Initial Evaluation and Classification of Knee Dislocations

Lateral Meniscal Root Displacement into the Popliteal Hiatus in a Multiligamentous Knee Injury: A Case Report

CASE

A 45-year-old female patient presented with left knee pain after a ski accident. Magnetic Resonance Imaging (MRI) showed complete rupture of the anterior cruciate ligament, posterior cruciate ligament, proximal Medial Collateral Ligament (MCL), and medial patellofemoral ligament. The lateral meniscal root was torn with the posterior horn incarcerated superiorly into the popliteal hiatus, rendering high risk of plastic deformation. An unconventional 2-staged surgical approach was performed.

CONCLUSION

Where risk of meniscal plastic deformation is high in the setting of multiligamentous knee injury (MLKI), diagnosis and careful surgical planning are central to a successful outcome. Treatment of intra-articular structures in operative stage 1 in MLKI is possible and was necessary in this case.

Examining the Schenck KD I Classification in Patients With Documented Tibiofemoral Knee Dislocations: A Multicenter Retrospective Case Series

Background

Acute tibiofemoral knee dislocations (KDs) with a single cruciate ligament remaining intact are rare and can be classified as Schenck KD I. The inclusion of multiligament knee injuries (MLKIs) has contributed to a recent surge in Schenck KD I prevalence and has convoluted the original definition of the classification.

Purpose

To (1) report on a series of true Schenck KD I injuries with radiologically confirmed tibiofemoral dislocation and (2) introduce suffix modifications to further subclassify these injuries based on the reported cases.

Study Design

Case series; Level of evidence, 4.

Methods

A retrospective chart review identified all Schenck KD I MLKIs at 2 separate institutions between January 2001 and June 2022. Single-cruciate tears were included if a concomitant complete disruption of a collateral injury was present or injuries to the posterolateral corner, posteromedial corner, or extensor mechanism. All knee radiographs and magnetic resonance imaging scans were retrospectively reviewed by 2 board-certified orthopaedic sports medicine fellowship-trained surgeons. Only documented cases consistent with a complete tibiofemoral dislocation were included.

Results

Of the 227 MLKIs, 63 (27.8%) were classified as KD I, and 12 (19.0%) of the 63 KD I injuries had a radiologically confirmed tibiofemoral dislocation. These 12 injuries were subclassified based on the following proposed suffix modifications: KD I-DA (anterior cruciate ligament [ACL] only; n = 3), KD I-DAM (ACL + medial collateral ligament [MCL]; n = 3), KD I-DPM (posterior cruciate ligament [PCL] + MCL; n = 2), KD I-DAL (ACL + lateral collateral ligament [LCL]; n = 1), and KD I-DPL (PCL + LCL; n = 3).

Conclusion

The Schenck classification system should only be used to describe dislocations with bicruciate injuries or with single-cruciate injuries that have clinical and/or radiological evidence of tibiofemoral dislocation. Based on the presented cases, the authors recommend the suffix modifications for subclassifying Schenck KD I injuries with the goal of improving communication, surgical management, and the design of future outcome studies.

Team Approach: Treatment of Traumatic Dislocations of the Knee

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Traumatic knee dislocations are complex injuries that can be associated with compromise of the neurovascular structures about the knee.

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Various classification systems for knee dislocations exist in the literature but should be used with caution as a prognostic tool because many knee dislocations fit into more than 1 category.

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Special populations of knee dislocations, such as obese patients and high-velocity mechanism injuries, require additional caution during the initial evaluation for possible vascular injuries.

MUSCLE INJURY AND SPORTS REHABILITATION MANAGEMENT IN ENDURANCE TRAINING ORIENTED TO WINTER SPORTS

ABSTRACT Introduction: Muscle injury in ski sports training has gradually increased, greatly impairing performance in ice and snow sports competitions. Objective: To study muscle injury and muscle movement during ice and snow sports training and the rehabilitation of muscle injuries. Methods: Thirty skiers with knee muscle injuries were selected as subjects and underwent rehabilitation training for six weeks, and the indicators were statistically evaluated. Results: The ski injuries were mainly muscle strain, muscle or ligament strain, and ligament rupture. The indices after treatment were significantly different from those before treatment (P < 0.05); compared with the three rehabilitation programs, the improvement of each index in group C was significantly different from that in the other two groups (P < 0.05), while there was no significant difference in the improvement of each index between the multi-angle isometric training treatment in group A and the proprioceptive neuromuscular stimulation technique in group B (P>0.05). Conclusion: The influence of recovery training technology on knee muscle re-education was proposed, and a rehabilitation plan for skiing was presented. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

No Difference in Knee Kinematics Between Anterior Cruciate Ligament-First and Posterior Cruciate Ligament-First Fixation During Single-Stage Multiligament Knee Reconstruction: A Biomechanical Study

Background:

For combined reconstruction of both the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL), there is no consensus regarding which graft should be tensioned and fixed first.

