Promising Outcomes of Suture Tape Augmentation in Quadriceps Tendon Autograft Anterior Cruciate Ligament Reconstruction

The management of anterior cruciate ligament (ACL) injuries continually evolves with new interest in all-sort tissue quadriceps tendon autograft, and new interest in suture tape augmentation of the graft, particularly in high-risk patients with young age; female sex; lower limb alignment, tibial, or femoral abnormalities; hyperlaxity; concomitant meniscal and/or additional ligamentous injuries; or participation in high-risk sports. Load sharing suture tape enhances biomechanical stability of the reconstructed ACL, especially during the initial ingrowth and ligamentization phase, and biomechanical evidence highlights reduced risk of graft elongation and failure under the loads encountered during daily physical activities and sport. Optimal tape tensioning could be in knee hyperextension, when the ACL is at maximal length, to avoid overconstraint. Two-year published outcomes of this technique are excellent. Current comparative studies, however, have not shown superiority. Additional controlled studies, and studies with longer term follow-up are needed, as well as comparison to extra-articular tenodesis augmentation.

Tibial plateau fractures are associated with poor functional outcomes and a low conversion rate to total knee arthroplasty

PURPOSE

The aim of this study was to analyse the functional outcome and the conversion rate to total knee arthroplasty (TKA) after surgically treated tibial plateau fractures (TPF).

METHODS

All patients undergoing surgical treatment of TPF at a single institution between January 2003 and December 2019 were retrospectively reviewed. The Knee injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity scale (TAS) were collected. The conversion rate to TKA was examined 2, 5, 7 and 10 years after surgical treatment of TPF.

RESULTS

Ninety-four patients, with a mean follow-up of 110.6 months (±60.0), were included in the functional outcome assessment. Mean KOOS scores were 75.4 for symptoms, 80.6 for pain, 84.3 for activities of daily living (ADL), 59.5 for sports and 61.3 for QOL. All subscales were significantly lower on the injured side compared with the contralateral leg. Lower KOOS was observed in patients with hardware removal and Schatzker type 5 and 6 injuries. Median TAS was postinjury (4) significantly lower than preinjury (5) (p < 0.001). The conversion rate to TKA was 6.3%, 10.9%, 11.7% and 12.2% after 2,5,7 and 10 years of follow-up, respectively. Patients undergoing TKA were older than patients with no conversion to TKA (2 years follow-up 53.8 vs. 64.5 years, p = 0.026).

CONCLUSION

TPFs decrease the function of the knee when compared with the contralateral side and to the preoperative condition. Bicondylar fractures are associated with worse functional outcomes. A conversion rate to TKA of 12.2% was found at 10 years follow-up.

LEVEL OF EVIDENCE

Level III.

Noninvasive and Reliable Quantification of Anteromedial Rotatory Knee Laxity: A Pilot Study on Healthy Individuals

BACKGROUND

Anteromedial rotatory instability (AMRI) of the knee is a complex and severe condition caused by injury to the anterior cruciate ligament and/or the medial collateral ligament. Clinical studies dealing with AMRI are rare, and objective measurements are nonexistent.

PURPOSE/HYPOTHESIS

The objectives of this study were, first, to quantify anteromedial rotatory knee laxity in healthy individuals using a noninvasive image analysis software and, second, to assess intra- and interrater reliability and equivalence in measuring anteromedial knee translation (AMT). It was hypothesized that AMT could be reliably quantified using a noninvasive image analysis software.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

This prospective proof-of-concept study included healthy individuals aged 16 to 40 years with no history of knee injury or surgery. Three adhesive surface markers were placed on predefined landmarks on the medial side of the knee. Three independent investigators examined anteromedial rotatory knee laxity with an anterior drawer test in different tibial rotations (neutral tibial rotation, 15° of external tibial rotation, and 15° of internal tibial rotation). The entire examination of each knee was recorded, and AMT including the side-to-side difference (SSD) was assessed using a freely available and validated image analysis software (PIVOT iPad application). Group comparisons were performed using a 1-way analysis of variance with Bonferroni-adjusted post hoc analysis. Intraclass correlation coefficients (ICCs) were calculated to assess inter- and intrarater reliability of AMT measurements. Equivalence of measurements was evaluated using the 2 one-sided t-test procedure.

RESULTS

Anteromedial rotatory knee laxity was assessed in 30 knees of 15 participants (53% male) with a mean age of 26.2 ± 3.5 years. In all 3 raters, the highest AMT was observed in neutral tibial rotation (range of means, 2.2-3.0 mm), followed by external tibial rotation (range of means, 2.0-2.4 mm) and internal tibial rotation (range of means, 1.8-2.2 mm; P < .05). Intrarater reliability of AMT (ICC, 0.88-0.96) and SSD (ICC, 0.61-0.96) measurements was good to excellent and moderate to excellent, respectively. However, interrater reliability was poor to moderate for AMT (ICC, 0.44-0.73) and SSD (ICC, 0.12-0.69) measurements. Statistically significant equivalence of AMT and SSD measurements was observed between and within raters for almost all testing conditions.

CONCLUSION

Anteromedial rotatory knee laxity could be quantified using a noninvasive image analysis software, with the highest AMT observed during neutral tibial rotation in uninjured individuals. Reliability and equivalence of measurements were good to excellent within raters and moderate between raters.

Lateral Extra-articular Tenodesis Does Not Decrease Graft Failure in Revision Anterior Cruciate Ligament Reconstruction When Combined With Quadriceps or Patellar Tendon Grafts

PURPOSE

To compare return-to-sport (RTS) rates, graft failure rates, and clinical outcomes in patients who underwent revision anterior cruciate ligament reconstruction (R-ACLR) with additional lateral extra-articular tenodesis (LET) versus isolated R-ACLR.

METHODS

A retrospective review of the medical records of patients who underwent R-ACLR with or without a modified Lemaire LET procedure was performed. Seventy-four patients with at least 2 years of follow-up who had high-grade positive pivot-shift test findings were included. Concomitant procedures such as meniscectomy and meniscal repair were collected, along with any complications and/or graft failure. The Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee Subjective Knee Form score were collected. The ability to RTS was defined as fully, partially, or not returned.

RESULTS

Of the patients, 39 underwent isolated R-ACLR (mean age ± standard deviation, 29.2 ± 12.2 years) whereas 35 underwent an additional LET procedure (mean age, 24.6 ± 7.4 years). The mean length of follow-up in the R-ACLR group was 56.6 ± 26.5 months compared with 44.3 ± 17.6 months in the R-ACLR-LET group (P = .02) (range, 24-120 months). Patient-reported outcome measures were higher in the R-ACLR-LET group, with the KOOS Activities of Daily Living (93.5 ± 2.0 vs 97.2 ± 1.6, P = .03) and KOOS Sport (63.0 ± 3.6 vs 74.3 ± 3.8, P = .05) subdomain scores reaching the level of statistical significance. No differences were found in the other KOOS subdomain scores or the International Knee Documentation Committee scores. Failure rates were not significantly different between the groups (12.8% for R-ACLR vs 11.4% for R-ACLR-LET, P = .99). There were 13 patients (72.2%) in the R-ACLR group and 14 patients (60.8%) in the R-ACLR-LET group who did not RTS.

CONCLUSIONS

R-ACLR with additional LET showed similar failure and RTS rates to isolated R-ACLR after failed ACLR. The R-ACLR-LET group showed better functional results with significantly higher KOOS subdomain scores for activities of daily living, as well as sports and recreation. However, this study was unable to recommend the modified Lemaire LET procedure to be routinely used in R-ACLR patients.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Anatomic repair and ligament bracing as an alternative treatment option for acute combined PCL injuries involving the posteromedial or posterolateral corner-results of a multicentre study

INTRODUCTION

Combined PCL injuries involving the posteromedial/-lateral corner (PMC/PLC) usually require surgical management. Literature shows controversy regarding the standards of treatment. Suture-augmented repair leads to excellent results in acute knee dislocations but has not been investigated clinically in combined PCL injuries. The purpose of this multicentre study was to evaluate the clinical outcome of this technique in acute combined PCL injuries.

MATERIALS & METHODS

N = 33 patients with acute combined PCL injuries involving the PMC/PLC were treated by one-stage suture repair with ligament bracing of the PCL and suture repair of the accompanying PMC/PLC injuries with/without ligament bracing or primary augmentation by semitendinosus autograft. Outcome was assessed by IKDC questionnaire, Lysholm Score, Tegner Activity Scale and KOOS. Additional PCL stress-radiography was performed.

RESULTS

N = 31 patients with combined PCL injuries (female: male = 7:24; age 39.1 ± 13.8 years) with a follow-up of 16.8 ± 9.6 months were finally evaluated. 18 had PMC injuries, 13 PLC injuries. 32.2% presented with accompanying meniscal tears (70% medial meniscus). 19.4% showed cartilage injuries grade III-IV. Complications included one infection and four knee stiffnesses. Three had symptomatic postoperative instability, all affiliated to the PLC group. The IKDC was 69.8 ± 16.5, Lysholm score 85 ± 14.4 and KOOS 89.7 ± 8.1. Median loss of activity (Tegner) was 0.89 ± 1.31. Comparing PMC and PLC, all scores showed a tendency towards more favourable outcomes in the PMC group (n.s.). Stress-radiography showed an overall side-to-side difference of 3.7 ± 3.8 mm. Subgroup evaluation showed statistically significant better results (p = 0.035) of PMC (2.5 ± 1.5 mm) versus PLC (5.8 ± 5.6 mm).

