Comparison of inside-out and all-inside techniques for the repair of isolated meniscal tears: a systematic review

Neither All-Inside, nor Inside-Out, nor Outside-In Repair Demonstrates Superior Biomechanical Properties for Vertical Meniscal Tears: A Systematic Review of Human Cadaveric Studies

PURPOSE

To systematically review the literature regarding the biomechanical properties of different repair techniques and fixation methods for vertically oriented meniscal tears.

METHODS

Human cadaveric studies evaluating the biomechanical properties of different repair techniques for vertically oriented meniscal tears were identified using the PubMed, EMBASE, and Cumulative Index to Nursing & Allied Health databases. Primary outcomes included load to failure, displacement, stiffness, peak contact pressure, and contact area of repaired menisci. Repair techniques from included studies were reclassified into a total of 19 distinct all-inside (AI), inside-out (IO), or outside-in (OI) techniques.

RESULTS

Sixteen studies were included (420 total menisci). Contact pressure and area were restored to intact-state values across all 5 compressive load studies at low knee flexion angles but not at greater knee flexion angles (i.e., >60°). There were no significant differences in contact pressure or area between AI, IO, and OI techniques across all studies. Some studies demonstrated statistically significant advantages in tensile properties with IO techniques when compared with AI techniques, whereas others found AI techniques to be superior. No studies directly compared tensile properties of OI techniques with those of AI or IO techniques. Vertical mattress suture configurations resulted in significantly greater load to failure and decreased displacement compared with horizontal mattress configurations in 67% of studies comparing the 2 techniques. There was no difference in the rate of tissue failure in AI (66.97%), IO (60.38%), or OI (66.67%, χ2 = 0.83, P = .66) techniques.

CONCLUSIONS

Contact mechanics are reliably restored after repair of vertical meniscal tears at low flexion angles but inconsistently restored at greater flexion angles, regardless of technique. Vertical mattress configurations outperformed horizontal mattress configurations under tensile load. There are conflicting data regarding the comparison of tensile properties between AI and IO techniques. Ultimately, neither AI, IO, nor OI repair demonstrated superior biomechanical properties in the present literature.

CLINICAL RELEVANCE

Several repair techniques demonstrate favorable biomechanical properties for vertical meniscal tears under tensile and compressive loads. Neither AI, IO, nor OI repair techniques demonstrate superior biomechanical properties at this time.

Effect of loading direction and anatomical location on the ultimate tensile stress, fracture toughness, and failure patterns of knee meniscus

BACKGROUND

Rupture of the knee menisci is a common injury that can have implications for other conditions, such as osteoarthritis. The fracture toughness of soft tissue (Jc) is a mechanical property that characterizes its resistance to tear extension. To date, Jc of the meniscus has not been quantified.

METHODS

Cyclic tensile tests were conducted on meniscus samples to determine Jc and explore its characteristics. Initially, the study investigated the impact of an initial notch on the ultimate tensile stress. This allowed for an understanding of how the presence of a notch affects its structural integrity. Subsequently, Jc was measured in both the radial and circumferential directions to assess its loading direction dependency. Furthermore, the study assessed the effect of anatomical location by comparing samples collected from the femoral and tibial layers.

RESULTS

Defect tolerance of the meniscus is influenced by the loading direction. In the circumferential direction, the presence of an initial notch did not affect the ultimate stress, and no crack expansion was observed. In radial samples with a notch length of 40% or more of the total width, crack propagation occurred, leading to a decrease in the ultimate stress (p< 0.01). Additionally, Jc was found to be higher in the femoral layer compared to the tibial layer (p= 0.017).

CONCLUSION

The study also examined the failure patterns of the meniscus to enhance our understanding of its pathology. These insights contribute to a better comprehension of meniscus injuries and can aid in the development of more effective treatment strategies.

Assessing Risk of Iatrogenic Peroneal Nerve Injury in All-Inside Lateral Meniscal Repair Between Standard Vs. Arthroscopic MRI

BACKGROUND

Various studies have examined the risk of peroneal nerve injury with use of standard magnetic resonance imaging (MRI) of the knee. However, the position of the knee during standard MRI is different from that during an actual arthroscopic lateral meniscal repair. The purpose of the present study was to evaluate and compare the risk of peroneal nerve injury during simulated all-inside lateral meniscal repairs on the basis of MRI scans made with the knee in both positions.

METHODS

With use of axial MRI scans made with the knee in the standard position (i.e., in 30° of flexion) and in the actual position used during arthroscopic lateral meniscal repair (i.e., in a figure-of-4 position), direct lines were drawn to simulate the passage of a straight all-inside meniscal repair device from the anteromedial and anterolateral portals to the medial and lateral borders of the popliteus tendon. The distance from the closest passage of each line to the peroneal nerve was measured. If a line touched or passed through the peroneal nerve, a risk of iatrogenic injury was noted and a new line was drawn from the same portal to the outer border of the peroneal nerve. The danger area was measured from the first line to the new line along the joint capsule.

RESULTS

In 28 Thai patients, the shortest distances from each line to the peroneal nerve were significantly shorter on the MRI scans made with the knee in the standard position than on those made with the knee in the arthroscopic position (p < 0.05 for all). All danger areas on the MRI scans that were made with the knee in the arthroscopic position were included within the danger areas on the scans that were made with the knee in the standard position.

CONCLUSIONS

Standard MRI scans of the knee can be used to determine the risk of peroneal nerve injury at the time of arthroscopic lateral meniscal repair, although the risks are slightly overestimated.

LEVEL OF EVIDENCE

Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

More Is Not Merrier: Increasing Numbers of All-Inside Implants Do Not Correlate with Higher Odds of Revision Surgery

The purpose of this study was to evaluate the relationship between the number of all-inside meniscal repair implants placed and the risk of repair failure. We hypothesized that the use of higher numbers of all-inside meniscus repair implants would be associated with increased failure risk. A retrospective chart review identified 351 patients who underwent all-inside meniscus repair between 2006 and 2013 by a sports medicine fellowship-trained orthopaedic surgeon at a single institution. Patient demographics (age, body mass index [BMI], sex) and surgical data (number of implants used, concomitant anterior cruciate ligament reconstruction [cACLR], and tear type/size/location) were recorded. Patients who received repairs in both menisci or who had follow-up < 1-year postoperatively were excluded. Repair failure was identified through chart review or patient interviews defined as a revision surgery on the index knee such as partial meniscectomy, total knee arthroplasty, meniscus transplant, or repeat repair. Logistic regression modeling was utilized to evaluate the relationship between the number of implants used and repair failure. A total of 227 all-inside meniscus repairs were included with a mean follow-up of 5.0 ± 3.0 years following surgery. Repair failure was noted in 68 knees (30.3%)-in 28.1% of knees with fewer than four implants and in 35.8% of knees with four or more implants (p = 0.31). No significant increase in failure was observed with increasing number of all-inside medial (odds ratio [OR]: 1.15; 95% confidence interval [CI]: 0.79-1.7; p = 0.46) or lateral (OR: 0.86; 95% CI: 0.47-1.57; p = 0.63) implants after controlling for patient age, BMI, cACLR, tear type, or size. Tears of the lateral meniscus located in the red-white and white-white zones had lower odds of failure (OR: 0.14; 95% CI: 0.02-0.88; p = 0.036) than tears within the red-red zone, and patients with cACLR had lower odds of repair failure (OR: 0.40; 95% CI: 0.18-0.86, p = 0.024) than those without. The number of all-inside implants placed during meniscus tear repair did not affect the likelihood of repair failure leading to reoperation after controlling for BMI, age, tear type, size, location, and cACLR. LEVEL OF EVIDENCE:  III.

Meniscal Ramp Lesion Repair Without the Need for a Posteromedial Portal

Medial meniscal ramp injury has gained the attention of orthopaedic surgeons in recent years. It consists of a tear of the peripheral insertion of the posterior horn of the medial meniscus. Its prevalence in anterior cruciate ligament reconstruction varies between 9% and 40% according to different studies. Ramp lesions cannot always be diagnosed using magnetic resonance imaging scans. To identify ramp lesions, the arthroscope should be introduced into the posteromedial compartment of the knee during the routine examination of the knee (Gillquist maneuver). Not all authors advocate systematically repairing ramp injuries of the medial meniscus, especially when these injuries are small and stable. They have historically been repaired using an outside-in technique using a hook-type suture passed through a posteromedial portal. In this study, we present our all-inside suture technique without the use of a posteromedial portal.

Biomechanical Comparison of All-Suture, All-Inside Meniscus Repair Devices in a Human Cadaveric Meniscus Model

OBJECTIVE

Newer all-suture, all-inside meniscus repair devices utilize soft suture anchors. The purpose of this study was to compare the biomechanical performance of 4 meniscus repair devices in human cadaver menisci: the JuggerStitch (all-suture, all-inside), the FiberStitch (all-suture, all-inside), a polyether ether ketone (PEEK) all-inside, and an inside-out device.

DESIGN

Forty human cadaver menisci were tested after creating 20 mm longitudinal tears in the posterior meniscus. Each knee was randomized to 1 of 4 meniscus repair groups: JuggerStitch (all-suture, all-inside), FiberStitch (all-suture, all-inside), FAST-FIX 360 (PEEK-based anchor all-inside), and inside-out (with BroadbandTM tape meniscus needles). For each meniscus, 2 devices were used to prepare vertical mattress repair construct. The specimens were tested by pre-conditioning 20 cycles between 5 N and 30 N and then the tear diastasis was measured, followed by distraction to failure phase after imposing a displacement at a rate of 0.5 mm/s.

