Elevated Lipid Metabolites in Stored Clinical OCA Media Correlate With Chondrocyte Death.

BACKGROUND: A major limitation of osteochondral allografts (OCA) is the deterioration of cartilage health associated with cell death during prolonged storage. However, little is known about the mechanisms that contribute to chondrocyte death during storage. PURPOSE/HYPOTHESIS: This study aimed to determine whether bioactive lipid metabolites accumulate in the storage media of OCA and whether they are associated with a loss of chondrocyte viability during prolonged storage. It was hypothesized that free fatty acids (FFAs) would accumulate over time in the storage media of OCA and adversely affect cartilage health during storage. STUDY DESIGN: Controlled laboratory study. METHODS: A group of 21 (n = 6-8 OCA/treatment group) fresh human hemicondylar OCA tissues and media were analyzed after 7, 28, and 68 days of prolonged cold (4°C) storage. Targeted mass spectrometry analysis was used to quantify bioactive FFAs, as well as primary (lipid hydroperoxide [ROOH]) and secondary (malondialdehyde) lipid oxidation products. Chondrocyte viability was measured using a fluorescence-based live/dead assay and confocal microscopy. RESULTS: The concentration of all targeted fatty acid metabolites in storage media was significantly increased with increased cold storage time (P < .05). ROOH was significantly higher on day 28 of cold storage. No difference in secondary ROOH products in storage media was observed. Chondrocyte viability significantly declined in both the en face and the vertical cross-sectional analysis with increased cold storage time and inversely correlated with fatty acid metabolites (P < .05). CONCLUSION: It is well established that elevated levels of certain FFAs and lipid oxidation products can alter cell function and cause cell death via lipotoxicity and other mechanisms. This work is the first to identify elevated levels of FFA metabolites and primary oxidation lipid products in the storage media from clinical OCA. The concentrations of FFA metabolites were measured at levels (>100 µM) known to induce cell death and were directly correlated with chondrocyte viability. CLINICAL RELEVANCE: These findings provide important targets for understanding why cartilage health declines during cold storage, which can be used to optimize media formulations and improve graft health.

Participation in Sports or Recreational Activities After Osteochondral Allograft Transplantation of the Talus.

BACKGROUND: Fresh osteochondral allograft (OCA) transplantation is a viable treatment option for osteochondral defects of the talus. However, sufficient data are not available on patients' participation in sports or recreational activities after the procedure. PURPOSE: To assess whether patients undergoing OCA transplantation of the talus participated in sports or recreational activities postoperatively. STUDY DESIGN: Case series; level of evidence, 4. METHODS: A total of 36 ankles in 34 patients underwent OCA transplantation of the talus. At a mean follow-up of 9.2 years, information on participation in sports or recreational activities pre- and postoperatively was obtained, as well as postoperative pain, function, and satisfaction. RESULTS: The mean age at the time of surgery was 36.1 years (range, 20.5-57.7 years), and 50% of patients were men. The mean graft size was 3.6 cm2 (range, 1-7.2 cm2) or 41.1% of the talar dome. Before the injury, 63.9% of patients (23/36 ankles) reported being highly competitive athletes or well trained and frequently sporting; 36.1% of patients (13/36 ankles) reported sometimes sporting or were nonsporting. Also, 66.7% of patients (24/36 ankles) were able to participate in sports or recreational activities after OCA transplantation and 50% (18/36 ankles) were still participating in sports or recreational activities at the latest follow-up. In a subset of well-trained or highly competitive athletes, 73.9% (17/23 ankles) were able to return to sports or recreational activities at any point after OCA transplantation, and 65.2% (15/23 ankles) were still participating at the latest follow-up. Further surgery occurred in 16.7% of patients (6/36 ankles). Graft survivorship was 94.3% at 5 years and 85.3% at 10 years. There was a significant improvement in the mean Olerud-Molander Ankle Scores, and the mean Foot and Ankle Ability Measure scores were high postoperatively. Moreover, 79.4% of patients (27/34 ankles) were either satisfied or extremely satisfied with the allograft surgery. CONCLUSION: Fresh OCA transplantation is a reasonable surgical option for osteochondral defects of the talus for young, active patients who have failed previous operative management or have massive defects.

'On Table' Versus 'Off Table' Direct Anterior Approach Total Hip Arthroplasty: Is There a Difference?

