structures needing the most protection during the rehabilitation period. The biomechanical literature and prior clinical experience can aid clinicians to better structure rehabilitation after surgery for MLKI and improve clinical outcome for patients.

Clinical and Functional Results of 119 Patients With Knee Dislocations

OBJECTIVES

To describe clinical results and functional outcomes of knee dislocations treated with a consistent strategy within our institution.

DESIGN

Retrospective case series.

SETTING

Level 1 trauma center.

PATIENTS

One hundred nineteen patients were treated at one institution between 2000 and 2014 for knee dislocation.

MAIN OUTCOME MEASUREMENTS

Knee range of motion, functional instability, and complications were recorded. Musculoskeletal Function Assessment (MFA) and Lysholm scores were obtained after minimum of 1 year.

RESULTS

Sixty-three early complications were noted in 36 patients (32%), with an overall amputation rate of 9.2% (8 early and 3 late amputations). Of the patients who retained their limb, 4.5% reported instability. Open knee dislocations were associated with amputation (26% vs. 1.3%, P < 0.001). Popliteal arterial injuries were associated with more amputation (31% vs. 3.2%, P = 0 < 0.001), infection (37% vs. 8%, P = 0.002), and deep venous thrombosis (32% vs. 8.8%, P = 0.014). Patients with wound infection were more likely to develop heterotopic ossification (36% vs. 9.4%, P = 0.017) and less knee motion (77.5 vs. 117 degrees P = 0.049). Knee motion improved over time for all patients with a mean arc of 86 degrees at 3 months, 109 degrees at 6 months, and 115 degrees at 12 months. An Injury Severity Score of ≥20 was associated with less knee motion (97 vs. 121 degrees P = 0.029). Mean Lysholm score was 86.7, and mean MFA score was 35.7 after mean follow-up of 90 months and 82 months, respectively.

CONCLUSIONS

Few patients (4.5%) experienced functional instability. However, early complications occurred frequently (32%) as expected, particularly in patients with open injuries and/or arterial injury. Limitations in knee motion were associated with high Injury Severity Score, infection, and heterotopic ossification. Mean knee scores were good, consistent with reasonable knee function, although MFA scores suggest a lower level of generalized function.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Demographics and Injuries Associated With Knee Dislocation: A Prospective Review of 303 Patients

Background:

Information on the incidence, injury mechanisms, ligament injury patterns, and associated injuries of knee dislocations is lacking in the literature. There is a need to characterize ligament injury patterns and associated injuries in knee dislocations to avoid missing common associated diagnoses and to plan surgical treatment.

Purpose:

To evaluate patient demographics, ligament injury patterns and associated injury patterns, and associated injuries in patients with knee dislocation.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

A total of 303 patients with knee dislocations treated at a single level 1 trauma center were followed prospectively. Injury mechanism; ligament injury patterns; associated neurovascular, meniscal, and cartilage injuries; and surgical complications were recorded. The Schenck knee dislocation classification was used to classify the ligament injury patterns.

Results:

The mean age at injury was 37.8 ± 15.3 years. Of the 303 patients included, 65% were male and 35% were female. There was an equal distribution of high-energy and low-energy injuries. Injury to 3 major ligaments was the most common, with Schenck classification type KD III-M constituting 52.4% of the injuries and KD III-L comprising 28.1%. Meniscal injuries and cartilage injuries occurred in 37.3% and 28.3% of patients, respectively. Patients with acute injuries had significantly lower odds of a cartilage injury than those with chronic injuries (odds ratio [OR], 0.28; 95% CI, 0.15-0.50; P < .001). Peroneal nerve injuries were recorded in 19.2% of patients (10.9% partial and 8.3% complete deficit), while vascular injuries were recorded in 5%. The odds of having a common peroneal nerve injury were 42 times greater (P < .001) among those with posterolateral corner injury (KD III-L) than those without. The odds for popliteal artery injury were 9 times greater (P = .001) among those with KD III-L injuries than other ligament injury types.

Conclusion:

Medial-sided bicruciate injuries were the most common injury pattern in knee dislocations. Cartilage injuries were common in chronically treated patients. There was a significant risk of peroneal nerve injury with lateral-sided injuries.

Knee Dislocation: A Case Report, Diagnostic Vascular Work-Up, and Literature Review

Knee dislocation is an uncommon, potentially limb-threatening, knee injury. Most often caused by high-velocity trauma, it can also result from low- or even ultra-low-velocity trauma. Rapid identification of the injury, reduction, and definitive management are necessary to minimize neurovascular damage. We present a case of rotatory anterolateral knee dislocation sustained during a twisting sports-related event. Special emphasis is placed on diagnosing vascular injuries associated with knee dislocations.