CONCLUSIONS

One-stage suture repair with ligament bracing is a viable technique for acute combined PCL injuries and predominantly leads to good and excellent clinical outcomes. Patients with PLC injuries show a tendency towards inferior outcomes and higher instability rates compared to PMC injuries. These results may help in therapy planning and counselling patients with these rare injury pattern.

LEVEL OF EVIDENCE

Level II.

The Posterior Tibial Slope Is Not Associated With Graft Failure and Functional Outcomes After Anatomic Primary Isolated Anterior Cruciate Ligament Reconstruction

BACKGROUND

Biomechanical studies have shown that an increased medial posterior tibial slope (MPTS) may affect anteroposterior knee laxity and tibial shear forces, ultimately increasing the risk for graft failure after anterior cruciate ligament (ACL) reconstruction. Previous clinical studies have, however, reported inconclusive results.

PURPOSE

The purpose of this study was to evaluate the relationship between the MPTS and graft failure as well as functional outcomes after anatomic primary isolated ACL reconstruction using a hamstring tendon autograft. It was hypothesized that an increased MPTS would be associated with a higher ACL graft failure rate. Furthermore, a higher MPTS would negatively correlate with functional outcomes in patients without ACL graft failure.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Consecutive patients who underwent isolated primary ACL reconstruction with an anteromedial portal drilling technique between January 2011 and December 2019 were retrospectively reviewed. The MPTS was measured on preoperative lateral knee radiographs. At a minimum of 24 months postoperatively, the ACL graft failure rate and patient-reported outcome measures (PROM; International Knee Documentation Committee subjective knee form, Lysholm score, Tegner Activity Scale, visual analog scale for pain and subjective instability) were evaluated. Differences in the MPTS between patients with and without ACL graft failure as well as the frequency of graft failure between those with an MPTS <12° and those with an MPTS ≥12° were assessed for statistical significance. Binary logistic regression analysis was performed to stratify the risk of graft failure with the following variables: MPTS, age at surgery, and sex. Correlation analysis was performed to evaluate the relationship between the MPTS and PROM in patients without ACL graft failure.

RESULTS

In total, 326 patients were included (median follow-up, 71.0 months [IQR, 49.0-104.0 months]). There was no significant difference in the MPTS between patients with and without graft failure (10.6°± 3.2° vs 11.2°± 2.8°, respectively; P = .264). Additionally, there was no significant difference in the frequency of graft failure between patients with an MPTS <12° and those with an MPTS ≥12° (15.6% vs 16.5%, respectively; P = .835). Binary logistic regression showed that younger age at the time of surgery (odds ratio, 1.069 [95% CI, 1.031-1.109]) was associated with graft failure; sex and MPTS were not associated with graft failure. In patients without ACL graft failure, there was no significant correlation between the MPTS and PROM.

CONCLUSION

In patients who underwent anatomic primary isolated ACL reconstruction, an increased MPTS was not associated with a higher rate of graft failure or inferior functional outcomes. Younger age was a significant nonmodifiable risk factor for ACL graft failure.

Risk for total knee arthroplasty after tibial plateau fractures: a systematic review

PURPOSE

Tibial plateau fractures (TPFs) may lead to posttraumatic osteoarthritis and increase the risk for total knee arthroplasty (TKA). The aim of this systematic review was to analyse the conversion rate to TKA after TPF treatment.

METHODS

A systematic search for studies reviewing the conversion rate to TKA after TPF treatment was conducted. The studies were screened and assessed by two independent observers. The conversion rate was analysed overall and for selected subgroups, including different follow-up times, treatment methods, and study sizes.

RESULTS

A total of forty-two eligible studies including 52,577 patients were included in this systematic review. The overall conversion rate of treated TPF to TKA in all studies was 5.1%. Thirty-eight of the forty-two included studies indicated a conversion rate under 10%. Four studies reported a higher percentage, namely, 10.8%, 10.9%, 15.5%, and 21.9%. Risk factors for TKA following TPF treatment were female sex, age, and low surgeon and hospital volume. The conversion rate to TKA is particularly high in the first 5 years after fracture.

CONCLUSION

Based on the studies, it can be assumed that the conversion rate to TKA is approximately 5%. The risk for TKA is manageable in clinical practice.

PROSPERO REGISTRATION NUMBER

CRD42023385311.

LEVEL OF EVIDENCE

IV.

Failure Rates and Complications After Multiple-Revision ACL Reconstruction: Comparison of the Over-the-Top and Transportal Drilling Techniques

Background

Multiple-revision anterior cruciate ligament reconstruction (ACLR) presents several technical challenges, often due to residual hardware, tunnel widening, malposition, or staged surgeries.

Purpose

To compare failure and complication rates between the over-the-top (OTT) and transportal drilling (TD) techniques in patients undergoing surgery for failed revision ACLR.

Study Design

Cohort study; Level of evidence, 3.

Methods

The medical records of patients with at least 2 revision ACLRs using either the OTT or TD technique were reviewed retrospectively. Data on patient demographics, graft characteristics, number of revisions, concomitant procedures, complications, and failures were collected. Between-group comparisons of continuous and categorical variables were conducted with the independent-samples t test and the Fisher exact or chi-square test, respectively.

Results

A total of 101 patients undergoing multiple-revision ACLR with OTT (n = 37, 37%) and TD (n = 64, 63%) techniques were included for analysis. The mean follow-up time was 60 months (range, 12-196 months). There were no significant differences in age, sex, body mass index, laterality, or follow-up length between groups (P > .05). Allograft was the graft used most frequently (n = 64; 67.3%) with no significant differences between groups in graft diameter (P > .05). There were no statistically significant differences between groups regarding rate of concurrent medial and lateral meniscus, cartilage, or lateral extra-articular procedures (P > .05). There was also no significant66 between-group difference in complication rate (OTT: n = 2 [5.4%]; TD: n = 8 [13%]) or graft failure rate (OTT: n = 4 [11%]; TD: n = 14 [22%]) (P > .05 for both).

Conclusion

The results of this study showed notably high failure and complication rates in challenging multiple-revision ACLR. Complication and failure rates were similar between techniques, demonstrating that the OTT technique is a valuable alternative that can be used in a revision ACLR, particularly as a single-stage approach when the single-stage TD technique is not possible.

Delayed multiligament PCL reconstruction is associated with a higher prevalence of intraarticular injury and may influence treatment

BACKGROUND

The aim of this study was to investigate differences in concomitant injury patterns and their treatment in patients undergoing early (≤ 12 weeks) and delayed (> 12 weeks) primary multiligament posterior cruciate ligament (PCL) reconstruction (PCL-R).

METHODS

This study was a retrospective chart review of patients undergoing primary multiligament PCL-R at a single institution between 2008 and 2020. Multiligament PCL-R was defined as PCL-R and concurrent surgical treatment of one or more additional knee ligament(s). Exclusion criteria included isolated PCL-R, PCL repair, and missing data for any variable. Patients were dichotomized into early (≤ 12 weeks) and delayed (> 12 weeks) PCL-R groups based on the time elapsed between injury and surgery. Between-group comparison of variables were conducted with the Chi-square, Fisher's exact, and independent samples t-tests.

RESULTS

A total of 148 patients were eligible for analysis, with 57 (38.5%) patients in the early and 91 (61.1%) patients in the delayed multiligament PCL-R groups. Concomitant LCL/PLC reconstruction (LCL-R/PLC-R) was performed in 55 (60%) of delayed multiligament PCL-Rs and 23 (40%) of early PCL-Rs (p = 0.02). Despite similar rates of meniscus injury, concomitant meniscus surgery was significantly more prevalent in the early (n = 25, 44%) versus delayed (n = 19, 21%) multiligament PCL-R group (p = 0.003), with a significantly greater proportion of medial meniscus surgeries performed in the early (n = 16, 28%) compared to delayed (n = 13, 14%) PCL-R group (p = 0.04). The prevalence of knee cartilage injury was significantly different between the early (n = 12, 24%) and delayed (n = 41, 46%) multiligament PCL-R groups (p = 0.01), with more frequent involvement of the lateral (n = 17, 19% vs. n = 3, 5%, respectively; p = 0.04) and medial (n = 31, 34% vs. n = 6, 11%, respectively; p = 0.005) femoral condyles in the delayed compared to the early PCL-R group.

CONCLUSIONS

Given higher rates of chondral pathology and medial meniscus surgery seen in delayed multiligament PCL-R, early management of PCL-based multiligament knee injury is recommended to restore knee stability and potentially prevent the development of further intraarticular injury.

LEVEL OF EVIDENCE

Level III.

Clinical Effect of Isolated Lateral Closing Wedge Distal Femoral Osteotomy Compared to Medial Opening Wedge High Tibial Osteotomy for the Correction of Varus Malalignment: A Propensity Score-Matched Analysis

BACKGROUND

Recent evidence questions the role of medial opening wedge high tibial osteotomy (mowHTO) in the correction of femoral-based varus malalignment because of the potential creation of an oblique knee joint line. However, the clinical effectiveness of alternatively performing an isolated lateral closing wedge distal femoral osteotomy (lcwDFO), in which the mechanical unloading effect in knee flexion may be limited, is yet to be confirmed.