Background: The purpose of this study was to evaluate whether there were differences in patient-reported outcomes, operative times, satisfaction scores, and complications between patients undergoing total hip arthroplasty (THA) performed through a direct anterior approach on a specialized traction table or a regular operating room table. Methods: Patients who underwent a direct anterior approach THA on a specialized table or a regular table with a minimum 1-year follow-up were included. Patient-reported outcome measures and THA satisfaction were recorded. Demographics, complications, and operative times (both in-room and surgical time) were evaluated. Three hundred twenty-two patients were included with 217 (67.4%) undergoing anterior THA on the specialized table and 105 (32.6%) on a regular table. Results: Outcome measures were similar at 4 months and 1 year postoperatively. Average operative time was 87 minutes (range, 50-160) and 90 minutes (range, 35-197) for the specialized table and regular table groups (P = .314). Average total in room time was 123 minutes (range, 87-201) and 120 minutes (range, 62-255) for the specialized table and regular table groups (P = .564). Satisfaction rates between groups did not differ (P = .564). No differences were found in complication rates at 4 months (P = .814) or 1 year (P = .547). Conclusions: This study shows that the direct anterior approach for THA can be safely and efficiently performed on either a specialized traction table or a regular table. Surgeons should continue to utilize the approach and set-up they are most comfortable with to achieve an optimal outcome for the patient.

Subchondral Bone Alignment in Osteochondral Allograft Transplants for Large Oval Defects of the Medial Femoral Condyle: Comparison of Lateral versus Medial Femoral Condyle Donors.

OBJECTIVE: Supply-demand mismatch of medial femoral condyle (MFC) osteochondral allografts (OCAs) remains a rate-limiting factor in the treatment of osteochondral defects of the femoral condyle. Surface contour mapping was used to determine whether a contralateral lateral femoral condyle (LFC) versus ipsilateral MFC OCA differs in the alignment of donor:native subchondral bone for large osteochondral defects of the MFC. DESIGN: Thirty fresh-frozen human femoral condyles were matched by tibial width into 10 groups of 3 condyles (MFC recipient, MFC donor, and LFC donor) each for 3 cartilage surgeons (90 condyles). The recipient MFC was imaged using nano-computed tomography scan. Donor oval grafts were harvested from each matched condyle and transplanted into a 17 mm × 36 mm defect created in the recipient condyle. Following the first transplant, the recipient condyle was imaged and superimposed on the native condyle nano-CT scan. The donor plug was removed and the process repeated for the other donor. Surface height deviation and circumferential step-off height deviation were compared between native and donor subchondral bone surfaces for each transplant. RESULTS: There was no statistically significant difference in mean subchondral bone surface deviation (LFC = 0.87 mm, MFC = 0.76 mm, P = 0.07) nor circumferential step-off height (LFC = 0.93 mm, MFC = 0.85 mm, P = 0.09) between the LFC and MFC plugs. There were no significant differences in outcomes between surgeons. CONCLUSIONS: There were no significant differences in subchondral bone circumferential step-off or surface deviation between ipsilateral MFC and contralateral LFC oval-shaped OCAs for 17 mm × 36 mm defects of the MFC.

Osteochondral Allografts for Large Oval Defects of the Medial Femoral Condyle: A Comparison of Single Lateral Versus Medial Femoral Condyle Oval Grafts Versus 2 Overlapping Circular Grafts.

BACKGROUND: Studies have demonstrated the acceptability of using a contralateral nonorthotopic lateral femoral condyle (LFC) graft for a circular medial femoral condyle (MFC) osteochondral defect up to 20 to 25 mm in diameter. Larger oblong defects can now be managed using either overlapping circle grafts or a single oblong-shaped osteochondral allograft (OCA). PURPOSE: To determine if an oblong contralateral nonorthotopic LFC OCA can attain an acceptable surface contour match compared with an oblong ipsilateral MFC OCA or an overlapping circle technique for large oblong defects of the MFC. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 120 fresh-frozen human femoral condyles were matched by tibial width into 30 groups of 4 condyles (1 recipient MFC, 3 donor condyles). The recipient MFC was initially imaged using nano-computed tomography (nano-CT). A 17 × 36-mm oblong defect was created in the recipient MFC. Overall, 3 donor groups were formed: MFC oblong, LFC nonorthotopic oblong, LFC or MFC overlapping circles. After each transplant, the recipient condyle underwent nano-CT and was digitally reconstructed, which was superimposed on the initial nano-CT scan of the native recipient condyle. Dragonfly 3D software was used to determine the root mean square (RMS) of both the surface height deviation and the circumferential step-off height deviation between the native and donor cartilage surfaces for each graft. RESULTS: RMS surface height deviations were as follows: 0.59 mm for MFC oblong grafts, 0.58 mm for LFC oblong grafts, and 0.78 mm for overlapping circle grafts. The MFC and LFC oblong grafts had significantly less surface height deviation than the overlapping circle grafts (P = .004 and P = .002, respectively). RMS step-off height deviations were as follows: 0.68 mm for MFC oblong grafts, 0.70 mm for LFC oblong grafts, and 0.85 mm for overlapping circle grafts. The MFC and LFC oblong grafts had significantly less step-off height deviation than the overlapping circle grafts (P < .001 and P = .002, respectively). The majority of this difference was on the medial segment of the overlapping circle grafts. CONCLUSION: Oblong ipsilateral MFC OCAs and oblong contralateral nonorthotopic LFC OCAs produced a significantly better surface contour match to the native MFC than overlapping circle grafts for oblong defects 17 × 36 mm in size. CLINICAL RELEVANCE: Size-matched contralateral nonorthotopic LFC grafts are acceptable for MFC defects, which may allow for a quicker match, earlier patient care, and less wastage of valuable donor tissue.

