Early surgery and number of injured ligaments are associated with postoperative stiffness following multi-ligament knee injury surgery: a systematic review and meta-analysis

Why do patients with isolated PCL rupture experience no subjective knee joint instability during walking? An in vivo biomechanical study

Objective

The aim of this study is to assess the kinematic changes in the knee joint during walking in patients with isolated PCL-deficiency (PCLD) to determine the presence of walking-related joint instability (mechanical instability-abnormal displacement form structural damage). Additionally, the study seeks to provide biomechanical insights into the observed differences between subjective and objective assessments.

Methods

35 healthy volunteers and 27 patients with isolated PCLD (both involved and uninvolved sides) were included in the study. All participants walked on a treadmill at a self-selected comfortable speed. An optical 3D motion capture system was employed to collect six degrees of freedom kinematic data of the knee joint during walking. Statistical Parametric Mapping (SPM) was employed, using independent and paired t-tests to evaluate differences between the healthy control group and the PCLD group, as well as between the involved and uninvolved sides, respectively.

Results

Compared with the healthy control group, posterior tibial displacement (the main indicator for anterior-posterior instability) of the involved limb was significantly decreased during 79%-94%. additionally, knee flexion angles of the involved limb were significantly increased compared with healthy control group during 0%-5% and 95%-99% of the gait cycle and significantly decreased during 66%-87%; In the uninvolved side, adaptive gait changes were observed, with knee flexion angles significantly reduced during 20%-50% and 64%-89% of the gait cycle and posterior tibial displacement significantly reduced during 60%-94% compared with the healthy control group; Compared to the uninvolved limb, the involved limb showed increased internal rotation during 62%-71% of the gait cycle and increased knee flexion during 8%-53%, with no significant differences in other dimensions.

Conclusion

From a biomechanical perspective, patients with PCL rupture exhibit no joint instability during walking. Compared to the healthy control group, the involved leg shows a significant reduction in posterior tibial displacement and a diminished range of knee flexion. Clinical evaluations of PCLD should incorporate dynamic functional assessments, thereby providing a more comprehensive basis for treatment decisions.

3D printing technology is a more accurate tool than an experienced surgeon in performing femoral bone tunnels in multi-ligament knee injuries

Purpose

Current surgical methods for multi-ligament knee reconstruction involve the creation of several reconstruction tunnels in the distal femur. However, the limited bone mass in the knee increases the risk of tunnel convergence. Increasing the accuracy of tunnel direction can minimize tunnel collision during anatomical reconstruction. 3D-printed patient-specific instrumentation (PSI) has gained prominence in orthopaedic surgery due to its precision. This study aims to compare the accuracy of PSI with that of the 'freehand' approach by an experienced surgeon for drilling the medial and lateral femoral tunnels while adhering to the recommended angulations for multi-ligament knee injuries.

Methods

Ten cadaveric knees underwent computerized tomography (CT) scans to identify anatomical femoral attachments of the lateral collateral ligament (LCL), popliteal tendon (PT), medial collateral ligament (MCL) and posterior oblique ligament (POL). Using Materialise Mimics Medical v25.0 software, virtual planning of a bone tunnel for each ligament was performed, and a total of four tunnels per knee were obtained. Ten PSIs were designed for five knees: five for the medial side and five for the lateral side. The first five knees were operated on via PSI, and the other five knees were operated on by an experienced surgeon using freehand drilling based on preoperative plans. The angular deviation and entry point were assessed by overlaying post-operative CT images onto preoperative CT images.

Results

In the freehand group, the median angular deviation was 22.3°, with an interquartile range (IQR) of 17.6-25.2°. The PSI group presented a significantly greater accuracy in angular deviation for femoral tunnels of 5.7°, with an IQR of 4-8.2° (p < 0.001). Compared with that in the preoperative planning group, the median entry point distance in the freehand group was 5.5 mm, with an IQR of 2.6-8.8 mm. The PSI group had a median entry point distance of 4.2 mm, with an IQR of 3.6-5.7 mm (p = n.s).

Conclusions

Compared with the freehand technique performed by an experienced surgeon, PSI demonstrated significantly greater accuracy in terms of the mean angular deviation.

Level of Evidence

Level V.

Timing of Surgery & Rehabilitation After Multiligamentous Knee Reconstruction

PURPOSE OF REVIEW

To provide an overview of the current evidence of the timing of surgery and rehabilitation after multiligamentous knee injuries (MLKIs) and offer insights into the ongoing multi-center randomized controlled study, the 'STaR trial'.

