ABSTRACT
PURPOSE: To report midterm outcomes after primary medial and lateral meniscal allograft transplantation (MAT) with fresh-frozen allografts implanted with the bridge-in-slot technique in the adolescent patient population. METHODS: Adolescent patients less than 18 years old at the time of primary MAT from 1999 to 2016 were retrospectively identified. International Knee Documentation Committee (IKDC) subjective form, Lysholm, and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales scores were collected before surgery and at 1-year, 2-year, and a minimum 5-year follow-up. Thresholds for achieving clinically significant outcomes were calculated, and the proportion of patients achieving minimal clinically important difference (MCID), patient-acceptable symptomatic state (PASS), and substantial clinical benefit (SCB) was determined. Meniscus reoperation (partial, subtotal, or total meniscectomy, repair, or failure) and failure (revision MAT or conversion to arthroplasty) rates were determined. RESULTS: Forty-four (female n = 33; male n = 11) of 62 identified patients met inclusion criteria and were followed for a mean of 9.5 ± 3.8 years (range, 5.0-17.7). Lateral MAT was performed in most patients (n = 35/44 [80%]). Isolated MAT was performed in 27 (61%) patients. Common concomitant procedures included osteochondral allograft transplantation (32%), autologous chondrocyte implantation (18%), and anterior cruciate ligament reconstruction (14%). MCID, PASS, and SCB were achieved by patients at a minimum 5-year follow-up for IKDC (62%; 76%; 31%), Lysholm (62%; 79%; 23%), and KOOS questionnaires (Pain [65%; 81%; 41%], Symptoms [58%; 81%; 47%], Activities of Daily Living [53%; 77%; 35%], Sport [86%; 75%; 50%], and Quality of Life [59%; 81%; 59%]), respectively. Fourteen patients (32%) underwent reoperation at an average of 5.0 ± 4.3 years (range, 0.8-14.0) after MAT. Three (7%) patients met criteria for failure, requiring revision MAT an average of 3.8 ± 1.1 years (range, 2.8-4.9) after transplantation. No patients underwent arthroplasty. Overall survival free from failure at 1, 2, 5, and 10 years was 100%, 100%, 93%, and 93%, respectively. At the time of final follow-up, 80% of patients reported satisfaction with their current physical status. CONCLUSIONS: Primary MAT in adolescent patients resulted in significant and durable functional improvements at mid- to long-term follow-up. At an average of 9.5 years after surgery, meniscal reoperation rate was 32% whereas graft survival free of revision MAT was 93%. Adolescents undergoing MAT demonstrated similar functional outcomes and graft survivability when compared to available adult MAT literature. LEVEL OF EVIDENCE: Level IV, retrospective case series.
Subject(s)
Anterior Cruciate Ligament Reconstruction , Meniscus , Adult , Humans , Adolescent , Female , Male , Retrospective Studies , Activities of Daily Living , Follow-Up Studies , Quality of Life , Arthroplasty , Menisci, Tibial/surgery , AllograftsABSTRACT
PURPOSE: To report the mid-term outcomes of patients who underwent revision meniscal allograft transplantation (RMAT) and compare survivorship free from reoperation and failure with a matched cohort of patients who underwent primary meniscal allograft transplantation (PMAT). METHODS: A retrospective review of prospectively collected data identified patients who underwent RMAT and PMAT between 1999 and 2017. A cohort of PMAT patients matched at a ratio of 2:1 with respect to age, body mass index, sex, and concomitant procedures served as the control group. Patient-reported outcome measures (PROMs) at baseline and at a minimum of 5 years postoperatively were collected. PROMs and the achievement of clinically significant outcomes were analyzed within groups. Graft survivorship free from meniscal reoperation and failure (arthroplasty or subsequent RMAT) was compared between cohorts using log-rank testing. RESULTS: During the study period, 22 RMATs were performed in 22 patients. Of these RMAT patients, 16 met the inclusion criteria (73% follow-up rate). The mean age of RMAT patients was 29.7 ± 9.3 years, and the mean follow-up period was 9.9 ± 4.2 years (range, 5.4-16.8 years). There were no differences between the RMAT cohort and the 32 matched PMAT patients with respect to age (P = .292), body mass index (P = .623), sex (P = .537), concomitant procedures (P ≥ .286), or baseline PROMs (P ≥ .066). The patient acceptable symptomatic state was achieved by the RMAT cohort for the subjective International Knee Documentation Committee score (70%), Lysholm score (38%), and Knee Injury and Osteoarthritis Outcome Score subscales (Pain [73%], Symptoms [64%], Sport [45%], Activities of Daily Living [55%], and Quality of Life [36%]). In the RMAT cohort, 5 patients (31%) underwent subsequent reoperation at a mean of 4.7 ± 2.1 years (range, 1.7-6.7 years) and 5 patients met the criteria for failure at a mean of 4.9 ± 2.9 years (range, 1.2-8.4 years). There were no significant differences in survivorship free from reoperation (P = .735) or failure (P = .170) between the RMAT and PMAT cohorts. CONCLUSIONS: At mid-term follow-up, most patients who underwent RMAT achieved the patient acceptable symptomatic state for the subjective International Knee Documentation Committee score and the Knee Injury and Osteoarthritis Outcome Score subscales of Pain, Symptoms, and Activities of Daily Living. Additionally, there were no differences in survival free from meniscal reoperation or failure between the PMAT and RMAT cohorts. LEVEL OF EVIDENCE: Level III, retrospective comparative cohort.