Are immediate postoperative X-Rays valuable in evaluating complications of primary total hip arthroplasty?

PURPOSE: This study aimed to investigate the complications of primary total hip arthroplasty based on immediate postoperative X-rays. The overall quality and cost of X-rays were assessed. METHODS: The institutional database was queried to identify all patients who underwent total hip arthroplasty in a single institution between January 1, 2018, and December 31, 2018. Immediate postoperative X-rays were reviewed to identify the complications such as periprosthetic fractures, dislocation, and fixation failure. The quality and cost of X-ray were assessed. The complications were categorized as "known" and "unknown" according to the intraoperative fluoroscopic results. RESULTS: A total of 518 total hip arthroplasties were included in this study. Based on intraoperative fluoroscopy, periprosthetic fractures were found in 10 (2%) THAs. Compared to the X-rays taken immediately after surgery, 9 periprosthetic fractures (recorded as "known") were found and 1 was not (recorded as "unknown"). There was no significant difference between intraoperative fluoroscopy and X-rays (P > 0.05). Of the 518 X-rays, 225 (43%) were of suboptimal quality. The cost of a single portable pelvic X-ray was $647. CONCLUSION: In total hip arthroplasty, X-rays taken immediately after surgery rarely reveal unknown complications. The X-rays are often of suboptimal quality, have minimal clinical utility, and are less cost-effective.

Hip and Knee Arthroplasty Outcomes for Nonagenarian Patients.

INTRODUCTION: Studies have previously reported higher complication rates in elective total joint arthroplasty (TJA) for nonagenarians compared with younger cohorts. The purpose of this study was to assess whether nonagenarians were still at increased risk of complications and hospital readmissions by answering three questions: (1) Do nonagenarians have an increased risk of medical complications after TJA compared with octogenarians and septuagenarians? (2) Do nonagenarians have an increased risk of surgical complications after TJA compared with octogenarians and septuagenarians? (3) Do nonagenarians have an increased risk of hospital readmission after TJA compared with octogenarians and septuagenarians? METHODS: A total of 174 patients undergoing primary TJA between 2010 and 2017 were included; 58 nonagenarians (older than 90 years) were matched with 58 octogenarians (age 80 to 84 years) and 58 septuagenarians (age 70 to 74). Groups were matched by sex, diagnosis, surgeon, surgical joint, and year of surgery. Within each group, 31 patients (53%) underwent total hip arthroplasty and 27 patients (47%) underwent total knee arthroplasty. Comorbidities, American Society of Anesthesiologists physical status scores, and Charlson Comorbidity Index scores were captured preoperatively. Complications and readmissions occurring within 90 days postoperatively were evaluated. RESULTS: Nonagenarians had the highest rate of medical complications (33%) compared with octogenarians (14%) and septuagenarians (3%) (P < 0.001). Rates of surgical complications were not statistically different among nonagenarians (12%), octogenarians (9%), and septuagenarians (10%) (P = 0.830). Rates of hospital readmission were highest in nonagenarian patients (11%), but not statistically different compared with octogenarians (5%) or septuagenarians (2%) (P = 0.118). CONCLUSION: Nonagenarians were 3.1 times more likely to have a complication after TJA. The incidence of medical complications was highest in nonagenarians compared with octogenarians and septuagenarians, but rates of orthopaedic complications were similar. Nonagenarians who elect to proceed with TJA should be informed that they have an increased risk of postoperative medical complications compared with younger patients undergoing the same operation. LEVEL OF EVIDENCE: Level III, Therapeutic Study.

Inconsistent Reporting of Preauthorization Medical Criteria for Osteochondral Allograft Transplantation Surgery.

