Treatment of Combined Injuries to the ACL and the MCL Complex: A Consensus Statement of the Ligament Injury Committee of the German Knee Society (DKG)

A structured framework for standardized 3D leg alignment analysis: an international Delphi consensus study

PURPOSE

To reach consensus among international experts on a structured framework for standardized 3D leg alignment analysis based on 3D bone models, ensuring consistency and improving clinical applicability.

METHODS

A Delphi study was performed in four rounds. Rounds 1 and 2 involved a steering and rating group that developed statements based on principles preserving the 3D complexity of anatomical structures, identified through a systematic review. These statements encompassed approaches for deriving joint centres and joint orientations, and defining coordinate systems using 3D bone models. In Rounds 3 and 4, a panel of 35 international experts, including clinicians (54%) and engineers (46%), with participants from Europe (80%), Oceania (9%), Asia (6%), and the Americas (6%), evaluated these statements. Consensus was defined as ≥80% agreement.

RESULTS

Rounds 1 and 2 resulted in 31 statements to be included in the survey. Of these, 26 achieved consensus in Round 3, with the five remaining statements refined and reaching consensus in Round 4. Experts agreed on utilising all available relevant surface data to define joint centres, joint orientations, and individual femoral and tibial coordinate systems alongside a combined leg coordinate system, and adopting central 3D axes for femoral version and tibial torsion.

CONCLUSIONS

This international Delphi consensus study provides a structured framework for a standardized 3D leg alignment analysis based on 3D bone models. This framework aims to enhance clinical applicability for preoperative planning and execution of uni- and multiplanar correction osteotomies around the knee, reduce the methodological variability in 3D leg alignment analysis literature, and improve cross-study comparability.

LEVEL OF EVIDENCE

Level V.

Evaluation of the Stability, Revision Rate, and Complication Profile of Combined Anterior Cruciate Ligament Reconstruction with Lateral Extra-Articular Tenodesis and Hughston Procedure in Anterior Cruciate Ligament and Medial Collateral Ligament Injury: An 8-Year Cohort Study

Background

Anterior cruciate ligament (ACL) tears combined with medial collateral ligament (MCL) injury has been associated with an increased rate of ACL reconstruction (ACLR) failure, high-grade pivot shift (PS), and lower return to sports rate. On the other hand, medial-sided procedures in the setting of ACLR are associated with knee stiffness and arthrofibrosis.

Purpose/Hypothesis

This study aimed to compare clinical scores, objective knee laxity, failure, and complication rates in 2 different patient groups. The combination of ACL reconstruction with LET and the Hughston procedure yields comparable failure rates, complication rates, and clinical outcomes to ACL reconstruction with LET in patients without medial instability.

Study Design

Cohort study; Level of evidence, 3.

Methods

A group of patients had a combined ACL and MCL injury grade 2 with chronic instability and underwent ACLR associated with lateral extra-articular tenodesis (LET) and the Hughston procedure (Hughston group). The control group included matched patients with isolated ACL lesion without medial instability who underwent ACL reconstruction with LET (control group). Patient-reported outcome measures, complications, and reoperations were collected for both groups. A clinical evaluation was performed including objective anteroposterior laxity measurement (KT-1000 arthrometer) and PS quantification. The primary outcomes were ACL revision and ACL-clinical failure, a composite parameter of anteroposterior and rotatory laxity. A test for 2-way analysis of variance for repeated measures was performed to assess the between-group differences (P < .05). Surgical and clinical failure were assessed via Kaplan-Meier method.

Results

A total of 70 patients (35 per group) were enrolled in the present study at a follow-up of 8.1 ± 2.7 years. All the patient-reported outcome measures significantly improved at the final follow-up with no difference between the 2 groups (P > .05). ACL revision was performed in 2 of 35 (5.7%) patients in both groups (P = .79). A total of 10 patients (4 in the Hughston group and 6 in the control group) were excluded from the analysis of the clinical failures due to contralateral-side injury. Clinical failure was identified in 7 of 28 (25.0%) patients in the Hughston group and 5 of 29 (17.2%) in the control group (P = .59). Reoperation due to knee stiffness was required only in 1 of 35 patients (2.9%) of the Hughston group.