Subject(s)
Knee Injuries , Osteoarthritis , Humans , Child, Preschool , Child , Adolescent , Reoperation , Menisci, Tibial/transplantation , Retrospective Studies , Follow-Up Studies , Activities of Daily Living , Quality of Life , Knee Joint/surgery , Osteoarthritis/surgery , Allografts , Pain/surgery , Knee Injuries/surgery , Patient Reported Outcome MeasuresABSTRACT
BACKGROUND: Meniscal allograft transplantation (MAT) has been shown to provide clinical benefits in patients with symptomatic meniscal deficiency in the short term and midterm. There is, however, a paucity of data regarding long-term outcomes after MAT using fresh-frozen allografts and the bridge-in-slot technique. PURPOSE: To report clinical outcomes and revision rates after primary MAT with fresh-frozen allografts and the bridge-in-slot technique in a large case series of patients at a 10-year minimum follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective review of prospectively collected data was performed on patients undergoing primary MAT between 2001 and 2012. Lysholm, International Knee Documentation Committee subjective form, and Knee injury and Osteoarthritis Outcome Score subscales were collected preoperatively and at 1-, 2-, 5-, and minimum 10-year follow-ups. Cox proportional hazards modeling was used to identify variables associated with reoperation and failure, defined as revision MAT or conversion to arthroplasty. Reoperation was defined as a subsequent surgical intervention on the transplanted meniscus, including partial or total meniscectomy, meniscal repair, or failure as defined in the previous sentence. RESULTS: A total of 174 patients undergoing MAT met the inclusion criteria and were followed for a mean of 12.7 ± 2.7 years (range, 10.0-21.0 years). The mean age at surgery was 28.3 ± 10.1 years. The patients were predominantly female (n = 92; 53%), and medial MAT was the most commonly performed procedure (n = 91; 52%). Concomitant procedures were performed in 115 patients (66%), with the most common procedure being osteochondral allograft transplantation (n = 59; 34%). Patients demonstrated statistically significant postoperative improvements at all time points for all patient-reported outcome measures (P≤ .0001). A total of 65 patients (37%) underwent a meniscal reoperation at a mean time of 6.6 ± 5.5 years (range, 0.3-16.7 years) postoperatively. A total of 40 patients (23%) met the criteria for failure at a mean time of 7.3 ± 5.0 years (range, 1.0-17.4 years) after MAT, with 22 of these patients having undergone a previous meniscal reoperation. At the final follow-up, 13 patients (7%) had undergone revision MAT and 27 (15%) had converted to arthroplasty. The MAT survival rates free of meniscal reoperation and failure were 73% and 85% at 10 years and 60% and 72% at 15 years, respectively. At the time of the final follow-up, 86% of patients reported that they were satisfied with their overall postoperative condition. CONCLUSION: Primary MAT demonstrates efficacy and durability with high rates of patient satisfaction at a minimum 10-year follow-up. Patients should be counseled that although reoperation rates may approach 40% at 15 years, rates of overall revision MAT and conversion to arthroplasty remain low at long-term follow-up.
