Medial Meniscus Posterior Root Tears Lead to Changes in Joint Contact Mechanics at Low Flexion Angles During Simulated Gait

BACKGROUND

Previous biomechanical studies evaluating medial meniscus posterior root tears (MMPRTs) are limited to low loads applied at specified loading angles, which cannot capture the effects of MMPRTs during the multidirectional forces and moments placed across the knee during physiological activities.

PURPOSE

To quantify the effects of MMPRTs on knee joint contact mechanics during simulated gait.

STUDY DESIGN

Controlled laboratory study.

METHODS

Six human cadaveric knees were mounted on a robotic simulator programmed to apply dynamic forces, moments, and flexion angles to mimic level walking. Twelve cycles of multidirectional and dynamic standard gait input waveforms, normalized to specimen-specific body weight, were applied to the following conditions: (1) native, intact meniscus and (2) MMPRT. Peak contact stress, contact area, and the position of the weighted center of contact across the medial tibial plateau throughout the stance phase of gait were quantified using an electronic sensor placed across the medial tibial plateau. The difference between the intact state and MMPRT condition was calculated for each metric, and then the means and 95% CIs were computed.

RESULTS

Despite heterogeneity in knee contact forces, MMPRTs significantly increased peak contact stress by a mean of 2 MPa across 20% to 37% of the simulated gait cycle and significantly decreased the contact area by a mean of 200 mm2 across 16% to 60% of the simulated gait cycle in comparison with the native state. There was no significant difference in the position of the weighted center of contact, in either the anterior-posterior or medial-lateral directions, after MMPRT.

CONCLUSION

MMPRTs led to both a significant increase in peak contact stress and decreased contact areas for a portion of the simulated gait cycle ranging from 20% to 37% of gait, during which time the femur was flexed <15°.

CLINICAL RELEVANCE

Contact mechanics are significantly affected after MMPRTs during early to midstance and at knee flexion angles lower than demonstrated previously. These data provide further biomechanical justification for treating MMPRTs.

Acute Repair of Meniscus Root Tear Partially Restores Joint Displacements as Measured With Magnetic Resonance Images and Loading in a Cadaveric Porcine Knee

The meniscus serves important load-bearing functions and protects the underlying articular cartilage. Unfortunately, meniscus tears are common and impair the ability of the meniscus to distribute loads, increasing the risk of developing osteoarthritis. Therefore, surgical repair of the meniscus is a frequently performed procedure; however, repair does not always prevent osteoarthritis. This is hypothesized to be due to altered joint loading post-injury and repair, where the functional deficit of the meniscus prevents it from performing its role of distributing forces. The objective of this study was to quantify joint kinematics in an intact joint, after a meniscus root tear, and after suture repair in cadaveric porcine knees, a frequently used in vivo model. We utilized an magnetic resonance images-compatible loading device and novel use of a T1 vibe sequence to measure meniscus and femur displacements under physiological axial loads. We found that anterior root tear led to large meniscus displacements under physiological axial loading and that suture anchor repair reduced these displacements but did not fully restore intact joint kinematics. After tear and repair, the anterior region of the meniscus moved posteriorly and medially as it was forced out of the joint space under loading, while the posterior region had small displacements as the posterior attachment acted as a hinge about which the meniscus pivoted in the axial plane. Methods from this study can be applied to assess altered joint kinematics following human knee injuries and evaluate repair strategies aimed to restore joint kinematics.

Frequency of anterolateral ligament tears and ramp lesions in patients with anterior cruciate ligament tears and associated injuries indicative for these lesions-a retrospective MRI analysis

OBJECTIVES

To assess the frequency of anterolateral ligament (ALL) tears and ramp lesions (RL) detected with MRI in patients with anterior cruciate ligament (ACL) tears and to describe associated injuries indicative for these lesions.

METHODS

In this retrospective study, 164 patients with surgically verified ACL tears were included. Preoperative MRI scans were reviewed for ALL tears and different types of RL. All coexisting meniscal tears, tears of the medial (MCL) and lateral collateral band (LCL), and posterior-medial tibial bone marrow edema (BME) were recorded. The frequency of ALL tears and RL was assessed and coexisting injuries were correlated using Pearson's chi-square test. A p < 0.05 was defined as statistically significant. In cases of multiple testing, Bonferroni's correction was applied.