Conclusion

Due to its simplicity and cost-effectiveness, the Hughston technique should be included in the orthopaedic surgeon's armamentarium for the treatment of moderate anteromedial instability in combined ACL and MCL injury. Moreover, the outcomes and failure rate of the Hughston technique combined with an ACLR + LET are similar to that of an ACLR + LET used to treat an isolated ACL injury.

Functional knee bracing provides protection to the anterior cruciate ligament in response to rotatory loads

BACKGROUND

The aim of the study was to quantify the effect of functional knee bracing on native knee kinematics and the in-situ force in the ACL in response to external loading.

METHODS

A robotic testing system was used to apply three external loads from full extension to 60° of flexion to eight fresh frozen human cadaveric knees: 1) a 134 N anterior load, 2) a combined 5-Nm internal rotation +5-Nm valgus torque, and 3) a combined 5-Nm external rotation +5-Nm valgus torque. For native and braced states, kinematics were recorded and the in-situ force in the ACL was determined.

FINDINGS

In response to the combined internal + valgus torque, ideal bracing significantly reduced internal rotation at each flexion angle and valgus rotation at 60° of flexion and reduced the in-situ force in the ACL at full extension and 30° of flexion. In response to the combined external + valgus torque, ideal bracing significantly reduced external rotation at each flexion angle and the in-situ force in the ACL at full extension. Ideal bracing had no effect on kinematics in the other degrees of freedom or on the in-situ force in the ACL in response to a 134 N anterior load.

INTERPRETATION

Ideal knee bracing provided a protective effect on the ACL in response to a combined 5-Nm internal rotation +5-Nm valgus torque but had minimal impact in response to anterior loading and valgus torque. Therefore, ideal functional knee bracing may improve rotatory stability and provide protection to the ACL.

The use of four K-wires does not lead to a reduction of the MPTA in the context of a one-dimensional tibial deflection correction of patients with ACL re-rupture and pathologically increased tibial slope

Purpose

Anterior tibial closing wedge osteotomy (ATCWO) has been shown to significantly reduce failure rates of revision anterior cruciate ligament (ACL) reconstructions in patients with a posterior tibial slope (PTS) ≥12°. Recent findings suggest a slight but significant reduction of the medial proximal tibial angle (MPTA) resulting in a varus knee where the sagittal osteotomy plane is based on a total of two guide wires defining the osteotomy wedge without respecting the frontal plane. We hypothesize that the placement of a total of four guide wires intraoperatively can reduce the influence on the MPTA.

Methods

This study retrospectively reports on a two-centre series of 42 ATCWOs for PTS correction between January 2022 and December 2023 at two clinical centres. A total of four guide wires were placed based on a true lateral intraoperative view of the tibia, with two positioned each at the cranial and at the caudal pole of the osteotomy wedge, serving as guides for the saw to create the osteotomy, with careful attention to ensuring that the proximal and distal K-Wires were placed parallel to each other. A retrospective analysis was conducted by examining true lateral and anteroposterior radiographs to identify changes in sagittal and coronal plane alignment.

Results

The study included 19 women and 23 men, with a mean age of 29.7 ± 8.6 years with first-time ACL revision surgery and a minimum PTS of ≥12°. PTS decreased significantly from 14.5 ± 2.8° preoperatively to 8.2 ± 1.9° post-operatively (p < 0.001). The aMPTA demonstrated no significant difference between preoperative (mean aMPTA: 86.9 ± 2.1°) and post-operative (mean aMPTA: 86.6 ± 1.9°) measurements (p > 0.05).

Conclusion

With our technique of placing four guide wires to achieve precise guidance during the insertion of the osteotomy wedge, there is no substantial impact on the aMPTA during slope correction.

Level of Evidence

Level IV.

Collateral ligament strain is linearly related to coronal lower limb alignment: A biomechanical study

PURPOSE

The purpose of this study was to analyse the influence of coronal lower limb alignment on collateral ligament strain.

METHODS

Twelve fresh-frozen human cadaveric knees were used. Long-leg standing radiographs were obtained to assess lower limb alignment. Specimens were axially loaded in a custom-made kinematics rig with 200 and 400 N, and dynamic varus/valgus angulation was simulated in 0°, 30°, and 60° of knee flexion. The changes in varus/valgus angulation and strain within different fibre regions of the collateral ligaments were captured using a three-dimensional optical measuring system to examine the axis-dependent strain behaviour of the superficial medial collateral ligament (sMCL) and lateral collateral ligament (LCL) at intervals of 2°.