Subject(s)
Arthroplasty, Replacement, Knee , Meniscus , Humans , Female , Adolescent , Young Adult , Adult , Male , Survivorship , Transplantation, Homologous , AllograftsABSTRACT
BACKGROUND: Long-term outcomes of osteochondral allograft (OCA) transplantation to the humeral head have been sparsely reported in the literature. PURPOSE: To evaluate outcomes and survivorship of OCA transplantation to the humeral head in patients with osteochondral defects at a minimum of 10 years of follow-up. METHODS: A registry of patients who underwent humeral head OCA transplantation between 2004 and 2012 was reviewed. Patients completed pre and postoperative surveys including the American Shoulder and Elbow Surgeons score, Simple Shoulder Test, Short Form 12 (SF-12), and the visual analog scale. Failure was defined by conversion to shoulder arthroplasty. RESULTS: Fifteen of 21 (71%) patients with a minimum of ten year of follow-up (mean: 14.2 ± 2.40) were identified. Mean patient age was 26.1 ± 8.8 years at the time of transplantation and eight (53%) patients were male. Surgery was performed on the dominant shoulder in 11 of the 15 (73%) cases. The use of local anesthetic delivered via an intra-articular pain pump was the most often reported underlying etiology of chondral injury (n = 9; 60%). Eight (53%) patients were treated with an allograft plug, while seven (47%) patients were treated with a mushroom cap allograft. At final follow-up, mean American Shoulder and Elbow Surgeons (49.9 to 81.1; P = .048) and Simple Shoulder Test (43.1 to 83.3; P = .010) significantly improved compared to baseline. Changes in mean SF-12 physical (41.4 to 48.1; P = .354), SF-12 mental (57.5 to 51.8; P = .354), and visual analog scale (4.0 to 2.8; P = .618) did not reach statistical significance. Eight (53%) patients required conversion to shoulder arthroplasty at an average of 4.8 ± 4.7 years (range: 0.6-13.2). Kaplan-Meier graft survival probabilities were 60% at 10 years and 41% at 15 years. CONCLUSION: OCA transplantation to the humeral head can result in acceptable long-term function for patients with osteochondral defects. While patient-reported outcomes metrics were generally improved compared to baseline, OCA graft survival probabilities diminished with time. The findings from this study can be used to counsel future patients with significant glenohumeral cartilage injuries and set expectations about the potential for further surgery.
ABSTRACT
PURPOSE: To determine the improvements in patient-reported outcome measures (PROMs) necessary to achieve minimal clinically important difference (MCID), patient-acceptable symptomatic state (PASS), and substantial clinical benefit (SCB) after primary meniscal allograft transplantation (MAT) at a minimum of 5-year follow-up, while identifying variables predictive of achieving clinically significant outcomes (CSOs). METHODS: A retrospective review was performed to identify patients undergoing primary MAT at a single institution from 1999 to 2016. Lysholm, International Knee Documentation Committee (IKDC), and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales were collected before surgery and at a minimum of 5-year follow-up. A distribution-based approach was used to calculate MCID, whereas an anchor-based approach was used to calculate SCB and PASS. Multivariate logistic regression was performed to determine factors associated with CSO achievement. RESULTS: A total of 202 patients undergoing MAT (56% medial, 44% lateral) were included with a mean follow-up of 9.8 ± 4.1 years, age of 29.7 ± 8.5 years, and body mass index (BMI) of 26.5 ± 4.7. Thresholds for achieving MCID, PASS, and SCB, respectively, at a minimum 5-year follow-up for Lysholm (10.3, 74.5, 32.5), IKDC (12.1, 55.6, 29.1), and KOOS subscales questionnaires (Pain [11.0, 70.7, 25.1], Symptoms [11.0, 60.8, 19.6], Activities of Daily Living [10.5, 90.3, 17.9], Sport [16.2, 47.4, 37.5], and Quality of Life [13.6, 40.5, 37.3]) were calculated. Reduced odds of achieving MCID were associated with higher preoperative PROM scores, BMI, patient age, concomitant osteotomy, male sex, and worker's compensation (WC) status. Reduced odds of achieving PASS were associated with lower preoperative PROM scores, higher BMI (particularly ≥30), patient age, and WC status. Reduced odds of achieving SCB were associated with higher preoperative PROM scores and WC status. CONCLUSIONS: This study established the MCID, PASS, and SCB at 5-year minimum follow-up for the Lysholm score, IKDC, and KOOS subscales in patients who underwent MAT. Increased BMI and patient age, male sex, performance of concomitant osteotomy, WC status, and preoperative PROM scores were associated with failure to achieve CSOs after primary MAT at a minimum of 5-year follow-up. LEVEL OF EVIDENCE: Level IV, therapeutic study, retrospective case series.