RESULTS

ALL tears and RL combined were detected in 28 patients (17.1%), ALL tears in 48 patients (29.3%), and RL in 54 patients (32.9%) which were significantly associated to each other. ALL tears were significantly associated with tears of the posterior horn of the lateral meniscus (PHLM), BME, and with tears of the LCL and MCL. RL were significantly associated with tears of the posterior horn of the medial (PHMM) and PHLM, with BME, and with tears of the LCL.

CONCLUSIONS

ACL tears are associated with RL or ALL tears in about one-third of cases and with both lesions combined in about one-fifth of cases. ALL tears and RL are significantly associated with additional posttraumatic injuries, which can thus be indicative of these lesions.

KEY POINTS

• ACL tears were associated with ramp lesions or ALL tears in about one-third of the cases. • Ramp lesions and ALL tears were significantly associated with each other, tear in the PHLM, tear in the LCL, and BME. • ALL tears were more frequently associated with instable classified ramp lesion type 4b and type 5.

In vitro method to quantify and visualize mechanical wear in human meniscus subjected to joint loading

The mechanical wear and tear of soft connective tissue from repetitive joint loading is a primary factor in degenerative joint disease, and therefore methods are needed to accurately characterize wear in joint structures. Here, we evaluate the accuracy of using a structured light 3D optical scanning system and modeling software to quantify and visualize volume loss in whole human meniscus subjected to in vitro joint loading. Using 3D printed meniscus replicas with known wear volumes, we determined that this novel imaging method has a mean accuracy of approximately 13 mm3, corresponding to a mean error of less than 7% when measuring meniscal volumetric changes of 0.2 cm3 (size of a pea). The imaging method was then applied to measure the in vitro wear of whole human menisci at four time points when a single cadaveric knee was subjected to one million cycles of controlled joint loading. The medial and lateral menisci reached steady state volumetric reductions of 0.72 cm3 and 0.34 cm3 per million cycles, respectively. Colorimetric maps of linear wear depth revealed high wear and deformation in the posterior regions of both the medial and lateral menisci. For the first time, this study has developed a method to accurately characterize volume loss in whole meniscus subjected to in vitro joint loading. This 3D scanning method offers researchers a new investigative tool to study mechanical wear and joint degeneration in meniscus, and other soft connective tissues.

Injury Prevention Effect of MRI Imaging Technology in Physical Education and Sports Training

In order to solve the problem of observing and analyzing the clinical value of MRI diagnosis in patients with knee sports injury and guiding clinical targeted treatment, the author proposed a sports injury prevention method in sports training teaching based on MRI image observation. This method retrospectively analyzed the imaging data of 101 patients with knee joint MRI examination due to osteoarthritis, sports injury and synovitis in joint surgery, and arthroscopic exclusion of true meniscus tear, MR multisequence and multiplane scans were performed to observe the anatomical features of TGL and MFL images and the occurrence rate of the lateral meniscus "false tear sign," and the χ ² test was used to compare the occurrence rate of "pseudo-tear sign" between genders and sides. Experimental results show that the incidence of TGL on MRI was about 67.3% (68/101), and the incidence of "pseudo-tear sign" in the anterior horn of the lateral meniscus caused by TGL was 2.9% (2/68). The overall appearance rate of MFL on MRI was 91.1% (92/101), the appearance rate of plate anterior ligament (HL) was 13.9% (14/101), and the occurrence rate of "pseudo-tear sign" in the posterior horn of the lateral meniscus caused by HL was 7.1% (1/14). The occurrence rate of the posterior ligament (WL) was 77.2% (78/101), and the incidence of "pseudo-tear sign" in the posterior horn was 20.5% (16/78). According to the shape and course of TGL and MFL on MRI, and the direction and position of the lateral meniscus pseudotear, combined with MRI sagittal plane and coronal plane observation, it can effectively identify the true and false attributes of lateral meniscus anterior and posterior horn tears, thereby reducing unnecessary surgical treatment.

Steep posterior lateral tibial slope, bone contusion on lateral compartments and combined medial collateral ligament injury are associated with the increased risk of lateral meniscal tear

PURPOSE

To determine the risk factors for lateral meniscus and root tears in patients with acute anterior cruciate ligament (ACL) injuries.

METHODS

A total of 226 patients undergoing acute ACL reconstruction were included in the study sample. Exclusion criteria were revisions, fractures, chronic cases, and multiple ligament injuries, with the exception of medial collateral ligament (MCL) injuries. The patients were divided into groups based on the presence of lateral meniscus and root tears by arthroscopy. Binary logistic regression was used to analyze risk factors including age, sex, body mass index (BMI), injury mechanism (contact/non-contact), Segond fracture, side-to-side laxity, location of bone contusion, medial and lateral tibial and meniscal slope, mechanical axis angle, and grade of pivot shift.

