Editorial Commentary: Morton Forks a Knee: Magnetic Resonance Imaging Versus Needles Arthroscopy for Knee Meniscus Tears

Recent literature tells us that knee arthroscopy in the setting of osteoarthritis is no better than placebo, but arthroscopy for isolated, nondegenerative meniscus tears is both helpful to patients and cost-effective. Since most patients with osteoarthritis have meniscus pathology, we need an accurate way to rule out degenerative disease in patients who are otherwise good candidates for arthroscopic partial meniscectomy. Magnetic resonance imaging can be misleading. Needle arthroscopy is a new tool that can potentially help dig us out of this diagnostic dilemma.

Editorial Commentary: We Know We Need to Fix Knee Meniscal Radial Root Tears-But How Best to Perform the Repairs?

The present work further contributes to building the base of the research pyramid by noting the importance of repairing knee meniscal radial root tears. Because of the extensive biomechanical studies that have now been published on the restoration of joint mechanics and with what I believe results in a higher likelihood of an improved healing environment with securing the meniscus root tear down to bone, I would strongly recommend that when one does see a meniscus root tear that the transtibial pullout root repair technique be considered over a side-to-side repair. The biggest challenge going forward is to validate and improve the healing potential of knee meniscal radial root repairs.

Editorial Commentary: Feeling the Pressure! A Biomechanical Analysis of All-Inside and Inside-Out Knee Meniscus Repair

A biomechanical, time-zero comparison found that both No. 2-0 UltraBraid inside-out sutures and FasT-Fix 360 all-inside devices used to repair a displaced bucket handle knee meniscus tear increased the contact area in deeper flexion angles (at 45°-60°) and reduced the peak contact pressure (at 45°-90°). No significance difference was observed between the inside-out and all-inside repair techniques.

Role of the C-C chemokine receptor-2 in a murine model of injury-induced osteoarthritis

OBJECTIVE

We previously found in our embryonic studies that proper regulation of the chemokine CCL12 through its sole receptor CCR2, is critical for joint and growth plate development. In the present study, we examined the role of CCR2 in injury-induced-osteoarthritis (OA).

METHOD

We used a murine model of injury-induced-OA (destabilization of medial meniscus, DMM), and systemically blocked CCR2 using a specific antagonist (RS504393) at different times during disease progression. We examined joint degeneration by assessing cartilage (cartilage loss, chondrocyte hypertrophy, MMP-13 expression) and bone lesions (bone sclerosis, osteophytes formation) with or without the CCR2 antagonist. We also performed pain behavioral studies by assessing the weight distribution between the normal and arthritic hind paws using the IITS incapacitance meter.

RESULTS

Testing early vs delayed administration of the CCR2 antagonist demonstrated differential effects on joint damage. We found that OA changes in articular cartilage and bone were ameliorated by pharmacological CCR2 blockade, if given early in OA development: specifically, pharmacological targeting of CCR2 during the first 4 weeks (wks) following injury, reduced OA cartilage and bone damage, with less effectiveness with later treatments. Importantly, our pain-related behavioral studies showed that blockade of CCR2 signaling during early, 1-4 wks post-surgery or moderate, 4-8 wks post-surgery, OA was sufficient to decrease pain measures, with sustained improvement at later stages, after treatment was stopped.

CONCLUSIONS

Our data highlight the potential efficacy of antagonizing CCR2 at early stages to slow the progression of post-injury OA and, in addition, improve pain symptoms.