ABSTRACT
BACKGROUND: Although initial studies have demonstrated that concentrated bone marrow aspirate (cBMA) injections promote rotator cuff repair (RCR) healing, there are no randomized prospective studies investigating clinical efficacy. HYPOTHESIS/PURPOSE: To compare outcomes after arthroscopic RCR (aRCR) with and without cBMA augmentation. It was hypothesized that cBMA augmentation would result in statistically significant improvements in clinical outcomes and rotator cuff structural integrity. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: Patients indicated for aRCR of isolated 1- to 3-cm supraspinatus tendon tears were randomized to receive adjunctive cBMA injection or sham incision. Bone marrow was aspirated from the iliac crest, concentrated using a commercially available system, and injected at the aRCR site after repair. Patients were assessed preoperatively and serially until 2 years postoperatively via the following functional indices: American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), Simple Shoulder Test, 12-Item Short Form Health Survey, and Veterans RAND 12-Item Health Survey. Magnetic resonance imaging (MRI) was performed at 1 year to assess rotator cuff structural integrity according to Sugaya classification. Treatment failure was defined as decreased 1- or 2-year ASES or SANE scores as compared with preoperative baseline, the need for revision RCR, or conversion to total shoulder arthroplasty. RESULTS: An overall 91 patients were enrolled (control, n = 45; cBMA, n = 46): 82 (90%) completed 2-year clinical follow-up and 75 (82%) completed 1-year MRI. Functional indices significantly improved in both groups by 6 months and were sustained at 1 and 2 years (all P < .05). The control group showed significantly greater evidence of rotator cuff retear according to Sugaya classification on 1-year MRI (57% vs 18%; P < .001). Treatment failed for 7 patients in each group (control, 16%; cBMA, 15%). CONCLUSION: cBMA-augmented aRCR of isolated supraspinatus tendon tears may result in a structurally superior repair but largely fails to significantly improve treatment failure rates and patient-reported clinical outcomes when compared with aRCR alone. Additional study is warranted to investigate the long-term benefits of improved repair quality on clinical outcomes and repair failure rates. REGISTRATION: NCT02484950 (ClinicalTrials.gov identifier).
Subject(s)
Biological Products , Rotator Cuff Injuries , Humans , Rotator Cuff/surgery , Prospective Studies , Bone Marrow , Rotator Cuff Injuries/surgery , Treatment Outcome , Magnetic Resonance Imaging , Arthroscopy/methodsABSTRACT
â¢: Pathologic meniscal extrusion can compromise meniscal function, leading to increased contact forces in the tibiofemoral compartment and the acceleration of osteoarthritic changes. â¢: Extrusion is typically defined as radial displacement of ≥3 mm outside the tibial border and is best diagnosed via magnetic resonance imaging, although ultrasonography has also demonstrated encouraging diagnostic utility. â¢: Surgical management of meniscal extrusion is based on the underlying etiology, the patient's symptom profile, the preexisting health of the articular surface, and the risk of future chondral injury and osteoarthritis.
Subject(s)
Osteoarthritis , Tibial Meniscus Injuries , Humans , Magnetic Resonance Imaging/methods , Menisci, Tibial/diagnostic imaging , Menisci, Tibial/surgery , Osteoarthritis/pathology , Tibial Meniscus Injuries/diagnostic imaging , Tibial Meniscus Injuries/surgeryABSTRACT
Rotator cuff repair has benefitted from many technologic advances including the advent of arthroscopy, improved implant materials, and refined repair techniques. Despite our efforts to improve the science of rotator cuff repair, clinical advances have lagged far behind. Graft augmentation of rotator cuff repairs is an emerging and heterogeneous field that has significantly improved both healing rates and patient-reported metrics in initial data reporting. Treatment algorithms that guide the use of this novel surgical modality are of benefit to practicing orthopaedic surgeons.