RESULTS

Overall lateral meniscus (LM) tears were identified in 97 patients (42.9%), and LM root tears were found in 22 patients (9.7%). The risk of an LM tear in ACL-injured knees increased with bone contusion on LTP (odds ratio [OR], 3.5; 95% confidence interval [CI] 1.419-8.634; P = 0.007), steeper lateral tibial slope (OR, 1.133; 95% CI 1.003-1.28; P = 0.045), MCL injury (OR, 2.618; 95% CI 1.444-4.746; P = 0.002), and non-contact injury mechanism (OR, 3.132; 95% CI 1.446-6.785; P = 0.004) in logistic regression analysis. The risk of LM root tear in ACL-injured knees increased with high-grade pivot shift (OR, 9.127; 95% CI 2.821-29.525; P = 0.000) and steeper lateral tibial slope (OR, 1.293; 95% CI 1.061-1.576; P = 0.011).

CONCLUSION

The increased risk of LM lesions in acute ACL-injured knees should be considered if significant risk factors including bone contusion on lateral compartments, MCL injury, and a steeper lateral tibial slope are present. Moreover, high-grade rotational injury with steeper lateral tibial slope are also significant risk factors for LM root tears, and therefore care should be taken by clinicians not to miss such lesions.

LEVEL OF EVIDENCE

III.

Performing a knee arthroscopy among patients with degenerative knee disease: one-third is potentially low value care

PURPOSE

The purpose of this study was to assess in which proportion of patients with degenerative knee disease aged 50+ in whom a knee arthroscopy is performed, no valid surgical indication is reported in medical records, and to explore possible explanatory factors.

METHODS

A retrospective study was conducted using administrative data from January to December 2016 in 13 orthopedic centers in the Netherlands. Medical records were selected from a random sample of 538 patients aged 50+ with degenerative knee disease in whom arthroscopy was performed, and reviewed on reported indications for the performed knee arthroscopy. Valid surgical indications were predefined based on clinical national guidelines and expert opinion (e.g., truly locked knee). A knee arthroscopy without a reported valid indication was considered potentially low value care. Multivariate logistic regression analysis was performed to assess whether age, diagnosis ("Arthrosis" versus "Meniscal lesion"), and type of care trajectory (initial or follow-up) were associated with performing a potentially low value knee arthroscopy.

RESULTS

Of 26,991 patients with degenerative knee disease, 2556 (9.5%) underwent an arthroscopy in one of the participating orthopedic centers. Of 538 patients in whom an arthroscopy was performed, 65.1% had a valid indication reported in the medical record and 34.9% without a reported valid indication. From the patients without a valid indication, a joint patient-provider decision or patient request was reported as the main reason. Neither age [OR 1.013 (95% CI 0.984-1.043)], diagnosis [OR 0.998 (95% CI 0.886-1.124)] or type of care trajectory [OR 0.989 (95% CI 0.948-1.032)] were significantly associated with performing a potentially low value knee arthroscopy.

CONCLUSIONS

In a random sample of knee arthroscopies performed in 13 orthopedic centers in 2016, 65% had valid indications reported in the medical records but 35% were performed without a reported valid indication and, therefore, potentially low value care. Patient and/or surgeons preference may play a large role in the decision to perform an arthroscopy without a valid indication. Therefore, interventions should be developed to increase adherence to clinical guidelines by surgeons that target invalid indications for a knee arthroscopy to improve care.

LEVEL OF EVIDENCE

IV.

Artificial Intelligence in Repairing Meniscus Injury in Football Sports with Perovskite Nanobiomaterials