Prevalence of Bilateral Involvement in Patients with Discoid Lateral Meniscus : a Systematic Literature Review

We assessed the prevalence of bilateral discoid lateral meniscus (BDLM), as well as its subtypes, among patients with symptomatic DLM. Medline, Cochrane, EMBASE, and Google Scholar were searched until September 18, 2015. All studies evaluating patients with BDLM who underwent MRI, macroscopic observation, and/or arthroscopy for the diagnosis of discoid meniscus/menisci were included. Eight clinical studies with a total of 583 DLM patients examined including 103 cadavers. There was a male predominance and average age of BDLM patients ranged from 10.4 to 39.9 years. The reported prevalence was higher in East Asian countries (72.7 to 97%) than rest of the world (6.8 to 90%). Homotypes were much more common than heterotype, and ranged from 82.9 to 91.7% of all BDLM patients. The actual prevalence of BDLM is likely higher. The findings provide a glimpse of the wide spread this disorder potentially has in East Asia.

MR imaging of displaced meniscal tears of the knee: Importance of a “disproportional posterior horn sign”

Purpose: Meniscal tears associated with displaced fragments are clinically significant. We propose the "disproportional posterior horn sign" as a supportive criterion to identify a posterocentrally displaced meniscal fragment on MR imaging studies. If the meniscal posterior horn in the central portion appears larger than that in the peripheral section, it is considered positive for "disproportional posterior horn sign".

Material and Methods: MR images obtained in 42 patients with 43 lesions, confirmed to have displaced meniscal tears, were included in this study. The MR images were retrospectively evaluated for the presence of the "disproportional posterior horn sign", as well as the other known signs.

Results: The "disproportional posterior horn sign" was seen in 9 (20.9%) of 43 lesions, including 1 lateral discoid meniscal tear, 5 lateral meniscal tears and 3 medial meniscal tears. Five of them also had other signs of a displaced meniscal fragment. However, the remaining 4 cases only exhibited the "disproportional posterior horn sign". For the other MR signs, the "absent bow tie sign" was detected in 40 (93%) of 43 lesions, the "flipped meniscus sign" in 27 (62.8%) of 43 lesions, the "double posterior cruciate ligament sign" in 17 (39.5%) of 43 lesions and the "notch fragment sign" in 22 (51.2%) of 43 lesions.

Conclusion: The "disproportional posterior horn sign" is helpful in demonstrating a posterocentrally displaced meniscal fragment, especially when other characteristic signs are unremarkable or absent.

Arthroscopic Decompression for a Giant Meniscal Cyst

The authors report the case of a giant medial meniscal cyst in an osteoarthritic knee of an 82-year-old woman that was successfully treated with only arthroscopic cyst decompression. The patient noticed a painful mass on the medial side of the right knee that had been gradually growing for 5 years. Magnetic resonance imaging showed an encapsulated large medial cystic mass measuring 80×65×40 mm that was adjacent to the medial meniscus. An accompanying horizontal tear was also detected in the middle and posterior segments of the meniscus. The medial meniscus was resected up to the capsular attachment to create bidirectional flow between the joint and the cyst with arthroscopic surgery. Magnetic resonance imaging performed 14 months postoperatively showed that the cyst had completely disappeared, and no recurrence was observed during a 2-year follow-up period. An excellent result could be obtained by performing limited meniscectomy to create a channel leading to the meniscal cyst, even though the cyst was large. Among previously reported cases of meniscal cysts, this case is the largest to be treated arthroscopically without open excision.

[CLINICAL AND ARTHROSCOPIC FINDINGS IN MENISCAL INJURY AND KNEE INSTABILITY: A PROSPECTIVE STUDY]

INTRODUCTION

Medical history and physical examination are expected to provide the basic knowledge allowing diagnosis of a disease and thus enabling to plan the course of treatment.

OBJECTIVE

This study aimed to examine this hypothesis by comparing pre-operative diagnosis of meniscal and anterior cruciate ligament (ACL) injuries to final surgical findings.

MATERIAL AND METHODS

We prospectively compared the pre-surgical diagnosis to the arthroscopic findings in 753 arthroscopic procedures.

RESULTS

Clinical diagnosis of a medial meniscal (MM) tear was proven by arthroscopy in 65% of cases. Clinical diagnosis of a lateral meniscal (LM) tear was proven by arthroscopy in 54% of cases. Clinical complaints of instability correlated with partial or complete ACL rupture in 85% of cases. The accuracy of the clinical examination concerning ACL integrity ranged from 86% to 90%. Lachman and Pivot tests were slightly superior to the Drawer test.