Subject(s)
Rotator Cuff Injuries , Rotator Cuff , Arthroplasty , Arthroscopy/methods , Humans , Rotator Cuff/surgery , Rotator Cuff Injuries/surgery , Treatment OutcomeABSTRACT
BACKGROUND: Point-of-care treatment options for medium to large symptomatic articular cartilage defects are limited. Minced cartilage implantation is an encouraging single-stage option, providing fresh viable autologous tissue with minimal morbidity and cost. PURPOSE: To determine the histological properties of mechanically minced versus minimally manipulated articular cartilage. STUDY DESIGN: Controlled laboratory study. METHODS: Remnant articular cartilage was collected from fresh femoral condylar allografts. Cartilage samples were divided into 4 groups: cartilage explants with or without fibrin glue and mechanically minced cartilage with or without fibrin glue. Samples were cultured for 42 days. Chondrocyte viability was assessed using live/dead assay. Cellular migration and outgrowth were monitored using bright-field microscopy. Extracellular matrix deposition was assessed via histological staining. Proteoglycan content and synthesis were assessed using dimethylmethylene blue assay and radiolabeled 35S-sulfate, respectively. Type II collagen (COL2A1) gene expression was analyzed via polymerase chain reaction. RESULTS: The mean viability of minced cartilage particles (34% ± 14%) was not significantly reduced compared with baseline (46% ± 13%) on day 0 (P = .90). After culture, no significant difference in the percentage of live cells was appreciated between mechanically minced (58% ± 23%) and explant (73% ± 14%) cartilage in the presence of fibrin glue (P = .52). The addition of fibrin glue did not significantly affect the viability of cartilage samples. The qualitative assessment revealed comparable cellular migration and outgrowth between groups. Proteoglycan synthesis was not significantly different between groups. Histological analysis findings were positive for COL2A1 in all groups, and matrix formation was appreciated in all groups. COL2A1 expression in minced cartilage (1.72 ± 1.88) was significantly higher than in explant cartilage (0.15 ± 0.07) in the presence of fibrin glue (P = .01). CONCLUSION: Mechanically minced articular cartilage remained viable after 42 days of culture in vitro and was comparable with cartilage explants with regard to cellular migration, outgrowth, and extracellular matrix synthesis. CLINICAL RELEVANCE: Mechanically minced articular cartilage is an encouraging intervention for the treatment of symptomatic cartilage defects. Further translational work is warranted to determine the viability of minced cartilage implantation as a single-stage therapeutic intervention in vivo.
Subject(s)
Cartilage, Articular , Cartilage, Articular/metabolism , Chondrocytes/transplantation , Fibrin Tissue Adhesive/pharmacology , Humans , Knee Joint/surgery , Proteoglycans/metabolismABSTRACT
Background: Meniscal ramp lesions are injuries of the posterior horn of the medial meniscus at the meniscocapsular junction or the meniscotibial ligament and are frequently associated with concomitant anterior cruciate ligament (ACL) injury. Objective: To review the current literature on meniscal ramp lesion management to better define the indications for and outcomes of repair. Methods: A narrative literature review was performed using PubMed, Embase, and Scopus databases. Studies of all evidence levels (I-V) pertaining to meniscal ramp lesions were reviewed and included. Results: The incidence of ramp lesions has been reported between 16% and 42%. Arthroscopy remains the diagnostic gold standard as magnetic resonance imaging has limited sensitivity. Biomechanically, ramp lesions are known to increase anterior tibial translation and rotational laxity. Clinical investigations regarding optimal management are largely limited to studies of low evidence levels. While case series have demonstrated that repair is safe and efficacious, comparative studies have failed to suggest that repair of stable lesions results in superior outcomes when compared to conservative treatment approaches. However, repair may be warranted in unstable ramp lesion injuries despite the increased risk for revision surgery. Conclusion: While there is evidence to suggest that ramp lesion repair can restore joint kinematics, the current body of clinical literature fails to suggest that outcomes following repair are superior to injuries managed conservatively. The current body of clinical literature is limited, and further robust, long-term study is warranted to better guide injury diagnosis and management protocol.
