Southern California Institute for Research and Education

Plastic pollution is ubiquitous throughout the marine environment, yet estimates of the global abundance and weight of floating plastics have lacked data, particularly from the Southern Hemisphere and remote regions. Here we report an estimate of the total number of plastic particles and their weight floating in the world's oceans from 24 expeditions (2007-2013) across all five sub-tropical gyres, costal Australia, Bay of Bengal and the Mediterranean Sea conducting surface net tows (N = 680) and visual survey transects of large plastic debris (N = 891). Using an oceanographic model of floating debris dispersal calibrated by our data, and correcting for wind-driven vertical mixing, we estimate a minimum of 5.25 trillion particles weighing 268,940 tons. When comparing between four size classes, two microplastic <4.75 mm and meso- and macroplastic >4.75 mm, a tremendous loss of microplastics is observed from the sea surface compared to expected rates of fragmentation, suggesting there are mechanisms at play that remove <4.75 mm plastic particles from the ocean surface.

The Mediterranean Sea has been recently proposed as one of the most impacted regions of the world with regards to microplastics, however the polymeric composition of these floating particles is still largely unknown. Here we present the results of a large-scale survey of neustonic micro- and meso-plastics floating in Mediterranean waters, providing the first extensive characterization of their chemical identity as well as detailed information on their abundance and geographical distribution. All particles >700 μm collected in our samples were identified through FT-IR analysis (n = 4050 particles), shedding for the first time light on the polymeric diversity of this emerging pollutant. Sixteen different classes of synthetic materials were identified. Low-density polymers such as polyethylene and polypropylene were the most abundant compounds, followed by polyamides, plastic-based paints, polyvinyl chloride, polystyrene and polyvinyl alcohol. Less frequent polymers included polyethylene terephthalate, polyisoprene, poly(vinyl stearate), ethylene-vinyl acetate, polyepoxide, paraffin wax and polycaprolactone, a biodegradable polyester reported for the first time floating in off-shore waters. Geographical differences in sample composition were also observed, demonstrating sub-basin scale heterogeneity in plastics distribution and likely reflecting a complex interplay between pollution sources, sinks and residence times of different polymers at sea.

As global awareness, science, and policy interventions for plastic escalate, institutions around the world are seeking preventative strategies. Central to this is the need for precise global time series of plastic pollution with which we can assess whether implemented policies are effective, but at present we lack these data. To address this need, we used previously published and new data on floating ocean plastics (n = 11,777 stations) to create a global time-series that estimates the average counts and mass of small plastics in the ocean surface layer from 1979 to 2019. Today's global abundance is estimated at approximately 82-358 trillion plastic particles weighing 1.1-4.9 million tonnes. We observed no clear detectable trend until 1990, a fluctuating but stagnant trend from then until 2005, and a rapid increase until the present. This observed acceleration of plastic densities in the world's oceans, also reported for beaches around the globe, demands urgent international policy interventions.