Purpose:

The purpose of this study was to determine which sequence of graft tensioning and fixation better restores normal knee kinematics. The hypothesis was that ACL-first fixation would more closely restore normal knee kinematics, graft force, and the tibiofemoral orientation in the neutral (resting) position compared with PCL-first fixation.

Study Design:

Controlled laboratory study.

Methods:

A total of 15 unpaired human cadaveric knees were examined using a robotic testing system under the following 4 conditions: (1) 89.0-N anterior tibial load at different knee angles; (2) 89.0-N posterior tibial load at different knee angles; (3) combined rotational 7.0-N·m valgus and 5.0-N·m internal rotation load (simulated pivot shift) at 0°, 15°, and 30° of flexion; and (4) 5.0-N·m external rotation load at 0°, 15°, and 30° of flexion. The 4 evaluated knee states were (1) intact ACL and PCL (intact), (2) ACL and PCL deficient (deficient), (3) combined anatomic ACL-PCL reconstruction fixing the ACL first (ACL-first), and (4) combined anatomic ACL-PCL reconstruction fixing the PCL first (PCL-first). A 9.0 mm–diameter quadriceps tendon autograft was used for the ACL graft, tensioned with 40.0 N at 30° of flexion. A 9.5 mm–diameter hamstring tendon autograft (gracilis and semitendinosus, quadrupled loop, and augmented with an additional allograft strand if needed), tensioned with 40.0 N at 90° of flexion, was used for the PCL graft.

Results:

There were no statistically significant differences between ACL-first and PCL-first fixation regarding knee kinematics. ACL-first fixation restored anterior tibial translation to the intact state at all tested knee angles, while PCL-first fixation showed higher anterior tibial translation than the intact state at 90° of flexion (9.05 ± 3.05 and 5.87 ± 2.40 mm, respectively; P = .018). Neither sequence restored posterior tibial translation to the intact state at 30°, 60°, and 90° of flexion. At 15° of flexion, PCL-first fixation restored posterior tibial translation to the intact state, whereas ACL-first fixation did not.

Conclusion:

There were no differences in knee laxity between ACL-first and PCL-first fixation with the ACL graft fixed at 30° and the PCL graft fixed at 90°.

Clinical Relevance:

This study showed that there was no evidence to support the use of one tensioning sequence over the other in single-stage multiligament knee reconstruction.

An Evidence-Based Approach to Multi-Ligamentous Knee Injuries

Multi ligament knee injuries (MLKIs) are highly complex injuries with associated complications and often present with difficult management strategies. MLKIs may affect the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (or posteromedial corner (PMC)), and lateral collateral ligament (or posterolateral corner (PLC)) in addition to other structures including the menisci, common peroneal nerve, and popliteal artery. MLKIs are highly associated with the male sex and are commonly seen in high-velocity motor vehicle accidents and low-velocity sports injuries. Given the multiple planes of movement in the knee and various primary and secondary stabilizers throughout those planes, there is great heterogeneity in an injury pattern and most involve the ACL and PCL. Initial evaluation of this injury includes assessment of lower extremity sensation, distal pulses, and ankle-brachial index (ABI). If vascular compromise is suspected, computed tomography angiography (CTA) or magnetic resonance angiography (MRA) are indicated to evaluate the vasculature. As opposed to CTA, MRA offers visualization of the soft-tissue structures that are commonly damaged in MLKIs. Initial management typically includes closed reduction of the knee with subsequent external fixation. Classification systems guide initial assessments; however, further management is unclear and leads the surgical team to decide the best, individualized management option for each patient. As a result, optimal surgical and postoperative treatment options remain complicated, and clinical outcomes remain difficult to predict. The purpose of this review is to consolidate the most up-to-date practices of the diagnostic workup, management, and treatment of MLKIs.

Acute Femoropopliteal Bypass Graft Occlusion After Knee Manipulation Under Anesthesia: A Case Report and Review of Current Literature

Bilateral tibiofemoral knee dislocations are a relatively rare injury, and there is a scarcity of literature on its appropriate evaluation and treatment. Even less knee dislocations with concomitant popliteal artery injury have been described. Postoperative graft occlusion accounts for approximately half of the overall complication rate, occurring in up to 18% of the patients undergoing femoropopliteal bypass grafting. Furthermore, anticoagulation and antiplatelet therapy after graft placement is a point of contention. Here, we describe a case of a knee dislocation with associated popliteal artery transection treated initially with successful knee-spanning external fixation and arterial grafting, respectively. At 6 weeks after injury, the patient underwent external fixation removal and closed manipulation of the knee for arthrofibrosis. After manipulation, yet still under anesthesia, distal pulses were acutely diminished and subsequent CTA demonstrated femoropopliteal graft thrombosis. This case demonstrates successful recognition, thrombectomy, and restoration of arterial blood flow, which has since been maintained. Written consent by the patient involved in this case report was obtained.

[Application of high tibial osteotomy for chronic multi-ligament knee injury associated with lower extremity malalignment]

OBJECTIVE

To investigate the feasibility and effectiveness of high tibial osteotomy (HTO) in treatment of chronic multi-ligament knee injury (MLKI) associated with lower extremity malalignment.