ABSTRACT
Purpose: To systematically review the literature to determine the injury mechanisms, presentation, and timing of diagnosis for pediatric patients with intratendinous rotator cuff tears and to determine the efficacy of surgical intervention for affected patients. Methods: PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Scopus were searched. Studies were included if they involved only pediatric patients, soft-tissue rotator cuff injuries managed surgically, and reported outcomes. Patient characteristics, injury mechanisms, physical examination and imaging findings, time to diagnosis, surgical technique, and treatment outcomes were extracted. Findings were descriptively analyzed with weighted means and proportions. Results: Twenty-one studies comprising 78 patients were included. The age range was 8 to 17 years and 57 were male. The supraspinatus (n = 56) was the most injured tendon. American football was the most reported sport played at the time of injury. Most patients were diagnosed within 6 months of injury via magnetic resonance imaging. Arthroscopic management was undertaken in 68 patients. Forty-six of 51 patients for whom data were available returned to sports at a range of 2.5 to 12 months postoperatively. Repair failure occurred in three patients. Conclusions: The extant literature regarding rotator cuff tears in pediatric patients is limited to reports of low methodological quality. Qualitative synthesis of this low-level literature reveals that rotator cuff tears are mostly reported in male collision sport athletes but may also occur in female athletes and/or throwing athletes. These injuries are often successfully managed via arthroscopic repair, and patients and their families can be reassured that the majority of patients return to sports following surgery. Level of Evidence: Level IV, systematic review of level IV studies.
ABSTRACT
The ability to return to sport (RTS) after articular cartilage injury is of vital importance to athletes. Discussing the likelihood of returning to sport with patients is necessary, yet patients should be informed of the heterogeneous nature of the variables associated with successful RTS and the methodologic limitations behind current RTS rate estimates. Patient-specific factors affecting RTS are numerous and, in most cases, their isolated effect on RTS rates have yet to be examined and will remain difficult to do so. The purpose of this review is to discuss current RTS rates, explore factors leading to successful RTS, and examine the variability in physical therapy protocols after cartilage procedures, including microfracture, osteochondral allograft transplantation (OCA), autologous chondrocyte implantation (ACI), and meniscal allograft transplantation (MAT). The senior author's postoperative protocols will also be presented, as with a discussion on using RTS as a metric of patient and procedural success. Overall, there is significant variation in reported RTS rates among procedures examined, and providers must continue managing patient expectations when discussing treatment options.
ABSTRACT
Focal cartilage defects of the knee are painful and difficult to treat, especially in younger patients1. Seen in up to 60% of patients who undergo knee arthroscopy2, chondral lesions are most common on the patella and medial femoral condyle3. Although the majority of lesions are asymptomatic, a variety of treatment options exist for those that are symptomatic; however, no clear gold-standard treatment has been established. In recent years, osteochondral allograft transplantation has been increasingly utilized because of its versatility and encouraging outcomes4-7. The procedure entails replacing damaged cartilage with a graft of subchondral bone and cartilage from a deceased donor. Indications for this procedure include a symptomatic, full-thickness osteochondral defect typically ≥2 cm2 in size in someone who has failed conservative management. Relative indications include patient age of <40 years and a unipolar defect8,9. Description: Osteochondral allograft transplantation requires meticulous planning, beginning with preoperative radiographs to evaluate the patient's alignment, estimate the lesion size, and aid in matching of a donor femoral condyle. The procedure begins with the patient supine and the knee flexed. A standard arthrotomy incision is performed on the operative side. Once exposure is obtained, a bore is utilized to remove host tissue from the lesion typically to a depth of 5 to 8 mm. Measurements are taken and the donor condyle is appropriately sized to match. A coring reamer is utilized to create the plug from donor tissue, which is trimmed to the corresponding depth. After marrow elements are removed via pulse lavage, the allograft plug is placed within the femoral condyle lesion through minimal force. Alternatives: Nonoperative treatment involves a reduction in high-impact activities and physical therapy. Surgical alternatives include chondroplasty, microfracture, and osteochondral autograft transplantation; however, these options are typically performed for smaller lesions (<2 cm). For larger lesions (≥2 cm), matrix-induced autologous chondrocyte implantation (MACI) can be utilized, but requires 2 surgical procedures. Rationale: Osteochondral allograft transplantation is selected against other procedures for various reasons related to patient goals, preferences, and expectations. Typically, this