PURPOSE/HYPOTHESIS

The purpose of this article was to compare clinical outcomes between patients undergoing varus correction via isolated lcwDFO or mowHTO, performed according to the location of the deformity, in a cohort matched for confounding variables. It was hypothesized that results from undergoing isolated lcwDFO for symptomatic varus malalignment would not significantly differ from the results after mowHTO.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Consecutive patients who underwent isolated mowHTO or lcwDFO according to a tibial- or femoral-based symptomatic varus deformity between January 2010 and October 2019 were enrolled. Confounding factors, including age at surgery, sex, body mass index, preoperative femorotibial axis, and postoperative follow-up, were matched using propensity score matching. The International Knee Documentation Committee (IKDC) Subjective Knee Form, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lysholm score, Tegner Activity Scale, and visual analog scale (VAS) for pain were collected preoperatively and at a minimum of 24 months postoperatively.

RESULTS

Of 535 knees assessed for eligibility, 50 knees (n = 50 patients, n = 25 per group) were selected by propensity score matching. Compared with preoperatively, both the mowHTO group (IKDC, 55.1 ± 16.5 vs 71.3 ± 14.7, P = .002; WOMAC, 22.0 ± 18.0 vs 9.6 ± 10.8, P < .001; Lysholm, 55.2 ± 23.1 vs 80.7 ± 16, P < .001; VAS, 4.1 ± 2.4 vs 1.6 ± 1.8, P < .001) and the lcwDFO group (IKDC, 49.4 ± 14.6 vs 66 ± 20.1, P = .003; WOMAC, 25.2 ± 17.0 vs 12.9 ± 17.6, P = .003; Lysholm, 46.5 ± 15.6 vs 65.4 ± 28.7, P = .011; VAS, 4.5 ± 2.2 vs 2.6 ± 2.5, P = .001) had significantly improved at follow-up (80 ± 20 vs 81 ± 43 months). There were no significant differences between the groups at baseline, at final follow-up, or in the amount of clinical improvement in any of the outcome parameters (P > .05; respectively).

CONCLUSION

Performing both mowHTO or lcwDFO yields significant improvement in clinical outcomes if performed at the location of the deformity of varus malalignment. These findings confirm the clinical effectiveness of performing an isolated lcwDFO in femoral-based varus malalignment, which is comparable with that of mowHTO in the correction of varus malalignment.

Closing-Wedge Posterior Tibial Slope-Reducing Osteotomy in Complex Revision ACL Reconstruction

Background

A posterior tibial slope (PTS) >12° has been shown to correlate with failure of anterior cruciate ligament (ACL) reconstruction (ACLR). PTS-reducing osteotomy has been described to correct the PTS in patients with a deficient ACL, mostly after failure of primary ACLR.

Purpose

To report radiologic indices, clinical outcomes, and postoperative complications after PTS-reducing osteotomy performed concurrently with revision ACLR (R-ACLR).

Study Design

Case series; Level of evidence, 4.

Methods

A review of medical records at 3 institutions was performed of patients who had undergone PTS-reducing osteotomy concurrently with R-ACLR between August 2010 and October 2020. Radiologic parameters recorded included the PTS, patellar height according to the Caton-Deschamps Index (CDI), and anterior tibial translation (ATT). Patient-reported outcomes (International Knee Documentation Committee [IKDC] and Knee injury and Osteoarthritis Outcome Score [KOOS]), reoperations, and complications were evaluated.

Results

Included were 23 patients with a mean follow-up of 26.7 months (range, 6-84 months; median, 22.5 months). Statistically significant differences from preoperative to postoperative values were found in PTS (median [range], 14.0° [12°-18°] vs 4.0° [0°-15°], respectively; P < .001), CDI (median, 1.00 vs 1.10, respectively; P = .04) and ATT (median, 8.5 vs 3.6 mm, respectively; P = .001). At the final follow-up, the IKDC score was 52.4 ± 19.2 and the KOOS subscale scores were 81.5 ± 9.5 (Pain), 74 ± 21.6 (Symptoms), 88.5 ± 8 (Activities of Daily Living); 52.5 ± 21.6 (Sport and Recreation), and 48.8 ± 15.8 (Quality of Life). A traumatic ACL graft failure occurred in 2 patients (8.7%). Reoperations were necessary for 6 patients (26.1%) because of symptomatic hardware, and atraumatic recurrent knee instability was diagnosed in 1 patient (4.3%).

Conclusion

Tibial slope-reducing osteotomy resulted in a significant decrease of ATT and can be considered in patients with a preoperative PTS ≥12° and ≥1 ACLR failure. In highly complex patients with multiple prior surgeries, the authors found a reasonably low graft failure rate (8.7%) when utilizing PTS-reducing osteotomy. Surgeons must be aware of potential complications in patients with multiple previous failed ACLRs.

The 50 most cited studies on posterior tibial slope in joint preserving knee surgery

PURPOSE

To determine the 50 most cited studies on posterior tibial slope (PTS) in joint preserving knee surgery and assess their level of evidence, objective study quality scores as well as to examine whether the study quality correlated with the citation count and citation density in the top 50 list.

METHODS

A literature search on Web of Science was performed to determine the 50 most cited studies on the topic of PTS in joint preserving knee surgery between 1990 and 2022. The studies were evaluated for their bibliographic parameters, level of evidence rating (LOE), citation counts, the Modified Coleman Methodological Score (MCMS), the Methodological Index for Non-Randomized Studies (MINORS), and the Radiologic Methodology and Quality Scale (MQCSRE).

RESULTS

Of the top 50 list, 16 studies were published in the American Journal of Sports Medicine. A total of 23 studies were produced in the United States (46%). Of 10 different study types, case control studies (n = 16, 32%) and cadaveric studies (n = 10, 20%) were most common. 15 studies (30%) were purely radiological studies. 6 studies were level II (12%), 23 level III (46%), 15 level IV (30%), and 6 level V studies (12%), respectively. The number of citations ranged from 42 to 447 (mean 105.6 ± 79.2 citations) and showed a mean citation density of 10.3 ± 5.2, composed of the decades 1994 - 2000 (8.3 ± 4.1), 2001 - 2010 (11.1 ± 5.9), 2011 - 2019 (10.1 ± 5.1). Mean quality scores were 55.9 ± 13.0 for MCMS (n = 18), 14.5 ± 3.2 for MINORS (n = 18) and 18.1 ± 3.7 for MQCSRE (n = 20), respectively. High citation counts did not correlate with higher study quality scores (p > 0.05). Radiological studies were not significantly cited more often than non-radiological studies (mean 116.9 ± 88.3 vs. 100.8 ± 75.8 citations; p > 0.05).

CONCLUSION

In joint preserving knee surgery, the 50 most cited studies on PTS did not represent a ranking of the highest methodological quality scores. Citation counts and citation density over the past three decades did not significantly differ, even though the number of articles in the presented list multiplied over the same period. This list can serve as a reference tool for orthopedic surgeons aiming to review PTS literature.

Reliable ligamentous stability and high return-to-sport rates after arthroscopic reduction and internal fixation of tibial eminence fractures

PURPOSE

To investigate functional and clinical outcomes, and physical activity after arthroscopic suture fixation of tibial eminence fractures with regard to postoperative stability, range of motion (ROM), complications, and return to sports.

METHODS

Patients undergoing arthroscopic reduction and internal fixation (ARIF) of tibial eminence fractures using a suture fixation technique were included. Outcome was evaluated retrospectively after a minimum follow-up of 24 months using KT-1000 arthrometer measurements, clinical examination, outcome scores (Lysholm score, Tegner Activity Scale), and a questionnaire about sport activities.

RESULTS

A total of 23 patients (44% male, 57% female) with a mean age of 25 ± 15 years were included. Mean follow-up was 57 ± 25 months. KT-1000 arthrometer measurements of anterior tibial translation revealed a mean side-to-side difference of 0.9 ± 1.0 mm. Clinical examination showed 100% normal or nearly normal anterior translation of the tibia. Two patients (9%) received an ACL reconstruction due to traumatic ACL re-instability and were, therefore, considered as failures. An extension deficit concerning hyperextension occurred in 29% of patients postoperatively. Further postoperative complications occurred in 14% of patients and included postoperative stiffness with ROM limitations and secondary dislocation of a fragment. Mean postoperative Lysholm score was 89 ± 14. Comparing pre- and postoperative values, no significant change of the Tegner Activity Scale was observed. All patients (failures excluded) returned to high impact sports activities after ARIF.

CONCLUSION

Excellent reliable ligamentous stability and high rates of return to high impact sports can be expected after ARIF using a suture fixation technique for type II-IV tibial eminence fractures. Complications, such as limitations in ROM, commonly occur in up to 30% after ARIF. Therefore, regular follow-up examinations remain important in this usually young patient cohort.

LEVEL OF EVIDENCE

Level IV.

Preoperative quantitative pivot shift does not correlate with in vivo kinematics following ACL reconstruction with or without lateral extraarticular tenodesis

PURPOSE

Quantitative pivot shift (QPS) testing using PIVOT technology can detect high- and low-grade rotatory knee instability following anterior cruciate ligament injury or reconstruction (ACLR). The aim of this project was to determine if preoperative QPS correlates with postoperative knee kinematics in the operative and contralateral, healthy extremity following ACLR with or without lateral extraarticular tenodesis (LET) using a highly precise in vivo analysis system. A positive correlation between preoperative QPS and postoperative tibial translation and rotation following ACLR with or without LET in the operative and healthy, contralateral extremity was hypothesized.

METHODS

Twenty patients with ACL injury and high-grade rotatory knee instability were randomized to undergo anatomic ACLR with or without LET as part of a prospective randomized trial. At 6 and 12 months postoperatively, in vivo kinematic data were collected using dynamic biplanar radiography superimposed with high-resolution computed tomography scans of patients' knees during downhill running. Total anterior-posterior (AP) tibial translation and internal-external tibial rotation were measured during the gait cycle. Spearman's rho was calculated for preoperative QPS and postoperative kinematics.