DISCUSSION

Arthroscopic surgery is the most common surgical procedure in orthopedics. The diagnosis, which is based on history and physical examination in most cases, allows proper management of the case and an appropriate treatment plan. In most scenarios, these operations are conducted based on the diagnosis and treatment performed before surgery. In this study we showed that even in experienced and skilled hands, a clinical diagnosis of meniscal tear was approved by arthroscopy in only 54% to 65% of cases. A clinical diagnosis of ACL injury was approved by arthroscopy, in 99% of cases.

CONCLUSION

When planning conservative treatment or surgical intervention for a knee injury, it should be kept in mind that the clinical diagnosis of ACL rupture is highly reliable, while the clinical diagnosis of meniscal injury is only moderately reliable. Thus, especially when planning surgical intervention, the utilization of further imaging would be desirable when isolated meniscal injury is suspected.

[THE EVOLUTION IN TREATING MENISCAL TEARS--FROM RESECTION TO SUTURING]

The meniscus has an important biomechanical role in the normal function of the knee including load bearing, shock absorption and joint stability. Tears of the meniscus are one of the common sports injuries. The knowledge that total meniscectomy causes early development of degenerative changes has raised the prevalence of meniscal tear repair in order to preserve as much as possible of the meniscal tissue. The type of tear (degenerative of traumatic), shape and location have a critical effect on healing ability after suture of the tear and thus will determine the treatment plan.

Surgical interventions for meniscal tears: a closer look at the evidence

INTRODUCTION

The aim of the present study was to compare the outcomes of various surgical treatments for meniscal injuries including (1) total and partial meniscectomy; (2) meniscectomy and meniscal repair; (3) meniscectomy and meniscal transplantation; (4) open and arthroscopic meniscectomy and (5) various different repair techniques.

MATERIALS AND METHODS

The Bone, Joint and Muscle Trauma Group Register, Cochrane Database, MEDLINE, EMBASE and CINAHL were searched for all (quasi) randomized controlled clinical trials comparing various surgical techniques for meniscal injuries. Primary outcomes of interest included patient-reported outcomes scores, return to pre-injury activity level, level of sports participation and persistence of pain using the visual analogue score. Where possible, data were pooled and a meta-analysis was performed.

RESULTS

A total of nine studies were included, involving a combined 904 subjects, 330 patients underwent a meniscal repair, 402 meniscectomy and 160 a collagen meniscal implant. The only surgical treatments that were compared in homogeneous fashion across more than one study were the arrow and inside-out technique, which showed no difference for re-tear or complication rate. Strong evidence-based recommendations regarding the other surgical treatments that were compared could not be made.

CONCLUSIONS

This meta-analysis illustrates the lack of level I evidence to guide the surgical management of meniscal tears.

LEVEL OF EVIDENCE

Level I meta-analysis.

Abnormal Mechanical Loading Induces Cartilage Degeneration by Accelerating Meniscus Hypertrophy and Mineralization After ACL Injuries In Vivo

BACKGROUND

Although patients with an anterior cruciate ligament (ACL) injury have a high risk of developing posttraumatic osteoarthritis (PTOA), the role of meniscus hypertrophy and mineralization in PTOA after an ACL injury remains unknown.

PURPOSE/HYPOTHESIS

The purpose of this study was to determine if menisci respond to abnormal loading and if an ACL injury results in meniscus hypertrophy and calcification. The hypotheses were that (1) abnormal mechanical loading after an ACL injury induces meniscus hypertrophy and mineralization, which correlates to articular cartilage damage in vivo, and (2) abnormal mechanical loading on bovine meniscus explants induces the overexpression of hypertrophic and mineralization markers in vitro.

STUDY DESIGN

Controlled laboratory study.