BACKGROUND: Although osteochondral allograft (OCA) transplantation has been a standard treatment for patients with osteochondral lesions, there is a disagreement in commercial payers' medical criteria regarding the definition of medical suitability and thus authorization for OCA transplantation. The primary goal of this study was to understand where consensus between a committee of experienced cartilage restoration surgeon scientists and payer policies existed and where there was significant disagreement. METHODS: U.S. private payers were identified by reviewing health insurance market research literature. Medical criteria were then obtained from publicly available payer medical polices. A literature review was conducted to identify supporting evidence for consensus statements based on private payer medical criteria. The MOCA (Metrics of Osteochondral Allograft) Committee, 30 experienced surgeons and subject-matter experts in OCA transplantation, used a Likert scale of 1 (strongly disagree) to 5 (strongly agree) to rank each statement. The extent of agreement and disagreement among participants was measured for each statement. Consensus was defined as agreement or disagreement of >75%. RESULTS: Fifty-seven statements regarding relevant medical criteria for OCA transplantation were included in the survey. All 30 MOCA Committee members completed the survey (100% response rate). Over half of the statements (52.6%) did not reach consensus. Of the remaining 27 statements that reached consensus, respondents agreed or strongly agreed with 16 statements, and disagreed or strongly disagreed with 11 statements. Inconsistent voting was observed for statements related to osteoarthritis, inflammation, and degenerative changes. CONCLUSIONS: Commercial payers are not consistent in the medical criteria used to define patient eligibility for authorization of OCA transplantation. In contrast, an expert panel of cartilage surgeons reached a consensus that OCA transplantation was clearly suitable for a variety of specific indications. This study demonstrates the need to standardize medical criteria for cartilage restoration based on the most current literature, as well as in conjunction with experienced cartilage restoration experts. LEVEL OF EVIDENCE: Therapeutic Level V . See Instructions for Authors for a complete description of levels of evidence.

No Difference in Blood Loss and Risk of Transfusion Between Patients Treated with One or Two Doses of Intravenous Tranexamic Acid After Simultaneous Bilateral TKA.

BACKGROUND: Tranexamic acid (TXA) is often used to prevent excessive blood loss during bilateral TKA. Although it diminishes blood loss, TXA may have a potentially elevated thrombogenic risk with extra, unnecessary doses of TXA in this high-risk population. To date, the most efficacious dosing protocol in this setting has not yet been ascertained. QUESTIONS/PURPOSES: We compared one versus two doses of intravenous TXA in the setting of same-day bilateral TKA in terms of (1) perioperative blood loss that occurred during the hospital stay, (2) transfusion usage during the hospital stay, and (3) major complications occurring within 30 days of surgery. METHODS: Between August 2013 and October 2016, 309 patients underwent simultaneous bilateral TKA performed by one of five attending surgeons. During that time, indications for same-day bilateral TKA included bilateral knee pathology in which each knee was independently indicated for TKA and the patient preferred bilateral simultaneous TKAs versus staged bilateral surgeries. Patients who had cardiac disease or an American Society for Anesthesiologists physical classification score of greater than 2 were not generally indicated for bilateral simultaneous TKAs. After preoperative clearance from the primary physician and/or specialists as necessary, the decision for bilateral TKA was at the judgment of the operating surgeons. Input from anesthesia occurred at the time of the surgery as the procedure was performed in a sequential fashion allowing for the surgery to be restrained to a single limb if anesthesia identified concerns at the completion of the first TKA. The current retrospective, comparative series compared generally sequential groups in terms of TXA usage. Between August 2013 and July 2015, we used two TXA doses. Patients received 1 g of intravenous TXA as a bolus immediately after the last tourniquet release and were given a 1-g intravenous bolus 6 hours after the initial dose. A total of 167 patients were treated with this approach, of whom 96% (161) are fully analyzed here. Between August 2015 and October 2016, our approach changed to a single TXA dose. The dosing regimen change occurred as a group decision for change of practice and occurred mid-year to coincide with the fellowship year cycle. Patients received a 1-g bolus of intravenous TXA immediately after the final tourniquet release. A total of 105 patients were treated with this approach, of whom 89% (93) are fully analyzed here. An additional 37 patients were excluded because they did not receive any TXA because of a medical contraindication such as history of venous thromboembolism, history of thrombotic stroke, cardiac stent in the past 2 years, atrial fibrillation, or long-term anticoagulation therapy. We compared patients who received one versus two doses in terms of blood loss, transfusion usage, and 30-day major complications. The mean age was 65 years for patients receiving one dose and 67 years for patients receiving two doses (p = 0.17). The one-dose group comprised 67% (62 of 93) women and the two-dose group comprised 61% (98 of 161) women (p = 0.36). Blood loss was defined as change in the hemoglobin level (the last recorded value before discharge subtracted from the preoperative value). During the study period, the decision to transfuse was based on a hemoglobin level less than 8.0 g/dL or at higher levels for symptomatic patients, patients with cardiac disease, or at the discretion of the attending surgeon. We defined complications as major medical events that included cerebrovascular accidents, myocardial infarction, deep vein thrombosis, and pulmonary embolism. RESULTS: With the numbers available, there was no difference in blood loss between patients treated with one and those treated with two doses of TXA (mean hemoglobin decrease -3.5 ± 1.2 g/dL versus -3.5 ± 1.0 g/dL, respectively; mean difference 0.03 g/dL [95% CI -0.2 to 0.3 g/dL]; p = 0.80). No patient in either group received a transfusion. There was no difference in the proportion of patients in either group who experienced a cerebrovascular accident (0% [0 of 93] versus 1% [1 of 161]; p > 0.99), deep vein thrombosis (1% [1 of 93] versus 0% [0 of 161]; p = 0.37), or pulmonary embolism (1% [1 of 93] versus 1% [1 of 161]; p > 0.99). No patient in either the one-dose or two-dose TXA groups experienced a myocardial infarction. CONCLUSION: The findings of this study suggest that a single dose of intravenous TXA may be adequate to control excessive blood loss and reduce blood transfusion in simultaneous bilateral TKA. Despite its short half-life, TXA still appears to be effective in this demanding procedure without requiring prolonged plasma concentrations obtained from multiple doses. Additional high-quality studies are still needed to determine the most appropriate dosing regimen. LEVEL OF EVIDENCE: Level III, therapeutic study.