RESULTS

In the contralateral, healthy extremity, a significant positive correlation was seen between preoperative QPS and total AP tibial translation at 12 months postoperatively (r_s = 0.6, p < 0.05). There were no additional significant correlations observed between preoperative QPS and postoperative knee kinematics at 6 and 12 months postoperatively in the operative and contralateral, healthy extremity for combined isolated ACLR and ACLR with LET patients as well as isolated ACLR patients or ACLR with LET patients analyzed separately.

DISCUSSION

The main finding of this study was that there was a significant positive correlation between preoperative QPS and total AP tibial translation at 12 months postoperatively in the contralateral, healthy extremity. There were no significant correlations between preoperative QPS and postoperative in vivo kinematics at 6 and 12 months following ACLR with or without LET. This suggests that QPS as measured with PIVOT technology does correlate with healthy in vivo knee kinematics, but QPS does not correlate with in vivo kinematics following ACLR with or without LET.

Favorable long-term clinical and radiologic outcomes with high survivorship after autologous osteochondral transplantation of the talus

PURPOSE

To evaluate long-term clinical and radiologic outcomes of patients undergoing autologous osteochondral transplantation (AOT) for osteochondral lesions of the talus (OLT) and to perform a correlation analysis between clinical and radiologic outcomes.

METHODS

Thirty-five patients with a mean age of 32.2 ± 8.9 years undergoing AOT for OLT between 1997 and 2003 were available for follow-up after an average of 19.1 ± 1.4 years. Demographic, surgical, and injury-related data were collected. After a minimum 18-year follow-up, patient-reported outcome scores (PROs) were collected, including the American Orthopaedic Foot & Ankle Society (AOFAS) score, the Foot and Ankle Outcome Score (FAOS), Tegner Activity Scale, and Visual Analogue Scale (VAS) for pain of the ankle. The Lysholm Score and VAS for pain of the knee were collected to assess donor-site morbidity. Magnetic resonance imaging scans were obtained to conduct an assessment of the replaced cartilage using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) 2.0 scoring system. Any revision surgery (except symptomatic hardware removal and arthroscopic debridement) was defined as clinical failure.

RESULTS

Favorable clinical and radiologic (MOCART score, 73.7 ± 16.7 points) outcomes without any donor-site morbidities were observed. Twenty-three (65.7%) patients were satisfied or very satisfied with the surgical treatment. Fourteen (40.0%) and 25 (71.4%) patients had no or minor limitations in their athletic and working performance, respectively. A significant correlation between the MOCART and the FAOS Sport and Recreational activities subscale was found (r_s, 0.491; p = 0.033). Six (17.1%) patients met the criteria for clinical failure an average of 12.2 ± 6.6 years after AOT. Survival analysis demonstrated a mean estimated time of survival of 21.3 years (95% CI [19.55, 22.96]) and a 20-year survival rate of 77.9%.

CONCLUSION

Autologous osteochondral transplantation to treat OLT achieves high patient satisfaction and favorable PROs with a 20-year survival rate of almost 80%. Given the high clinical efficacy of AOT, this procedure can be recommended as a safe and promising technique for the long-term therapy of OLT.

LEVEL OF EVIDENCE

Level IV.

Increasing the posterior tibial slope lowers in situ forces in the native ACL primarily at deep flexion angles

High tibial osteotomy is becoming increasingly popular but can be associated with unintentional posterior tibial slope (PTS) increase and subsequent anterior cruciate ligament (ACL) degeneration. This study quantified the effect of increasing PTS on knee kinematics and in situ forces in the native ACL. A robotic testing system was used to apply external loads from full extension to 90° flexion to seven human cadaveric knees: (1) 200 N axial compressive load, (2) 5 Nm internal tibial + 10 Nm valgus torque, and (3) 5 Nm external tibial + 10 Nm varus torque. Kinematics and in situ forces in the ACL were acquired for the native and increased PTS state. Increasing PTS resulted in increased anterior tibial translation at 30° (1.8 mm), 60° (1.7 mm), and 90° (0.9 mm) flexion and reduced in situ force in the ACL at 30° (57.6%), 60° (69.8%), and 90° (75.0%) flexion in response to 200 N axial compressive load. In response to 5 Nm internal tibial + 10 Nm valgus torque, there was significantly less (39.0%) in situ force in the ACL at 90° flexion in the increased compared with the native PTS state. Significantly less in situ force in the ACL at 60° (62.8%) and 90° (67.0%) flexion was observed in the increased compared with the native PTS state in response to 5 Nm external tibial + 10 Nm varus torque. Increasing PTS affects knee kinematics and results in a reduction of in situ forces in the native ACL during compressive and rotatory loads at flexion angles exceeding 30°. In a controlled laboratory setting PTS increase unloads the ACL, affecting its natural function.

Player Position and Labral Tear Location and Size in NCAA Division I Football Players Undergoing Arthroscopic Surgery

Background:

Shoulder instability attributed to glenoid labral tears is common among National Collegiate Athletic Association (NCAA) football players. Certain repetitive activities by player position may contribute to instability.

Purpose:

To compare the location of labral tears among player positions in NCAA Division I football.

Study Design:

Cross-sectional study.

Methods:

We conducted a review of football players who underwent shoulder labral repair between 2000 and 2020 at a single institution. Inclusion criteria were NCAA Division I level, diagnosis of shoulder instability, and labral tear requiring arthroscopic repair. Exclusion criteria were prior surgery on injured shoulder and incomplete medical records. Players were divided into 3 groups: line players (offensive and defensive linemen, defensive end), skill players (defensive back, wide receiver, running back, and quarterback), and hybrid players (linebacker and tight end). Labral tear location and size were recorded using the clockface method and categorized into 6 zones: superior, anterosuperior, anteroinferior, inferior, posteroinferior, and posterosuperior. Comparison of variables was performed using chi-square test or Fisher exact test (categorical) and 1-way analysis of variance or Kruskal-Wallis H test (continuous). The Spearman rank-order correlation was used to assess relationships between continuous data.

Results:

Of the 53 included players, 37 (70%) were offensive linemen, defensive linemen, and linebackers. There were 29 line players, 11 skill players, and 13 hybrid players. Line players represented 55% of included players and had the most total labral tears as compared with all groups. Hybrid players had a significantly higher percentage of posterosuperior tears than line players (92% vs 52%; P = .015) and skill players (92% vs 27%; P = .002). Skill players had a significantly higher percentage of anterior tears at 3:00-4:00 and 5:00-6:00 when compared with hybrid players (82% vs 15%, P = .003; 82% vs 31%, P = .012, respectively). There was a positive correlation between labral tear size and number of suture anchors (0; P = .010).

Conclusion:

In this study of NCAA Division I football players, skill players had a higher proportion of anteroinferior labral tears, and hybrid players had a higher proportion of posterosuperior labral tears.

Ultrasound-Guided Anterior Talofibular Ligament Repair With Augmentation Can Restore Ankle Kinematics: A Cadaveric Biomechanical Study

Background:

Anterior talofibular ligament (ATFL) repair of the ankle is a common surgical procedure. Ultrasound (US)-guided anchor placement for ATFL repair can be performed anatomically and accurately. However, to our knowledge, no study has investigated ankle kinematics after US-guided ATFL repair.

Hypothesis:

US-guided ATFL repair with and without inferior extensor retinaculum (IER) augmentation will restore ankle kinematics.

Study Design:

Controlled laboratory study; Level of evidence, 4.

Methods:

A 6 degrees of freedom robotic testing system was used to apply multidirectional loads to fresh-frozen cadaveric ankles (N = 9). The following ankle states were evaluated: ATFL intact, ATFL deficient, combined ATFL repair and IER augmentation, and isolated US-guided ATFL repair. Three loading conditions (internal-external rotation torque, anterior-posterior load, and inversion-eversion torque) were applied at 4 ankle positions: 30° of plantarflexion, 15° of plantarflexion, 0° of plantarflexion, and 15° of dorsiflexion. The resulting kinematics were recorded and compared using a 1-way repeated-measures analysis of variance with the Benjamini-Hochberg test.

Results:

Anterior translation in response to an internal rotation torque significantly increased in the ATFL-deficient state compared with the ATFL-intact state at 30° and 15° of plantarflexion (P = .022 and .03, respectively). After the combined US-guided ATFL repair and augmentation, anterior translation was reduced significantly compared with the ATFL-deficient state at 30° and 15° of plantarflexion (P = .0012 and .005, respectively). Anterior translation was not significantly different for the isolated ATFL-repair state compared with the ATFL-deficient or ATFL-intact states at 30° and 15° of plantarflexion.

Conclusion:

Combined US-guided ATFL repair with augmentation of the IER reduced lateral ankle laxity due to ATFL deficiency. Isolated US-guided ATFL repair did not reduce laxity due to ATFL deficiency, nor did it increase instability compared with the intact ankle.

Clinical Relevance:

US-guided ATFL repair with IER augmentation is a minimally-invasive technique to reduce lateral ankle laxity due to ATFL deficiency. Isolated US-guided ATFL repair may be a viable option if accompanied by a period of immobilization.

Practice Patterns for Revision Anterior Cruciate Ligament Reconstruction in an Integrated Health Care System

Background

While surgeons with high caseload volumes deliver higher value care when performing primary anterior cruciate ligament reconstruction (ACLR), the effect of surgeon volume in the revision setting is unknown.