BACKGROUND: Full-thickness defects measuring 3 mm in diameter have been commonly used in studies of rabbits to evaluate new procedures designed to improve the quality of articular cartilage repair. These defects initially heal spontaneously. However, little information is available on the characteristics of repair of larger defects. The objective of the present study was to define the characteristics of repair of 6-mm full-thickness osteochondral defects in the adult Spanish goat. METHODS: Full-thickness osteochondral defects measuring 6 x 6 mm were created in the medial femoral condyle of the knee joint of adult female Spanish goats. The untreated defects were allowed to heal spontaneously. The knee joints were removed, and the defects were examined at ten time-intervals, ranging from time zero (immediately after creation of the defect) to one year postoperatively. The defects were examined grossly, microradiographically, histologically, and with magnetic resonance imaging and computed tomography. RESULTS: The 6-mm osteochondral defects did not heal. Moreover, heretofore undescribed progressive, deleterious changes occurred in the osseous walls of the defect and the articular cartilage surrounding the defect. These changes resulted in a progressive increase in the size of the defect, the formation of a large cavitary lesion, and the collapse of both the surrounding subchondral bone and the articular cartilage into the periphery of the defect. Resorption of the osseous walls of the defect was first noted by one week, and it was associated with extensive osteoclastic activity in the trabecular bone of the walls of the defect. Flattening and deformation of the articular cartilage at the edges of the defect was also observed at this time. By twelve weeks, bone resorption had transformed the surgically created defect into a larger cavitary lesion, and the articular cartilage and subchondral bone surrounding the defect had collapsed into the periphery of the defect. By twenty-six weeks, bone resorption had ceased and the osseous walls of the lesion had become sclerotic. The cavitary lesion did not become filled in with fibrocartilage. Instead, a cystic lesion was found in the center of most of the cavitary lesions. Only a thin layer of fibrocartilage was present on the sclerotic osseous walls of the defect. Specimens examined at one year postoperatively showed similar characteristics. CONCLUSIONS: Full-thickness osteochondral defects, measuring 6 mm in both diameter and depth, that are created in the medial femoral condyle of the knee joint of adult Spanish goats do not heal spontaneously. Instead, they undergo progressive changes resulting in resorption of the osseous walls of the defect, the formation of a large cavitary lesion, and the collapse of the surrounding articular cartilage and subchondral bone. CLINICAL RELEVANCE: As surgeons apply new reparative procedures to larger areas of full-thickness articular cartilage loss, we believe that it is important to consider the potential deleterious effects of a "zone of influence" secondary to the creation of a large defect in the subchondral bone. When biologic and synthetic matrices with or without cells or bioactive factors are placed into surgically created osseous defects, the osseous walls serve as shoulders to protect and stabilize the preliminary repair process. It is important to protect the repair process until biologic incorporation occurs and the chondrogenic switch turns the cells on to synthesize an articular-cartilage-like matrix. It takes a varying period of time to fill a large, surgically created bone defect underlying a chondral surface. The repair of such a defect requires bone synthesis and the reestablishment of a subchondral plate with a tidemark transition to the new overlying articular surface. The prevention of secondary changes in the surrounding bone and articular cartilage and the durability of the new reparative tissue making up the articulating surface are issues that must be addressed in future studies.

Arthrofibrosis is one of the recognized complications following traditional anterior cruciate ligament (ACL) reconstruction. With the advent of arthroscopic assisted ACL reconstructions, the extent of potential arthrofibrosis appeared to be less. However, 13 patients after intra-articular ACL reconstruction using a patella tendon autograft developed a similar symptom complex. In addition to postoperative loss of full extension, there was an audible and palpable clunk with terminal extension. These patients had similar arthroscopic findings of a nodule that formed anterolateral to the tibial tunnel placement of the graft. The arthroscopic appearance of the soft tissue mass with its surface vessels was reminiscent of a "cyclops." After arthroscopy with debridement and manipulation of the knee, extension was improved in all cases. The average range of motion immediately after the procedure was 6.0-130 degrees, compared with 16-103 degrees preoperatively. The range of motion at last follow-up averaged 3.8 degrees of extension and 138 degrees of flexion. All patients had greater than 130 degrees of flexion. There were no complications attributed to the manipulation and arthroscopic lysis of adhesions, and no patient experienced loss of graft integrity or knee stability. The "cyclops" nodule was examined grossly and microscopically and demonstrated peripheral fibrous tissue with a central region of granulation tissue in all specimens. In addition, two specimens were noted to include bony fragments and three specimens contained cartilaginous tissue.

The primary goal of the present article is to compare expectancy models with competing attitude models of alcohol use. First, several methodological issues in expectancy research were addressed, to more adequately compare the theoretical models. Study 1 examined the effect of possible self-report biases on associations among expectancy constructs and alcohol use. In Studies 2 and 3, the basic distinction between general factors of positive and negative alcohol expectancies was investigated in both cross-sectional and prospective models. Alternative predictions that were based on competing expectancy and attitude theories were evaluated primarily in Study 3. Results from these studies supported the validity of the expectancy constructs and the proposed distinctions among expectancy and attitude constructs-in terms of strong discriminant validity, absence of self-report bias, and differential prediction of alcohol use. Furthermore, the findings favored certain expectancy models over alternative attitude models of alcohol use, reaffirming the usefulness of the expectancy framework.