RESULTS

The LCL and sMCL were exposed to the highest strain values at full extension (p < 0.001). Regardless of flexion angle and extent of axial loading, the ligament strain showed a strong and linear association with varus (all Pearson's r ≥ 0.98; p < 0.001) and valgus angulation (all Pearson's r ≥ -0.97; p < 0.01). At full extension and 400 N of axial loading, the anterior and posterior LCL fibres exceeded 4% ligament strain at 3.9° and 4.0° of varus, while the sMCL showed corresponding strain values of more than 4% at a valgus angle of 6.8°, 5.4° and 4.9° for its anterior, middle and posterior fibres, respectively.

CONCLUSION

The strain within the native LCL and sMCL was linearly related to coronal lower limb alignment. Strain levels associated with potential ultrastructural damages to the ligaments of more than 4% were observed at 4° of varus and about 5° of valgus malalignment, respectively. When reconstructing the collateral ligaments, an additional realigning osteotomy should be considered in cases of chronic instability with a coronal malalignment exceeding 4°-5° to protect the graft and potentially reduce failures.

LEVEL OF EVIDENCE

There is no level of evidence as this study was an experimental laboratory study.

Current trends in the medial side of the knee: not only medial collateral ligament (MCL)

The medial collateral ligament (MCL) is by far the most commonly injured ligament of the knee. The medial ligament complex covers a broad bony surface on the extraarticular portion of the femur and is highly vascularized, which allows for a high healing potential. For this reason, most MCL complex lesions were treated conservatively in the past. However, recent advancements regarding the MCL anatomy and kinematics highlighted the complex biomechanical behavior of the isolated and combined MCL lesion, and it is now fully appreciated that some MCL lesions warrant surgical treatment. The present review aims to provide the reader with an overview of the new evidence and advancement on the complex anatomy, biomechanics, and treatment of the MCL.

[Reconstruction of the medial collateral ligament complex with a flat semitendinosus auto- or allograft]

OBJECTIVE

Replacement of superficial medial collateral ligament (sMCL) and posterior oblique ligament (POL) with an allograft.

INDICATIONS

Chronic 3° isolated medial instability and combined anteromedial or posteromedial instability.

CONTRAINDICATIONS

Infection, open growth plates, restricted range of motion (less than E/F 0-0-90°).

SURGICAL TECHNIQUE

Longitudinal incision from medial epicondyle to superficial pes anserinus and exposure of the medial collateral ligament complex. Thawing of the allogeneic semitendinosus tendon graft at room temperature, reinforcement of the tendon ends with sutures and preparation of a two-stranded graft. Placement of guidewires in the sMCL and POL insertions and control with image intensifier. Tunnel drilling. Pulling the graft loop into the femoral bone tunnel and fixation with a flip button. Pulling the two graft ends into the tibial tunnels. Tibial fixation by knotting the suture ends in a 20° flexion on the lateral cortex. Suture the tendon bundles to the remaining remnants of the medial collateral ligament complex to adopt the flat structure of the natural medial collateral ligament complex.

POSTOPERATIVE MANAGEMENT

Six weeks partial weight-bearing, immediately postoperatively splint in the extended position, after 2 weeks movable knee brace for another 4-6 weeks. Mobility: 4 weeks 0-0-60, 5th and 6th weeks 0-0-90.

RESULTS

From 2015-2021, this surgical procedure was performed in 19 patients (5 women, 14 men, age 34 years). Mean Lysholm score at follow-up after at least 2 years was 89 (76-99) points. In 6 patients, there was restricted range of motion 3 months postoperatively, which resulted in further therapy (3 × systemic cortisone therapy, 3 × arthroscopically supported manipulations under anesthesia).