Direct Anterior Approach to Total Hip Arthroplasty Improves the Likelihood of Return to Previous Recreational Activities Compared with Posterior Approach.

Total hip arthroplasty offers relief and functional improvement, with the rate of direct anterior approach (DAA) increasing compared with the posterior approach (PA). This study aimed to assess the effect of surgical approach on return to recreational activity after total hip arthroplasty. Total hip arthroplasty performed for primary or posttraumatic osteoarthritis were identified; 100 DAA patients were matched with 100 PA patients on age, sex, diagnosis, and surgical year. Patients were mailed a recreational activity survey, Harris Hip Function, and Hip disability and Osteoarthritis Outcome Score questionnaires. Two hundred surveys were mailed, 130 (65%) responded (66 DAA and 64 PA) and were included. The mean follow-up was 2.5 years for the DAA group and 2.3 years for the PA group (P = 0.256). Among DAA patients, 51% returned to activity within 6 months, compared with 44% of PA patients (P = 0.360). Among those who returned to activity, 71% in the DAA group tried their main presurgery sport, compared with 53% in the PA group (P = 0.019). Twenty-eight percent of DAA patients and 4% of PA patients reported the surgical approach influenced their return to activity (P = 0.001). Outcome scores were clinically similar between groups. Objective data did not favor one approach over the other.

Fresh Osteochondral and Chondral Allograft Preservation and Storage Media: A Systematic Review of the Literature.

BACKGROUND: Storage procedures and parameters have a significant influence on the health of fresh osteochondral allograft (OCA) cartilage. To date, there is a lack of agreement on the optimal storage conditions for OCAs. PURPOSE: To systematically review the literature on (1) experimental designs and reporting of key variables of ex vivo (laboratory) studies, (2) the effects of various storage solutions and conditions on cartilage health ex vivo, and (3) in vivo animal studies and human clinical studies evaluating the effect of fresh OCA storage on osteochondral repair and outcomes. STUDY DESIGN: Systematic review; Level of evidence, 5. METHODS: A systematic review was performed using the PubMed, Embase, and Cochrane databases. The inclusion criteria were laboratory studies (ex vivo) reporting cartilage health outcomes after prolonged storage (>3 days) of fresh osteochondral or chondral tissue explants and animal studies (in vivo) reporting outcomes of fresh OCA. The inclusion criteria for clinical studies were studies (>5 patients) that analyzed the relationship of storage time or chondrocyte viability at time of implantation to patient outcomes. Frozen, cryopreserved, decellularized, synthetic, or tissue-engineered grafts were excluded. RESULTS: A total of 55 peer-reviewed articles met the inclusion criteria. Ex vivo studies reported a spectrum of tissue sources and storage solutions and conditions, although the majority of studies lacked complete reporting of key variables, including storage solution formula and environmental conditions. The effect of various conditions (eg, temperature) and storage solutions on cartilage health were inconsistent. Although 60% of animal models suggest that storage time may influence outcomes and 80% indicate inferior outcomes with frozen OCA as compared with fresh OCA, 75% of clinical studies report no correlation between storage time and outcomes. CONCLUSION: Given the variability in experimental designs and lack of reporting across studies, it is still not possible to determine optimal storage conditions, although animal studies suggest that storage time and chondrocyte viability influence osteochondral repair outcomes. A list of recommendations was developed to encourage reporting of key variables, such as media formulation, environmental factors, and methodologies used. High-quality clinical data are needed to investigate the effects of storage and graft health on outcomes.

A Systematic Review of Focal Cartilage Defect Treatments in Middle-Aged Versus Younger Patients.