RESULTS

Ten menisci were tested in each of the 4 groups. After pre-conditioning, there was no significant difference in the gap formation among groups (P = 0.212). The average failure load for the JuggerStitch, FiberStitch, PEEK all-inside, and inside-out was 384 N, 311 N, 207 N, and 261 N, respectively, with a significant difference between groups (P = 0.034). Post hoc analysis showed the JuggerStitch failure load was higher than the PEEK all-inside and inside-out (P = 0.005, and P = 0.045, respectively). There was no significant difference between the failure load of the JuggerStitch and FiberStitch (P = 0.225).

CONCLUSION

The JuggerStitch all-suture device, FiberStitch all-suture device, PEEK all-inside, and inside-out devices have similar biomechanical properties for gapping and stiffness. The JuggerStitch all-suture, all-inside device has superior failure load compared with the PEEK all-inside and inside-out repair for longitudinal meniscus tear repair.

Changes in Functional Meniscal Morphology During Skeletal Growth and Maturation

Background

Little is known on how meniscal morphology develops during skeletal growth and maturation and its subsequent relationship with the corresponding bony anatomy.

Hypotheses

(1) Meniscal dimensions and morphology would change by age during skeletal growth and maturation in different ways in boys compared with girls. (2) Morphological features of the medial and lateral menisci would correlate to medial and lateral femoral condyle curvatures.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Anatomic features of the medial and lateral menisci were measured on magnetic resonance imaging scans from 269 unique knees (age, 3-18 years; 51% female) with no prior history of injury, congenital or growth-related skeletal disorders, or bony deformities. Morphological shape-based measurements were normalized to tibial plateau width or determined as ratios of meniscal dimensions. The association between age and anatomy was analyzed with linear regression. Two-way analysis of variance with the Holm-Šídák post hoc method was used to compare anatomy between sexes in different age groups. Linear regression was used to evaluate the relationship between femoral condyle curvature radius and meniscal morphology in each compartment after adjusting for age and sex.

Results

Meniscal length, width, horn distance, mean cross-sectional area (CSA), and mean height increased with age in both sexes (R2 > 0.1; P < .001). Age-related changes in meniscal morphology were seen in normalized length, width, horn distance, and mean height; width-to-length ratio; horn distance-to-length ratio (lateral meniscus only); normalized mean CSA (except lateral meniscus in girls); and mean tip angle (R2 > 0.04; P < .02). Sex-based differences were also found, with some morphological differences (normalized length and height) throughout development (P < .03) and size differences (length, width, and mean CSA) in later development (P < .01). After adjusting for age and sex, there were significant correlations between medial condyle curvature radius and normalized width, width-to-length ratio, horn distance, horn distance-to-length ratio, mean CSA, and mean height of the medial meniscus (P≤ .041) and between lateral condyle curvature radius and normalized length, mean height, and mean tip angle of the lateral meniscus (P≤ .004).

Conclusion

Age-related changes in meniscal dimensions and morphology, most notably a nonuniform growth pattern in meniscal geometry, occurred during skeletal growth and maturation, with different trends in boys than in girls.

Meniscectomy is associated with a higher rate of osteoarthritis compared to meniscal repair following acute tears: a meta-analysis

PURPOSE

Meniscal tears are common and may impair knee function and biomechanics. This meta-analysis compared meniscal repair versus resection in patients with symptomatic meniscal tears in terms of patient-reported outcomes measures (PROMs), joint width, surgical failure, and rate of progression to osteoarthritis (OA) at conventional radiography.

METHODS

This study was conducted according to the 2020 PRISMA statement. In August 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. Two reviewers independently performed the analysis and a methodological quality assessment of the included studies. All the clinical investigations which compared repair versus resection of meniscal tears were accessed.

RESULTS

Data from 20 studies (31,783 patients) were collected. The mean BMI was 28.28 ± 3.2 kg/m2, and the mean age was 37.6 ± 14.0 years. The mean time elapsed from injury to surgery was 12.1 ± 10.2 months and the mean medial joint width was 4.9 ± 0.8 mm. Between studies comparability at baseline was found in age, women, BMI, time from injury to surgery and length of the follow-up, PROMs, medial joint width, and stage of OA. The resection group demonstrated a greater Lysholm score (P = 0.02). No difference was found in the International Knee Documentation Committee (P = 0.2). Nine studies reported data on the rate of failures at a mean of 63.00 ± 24.7 months. No difference was found between the two groups in terms of persistent meniscal symptoms (P = 0.8). Six studies reported data on the rate of progression to total knee arthroplasty at a mean of 48.0 ± 14.7 months follow-up. The repair group evidenced a lower rate of progression to knee arthroplasty (P = 0.0001). Six studies reported data on the rate of advanced knee OA at a mean of 48.0 ± 14.7 months of follow-up. The repair group evidenced a lower rate of advanced knee OA (P = 0.0001). No difference was found in the mean joint space width (P = 0.09).

CONCLUSION

Meniscal repair is associated with a lower progression to knee osteoarthritis at approximately six years of follow-up compared to partial meniscectomy. No difference in PROMs, medial joint width, and failures were evidenced.

LEVEL OF EVIDENCE

Level III, meta-analysis.

The Risk of Iatrogenic Posterior Neurovascular Injuries in Lateral Meniscal Repair Based on the Standard Arthroscopic Knee Position: A Magnetic Resonance Imaging Study

Background

Repair of the posterior horn of the lateral meniscus using an all-inside meniscal repair device involves the risk of iatrogenic posterior neurovascular injuries. Previous studies that have evaluated this risk were based on preoperative magnetic resonance imaging (MRI) with the knee in 30° of flexion and used landmarks that are impractical in the actual operative situation.

Purpose

To use an MRI model simulating actual knee arthroscopic conditions to (1) compare the potential risk of injuries related to the lateral border of the posterior lateral meniscus root (LMR) through the anterolateral versus anteromedial portal and (2) establish "safe" and "danger" zones to reduce the possibility of injuries to posterior neurovascular structures when performing lateral meniscal repair in relation to the lateral border of the posterior LMR.

Study Design

Descriptive laboratory study.

Methods

Using 29 axial MRI scans of knees in the figure-of-4 position with joint fluid dilatation at the level of the lateral meniscus, direct lines were drawn to simulate a straight all-inside meniscal repair device deployed from the anterolateral and anteromedial portals to the lateral border of the posterior LMR, extending 14 mm beyond the joint capsule. If the line passed through or touched a posterior neurovascular structure, a risk of iatrogenic injuries was noted, and measurements were made to determine the safe zone in relation to the lateral border of the posterior LMR.

Results

Repairing the lateral meniscus through the anterolateral portal in relation to the lateral border of the posterior LMR resulted in a significantly greater risk of posterior neurovascular injuries compared with repairing through the anteromedial portal, with injury incidences of 68.97% and 10.35%, respectively (P = .001). The safe zones of lateral meniscal repair through the anterolateral and anteromedial portals were 4.15 ± 1.87 and 6.57 ± 0.98 mm, respectively, beyond the lateral border of the posterior LMR.

Conclusion

The risk of posterior neurovascular injuries when repairing posterior lateral meniscal tissue was found to be significantly greater through the anterolateral portal compared with the anteromedial portal.

Clinical Relevance

Surgeons can use the safe zones as defined in this study to decrease the risk of iatrogenic posterior neurovascular injuries during arthroscopic lateral meniscal repair.

Failure rate, return-to-sports and magnetic resonance imaging after meniscal repair: 119 patients with 7 years mean follow up

BACKGROUND

One of the most important factors to consider in relation to meniscal repair is the high failure rate reported in the existing literature.

AIM

To evaluate failure rates, return to sports (RTS) rate, clinical outcomes and magnetic resonance image (MRI) evaluation after meniscus suture repair for longitudinal tears at a minimum 2-year-follow-up.

METHODS

We conducted a retrospective review of meniscal repairs between January 2004 and December 2018. All patients treated for longitudinal tears associated or not with an anterior cruciate ligament reconstruction (ACL-R) were included. Meniscal ramp lesions, radial and root tears, associated with multiligament injuries, tibial fracture and meniscal allograft transplants were excluded. Surgical details and failure rate, defined as symptomatic patients who underwent a revision surgery, were analyzed. As isolated bucket handle tears (BHTs) were usually associated with higher failure rates, we compared BHTs and not BHTs associated or not with an ACL-R. Since 2014, the inside-out technique using cannulas and suture needles with 2-0 Tycron began to predominate. In addition, the number of stitches per repair was increased. In view of differences in surgical technique, we compared two different cohorts: before and after 2014. We recorded the RTS according to the level achieved and the time to RTS. Lysholm and IKDC scores were recorded. Patients were studied with x-rays and MRI as standard postoperative control.

RESULTS

One hundred and nineteen patients were included with a mean follow up of 7 years (SD: 4.08). Overall failure rate was 20.3% at a mean 20.1 mo. No statistically significant differences were found when comparing failure for medial and lateral meniscal repair (22.7% and 15.3%, P = 0.36), BHTs and not BHTs (26% and 17.6%, P = 0.27), isolated or associated with an ACL-R (22.9% and 18%, P = 0.47), or when comparing only BHTs associated with an ACL-R (23% and 27.7%, P = 0.9) or not. When comparing cohorts before and after 2014, we found a significant decrease in the overall failure rate from 26% to 11% (P < 0.03). Isolated lesions presented a decrease from 28% to 6.6% (P = 0.02), BHTs from 34% to 8% (P = 0.09) and those associated with an ACL-R from 25% to 10% (P = 0.09). Mean RTS time was 6.5 mo in isolated lesions and 8.64 mo when associated with an ACL-R. Overall, 56% of patients returned to the same sport activity level. Mean pre and postoperative Lysholm scores were 64 and 85 (P = 0.02), and IKDC 58 and 70 (P = 0.03). Out of 84 asymptomatic patients evaluated with MRI, 39% were classified as "not healed" and 61% as "healed".

CONCLUSION

Even though the overall failure rate of our series was 20.3%, we found a statistically significant decrease from 26% to 11%, not only for isolated lesions, but also for BHT's and those associated with an ACL-R when comparing our series in two different cohorts, most probably due to improvements in surgical technique.