Bilateral knee dislocation with associated bilateral popliteal arterial injury

Tibiofemoral unilateral knee dislocations are uncommon, making bilateral dislocations even rarer injuries. Knee dislocation is considered one of the most serious injuries that can affect this joint. Associated complications such as popliteal artery injury are responsible for the important morbidity in these patients. The authors report the case of a 52-year-old man with a traumatic bilateral knee dislocation with associated bilateral popliteal arterial injury. His clinical presentation along with radiographic and angiographic findings are described. Surgical and non-surgical treatment and functional outcomes are also reported.

Acute Thrombotic Occlusion of the Popliteal Artery following Knee Dislocation: A Case Report of Management, Local Unit Practice, and a Review of the Literature

Arterial complications following traumatic knee injury are relatively rare but mandate timely recognition and treatment to avoid significant comorbidity and medicolegal ramifications. In this report we describe a case of acute thrombotic occlusion of the popliteal artery occurring after knee dislocation, successfully repaired by intimal fixation and a limited venous patch reconstruction. We present a review of local practice in screening vascular injuries following knee dislocation, aligned with a review of the literature and considerations for practice.

How sensitive and specific is 1.5 Tesla MRI for diagnosing injuries in patients with knee dislocation?

PURPOSE

The purpose of this study was to assess the sensitivity and specificity of 1.5 T magnetic resonance imaging (MRI) in diagnosing and identifying the specific injury pattern in patients with knee dislocation. The hypothesis was that the sensitivity and specificity are low in patients with posterolateral corner injury and/or PCL tear.

METHODS

A retrospective study was performed on 38 patients (m:f = 29:9, mean age ± SD 34.3 ± 14.0) with traumatic knee dislocation, who underwent 1.5 T MRI prior to surgery. MRI scans were analysed by a musculoskeletal radiologist, and the presence and type of tears to ligaments, tendons and meniscus or bone were recorded. Comparison was made with the intraoperative findings from the surgical records using the same reporting scheme. The agreement between MRI and surgical findings was assessed using kappa statistics, and the sensitivity and specificity were calculated.

RESULTS

In patients with knee dislocation, MRI was found to have low sensitivity (25-38 %) but high specificity (94-97 %) for diagnosing injury to the posterolateral corner. There was high sensitivity in the diagnosis of tears in the cruciate and collateral ligaments (97-100 %); the specificity, however, was lower (50-67 %). The diagnosis of meniscal injury showed low sensitivity (36-56 %) and moderate specificity (69-83 %).

CONCLUSIONS

MRI is a sensitive measure of cruciate and collateral ligament injury in acute knee dislocation; however, it does not reliably diagnose injury to the posterolateral corner or meniscus, and therefore, a higher index of suspicion is required during arthroscopy to prevent misdiagnosis which could affect long-term clinical outcome.

LEVEL OF EVIDENCE

Diagnostic study, Level II.

Relationship Between the Middle Genicular Artery and the Posterior Structures of the Knee: A Cadaveric Study

Background:

The middle genicular artery (MGA) is responsible for the blood supply to the cruciate ligaments and synovial tissue. Traumatic sports injuries and surgical procedures (open and arthroscopic) can cause vascular damage. Little attention has been devoted to establish safe parameters for the MGA.

Purpose:

To investigate the anatomy of the MGA and its relation to the posterior structures of the knees, mainly the posterior capsule and femoral condyles, and to establish safe parameters to avoid harming the MGA.

Study Design:

Descriptive laboratory study.

Methods:

Dissection of the MGA was performed in 16 fresh, unpaired adult human cadaveric knees with no macroscopic degenerative or traumatic changes and no previous surgeries. The specimens were meticulously evaluated with emphasis on preservation of the MGA. The distances from the MGA to the medial and lateral femoral condyles were measured. The Mann-Whitney test was used for statistical analysis.

Results:

In all specimens, the MGA emerged from the anterior aspect of the popliteal artery, distal to the superior genicular arteries, and had a short distal trajectory toward the posterior capsule where it entered proximal to the oblique popliteal ligament. The artery lay in the midportion between the condyles. The distance between the posterior aspect of the tibia and the point of entry of the MGA into the posterior joint capsule was 23.8 ± 7.3 mm (range, 14.72-35.68 mm). There was no correlation between an individual’s height and the distance of the entrance point of the MGA into the posterior joint capsule to the posterior superior corner of the tibia.

Conclusion:

The middle genicular artery lies in the midportion between the medial and lateral femoral condyles.

Clinical Relevance:

This knowledge is important for the preservation of the blood supply during posterior knee surgical procedures and to settle a secure distance between the posterior aspect of the tibia and the MGA input. This could decrease and prevent iatrogenic vascular injury risk to the MGA.