BACKGROUND: Focal cartilage defects are often debilitating, possess limited potential for regeneration, are associated with increased risk of osteoarthritis, and are predictive for total knee arthroplasty. Cartilage repair studies typically focus on the outcome in younger patients, but a high proportion of treated patients are 40 to 60 years of age (ie, middle-aged). The reality of current clinical practice is that the ideal patient for cartilage repair is not the typical patient. Specific attention to cartilage repair outcomes in middle-aged patients is warranted. PURPOSE: To systematically review available literature on knee cartilage repair in middle-aged patients and include studies comparing results across different age groups. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic search was performed in EMBASE, MEDLINE, and the Cochrane Library database. Articles were screened for relevance and appraised for quality. RESULTS: A total of 21 articles (mean Coleman Methodology Score, 64 points) were included. Two out of 3 bone marrow stimulation (BMS) studies, including 1 using the microfracture technique, revealed inferior clinical outcomes in middle-aged patients in comparison with younger patients. Nine cell-based studies were included showing inconsistent comparisons of results across age groups for autologous chondrocyte implantation (ACI). Bone marrow aspirate concentrate showed age-independent results at up to 8 years of follow-up. A negative effect of middle age was reported in 1 study for both ACI and BMS. Four out of 5 studies on bone-based resurfacing therapies (allografting and focal knee resurfacing implants [FKRIs]) showed age-independent results up to 5 years. One study in only middle-aged patients reported better clinical outcomes for FKRIs when compared with biological repairs. CONCLUSION: Included studies were heterogeneous and had low methodological quality. BMS in middle-aged patients seems to only result in short-term improvements. More research is warranted to elucidate the ameliorating effects of cell-based therapies on the aging joint homeostasis. Bone-based therapies seem to be relatively insensitive to aging and may potentially result in effective joint preservation. Age subanalyses in cohort studies, randomized clinical trials, and international registries should generate more evidence for the large but underrepresented (in terms of cartilage repair) middle-aged population in the literature.

Metrics of OsteoChondral Allografts (MOCA) Group Consensus Statements on the Use of Viable Osteochondral Allograft.

BACKGROUND: Osteochondral allograft (OCA) transplantation has evolved into a first-line treatment for large chondral and osteochondral defects, aided by advancements in storage protocols and a growing body of clinical evidence supporting successful clinical outcomes and long-term survivorship. Despite the body of literature supporting OCAs, there still remains controversy and debate in the surgical application of OCA, especially where high-level evidence is lacking. PURPOSE: To develop consensus among an expert group with extensive clinical and scientific experience in OCA, addressing controversies in the treatment of chondral and osteochondral defects with OCA transplantation. STUDY DESIGN: Consensus statement. METHODS: A focus group of clinical experts on OCA cartilage restoration participated in a 3-round modified Delphi process to generate a list of statements and establish consensus. Questions and statements were initially developed on specific topics that lack scientific evidence and lead to debate and controversy in the clinical community. In-person discussion occurred where statements were not agreed on after 2 rounds of voting. After final voting, the percentage of agreement and level of consensus were characterized. A systematic literature review was performed, and the level of evidence and grade were established for each statement. RESULTS: Seventeen statements spanning surgical technique, graft matching, indications, and rehabilitation reached consensus after the final round of voting. Of the 17 statements that reached consensus, 11 received unanimous (100%) agreement, and 6 received strong (80%-99%) agreement. CONCLUSION: The outcomes of this study led to the establishment of consensus statements that provide guidance on surgical and perioperative management of OCAs. The findings also provided insights on topics requiring more research or high-quality studies to further establish consensus and provide stronger evidence.

Long-Term Retrospective Follow-Up of Fresh Osteochondral Allograft Transplantation for Steroid-Associated Osteonecrosis of the Femoral Condyles.

OBJECTIVE: No studies currently exist with long-term follow-up of use of osteochondral allografting (OCA) for treatment of steroid-associated osteonecrosis of femoral condyles in young, active patients who wish to avoid total knee arthroplasty (TKA). We evaluate the extent to which fresh osteochondral allografts can (1) prevent or postpone need for prosthetic arthroplasty and (2) maintain long-term clinically meaningful decrease in pain and improvement in function at mean 11-year follow-up. DESIGN: Twenty-five patients (33 knees) who underwent OCA transplantation for osteonecrosis of the knee between 1984 and 2013 were evaluated, including 22 females and 11 males with average age of 25 years (range, 16-48 years). Mean total allograft surface area was 10.6 cm2 (range, 4.0-19.0 cm2). Evaluation included International Knee Documentation Committee (IKDC) scores, Knee Society function (KS-F) score, and modified (for the knee) Merle d'Aubigné-Postel (18-point) score. RESULTS: OCA survivorship was 90% at 5 years and 82% at 10 years. Twenty-eight of 33 knees (85%) avoided arthroplasty and 25 of 33 knees (73%) avoided other surgical intervention. Mean IKDC pain score improved (P = 0.001) from 7.2 preoperatively to 2.8 at latest follow-up, mean IKDC function score increased (P = 0.005) from 3.3 to 6.5, and mean IKDC total score improved (P = 0.001) from 31.9 to 61.1. Mean KS-F score improved (P = 0.003) from 61.7 to 87.5. Mean modified Merle d'Aubigné-Postel (18-point) score improved (P < 0.001) from 11.4 to 15.1. CONCLUSIONS: Our findings suggest that OCA transplantation is a reasonable surgical treatment option for steroid-associated osteonecrosis of the femoral condyles, with durable long-term outcomes.