Knee meniscus injuries are more likely to occur in young adults in clinical practice, and their lower age of onset and greater impact on joint function after injury also put forward higher requirements for the treatment and rehabilitation of meniscus injuries. With the rapid development of artificial intelligence technology and arthroscopic minimally invasive technology, arthroscopic meniscus plasty and perovskite nanobiomaterial repair have gradually replaced the previous open meniscus surgery of the knee joint and has become the main method of meniscus injury treatment, and the perovskite nanobiomaterial repair technique that incorporates artificial intelligence technology is also gradually being applied. Therefore, this article studies the role of perovskite nanobiomaterials in the repair of meniscus injuries in football sports and analyzes the biological characteristics of the inner and outer meniscus to provide help to improve the healing rate of meniscus injuries. The study selected six male meniscus-injured patients (meniscus injuries caused by football sports) and obtained six injured menisci. The same cross section of the same part of the meniscus was analyzed inside and outside the meniscus. At the same time, a meniscal injury step was performed on the patient. The biological characteristics of perovskite nano-biomaterials in the repair of meniscus injuries in football sports were compared and analyzed, and the patient's gait before and after surgery was also compared. Experiments have shown that the percentage of the postoperative support phase of the affected limb is significantly higher than that before surgery (P < 0.05), the percentage of the postoperative support phase and flatfoot phase decreased compared with that before surgery, and the gait cycle parameters of both lower extremities improved after surgery, obviously (P < 0.05). It explains that the arthroscopic repair of perovskite nanobiomaterials combined with the artificial intelligence technology to repair the meniscus anterior angle injury is simple and does not require special equipment, has fewer complications, is safe and reliable, and has a high clinical healing rate and a high patient satisfaction rate after surgery. The curative effect is significant; artificial intelligence technology and the application of perovskite nanobiomaterials provide more possibilities for meniscus repair.

Vibration Stimulation as a Non-Invasive Approach to Monitor the Severity of Meniscus Tears

Musculoskeletal disorders and injuries are one of the most prevalent medical conditions across age groups. Due to a high load-bearing function, the knee is particularly susceptible to injuries such as meniscus tears. Imaging techniques are commonly used to assess meniscus injuries, though this approach suffers from limitations including high cost, need for skilled personnel, and confinement to laboratory or clinical settings. Vibration-based structural monitoring methods in the form of acoustic emission analysis and vibration stimulation have the potential to address the limits associated with current diagnostic technologies. In this study, an active vibration measurement technique is employed to investigate the presence and severity of meniscus tear in cadaver limbs. In a highly controlled ex vivo experimental design, a series of cadaver knees (n =6) were evaluated under an external vibration, and the frequency response of the joint was analyzed to differentiate the intact and affected samples. Four stages of knee integrity were considered: baseline, sham surgery, meniscus tear, and meniscectomy. Analyzing the frequency response of injured legs showed significant changes compared to the baseline and sham stages at selected frequency bandwidths. Furthermore, a qualitative analytical model of the knee was developed based on the Euler-Bernoulli beam theory representing the meniscus tear as a change in the local stiffness of the system. Similar trends in frequency response modulation were observed in the experimental results and analytical model. These findings serve as a foundation for further development of wearable devices for detection and grading of meniscus tear and for improving our understanding of the physiological effects of injuries on the vibration characteristics of the knee. Such systems can also aid in quantifying rehabilitation progress following reconstructive surgery and / or during physical therapy.

What's New in the Management of Pediatric Anterior Cruciate Ligament Tears and Tibial Spine Fractures

As the number of pediatric and adolescent patients participating in sports continues to increase, so too does the incidence of anterior cruciate ligament (ACL) tears in this population. There is increasing research on pediatric and adolescent ACL tears; hundreds of articles on the topic have been published in the past few years alone. It is important to highlight the most pertinent information in the past decade. In discussing pediatric ACL tears, it is also important to review tibial spine fractures. These injuries are rightfully grouped together because tibial spine fractures often occur with a mechanism of injury similar to that of ACL tears, but typically in a younger age group. Because management is different, understanding the similarities and differences between the two pathologies is important. Recent updates on the epidemiology, diagnosis, management, and outcomes of both pediatric ACL tears and tibial spine fractures need to be reviewed.

Medial meniscal ossicles: Associated knee MRI findings in a multicenter case-control study

PURPOSE

The purpose of this study was to assess and compare the prevalence of meniscal, ligament and cartilage lesions on knee MRI in a series of age- and sex-matched patients with and without medial meniscal ossicle.

MATERIALS AND METHODS

Forty-two knee MRI examinations obtained in 42 patients (36 men, 6 women; mean age, 42.5±22.2 [SD] years; range: 19-65years) on which a medial meniscal ossicle was present were compared to 42 knee MRI examinations obtained in 42 age- and sex-matched patients (36 men, 6 women; mean age, 41.8±20.6 [SD] years; range: 19-65years) on which no medial meniscal ossicles were present. Two radiologists (R1, R2) blinded to the presence of meniscal ossicle by reading only the fat-saturated intermediate-weighted MR images separately assessed the presence of meniscal, ligament and cartilage lesions on these 84 knee MRI examinations. Prevalence of meniscal and ligament lesions and degree of cartilage degradation at MRI were compared between knees with and those without medial meniscal ossicle.

