Improved tibiofemoral contact restoration after transtibial reinsertion of the anterior root of the lateral meniscus compared to in situ repair: a biomechanical study

Meniscus root tears: state of the art

BACKGROUND

Meniscus root tears represent significant pathology that, historically, has been underdiagnosed and undertreated. However, the recognition of their clinical and functional significance has recently surged, mainly due to their frequent association with anterior cruciate ligament injuries.

AIM

This comprehensive review discusses various aspects of meniscal root tears, including their epidemiology, biomechanics, etiology, clinical and radiological findings, classification, management and surgical techniques.

Arthroscopy with partial meniscectomy for degenerative tear does not increase the risk of total knee arthroplasty at five year follow up; however, this population undergoes total knee arthroplasty with a lower threshold of osteoarthritis

PURPOSE

Degenerative meniscus tears can cause discomfort in some patients, and when medical treatments fail to provide relief, arthroscopy may be considered before resorting to knee prosthesis. However, the benefits of arthroscopy over nonsurgical treatments in patients over 60 years old are limited, and the evidence regarding its overall efficiency and drawbacks remains scarce. Furthermore, there has been no investigation into whether those patients treated with partial meniscectomy, undergo the knee operation at an earlier stage of osteoarthritis.

METHODS

This study focused on data from a single Belgian hospital, involving patients over 60 years old with internal meniscal tears. The participants were categorized into two groups based on the treatment they received: arthroscopic partial meniscectomy (APM) or conservative management. The primary outcome assessed was the occurrence of knee arthroplasty within a five year period. Secondary outcomes included evaluating the ICRS cartilage grade and the time taken until total knee arthroplasty (TKA).

RESULTS

A total of 194 patients with internal meniscal tears were included in the study. At the 5-year mark, the overall rate of knee arthroplasty was found to be 16.5%, with 11.9% of cases occurring within two years. After the 5-year follow-up, it was observed that 19.2% (24 patients) of the APM group and 11.6% (8 patients) of the conservative management group underwent knee arthroplasty. Notably, patients over 70 years old who underwent APM had a higher risk of eventually requiring TKA compared to those who received conservative management. Additionally, patients who underwent meniscectomy and later underwent TKA showed less wear in the internal compartment of the knee compared to patients in the conservative treatment group who underwent TKA.

CONCLUSION

The study suggests that patients who underwent arthroscopy faced a similar risk of knee arthroplasty compared to those who underwent conservative management, excepted for patients over 70 years old. Despite this similar risk of arthroplasty for the whole population, they exhibited lower osteoarthritis severity when compared to the conservative group.

Age influence on resistance and deformation of the human sutured meniscal horn in the immediate postoperative period

Introduction: To preserve knee function, surgical repair is indicated when a meniscal root disinsertion occurs. However, this surgery has not yet achieved complete recovery of the joint´s natural biomechanics, with the meniscus-suture interface identified as a potentially determining factor. Knowing the deformation and resistance behavior of the sutured meniscal horn and whether these properties are preserved as the patient ages could greatly contribute to improving repair outcomes. Methods: A cadaveric experimental study was conducted on human sutured menisci classified into three n = 22 age groups (young ≤55; 55 < middle-aged ≤75; 75 < old) were subjected to load-to-failure test by suture pulling. Meniscal thickness at the suture hole was measured and the applied traction force and tissue deformation in the suture area in the direction of traction were recorded during the test. The traction load that initiated the meniscal cut-out, F c , maximum load borne by the meniscus, F u , tissue stress at the cut-out initiation, S c , and equivalent stiffness modulus at the suture area, m s , were calculated. Results: At the tissue level, the resistance in terms of S c decrease with age (young: 47.2 MPa; middle-aged: 44.7 MPa; old: 33.8 MPa) being significantly different between the young and the old group (p = 0.015). Mean meniscal thickness increased with age (young: 2.50 mm; middle-aged: 2.92 mm; old: 3.38 mm; p = 0.001). Probably due to thickening, no differences in resistance were found at the specimen level, i.e., in F c (overall mean 58.2 N) and F u (overall mean 73.6 N). As for elasticity, m s was lower in the old group than in the young group (57.5 MPa vs. 113.6 MPa, p = 0.02) and the middle-aged one (57.5 MPa vs. 108.0 MPa, p = 0.04). Conclusion: Regarding the influence of age on the sutured meniscal horn tissue, in vitro experimentation revealed that meniscal horn specimens older than 75 years old had a more elastic tissue which was less resistant to cut-out than younger menisci at the suture hole area. However, a thickening of the meniscal horns with age, which was also found, leveled out the difference in the force that initiated the tear, as well as in the maximum force borne by the meniscus in the load-to-failure test.

[Treatment of tibial insertion avulsion fracture of anterior cruciate ligament involving anterior root of lateral meniscus with multi-point fixation with anchor and suture]

Objective

To investigate the effectiveness of arthroscopic multi-point fixation with anchor and suture in the treatment of tibial insertion avulsion fracture of anterior cruciate ligament (ACL) involving the anterior root of lateral meniscus (LM).

Methods

A retrospective analysis was conducted on the clinical data of 28 patients with tibial insertion avulsion fracture of ACL involving the anterior root of LM who were treated with arthroscopic multi-point fixation with anchor and suture between October 2017 and January 2023. There were 12 males and 16 females with the mean age of 26 years (range, 13-57 years). There were 20 cases of sports injury and 8 cases of traffic accident injury. In 2 cases of old fracture, the time from injury to operation was 45 days and 90 days, respectively; in 26 cases of fresh fracture, the time from injury to operation was 3-20 days (mean, 6.7 days). According to the Meyers-McKeever classification, there were 4 cases of type Ⅱ, 11 cases of type Ⅲ, and 13 cases of type Ⅳ. The preoperative Lysholm knee function score was 42.1±9.0, the International Knee Documentation Committee (IKDC) score was 40.0±7.3, and the Tegner score was 0.7±0.7.

Results

All operations were successfully completed, and the incisions healed by first intention. All the 28 patients were followed up 5-60 months (mean, 20.4 months). During the follow-up, there was nocomplication such as infection, vascular or nerve injury, loosening or breakage of internal fixator, or stiffness of knee joint. Postoperative X-ray films showed satisfactory fracture reduction and firm fixation. All fractures healed clinically, and the healing time was 8-16 weeks (mean, 10.3 weeks). At last follow-up, Lachman test and anterior drawer test were negative. At last follow-up, Lysholm knee function score was 92.4±5.5, IKDC score was 91.6±4.4, and Tegner score was 5.2±1.1, which significantly improved when compared with preoperative scores ( t=-22.899, P<0.001; t=-29.870, P<0.001; t=-19.979, P<0.001).

Conclusion

Multi-point fixation with anchor and suture in the treatment of tibial insertion avulsion fracture of ACL involving the anterior root of LM can not only fix the LM, but also effectively reduce and fix the avulsion fracture, which can obtain good effectiveness.