Follow-up Treatment after Cartilage Therapy of the Knee Joint - a Recommendation of the DGOU Clinical Tissue Regeneration Working Group

The first follow-up treatment recommendation from the DGOU's Clinical Tissue Regeneration working group dates back to 2012. New scientific evidence and changed framework conditions made it necessary to update the follow-up treatment recommendations after cartilage therapy.As part of a multi-stage member survey, a consensus was reached which, together with the scientific evidence, provides the basis for the present follow-up treatment recommendation.The decisive criterion for follow-up treatment is still the defect localisation. A distinction is made between femorotibial and patellofemoral defects. In addition, further criteria regarding cartilage defects are now also taken into account (stable cartilage edge, location outside the main stress zone) and the different methods of cartilage therapy (e. g. osteochondral transplantation, minced cartilage) are discussed.The present updated recommendation includes different aspects of follow-up treatment, starting with early perioperative management through to sports clearance and resumption of contact sports after cartilage therapy has taken place.

Knotless Suture Anchors Display Favorable Elongation but an Inferior Ultimate Failure Load Versus Titanium Suture Anchors and All-Suture Anchors: A Biomechanical Comparison in a Porcine Model

Background

Several types of suture anchors, which differ in their working principles, are available for fixation of ligamentous structures in knee surgery. How the choice of a suture anchor type influences the biomechanical stability of ligament fixation is largely unknown.

Purpose

To compare the biomechanical properties of different suture anchor designs regarding primary stability for tendon fixation and repair in medial collateral ligament (MCL) surgery.

Study Design

Controlled laboratory study.

Methods

The primary stability of MCL fixation was assessed in a porcine model utilizing 1 of 3 suture anchor types: a 5.5-mm titanium suture anchor (TSA), a 2.8-mm all-suture anchor (ASA), or a 5.5-mm polyether ether ketone knotless suture anchor (KLSA). Primary stability was assessed using a uniaxial material testing machine. Cyclic loading at 50 N and 100 N was applied for 500 cycles each, followed by a load-to-failure test.

Results

After 500 cycles at 50 N, the KLSA (2.4 ± 0.3 mm) showed significantly (P < .05) reduced elongation in comparison to the TSA (4.0 ± 0.9 mm) and ASA (3.6 ± 0.7 mm), and after 500 cycles at 100 N, the KLSA (6.5 ± 1.4 mm) again showed significantly (P < .05) reduced elongation in comparison to the TSA (11.0 ± 2.2 mm) and ASA (12.0 ± 3.6 mm). However, the KLSA (213 ± 27 N) showed a significantly (P < .05) inferior ultimate failure load in comparison to the TSA (300 ± 20 N) and ASA (348 ± 23 N). In comparison to the TSA (113.0 ± 11.0 N/mm) and ASA (113.6 ± 14.4 N/mm), the KLSA (150.7 ± 11.6 N/mm) displayed the highest stiffness (P < .05). No significant differences were observed regarding yield load.

Conclusion

KLSAs displayed significantly reduced elongation, at the cost of a reduced ultimate failure load, in comparison to TSAs and ASAs.

Clinical Relevance

Surgeons should be aware that differences exist between different suture anchor types regarding their biomechanical stability. KLSAs may be favorable for fixation of peripheral ligaments in knee surgery.

Diagnostic Musculoskeletal Ultrasound for Medial Collateral Ligament Injuries: Applications in Rehabilitation

Medial collateral ligament (MCL) injuries are prevalent in sports and other physical activities and constitute a significant cause of knee pain and dysfunction. Traditional diagnostic modalities such as magnetic resonance imaging (MRI) are often utilized for their detailed visualization capabilities. However, musculoskeletal ultrasound (MSK-US) has emerged as a pivotal diagnostic tool in the evaluation of MCL injuries due to its non-invasive nature, cost-effectiveness, and dynamic imaging capabilities. This article reviews the utility and advantages of MSK-US in diagnosing MCL injuries, with a specific focus on its implications for rehabilitation providers. We discuss the technical aspects of ultrasound (US) imaging, including the sonographic appearance of MCL injuries across various grades, and compare its diagnostic accuracy with other imaging modalities such as MRI. Additionally, the role of US in monitoring the healing process and guiding rehabilitation strategies is explored. This review emphasizes the practical application of MSK-US in clinical settings, offering rehabilitation providers a comprehensive understanding of how US can be integrated into patient management protocols to enhance outcomes in patients with MCL injuries.

Predicting the Recovery of Isokinetic Knee Strength 6 Months After Anterior Cruciate Ligament Reconstruction

Background

The limb symmetry index (LSI) is a metric of strength restoration. It is key to successfully return to sports after anterior cruciate ligament (ACL) reconstruction. The threshold for return to sports is generally considered an LSI of ≥85%.