RESULTS

In knees with medial meniscal ossicle, R1 and R2 detected 33 (79%) and 38 (90%) medial meniscal lesions, respectively that involved the posterior root (n=25/32 for R1/R2), the posterior horn (n=19/14 for R1/R2) or the body (n=8/10 for R1/R2). The prevalence of posterior root tear (60% [25/42]/76% [32/42] for R1/R2) and that of anterior cruciate ligament (ACL) lesions (48% [20/42]/57% [24/42] for R1/R2) as well as the medial cartilage degradation score (3.35±0.87 [SD] for R1 and 3.92±0.78 [SD] for R2) were significantly greater in knees with than in knees without medial meniscal ossicle (root lesions: P<0.01 for both readers; ACL lesions and medial cartilage score: P<0.01 for both readers).

CONCLUSION

On MRI examination, knees with a medial meniscal ossicle demonstrate a greater frequency of medial posterior root tear and of ACL lesions and a greater degree of medial femoro-tibial cartilage degradation by comparison with knees without medial ossicle.

Leukocyte-dependent effects of platelet-rich plasma on cartilage loss and thermal hyperalgesia in a mouse model of post-traumatic osteoarthritis

OBJECTIVE

Platelet-rich plasma (PRP) is an emerging therapeutic strategy for treatment of osteoarthritis (OA); however, there is a lack of preclinical and clinical evidence for its efficacy and its mechanism of action is unclear. In the current study, we utilized leukocyte poor-PRP (LP-PRP) and leukocyte rich-PRP (LR-PRP) to mimic clinical point of care formulations and assessed their potential to alter disease progression in a mouse model of post-traumatic OA.

METHOD

Three-month-old wild-type male FVB/N mice received destabilization of the medial meniscus (DMM) surgery to induce OA. To assess the efficacy of LP-PRP and LR-PRP, mice were given intraarticular injections at 2-, 7- and 28-days post-surgery. Mice were then assessed at 5-, 9-, and 13-weeks post-surgery for changes in chronic pain using the hot plate nociceptive assay. At 14-weeks, OA pathogenesis was evaluated using histology and phase-contrast μCT.

RESULTS

Treatment with LP-PRP and to a lesser extent LR-PRP preserved cartilage volume and surface area compared to phosphate-buffered saline (PBS) as measured by phase-contrast μCT. However, both treatments had higher Osteoarthritis Research Society International (OARSI) and synovitis scores compared to sham, and neither substantially improved scores compared to PBS controls. With respect to thermal hyperalgesia, PBS-treated mice displayed reduced latency to response compared to sham, and LR-PRP but not LP-PRP improved latency to response at 5-, 9- and 13-weeks post-surgery compared to PBS.

CONCLUSION

The results of this study suggest that effects of PRP therapy on OA progression and disease-induced hyperalgesia may be leukocyte-dependent. And while LP-PRP and to a lesser extent LR-PRP protect from volume and surface loss, significant pathology is still seen within OA joints. Future work is needed to understand how the different components of PRP effect OA pathogenesis and pain, and how these could be modified to achieve greater therapeutic efficacy.

TAT-Beclin-1 induces severe synovial hyperplasia and does not protect from injury-induced osteoarthritis in mice

OBJECT

Autophagy maintains cartilage homeostasis and is compromised during osteoarthritis (OA), contributing to cartilage degeneration. We sought to determine if D-isomer TAT-Beclin-1, a potent inducer of autophagy, could attenuate post-traumatic OA in mice.

METHODS

10-week-old mice underwent destabilization of the medial meniscus (DMM) surgery to induce post-traumatic OA, or sham surgery (control), and injected intra-articularly with D-isomer TAT-Beclin-1 (0.5-2 mg/kg) or PBS 1 week post-surgery for up to 9 weeks. Mice were sacrificed at 2 or 10 weeks post-surgery. Knee joint sections were evaluated by histopathology for cartilage degeneration and synovitis, and immunostaining for key markers of autophagy (LC3B), cell proliferation (nuclear Ki67), activated fibroblasts (αSMA), and cells of hematopoietic origin (CD45).

RESULTS

All D-isomer TAT-Beclin-1-treated DMM mice had no difference in the degree of cartilage degeneration compared to PBS-injected DMM mice. Surprisingly, all D-isomer TAT-Beclin-1-treated mice exhibited substantial synovial hyperplasia, with increased cellularity and ECM deposition (fibrosis-like phenotype), as compared to PBS-injected mice. Synovial effects of D-isomer TAT-Beclin-1 were dose- and injection frequency-dependent. An increased percentage of cells positive for LC3B and nuclear Ki67 were found in the synovial intima early after injection, which persisted after frequent injections.