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.

Can Vascular Injury be Appropriately Assessed With Physical Examination After Knee Dislocation?

BACKGROUND

Knee dislocations are rare injuries with potentially devastating vascular complications. An expeditious and accurate diagnosis is necessary, as failing to diagnose vascular injury can result in amputation; however, the best diagnostic approach remains controversial.

QUESTIONS/PURPOSES

We asked: (1) What patient factors are predictors of vascular injury after knee dislocation? (2) What are the diagnostic utilities of palpable dorsalis pedis or posterior tibial pulses, and the presence of an ankle-brachial index (ABI) of 0.9 or greater?

METHODS

A database at a Level I trauma center was queried for patients with evidence of knee dislocation, demographic information (age at the time of injury, sex, Injury Severity Score, BMI, mechanism of injury), and the presence of open injury were recorded. One-hundred forty-one patients underwent screening at initial presentation, of whom 26 (24%) underwent early vascular exploration based on an abnormal physical examination. One-hundred five (91%) of the remaining 115 patients were available at a minimum followup of 6 months (mean, 19 ± 10 months). In total, 31 unique patients were excluded, including 10 patients (7%) who were lost to followup before 6 months. Among the 110 patients who met inclusion criteria, the mean age and SD was 37 ± 13 years, and the Injury Severity Score was 15 ± 9. There were 71 males (65%). Logistic regression was used to determine independent correlates of vascular injury. The vascular examination was reviewed for the presence of a palpable pulse in the dorsalis pedis artery, the presence of a palpable pulse in the posterior tibial artery, and whether the ABI in the dorsalis pedis was 0.9 or greater. Contingency tables were generated to assess the sensitivity, specificity, and accuracy of physical examination maneuvers. The physical examination was collectively regarded as "normal" when both pulses were palpable and the ABI was 0.9 or greater. The initial physical examination as just described was considered the diagnostic test being evaluated in this study; "positive" tests were evaluated by and confirmed at vascular surgery, and 6 months clinical followup without symptoms or progressive signs of vascular injury confirmed the absence of injury in the remainder of the patients. Contingency tables were generated again to assess the sensitivity, specificity, and accuracy of the combined physical examination.

RESULTS

Increased BMI (odds ratio [OR], 1.077; 95% CI, 1.008-1.155; p = 0.033) and open injuries (OR, 3.366; 95% CI, 1.008-11.420; p = 0.048) were associated with vascular injury. No single physical examination maneuver had a 100% sensitivity for ruling out vascular injury. A normal physical examination (palpable pulses and ABI ≥ 0.9) had 100% sensitivity for ruling out vascular injury.

CONCLUSIONS

Increased BMI and the presence of open dislocation are associated with a greater risk for vascular injury after knee dislocation. The combination of a palpable dorsalis pedis and posterior tibial pulse combined with an ABI of 0.9 or greater was 100% sensitive for the detection of vascular injury based on clinical followup at 6 months.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Multiligamentous injuries and knee dislocations

Complex capsular ligamentous structures contribute to stability of the knee joint. Simultaneous injury of two or more knee ligaments, aside from concurrent tears involving the anterior cruciate and medial collateral ligaments, is considered to be associated with femorotibial knee dislocations. Proximal tibiofibular joint dislocations are not always easily recognized and may be overlooked or missed. Patellofemoral dislocations can be transient with MR imaging sometimes required to reach the diagnosis. In this article, the authors describe the mechanism of injury, ligamentous disruptions, imaging, and treatment options of various types of knee dislocations including injuries of the femorotibial, proximal tibiofibular, and patellofemoral joints.

Surgical treatment of multiligament knee injuries

PURPOSE

To analyse one institution's experience with multiligament knee injuries.

METHODS

Over 10 years, 133 multiligament knee injuries including 130 patients were included in the study. Inclusion criteria included: (1) injury to two or more knee ligaments (2) multiligament knee repair/reconstructive surgery.

RESULTS

The average age at time of injury was 26 years old, and 76 % were male. Fifty-one (38 %) multiligament knee injuries had >2 ligaments injured. Peroneal injuries occurred in 26 patients (20 %), and four (3 %) had associated vascular injuries. A high energy mechanism of injury was noted in 39 %. Twenty-five per cent of patients had an additional orthopaedic injury and, 11.5 % suffered additional non-orthopaedic injuries. Definitive surgical intervention was performed acutely (<3 weeks) in 47 %. Ninety-one per cent of multiligament knee injuries underwent reconstruction with or without repair. Forty-three complications occurred in 37 patients. Patients who suffered >2 ligament injury or had surgery acutely were at an increased risk of knee stiffness requiring manipulation under anaesthesia (MUA) (p = 0.016 and p = 0.047, respectively). Knees with >2 ligaments injured were associated with higher post-operative complications (p = 0.007). Knee dislocation IV knees were at increased risk to undergo revision surgery (p = 0.041). Obese patients were more likely to have a post-operative infection (p = 0.038). Repair, reconstruction or type of graft used had no impact on need for revision surgery.

