Multiligament Knee Injury

A High Grade of Postoperative Knee Laxity Is Associated With an Increased Hazard of Revision Surgery: A Cohort Study of 4697 Patients With Primary ACL Reconstruction

BACKGROUND

There is still debate regarding the association between arthrometric knee laxity measurements and subjective knee outcome and revision surgery after primary anterior cruciate ligament reconstruction (ACLR).

PURPOSE

To assess whether arthrometric knee laxity (measured with the KT-1000 arthrometer) 6 months after primary ACLR was associated with the 1-, 2-, and 5-year subjective knee outcomes or revision ACLR at a 5-year follow-up.

STUDY DESIGN

Cohort study, Level of evidence 3.

METHODS

Patients who underwent primary ACLR with a hamstring tendon autograft at the authors' institution between January 1, 2005, and December 31, 2017, with no concomitant ligamentous injuries, were identified. Anterior knee laxity (KT-1000 arthrometer, 134 N) was assessed 6 months postoperatively. The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and 1, 2, and 5 years postoperatively. Patients who underwent revision ACLR at any institution in the country within 5 years of primary surgery were identified through the Swedish National Knee Ligament Registry.

RESULTS

A total of 4697 patients (54.3% male) with available KT-1000 arthrometer measurements were included (normal: side-to-side [STS] ≤2 mm, 3015 [64.2%]; nearly normal: STS 3-5 mm, 1446 [30.8%]; abnormal: STS >5 mm, 236 [5.0%]). The only significant difference in subjective knee outcome between the groups was for the KOOS Symptoms subscale at the 1-year follow-up (STS ≤2 mm, 79.9 ± 16.2; STS 3-5 mm, 82.5 ± 14.8; STS >5 mm, 85.1 ± 14.2; P < .001). No other significant differences between the groups were found preoperatively or at 1, 2, or 5 years postoperatively for any of the KOOS subscales. The hazard for revision ACLR within 5 years of the primary surgery was significantly higher for the groups with an STS of 3 to 5 mm (6.6%; 95/1446) (hazard ratio [HR], 1.42; 95% CI, 1.07-1.87; P = .01) and an STS >5 mm (11.4%; 27/236) (HR, 2.61; 95% CI, 1.69-4.03; P < .001) compared with the group with an STS ≤2 mm (3.8%; 116/3015).

CONCLUSION

A high grade of postoperative knee laxity (STS 3-5 mm and STS >5 mm) 6 months after primary ACLR was associated with an increased hazard of revision ACLR within 5 years, but it was not associated with an inferior subjective knee outcome.

Contribution of the Medial Hamstrings to Valgus Stability of the Knee

Background

Multiligament knee injuries involving the medial side are common. When performing surgical reconstruction, use of the medial hamstrings (HS) as grafts remains controversial in this setting.

Purpose

To determine the role of the medial HS in stabilizing the valgus knee for different types of medial-sided knee injury.

Study Design

Controlled laboratory study.

Methods

A biomechanical study on 10 cadaveric knees was performed. Valgus load (force moment of 10 N/m) was applied at 0°, 30°, and 60° of flexion, and the resultant rotation was recorded using an optoelectronic motion analysis system. Measurements were repeated for 4 different knee states: intact knee, superficial medial collateral ligament (sMCL) injury, deep medial collateral ligament (dMCL) injury, and posterior oblique ligament (POL) injury. For each state, 4 loading conditions (+ loaded; - unloaded) of the semitendinosus (ST) and gracilis (GRA) tendons were tested: ST+/GRA+, ST+/GRA-, ST-/GRA+, and ST-/GRA-.

Results

At 0° of flexion, combined unloading of the ST and GRA (ST-/GRA-) increased valgus laxity on the intact knee compared with the ST+/GRA+ condition (P < .05). For all medial-sided injury states (isolated sMCL; combined sMCL and dMCL; and combined sMCL, dMCL, and POL damage), ST-/GRA- increased valgus laxity at 0° and 30° of flexion versus ST+/GRA+ (P < .05 for all). The absolute value of valgus laxity increased with the severity of medial-sided ligament injury. Isolated ST unloading increased valgus laxity for the intact knee and the MCL-injured knee (combined sMCL and dMCL) at 0° of flexion (P < .05 vs ST+/GRA+). Isolated unloading of the GRA had no effect on valgus knee stability.