METHODS

A clinical data of 14 patients (14 knees) of chronic MLKI associated with lower extremity malalignment, who were treated with HTO between January 2016 and September 2020, was retrospectively analyzed. There were 10 males and 4 females, with an average age of 30.5 years (range, 22-48 years). The causes of injury included traffic accident in 8 cases, bruising by a heavy object in 3 cases, falling from height in 2 cases, and twisting in 1 case. According to Schenck classification of knee dislocation (KD), there were 4 cases of KD-Ⅰ [2 cases of anterior cruciate ligament (ACL) and posterolateral complex (PLC) injuries and 2 cases of posterior cruciate ligament (PCL) and PLC injuries], 7 cases of KD-Ⅲ (all of ACL, PCL, and PLC injuries), and 3 cases of KD-Ⅳ. The preoperative hip-knee-ankle angle (HKA) was (167.1±4.7)°, and the posterior tibial slope angle (PTSA) was (16.3±2.7)°. The knee joint was severely unstable and the patients could not stand and walk normally. Among them, 5 cases of medial compartment cartilage were severely worn out (3 cases of Kellgren-Lawrence grading Ⅱ, 2 cases of grading Ⅲ) causing pain. After admission, 2 cases of KD-Ⅰ underwent HTO and ligament reconstruction in the first stage, 1 case of KD-Ⅲ and 1 case of KD-Ⅳ underwent HTO in the first stage and ligament reconstruction in the second stage; the remaining 10 patients only underwent HTO.

RESULTS

All patients were followed up 12-50 months, with an average of 30 months. The incisions healed by first intention after operation, and no complications such as infection and deep vein thrombosis of the lower extremities occurred. At 12 months after operation, knee range of extension was -5°-0° (mean, -1.2°) and range of flexion was 110°-140° (mean, 125.5°). The Lachman test was negative in 11 cases and positive in 3 cases. The posterior drawer test was negative in 9 cases and positive in 5 cases. The 0/30° varus stress test was negative in 10 cases and positive in 4 cases. The 0/30° valgus stress test was negative in 13 cases and positive in 1 case. The visual analogue scale (VAS) score was significantly lower than that before operation ( P<0.05), and the International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score were all significantly higher than those before operation ( P<0.05). The X-ray film reexamination at 12 months after operation showed that the HKA was (178.2±3.8)° and the PTSA was (8.6±2.4)°, which were significantly different from those before operation ( P<0.05). All osteotomies achieved bone union, and the healing time was 3-11 months, with an average of 6.8 months.

CONCLUSION

For chronic MLKI associated with lower extremity malalignment, HTO can restore normal lower extremity alignment and improve knee joint function, which is a feasible salvage operation.

Single-Stage Arthroscopy-Assisted Reduction and Internal Fixation (ARIF) of Tibial Rim Fracture With Posterior Cruciate Ligament Reconstruction and Repair of Posterolateral Complex and Meniscal Injury

Multiligament knee injury with periarticular fractures are high-velocity injuries and generally require a staged treatment approach that involves multiple hospitalizations and results in delayed return to activity. We report a single-stage management technique for these injuries with arthroscopy-assisted reduction and internal fixation of a depressed tibial rim fracture with concomitant posterolateral complex repair, medial meniscal repair, and posterior cruciate ligament reconstruction.

RESEARCH ON KNEE SPORTS INJURY CLASSIFICATION BASED ON MEDICAL IMAGES AND KWON3D SOFTWARE

ABSTRACT Introduction: The integrity of articular cartilage determines the functional state of the joint. In recent years, the development of MRI sequences of various articular cartilage has become the focus of many research topics. Objective: The accuracy of diagnosis of knee cartilage injury caused by motion injury was studied retrospectively by meta-three-dimensional software. Methods: Forty-six knee joints of 45 patients with sports injuries, multi-sequence MRI was performed before surgery, including conventional knee MRI (SET1WI, FSEPD/T2WI), 3D SPGR, and 3D FIESTA sequences. Results: According to the operation results, the sensitivity, specificity, positive predictive value, and negative predictive value of 3D SPGR combined with conventional MRI sequence evaluation of cartilage damage are the highest, 73%, 98%, 95%, and 90%. Conclusions: 3D SPGR combined with conventional MRI sequences can improve accurate evaluation and diagnosis of cartilage disease over a reasonable scan time. Level of evidence II; Therapeutic studies - investigation of treatment results.

Schenck's knee dislocation (KD) I injury: An uncommon pattern

Schenck's knee dislocation (KD) I is a very uncommon pattern of KD, where the knee presents with clinical or radiographic evidence of a KD with one of the ligaments of the central pivot preserved. The correlation between imaging and physical examination is of the highest importance to correctly classify this injury. Recently, there have been reports in the literature with large numbers of Schenk's KD I, however this is due to classifying multiligament knee injuries as if they all were KDs rather to an increase of the pattern. In this report the case of an 18-year old patient that sustained a KD with a preserved posterior cruciate ligament is presented.