Plastics and other artificial materials pose new risks to the health of the ocean. Anthropogenic debris travels across large distances and is ubiquitous in the water and on shorelines, yet, observations of its sources, composition, pathways, and distributions in the ocean are very sparse and inaccurate. Total amounts of plastics and other man-made debris in the ocean and on the shore, temporal trends in these amounts under exponentially increasing production, as well as degradation processes, vertical fluxes, and time scales are largely unknown. Present ocean circulation models are not able to accurately simulate drift of debris because of its complex hydrodynamics. In this paper we discuss the structure of the future integrated marine debris observing system (IMDOS) that is required to provide long-term monitoring of the state of this anthropogenic pollution and support operational activities to mitigate impacts on the ecosystem and on the safety of maritime activity. The proposed observing system integrates remote sensing and in situ observations. Also, models are used to optimize the design of the system and, in turn, they will be gradually improved using the products of the system. Remote sensing technologies will provide spatially coherent coverage and consistent surveying time series at local to global scale. Optical sensors, including high-resolution imaging, multi-and hyperspectral, fluorescence, and Raman technologies, as well as SAR will be used to measure different types of debris. They will be implemented in a variety of platforms, from hand-held tools to ship-, buoy-, aircraft-, and satellite-based sensors. A network of in situ observations, including reports from volunteers, citizen scientists and ships of opportunity, will be developed to provide data for calibration/validation of remote sensors and to monitor the spread of plastic pollution and other marine debris. IMDOS will interact with other observing systems monitoring physical, chemical, and biological processes in the ocean and on shorelines as well as the state of the ecosystem, maritime activities and safety, drift of sea ice, etc. The synthesized data will support innovative multi-disciplinary research and serve a diverse community of users.

BACKGROUND: To achieve their potential therapeutic benefit, hyaluronic acid derivatives should be injected directly into the knee joint space and not into the anterior fat pad or the subsynovial tissues. In the absence of a knee effusion, reproducible needle placement into the intra-articular space presents a challenge to the clinician. METHODS: The accuracy of needle placement was assessed in a prospective series of 240 consecutive injections in patients without clinical knee effusion. The injections were performed by one orthopaedic surgeon using a 2.0-in (5.1-cm) 21-gauge needle through three commonly employed knee joint portals: anteromedial, anterolateral, and lateral midpatellar. Accuracy rates for needle placement were confirmed with fluoroscopic imaging to document the dispersion pattern of injected contrast material. RESULTS: Of eighty injections performed through an anterolateral portal, fifty-seven were confirmed to have been placed in the intra-articular space on the first attempt (an accuracy rate of 71%). Sixty of eighty injections performed through an anteromedial approach were intra-articular on the first attempt (75% accuracy rate), as were seventy-four of eighty injections performed through a lateral midpatellar portal (93% accuracy rate). CONCLUSIONS: Using real-time fluoroscopic imaging with contrast material, we demonstrated the difficulty of accurately placing a needle into the intra-articular space of the knee when an effusion is not present. This study revealed that a lateral midpatellar injection (an injection into the patellofemoral joint) was intra-articular 93% of the time and was more accurate than injections performed by the same orthopaedic surgeon using either of the other two portals. This study highlights the need for clinicians to refine injection techniques for delivering intra-articular therapeutic substances that are intended to coat the articular surfaces of the knee joint.

We performed a retrospective study of 616 patients (636 shoulders) who had subacromial impingement syndrome to assess the results of non-operative treatment. The diagnosis was made on the basis of a positive impingement sign and the absence of other abnormalities of the shoulder, such as full-thickness tears of the rotator cuff, osteoarthrosis of the acromioclavicular joint, instability of the glenohumeral joint, or adhesive capsulitis. All patients were managed with anti-inflammatory medication and a specific, supervised physical-therapy regimen consisting of isotonic exercises for strengthening of the rotator cuff. The average duration of follow-up was twenty-seven months (range, six to eighty-one months). Over-all, 413 patients (67 per cent) had a satisfactory result. One hundred and seventy-two patients (28 per cent) had no improvement and went on to have an arthroscopic subacromial decompression. Thirty-one patients (5 per cent) had an unsatisfactory result but declined additional treatment. Seventy-four (18 per cent) of the 413 patients who had a successful result had a recurrence of the symptoms during the follow-up period; the symptoms resolved with rest or after resumption of the exercise program. The patients were stratified according to age, the duration of symptoms, and acromial morphology. Patients who were twenty years old or less and those who were forty-one to sixty years old fared better than those who were twenty-one to forty years old. Patients who were more than sixty years old had the poorest results. Sixty-seven (78 per cent) of the eighty-six patients in whom the symptoms had been present for less than four weeks had a satisfactory result, compared with 144 (63 per cent) of the 228 who had had the symptoms for one to six months and with 202 (67 per cent) of the 302 who had had the symptoms for more than six months. Thirty-two (91 per cent) of the thirty-five patients who had a type-I acromion had a successful result, compared with 173 (68 per cent) of the 256 who had a type-II acromion and with 208 (64 per cent) of the 325 who had a type-III acromion. Shoulder dominance, gender, and concomitant tenderness of the acromioclavicular joint did not affect the result significantly (p = 0.084, 0.555, and 0.365, respectively).