RECENT FINDINGS

Due to the complexity of the MKLIs, they are usually treated surgically with the goal of either repairing or reconstructing the injured ligaments. Although the current literature on MLKIs is relatively extensive, the consensus on the timing of surgery or rehabilitation following surgery for MLKIs is still lacking. While current literature mostly suggests early treatment, there is also evidence preferring delayed treatment. Furthermore, evidence on the timing of postoperative rehabilitation is limited. Thus, the current multi-center randomized controlled study, the 'STaR trial', is expected to respond to these questions by adding new high-level evidence. The MLKIs are often associated with knee dislocation and constitute a highly complex entity, including concomitant injuries, such as neurovascular, meniscal, and cartilaginous injuries. The treatment of MLKIs usually aims to either repair or reconstruct the injured ligaments, however, there is no general consensus on the timing of surgery or rehabilitation following an MLKI surgery. This current review stresses the need for more high-level research to address the paucity of evidence-based treatment guidelines for the treatment of complex MLKIs.

Knee joint dislocations-Current epidemiology and treatment in Germany

PURPOSE

Knee joint dislocations, though rare, present significant challenges due to potential complications like vascular and nerve damage, and are known to be often linked to sports injuries, accidents and obesity. This study aims to analyse the epidemiology, incidence and treatment approaches for knee dislocations in Germany from 2019 to 2022.

METHODS

This retrospective cohort study utilized data from the German Institute for the Hospital Remuneration System to examine knee dislocation cases across German medical institutions. Patient data coded under International Statistical Classification of Diseases and Related Health Problems 10 for 'knee dislocation' enabled detailed analysis by age, sex and surgical procedures categorized by operation and procedure codes. The Patient Clinical Complexity Level (PCCL) assessed complication severity.

RESULTS

Analysis of 1643 knee dislocation cases revealed an incidence rate of 0.44-0.54 per 100,000 inhabitants annually. During the years 2020 and 2021, there were fewer cases of knee dislocations. Male patients comprised 50%-56% of cases, with an average hospital stay of 11 days. Most cases were PCCL 0 (62%-72%) and predominantly affected patients aged 18-29 years. Anterior tibial dislocations were common among classified cases. Injuries included ligament ruptures, meniscus lesions and grade I soft-tissue injuries. Patients with pre-existing knee prostheses constituted 0%-16% annually. Treatment involved closed reduction, external fixation and surgeries like capsuloligamentous reconstructions and arthroscopic procedures. Revision knee arthroplasty was required in 2%-9% of cases, with obesity rates up to 7%.

CONCLUSIONS

This study provides valuable insights into the epidemiology, incidence and treatment of knee dislocations in Germany, with a focus on demographic risk factors, treatment complexities and the impact of obesity and knee prostheses. The findings emphasize the importance of specialized care in larger hospitals, comprehensive management of concomitant injuries and the need for improved coding accuracy. Future research should aim to refine treatment protocols.

LEVEL OF EVIDENCE

Level III.

A novel minimally invasive nonanatomical single-bundle medial collateral ligament reconstruction technique with a short isometric construct Achilles tendon allograft: A surgical description with clinical and radiological outcomes in multiligament knee injury patients

Purpose

Multiligament knee injuries (MLKIs) involve various ligaments in the knee. Current double-bundle anatomical reconstructions of the medial collateral ligament (MCL) increase the level of technical complexity, often resulting in the establishment of numerous bone tunnels and different fixation points with additional hardware. To overcome these limitations, we proposed a novel minimally invasive nonanatomical MCL reconstruction with one tibial tunnel in the metaphysis using Achilles allograft in the MLKI setting.

Methods

In a retrospective study, we enroled 24 patients with MLKIs who underwent a new single-strand short isometric construct (SIC) nonanatomical MCL reconstruction during 2020 and 2021. We fixed an Achilles allograft in one tunnel in the distal femur on the medial epicondyle and one tunnel in the metaphyseal part of the tibia using interference screws at 2 cm below the joint line between the anatomical insertion of the superficial MCL and the posterior oblique ligament. The patients underwent clinical and radiological assessment at the last follow-up, 1-2 years after the operation, including valgus stress radiographs, range of motion (ROM), Lysholm and International Knee Documentation Committee (IKDC) scores.