CONCLUSIONS

D-isomer TAT-Beclin-1 did not attenuate cartilage degeneration, but rather induced synovial hyperplasia associated with increased expression of key markers of autophagy and cell proliferation and a fibrosis-like phenotype, independent of markers of fibroblast activation or persistent hematopoietic-origin cell infiltration. These data suggest that, if not tissue-targeted, caution should be taken using autophagy activators due to diverse cellular responses in the joint.

Clinical anatomy of the meniscus in animal models: pros and cons

Nowadays, despite the possibility to use in vitro or computer models in research, animal models are still essential. Different animal models are available for meniscal repair investigation. Although a unique perfect model for the structure of the human's knee does not exist, the choice of the proper animal model is crucial for a correct research. The principal animal models in the meniscal repair are sheep, goats, pigs and dogs. Each of these has pros and cons for their utilization. Analysing each pro and con is essential for optimizing the choice of the animal model, which depends on the experimental question, avoiding unnecessary waste of resources and minimizing the animal suffering, according to the Russell and Burch's three "Rs" principles (Reduce, Refine and Recycle). In this concise review, we resume the meniscus anatomical features of the main large animals, to help choose the most suitable animal model for subsequent studies on meniscal repair.

All-Inside Arthroscopic Meniscal Repair with the Arthrex Meniscal Cinch™ II

Meniscal tears are the most common indication for knee surgery. An appreciation of the limitations associated with the gold-standard inside-out meniscal repair technique has resulted in the development of newer all-inside techniques that overcome many of these issues. This paper describes, with a video illustration available online, a one-handed all-inside meniscal repair technique using the Meniscal Cinch™ II (Arthrex, Inc., Naples, FL).

The implications of non-anatomical positioning of a meniscus prosthesis on predicted human knee joint biomechanics

Despite all the efforts to optimize the meniscus prosthesis system (geometry, material, and fixation type), the success of the prosthesis in clinical practice will depend on surgical factors such as intra-operative positioning of the prosthesis. In this study, the aim was therefore to assess the implications of positional changes of the medial meniscus prosthesis for knee biomechanics. A detailed validated finite element (FE) model of human intact and meniscal implanted knees was developed based on a series of in vitro experiments. Different non-anatomical prosthesis positions were applied in the FE model, and the biomechanical response during the gait stance phase compared with an anatomically positioned prosthesis, as well as meniscectomized and also the intact knee model. The results showed that an anatomical positioning of the medial meniscus prosthesis could better recover the intact knee biomechanics, while a non-anatomical positioning of the prosthesis to a limited extent alters the knee kinematics and articular contact pressure and increases the implantation failure risk. The outcomes indicate that a medial or anterior positioning of the meniscus prosthesis may be more forgiving than a posteriorly or laterally positioned prosthesis. The outcome of this study may provide a better insight into the possible consequences of meniscus prosthesis positioning errors for the patient and the prosthesis functionality.

In the Absence of Running: From Injury and Medical Intervention to Art

In recent years, I have developed an endurance running art-practice as part of a larger inquiry into the performative nature of human physical activity. In the Absence of Running is series of artworks made using images from medical arthroscopic interventions following the diagnosis of medial meniscus tears to the cartilage and osteoarthritis in both my knees. Faced with not being able to run or to make artworks using running in the long-term, I turned to the tools of medical intervention. If a camera was going inside my knee for the purpose of surgery, I would use it for the purpose of art. The resulting videos and photographs led to a contemplation on the image and viewing practices not previously anticipated, not least on the now endemic uses of advanced imaging technologies as integral parts of surgical operations. Their reassembly as a stop-frame animation and artist's book in physical and electronic form enabled a process of slowing down and re-engagement with the image and physicality of the book itself and processes and with practices of viewing. This was important in reasserting the sense of human agency in our relationship to images in a world where this appears to be increasingly absent.

[Preventive laser treatment of tractional symptomatic retinal flap tears: long-term outcomes]

Tractional flap tears are the main cause of the development of regmatogenic retinal detachment (RRD). The main immediate treatment method for it is laser retinal coagulation.

PURPOSE

Case monitoring of tractional symptomatic flap tears after laser treatment.

MATERIAL AND METHODS

From 2014 to 2019 we observed 119 patients (130 eyes) with peripheral flap (horseshoe) retinal tears in acute posterior vitreous detachment. Laser coagulation of the retina was performed using Navilas 577s (577 nm), OcuLight GL (532 nm). Laser retinotomy of horseshoe tear flap and dissection of overhanging vessels were performed using Nd:YAG-ultra Q Reflex laser (1064 nm) and controlled with RTVue XR Avanti.