METHODS

In vivo guinea pig study (hypothesis 1): Three-month-old male Hartley guinea pigs (n = 9) underwent ACL transection (ACLT) on the right knee; the left knee served as the control. Calcification in the menisci was evaluated by calcein labeling 1 and 5 days before knee harvesting at 5.5 months. Cartilage and meniscus damage and mineralization were quantified by the Osteoarthritis Research Society International score and meniscus grade, respectively. Indian hedgehog (Ihh), matrix metalloproteinase-13 (MMP-13), collagen type X (Col X), progressive ankylosis homolog (ANKH), ectonucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1), alkaline phosphatase (ALP), inorganic pyrophosphate (PPi), and inorganic phosphate (Pi) concentrations were evaluated by immunohistochemistry and enzyme-linked immunosorbent assay. In vitro bovine meniscus explant study (hypothesis 2): Bovine meniscus explants were subjected to 25% strain at 0.3 Hz for 1, 2, and 3 hours. Cell viability was determined using live/dead staining. The levels of mRNA expression and protein levels were measured using real-time quantitative reverse transcription polymerase chain reaction and Western blot after 24, 48, and 72 hours in culture. The conditioned medium was collected for sulfated glycosaminoglycan (GAG) release and Pi/PPi assay.

RESULTS

In vivo guinea pig study: Meniscus size and area as well as intensity of meniscus calcification were significantly increased in the ACLT group compared with the control group. Both calcified area and intensity were correlated with cartilage damage in the ACLT group (meniscus calcified area: r = 0.925, P < .0001; meniscus calcified intensity: r = 0.944, P < .0001). Ihh, MMP-13, Col X, ANKH, ENPP1, and ALP expression were increased in the ACLT group compared with the control group. The Pi level and Pi/PPi ratio increased by 63% and 42%, respectively, in the ACLT group compared with the control group. In vitro bovine meniscus explant study: Cell death was found in the superficial zone of the bovine meniscus explants after loading for 3 hours. The mRNA expression and protein levels of MMP-13, ANKH, ENPP1, and ALP were up-regulated in all 3-hour loaded samples. The Pi/PPi ratio and sulfated GAG content in the culture medium were increased in the 3-hour loaded group.

CONCLUSION

Meniscus hypertrophy and mineralization correlated to cartilage degeneration after ACL injuries.

CLINICAL RELEVANCE

The study data suggest that the suppression of meniscus hypertrophy and calcification may decrease the risk of PTOA after ACL injuries.

Epidemiology of meniscal injuries in US high school athletes between 2007 and 2013

PURPOSE

Knowledge of epidemiologic trends of meniscal injuries in young active populations is limited. Better awareness of injury patterns is a first step to lowering injury rates. Our hypothesis was that meniscal injuries in high school athletes would vary by gender, sport, and type of exposure.

METHODS

During the 2007/2008 and 2012/2013 academic years, a large nationally disperse sample of US high schools reported athlete exposure and injury data for 22 sports by having certified athletic trainers complete an internet-based data collection tool.

RESULTS

One thousand and eighty-two meniscal injuries were reported during 21,088,365 athlete exposures for an overall injury rate of 5.1 per 100,000 athlete exposures. The overall rate of injury was higher in competition (11.9) than practice (2.7) (RR = 4.4; 95% CI 3.9-5.0), and 12/19 sports showed significantly higher injury rates in competition compared to practice. Of all injuries, 68.0% occurred in boys, yet among the gender-comparable sports of soccer, basketball, track and field, lacrosse, and baseball/softball injury rates were higher for girls than boys (5.5 and 2.5, respectively, RR = 2.2; 95% CI 1.8-2.7). Contact injury represented the most common mechanism (55.9%). Surgery was performed for the majority of injuries (63.8%), and 54.0% of athletes had associated intra-articular knee pathology.

CONCLUSIONS

Meniscal injury patterns among high school athletes vary by gender, sport, and type of exposure. Our study is clinically relevant because recognition of distinct differences in these injury patterns will help drive evidence-based, targeted injury prevention strategies and efforts.