Articular cartilage injury and degeneration is a frequent occurrence in synovial joints. Treatment of these articular cartilage lesions are a challenge because this tissue is incapable of quality repair and/or regeneration to its native state. Nonoperative treatments endeavor to control symptoms, and include anti-inflammatory medication, viscosupplementation, bracing, orthotics, and activity modification. Techniques to stimulate the intrinsic repair (fibrocartilage) process include drilling, abrasion, and microfracture of the subchondral bone. Currently, the clinical biologic approaches to treat cartilage defects include autologous chondrocyte implantation, periosteal transfer, and osteochondral autograft or allograft transplantation. Newer strategies employing tissue engineering being studied involve the use of combinations of progenitor cells, bioactive factors, and matrices, and the use of focal synthetic devices. Many new and innovative treatments are being explored in this exciting field. However, there is a paucity of prospective, randomized controlled clinical trials that have compared the various techniques, treatment options, indications and efficacy.

The current study sought to identify classes of growth trajectories of adolescent alcohol use and to examine the predictors and outcomes associated with the classes. Alcohol use was assessed from Grades 7 to 12 in a school-based sample. Latent growth mixture modeling was used, and results indicated 5 discrete longitudinal drinking patterns. The 2 most common drinking patterns included occasional very light drinking from Grades 7 to 12 and moderate escalation in both quantity and frequency of alcohol use. One group drank infrequently but at high levels throughout the study period. Another group exhibited rapid escalation in both quantity and frequency. The final group started at high levels of frequency and quantity in Grade 7 and showed rapid de-escalation in frequency. Emotional distress and risk taking distinguished the classes, and all classes, particularly rapid escalators, showed elevated levels of alcohol-related problems relative to occasional very light drinkers.

Three groups of top level female gymnasts of preelite, elite, national and Olympic caliber were studied without regard to back pain or injury. These athletes were compared to a similar group of national caliber female swimmers. Magnetic resonance imaging scans of each participant were used to document disk or bony abnormalities. The relationship between magnetic resonance imaging findings and age, height, weight, previous injuries, back symptoms, and hours of training per week each year was examined. Nine percent of preelite (1/11), 43% of elite (6/14), and 63% of Olympic level (5/8) gymnasts had spine abnormalities; 15.8% of all swimmers had spine abnormalities. Average hours of training per week and age were found to be associated with abnormalities seen on magnetic resonance imaging. Increased intensity and length of training correlated with previous data that suggests the female gymnast is prone to spine injuries.

Magnetic resonance images (MRI) were performed within three weeks of anterior cruciate ligament (ACL) rupture on 75 skeletally mature patients. Occult bony lesions were documented in 64 (85%) of the patients. Of the 64 patients with bone injuries, 83% had lesions of the lateral compartment. The lateral femoral condyle was involved in 50%, and the lateral tibial plateau was injured in 50% of the patients with changes. Nineteen of the 64 patients had more than one area of bony injury. Although the majority of bony lesions resolve, permanent alterations remained in some cases. This study has implications that may affect rehabilitation and the long-term prognosis in those patients with extensive bony and associated articular cartilage injuries.