Conclusion

The medial HS tendons contributed to the stabilization of the knee in valgus, and this was even more important when the medial side was severely affected (POL damage). This stabilizing effect was greater between 0° and 30°, in which the POL is the main valgus stabilizer.

Clinical Relevance

When deciding on graft selection for multiligament knee injury reconstruction, the surgeon should be aware of the effect of harvesting the medial HS tendon on valgus laxity.

Presentation and Surgical Management of Multiple Ligament Knee Injuries: A Multicenter Study from the Surgical Timing and Rehabilitation (STaR) Trial for MLKIs Network

BACKGROUND

Multiple ligament knee injuries (MLKIs) represent a spectrum of injury patterns that are often associated with concomitant musculoskeletal and neurovascular injuries, complex treatment, and postoperative complications. However, there has not been high-level evidence describing the presentation and treatment of MLKIs. The purpose of this multicenter retrospective study was to describe characteristics of MLKIs, their management, and related complications using a pathoanatomic MLKI classification system based on the Schenck Knee Dislocation classification system.

METHODS

This review identified and analyzed MLKIs that occurred between 2011 and 2015. Cases with an MLKI were included in this study if there was a complete tear of ≥2 ligaments and at least 1 ligament was repaired or reconstructed. Cases in which a ligament was deemed clinically incompetent due to a partial ligament tear and required surgical repair or reconstruction were considered equivalent to grade-III tears for inclusion and classification. Demographic information, the mechanism of injury, times from injury to presentation to an orthopaedic surgeon and to surgery, the ligament injury pattern, associated injuries, surgical procedures, and complications were captured. Data were analyzed descriptively.

RESULTS

A total of 773 individuals from 14 centers who underwent surgery for an MLKI were reviewed. The mean age of the individuals was 30.5 ± 12.7 years, and 74.2% were male. The most common mechanism involved sports (43.2%). The median time from injury to presentation to the orthopaedic surgeon was 11 days (interquartile range [IQR], 3 to 48 days), and the time to initial ligament surgery was 64 days (IQR, 23 to 190 days). While the most common injury patterns were an anterior cruciate ligament tear combined with either a medial-sided (MLK 1-AM, 20.7%) or lateral-sided (MLK 1-AL, 23.2%) injury, one-third (34.7%) were bicruciate injuries. Associated injuries most often involved nerves (18.5%) and tendons (15.6%). The method of surgical intervention (repair versus reconstruction), external fixator use, and staging of procedures varied by MLKI classification. Loss of motion (11.4%) was the most common postoperative complication.

CONCLUSIONS

A better understanding of the clinical characteristics and management of the various MLKI patterns can be used to support clinical decision-making and individualized treatment of these complex injuries, and may ultimately lead to enhanced outcomes and reduced associated risks.

LEVEL OF EVIDENCE

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

High Levels of Satisfaction and Adequate Patient-Reported Outcomes After Operative Reconstruction of Multiligament Knee Injury With Allograft Among Patients Aged 40 Years and Older

Purpose

To describe injury characteristics and patient-reported outcomes (PROs) among patients aged 40 years and older who underwent allograft reconstruction for multiligament knee injury (MLKI).

Methods

Records of patients aged 40 years and older who underwent allograft multiligament knee reconstruction at a single institution between 2007 and 2017 with a minimum of 2 years of follow-up were retrospectively reviewed. Demographic information, concomitant injuries, patient satisfaction, and PROs including International Knee Documentation Committee and Marx activity scores were obtained.

Results

Twelve patients were included with a minimum follow-up time of 2.3 years (mean, 6.1; range, 2.3-10.1 years) and a mean age at surgery of 49.8 years. Seven patients were male, and the most common mechanism of injury was sport-related. The most frequently reconstructed MLKIs were anterior cruciate ligament and medial collateral ligament (4), anterior cruciate ligament and posterolateral corner (2), and posterior cruciate ligament and posterolateral corner (2). The majority of patients reported satisfaction with their treatment (11). Median International Knee Documentation Committee and Marx scores were 73 (interquartile range, 45.5-88.0) and 3 (interquartile range 0-5), respectively.