procedure is favored over microfracture or autograft transplantation when the patient has a large lesion. Allograft transplantation might be favored over MACI because of patient preference for a single surgical procedure instead of 2. Expected Outcomes: To our knowledge, there are currently no Level-I or II trials comparing osteochondral allograft transplantation against other treatments for cartilage defects. There are, however, many systematic reviews of case studies and cohorts that report on outcomes. A 2016 review of 291 patients showed significantly improved patient-reported outcomes at a mean follow-up of 12.3 years5,9. The mean survival of grafts was 94% at 5 years and 84% at 10 years5. Overall, data on long-term survival are lacking because interest in and use of this procedure have only increased over the past few decades10. Finally, the rate of return to sport is promising, with the systematic review by Campbell et al. showing rates as high as 88% with an average time to return to sport of 9.6 months11. Postoperatively, patients can expect to immediately begin passive range of motion. Progression of heel-touch weight-bearing begins at 6 weeks, and patients may return to sport-specific activity after 8 months, as tolerated. Important Tips: Ensure that the allograft is of adequate quality and is size-matched prior to performing the surgical procedure.The cannulated cylinder should be perpendicular to both the host lesion and graft tissue in order to ensure symmetric estimations of size.Save subchondral bone shavings when preparing the host lesion. These can be utilized to take up space if your graft depth is not sufficient to fill the host defect.Utilize saline solution irrigation judiciously when reaming out the host tissue and graft plug. Acronyms & Abbreviations: AAROM = active-assisted range of motionACI = autologous chondrocyte implantationAP = anteroposteriorBMI = body mass indexCPM = continuous passive range of motionGlut/glutes = gluteal musclesHTO = high tibial osteotomyICRS = International Cartilage Repair SocietyLFC = lateral femoral condyleLTP = lateral tibial plateauMACI = matrix-induced autologous chondrocyte implantationMFC = medial femoral condyleMobs = mobilizationMRI = magnetic resonance imagingNSAIDs = non-steroidal anti-inflammatory drugsOAT = osteochondral allograft transplantationPROM = passive range of motionQuad = quadriceps musclesROM = range of motionSLR = straight leg raise.
ABSTRACT
Peroneal tendinosis and subluxation are lifestyle-limiting conditions that can worsen if not properly diagnosed and treated. Adequate knowledge of ankle anatomy and detailed history and comprehensive physical examination is essential for diagnosis. Peroneal tendinopathy is likely to result from overuse, whereas subluxation often precipitates from forceful contraction of peroneals during sudden dorsiflexion while landing or abruptly stopping. In athletes, conservative measures remain first-line treatment of tendinopathy, but surgery is often immediately indicated in cases of recurrent symptomatic subluxation or dislocation. Surgical technique varies on the type, mechanism, and severity of injury, but most procedures have a high success rate.
Subject(s)
Ankle Injuries/diagnosis , Ankle Injuries/therapy , Joint Dislocations/diagnosis , Joint Dislocations/therapy , Orthopedic Procedures/methods , Tendon Injuries/diagnosis , Tendon Injuries/therapy , Ankle Injuries/physiopathology , Ankle Joint/anatomy & histology , Ankle Joint/physiology , Ankle Joint/physiopathology , Athletic Injuries/diagnosis , Athletic Injuries/physiopathology , Athletic Injuries/therapy , Conservative Treatment/methods , Humans , Joint Dislocations/physiopathology , Tendinopathy/diagnosis , Tendinopathy/physiopathology , Tendinopathy/therapy , Tendon Injuries/physiopathology , Tendons/anatomy & histology , Tendons/physiology , Tendons/physiopathology , Treatment OutcomeABSTRACT
Diffusion coefficient of solutes through a porous membrane media is different from diffusion coefficient through a free homogenous media. Porosity, tortuosity and the thickness of the membrane significantly affect the diffusion through a specific thickness of a membrane and therefore it is termed as effective diffusion coefficient (Deff) which is lower than the actual diffusion coefficient, D. The Deff of single or dual solutes through a porous membrane layer are well documented but not for multiple salts. Therefore, in this study, single, dual and multiple salt mixtures were passed through a flat sheet cellulose triacetate Forward Osmosis (FO) membrane to obtain a semi-empirical relationship with the Deff and its water flux. This will allow computing the structural coefficient of FO membranes. Research community have spent tremendous efforts in membrane modification to reduce the structural coefficient to improve FO process efficiency. Our finding suggests that optimising the draw solution chemistry can achieve this goal.
Subject(s)
Membranes, Artificial , Water Purification , Organic Chemicals , Osmosis , SolutionsABSTRACT
We report here the genome sequences of three newly isolated phages that infect Mycobacterium smegmatis mc2155. Phages Findley, Hurricane, and TBond007 were discovered in geographically distinct locations and are related to cluster K mycobacteriophages, with Findley being similar to subcluster K2 phages and Hurricane and TBond007 being similar to subcluster K3 phages.