Purposes

To determine the percentage of revision ACLR procedures that comprise the practice of high-, medium-, and low-volume surgeons and to analyze associated referral and practice patterns.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

We retrospectively investigated all revision ACLR procedures performed between 2015 and 2020 in a single health care system. Surgeons were categorized as low (≤17), medium (18-34), or high (≥35) volume based on the number of annual ACLR procedures performed. Patient characteristics, activity level, referral source, concomitant injuries, graft type, and treatment variables were recorded, and a comparison among surgeon groups was performed.

Results

Of 4555 ACLR procedures performed during the study period, 171 (4%) were revisions. The percentage of revision ACLR procedures was significantly higher for high-volume (5%) and medium-volume (4%) surgeons compared with low-volume surgeons (2%) (P < .01). Patients undergoing revision ACLR by a high-volume surgeon had a significantly higher baseline activity level (P = .01). Allografts were used significantly more often by low-volume surgeons (70%) compared with medium-volume (35%) and high-volume (25%) surgeons (P < .01). Bone-patellar tendon-bone (BPTB) and quadriceps tendon (QT) autografts were used significantly more often by high-volume (32% BPTB, 39% QT) and medium-volume (38% BPTB, 14% QT) surgeons compared with low-volume surgeons (15% BPTB, 10% QT) (P < .01). High-volume surgeons were more likely to perform revision on patients with cartilage injuries (P = .01), perform staged revision ACLR (P = .01), and choose meniscal repair (54% high vs 22% medium and 36% low volume; P = .03), despite similar rates of concomitant meniscal tears, compared with low- and medium-volume surgeons.

Conclusion

In this registry study of an integrated health care system, high-volume surgeons were more likely to perform revision ACLR on patients with higher activity and competition levels. Additionally, high-volume surgeons more commonly performed staged revision ACLR, chose meniscus-sparing surgery, and favored the use of autografts compared with low-volume surgeons.

Improved Clinical Outcome and High Rate of Return to Low-Impact Sport and Work After Knee Double Level Osteotomy for Bifocal Varus Malalignment

PURPOSE

To evaluate return to sport (RTS) and work (RTW), as well as clinical outcomes following double level osteotomy (DLO) via combined medial open wedge high tibial osteotomy and lateral closing wedge distal femoral osteotomy for bifocal symptomatic varus malalignment, and to compare these outcome parameters between patients undergoing a single surgery and those undergoing a two-stage procedure.

METHODS

Consecutive patients who underwent DLO for symptomatic varus malalignment between 12/2007 and 03/2018 were enrolled. Patients converted to arthroplasty (n = 3) during follow-up were excluded. Outcome measures included the International Knee Documentation Committee (IKDC) Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lysholm score, Tegner Activity Scale, and visual analog scale (VAS) for pain, which were collected preoperatively and at a minimum of 24 months postoperatively. RTS and RTW were evaluated by questionnaire. Outcome measures were compared between DLO performed in a single- versus a two-stage surgery.

RESULTS

Thirty-two patients (mean age: 44.2 ± 12.6 years), who underwent DLO for varus malalignment (10.1° ± 2.9°) were included at a mean follow-up of 56.9 ± 35.3 months (range: 24-148). Compared to preoperatively, these patients significantly improved in IKDC (50.4 ± 13.9 to 66.1 ± 15.4; P < .001), WOMAC (29.7 ± 19.2 to 11.8 ± 13.5; P < .001) and Lysholm (53.6 ± 23.6 to 73.1 ± 23.6; P = .002) scores at final follow-up. For the WOMAC score, 78% of the patients included reached the minimally important clinical difference, along with a significant reduction of the VAS for pain (5.0 ± 3.0 to 2.5 ± 2.4; P < .001). Postoperatively, 96% of patients returned to sport after 7.7 ± 4.8 months, but at a lower frequency (P = .010) and to fewer disciplines (P = .005) with a shift to low-impact sports. 90% of the patients returned to work at a mean 5.9 ± 9.4 months, with 79% reporting a similar or superior working ability. Patients undergoing a two-stage procedure recovered to full physical working ability at a significantly longer duration, as compared to a single-stage procedure (9.8 ± 3.8 vs 9.0 ± 13.1 months; P = .047).

CONCLUSION

The majority of patients undergoing DLO for symptomatic varus malalignment, who were not converted to arthroplasty, experienced clinically significant functional improvement at mid-term follow-up. Return to sport and work rates in these patients were high; however, a shift to lower-impact sports disciplines was observed. Similar clinical outcomes can be expected when performing DLO in a single surgery or a two-stage procedure.

LEVEL OF EVIDENCE

Retrospective case series; Level IV.

Transpatellar bone tunnels perforating the lateral or anterior cortex increase the risk of patellar fracture in MPFL reconstruction: a finite element analysis and survey of the International Patellofemoral Study Group

PURPOSE

(1) To determine applied patellar drilling techniques for medial patellofemoral ligament (MPFL) reconstruction among members of the International Patellofemoral Study Group (IPSG) and (2) to evaluate the risk of patellar fracture for various patellar bone tunnel locations based on a finite element analysis (FEA) model.

METHODS

In the first part of the study, an online survey on current MPFL reconstruction techniques was conducted among members of the IPSG. In the second part of the study, a three-dimensional FEA model of a healthy knee joint was created using a computed tomography scan. Patient-specific bone density was integrated into the patella, and cartilage of 3 mm thickness was modeled for the patellofemoral joint. According to the survey's results, two different types of patellar bone tunnels (bone socket and transpatellar bone tunnel) were simulated. The risk of patellar fracture was evaluated based on the fracture risk volume (FRV) obtained from the FEA.

RESULTS

Finite element analysis revealed that subchondral bone socket tunnel placement is associated with the lowest FRV but increased with an anterior offset (1-5 mm). Transpatellar bone tunnels violating the lateral or anterior cortex showed a higher FRV compared to bone socket, with the highest values observed when the anterior cortex was penetrated.

CONCLUSION

Violation of the anterior or lateral patellar cortex using transpatellar bone tunnels increased FRV compared to a subchondral patellar bone socket tunnel. In MPFL reconstruction, subchondral patellar bone socket tunnels should be considered for patellar graft fixation to avoid the risk of postoperative patellar fracture.

LEVEL OF EVIDENCE

Survey; Descriptive laboratory study/Level V.

Different injury patterns exist among patients undergoing operative treatment of isolated PCL, combined PCL/ACL, and isolated ACL injuries: a study from the Swedish National Knee Ligament Registry

PURPOSE

To compare demographic characteristics and concomitant injury patterns in patients undergoing primary isolated posterior cruciate ligament reconstruction (PCL-R) and combined posterior cruciate ligament (PCL) and anterior cruciate ligament (ACL) reconstruction (PCL-R/ACL-R) with isolated ACL reconstruction (ACL-R) as a reference using data from the Swedish National Knee Ligament Registry (SNKLR).

METHODS

This cohort study based on the SNKLR comprised patients undergoing either PCL-R, ACL-R, or combined PCL-R/ACL-R between January 1, 2005 and December 31, 2019 in Sweden. Demographic and surgery-related data with regards to injury mechanism, concomitant intraarticular lesions and their treatment, neurovascular damage, and concomitant ligamentous injuries were extracted. Exclusion criteria included concomitant fractures of the femur, fibula, patella or tibia, and quadriceps or patellar tendon injury.

RESULTS

A total of 45,564 patients were included in this study. Isolated PCL-R, combined PCL-R/ACL-R, and isolated ACL-R were performed in 192 (0.4%), 203 (0.5%) and 45,169 (99.1%) patients, respectively. Sports were identified as the cause of 64% of PCL-Rs, 54% of PCL-R/ACL-Rs, and 89% of ACL-Rs, while a traffic-related mechanism was identified in 20% of PCL-Rs, 27% of PCL-R/ACL-Rs and 2% of ACL-Rs. Meniscus injury prevalence was 45% in ACL-Rs, 31% in PCL-R/ACL-Rs and 16% in isolated PCL-Rs (p < 0.001). Cartilage injuries were more common in PCL-R (37%) and PCL-R/ACL-R patients (40%) compared to ACL-R patients (26%, p < 0.001). Concomitant knee ligament injury was identified in 28-44% of PCL-R/ACL-R patients. Neurovascular injuries were present in 9% of PCL-R/ACL-Rs, 1% of PCL-Rs, and 0.3% of ACL-Rs (p < 0.001).

CONCLUSION

Differences in injury mechanisms among patient groups confirm that operatively treated PCL tears are frequently caused by both traffic and sports. Cartilage and ligament injuries were more frequent in patients with PCL-R compared to ACL-R. Consequently, combined PCL and ACL tears should raise suspicion for concomitant knee lesions with clinical relevance during the operative treatment of these complex injuries.

LEVEL OF EVIDENCE

III.

A high tibial slope, allograft use, and poor patient-reported outcome scores are associated with multiple ACL graft failures

PURPOSE

To compare clinical outcomes, radiographic characteristics, and surgical factors between patients with single and multiple anterior cruciate ligament (ACL) graft failures. It was hypothesized that patients experiencing multiple ACL graft failures exhibit lower patient-reported outcome scores (PROs) and a higher (steeper) posterior tibial slope (PTS) than patients with single ACL graft failure.

METHODS

Patients undergoing revision ACL reconstruction with a minimum follow-up of 12 months were included in this retrospective cohort study. Based on the number of ACL graft failures, patients were assigned either to the group "single ACL graft failure "or" multiple ACL graft failures ". The PTS was measured on strict lateral radiographs. Validated PROs including the International Knee Documentation Committee (IKDC) subjective knee form, Knee Injury and Osteoarthritis Outcome Score, Lysholm Score, Tegner Activity Scale, ACL-Return to Sport after Injury Scale, and Visual Analogue Scale for pain were collected.