Horizontal Cleavage Meniscus Tears: Biomechanics, Indications, Techniques, and Outcomes

» Accounting for up to 24% of all meniscus tears, horizontal cleavage tears (HCTs) are a common pathology orthopaedic practitioners should be comfortable managing.» Historically, HCTs were treated with partial meniscectomy; however, recent studies have demonstrated that these procedures have an adverse biomechanical effect, while HCT repairs restore the knee's natural biomechanics.» Indications for the surgical repair of HCTs remain disputed, but surgery is generally considered for young, active patients and older patients without significant concomitant osteoarthritis.» Early clinical findings surrounding HCT repair are promising. They suggest that this treatment adequately restores meniscus mechanics, leads to good knee functional outcomes, and results in a high likelihood of return to preinjury activity levels.

Using a Combined All-Inside, Inside-Out, and Outside-In Technique to Repair Bucket-Handle Medial Meniscal Tears Without a Safety Incision

We describe a combined all-inside, inside-out, and outside-in technique for the repair of unstable bucket-handle medial meniscal tears. Notably, a greater incidence of neurovascular complications has been associated with meniscal repair techniques that employ an accessory skin incision, especially when damage involves the body of the medial meniscus. However, with the operative knee in relative extension, passing inside-out needles anteromedial to the posterior horn and posterior to the semitendinosus tendon and saphenous nerve allows for the needles to exit the posteromedial knee through a "safe zone." Therefore, we reduce iatrogenic damage by avoiding the necessity of a large safety incision while still maintaining suture placement versatility and meniscal fragment stabilization. Thus, the objective of this Technical Note is to outline an efficient technique for treating bucket-handle medial meniscal tears that yields a strong, durable repair while avoiding damage to adjacent neurovascular structures and eliminating the need for a posteromedial safety incision.

Arthroscopic Meniscus Repair Using an All-Inside, All-Suture, Knotless Device

With an increased appreciation of the importance an intact meniscus has on normal knee kinematics and function, more meniscal tears are being treated with a repair rather than partial meniscectomy. There are several techniques for repairing torn meniscal tissue, including the outside-in, inside-out, and all-inside repairs. Each technique comes with its advantages and drawbacks. The inside-out and outside-in techniques allow for greater control of the repair using knots outside the joint capsule; however, they pose a risk for neurovascular injury and require additional incisions. Arthroscopic all-inside repairs have seen increasing popularity, but with current techniques, fixation is achieved either with intra-articular knots or extra-articular implants, leading to variable outcomes and the potential for postoperative complications. This technical note describes the use of SuperBall, an all-inside meniscus repair device that provides an all-arthroscopic approach, no intraarticular knots or implants, and surgeon-guided tensioning of the meniscus repair.

A Comparison of All-inside and Inside-out Meniscal Repair in Elite Athletes

BACKGROUND

The popularization of all-inside (AI) meniscal repair devices has led to a shift away from the historical gold standard of inside-out (IO) meniscal repair without comparative studies to support the change.

PURPOSE

To compare the failure rate and time to failure of AI and IO meniscal repair performed in elite athletes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective review was performed of all professional and national- and international-level amateur athletes who underwent meniscal repair, with a minimum of 2-year follow-up between January 2013 and September 2019. Meniscal repair was classified as AI or IO depending on the surgical technique performed. Treatment failure was defined as patients having to undergo subsequent surgery to address a persistent meniscal tear after repair. Cox proportional hazards modeling was used to determine if meniscal repair failure rates differed by the location and technique of meniscal repair. Models were controlled for known risk factors such as age, sex, sport, and concurrent cruciate ligament reconstruction.

RESULTS

A total of 192 (135 lateral and 57 medial) meniscal repairs were performed in elite athletes during the study period. Overall, 41 (21%) meniscal repairs met the criteria for failure. Medial meniscal tears repaired with the AI technique failed at a significantly higher rate (18/31 [58%]) than medial meniscal tears repaired with the IO technique (6/26 [23%]) or lateral meniscal tears repaired with the AI (9/76 [12%]) or IO (8/59 [14%]) technique (P < .001). Cox proportional hazards modeling revealed that a medial meniscal tear repaired with the AI technique had an almost 8 times greater hazard of failure than a lateral meniscal tear repaired with the AI technique (P < .001). At 1 year postoperatively, 8% of lateral meniscal repairs had failed (regardless of technique), while medial meniscal tears failed at a rate of 16% with the IO technique and 42% with the AI technique. By 2 years, 53% of medial meniscal tears repaired with the AI technique had failed, and by 5 years, 63% had failed.

CONCLUSION

AI repair of medial meniscal tears led to a higher rate of failure than IO repair of medial or lateral meniscal tears in elite athletes. Medial meniscal repair failed at a higher rate than lateral meniscal repair.

Does Accelerated Rehabilitation Provide Better Outcomes Than Restricted Rehabilitation in Postarthroscopic Repair of Meniscal Injury?

CONTEXT

Meniscal injury is a common pathology, and the postoperative rehabilitation program is essential to patients after surgery. However, the optimal rehabilitation plan after meniscus suture is still controversial.

OBJECTIVE

To compare the clinical outcomes between accelerated rehabilitation and restricted programs in patients with meniscus suture (with or without anterior cruciate ligament reconstruction, ACLR).

EVIDENCE ACQUISITION

Four databases, including PubMed, Ovid, Embase, and the Cochrane Library, were searched up to November 2021. This study only included studies comparing the clinical outcomes between accelerated (immediate range of motion and weight-bearing) and restricted rehabilitation (immobilization and progressive weight-bearing) for meniscus suture. All selected studies were divided into 2 subgroups: isolated meniscus suture or combined with ACLR. The Lysholm score, Tegner score, and Knee Injury and Osteoarthritis Outcome Score were evaluated in simple meniscus sutures no less than 1 year. Failure rate was evaluated in both groups, and the tunnel enlargement was additionally evaluated in patients who underwent ACLR.

EVIDENCE SYNTHESIS

Eleven studies with 612 patients were eligible for analysis. The accelerated group included 4 studies with 330 participants, while the restricted group included 7 studies with 282 participants. For the patients after isolated meniscus suture, the accelerated group achieved higher Lysholm scores (mean difference = -4.66; 95% confidence interval, -8.6 to -0.73; P = .02; I2 = 88%) than the restricted group. For the patients after meniscus suture with ACLR, patients undergoing accelerated rehabilitation were associated with a significantly larger tibial tunnel enlargement in the anterior-posterior view (mean difference = -7.08; 95% confidence interval, -10.92 to -3.24; P = .0003; I2 = 0%) and lateral view (mean difference = -10.33; 95% confidence interval, -16.9 to -3.75; P = .002; I2 = 17%).

CONCLUSION

This meta-analysis evaluated the effects of postoperative rehabilitation in either accelerated or restricted programs in patients with meniscus lesions after repair. A significant higher mean self-reported function was discovered at final follow-ups in the accelerated group. However, a significant increase in tibial tunnel enlargement was also found in accelerated group.

The Popliteal Artery is Safe in Medial Meniscal Repair Using All Inside Devices in Adults: An MRI-Based Simulation Study

Introduction

This simulation study on MRI of the knee was performed to assess the risk of injury to the popliteal artery (PA) and common peroneal nerve (CPN) during all-inside meniscal repairs in adults.

Methods

We simulated repair of the posterior horn of both medial (PHMM) and lateral menisci (PHLM) through anteromedial (AM) and anterolateral (AL) portals, using straight and curved devices, on 200 magnetic resonance imaging (MRI) scans taken with the knee in extension. For simulation using straight devices, the shortest distance from the menisco-capsular junction (MCJ) and the free edge of the meniscus to PA and CPN in vectors of AM and AL portals was measured. In curved devices, the closest extracapsular distance from the device tip to PA was measured.

Results

With a straight device through AM portal, the mean distance from the MCJ of PHMM to the PA was 20.7 ± 3.15 mm (13.5-27.4). In PHMM repair through AM portal using a curved device, the mean extracapsular distance from the device tip to PA was 18.8 ± 4 mm (7.7-27.2) while pointing toward and 26 ± 4.5 mm (15.5-35.6) while pointing away from the midline. When using straight devices, the average distance from free edge of LM to PA was 18.5 ± 3.3 mm (9.6-31.2) and from MCJ to PA was 8.9 ± 2.4 mm (3.5-18.8). The average distance measured from the MCJ to CPN through AM and AL portals using straight devices was 19.4 ± 2.8 mm (10.2-32.5) and 22 ± 2.8 mm (10.4-36.7) respectively.

Conclusion

In adults, PA is safe in PHMM repairs using both straight and curved devices irrespective of depth and direction of insertion. In PHLM repairs, the PA is at risk with both straight and curved devices. We recommend adjusting the depth of insertion to as minimum as possible to just penetrate the capsule. The CPN is safe in LM repairs using all-inside devices.

Level of Evidence

Level IV.

Smaller Iatrogenic Defects Created by Inside-Out Compared With All-Inside Meniscus Repair Devices in Human Cadaveric Model

PURPOSE

(1) To investigate the pattern and diameter of the iatrogenic defect that meniscal repair devices impose on meniscal tissue and (2) to determine whether repair-induced defect patterns or diameters differ across devices.

METHODS

Sixty-one fresh frozen human cadaveric menisci were used (n = 9; eliminated). All-inside devices (n = 9) included ULTRA FAST-FIX, FAST-FIX 360, Depuy Mitek 0° and 12° TRUESPAN, ConMed Sequent, Zimmer Biomet JuggerStitch, Stryker IvyAIR, Arthrex FiberStitch and Meniscal Cinch II. Inside-out needles (n = 4) included ConMed HiFi, Depuy Mitek ORTHOCORD, Arthrex-2-0 FiberWire, and Stryker SharpShooter. Following India Ink staining, implant devices were inserted into cadaveric menisci. Samples were fixed in formalin solution and imaged with a high-resolution camera. Defects were classified by qualitative evaluation. Defect and needle diameter were quantified with software assistance. Statistical analysis was performed using analysis of variance testing.