Conclusions

Patients aged 40 years and older can expect a high level of satisfaction and adequate PROs at 2-years follow-up after operative reconstruction for a MLKI with allograft. This demonstrates that allograft reconstruction for a MLKI in older patients may have clinical utility.

Level of Evidence

IV, therapeutic case series.

Predictors of Mid- to Long-Term Outcomes in Patients Experiencing a Knee Dislocation: A Systematic Review of Clinical Studies

Knee dislocations (KDs) are devastating injuries for patients and present complex challenges for orthopaedic surgeons. Although short-term outcomes have been studied, there are few long-term outcomes of these injuries available in the literature. The purpose of this study is to determine factors that influence mid- to long-term clinical outcomes following surgical treatment of KD. A review of the current literature was performed by searching PubMed, the Cochrane Library, and Embase to identify clinical studies published from 2010 to 2019 with a minimum 2-year follow-up that reported outcomes following surgical treatment of KDs. Ten studies (6 level III, 4 level IV) were included. At mid- (2-10 y) to long-term (>10 y) follow-up, concomitant arterial, cartilage, and combined meniscus damage were predictive factors for inferior Lysholm and International Knee Documentation Committee (IKDC) scores when compared with patients without these associated injuries. Although concomitant neurological damage may influence short-term outcomes due to decreased mobility, at longer follow-up periods it does not appear to predict worse clinical outcomes when compared with patients without concomitant neurological injury. Frank and polytrauma KDs have been associated with worse mid- to long-term outcomes when compared with transient and isolated KDs. Patients who underwent surgery within 6 weeks of trauma experienced better long-term outcomes than those who underwent surgery longer than 6 weeks after the initial injury. However, the small sample size of this study makes it difficult to make valid recommendations. Lastly, female sex, patients older than 30 years at the time of injury and a body mass index (BMI) greater than 35 kg/m² are factors that have been associated with worse mid- to long-term Lysholm and IKDC scores. The results of this review suggest that female sex, age >30 years, BMI >35 kg/m², concomitant cartilage damage, combined medial and lateral meniscal damage, KDs that do not spontaneously relocate, and KDs associated with polytrauma may predict worse results at mid- to long-term follow-up.

Inclusion of open injuries in an updated Schenck classification of knee dislocations based on a global Delphi consensus study

OBJECTIVES

Knee dislocations (KDs) are complex injuries defined as incongruity of the tibiofemoral joint, which leads to tears of two or more of the main stabilising knee ligaments, and they are often associated with damage to surrounding soft tissue or neurovascular structures. A classification system for these injuries should be simple and reproducible and allow communication among surgeons for surgical planning and outcome prediction. The aim of this study was to formulate a list of factors, prioritised by high-volume knee surgeons, that should be included in a KD classification system.

METHODS

A global panel of orthopaedic knee surgery specialists participated in a Delphi process. The first survey employed 91 orthopaedic surgeons to generate a list of patient- and system-specific factors that should be included in a KD classification system that may affect surgical planning and outcomes. This list was subsequently prioritised by 27 identified experts (mean 15.3 years of experience) from Brazil (n = 9), USA (n = 6), South Africa (n = 4), India (n = 4), China (n = 2), and the United Kingdom (n = 2). The items were analysed to find factors that had at least 70% consensus for inclusion in a classification system.

RESULTS

Of the 12 factors identified, four (33%) achieved at least 70% consensus for inclusion in a classification system. The factors deemed critical for inclusion in a classification system included vascular injuries (89%), common peroneal nerve injuries (78%), number of torn ligaments (78%), and open injuries (70%).

CONCLUSION

Consensus for inclusion of various factors in a KD classification system was not easily achieved. The wide geographic distribution of participants provides diverse insight and makes the results of the study globally applicable. The most important factors to include in a classification system as determined by the Delphi technique were vascular injuries, common peroneal nerve injuries, number of torn ligaments, and open injuries. To date, the Schenck anatomic classification system most accurately identifies these patient variables with the addition of open injury classification. The authors propose to update the Schenck classification system with the inclusion of open injuries as an additional modifier, although this is only a small step in updating the classification, and further studies should evaluate the inclusion of more advanced imaging modalities. Future research should focus on integrating these factors into useful existing classification systems that are predictive of surgical treatment and patient outcomes.