Background: The objective of this study is to determine whether there is a relationship between the duration of sustained spinal cord compression and the extent of spinal cord injury and the capacity for functional recovery after decompression. Methods: Sixteen dogs underwent sustained spinal cord compression for thirty or 180 minutes. The cords were compressed with use of a loading device with a hydraulic piston. A pressure transducer was attached to the surface of the piston, which transmitted real-time spinal cord interface pressures to a data-acquisition system. Somatosensory evoked potentials were monitored during a sixty-minute recovery period as well as at twenty-eight days after the injury. Functional motor recovery was judged throughout a twenty-six-day period after the injury with use of a battery of motor tasks. The volume of the lesion and damage to the tissue were assessed with both magnetic resonance imaging and histological analysis. Results: Sustained spinal cord compression was associated with a gradual decline in interface pressure. Despite this, there was continuous decline in the amplitude of the somatosensory evoked potentials, which did not return until the cord was decompressed. Within one hour after the decompression, the dogs in the thirty-minute-compression group had recovery of somatosensory evoked potentials, but no animal had such recovery in the 180-minute group. Recovery of the somatosensory evoked potentials in the thirty-minute group was sustained over the twenty-eight days after the injury. Motor tests demonstrated rapid recovery of hindlimb motor function in the thirty-minute group, but there was considerable impairment in the 180-minute group. Within two weeks after the injury, balance, cadence, stair-climbing, and the ability to walk up an inclined plane were significantly better in the thirty-minute group than in the 180-minute group. The longer duration of compression produced lesions of significantly greater volume, which corresponded to the long-term functional outcome. Conclusions: The relatively rapid viscoelastic relaxation of the spinal cord during the early phase of sustained cord compression suggests that there are mechanisms of secondary injury that are linked to tissue displacement. Longer periods of displacement allow propagation of the secondary injury process, resulting in a lack of recovery of somatosensory evoked potentials, limited functional recovery, and more extensive tissue damage. Clinical Relevance: The findings underscore the importance of timely decompression to improve long-term functional recovery after spinal cord injury.

Shoes have been implicated as being responsible for the majority of foot deformities and problems that physicians encounter in women. A total of 356 women were studied in this investigation to evaluate trends in women's shoe wear and their effect on the development of foot deformities and pain. The majority of women in this study wore shoes that were too small for their feet, had foot pain and deformity, and had increased shoe size since the age of 20. Few women had their feet measured in over 5 years. The women without foot pain or deformities also wore shoes that were smaller than their feet but to a lesser degree.

Ten cases of osteochondritis dissecans of the humeral capitellum are reviewed in seven high-performance female gymnasts, ranging in age from 10 to 17 years old. All but one were evaluated and treated with arthroscopy and/or arthrotomy, with curettage of loose articular margins, drilling of the lesion, and removal of loose bodies. The average length of follow-up is 2.9 years, and includes interview, physical examination, and roentgenographic evaluation. This injury has been previously described in relation to compressive forces across the radiocapitellar joint from repetitive valgus loading in a developing epiphysis. Only one of the athletes, at the time of follow-up, was still in competitive gymnastics. Each has a minimal limitation in range of motion, with crepitus and often catching noted by history and on examination. These cases double the limited literature on this injury in young, female gymnasts. They stimulate concern for the proper and early evaluation and treatment of elbow injuries in this at risk group. Once the bony changes in the capitellum are detected, and pain remains despite conservative management, we have found that symptoms can be improved with surgery, but persist in female gymnasts. Our experience in this more-advanced group is that the return to high-level competitive gymnastics is unlikely.

This prospective study assessed 54 consecutive arthroscopically assisted ACL reconstructions for the amount of postoperative pain relief provided by cold therapy, using the Hot/Ice Thermal Blanket. Twenty-six randomly selected patients undergoing this procedure were compared to a control group consisting of 28 patients having the identical procedure in which the Hot/Ice unit was not used postoperatively. The initial ACL injury in both groups was sports related with the exception of three patients whose injury occurred while on the job. The Hot/Ice Thermal Blanket consists of two rubber pads (blankets) connected by a hose to the main cooling unit. The pads were applied to either side of the operated knee in the operative suite. The pads received fluid which was circulated from the main unit. The temperature of the fluid was set at 50 degrees in the recovery room and the unit was run continuously until the time of discharge, which was approximately 4 days. Hot/Ice patients required 53% less injectable Demerol and 67% less oral Vistaril than patients in the control group. Hot/Ice patients had made the conversion from injectable to oral pain medication an average of 1.2 days sooner than did their non-Hot/Ice counterparts. There was no appreciable difference in length of hospital stay. Physical therapy and nursing records documented a greater percentage of compliant patients in the Hot/Ice group. According to these records the Hot/Ice patients were more helpful in self-assistance, were out of bed and ambulating in the halls more quickly, and did their range of motion exercises with greater ease.(ABSTRACT TRUNCATED AT 250 WORDS)