Single Use Instruments for Implanting a Contemporary Total Knee Arthroplasty System Are Accurate, Efficient, and Safe.

BACKGROUND: Single use instruments (SUI) is a potential mechanism to improve efficiency and reduce cost in total knee arthroplasty (TKA). New technology requires patient safety and surgical accuracy. A multi-center study of SUI vs reusable mechanical instrumentation (RUI) for a TKA system compared implant placement accuracy and operating room (OR) efficiency. METHODS: Four surgeons implanted 88 primary TKAs, N = 44 RUI and N = 44 SUI. Accuracy was measured radiographically at 3 months. The primary endpoint was non-inferiority of absolute value of mechanical axis alignment. Radiographic endpoints, OR times, and adverse events were also evaluated. RESULTS: Seventy-five subjects completed the study (41 SUI/34 RUI). The primary endpoint non-inferiority of SUI vs RUI was met, with no significant difference between SUI and RUI in most radiographic parameters (distal femoral varus-valgus, proximal tibial varus-valgus, tibial slope, or subjects within 3° of target); there was a slight difference in femoral component flexion angle (P = .015). SUI and RUI mean (SD) OR set-up times were 18.8 (10.03) and 26.7 (6.93) (P <.001), and surgical times (first incision to last stitch) were 64.6 (16.95) and 60.5 (19.01) (P = .295), respectively. Differences in OR clean-down and anesthesia were not significant. There were no revisions, and there was no significant difference in the number of reported adverse events. CONCLUSION: SUI resulted in similar accuracy of implant placement to RUI with decreased OR set-up time and no increase in adverse events. These results support the safety and efficacy of SUI for performing TKA. Further analysis of potential economic and technical advantages is warranted.

Aspirin used for venous thromboembolism prophylaxis in total hip arthroplasty decreases heterotopic ossification.

BACKGROUND: Heterotopic ossification (HO) is a known complication of total hip arthroplasty (THA) that can lead to persistent pain, stiffness, nerve impingement, and instability. Aspirin (ASA) has become an increasingly popular method of venous thromboembolism (VTE) prophylaxis, given its availability, ease of use, and relative safety. Although indomethacin has been commonly used for HO prophylaxis, we wanted to determine whether ASA, given the similar mechanism of action, may be effective in reducing the risk of HO in routine unilateral, primary THA when already being used for VTE prophylaxis. METHODS: The postoperative radiographs of 222 consecutive patients undergoing unilateral, primary THA with cementless fixation were evaluated for HO formation using the Brooker classification immediately before and after surgeon protocol shifted to routine utilization of ASA as VTE prophylaxis in low-risk patients. RESULTS: HO was detected in 13 of 99 (13.1%) THAs prescribed ASA for VTE prophylaxis (11 grade I, 1 grade II, 1 grade III) compared with 38 of 123 (30.9%) THAs prescribed non-ASA chemoprophylaxis (26 grade I, 7 grade II, 4 grade III, 1 grade IV). Significantly more THAs in the non-ASA cohort developed HO (P < .01). There was no significant difference in the distribution of HO severity between cohorts (P = .61). CONCLUSIONS: ASA may be effective as monotherapy for both VTE and HO reduction in low-risk patients undergoing unilateral primary arthroplasty with cementless fixation.

An Expert Consensus Statement on the Management of Large Chondral and Osteochondral Defects in the Patellofemoral Joint.