RESULTS

We analyzed 644 iatrogenic defects with mean defect diameter of 1.96 mm (standard deviation 0.86). For all-inside devices, defect patterns (n = 436) were 15.6% linear, 38.1% semilunar, 46.3% stellate, while inside-out devices (n = 208) were 95.7% stellate, 4.3% linear, and 0.0% semilunar. All-inside devices had mean defect diameter of 2.46 mm, while inside-out meniscus needles had mean 0.90 mm defect diameter (P < .001). FasT-FIX 360, ULTRA-FAST-FIX, and Arthrex Meniscal Cinch II induced smaller diameter defects than other all-inside devices (F = 20.2, P < .05). Strong positive correlation was found comparing outer needle diameter and mean defect diameters across all devices (R² = 0.9447).

CONCLUSIONS

Needles utilized in meniscal implant systems produce the following basic defect patterns: stellate (62.3%), semilunar (25.8%), and linear (11.9%). A strong positive correlation was found between mean defect size and outer needle diameter across all devices. Inside-out double-armed flexible needles produced significantly smaller defects than all-inside devices. Of the all-inside devices, ULTRA FAST-FIX, FAST-FIX 360, and Arthrex Meniscal Cinch II produced smaller defects on average.

CLINICAL RELEVANCE

While the true clinical impact of these findings cannot be drawn from the present study, this investigation provides necessary context to better understand reported similarities and differences in healing rates and outcomes between inside-out and all-inside repair techniques.

Mapping knowledge structure and research trends of knee osteoarthritis with meniscus in two decades: A bibliometric analysis

BACKGROUND

Knee osteoarthritis (KOA) is a chronic degenerative disease that is closely related to the meniscus. Currently, no bibliometric studies have jointly analyzed KOA and the meniscus. This study aimed to provide a comprehensive analysis of the knowledge structure of KOA and the meniscus across two decades and to identify the emerging research trends from a bibliometric perspective.

METHODS

All articles reporting KOA and the meniscus from 2001 to 2021 were obtained from the Web of Science Core Collection. R software, CiteSpace, VOS Viewer, and Microsoft Excel were used to analyze the publications including the authors, cited authors, journals, cited journals, country of research, institutions, and research focus. These data were used to generate visual knowledge maps of the outputs.

RESULTS

A total of 3,218 articles were retrieved. Guermazi was identified as the author who had contributed the most to the field and Osteoarthritis and Cartilage was identified as the most productive research journal. The United States is the global leader in the field and the center for international cooperation with less international collaboration occurring in Eastern Asia. Boston University was the most prolific institution. According to the data, "articular-cartilage," "meniscectomy," "follow-up," "anterior cruciate ligament," and "cartilage" were identified as research hotspots in the field. "Consequences," "prognostic-factors," and "receptor" were predicted as future hot topics of research.

CONCLUSIONS

This study is the first comprehensive bibliometric study to jointly analyze KOA and the meniscus. Our data enable a better understanding of research trends and identify research hotspots and gaps in knowledge across the field. Our findings provide practical information for researchers to better understand the key research areas and identify the research frontiers and future hot topics.

Comparison of Cases with Anterior Cruciate Ligament Reconstruction Accompanied by Simultaneous Medial Meniscus Bucket Handle Tear Repair and Isolated Medial Meniscus Bucket Handle Tear Repair

The aim of this study was to evaluate the success of the all-inside repair technique for medial bucket-handle meniscus tear (BHMT) and the factors affecting healing. A total of 36 patients with BHMT who were operated between 2012 and 2018 and completed final follow-up examinations were included in the study. Functional evaluation was made with the International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score. Healing was evaluated on magnetic resonance imaging (MRI) slices. The patients were evaluated with respect to the effect on healing of factors such as demographic data, body mass index (BMI), smoking status, anterior cruciate ligament tear reconstruction (ACLTR) applied at the same time as BHMT repair, and the tear being chronic or acute. The mean age of the patients was 28.6 ± 8.6 years (range,18-46 years), the mean follow-up period was 25.8 ± 13.9 months (range, 13-59 months), and BMI was mean 25.6 ± 3.5 kg/m² (range, 20.1-30.5 kg/m²). The meniscus tears were acute in 16 (44.4%) patients and chronic in 20 (55.6%). ACLTR was applied together with BHMT repair in 25 patients. The hybrid technique, as the outside-in technique in addition to the all-inside technique, was applied to 12 (33.3%) patients, where there was seen to be extension to the anterior horn. The failure rate was determined as 27.8% according to the postoperative MRI evaluation and the Barrett criteria. No positive or negative statistically significant effect on healing was determined of chronic BHMT or of simultaneous application of ACLTR (p = 1.00 and 0.457, respectively). Cigarette smoking and high BMI were determined to have a statistically significant negative effect on healing (p = 0.026 and 0.007, respectively). In conclusion, it can be seen that the success of the all-inside technique for BHMT remains controversial. Due to the features of the application, it can be used in meniscus tears of the posterior horn only. In the current study, with the success rate of 72.2% of the all-inside technique in meniscus body tears, it was seen that a high success rate could not be achieved.

Several Techniques Exist With Favorable Biomechanical Outcomes in Radial Meniscus Tear Repair-A Systematic Review

PURPOSE

To compare biomechanical properties of various radial tear repair techniques in the medial and lateral menisci.

METHODS

A search was performed for key words regarding mechanical properties of repair of radial meniscal tears in PubMed, Embase, CINAHL, Scopus, and Cochrane databases, yielding 1791 articles. Articles were screened using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines against inclusion criteria and underwent Methodological Index for Non-Randomized Studies (MINORS) methodologic quality assessment. Repair constructs evaluated were classified based on repair technique, use of a transtibial augmentation, and the number, orientation, and pattern of stitches. Results published across different studies were compared but not subjected to meta-analysis due to variability in testing procedures and heterogeneity of repair methods.

RESULTS

We identified 20 studies that performed mechanical testing on 21 different radial meniscal tear repair techniques. The greatest reported mean load-to-failure (LtF) were the transtibial 2-tunnel + 4 horizontal inside-out sutures (191.2 N ± 17.3, cadaver) and all-inside double vertical repair (146.3 N ± 36.2, porcine). The transtibial technique improved LtF and displacement of an inside-out (IO) horizontal repair. All-inside vertical repairs demonstrated greater LtF, stiffness, and displacement compared with IO horizontal repairs in 2 studies. Compared with IO double horizontal repairs, all-inside double vertical or IO double horizontal repairs with reinforcing stitches parallel to the tear exhibited greater LtF in 3 studies and stiffness in 2 studies. Two studies reported that parallel reinforcing stitches significantly reduced suture tear-through compared with similar, nonreinforced repairs. Mean MINORS score for all studies analyzed was 19.88 ± 1.47 points.

CONCLUSIONS

A systematic review demonstrated that there may be alternatives to traditional IO horizontal repairs for radial meniscus tears. Less-invasive all-inside vertical techniques reinforced with suture parallel to the tear instead of standard IO horizontal sutures may improve strength of repair. In addition, transtibial 2-tunnel augmentation may also increase strength of radial meniscus tear repairs.

CLINICAL RELEVANCE

There may be alternatives to IO horizontal repairs for radial meniscus tears.

The Current Role of Biologics for Meniscus Injury and Treatment

PURPOSE OF REVIEW

There is little doubt that the consensus has changed to favor preservation of meniscal function where possible. Accordingly, the indications for meniscal repair strategies have been refocused on the long-term interest of knee joint health. The development and refinements in surgical technique have been complemented by biological augmentation strategies to address intrinsic challenges in healing capacity of meniscal tissue, with variable effects.

RECENT FINDINGS

A contemporary approach to meniscal healing includes adequate surgical fixation, meniscal and synovial tissue stimulation, and management of the intraarticular milieu. Overall, evidence supporting the use of autogenous or allogeneic cell sources remains limited. The use of FDA-approved medications to effect biologically favorable mechanisms during meniscal healing holds promise. Development and characterization of biologics continue to advance with translational research focused on specific growth factors, cell and tissue behaviors in meniscal healing, and joint homeostasis. Although significant strides have been made in laboratory and pre-clinical studies, translation to clinical application remains challenging. Finally, expert consensus and standardization of nomenclature related to orthobiologics for meniscal preservation will be important for the advancement of this field.

The lateral meniscal extrusion after repair with concomitant anterior cruciate ligament reconstruction at a mean follow-up of 3.5 years

BACKGROUND

A meniscal repair is often performed on radial/flap or longitudinal tears of the lateral meniscus (LM) combined with anterior cruciate ligament reconstruction (ACLR). However, it is unknown if meniscal extrusion changes over time after repair. This study evaluated whether meniscal extrusion of the LM is maintained after repair or progresses with time using magnetic resonance imaging (MRI).

METHODS

Among 574 patients who underwent primary anatomic ACLR, 123 patients followed up for more than 2 years were retrospectively analyzed. Forty patients with concomitant radial/flap tears of the LM (group R), 43 with longitudinal LM tears (group L), and 40 with intact LM (group C, matched-control group) were included. Clinical findings (pain, range of motion, swelling, and anterior laxity), lateral joint space on radiograph, and meniscal extrusion on MRI were assessed. Lateral/posterior meniscal extrusions were examined preoperatively, within 3 weeks after surgery, and at the final follow-up, and the absolute values and relative values (the preoperative values as baseline) were assessed respectively.