We developed an in situ freeze-thaw model designed to simulate an ideally placed and oriented autogenous graft of the anterior cruciate ligament. In this model, the anterior cruciate ligament was exposed, and the femoral insertion, tibial insertion, and body of the anterior cruciate ligament were frozen in situ with specially designed freezing probes. Freeze-thaw cycles were repeated five times. We used the technique in thirty-three mature goats to study the biological and biomechanical outcomes of the devitalized and devascularized anterior cruciate ligament at zero, six, and twenty-six weeks after treatment. Thus, the collagen fibers of the simulated autogenous graft remain in normal anatomical position and the simulated graft is fixed under physiological tension. At twenty-six weeks, no statistically significant differences were noted between treated and contralateral control (untreated) ligaments relative to anterior-posterior translation, maximum force to rupture, stiffness in the linear region of the force-length curve, modulus of elasticity in the linear region, strain to maximum stress, or maximum stress. The only statistically significant difference was an increase in cross-sectional area of the ligament. This increase was 22 and 42 per cent greater than that in the control ligaments at six weeks and six months. At six months, the ligaments in the control group had an average mid-cross-sectional area of 17.7 +/- 1.2 square millimeters and the ligaments in the experimental group, 25.2 +/- 3.1 square millimeters. Changes in the size and density of the collagen fibrils also were demonstrated at six months. These observations are in sharp contrast to our previous studies of replacement of the anterior cruciate ligament, in which an allograft of the ligament or an allograft supplemented with a 3M ligament augmentation device (LAD; 3M, St. Paul, Minnesota) was used. In those studies, an average reduction in maximum strength of 75 per cent for the allografts and 50 per cent for the allografts that had a ligament-augmentation device was found at one year. We concluded that devitalized, devascularized anterior cruciate ligaments do not lose strength if the anatomical position and the orientation of the collagen fibers are not altered.

Articular cartilage injury and degeneration is a frequent occurrence in synovial joints. Treatment of these articular cartilage lesions are a challenge because this tissue is incapable of quality repair and/or regeneration to its native state. Nonoperative treatments endeavor to control symptoms, and include anti-inflammatory medication, viscosupplementation, bracing, orthotics, and activity modification. Techniques to stimulate the intrinsic repair (fibrocartilage) process include drilling, abrasion, and microfracture of the subchondral bone. Currently, the clinical biologic approaches to treat cartilage defects include autologous chondrocyte implantation, periosteal transfer, and osteochondral autograft or allograft transplantation. Newer strategies employing tissue engineering being studied involve the use of combinations of progenitor cells, bioactive factors, and matrices, and the use of focal synthetic devices. Many new and innovative treatments are being explored in this exciting field. However, there is a paucity of prospective, randomized controlled clinical trials that have compared the various techniques, treatment options, indications and efficacy.

PURPOSE: Despite the well-documented advantages of meniscal repair over meniscectomy, horizontal cleavage tears (HCTs) are often not repaired. Reported reasons include difficulty performing the repair, potential suture failure due to mechanical stresses, and poor healing rates. In addition, many surgeons have the perception that debriding the tear until the superior and inferior laminae are stable results in a good clinical outcome. Furthermore, many of the tears occur in patients who are older than the generally accepted indicated age for repair and may also have a degenerative component, making them potentially less likely to benefit from repair. This review was performed to evaluate the published outcomes of HCT repairs and test the hypothesis that surgically repaired HCTs have an unacceptably low rate of success. METHODS: A systematic search of the PubMed and Embase databases was performed in December 2013 to identify studies in which meniscal HCTs were repaired. Inclusion criteria for the analysis were English language, reference to a patient with an HCT repaired by any method, and a report of at least 1 postoperative outcome. For the purposes of this review, a failed outcome was defined as the need for reoperation. RESULTS: More than 16,000 abstracts were returned in the search. From these abstracts, we identified 210 articles for further review, of which 9 met the inclusion criteria. A total of 98 repairs of horizontal tears were evaluated in these studies. By use of reoperation as the criterion for treatment failure, 77 of the repairs were successful, for an overall success rate of 77.8%. CONCLUSIONS: The literature does not support the hypothesis that surgically repaired HCTs have an unacceptably low rate of success. Rather, our results show that existing studies of repaired HCTs show a comparable success rate to repairs of other types of meniscal tears. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.