BACKGROUND: Cartilage lesions of the patellofemoral joint constitute a frequent abnormality. Patellofemoral conditions are challenging to treat because of complex biomechanics and morphology. PURPOSE: To develop a consensus statement on the functional anatomy, indications, donor graft considerations, surgical treatment, and rehabilitation for the management of large chondral and osteochondral defects in the patellofemoral joint using a modified Delphi technique. STUDY DESIGN: Consensus statement. METHODS: A working group of 4 persons generated a list of statements related to the functional anatomy, indications, donor graft considerations, surgical treatment, and rehabilitation for the management of large chondral and osteochondral defects in the patellofemoral joint to form the basis of an initial survey for rating by a group of experts. The Metrics of Osteochondral Allografts (MOCA) expert group (composed of 28 high-volume cartilage experts) was surveyed on 3 occasions to establish a consensus on the statements. In addition to assessing agreement for each included statement, experts were invited to propose additional statements for inclusion or to suggest modifications of existing statements with each round. Predefined criteria were used to refine statement lists after each survey round. Statements reaching a consensus in round 3 were included within the final consensus document. RESULTS: A total of 28 experts (100% response rate) completed 3 rounds of surveys. After 3 rounds, 36 statements achieved a consensus, with over 75% agreement and less than 20% disagreement. A consensus was reached in 100.00% of the statements relating to functional anatomy of the patellofemoral joint, 88.24% relating to surgical indications, 100.00% relating to surgical technical aspects, and 100.00% relating to rehabilitation, with an overall consensus of 95.5%. CONCLUSION: This study established a strong expert consensus document relating to the functional anatomy, surgical indications, donor graft considerations for osteochondral allografts, surgical technical aspects, and rehabilitation concepts for the management of large chondral and osteochondral defects in the patellofemoral joint. Further research is required to clinically validate the established consensus statements and better understand the precise indications for surgery as well as which techniques and graft processing/preparation methods should be used based on patient- and lesion-specific factors.

Osteochondritis Dissecans Lesion Location Is Highly Concordant With Mechanical Axis Deviation.

BACKGROUND: The cause of osteochondritis dissecans (OCD) is unknown. PURPOSE: To determine if mechanical axis deviation correlates with OCD lesion location in the knee, if degree of mechanical axis deviation correlates with size of OCD lesion, and if the deformity was primarily in the distal femur or proximal tibia. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: We identified 61 knees that underwent osteochondral allograft (OCA) transplantation for femoral condyle OCD lesions and used preoperative lower extremity alignment radiographs to measure lower extremity mechanical axis, mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and hip-knee-ankle angle. Lesion location and area were retrieved from operative records. RESULTS: The location of the OCD lesion was the medial femoral condyle (MFC) for 37 knees and lateral femoral condyle (LFC) for 24 knees. Among knees with MFC lesions, alignment was varus in 25 (68%). Conversely, knees with LFC lesions had valgus alignment in 16 (67%). The mLFDA was significantly more valgus in the LFC group. mMPTA was not different between MFC and LFC groups. There was no significant correlation between degree of mechanical axis deviation and lesion size. CONCLUSION: In this cohort, two-thirds of patients with symptomatic OCD lesions had associated mechanical axis deviation. Lesion location correlated with mechanical axis deviation (LFC lesions were associated with a deformity in the distal femur). Degree of deformity was not correlated with lesion size. Mechanical axis deviation may play a role in OCD pathogenesis. These data do not allow analysis of the role of mechanical axis deviation in causation or prognosis of OCD lesions, but surgeons treating OCD should be aware of this common association.

Editorial Commentary: Revising a Failed Osteochondral Allograft-Further Down the Rabbit Hole We Go .

Fresh osteochondral allografting has gained popularity as a useful technique for managing difficult cartilage repair problems and, in revision situations, is a treatment of choice when other procedures such as microfracture, osteochondral autograft transfer, and cell-based therapies fail. However, it is a challenge when an allograft fails. Absent substantial progression of osteoarthritis, revising with another allograft results in a reasonable chance of "success" (but a high likelihood of further surgery along the way). Thus, in the setting of a failed osteochondral allograft, sometimes the best option is to keep going further down the rabbit hole and revise a failed allograft with an allograft.

Self-Reported Metal Allergy and Early Outcomes After Total Knee Arthroplasty.

The impact of self-reported metal allergy (SRMA) in total knee arthroplasty (TKA) remains controversial. In the absence of objective tests, SRMA is often used as a screening tool for implant selection. The objective of this study was to determine the effect of SRMA on early outcomes after TKA. Between 2010 and 2014, 168 patients with SRMA underwent TKA; 150 (89%) received nickel-free implants, and 18 (11%) received cobalt-chrome implants that contained nickel. Mean age was 67 years, and 95% were female. A cohort of 858 TKA patients (mean age, 68 years) without SRMA matched by sex served as the control group. Outcomes included Knee Society Score (function [KSS-F] and knee [KSS-K]), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, knee flexion, further surgery, and complications. No differences were seen in KSS-F and KSS-K between patients with and without SRMA. The mean WOMAC pain scores were 89.1 for patients with SRMA and 85.2 for patients without SRMA (P=.030). Stiffness and physical function scores were similar. Knee flexion was similar. No differences were found between nickel-free and cobalt-chrome SRMA groups. Patients with SRMA and those without demonstrated similar early functional outcomes. Patients with SRMA who received standard cobalt-chrome implants had no significant difference in functional outcomes compared with patients with nickel-free implants. Better identifiers of patients at risk for adverse events due to implant material are needed. [Orthopedics. 2019; 42(6):330-334.].