LEVEL OF EVIDENCE

III.

Meniscal Root Tears: Identification and Repair

Intact menisci are capable of converting the axial load of tibiofemoral contact into hoop stress that protects the knee joint. Total meniscectomy leads to rapid degeneration of the knee. Strong clinical and biomechanical data show meniscal root tears and avulsions are the functional equivalent of total meniscectomy. Lateral root tears commonly occur with knee ligament sprains and tears. Medial root tears are generally more chronic, and can be caused by preexisting knee arthritis. Meniscal root repair is indicated when there is identification of a meniscal root tear in a knee with minimal to no arthritis. Chronic root tears in the setting of osteoarthritis are treated conservatively. Meniscal root tears can acutely occur with cruciate ligament tears, can exaggerate symptoms of instability, and will have negative ramifications on outcomes of anterior cruciate ligament reconstruction if not addressed concomitantly. In this review, we describe the importance of the menisci for knee joint longevity through anatomy and biomechanics, the diagnostic workup, and ultimately a transosseous technique for repair of meniscal root tears and avulsions.

[Analysis on treatment and diagnosis of Segond fracture combined with injuries]

OBJECTIVE

To investigate the clinical characteristics of Segond fracture combined with injuries, and to explore the operative method and opportunity.

METHODS

From June 2010 to December 2014, 10 patients with Segond fracture were treated. There were 10 males, ranging in age from 26 to 69 years old, with a mean of 42 years old. Under arthroscopy examination within 7 to 10 days after injury, 6 patients had compete rupture of anterior cruciate ligament and meniscus injury; 2 patients had tibial avulsion fractures of the ACL combined with meniscus injury. At 4 to 8 weeks after injury, 2 patients were performed with arthroscopy examination; 1 patient had complete rupture of anterior and posterior cruciate ligament combined with meniscus injury; and the other patient had complete rupture of anterior cruciate ligament alone. All the patients with cruciate ligament rupture were treated with reconstruction of cruciate ligament; 9 patients had meniscus injuries were treated with menisus plasty or suture; and 2 patients had tibial avulsion fractures of the ACL were treated with non-absorbable Ethicon suture fixation under arthroscopy. After operation, the Lysholm scoring system was used to evaluate clinical effects.

RESULTS

Eight patients were operated within 10 days after injury, the knee joints swelling was obvious at the 3rd day after operation, and blood oozing was found by joint puncture. These 8 patients did out-of-bed activity with assistance at 1 week postoperatively. Other 2 patients performed operation in 4 to 8 weeks after injury without knee joint obvious swelling at the 3rd day after operation, and no blood oozing was found by joint puncture. These 2 patients did out-of-bed activity with assistance after 3 days postoperatively. All the patients were followed up, and the duration ranged from 12 to 24 months, with an average of 18 months. Postoperative Lysholm score of all patients was higher than preoperative scor, and the results were satisfactory.

CONCLUSION

For Segond fractures, firstly, it is important to gain early diagnosis for treatment. Secondly, it is often associated with the rupture of anterior cruciate ligament and meniscus injuries, and the best time of cruciate ligament rebuilding and meniscus repairing maybe between 4 to 8 weeks after injury. Thirdly, personalized treatment should be chosen according to different complications.

Medial Meniscal Root Avulsion: A Biomechanical Comparison of 4 Different Repair Constructs

PURPOSE

To evaluate the time-zero load-to-failure strength of 4 different constructs used to repair medial meniscal root avulsions.