RESULTS

At the initial examination before the preventive laser coagulation, the following conditions were found: regmatogenous retinal detachment (RRD) - 8 eyes (6.2%), partial hemophthalmus - 29 (22.3%), preretinal hemorrhage - 15 (11.5%), epiretinal membrane - 9 (6.9%), non-full-thickness macular retinal breaks - 6 (4.6%), peripheral changes: retinal holes - 16 (12.3%), tears with operculum - 5 (3.8%), retinal degenerations - 40 eyes (30.8%). Observation for 5 years after laser retinopexy revealed new pathological changes: flap tears - 13 (10.6%); holes - 9 (7.4%); tears with operculum - 5 (4.1%); vitreoretinal tuft - 6 (4.9%); RRD - 3 cases (2.5%). In 16 patients (16 eyes) with horseshoe tear and pronounced vitreoretinal traction, the flap retinotomy was performed, which eliminated the traction component and prevented the development of RRD.

CONCLUSION

Follow-up of tractional symptomatic flap tears for 5 years after preventive laser retinopexy revealed the appearance of retinal detachment in 2.5% of cases. Laser retinotomy of horseshoe tear after barrier retinopexy eliminated the traction component and helped prevent the development of RRD.

Ramp lesions are frequently missed in ACL-deficient knees and should be repaired in case of instability

PURPOSE

The aim of the current study was (1) to provide an overview of common definitions and classification systems of ramp lesions (RL) and (2) to systematically review the available literature with regard to the diagnosis and treatment of RLs in anterior cruciate ligament (ACL)-deficient knees.

METHODS

Following the PRISMA guidelines, MEDLINE and Scopus were searched for articles (1) reporting on acute or chronic ACL injuries, (2) with concomitant medial meniscus injury, (3) located at the posterior meniscocapsular attachment site (and red-red zone). Ex vivo studies, reviews and technical notes were excluded.

RESULTS

Twenty-seven studies were included based on the criteria mentioned above. RLs are common in ACL-deficient knees with a prevalence ranging from 9 to 24%. RLs should especially be suspected in younger patients, patients with an increased meniscal slope and in patients with prolonged time from injury to surgery. The sensitivity of MRI for the detection of RLs ranges from 48 to 86% at a specificity of 79-99%. For arthroscopy, RLs are easily missed through standard anterior portals (sensitivity 0-38%). RL repair leads to a significant improvement of subjective knee scores, regardless of the specific fixation technique. For stable RLs, the literature suggests equivalent postoperative stability for trephination and abrasion compared to surgical RL repair.

CONCLUSION

Ramp lesions are frequently missed in ACL-deficient knees on standard arthroscopy with anterior portals only. If a RL is suspected, exploration via an additional posteromedial portal is indicated. In case of instability, RL repair should be performed.

LEVEL OF EVIDENCE

IV.

Liver-derived IGF-I is not required for protection against osteoarthritis in male mice

Insulin-like growth factor-I (IGF-I) is anabolic for cartilage and important for cartilage integrity, which might suggest a connection between IGF-I and osteoarthritis (OA) development. However, the results of studies performed so far are conflicting, and we aimed to clarify the role of endocrine IGF-I in rodent OA. Male mice with inducible inactivation of circulating, liver-derived IGF-I (LI-IGF-I^-/- mice, serum IGF-I reduced by ~80%) were used. Experimental OA was induced in young adult LI-IGF-I^-/- and control mice by destabilization of the medial meniscus (DMM); age-related OA was also evaluated in 1-yr-old mice. DMM-operated LI-IGF-I^-/- mice had thinner lateral subchondral bone plate in tibia compared with control mice, whereas osteophyte volume and articular cartilage damage were unaffected at the medial side of the DMM knee. However, the control mice but not the LI-IGF-I^-/- mice also developed mild OA on the lateral side of the DMM knee compared with the unoperated knee. One-year-old LI-IGF-I^-/- mice had lower mid-diaphyseal cortical bone area than the 1-yr-old control mice, whereas analyses of joint tissues displayed smaller osteophyte volume and thicker calcified cartilage than the control mice. There was no difference in OA severity in the articular cartilage between old LI-IGF-I^-/- and control mice. Our study is the first to investigate whether there is an association between circulating IGF-I and OA in mice. We conclude that, although there is an ~80% reduction of circulating IGF-I and a decrease in cortical bone in male LI-IGF-I^-/- mice, cartilage damage is clearly not intensified and may instead be slightly reduced.