RESULTS

Overall, 102 patients were included with 58 patients assigned to the single ACL graft failure group and 44 patients to the multiple ACL graft failures group. Quadriceps tendon autograft was used significantly more often (55% vs. 11%, p < 0.001) and allografts were used significantly less often (31% vs. 66%, p < 0.001) as the graft for first revision ACL reconstruction in patients with single versus multiple ACL graft failures. Patients with multiple ACL graft failures were associated with statistically significantly worse PROs (IKDC: 61.7 ± 19.3 vs. 77.4 ± 16.8, p < 0.05; Tegner Activity Scale: 4 (range, 0-7) vs. 6 (range 2-10), p < 0.05), higher PTS (12 ± 3° vs. 9 ± 3°, p < 0.001), and higher rates of subsequent surgery (73% vs. 14%, p < 0.001) and complications (45% vs. 17%, p < 0.05) than patients with single ACL graft failure.

CONCLUSION

Compared to single ACL graft failure in this study multiple ACL graft failures were associated with worse PROs, higher PTS, and allograft use. During the first revision ACL reconstruction, it is recommended to avoid the use of allografts and to consider slope-reducing osteotomies to avoid multiple ACL graft failures and improve PROs.

LEVEL OF EVIDENCE

Level 3.

High return to sports and return to work rates after anatomic lateral ankle ligament reconstruction with tendon autograft for isolated chronic lateral ankle instability

PURPOSE

To evaluate clinical outcomes as well as return to sports (RTS) and return to work (RTW) rates following anatomic lateral ankle ligament reconstruction with a tendon autograft for chronic lateral ankle instability (CLAI) in a high-risk population, and to compare these outcome parameters between patients having received a gracilis tendon autograft (GT) and free split peroneus brevis tendon (PBT) autograft.

METHODS

Twenty-eight consecutive patients, who were diagnosed with CLAI, presenting with ≥ 1 risk factor (ligamentous hyperlaxity, insufficient substance of native ligament and/or high-demand athlete), who underwent ankle ligament reconstruction with a tendon autograft between January 2011 and December 2018, were included in this retrospective study. At 63.7 ± 28.0 months (24-112), 23 patients with a mean age of 29.7 ± 10.9 years were available for follow-up. The Karlsson Score, the Foot and Ankle Outcome Score (FAOS), the Tegner Activity Scale and the visual analog scale (VAS) for pain were collected at a minimum follow-up of 24 months. RTS and RTW were evaluated by questionnaire. A subgroup analysis with regard to the graft used for ankle ligament reconstruction (GT versus PBT) was performed.

RESULTS

Patients reported a Karlsson score of 82.1 ± 17.5 (37-100), a FAOS score of 87.8 ± 8.4 (73-99), a median Tegner activity scale of 5.0 (IQR 4-6) and a VAS for pain of 0.5 ± 0.9 (0-4) at rest and of 2.0 ± 2.1 (0-7) during activities at final follow-up. Postoperatively, 96% of patients had returned to sports after 8.3 ± 6.2 months. All patients (100%) had returned to work at 3.5 ± 5.7 (0-24) months, with 87% reporting an equal or improved working ability compared to that preoperatively. Postoperatively, exercise hours per week were significantly reduced compared to preoperatively in patients with a split PBT (n = 12; 13.0 ± 12.9 to 5.6 ± 6.4 h, p = 0.038) autograft as opposed to patients with a GT autograft (n = 11; 13.1 ± 8.7 to 12.4 ± 7.1 h, n.s.). No other group differences were observed.

CONCLUSION

Good patient-reported outcomes as well as excellent RTS and RTW rates can be achieved in high-risk patients undergoing ankle ligament reconstruction with a tendon autograft for CLAI. These results may be helpful in preoperatively managing patients' expectations regarding sports- and work-related outcomes and provide tangible data on the expectable time frame of the individual return to sports and work trajectory.

LEVEL OF EVIDENCE

IV.

Quadriceps tendon autograft is becoming increasingly popular in revision ACL reconstruction

PURPOSE

To evaluate trends in revision anterior cruciate ligament reconstruction (ACL-R), with emphasis on intra-articular findings, grafts, and concurrent procedures. It was hypothesized that revision ACL-Rs over time show a trend toward increased complexity with increased use of autografts over allografts.

METHODS

This was a two-center retrospective study including patients undergoing revision ACL-R between 2010 and 2020. Demographic and surgical data including intra-articular findings and concurrent procedures were collected and compared for the time periods 2010-2014 and 2015-2020. All collected variables were compared between three pre-defined age groups (< 20 years, 20-30 years, > 30 years), right and left knees, and males and females. A time series analysis was performed to assess trends in revision ACL-R.

RESULTS

This study included 260 patients with a mean age of 26.2 ± 9.4 years at the time of the most recent revision ACL-R, representing the first, second, third, and fourth revision ACL-R for 214 (82%), 35 (14%), 10 (4%), and 1 (< 1%) patients, respectively. Patients age > 30 years showed a significantly longer mean time from primary ACL-R to most recent revision ACL-R (11.1 years), compared to patients age < 20 years (2.2 years, p < 0.001) and age 20-30 years (5.5 years, p < 0.05). Quadriceps tendon autograft was used significantly more often in 2015-2020 compared to 2010-2014 (49% vs. 18%, p < 0.001). A high rate of concurrently performed procedures including meniscal repairs (45%), lateral extra-articular tenodesis (LET; 31%), osteotomies (13%), and meniscal allograft transplantations (11%) was shown. Concurrent LET was associated with intact cartilage and severely abnormal preoperative knee laxity and showed a statistically significant and linear increase over time (p < 0.05). Intact cartilage (41%, p < 0.05), concurrent medial meniscal repairs (39%, p < 0.05), and LET (35%, non-significant) were most frequently observed in patients aged < 20 years.

CONCLUSION

Quadriceps tendon autograft and concurrent LET are becoming increasingly popular in revision ACL-R. Intact cartilage and severely abnormal preoperative knee laxity represent indications for LET in revision ACL-R. The high rate of concurrent procedures observed demonstrates the high surgical demands of revision ACL-R.

LEVEL OF EVIDENCE

Level III.

Continuous-Loop Tape Technique Has Greater Stiffness and Less Elongation Compared With Tied-Suture Fixation of Full-Thickness All-Soft Tissue Quadriceps Tendon Autografts

Background

Many graft fixation techniques are utilized for full-thickness soft tissue quadriceps tendon autografts during anterior cruciate ligament reconstruction (ACLR).

Purpose

To determine the tensile properties of all-soft tissue quadriceps tendon graft fixation using a tied-suture versus continuous-loop tape technique. It was hypothesized that the continuous-loop tape technique would have less cyclic elongation and greater ultimate load to failure and stiffness compared with a commonly used tied-suture technique.

Study Design

Controlled laboratory study.

Methods

Sixteen fresh-frozen human knee specimens were used to harvest a full-thickness all-soft tissue quadriceps tendon graft; half were secured using a Krackow suture technique with 2 braided sutures, and half were secured using a continuous-loop tape suspensory fixation button with a rip-stop stitch. Cyclic and permanent elongation, toe- and linear-region stiffness, and ultimate load were determined. Statistical analysis was performed at P <.05.

Results

The tied-suture fixation group demonstrated significantly higher permanent elongation (11.7 ± 3.6 vs 4.2 ± 1.0 mm, P < .001) and cyclic elongation (5.9 ± 1.3 vs 2.0 ± 0.4 mm, P < .001) compared with the continuous-loop tape fixation group. There was a significantly higher linear-region stiffness with continuous-loop tape fixation compared with tied-suture fixation (98.8 ± 12.7 vs 85.5 ± 7.5 N/mm, P = .022). No significant difference in ultimate load between groups (517.1 ± 149.2 vs 465.6 ± 64.6 N) was found. The mode of failure was tendon pull-through for the continuous-loop tape group and suture breakage in the tied-suture group (P < .001).

Conclusion

Continuous-loop tape fixation is superior to tied-suture fixation in regard to elongation and stiffness for all-soft tissue quadriceps tendon grafts, but there was no significant difference in ultimate load.

Clinical Relevance

Continuous-loop tape fixation of all-soft tissue quadriceps tendon grafts for ACLR is a valid technique with superior tensile properties.

[Posterior meniscus root tears]

Meniscus root tears are radial tears in the region of the posterior insertion zones. Medial root injuries usually occur in individuals > 50 years of age without adequate trauma and are associated with obesity and varus deformities. The root lesion leads to a loss of ring tension, which results in extrusion of the meniscus and a strong increase in joint pressure that is biomechanically equivalent to a complete meniscectomy. When indicating arthroscopic transosseous refixation of the medial root lesion, factors such as accompanying cartilage damage, osteoarthritis, obesity and varus deformity must be taken into account. Injuries to the root of the lateral meniscus are mostly observed in younger patients in combination with a rupture of the anterior cruciate ligament. Arthroscopic transosseous refixation in combination with cruciate ligament surgery is therefore also recommended for type I and type II lesions. In summary, both the medial and the lateral root lesions of the menisci are injuries with high biomechanical relevance.

Combined posterolateral knee reconstruction: ACL-based injuries perform better compared to PCL-based injuries

PURPOSE

To compare post-operative physical activity and return to work after combined posterolateral corner (PLC) reconstruction (PLC-R) in anterior cruciate ligament (ACL)- or posterior cruciate ligament (PCL)-based injuries.