RESULTS

There were no significant differences in the clinical and roentgenographic findings among the groups. No difference was observed in the relative values within 3 weeks after surgery among three groups, although the absolute values were larger in the repaired groups than in group C. At the final follow-up, however, the lateral extrusion in group L had progressed significantly, compared with that in group C (P = 0.033), while no significant difference was detected in the lateral extrusion between groups R and C (P = 0.177). The posterior extrusion in groups R and L had progressed significantly compared with that in group C (P < 0.001).

CONCLUSIONS

LM extrusion could not be improved even immediately after meniscal repair, and it progressed laterally and posteriorly for more than 2 years after surgery.

All-Inside Meniscus Repair

PURPOSE OF REVIEW

The indications for partial meniscectomy are becoming increasingly limited, and recent evidence suggests that the meniscus should be preserved whenever possible. Because of its many proposed advantages, all-inside meniscus repairs are becoming increasingly common. This review discusses the indications, advantages, disadvantages, and biomechanical and clinical outcomes of all-inside meniscus repair.

RECENT FINDINGS

All-inside meniscus repair demonstrates equal functional outcomes, healing rates, and complications compared to inside-out repair of vertical longitudinal and bucket-handle tears with the advantages of decreased surgical time and faster post-operative recovery. In addition, return-to-sport and activity levels are high following all-inside repair regardless of whether concomitant anterior cruciate ligament reconstruction is performed. Biomechanical studies have demonstrated advantages of all-inside meniscal based repairs on radial and horizontal tears. All-inside meniscus repair compares favorably to inside-out repair of vertical longitudinal and bucket-handle tears and continues to increase in popularity. Both capsular based and meniscal based repairs can be used to repair a variety of tear patterns. While biomechanical results are encouraging, further research on the clinical outcomes of meniscal based repairs is needed to elucidate the role of these techniques in the future.

The Risk of Iatrogenic Peroneal Nerve Injury in Lateral Meniscal Repair and Safe Zone to Minimize the Risk Based on Actual Arthroscopic Position: An MRI Study

BACKGROUND

Lateral meniscal repair using an all-inside meniscal repair device involves a risk of iatrogenic peroneal nerve injury. To our knowledge, there have been no previous studies evaluating the risk of injury with the knee in the standard operational figure-of-4 position with joint dilatation in arthroscopic lateral meniscal repair.

PURPOSE

To evaluate and compare the risk of peroneal nerve injury and establish the safe and danger zones in repairing the lateral meniscus through the anteromedial, anterolateral, or transpatellar portal in relation to the medial and lateral borders of the popliteal tendon (PT).

STUDY DESIGN

Descriptive laboratory study.

METHODS

Using axial magnetic resonance imaging (MRI) studies of knees in the figure-of-4 position with joint fluid dilatation at the level of the lateral meniscus, we drew direct lines to simulate a straight all-inside meniscal repair device deployed from the anteromedial, anterolateral, and transpatellar portals to the medial and lateral borders of the PT. If the line passed through or touched the peroneal nerve, a risk of iatrogenic peroneal nerve injury was noted, and measurements were made to determine the safe and danger zones for peroneal nerve injury in relation to the medial or lateral border of the PT.

RESULTS

Axial MRI images of 29 adult patients were reviewed. Repairing the lateral meniscus through the anteromedial portal in relation to the lateral border of the PT and through the anterolateral portal in relation to the medial border of the PT had a 0% risk of peroneal nerve injury. The "safe zone" in relation to the medial border of the PT through the anterolateral portal was between the medial border of the PT and 9.62 ± 4.60 mm medially from the same border.

CONCLUSION

It is safe to repair the body of the lateral meniscus through the anteromedial portal in the area lateral to the lateral border of the PT or through the anterolateral portal in the area medial to the medial border of the PT.

CLINICAL RELEVANCE

There is a risk of iatrogenic peroneal nerve injury during lateral meniscal repair. Thus, we recommend repairing the lateral meniscal tissue through the anteromedial portal in the area lateral to the lateral border of the PT and using the anterolateral portal in the area medial to the medial border of the PT, as neither of these approaches resulted in peroneal nerve injury. Additionally, the surgeon can decrease this risk by repairing the meniscal tissue using the all-inside meniscal device in the safe zone area.

Inside-Out Approach to Meniscus Repair: Still the Gold Standard?

PURPOSE OF REVIEW

The purpose of this review is to provide an up-to-date summary on the current literature and trends regarding use of the inside-out approach to meniscus repair. Additionally, the paper describes the authors preferred techniques for inside-out meniscus repair utilizing posteromedial and posterolateral exposures.

RECENT FINDINGS

There has been a substantial increase in recent publications regarding meniscus repair. However, comparisons regarding the optimal repair technique have not been conclusive. Despite the recent increase in use of all-inside devices, multiple investigations with short-to-mid-term follow-up have demonstrated similar rates of meniscus healing between inside-out and all-inside repair techniques. Similarly, current literature describes comparable failure rates of around 20%. There are variations in the profile of complications, with all-inside devices having more implant-related complications and inside-out techniques with higher neurovascular injuries. Inside-out meniscus repair is a versatile, cost-effective technique that remains the gold standard for management of most meniscus tear patterns. Through a thoughtful approach, efficient suture retrieval and repair can be performed while protecting critical neurovascular structures. All-inside meniscus repair devices have increased in popularity and surgeon access, but this technique is not without limitations and comparisons to inside-out meniscus repair demonstrates equivocal outcomes.

Outcomes and failure rates after revision meniscal repair: a systematic review and meta-analysis

PURPOSE

The purpose of this meta-analysis is to determine the outcomes and failure rates for revision meniscus repairs in patients with re-tears after primary repair failure.

METHODS

A literature search was conducted using PubMed and Embase with the terms "Meniscus," "Meniscal," "Revised," and "Revision." The search strategy was based on the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) protocol and included four articles (79 patients). The search criteria were limited to studies reporting outcomes and failure rates. The exclusion criteria included languages other than English, biomechanical studies, letters to editors, non-full text, review articles, meta-analysis, and case reports.

RESULTS

Four comparative studies with 79 patients (53 males, 26 females) with a mean age of 23.9 ± 6.4 years treated with a revision meniscus repair were included in the final analysis. Within this analysis, we found a failure rate of 25.3% (20 of 79 patients). Of these failed repairs, 30.95% (13 of 42) were of the medial meniscus, and 18.9% (7 of 37) were of the lateral meniscus. In the four articles, the postoperative Tegner sports activity score was found to be 6.1 ± 1.6 (range, 2 to 10). The post-operative Lysholm score was reported in three articles (45 patients). At a mean follow-up of 58.3 ± 23.9 months, the mean post-operative Lysholm score was 89.1 ± 7.6 (range, 38 to 100). The Coleman score for the included articles ranged between 52 and 59.

CONCLUSION

This analysis found that revision meniscus repairs in patients with re-tears after primary repair failure result in clinical outcomes similar to that of primary repairs.

Comparison of new and old all-inside suture devices in meniscal cyst formation rates after meniscal repair

PURPOSE

We compared the magnetic resonance imaging (MRI)-confirmed cyst formation rate after meniscal tear repair using a new all-inside suture device (N group) versus the older all-inside suture device (O group).

METHODS

Between October 2008 and July 2017, 94 consecutive menisci of 89 patients were diagnosed with meniscal tears and underwent arthroscopic meniscal repair using the all-inside suture device. Five of these patients were lost to follow-up within 12 months and were excluded from the study. The remaining 89 menisci were followed up for at least 12 months and were included in this retrospective cohort study. Older all-inside suture devices (FasT-Fix, Ultra FasT-Fix) were used until December 2012, while the new all-inside suture device (FasT-Fix 360) was used from January 2013 onwards. Meniscal cysts were detected on T2-weighted fat-suppressed MRI at 12 months postoperatively. Multiple logistic regression analysis was used to identify demographic and clinical factors associated with the use of the new all-inside suture device and cyst formation.

RESULTS

In total, 36 and 53 menisci were included in the N and O groups, respectively. The incidence of meniscal cysts was significantly greater in the O group (14 out of 53, 26.4%) than in the N group (two out of 36, 5.56%) (P = 0.012). Two patients in the O group had symptomatic cysts that required removal. Multivariate logistic analyses showed that the cyst formation risk significantly decreased after using the new all-inside suture device than the older all-inside suture devices (odds ratio = 0.139; P = 0.04).

CONCLUSIONS

The MRI-confirmed cyst formation rate after meniscal tear repair was significantly lower using the new than the older all-inside suture devices, indicating that the use of a low-profile device may decrease the cyst formation rate.

A systematic review about long-term results after meniscus repair

PURPOSE

Aim of this systematic review was to analyze long-term results after meniscus refixation.

METHODS

A systematic literature search was carried out in various databases on studies on long-term results after meniscus refixation with a minimum follow-up of 7 years. Primary outcome criterion was the failure rate. Secondary outcome criteria were radiological signs of osteoarthritis (OA) and clinical scores.

RESULTS

A total of 12 retrospective case series (level 4 evidence) were identified that reported about failure rates of more than 7 years follow-up. There was no statistical difference in the failure rates between open repair, arthroscopic inside-out with posterior incisions and arthroscopic all-inside repair with flexible non-resorbable implants. In long-term studies that examined meniscal repair in children and adolescents, failure rates were significantly higher than in studies that examined adults. Six studies have shown minor radiological degenerative changes that differ little from the opposite side. The reported clinical scores at follow-up were good to very good.

CONCLUSION

This systematic review demonstrates that good long-term outcomes can be obtained in patients after isolated meniscal repair and in combination with ACL reconstruction. With regard to the chondroprotective effect of meniscus repair, the long-term failure rate is acceptable.

LEVEL OF EVIDENCE

IV.