Purpose

To develop a statistical model for predicting the recovery of knee extension and flexion strength (with LSI ≥85%) at 6 months after ACL reconstruction.

Study Design

Case-control study; Level of evidence: 3.

Methods

Patients who underwent arthroscopic ACL reconstruction between November 2015 and December 2020 were included. The patients were classified into 2 groups: "pass" if the LSI at 6 months postoperatively was ≥85% and "fail" if the LSI was <85%. Factors in 25 categories with 74 levels, including patient characteristics, periarticular procedures, intra-articular lesions and treatment, and perioperative management, were collected. A multivariable logistic regression combined with backward variable elimination was used to determine the predictive parameters for recovery of knee extension and flexion strength.

Results

A total of 948 patients were included. Graft site, preoperative isokinetic strength, treatment of meniscal injury, and injured side (left vs right) were identified as general predictors for both knee extension and flexion strength. For knee extension strength, age at injury and partial weightbearing duration were identified as additional predictors. For knee flexion strength, type of meniscal injury, surgeon volume, cartilage procedures, and periarticular procedures were identified as additional predictors. The Nagelkerke R 2 of the final model was 0.178, and the c-statistic was 0.716 (95% CI, 0.676-0.754). The Hosmer-Lemeshow test indicated good calibration (P = .879).

Conclusion

Several factors including preoperative isokinetic strength, treatment of meniscal injuries, left vs. right side and graft site were found to predict recovery of ≥85% LSI in knee extension and flexion strength. Despite the numerous factors that were analyzed, the predictive power was moderate (c-statistic = 0.716), indicating there were other nonincluded factors that significantly influence strength performance at 6 months postoperatively.

Secondary restraints in ACL reconstruction: State-of-the-art

At-risk patients continue to experience a high likelihood of graft rupture after anterior cruciate ligament (ACL) reconstruction (ACLR). This narrative review seeks to provide the reader with an evidence-based synopsis of state-of-the-art concepts related to secondary restraint lesions, and how addressing them surgically might result in improved outcomes of ACLR.

Career Length After Surgically Treated ACL Plus Collateral Ligament Injury in Elite Athletes

BACKGROUND

Limited data are available regarding career length and competition level after combined anterior cruciate ligament (ACL) and medial- or lateral-sided surgeries in elite athletes.

PURPOSE

To evaluate career length after surgical treatment of combined ACL plus medial collateral ligament (MCL) and ACL plus posterolateral corner (PLC) injuries in elite athletes and, in a subgroup analysis of male professional soccer players, to compare career length and competition level after combined ACL+MCL or ACL+PLC surgeries with a cohort who underwent isolated ACL reconstruction (ACLR).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A consecutive cohort of elite athletes undergoing combined ACL+MCL and ACL+PLC surgery was analyzed between February 2001 and October 2019. A subgroup of male elite soccer players from this population was compared with a previously identified cohort having had isolated primary ACLR without other ligament surgery. A minimum 2-year follow-up was required. Outcome measures were career length and competition level.

RESULTS

A total of 98 elite athletes met the inclusion criteria, comprising 50 ACL+PLC and 48 ACL+MCL surgeries. The mean career length after surgical treatment of combined ACL+MCL and ACL+PLC injuries was 4.5 years. Return-to-play (RTP) time was significantly longer for ACL+PLC injuries (12.8 months; P = .019) than for ACL+MCL injuries (10.9 months). In the subgroup analysis of soccer players, a significantly lower number of players with combined ACL+PLC surgery were able to RTP (88%; P = .003) compared with 100% for ACL+MCL surgery and 97% for isolated ACLR, as well as requiring an almost 3 months longer RTP timeline (12.9 months; P = .002) when compared with the isolated ACL (10.2 months) and combined ACL+MCL (10.0 months) groups. However, career length and competition level were not significantly different between groups.

CONCLUSION

Among elite athletes, the mean career length after surgical treatment of combined ACL+MCL and ACL+PLC injuries was 4.5 years. Professional soccer players with combined ACL+PLC surgery returned at a lower rate and required a longer RTP time when compared with the players with isolated ACL or combined ACL+MCL injuries. However, those who did RTP had the same career longevity and competition level.