METHODS

Patients aged > 18 years undergoing PLC-R using the Larson technique combined with either ACL or PCL reconstruction were included. Outcome was evaluated retrospectively after a minimum follow-up of 24 months using Tegner Activity Scale, Activity Rating Scale (ARS), Knee Injury and Osteoarthritis Outcome Score (KOOS), work intensity according to REFA classification, and a questionnaire about type of occupation and time to return to work.

RESULTS

A total of 32 patients (11 ACL-based injuries and 21 PCL-based injuries) were included. Mean follow-up was 56 ± 26 months in the ACL-based injury group and 59 ± 24 months in the PCL-based injury group. All patients in the ACL-based injury group and 91% of patients in the PCL-based injury group returned to sports activities. Comparing pre- and post-operative values, a significant deterioration of the Tegner Activity Scale and ARS was observed in the PCL-based injury group, whereas no significant change was observed in the ACL-based injury group. KOOS subscales were generally higher in the ACL-based injury with significant differences in the subscale sports and recreational activities. Patients with ACL-based injuries returned to work significantly earlier compared to patients with PCL-based injuries (11 ± 4 weeks vs. 21 ± 10 weeks, p < 0.05).

CONCLUSION

High rates of return to sports and work can be expected after combined PLC-R in both ACL- and PCL-based injuries. However, deterioration of sports ability must be expected in PCL-based injuries. ACL-based injuries led to superior patient-reported outcomes and an earlier return to work, as compared to PCL-based injuries.

LEVEL OF EVIDENCE

Level IV.

Association Between Meniscal Allograft Tears and Early Surgical Meniscal Allograft Failure

BACKGROUND

Meniscal allograft transplantation (MAT) has become a viable treatment option for patients with symptomatic meniscal deficiency. Some patients experience early surgical meniscal allograft failure attributed to causes that have not yet been sufficiently clarified.

PURPOSE

To evaluate the prevalence, types, and distribution of arthroscopically confirmed meniscal allograft tears and the associated effect on surgical meniscal allograft survival.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing MAT with a minimum 2-year follow-up were retrospectively reviewed. Descriptive and surgical data were collected. Type and location of arthroscopically confirmed meniscal allograft tears were recorded and compared between medial and lateral allografts and suture-only and bone block fixation. A survival analysis was conducted to evaluate the effect of meniscal allograft tears on surgical meniscal allograft survival.

RESULTS

This study included 142 patients (54% male; mean ± SD age, 29.6 ± 10.4 years) with a mean follow-up of 10.3 ± 7.5 years. The prevalence of meniscal allograft tears was 32%, observed at a median of 1.2 years (interquartile range, 2.8 years) after MAT. The posterior horns were most frequently affected, followed by the posterior roots, midbodies, anterior horns, and anterior roots. The most frequently observed tear types were root tears (43%), followed by longitudinal, horizontal, radial, complex, bucket-handle, and meniscocapsular separation tears. A statistically significant association was found between meniscal allograft tear types and fixation techniques (P = .027), with root tears predominant after suture-only as compared with bone block fixation (57% vs 22%). Patients with meniscal allograft root tears were a mean of 5.4 years (95% CI, 1.6-9.2 years; P = .007) younger than were patients without root tears. The 1-year surgical meniscal allograft survival rate was significantly lower for torn versus intact meniscal allografts (75% vs 99%; P < .001).

CONCLUSION

Meniscal allograft root tears were predominant, associated with younger patient age, and more often observed when using the suture-only fixation technique versus the bone block fixation technique. Torn meniscal allografts were associated with early surgical graft failure when compared with intact meniscal allografts, resulting in a significantly lower 1-year survival rate.

Evolving evidence in the treatment of primary and recurrent posterior cruciate ligament injuries, part 2: surgical techniques, outcomes and rehabilitation

Isolated and combined posterior cruciate ligament (PCL) injuries are associated with severe limitations in daily, professional, and sports activities as well as with devastating long-term effects for the knee joint. As the number of primary and recurrent PCL injuries increases, so does the body of literature, with high-quality evidence evolving in recent years. However, the debate about the ideal treatment approach such as; operative vs. non-operative; single-bundle vs. double-bundle reconstruction; transtibial vs. tibial inlay technique, continues. Ultimately, the goal in the treatment of PCL injuries is restoring native knee kinematics and preventing residual posterior and combined rotatory knee laxity through an individualized approach. Certain demographic, anatomical, and surgical risk factors for failures in operative treatment have been identified. Failures after PCL reconstruction are increasing, confronting the treating surgeon with challenges including the need for revision PCL reconstruction. Part 2 of the evidence-based update on the management of primary and recurrent PCL injuries will summarize the outcomes of operative and non-operative treatment including indications, surgical techniques, complications, and risk factors for recurrent PCL deficiency. This paper aims to support surgeons in decision-making for the treatment of PCL injuries by systematically evaluating underlying risk factors, thus preventing postoperative complications and recurrent knee laxity. LEVEL OF EVIDENCE: V.

Evolving evidence in the treatment of primary and recurrent posterior cruciate ligament injuries, part 1: anatomy, biomechanics and diagnostics

The posterior cruciate ligament (PCL) represents an intra-articular structure composed of two distinct bundles. Considering the anterior and posterior meniscofemoral ligaments, a total of four ligamentous fibre bundles of the posterior knee complex act synergistically to restrain posterior and rotatory tibial loads. Injury mechanisms associated with high-energy trauma and accompanying injury patterns may complicate the diagnostic evaluation and accuracy. Therefore, a thorough and systematic diagnostic workup is necessary to assess the severity of the PCL injury and to initiate an appropriate treatment approach. Since structural damage to the PCL occurs in more than one third of trauma patients experiencing acute knee injury with hemarthrosis, background knowledge for management of PCL injuries is important. In Part 1 of the evidence-based update on management of primary and recurrent PCL injuries, the anatomical, biomechanical, and diagnostic principles are presented. This paper aims to convey the anatomical and biomechanical knowledge needed for accurate diagnosis to facilitate subsequent decision-making in the treatment of PCL injuries.Level of evidence V.

Isolated high tibial osteotomy is appropriate in less than two-thirds of varus knees if excessive overcorrection of the medial proximal tibial angle should be avoided

PURPOSE

To perform a detailed deformity analysis of patients with varus alignment and to define the ideal osteotomy level (tibial vs. femoral vs. double level) to avoid an oblique joint line.

METHODS

A total of 303 digital full-leg standing radiographs of patients aged 18-60 years and varus alignment [mechanical tibiofemoral varus angle (mFTA) ≥ 3°] were included. All legs were analyzed regarding mFTA, mechanical medial proximal tibia angle (mMPTA), mechanical lateral distal femur angle (mLDFA), and joint line convergence angle. Based on mFTA, varus alignment was categorized as "mild" (3°-5°), "moderate" (6°-8°), or "severe" (≥ 9°). Deformity location was determined according to the malalignment test described by Paley. Two osteotomy simulations were performed with different upper limits for mMPTA: anatomic correction (mMPTA ≤ 90°, mLDFA ≥ 85°) and overcorrection (mMPTA ≤ 95°, mLDFA ≥ 85°). If a single osteotomy exceeded these limits at the intended mFTA of 2° valgus, a double-level osteotomy was simulated. If even a double-level osteotomy resulted in deviations from the defined limits, the leg was categorized as "uncorrectable".

RESULTS

Mean mFTA was 6° ± 11° of varus (range 3°-15°). A tibial deformity was observed in 28%, a femoral deformity in 23%, a combined tibial and femoral deformity in 4%, and no bony deformity in 45%. The prevalence of a tibial deformity did not differ between varus severity groups, whereas a femoral and bifocal deformity was significantly more prevalent in knees with more distinct varus (p < 0.001). Osteotomy simulation revealed that isolated high tibial osteotomy (HTO) was appropriate in only 12% for anatomic correction, whereas a double-level osteotomy was necessary in 63%. If overcorrection of mMPTA was tolerated, the number of HTOs significantly increased to 57% (p < 0.001), whereas the number of double-level osteotomies significantly decreased to 33% (p < 0.001). Isolated DFO was considered ideal in 8% for both simulations. Significantly more knees were considered "uncorrectable" by simulating anatomic correction (18 vs. 2%; p < 0.001). A double-level osteotomy was significantly more often necessary in knees with "severe" varus (p < 0.001).

CONCLUSION

Less than one-third of patients (28%) with mechanical varus ≥ 3° have a tibial deformity. If anatomic correction (mMPTA ≤ 90°) is intended, only 12% of patients can be corrected via isolated HTO, whereas 63% of patients require a double-level osteotomy. If slight overcorrection is accepted (mMPTA ≤ 95°), 57% of patients can be corrected via isolated HTO, whereas 33% of patients would still require a double-level osteotomy.

LEVEL OF EVIDENCE

III, cross-sectional study.

A hinge position distal to the adductor tubercle minimizes the risk of hinge fractures in lateral open wedge distal femoral osteotomy

PURPOSE

To evaluate the incidence and morphology of medial cortical hinge fractures in lateral open wedge distal femoral osteotomy (LOW-DFO) and to determine a safe zone for the position of the osteotomy hinge to minimize the risk of hinge fractures.