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.

Cartilage and Meniscus Injuries Are More Common in Patients Undergoing Delayed Multiligament Reconstruction

The purpose of this study was to describe the pattern of meniscus and cartilage pathology in multiligament knee injuries (MLKIs) and determine the relationship between surgical timing and injury mechanism with degree of intra-articular injury. Patients with surgically treated MLKIs over a 15-year period were retrospectively reviewed and grouped based on surgical intervention, time to intervention, and injury mechanism. The presence or absence of meniscus and chondral injury were recorded at the time of surgery. Surgical intervention within 6 weeks of injury was deemed acute, while surgery occurring more than 6 weeks from injury was classified as delayed. Over the 15-year study period, 207 patients with MLKIs were identified. Compared with acutely managed patients, the delayed intervention group had significantly more meniscus (p = 0.03) and cartilage (p < 0.01) pathology. Meniscus injury rates in MLKIs sustained during sporting activity did not differ from nonsporting injuries (p = 0.63). However, the nonsporting group had significantly more chondral injuries (p < 0.01). High-energy injury mechanism was associated with increased cartilage (p = 0.02), but not meniscus (p = 0.61) injury rates. In conclusion, surgical reconstruction of MLKIs delayed for more than 6 weeks was associated with increased meniscus and cartilage pathology.

External fixation increases complications following surgical treatment of multiple ligament knee injuries

PURPOSE

The purpose of this study was to review post-operative complications after surgical intervention of MLKIs within the first 6 months to be better able to counsel patients before surgical intervention.

METHODS

All patients who underwent surgical reconstruction for a MLKI at one institution from 2009 to 2018 were included in this study. A retrospective review was performed of all patients and post-operative complications were recorded, including motion loss (which included > 10 degree flexion loss or > 3 degree extension loss), hematoma formation, infection, iatrogenic vascular or nerve injury, deep vein thrombosis (DVT), pulmonary embolism (PE), skin lesions, symptomatic hardware, recurrent ligamentous laxity, and need for additional surgery. Knee ligament injuries were classified based on the Schenck Knee Dislocation (KD) Classification.

RESULTS

A total of 136 patients were included in this study, 83 with KD I injuries, 40 with KD III injuries, 9 with KD IV injuries, and 4 with KD V injuries. Of these total patients, 48 (35.5%) sustained a post-operative complication: 11 out of 133 (8.3%) from 0 to 1 week, 46 out of 132 (34.8%) from 1 week to 1 month, 28 out of 124 (22.6%) from 1 to 3 months, and 26 out of 121 (21.5%) from 3 to 6 months. Out of the total complications, 99 (78.5%) occurred at 1 week-3 months post-operation. Patients who had an external fixator placed at initial injury were more likely to sustain a post-operative complication. The most common complication was motion loss in 39 (28.6%) patients. There was a significant difference in mean number of complications between the KD I and KD III groups, as well as the KD III and KD IV-V groups. There was no significant difference in the overall prevalence of post-operative complications or occurrence of motion loss with KD grade.

CONCLUSION

The main finding of this study was 48 (35.5%) patients sustained a complication after surgical treatment of MLKIs, with 99 (78.5% of all complications) complications occurring at 1 week-3 months post-operation. Patients who had an external fixator placed at initial injury were more likely to sustain a post-operative complication. The most common post-operative complication was motion loss in 39 (28.6%) patients. The KD grade was not associated with post-operative development of motion loss, but KD III had a significantly greater mean number of complications than KD I or KD IV-V grades.

LEVEL OF EVIDENCE

IV.

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.

Current concepts in the assessment and management of multiligament injuries of the knee