Results

The mean postoperative IKDC score was 77.8 (range, 50.1-86.6). The mean Lysholm score was 84.1 ± 11.9 (range, 96-59). The medial knee widening difference (i.e., mean side-to-side difference under valgus stress x-ray) was measured to be 1.2 mm on average. Only two patients (8%) had ROM limitation of 20° in knee flexion, one of which had surgery failure. Results showed a significant statistical difference between the patients' outcomes according to the number of involved ligaments.

Conclusions

This novel SIC-like technique with a single tibial metaphyseal tunnel demonstrated satisfactory patient-reported outcome measures, valgus stress radiographs, ROM and a low rate of knee stiffness and graft failure. While the number of injured ligaments in MLKI patients significantly influenced the outcomes, the results remained acceptable across all patients.

Level of Evidence

Level IV.

Effect of Timing of Surgery on the Outcomes and Complications in Multi-ligament Knee Injuries: An Overview of Systematic Reviews and A Meta-analysis

Background and Aims

Multi-ligament knee injuries (MLKI) are serious and challenging to manage. This study aimed to elucidate the impact of surgical timing on both early and long-term outcomes following an MLKI.

Methods

A comprehensive search strategy was employed across PubMed, Scopus, Web of Science, and the Cochrane Library. Studies were identified using a combination of relevant keywords encompassing "multi-ligament knee injury," "knee dislocation," "reconstruction," "repair," "surgery," and "timing," and their synonyms, along with appropriate Boolean operators. Selection of articles (systematic reviews and meta-analyses) adhered to predefined inclusion and exclusion criteria. Furthermore, a meta-analysis was conducted utilizing data extracted from primary studies.

Results

Early surgery for MLKI demonstrated a significant advantage over delayed surgery, reflected by significantly higher Lysholm scores (Mean Difference [MD] 3.51; 95% Confidence Interval [CI] 1.79, 5.22), IKDC objective scores (Mantel-Haenszel Odds Ratio [MH-OR] 2.95; 95% CI 1.30, 6.69), Tegner activity scores (MD 0.38; 95% CI 0.08, 0.69), and Mayer's ratings (MH-OR 5.47; 95% CI 1.27, 23.56). In addition, we found a significantly reduced risk of secondary chondral lesions (MH-OR 0.33; 95% CI 0.23, 0.48), lower instrumented anterior tibial translation in the early surgery group (MD -0.92; 95% CI -1.83, -0.01), but no significant difference was observed in the secondary meniscal tears, between the two groups. However, the early surgery group also exhibited a significantly increased risk of knee stiffness (MH-OR 2.47; 95% CI 1.22, 5.01) and a greater likelihood of requiring manipulation under anaesthesia (MH-OR 3.91; 95% CI 1.10, 13.87).

Conclusion

Early surgery for MLKI improves function, and stability, and reduces further articular cartilage damage, but increases the risk of stiffness.

Level of Evidence

IV.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-024-01224-1.

Outcomes after multiligament knee injury worsen over time: A systematic review and meta-analysis

PURPOSE

Multiligament knee injuries (MLKIs) are devastating injuries that can have life-long consequences. A management plan requires the decision to perform surgery or not, timing of surgery, consideration of repair versus reconstruction, reconstruction technique and reconstruction graft choice. The purpose of this study was to analyze development of clinical outcomes of MLKIs over time at a minimum of 2 years of follow-up.

METHODS

Four databases were queried for surgical outcome-based studies of MLKIs published from 01/2000 through 09/2022 with a minimum 2-year follow-up. Technique articles, nonoperative treatment, arthroplasty, pediatric and review articles were excluded. Study characteristics including design, number of patients, age, follow-up period, anatomical region and posterior-cruciate ligament (PCL)-based injury were collected. Primary outcomes were Lysholm, International Knee Documentation Committee (IKDC) outcome scores and Tegner activity score. Random-effects model analysis was performed.

RESULTS

After the application of inclusion and exclusion criteria, 3571 patients in 79 studies were included in the analysis. The mean age at surgery was 35.6 years. The mean follow-up was 4.06 years (range 2-12.7). The mean Lysholm score at 2-year follow-up was 86.09 [95% confidence interval [CI]: 82.90-89.28], with a yearly decrease of -0.80 [95% CI: -1.47 -0.13], (p = 0.0199). The mean IKDC at 2 years was 81.35 [95% CI: 76.56-86.14], with a yearly decrease of -1.99 [95% CI: -3.14 -0.84] (p < 0.001). Non-PCL-based injuries had a higher IKDC 83.69 [75.55-91.82] vs. 75.00 [70.75-79.26] (p = 0.03) and Lysholm score 90.84 [87.10-94.58] versus 84.35 [82.18-86.52] (p < 0.01) than PCL-based injuries, respectively.