Valgus malalignment causes increased forces on a medial collateral ligament reconstruction under dynamic valgus loading: A biomechanical study

PURPOSE

To investigate the forces on a medial collateral ligament (MCL) reconstruction (MCLR) relative to the valgus alignment of the knee.

METHODS

Eight fresh-frozen human cadaveric knees were subjected to dynamic valgus loading at 400 N using a custom-made kinematics rig. After resection of the superficial medial collateral ligament, a single-bundle MCLR with a hamstring tendon autograft was performed. A medial opening wedge distal femoral osteotomy was performed and fixed with an external fixator to gradually adjust the alignment in 5° increments from 0° to 10° valgus. For each degree of valgus deformity, the resulting forces acting on the MCLR were measured through a force sensor and captured in 15° increments from 0° to 60° of knee flexion.

RESULTS

Irrespective of the degree of knee flexion, increasing valgus malalignment resulted in significantly increased forces acting on the MCLR compared to neutral alignment (p < 0.05). Dynamic loading at 5° valgus resulted in increased forces on the MCLR at all flexion angles ranging between 16.2 N and 18.5 N (p < 0.05 from 0° to 30°; p < 0.01 from 45° to 60°). A 10° valgus malalignment further increased the forces on the MCLR at all flexion angles ranging between 29.4 N and 40.0 N (p < 0.01 from 0° to 45°, p < 0.05 at 60°).

CONCLUSION

Valgus malalignment of the knee caused increased forces acting on the reconstructed MCL. In cases of chronic medial instabilities accompanied by a valgus deformity ≥ 5°, a realigning osteotomy should be considered concomitantly to the MCLR to protect the graft and potentially reduce graft failures.

LEVEL OF EVIDENCE

Level III.

Reconstruction of the Medial Collateral Ligament Complex With a Flat Allograft Semitendinosus Tendon

The aim of this Technical Note is to reconstruct the medial collateral ligament complex with the superior medial collateral ligament and posterior oblique ligament as anatomically as possible. An allograft or contralateral semitendinosus autograft is used for anatomic reconstruction of the superior medial collateral ligament and posterior oblique ligament. After bony fixation, the tendon bundles are sutured to the remnants of the medial collateral ligament complex. Thus, the tubular grafts are pulled apart to form a flat shape that resembles that of the normal medial ligaments.

[Injuries of the medial side of the knee : When and how should they be treated?]

Different medial structures are responsible for restraining valgus rotation, external rotation, and anteromedial rotation. When injured this can result in various degrees of isolated and combined instabilities. In contrast to earlier speculation, the posterior oblique ligament (POL) is no longer considered to be the main stabilizer of anteromedial rotatory instability (AMRI). Acute proximal medial ruptures are typically managed conservatively with very good clinical results. Conversely, acute distal ruptures usually require a surgical intervention. Chronic instabilities mostly occur in combination with instabilities of the anterior cruciate ligament (ACL). The clinical examination is a particularly important component in these cases to determine the indications for surgery for an additional medial reconstruction. In cases of severe medial and anteromedial instabilities, surgical treatment should be considered. Biomechanically, a combined medial and anteromedial reconstruction appears to be superior to other reconstruction methods; however, there is currently a lack of clinical studies to confirm this biomechanical advantage.

[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.

[Treatment of acute injury of the anterior cruciate ligament : Always only reconstruction?]

The aim of treatment of a ruptured anterior cruciate ligament (ACL) is the return of the patient to an acceptable level of activity without giving way phenomena as well as adequate treatment of prognostically relevant concomitant lesions. The treatment of acute ACL ruptures can be either early reconstruction or a primary physiotherapy with optional later reconstruction. Which path is taken depends on possible concomitant injuries that require early surgical intervention (e.g., repairable meniscal injury or distal rupture of the medial collateral ligament) and on patient-specific factors (age, level of activity). Isolated ruptures of the ACL can also be primarily treated without surgery. Then the injured knee joint should first be so far conditioned by rehabilitative measures that pain, swelling and posttraumatic restriction of movement are improved and neuromuscular training can be started. A screening test consisting of jumping tests, patient-reported outcome measures and the testing for giving way phenomena can be suitable to differentiate compensators (copers) from noncompensators (non-copers). Surgical reconstruction of the ACL should be recommended to non-compensators in the sense of participatory decision-making. Activity modification (adapter) can also be considered as a treatment strategy. If instability events (giving way) or secondary meniscal lesions occur during nonsurgical therapy, cruciate ligament reconstruction should be considered.