CONCLUSIONS

Multiligament knee injured patients undergoing surgical intervention are a highly complex patient population. This study outlines the patient population, treatment, and complications of one academic institution over 10 years. Overall complications were higher in patients with >2 ligaments injured. Knee stiffness requiring MUA was more common in patients who had >2 ligaments ruptured and those treated acutely. Knees with all four ligaments injured were more likely to undergo revision surgery.

LEVEL OF EVIDENCE

Retrospective case series, Level IV.

Simultaneous bilateral multiligamentous knee injuries are associated with more severe multisystem trauma compared to unilateral injuries

PURPOSE

To compare the knee ligamentous injury patterns and associated multisystem trauma in patients who have sustained simultaneous bilateral knee multiligamentous injuries (MLI) to patients with unilateral MLIs.

METHODS

Patients with simultaneous bilateral and unilateral knee MLIs after motor vehicle accidents were identified from 2007 to 2014 at a single institution. Chart and radiographic reviews were performed to identify patient demographics, extremity fractures and associated head, thoracic, abdominal and spine injuries. The MLIs were characterized by ligamentous injury pattern and associated neurovascular deficits. Injury Severity Score (ISS) and New ISS (NISS) were calculated.

RESULTS

Seven bilateral MLIs and 32 unilateral MLIs were identified. Between the cohorts, there were no significant differences in ligamentous injury pattern or associated neurovascular injuries. For the bilateral MLI cohorts, 71.4 % of patients sustained chest trauma, 57.1 % abdominal trauma, 57.1 % at least a single-level spine injury and 28.6 % head trauma. The ISS was 33.4 ± 23.4 with patients spending an average of 12.4 days in the intensive care unit. Other than the number of days in the ICU, these values were all significantly higher than those of the unilateral knee MLI cohort. Additionally, there was a significantly higher post-operative complication rate in the bilateral MLI cohort (71.4 vs. 6.3 %, P < 0.0001).

CONCLUSION

Compared to unilateral MLIs with similar mechanisms, patients with traumatic simultaneous bilateral knee multiligamentous knee injuries are at high risk of concomitant head, chest and abdominal injuries. Although the ligament injury profile is similar, the post-operative complication rate is higher for simultaneous bilateral injuries.

LEVEL OF EVIDENCE

Case control study, Level III.

Physical examination and imaging of the lateral collateral ligament and posterolateral corner of the knee

The initial assessment of injury to the lateral collateral ligament and posterolateral corner is often challenging, particularly in the context of a multiligamentous injury. Although advanced imaging techniques have enhanced the evaluation of knee injuries, the significant, and often unique, contribution of clinical examination should not be overlooked. Clinical examination starts with a thorough history, which is instrumental in elucidating not only the patient's symptomatology but also the mechanism of injury. Differentiating between acute and chronic injury and teasing out the patient's functional limitations are instructive in defining the appropriate treatment plan. The treating physician needs patience, vigilance, and a variety of diagnostic tools to reach a precise diagnosis. Each injury should be approached in a methodical and systematic manner to ensure an accurate initial assessment. This review provides a step-wise approach to the clinical assessment of the lateral collateral ligament and posterolateral corner injured knee. Adjunctive imaging modalities and investigations are also discussed.

Management of the Floating Knee in Polytrauma Patients

Ipsilateral fracture of the femur and tibia, or floating knee, is a rare injury that is found almost exclusively in polytrauma or high-energy trauma patients. It presents a combination of diaphyseal, metaphyseal and intra-articular fractures of the femur and tibia, with a high incidence of neurovascular, ligamentous and soft-tissue injuries. The functional outcome and, in some cases, the life, of such polytrauma patients depends largely on a correct therapeutic approach being taken. In general, the treatment decided upon will depend on the individual characteristics present, regarding aspects such as the patient’s general condition, the fracture line and the state of the soft tissues. The treatment provided may be the same as when single fractures are presented, but it is often necessary to consider whether certain techniques or surgical approaches may interfere with other lines of treatment. It is essential at all times to take into consideration the associated injuries and complications before deciding upon a treatment strategy. Ligamentous injuries play an important role in these injuries, much more so than when fractures occur singly. Therefore, these injuries require management by an experienced multidisciplinary team.