Multiligament knee injuries (MLKIs), though rare, pose significant challenges to the patient and surgeon. They often occur in the setting of high-velocity trauma and are frequently associated with concomitant intra- and extra-articular injuries, the most immediately devastating of which is vascular compromise. A detailed evaluation is required when acute or chronic MLKIs are suspected, and stress radiography, MRI and angiography are valuable adjuncts to a thorough clinical examination. Surgical treatment is widely regarded as superior to non-surgical management and has been demonstrated to improve functional outcome scores, return to work, and return to sport rates, though the incidence of post-traumatic osteoarthritis remains high in affected knees. However, acceptable results have been obtained with conservative management in populations where surgical intervention is not feasible. Early arthroscopic single-stage reconstruction is currently the mainstay of treatment for these injuries, but some recent comparative studies have found no significant differences in outcomes. Recent trends in the literature on MLKIs seem to favour early surgery over delayed surgery, though both methods have distinct advantages and disadvantages. Due to the heterogeneity of the injury and the diversity of patient factors, treatment needs to be individualised, and a single best approach with regards to the timing of surgery, repair versus reconstruction, surgical technique and surgical principles cannot be advocated. There is much controversy in the literature surrounding these topics. Early post-operative rehabilitation remains one of the most important positive prognostic factors in surgical management and requires a dedicated team-based approach. Though outcomes of MLKIs are generally favourable, complications are abundant and precautionary measures should be implemented where possible. Low resource settings are faced with unique challenges, necessitating adaptability and pragmatism in tailoring a management strategy capable of achieving comparable outcomes.

Low rate of return to pre-injury level of sports after multi-ligament knee injury - Functional outcomes after MLKI

BACKGROUND

Multi-ligament knee injury (MLKI) is a rare but severe injury with potential devastating complications. The primary goal of this study was to investigate return to sports and work after MLKI. Secondary outcomes were patient reported outcome measures (PROMs), treatment, time between trauma, diagnosis and treatment, and neurovascular damage.

METHOD

A database search was performed to identify all patients with MLKI in our hospital (2010-2017). Pre-defined variables were collected from patient files and questionnaires. Multiple regression analysis was used to study the relationship between different variables and PROMs.

RESULTS

31 patients were included. The overall return to sports rate after a MLKI was 88.5%, but only 23.1% returned to their pre-injury level. 83.3% of the patients were able to return to work. Multiple regression analyses led to a significant prediction model for pain during rest (F(7,16) = 2.808, p = 0.041, R² = 0.355). Within this model, a higher age was a significant predictor for higher pain scores (p = 0.002). Age was also a significant (negative) predictor within the non-significant models for IKDC (p = 0.004) and Lysholm (p = 0.024). A delay between trauma and diagnosis of more than three months was seen in 32.3% of the patients.

CONCLUSIONS

This study showed a relatively high overall return to sports and work after MLKI, but less than a quarter returned to their pre-injury level of sports. An important finding was the substantial number of patients with a delay between trauma and diagnosis. This study contributes to more awareness and knowledge about MLKI among physicians, which is essential to reduce these delays.

Clinical studies of single-stage combined ACL and PCL reconstruction variably report graft tensioning, fixation sequence, and knee flexion angle at time of fixation

PURPOSE

In single-stage ACL-PCL reconstruction, there is uncertainty regarding the order of graft tensioning and fixation, as well as the optimal knee flexion angle(s) for graft fixation. A systematic review of clinical studies of single-stage combined ACL-PCL reconstruction was performed to determine whether a particular fixation sequence and/or knee flexion angle is associated with superior outcomes.

METHODS

A systematic review was performed according to PRISMA guidelines. All levels of evidence were included. All outcome measures were extracted, including physical examination values, radiographic measurements, and objective and subjective outcomes.

RESULTS

Of the 19 included studies, 17 tensioned and fixed the PCL before the ACL. Only four studies reported the methods/forces used for graft tensioning. Across studies, the ACL was fixed at variable knee flexion angles, from full extension to 70°. Conversely, 3 studies fixed the PCL at a knee flexion angle < 45°, while the remaining 16 studies fixed the PCL at a flexion angle > 70°. Patient-reported outcomes were qualitatively similar between groups.

CONCLUSIONS

This systematic review found considerable variability in graft tension, fixation sequence, and knee flexion angle at the time of fixation, with insufficient evidence to support specific surgical practices. Most commonly, the PCL is fixed before the ACL graft, with fixation occurring at a knee flexion angle between 70° and 90° and near full extension, respectively. The methodology for quantifying the forces applied for graft tensioning is rarely described. Given this clinical equipoise, future studies should consistently report these surgical details. Furthermore, prospective, randomized studies on the treatment of multiligament knee injuries are needed to improve outcomes in patients.

LEVEL OF EVIDENCE

IV.