Association of medial collateral ligament complex injuries with anterior cruciate ligament ruptures based on posterolateral tibial plateau injuries

BACKGROUND

The combined injury of the medial collateral ligament complex and the anterior cruciate ligament (ACL) is the most common two ligament injury of the knee. Additional injuries to the medial capsuloligamentous structures are associated with rotational instability and a high failure rate of ACL reconstruction. The study aimed to analyze the specific pattern of medial injuries and their associated risk factors, with the goal of enabling early diagnosis and initiating appropriate therapeutic interventions, if necessary.

RESULTS

Between January 2017 and December 2018, 151 patients with acute ACL ruptures with a mean age of 32 ± 12 years were included in this study. The MRIs performed during the acute phase were analyzed by four independent investigators-two radiologists and two orthopedic surgeons. The trauma impact on the posterolateral tibial plateau and associated injuries to the medial complex (POL, dMCL, and sMCL) were examined and revealed an injury to the medial collateral ligament complex in 34.4% of the patients. The dMCL was the most frequently injured structure (92.2%). A dMCL injury was significantly associated with an increase in trauma severity at the posterolateral tibial plateau (p < 0.02) and additional injuries to the sMCL (OR 4.702, 95% CL 1.3-133.3, p = 0.03) and POL (OR 20.818, 95% CL 5.9-84.4, p < 0.0001). Isolated injuries to the sMCL were not observed. Significant risk factors for acquiring an sMCL injury were age (p < 0.01) and injury to the lateral meniscus (p < 0.01).

CONCLUSION

In about one-third of acute ACL ruptures the medial collateral ligament complex is also injured. This might be associated with an increased knee laxity as well as anteromedial rotational instability. Also, this might be associated with an increased risk for failure of revision ACL reconstruction. In addition, we show risk factors and predictors that point to an injury of medial structures and facilitate their diagnosis. This should help physicians and surgeons to precisely diagnose and to assess its scope in order to initiate proper therapies. With this in mind, we would like to draw attention to a frequently occurring combination injury, the so-called "unlucky triad" (ACL, MCL, and lateral meniscus). Level of evidence Level III Retrospective cohort study.

Editorial Commentary: The Timing and Treatment of Combined Anterior Cruciate Ligament-Medial Collateral Ligament Injuries: Conservative Management, Early Repair, Augmentation, and Delayed Reconstruction of the Medial Collateral Ligament

Medial collateral ligament (MCL) injuries are commonly encountered in conjunction with anterior cruciate ligament injuries. MCL tears do not universally heal, and residual MCL laxity is not always well tolerated. Although residual MCL laxity results in excess stress on an anterior cruciate ligament reconstruction and may require additional treatment, relatively little interest has been paid to concomitant treatment. Adherence to the dogma of universal conservative treatment of MCL tears in this setting squanders opportunities for preservation of native anatomy and improvements in patient outcomes. Although we currently lack the necessary information to provide evidence-based decision making for combined injuries, the time has come to renew both clinical interest and research interest in pursuing better management of these injuries in high-demand patients.

Treating Combined Anterior Cruciate Ligament and Medial Collateral Ligament Injuries Operatively in the Acute Setting Is Potentially Advantageous

Combined injury of the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) remains among the most common knee injury patterns in orthopaedics. Optimal treatment of grade III MCL injuries is still debated, especially when combined with ACL injury. Most patients with these severe injuries are treated conservatively for at least 6 weeks to allow for MCL healing, followed by delayed ACL reconstruction. Although acute treatment of the MCL was common in the 1970s, postoperative stiffness was frequently reported. Moreover, studies of such treatment failed to show clinical benefits of surgical over conservative treatment, and the MCL exhibited intrinsic healing capacity, leading to the consensus that all MCL injuries are treated conservatively. The current delayed treatment algorithm for ACL-MCL injuries has several disadvantages. First, MCL healing may be incomplete, resulting in residual valgus laxity that places the ACL graft at greater risk of failure. Second, delayed treatment lengthens the overall rehabilitation period, thereby prolonging the presence of atrophy and delaying return to preinjury activity levels. Third, the initial healing period leaves the knee unstable for longer and risks further intra-articular damage. Acute simultaneous surgical treatment of both ligaments has the potential to avoid these shortcomings. This article will review the evolution of treatment of ACL-MCL injuries and explain how it shifted toward the current treatment algorithm. We will (1) discuss why the consensus shifted, (2) discuss the shortcomings of the current treatment plan, (3) discuss the potential advantages of acute simultaneous treatment, and (4) present an overview of the available literature.