Editorial Commentary: Failure With Continuity: Redefining Healing With Meniscal Root Repair

The importance of the medial meniscus posterior root for preserving knee joint kinematics, joint contact pressures, and articular cartilage integrity is well recognized. Medial meniscus root repair generally is associated with favorable clinical outcomes and radiographic changes compared with conservative treatment or subtotal meniscectomy; however, second-look arthroscopy often reveals some laxity at the repair site. Even in this latter situation of "failure with continuity" of the meniscus root repair, there may be benefit in delaying progression of radiographic degeneration changes. Given that the displacement of the repair often occurs with premature rehabilitative loading, it is important to delay the progression of weight-bearing until adequate healing has occurred.

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.

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.

Baseline radiographic osteoarthritis and semi-quantitatively assessed meniscal damage and extrusion and cartilage damage on MRI is related to quantitatively defined cartilage thickness loss in knee osteoarthritis: the Multicenter Osteoarthritis Study

OBJECTIVES

To provide a comprehensive simultaneous relation of various semiquantitative knee OA MRI features as well as the presence of baseline radiographic osteoarthritis (OA) to quantitative longitudinal cartilage loss.

METHODS

We studied Multicenter OA Study (MOST) participants from a longitudinal observational study that included quantitative MRI measurement of cartilage thickness. These subjects also had Whole Organ MRI Score (WORMS) scoring of cartilage damage, bone marrow lesions (BMLs), meniscal pathology, and synovitis, as well as baseline radiographic evaluation for Kellgren and Lawrence (KL) grading. Knee compartments were classified as progressors when exceeding thresholds of measurement variability in normal knees. All potential risk factors of cartilage loss were dichotomized into "present" (score ≥2 for cartilage, ≥1 for others) or "absent". Differences in baseline scores of ipsi-compartmental risk factors were compared between progressor and non-progressor knees by multivariable logistic regression, adjusting for age, sex, body mass index, alignment axis (degrees) and baseline KL grade. Odds ratios (OR) and 95% CIs were calculated for medial femorotibial compartment (MFTC) and lateral femorotibial compartment (LFTC) cartilage loss. Cartilage loss across both compartments was studied using Generalized Estimating Equations.

RESULTS

196 knees of 196 participants were included (age 59.8 ± 6.3 years [mean ± SD], BMI 29.5 ± 4.6, 62% women). For combined analyses of MFTC and LFTC, baseline factors related to cartilage loss were radiographic OA (KL grade ≥2: aOR 4.8 [2.4-9.5], cartilage damage (aOR 2.3 [1.2-4.4])), meniscal damage (aOR 3.9 [2.1-7.4]) and extrusion (aOR 2.9 [1.6-5.3]), all in the ipsilateral compartment, but not BMLs or synovitis.

CONCLUSION

Baseline radiographic OA and semiquantitatively (SQ) assessed MRI-detected cartilage damage, meniscal damage and extrusion, but not BMLs or synovitis is related to quantitatively measured ipsi-compartmental cartilage thinning over 30 months.

Gender differences in the accuracy of joint line tenderness for arthroscopically confirmed meniscal tears

INTRODUCTION

The reliability of joint line tenderness was previously investigated among other clinical tests for the diagnosis of meniscal pathology with variable results. The aim of this study was to evaluate and compare the accuracy of joint line tenderness as a clinical diagnosing test for arthroscopically confirmed meniscal tears between males and females.

MATERIALS AND METHODS

For the purpose of preoperative joint line tenderness accuracy calculations, this study included male and female groups of patients who have had knee arthroscopy following preoperative diagnosis of meniscal tear. Overall, 195 patients were included in the study, 134 males and 61 females. The mean age was 43.4 (13-76) years.

RESULTS

In the male group, the diagnosis of meniscal tear by joint line tenderness was correct in 84 (62.7%) of 134 knees for the medial side and in 115 (85.8%) for the lateral side. In the female group, the diagnosis was correct in 35 (57.4%) of 61 knees for the medial side and in 57 (93.4%) for the lateral side. In order to refine the accuracy of medial joint line tenderness, the data were recalculated for patients with medial meniscal tears and no chondral lesion or cruciate ligament tears; however, the accuracy remained low.

CONCLUSIONS

The physical finding of joint line tenderness of the knee as a test for lateral meniscal tear was found reliable in both males and females. For medial meniscal tears, the test had low reliability and thus less useful if used alone, in both genders.