METHODS

Sixty fresh-frozen cadaveric knees with a mean age of 74 years were used for this study. Each knee was dissected to isolate the attachment of the posterior root of the medial meniscus to the tibial plateau. An Instron machine (Instron, Norwood, MA) with a custom-designed clamp was used to avulse the intact posterior meniscal root in 12 control specimens. An additional 48 specimens were tested after transection of the native meniscal root to evaluate the pullout strength of 4 different repair constructs using No. 0 FiberWire suture (Arthrex, Naples, FL): a single suture (n = 12), a double suture (n = 12), a loop stitch (n = 12), and a locking loop stitch (n = 12). Analysis of variance was used to compare load to failure and stiffness of all 4 groups; pair-wise, between-group differences were also assessed.

RESULTS

Repair failure occurred most commonly by suture pullout in 94% of the specimens in the repair groups. For the controls, failure occurred most commonly at the meniscus-clamp interface. Failure load was highest for the control group (mean, 359.5 ± 168 N), followed in descending order by the locking loop stitch (191.4 ± 45.1 N), loop stitch (119.6 ± 55.0 N), double suture (96.2 ± 51.4 N), and single suture (58.2 ± 29.6 N). The control group was significantly stronger than 3 of the experimental groups (single suture [95% CI, 3.8 to 11.3], double suture [95% CI, 2.1 to 6.4], and loop stitch [95% CI, 2.0 to 4.5]; P < .0001) but not the locking loop stitch (P = .003; 95% CI, 1.2 to 3.2). The locking loop stitch was significantly stronger than the single suture (P < .0001; 95% CI, 2.0 to 5.4) and double suture (P = .003; 95% CI, 1.2 to 2.9). The locking loop stitch was significantly stiffer than the single suture (P < .0001; 95% CI, 3.8 to 20.3), double suture (P < .0001; 95% CI, 2.0 to 9.8), and loop stitch (P = .03; 95% CI, 1.1 to 5.5) but not significantly different from the control group (P = .93; 95% CI, 0.3 to 1.9). Age and gender had no effect on pullout strength.

CONCLUSIONS

The results of this study show that the locking loop stitch provided time-zero load-to-failure strength that most closely approximated the strength of the native meniscal root in addition to being significantly stronger and stiffer than 3 other commonly used repair methods. The true strength of the native meniscal root is unknown based on limitations with our testing methodology.

CLINICAL RELEVANCE

The locking loop stitch exhibited the highest load to failure and stiffness of the 4 fixation methods tested, despite the fact that none of the fixation methods replicated the strength of the intact meniscal root. It is currently unknown what strength of fixation is required for healing of meniscal root repairs.

Clinical results following meniscal sutures: does concomitant acl repair make a difference?

INTRODUCTION

The purpose of this study is to analyze the clinical results of meniscal tears repaired with an all-inside suture with special attention to the results in stable versus anterior cruciate ligament (ACL)-deficient knees.

METHODS

We studied 45 meniscal tears (32 medial, 13 lateral) repaired in 43 patients using a single all-inside suture system. The patients were divided in two groups and followed-up for at least 12 months. Group A (stable knees with isolated meniscal tears) consisted of 19 patients treated with all-inside sutures. Group B (ACL-deficient knees with meniscal tears) consisted of 24 patients treated with ACL reconstruction together with the meniscal repair. All the meniscal tears were located in red/red (35) or red/white (10) zone. Criteria for clinical success included absence of joint-line tenderness, locking, swelling, and a negative McMurray test. Preoperative and postoperative clinical evaluation also included the Tegner and Lysholm knee scores.

RESULTS

The clinical success rate of the repairs was 86%. According to our criteria, six of 43 repaired menisci (14%) were considered failures. Mean Lysholm scores improved significantly in both groups (58 to 88.20) and the improvement was significantly greater in group B (From 54.47 to 88, p > 0.05). Twenty patients (83.3%) had an excellent or good result in group B and sixteen (84%) in group A, according to the Lysholm knee score.

CONCLUSION

Our clinical results show that arthroscopic meniscal repair with all-inside devices provided a high rate of meniscus healing and seem to be safe and effective, for isolated meniscal tears as well as for ACL-deficient knees with meniscal tears. Final functional scores were similar for ACL-competent and ACL-deficient knees.