METHODS

Consecutive patients who underwent LOW-DFO for symptomatic valgus malalignment were screened for eligibility for this retrospective observational cohort study. Demographical and surgical data were collected. The incidence and morphology of medial cortical hinge fractures were evaluated on standard postoperative anterior-posterior knee radiographs. Comprehensive measurements evaluating the osteotomy gap and the position of the osteotomy hinge were taken. Additionally, each osteotomy hinge was assigned to a corresponding sector of a proposed five-sector grid of the distal medial femur.

RESULTS

A total of 100 patients (60% female) with a mean age of 31 ± 13 years were included. The overall incidence of medial cortical hinge fractures was 46% and three distinct fracture types were identified. The most frequently observed fracture type was extension of the osteotomy gap (76%), followed by a proximal (20%) and distal (4%) course of the fracture line in relation to the hinge. Group comparison (hinge fracture vs. no hinge fracture) showed statistically significant higher values for the height of the osteotomy gap (p = 0.001), the wedge angle (p = 0.036), and the vertical distance between the hinge and the proximal margin of the adductor tubercle (AT; p = 0.002) in the hinge fracture group. Furthermore, a significantly lower horizontal distance between the hinge and the medial cortical bone (p = 0.036) was observed in the hinge fracture group. A statistically significant higher incidence of medial cortical hinge fractures was observed when the position of the osteotomy hinge was proximal compared to distal to the proximal margin of the AT (53% vs. 27%; p = 0.023).

CONCLUSION

Medial cortical hinge fractures in LOW-DFO are a common finding with three distinct fracture types. To minimize the risk of medial cortical hinge fractures, it is recommended to aim for a position of the osteotomy hinge at the level of or distal to the proximal margin of the adductor tubercle.

LEVEL OF EVIDENCE

Prognostic study; Level III.

Increased external tibial torsion is an infratuberositary deformity and is not correlated with a lateralized position of the tibial tuberosity

PURPOSE

To perform a segmental analysis of tibial torsion in patients, with normal and increased external tibial torsion, suffering from chronic patellofemoral instability (PFI) and to investigate a possible correlation between tibial torsion and the position of the tibial tuberosity.

METHODS

Patients with chronic PFI who underwent torsional analysis of the lower limb using a standardized hip-knee-ankle MRI between 2016 and 2018 were included. For segmental analysis of tibial torsion, three axial levels were defined which divided the tibia into two segments: a distal, infratuberositary segment and a proximal, supratuberositary segment. Torsion was measured for the entire tibia (total tibial torsion, TTT), the proximal segment (proximal tibial torsion, PTT), and the distal segment (distal tibial torsion, DTT). Based on TTT, patients were assigned to one of two groups: Normal TTT (< 35°) or increased external TTT (> 35°). Position of the tibial tuberosity was assessed on conventional MRI scans by measuring the tibial tuberosity-trochlea groove (TT-TG) and the tibial tuberosity-posterior cruciate ligament (TT-PCL) distances.

RESULTS

Ninety-one patients (24 ± 6 years; 78% female) were included. Mean external TTT was 29.6° ± 9.1° and 24 patients (26%) had increased external TTT. Compared to patients with normal TTT, patients with increased external TTT demonstrated significantly higher values for DTT (38° ± 8° vs. 52° ± 9°; p < 0.001), whereas no difference was found for PTT ( - 13° ± 6° vs.  - 12° ± 6°; n.s.). Furthermore, a significant correlation was found between TTT and DTT (p < 0.001), whereas no correlation was found between TTT and PTT (n.s). With regard to TT-TG and TT-PCL distances, no significant differences were observed between the two groups (TT-TG: 15 ± 6 vs. 14 ± 4 mm, n.s.; TT-PCL: 22 ± 4 vs. 21 ± 5 mm, n.s.) and no correlation was found with TTT, DTT, or PTT (n.s.).

CONCLUSION

In patients with chronic PFI, increased external TTT of greater than 35° is an infratuberositary deformity and does not correlate with a lateralized position of the tibial tuberosity.

LEVEL OF EVIDENCE

Level III.

The "Trigonometric Technique" for simple measurement of volar angulation in boxers' fractures

INTRODUCTION

Subcapital fractures of the 5th metacarpal bone (MCV) represent a common injury. Volar angulation measurement is essential for treatment decision-making and therefore needs a reliable and valid method. The purpose of the present study was to investigate a new technique for volar angulation measurement, called the "Trigonometric Technique" (TT), and to compare the TT with the reference standard based on computed tomography (CT).

HYPOTHESIS

Quantifying volar angulation in MCV neck fractures with the TT shows no difference compared to the angle measured on CT scans.

MATERIAL AND METHODS

Fifteen patients (14 men and 1 woman) with a mean age of 37±16years (range, from 16 to 72 years) who suffered MCV neck fracture and met the inclusion and exclusion criteria were selected for this prospective cohort study. Radiologic investigation included simple dorsopalmar (DP) radiographs and CT scans from the injured hand. Volar angulation measurements were performed by three observers at two time points comparing the TT to measurements obtained on CT scans. Intraclass correlation coefficients (ICC) were determined to assess inter- and intra-observer reliability.

RESULTS

The TT showed a mean volar angulation of 39±5 degrees (range, from 26 to 46 degrees) compared to 41±7 degrees (range, from 28 to 54 degrees) on CT measurement, which revealed a significant correlation between the two measurement techniques (R=0.922, p<0.001). Overall, the inter-rater (R=0.977; 95% CI 0.945-0.992) as well as intra-rater (R=0.857; 95% CI 0.739-0.941) reliability for the volar angulation using the TT was excellent.

CONCLUSION

The TT presented in this study uses plain radiography and trigonometric identities to precisely determine volar angulation in MCV neck fractures. The TT correlates excellently with the obtained volar angulation angles measured on CT scans. We recommend the TT for volar angulation measurement in boxer's fracture as a reliable alternative to the conventional techniques. However, rotational abnormalities may remain undetected and should therefore be ruled out during clinical examination.

LEVEL OF EVIDENCE

II, study of diagnostic test.

Editorial Commentary: Respect the Posterior Tibial Slope and Make Slope-Reducing Osteotomies an Integral Part of the Surgical Repertoire

The posterior tibial slope (PTS), as part of the complex 3-dimensional bony knee morphology, has been a topic of interest for many years but has recently become a hot topic in the scope of reconstructive knee ligament surgery. Biomechanical and clinical evidence suggests that the PTS is an independent and well-accepted risk factor for primary and recurrent anterior cruciate ligament (ACL) injuries. As part of an individualized approach to anatomic ACL reconstruction, the PTS should be respected, and if necessary, addressed, which is especially true for the treatment of multiple failed ACL reconstructions.

Meniscal substitution, a developing and long-awaited demand

The menisci represent indispensable intraarticular components of a well-functioning knee joint. Sports activities, traumatic incidents, or simply degenerative conditions can cause meniscal injuries, which often require surgical intervention. Efforts in biomechanical and clinical research have led to the recommendation of a meniscus-preserving rather than a meniscus-resecting treatment approach. Nevertheless, partial or even total meniscal resection is sometimes inevitable. In such circumstances, techniques of meniscal substitution are required. Autologous, allogenic, and artificial meniscal substitutes are available which have evolved in recent years. Basic anatomical and biomechanical knowledge, clinical application, radiological and clinical outcomes as well as future perspectives of meniscal substitutes are presented in this article. A comprehensive knowledge of the different approaches to meniscal substitution is required in order to integrate these evolving techniques in daily clinical practice to prevent the devastating effects of lost meniscal tissue.

Quantitative Evaluation of Dynamic Lateral Meniscal Extrusion After Radial Tear Repair

Background:

Radial tears of the lateral meniscus frequently accompany acute anterior cruciate ligament (ACL) injuries and lead to increased joint stress and pathological meniscal extrusion (ME). The dynamic behavior of the lateral meniscus after radial tear repair with respect to ME has not been described.

Purpose:

To quantitatively assess dynamic lateral ME after all-inside radial tear repair.

Study Design:

Case series; Level of evidence, 4.

Methods:

Patients who underwent ACL reconstruction and all-inside radial tear repair of the lateral meniscus and had no history of contralateral knee injuries were included. Magnetic resonance imaging scans were acquired in loaded (50% of body weight) and unloaded conditions of both the injured and noninjured knees. A custom-made pneumatically driven knee brace was used for standardized knee positioning in 10° of flexion and with axial load application. Quantitative measures included the absolute lateral ME, meniscal body extrusion ratio, and Δ extrusion. Preoperative and postoperative unloaded extrusion data were compared by paired t tests. For postoperative data, the concomitant influence of the factors “leg” and “condition” were assessed through factorial analyses of variance.

Results:

A total of 10 patients with a mean follow-up of 47.9 months were enrolled. The intraclass correlation coefficient (ICC) confirmed good interrater reliability (ICC, 0.898) and excellent intrarater reliability (ICC, 0.976). In the unloaded injured leg, all-inside repair reduced ME from 3.15 ± 1.07 mm to 2.13 ± 0.61 mm (–32.4%; P = .033). Overall, load application led to a significant increase in ME (+0.34 mm [+21.8%]; P = .029). Significantly greater ME was observed in the injured knee (+1.10 mm [+93.2%]; P = .001) than in the noninjured knee. The condition × leg interaction was not significant (P = .795), suggesting that the compression-associated increase in ME did not differ significantly between the injured and noninjured knees.

Conclusion:

Lateral ME depends on the knee status and loading condition. All-inside repair of radial meniscal tears led to a reduction of extrusion with no alteration in dynamic lateral ME. Meniscus-preserving therapy is recommended in the case of a radial lateral meniscal tear to preserve its dynamic behavior.