Testing Hypoxia in Pig Meniscal Culture: Biological Role of the Vascular-Related Factors in the Differentiation and Viability of Neonatal Meniscus

Menisci play an essential role in shock absorption, joint stability, load resistance and its transmission thanks to their conformation. Adult menisci can be divided in three zones based on the vascularization: an avascular inner zone with no blood supply, a fully vascularized outer zone, and an intermediate zone. This organization, in addition to the incomplete knowledge about meniscal biology, composition, and gene expression, makes meniscal regeneration still one of the major challenges both in orthopedics and in tissue engineering. To overcome this issue, we aimed to investigate the role of hypoxia in the differentiation of the three anatomical areas of newborn piglet menisci (anterior horn (A), central body (C), and posterior horn (P)) and its effects on vascular factors. After sample collection, menisci were divided in A, C, P, and they were cultured in vitro under hypoxic (1% O₂) and normoxic (21% O₂) conditions at four different experimental time points (T0 = day of explant; T7 = day 7; T10 = day 10; T14 = day 14); samples were then evaluated through immune, histological, and molecular analyses, cell morpho-functional characteristics; with particular focus on matrix composition and expression of vascular factors. It was observed that hypoxia retained the initial phenotype of cells and induced extracellular matrix production resembling a mature tissue. Hypoxia also modulated the expression of angiogenic factors, especially in the early phase of the study. Thus, we observed that hypoxia contributes to the fibro-chondrogenic differentiation with the involvement of angiogenic factors, especially in the posterior horn, which corresponds to the predominant weight-bearing portion.

Small lateral meniscus tears propagate over time in ACL intact and deficient knees

PURPOSE

To quantify propagation of small longitudinal tears in the lateral meniscus in ACL intact and deficient knees.

METHODS

Using a robotic testing system, 5-Nm of external tibial torque + 5-Nm of valgus torque + 250-N of axial compression was applied to 14 fresh-frozen cadaveric knees while the knees were flexed from 30° to 90°. Knees were divided into two groups: intact (N = 8) and ACL deficient (N = 6). Kinematic data was recorded for four knee states: intact or ACL deficient knee, after posterior arthrotomy, meniscus tear at baseline, and after 500 cycles of the applied loading condition.

RESULTS

Lateral meniscus tear length increased throughout the 500 cycles regardless of the ACL integrity (p < 0.001). Overall, an increase of 28.7% and 26.1% was observed in intact and ACL deficient knees, respectively. In intact knees, external tibial rotation increased with meniscus tear propagation at all flexion angles by up to 45.5% (p = 0.019). In contrast, knee kinematics in ACL deficient knees were not affected by meniscus tear propagation (n.s.). In ACL deficient knees, resultant forces in the lateral meniscus increased at all flexion angles by up to 116.5% (p = 0.012). No differences in forces were observed in the intact knees (n.s.).

CONCLUSION

The data of this study show that small longitudinal tears in the lateral meniscus propagate significantly regardless of the integrity of the ACL and even after only 100 cycles of knee loading. The propagation of such tears altered kinematics and forces in the knee. Therefore, small, longitudinal lateral meniscus tears that are untreated in current clinical practices may propagate when loaded.

Meniscus Repair Techniques

The menisci play a vital role in maintaining knee function and protecting the chondral surfaces. Acute and chronic tears are common injuries among both young athletes and older patients with early degenerative changes. The progression of physiological derangement and chondral injury after meniscus injury and meniscectomy have prompted interest in expanding meniscus repair techniques. Recent literature encourages an attempt at repair in tear patterns previously declared irreparable if the tissue quality allows. The orthopedic surgeon should understand the multitude of techniques available to them and be prepared to combine techniques to optimize the quality of their repair construct. While biological augmentation may show some promising early results, the quality of the current data precludes strong recommendations in their favor.

Posterolateral approach for all-inside arthroscopic lateral meniscus repair in athletes: technique and outcomes

INTRODUCTION

The past 2 decades have been marked by substantial progress in our knowledge of meniscus anatomy, function, and biomechanics, and also by the shifting of the surgical treatment of meniscal lesions from traditional meniscectomy towards arthroscopic repair to get away from the early osteoarthritis associated with meniscectomy. Posterior horn injuries of the lateral meniscus (LM) have been less studied due to their lower incidence and also due to the historical technical complexity of performing a repair in the posterolateral compartment.

MATERIALS AND METHODS

A retrospective analysis of prospectively collected data was performed of all athletic patients who had a peripheral longitudinal tear of the lateral meniscal posterior horn and who underwent at least one repair procedure with a posterolateral approach between 2014 and 2018. The type of injury, extent of lateral meniscal tear, and characteristics of sutures placed were assessed. Clinical assessment included objective and subjective IKDC ratings. The Tegner activity level score was determined before the injury and at the last follow-up visit. Failure was defined as a need for revision surgery. All complications were documented.

RESULTS

The study population comprised 24 athletes with a mean follow-up of 25.2 ± 10 months. The Tegner activity level was exactly the same before the injury as after the surgery. The mean IKDC score significantly increased from 41.8 (12.2) before the surgery to 94.5 (9.1) after. There were four reoperations for failure (16.6%) that required a new suture repair. None of these revised repairs sustained a new failure as of the last follow-up.

CONCLUSION

Despite the long learning curve, the posterolateral approach is a safe and effective technique for longitudinal tears of the posterior horn of the LM. The results of all-inside suture repair through a posterolateral portal are comparable to other techniques.

Meniscal repair: The current state and recent advances in augmentation

Meniscal injuries represent one of the most common orthopedic injuries. The most frequent treatment is partial resection of the meniscus, or meniscectomy, which can affect joint mechanics and health. For this reason, the field has shifted gradually towards suture repair, with the intent of preservation of the tissue. "Save the Meniscus" is now a prolific theme in the field; however, meniscal repair can be challenging and ineffective in many scenarios. The objectives of this review are to present the current state of surgical management of meniscal injuries and to explore current approaches being developed to enhance meniscal repair. Through a systematic literature review, we identified meniscal tear classifications and prevalence, approaches being used to improve meniscal repair, and biological- and material-based systems being developed to promote meniscal healing. We found that biologic augmentation typically aims to improve cellular incorporation to the wound site, vascularization in the inner zones, matrix deposition, and inflammatory relief. Furthermore, materials can be used, both with and without contained biologics, to further support matrix deposition and tear integration, and novel tissue adhesives may provide the mechanical integrity that the meniscus requires. Altogether, evaluation of these approaches in relevant in vitro and in vivo models provides new insights into the mechanisms needed to salvage meniscal tissue, and along with regulatory considerations, may justify translation to the clinic. With the need to restore long-term function to injured menisci, biologists, engineers, and clinicians are developing novel approaches to enhance the future of robust and consistent meniscal reparative techniques.

An Approach to Chronic and Displaced Bucket Handle Meniscal Tear-Assessment, Repair (Push-and-Pull Technique), or Salvage

Meniscal repairs are preferred to meniscectomies to preserve meniscal function and mitigate the risk of degeneration. However, repair of a chronic and displaced bucket handle tear of the meniscus can be technically challenging. We introduce a systematic method for assessment, reduction, repair, or salvage in this situation with an aim of reducing operating time and improving the chance of a favorable outcome. This technique describes repair of a bucket handle tear on the medial meniscus with displacement into the intercondylar notch. An arthroscopic probe is used for reduction and suture tension (push-and-pull technique) when using an all-inside suture device (FAST-FIX 360 repair system; Smith & Nephew) on the middle and posterior part of the tear. The anterior part of the tear is repaired with an outside-in method. If reduction is not possible, then a salvage reduction and hybrid repair is carried out instead. Postoperatively, patients will be nonweight-bearing on the operated limb, and range of motion restricted from 0 to 90° for 6 weeks, with the aim of resuming running by 6 months.

Mid-term evaluation of clinical and functional outcomes after arthroscopic medial longitudinal and bucket-handle meniscus repair

OBJECTIVES

The aim of this study was to evaluate clinical and functional outcomes following the arthroscopic medial meniscal repair.

PATIENTS AND METHODS

A total of 50 patients (42 males, 8 females; mean age: 32.9±7.6 years; range, 17 to 48 years) who underwent arthroscopic repair for longitudinal and bucket-handle medial meniscal tears between March 2005 and October 2011 were retrospectively evaluated. The patients were divided into two groups as those having a longitudinal tear (patient group, n=31) and having a bucket-handle tear (control group, n=19). Preoperative and final follow-up functional outcomes were evaluated using the Lysholm Knee Score (LKS), International Knee Documentation Committee (IKDC) score, Tegner Activity Scale (TAS) score, and Knee Injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

The mean follow-up was 61.7±22.8 (range, 36 to 110) months. The mean preoperative LKS, IKDC score, TAS, and KOOS scores were significantly improved at the final postoperative follow-up (p<0.05). There was no significant difference in functional outcome scores between longitudinal and bucket-handle repairs (p>0.05), and isolated repairs and concomitant meniscal repair and anterior cruciate ligament reconstruction (p>0.05).

CONCLUSION

Arthroscopic meniscal repair provides similar mid-term functional and clinical outcomes for longitudinal and bucket-handle medial meniscal tears. Concomitant meniscal repair does not seem to affect meniscal healing.

Clinical Outcomes of Meniscus Repair with or without Multiple Intra-Articular Injections of Platelet Rich Plasma after Surgery

Preservation of the meniscal volume is crucial in meniscus repair. The goal of this study was to evaluate the clinical outcome of repeated intra-articular platelet-rich plasma (PRP) injections after arthroscopic repair of a traumatic meniscal tear. We retrospectively reviewed 61 primary meniscal repairs in 61 patients (PRP group: 30; non-PRP: 31) from 2017 to 2018. Patients in the PRP group received repeated intra-articular PRP injections in week 2,4,6 after the primary meniscus repair. Subsequent meniscal repair treatment or meniscectomy, knee arthroplasty, and IKDC changes of less than 11.5 points were defined as healing failures. After following up for at least 24 months, the IKDC score was 75.1 ± 13.6, and the Lysholm score was 80.6 ± 14.9 in the PRP group and 72.6 ± 15.8 (IKDC) and 77.7 ± 17.2 (Lysholm) in the non-PRP group. Healing rates of the PRP and the non-PRP groups were 93.3% (Kaplan-Meier 91.6%) and 87.1% (Kaplan-Meier 84.7%), respectively (log rank test p = 0.874). Our study is the first to use multiple intra-articular PRP injections to facilitate meniscal healing after meniscal repair. Though selection bias may be present in this study, the PRP group had similar functional outcome and healing rate compared to non-PRP group.