Effect of Rehabilitation Physical Training on PE Teaching Sports Injury under Ultrasonic Examination

In order to solve the problem of the effect of rehabilitation physical training on physical education teaching injury, a method based on ultrasonic examination of rehabilitation physical training on physical education teaching injury effect observation method is proposed. In this method, the ISOMED isokinetic muscle strength test, the body shape test, the balance ability test, the lower limb explosive power test, and other methods are used to evaluate the knee joint of patients systematically, and the specific rehabilitation physical training plan is formulated to achieve the treatment purpose. The experimental results show that after the targeted training, a series of indicators on the affected side increase significantly: the power increases by 45.6%, the force increases by 8.3%, and the speed increases by 38.7%. It is concluded that the muscle strength, shape, balance ability, and lower limb explosive power of patients are significantly improved, which lays a solid foundation for athletes to recover smoothly and achieve good competition results.

Dynamic Ultrasound Can Accurately Quantify Severity of Medial Knee Injury: A Cadaveric Study

Purpose

To quantify the severity of medial knee injuries based on medial compartment gapping as measured by stress ultrasonography.

Methods

In 8 cadaveric knees, the distance between the medial tibial and femoral condyles was measured using ultrasonography. These measurements were obtained in the intact state and repeated after open sequential transection of the superficial medial collateral ligament (sMCL), deep medial collateral ligament (dMCL), posterior oblique ligament (POL), and arthroscopic transection of the anterior cruciate ligament (ACL). Knees were evaluated at 0° and 20° of knee flexion using the Telos device under 0 N and 100 N of valgus force. Receiver operating characteristic curve analysis and the DeLong test were used to determine whether measurements could distinguish between successive severity of MCL injury after identifying the optimal cutoff value for each injury state.

Results

Of the 8 cadaveric knees included in this study, 3 were male and 5 were female. The mean age was 58 ± 11 years (range 48-82 years). When measured using ultrasonography at 20° knee flexion with valgus load, the medial tibiofemoral distance significantly increased with increasing severity of medial knee injury (P values ranging from .049 to <.001). The optimal cutoff values for distinguishing between an intact knee and sMCL injury were 8.3 mm (area under the curve [AUC] = 0.98), between sMCL and dMCL injury 9.9 mm (AUC = 0.89), dMCL and POL 16.7 mm (AUC = 0.88), and POL and ACL 18.6 mm (AUC = 0.84). When we compared combined intact and sMCL-transected stages with dMCL-transected stage, the optimal cut-off point to differentiate stable from unstable injuries was equal to 13.8 mm of medial tibiofemoral distance (AUC = 0.97; sensitivity = 100%; specificity = 94.1%).

Conclusions

Dynamic ultrasonographic assessment can accurately quantify the severity of medial knee ligament injury based on medial compartment gapping. In our study, we found medial tibiofemoral distance >13.8 mm at 20° knee flexion under valgus force indicates the presence of dMCL injury with a diagnostic accuracy of 0.97.

Clinical Relevance

Dynamic ultrasonography can quantify severity of medial knee injury without radiation and at point of care in multiple clinical settings.

Current concepts on management of medial and posteromedial knee injuries

Traditionally, while managing ligament injuries around the knee, medial side injuries are frequently overlooked or considered 'benign' with very little influence on overall knee stability outcomes. However, much has changed in the recent past, and like the lateral side of the knee, it is gaining considerable attention. It is now well known that the Medial collateral ligament and Posteromedial corner are fundamentally two distinct structures that differ in anatomy and biomechanics. When it comes to decision making between conservative versus operative approach for medial side injuries, treating orthopaedic surgeons are subjected to walking on a thin line trying to balance between potential residual laxity and joint stiffness. This review will delve into some of the recent works focusing on the medial side injuries and discuss the evolving concepts.