ABSTRACT
Advances in pluripotent stem cell and reprogramming technologies have given us the hope of generating hematopoietic stem cells (HSCs) in culture. To succeed, greater understanding of the self-renewing HSC during human development is required. We discovered that the glycophosphatidylinositol-anchored surface protein GPI-80 defines a subpopulation of human fetal liver hematopoietic stem/progenitor cells (HSPCs) with self-renewal ability. CD34(+)CD38(lo/-)CD90(+)GPI-80(+) HSPCs were the sole population that maintained proliferative potential and an undifferentiated state in stroma coculture and engrafted in immunodeficient mice. GPI-80 expression also enabled tracking of HSPCs once they emerged from endothelium and migrated between human fetal hematopoietic niches. GPI-80 colocalized on the surface of HSPCs with Integrin alpha-M (ITGAM), which in leukocytes cooperates with GPI-80 to support migration. Knockdown of GPI-80 or ITGAM was sufficient to compromise HSPC expansion in culture and engraftment in vivo. These findings indicate that human fetal HSCs employ mechanisms used in leukocyte adhesion and migration to mediate HSC self-renewal.
Subject(s)
Amidohydrolases/metabolism , Cell Adhesion Molecules/metabolism , Embryonic Development , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , CD11b Antigen/metabolism , Cell Differentiation , Cell Lineage , Cell Proliferation , Fetus/cytology , Flow Cytometry , GPI-Linked Proteins/metabolism , Hematopoietic Stem Cell Transplantation , Humans , Immunophenotyping , Liver/cytology , Liver/embryologyABSTRACT
BACKGROUND: Neural crest cells emerge by delamination from the dorsal neural tube and give rise to various components of the peripheral nervous system in vertebrate embryos. These cells change from non-motile into highly motile cells migrating to distant areas before further differentiation. Mechanisms controlling delamination and subsequent migration of neural crest cells are not fully understood. Slit2, a chemorepellant for axonal guidance that repels and stimulates motility of trunk neural crest cells away from the gut has recently been suggested to be a tumor suppressor molecule. The goal of this study was to further investigate the role of Slit2 in trunk neural crest cell migration by constitutive expression in neural crest cells. RESULTS: We found that Slit gain-of-function significantly impaired neural crest cell migration while Slit loss-of-function favored migration. In addition, we observed that the distribution of key cytoskeletal markers was disrupted in both gain and loss of function instances. CONCLUSIONS: These findings suggest that Slit molecules might be involved in the processes that allow neural crest cells to begin migrating and transitioning to a mesenchymal type.
Subject(s)
Cell Movement/physiology , Intercellular Signaling Peptides and Proteins/metabolism , Nerve Tissue Proteins/metabolism , Neural Crest/cytology , Receptors, Immunologic/metabolism , Animals , Cell Differentiation/genetics , Cell Differentiation/physiology , Cell Movement/genetics , Cells, Cultured , Chick Embryo , Chickens , Cytoskeleton/genetics , Cytoskeleton/metabolism , In Situ Hybridization , Intercellular Signaling Peptides and Proteins/genetics , Microscopy, Video , Nerve Tissue Proteins/genetics , Receptors, Immunologic/genetics , Reverse Transcriptase Polymerase Chain Reaction , Time-Lapse Imaging , Roundabout ProteinsABSTRACT
The millions of survivors who fled from attacks to Sudanese-controlled displacement camps and the refugee camps in Chad are the living ghosts of the Darfur genocide. The 1948 Genocide Convention incorporates extermination by mass killing and elimination through forced migration as two distinct elements of genocide. Genocide scholars and public discourse emphasize extermination by killing, but they give far less explanatory attention to the elimination processes that the Genocide Convention describes as 'deliberately inflicting on the group conditions of life calculated to bring about its physical destruction'. (Article II United Nations 1948.) In Darfur, understanding the latter processes requires theoretical attention to the history of food, water, and famine and detailed methodological attention to temporal processes of displacement. We demonstrate how intentional state-led attacks on food and water massively dislodged Black Africans in Darfur from February 2003 to August 2004. The political leadership of the Sudanese state dehumanized and forcibly displaced Black Africans from their homes in Darfur to camps where they largely remain, not only through mass killings and rapes, but also by destroying life-sustaining access to food and water, leading to the genocidal elimination of group life in this region.