Bucket handle meniscus tears in low-resource settings can be successfully treated with a cost-effective technique

PURPOSE

In regions of the world where resources can limit medical care (limited-resource settings, LRS), most meniscal tears are often treated with meniscectomy. A simple, low-cost option for meniscal repair has been developed. We sought to evaluate patient reported outcomes (PROMs) and clinical failure rates of bucket handle meniscus tears (BHTs) treated with meniscal repair in a LRS.

METHODS

We prospectively enrolled patients over 18 who were treated for BHT with meniscal repair in a LRS. Meniscal repair was primarily accomplished using an outside-in technique. Pre-injury and final follow-up PROMs were recorded. Clinical failure was defined as the need for re-operation or symptoms that prevented the patient from returning to recreational activities or work responsibilities.

RESULTS

Nineteen patients with a mean age of 25.4 years were eligible. Two patients sustained a clinical failure (10.5%). At mean follow-up of 40.6 months, there was significant improvement in all PROMs from baseline. Subgroup analysis revealed no significant difference in the failure group compared to the success group in number of knots used, pre-injury Tegner score, number of devices used, suture type, or technique.

CONCLUSION

Bucket-handle meniscal tears can be repaired using a low-cost technique resulting in satisfactory healing rates and excellent outcomes.

Ramp lesion of the medial meniscus

Ramp lesion of the medial meniscus used to be completely disregarded in the past.

Ramp lesion has been now put under the spotlight by orthopaedic and sport medicine surgeons and requires attention.

It is closely associated with anterior cruciate ligament injury. Major risk factors include chronic laxity, lateral meniscal lesion, anterior cruciate ligament reconstruction revision, anterolateral ligament tear concomitant with anterior cruciate ligament injury, time from injury, pre-operative side-to-side laxity > 6 mm, age < 30 years old, male sex, etc.

Radiologists attempt to create diagnostic criteria for ramp lesion using magnetic resonance imaging. However, the only definite method to diagnose ramp lesion is still arthroscopy. Various techniques exist, among which posteromedial approach is the most highly recommended.

Various treatment options are available. The success rate of ramp repair is very high. Major complications are uncommon.

Cite this article: EFORT Open Rev 2021;6:372-379. DOI: 10.1302/2058-5241.6.200126

Long-term National Trends of Arthroscopic Meniscal Repair and Debridement

BACKGROUND

Optimal treatment of meniscal pathology continues to evolve in orthopaedic surgery, with a growing understanding of which patients benefit from which procedure and which patients might be best treated nonsurgically. In 2002, Moseley et al found no difference between arthroscopic procedures, including meniscal debridement and sham surgery, in patients with osteoarthritis of the knee. This called into question the role of routine arthroscopic debridement in these patients. Additionally, an increased interest in understanding and maintaining the function of the meniscus has more recently resulted in a greater focus on meniscal preservation procedures.

STUDY DESIGN

Descriptive epidemiology study.

PURPOSE/HYPOTHESIS

The purpose was to evaluate the trends of arthroscopic meniscal debridement and repair and the characteristics of the patients receiving these treatments, compare the differences in practice between newly trained orthopaedic sports medicine specialists and those of other specialties, and analyze if there are differences in practice by region. It was hypothesized that the American Board of Orthopaedic Surgery (ABOS) database would evaluate practice patterns of recent graduates as a surrogate for current treatment and training and, consequently, demonstrate a decreased rate of meniscal debridement.

METHODS

Data from ABOS Part II examinees from 2001 to 2017 were obtained from the ABOS Case List. Current Procedure Terminology (CPT) codes related to arthroscopic meniscal treatment were selected. The examination year, age of the patient, practice region, and examinee subspecialty were analyzed. Patient age was stratified into 4 groups: <30, 30 to 50, 51 to 65, and >65 years. Examinee subspecialty was stratified into sports medicine and non-sports medicine. Statistical regression analysis was performed.

RESULTS

Between 2001 and 2017, ABOS Part II examinees submitted 131,047 cases with CPT codes 29880 to 29883. Meniscal debridement volume decreased for all age groups during the study period, while repair increased. Sports medicine subspecialists were more likely than their counterparts to perform repair over debridement in patients aged younger than 30 years (P = .0004) and between 30 and 50 years (P = .0005).

CONCLUSION

This study provides insights into arthroscopic meniscal debridement and repair practice trends among ABOS Part II examinees. Meniscal debridement is decreasing and meniscal repair is increasing. Younger patient age and treatment by a sports medicine subspecialty examinee are associated with a higher likelihood of repair over debridement.

The Role of the Pie-Crusting Technique of the Medial Collateral Ligament in the Arthroscopic Inside-out Technique for Medial Meniscal Repair With or Without Anterior Cruciate Ligament Reconstruction: A Satisfactory Repair Technique

Purpose

To assess the results of a technique for pie crusting of the medial collateral ligament (MCL) and inside-out medial meniscal repair and perform a comparison with the literature.

Methods

This retrospective study consisted of electronic data collection between 2012 and 2017 with a minimum of 2 years’ follow-up. The inclusion criteria were the presence of difficult medial meniscal tears with joint tightness requiring pie crusting and the presence of acute or chronic tears of zone I or II with or without anterior cruciate ligament reconstruction (ACLR) using hamstring autograft during the same session. The primary outcome of the study was the achievement of good results with the aforementioned technique. There was no control group. All patients underwent assessments at 1, 2, and 6 months in outpatient clinics. At 6 months, the Lysholm knee score was calculated. For statistical analysis, the Social Science Statistics online program was used to perform descriptive analysis and assess any associations between the variables.

Results

This study included 53 patients from a single surgeon’s practice; of these patients, 31 underwent additional ACLR using hamstring autograft during the same session. The mean age was 29.43 years (range, 14-49 years), and the mean increase in the medial joint space width was 3.21 mm (range, 2-5 mm) with pie crusting. At 6 months, the average Lysholm score was 93 (range, 67-100) and the average visual analog scale score was 0.8 (range, 0-4). There was no meaningful association between age, tear pattern, chronicity of tear, joint space width obtained after pie crusting, and associated anterior cruciate ligament tear. Patients returned to their daily activity level at 4.5 months on average and returned to sporting activities at 7.4 months on average. Saphenous nerve symptoms were observed in 5 patients, but no infection or instability was documented in the follow-up period.

Conclusions

In this study, we obtained good outcomes using arthroscopic inside-out medial meniscal repair combined with pie crusting for the release of the MCL, with or without ACLR.

Level of Evidence

Level IV, therapeutic case series.

Inside-out Medial Meniscal Repair: Improved Surgical Exposure With a Sub-semimembranosus Approach

Inside-out meniscal repair is considered the gold standard for reparable tears of the medial and lateral menisci despite the recent popularity of all-inside devices. Accurate suture passage is required to perform a stable repair as well as to prevent inadvertent neurovascular injury from the suture needles. Placement of a deep soft-tissue retractor is necessary to identify and retrieve these needles prior to tying the sutures. Several authors have recommended placement of this retractor in the interval anterior to the gastrocnemius muscle belly and above the semimembranosus tendon. However, we have noted that the needles often pass distal to the retractor when it is placed in this interval owing to the reorientation of the joint line that occurs with the knee in a relatively extended position during suture placement. We describe a modified technique in which the retractor is placed inferior to the semimembranosus, which puts it directly in line with the needles' trajectory. This modification makes inside-out medial meniscal repair safer and more efficient.

Assessing the Resident Progenitor Cell Population and the Vascularity of the Adult Human Meniscus

PURPOSE

To identify, characterize, and compare the resident progenitor cell populations within the red-red, red-white, and white-white (WW) zones of freshly harvested human cadaver menisci and to characterize the vascularity of human menisci using immunofluorescence and 3-dimensional (3D) imaging.

METHODS

Fresh adult human menisci were harvested from healthy donors. Menisci were enzymatically digested, mononuclear cells isolated, and characterized using flow cytometry with antibodies against mesenchymal stem cell surface markers (CD105, CD90, CD44, and CD29). Cells were expanded in culture, characterized, and compared with bone marrow-derived mesenchymal stem cells. Trilineage differentiation potential of cultured cells was determined. Vasculature of menisci was mapped in 3D using a modified uDisco clearing and immunofluorescence against vascular markers CD31, lectin, and alpha smooth muscle actin.

RESULTS

There were no significant differences in the clonogenicity of isolated cells between the 3 zones. Flow cytometry showed presence of CD44⁺CD105⁺CD29⁺CD90⁺ cells in all 3 zones with high prevalence in the WW zone. Progenitors from all zones were found to be potent to differentiate to mesenchymal lineages. Larger vessels in the red-red zone of meniscus were observed spanning toward red-white, sprouting to smaller arterioles and venules. CD31⁺ cells were identified in all zones using the 3D imaging and co-localization of additional markers of vasculature (lectin and alpha smooth muscle actin) was observed.

CONCLUSIONS

The presence of resident mesenchymal progenitors was evident in all 3 meniscal zones of healthy adult donors without injury. In addition, our results demonstrate the presence of vascularization in the WW zone.