CONCLUSION

According to the present systematic review and meta-analysis of MLKIs with minimum 2-year follow-ups, the patients who suffered an MLKI can expect to retain around 80-85% of knee function at 2 years and can expect a yearly deterioration of knee function, depending on the score used. Inferior outcomes can be expected for PCL-based injuries at 2 years postoperative.

LEVEL OF EVIDENCE

Level IV meta-analysis.

A slight degree of osteoarthritis appears to be present after anterior cruciate ligament reconstruction compared with contralateral healthy knees at a minimum of 20 years: A systematic review of the literature

Purpose

The aim of the present systematic review was to quantitatively synthesize the best literature evidence regarding osteoarthritis developing after anterior cruciate ligament reconstruction (ACLR), including only studies with a follow-up duration of at least 20 years.

Material and Methods

A systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines on four electronic databases (PubMed, Scopus, EMBASE and Cochrane Library). The outcome measures extracted from the studies were failure rate, subsequent knee surgery on the same knee, radiographic development of osteoarthritis measured with Kellgren-Lawrence, International Knee Documentation Committee (IKDC) radiographic score and Ahlbäck classification. The health of both the ACLR knee and the contralateral knee was compared.

Results

A total of 1552 patients were included in the study, of which 1290 (83.11%) were operated on using a patellar tendon graft, 190 (12.24%) with hamstrings, 27 (1.73%) with an iliotibial band and 45 (2.89%) with patellar tendon plus a ligament augmentation device (LAD). The mean age at the time of surgery was 25.18 ± 1.91 years, and the mean follow-up time was 23.34 ± 2.56 years. Analysing IDKC Score at final follow-up, ACLR Group showed a higher degree of OA compared with contralateral healthy knee (p < 0.01), but only 33.2% (324/976) of the patients showed a moderate to severe degree (Grade C or D) of osteoarthritis, while for Kellgren-Lawrence, ACLR Group showed a higher degree of OA compared with contralateral healthy knee (p < 0.01), but only 28.9% (196/678) of the patients showed a moderate to severe degree (Grade III or IV) of osteoarthritis. In total, 1552 patients were registered, 155 reruptures (9.98%) and a total of 300 (19.3%) new surgeries, of which 228 meniscectomy (14.69%), 21 (1.35%) knee arthroplasty and 17 (1.09%) hardware removal were recorded.

Conclusions

ACL reconstruction appears to result in mild osteoarthritis in the long term in most of the patients and only less than 33.2% develop a moderate to severe degree of knee OA according to IKDC radiographic score. A slight degree of osteoarthritis appears to be present in ACLR knees compared with contralateral healthy knees.

Level of Evidence

Level IV.

Multiligament knee injuries. Ten years' experience at a public university, level I Trauma Center

PURPOSE

To describe our institutional experience and results in the surgical management of multiligament knee injuries (MLKI).

MATERIALS AND METHODS

Retrospective series of MLKI consecutively operated on at a single, level I Trauma Center. Data on patients' baseline characteristics, injuries, treatments, and outcomes were recorded up to one-year follow-up. Recorded outcomes included the Tegner-Lysholm Knee Scoring Scale (TLKSS), return to work, and patient satisfaction.

RESULTS

MLKI incidence was 0.03% among 9897 orthopedic trauma admissions. Twenty-four patients of mean age 43.6 years were included in analysis. The mean Injury Severity Score was 12.6. Five patients presented with knee dislocations and six had fracture-dislocations, two of them open fractures. There was one popliteal artery injury requiring a bypass and four common peroneal nerve palsies. Staged ligamental reconstruction was performed in all cases. There were seven postoperative complications. The median TLKSS was 80 and, though patient satisfaction was high, and dissatisfaction was largely restricted to recreational activities (only 58.3% satisfied). Seventeen patients returned to their previous employment.

CONCLUSIONS

We found a high aggregation of fracture-dislocations secondary to road traffic accidents. One in four patients experienced complications, particularly stiffness. Complications were more common in cases involving knee dislocation. Most patients had good functional results, but 25% were unable to return to their previous work, which demonstrates the long-lasting sequelae of this injury.