CLINICAL RELEVANCE

The existence of progenitors and presence of microvasculature in the WW zone of the meniscus suggests the potential for repair and biologic augmentation strategies in that zone of the meniscus in young healthy adults. Further research is necessary to fully define the functionality of the meniscal blood supply and its implications for repair.

All-inside versus inside-out meniscal repair: A systematic review and meta-analysis

BACKGROUND

Meniscal repair using all-inside devices has garnered popularity compared to inside-out repair, yet few studies directly compare the two techniques in terms meniscal healing rates, surgical time, patient outcomes and incidence of complications.

METHODS

A systematic literature review was performed using the Medline, Cochrane and Embase databases. English-language studies comparing all-inside and inside-out arthroscopic meniscal repair techniques directly were included. Randomised controlled trials (RCTs) and observational studies with at least 10 patients in each treatment arm were included. Meta-analyses were performed using a fixed effect (when I2 < 50%) or random effects model (I2 ≥ 50%).

RESULTS

A total of 1042 studies were identified with seven being sui for inclusion (n = 505 patients). These comprised of one RCT two prospective and four retrospective, comparative, observational studies. Meta-analyses demonstrated that there was a significant reduction in operating time favouring all-inside repair (ratio of means [ROM] 0.62, 95% confidence interval [CI] 0.48-0.79; p = 0.0002) based on 3 studies (n = 208 patients). Based on 5 studies (n = 370 patients), there was no significant difference in meniscal healing rates between the groups (OR 1.26, 95% CI 0.52-3.10; p = 0.61). Nerve injury was more common after inside-out repair. There was a 85% reduction in the odds of nerve injury with the all-inside technique (OR 0.15, 95% CI 0.05-0.47; p = 0.0013). A qualitative data analysis suggested no difference in functional outcomes between the two techniques.

CONCLUSIONS

All-inside meniscal repair is associated with reduced operative time and a lower odds of nerve injury complications compared to inside-out repair, without compromising meniscal healing or functional results.

Return to Play After Isolated Meniscal Repairs in Athletes: A Systematic Review

Background:

Meniscal tears are a common knee injury. Isolated meniscal tears are less common; however, unaddressed tears can be troublesome, particularly for athletes. There is currently a lack of data in the literature on athletes returning to play after isolated meniscal repair.

Purpose:

To evaluate the return to play rate and time to return to play for athletes with isolated meniscal injuries.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A search of the PubMed, EMBASE, and Cochrane electronic databases was conducted to identify studies that reported the time and the rate of return to play in athletes after repair of isolated meniscal tears. Studies were excluded if there was a concomitant anterior cruciate ligament reconstruction, if there was a meniscectomy instead of a meniscal repair, or if the study was a systematic review. Quality assessment and data extraction were performed by 2 examiners.

Results:

Overall, 21 studies were included in this review. There were 355 athletes (358 knees) with a mean age of 22.5 years (range, 9-68 years). A sex breakdown was noted in 16 of the 21 (76.2%) studies with 224 men and 71 women. The specific repair technique was described in 259 (72.3%) knees. Of the total knees, 109 (30.4%) had an open repair, 128 (35.8%) had an inside-out arthroscopic technique repair, and 22 (6.1%) had an all-inside arthroscopic technique repair. Complications were addressed in 11 studies, with 13 out of 155 (8.4%) patients across the 11 articles having a postoperative complication. Of the total 355 patients, 295 (83.1%) returned to play, and 17 of these 21 (81.0%) articles reported the time it took for athletes to return to play, with a mean return of 8.7 months.

Conclusion:

The study results indicate that return to play rates after isolated meniscal repair are high, with an overall return to play rate of 83.1% and a mean return to play time of 8.7 months. However, the limited number of studies, particularly ones with larger patient numbers, highlights the need for further investigation regarding isolated meniscal repair in athletes.

Platelet-Rich Plasma Augmentation for Isolated Arthroscopic Meniscal Repairs Leads to Significantly Lower Failure Rates: A Systematic Review of Comparative Studies

Background:

Studies have reported relatively high failure rates of isolated meniscal repairs. Platelet-rich plasma (PRP) has been suggested as a way to increase growth factors that enhance healing.

Purpose:

To compare (1) meniscal repair failures and (2) patient-reported outcomes after isolated arthroscopic meniscal repair augmented with and without PRP.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

A systematic review was performed using the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines. Multiple databases were searched for studies that compared outcomes of isolated arthroscopic meniscal repair augmented with PRP versus without PRP in human patients. Failures and patient-reported outcome scores were reported for each study and compared between groups. Study heterogeneity was assessed using I² for each outcome measure before meta-analysis. Study methodological quality was analyzed. Continuous variable data were reported as mean and standard deviation from the mean. Categorical variable data were reported as frequency with percentage. All P values were reported with significance set at P < .05.

Results:

Five articles were analyzed (274 patients [110 with PRP and 164 without PRP]; 65.8% male; mean age, 29.1 ± 4.6 years; mean follow-up, 29.2 ± 22.1 months). The risk of meniscal repair failure ranged from 4.4% to 26.7% for PRP-augmented repairs and 13.3% to 50.0% for repairs without PRP. Meniscal repairs augmented with PRP had significantly lower failure rates than repairs without PRP (odds ratio, 0.32; 95% CI, 0.12-0.90; P = .03). One of the 5 studies reported significantly higher outcomes in the PRP-augmented group versus the no-PRP group for the International Knee Documentation Committee (IKDC), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Knee injury and Osteoarthritis Outcome Score (KOOS) (P < .05 for all). The remaining 4 studies reported no significant difference between groups with regard to outcomes for the IKDC, Lysholm knee scale, visual analog scale for pain, or Tegner activity level.

Conclusion:

Although the studies were of mostly of low quality, isolated arthroscopic meniscal repairs augmented with PRP led to significantly lower failure rates (10.8% vs 27.0%; odds ratio, 0.32; P = .03) as compared with repairs without PRP. However, most studies reported no significant differences in patient-reported outcomes.

All-Inside Repair of Bucket-Handle Meniscal Tears: Clinical Outcomes and Prognostic Factors

BACKGROUND

There is no consensus on technique of choice for repair of bucket-handle meniscal tears (BHMTs).

PURPOSE

To determine factors that affect patient outcomes and failure rates in patients undergoing all-inside repairs of BHMTs.

STUDY DESIGN

Systematic review.

METHODS

A systematic review of 3 databases using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed. All English-language literature from 1993 to 2019 describing clinical outcomes for patients undergoing all-inside BHMT repair with ≥12-month follow-up was reviewed by 2 independent reviewers. Patient characteristics (patient sex, age), intraoperative factors (laterality, concomitant procedures, surgical technique, implants utilized), and postoperative outcomes (failure rates) were analyzed. Study quality was evaluated with the Modified Coleman Methodology Score (MCMS).

RESULTS

Fifteen studies (1 level 1, 4 level 3, 10 level 4) with 763 total patients (64% male; average age, 26.4 years [range, 9-58 years]; average follow-up, 39.8 months [range, 12-120 months]) including 396 all-inside BHMT repairs were included. Six devices were used for repair including the Meniscal Repair System, FasT-Fix, Meniscus Arrow, Biofix Arrow, RapidLoc device, and PDS II suture, with failure rates of 13.5%, 22.4%, 27.1%, 42.9%, 45.2%, and 0%, respectively. The overall repair failure rate was 29.3% at an average of 13.0 months (range, 5.0-32.4 months), but 19.0% for devices still in use. The RapidLoc and Biofix Arrow had higher failure rates than other devices (P = .0003). Women (31%) were less likely to experience a failure than were men (69%) (P = .03). Longer follow-up duration resulted in higher failure rates (>30 months, 34.4%; <30 months, 23.4%; P = .016). In 4 studies reporting on both all-inside and inside-out repairs, no significant differences in failure rates were observed. No significant differences in failure rates were found between medial and lateral repairs nor repair with and without concurrent anterior cruciate ligament reconstruction (P > .05 for all). The overall average MCMS was 54.4 ± 12.

CONCLUSION

The overall failure rate after all-inside repair of BHMTs is 29.3% at an average of 13.0 months, with no difference in failure rates between medial and lateral meniscal repairs. The variables shown to negatively affect the failure rates were the RapidLoc and Biofix Arrow, male sex, and longer follow-up duration.

The all-inside all-suture technique demonstrated better biomechanical behaviors in meniscus radial tear repair

PURPOSE

The purpose of this study was to evaluate the effectiveness of three constructs and techniques for repair of radial tears of the meniscus.

METHODS

Thirty fresh frozen porcine menisci were divided equally into three groups consisting of (1) inside-out repair group, (2) a commonly used all-inside suture with anchor hybrid repair construct (AISAH) (Meniscal Cinch™), and (3) an all-inside all-suture repair construct (AIAS) (Knee Scorpion™). Radial tears were created and repaired and then the menisci were secured to the materials testing machine. Both cyclic loading and load-to-failure testing were performed. The displacement, stiffness, response to cyclic loading, and mode of failure were recorded and analyzed statistically.

RESULTS

The displacement after cyclic loading (DACL) of the Cinch repair construct group was significantly higher than that of the inside-out repair construct group (p = 0.000) and AIAS repair construct (p = 0.000). There was not a statistical difference of DACL between inside-out and AIAS groups (n.s.). The inside-out construct failed at a significantly higher load than the AISAH repair construct (p = 0.000) and AIAS construct (p = 0.006). The AIAS construct failed at a significantly higher load than the AISAH repair construct (p = 0.009). The AIAS had a higher stiffness than AISAH (p = 0.047). The AIAS had a higher load at 3 mm protrusion than AISAH (p = 0.034).

CONCLUSION

The AIAS repair construct had better biomechanical behaviors than AISAH construct and inside-out repair technique. Inside-out sutures and AIAS repair construct had similar biomechanical responses to cyclic loading. The AIAS can be used for meniscus tear surgical repair with less damage to peri-meniscus tissues.