Osteochondral Allograft Transplantation Research Articles

Understanding the difference between symptoms of focal cartilage defects and osteoarthritis of the knee: a matched cohort analysis.

Comparing symptoms of patients with focal cartilage defects of the knee to those with knee osteoarthritis. Prospectively maintained databases identified patients with focal cartilage defects (FCD group) who underwent osteochondral allograft transplantation and patients with osteoarthritis (OA group) undergoing arthroplasty. Patients between 18 and 55 years of age were included and matched based on age. Baseline patient demographics, symptoms, and patient-reported outcomes including the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR), SF-12, and VR-12 questionnaires were recorded. Patient symptoms and individual responses of the KOOS JR were compared between groups. Regression analysis was used to evaluate the association between pre-operative factors that significantly differed between groups and the KOOS JR questionnaire. Sixty-four patients were included: 32 patients in each group. The FCD group had a significantly lower body mass index (BMI) (p = 0.04) and greater number of workers' compensation cases (p = 0.027) when compared to the OA group. Patients in the OA group complained more frequently of medial-sided pain (p = 0.02) and knee swelling (p = 0.003). The OA cohort also had greater pain with fully straightening the knee (p = 0.012), pain with standing upright (p = 0.016), and pain with rising from sitting (p = 0.003). Patients in the FCD group had greater KOOS JR outcome scores (51.5 ± 12.9 vs. 41.5 ± 20.5; p = 0.023). When compared to patients with focal cartilage defects, adults with knee osteoarthritis scheduled for knee arthroplasty have a more severe presentation of symptoms, particularly medial-sided pain, swelling of the knee, pain associated with straightening the knee, standing upright, and rising from sitting.

Systematic Review of Osteochondral Allograft Transplant Immunology: How We Can Further Optimize Outcomes.

Despite the growing success for osteochondral allograft (OCA) transplantation in treating large articular cartilage lesions in multiple joints, associated revision and failure rates are still higher than desired. While immunorejection responses have not been documented, the effects of the host's immune responses on OCA transplantation failures have not been thoroughly characterized. The objective of this study was to systematically review clinically relevant peer-reviewed evidence pertaining to the immunology of OCAs to elucidate theragnostic strategies for improving functional graft survival and outcomes for patients undergoing OCA transplantation. This systematic review of Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, MEDLINE, PubMed, and EMBASE suggests that host immune responses play key roles in incorporation and functional survival of OCA transplants. OCA rejection has not been reported; however, graft integration through creeping substitution is reliant on host immune responses. Prolonged inflammation, diminished osteogenic potential for healing and incorporation, and relative bioburden are mechanisms that may be influenced by the immune system and contribute to undesirable outcomes after OCA transplantation. Based on the safety and efficacy of OCA transplantation and its associated benefits to a large and growing patient population, basic, preclinical, and clinical osteoimmunological studies on OCA transplantation that comprehensively assess and correlate cellular, molecular, histologic, biomechanical, biomarkers, diagnostic imaging, arthroscopic, functional, and patient-reported outcome measures are of high interest and importance.

Return to Sport After Large Single-Surface, Multisurface, or Bipolar Osteochondral Allograft Transplantation in the Knee Using Shell Grafts.

Background:Return to sport (RTS) after osteochondral allograft (OCA) transplantation for large unipolar femoral condyle defects has been consistent, but many athletes are affected by more severe lesions.Purpose:To examine outcomes for athletes who have undergone large single-surface, multisurface, or bipolar shell OCA transplantation in the knee.Study Design:Case series; Level of evidence, 4.Methods:Data from a prospective OCA transplantation registry were assessed for athletes who underwent knee transplantation for the first time (primary transplant) between June 2015 and March 2018 for injury or overuse-related articular defects. Inclusion criteria were preinjury Tegner level ≥5 and documented type and level of sport (or elite unit active military duty); in addition, patients were required to have a minimum of 1-year follow-up outcomes, including RTS data. Patient characteristics, surgery type, Tegner level, RTS, patient-reported outcome measures (PROMs), compliance with rehabilitation, revisions, and failures were assessed and compared for statistically significant differences.Results:There were 37 included athletes (mean age, 34 years; range, 15-69 years; mean body mass index, 26.2 kg/m2; range, 18-35 kg/m2) who underwent large single-surface (n = 17), multisurface (n = 4), or bipolar (n = 16) OCA transplantation. The highest preinjury median Tegner level was 9 (mean, 7.9 ± 1.7; range, 5-10). At the final follow-up, 25 patients (68%) had returned to sport; 17 (68%) returned to the same or higher level of sport compared with the highest preinjury level. The median time to RTS was 16 months (range, 7-26 months). Elite unit military, competitive collegiate, and competitive high school athletes returned at a significantly higher proportion (P < .046) than did recreational athletes. For all patients, the Tegner level at the final follow-up (median, 6; mean, 6.1 ± 2.7; range, 1-10) was significantly lower than that at the highest preinjury level (P = .007). PROMs were significantly improved at the final follow-up compared with preoperative levels and reached or exceeded clinically meaningful differences. OCA revisions were performed in 2 patients (5%), and failures requiring total knee arthroplasty occurred in 2 patients (5%), all of whom were recreational athletes. Noncompliance was documented in 4 athletes (11%) and was 15.5 times more likely (P = .049) to be associated with failure or a need for revision than for compliant patients.Conclusion:Large single-surface, multisurface, or bipolar shell OCA knee transplantations in athletes resulted in two-thirds of these patients returning to sport at 16 to 24 months after transplantation. Combined, the revision and failure rates were 10%; thus, 90% of patients were considered to have successful 2- to 4-year outcomes with significant improvements in pain and function, even when patients did not RTS.

Changes in knee range of motion after large osteochondral allograft transplantations

BackgroundOur study purpose was to determine if primary osteochondral allograft (OCA) transplant surgeries for large (>4 cm2) single-surface, multisurface, or bipolar articular defects in the knee would be associated with significant gains in knee range of motion (ROM) at ≥1-year follow-up when compared to preoperative ROM. MethodsPatients were prospectively enrolled into a dedicated registry to follow outcomes after OCA with or without meniscal allograft transplantation using Missouri Osteochondral Preservation System (MOPS)-preserved allografts. Patients were included if they had surgery to repair at least one osteochondral defect, and when at least one year of ROM data and Visual Analog Scale pain scores were available. Data on complications and reoperations, patient-reported outcome measures, compliance with rehabilitation, revisions, or failures were recorded. ResultsFor patients who met inclusion criteria after OCA surgery (n = 75), overall ROM increased from 127.8 ± 17 degrees preoperatively, to 130.5 ± 14 post-operatively. Non-compliance was the largest factor contributing to postoperative ROM lag or loss. Knee manipulation/lysis of adhesion rates were comparable to rates in TKA and ACL procedures (2.96–4.54% for ACL/TKA, 4% for OCAs in the present study). ConclusionResults suggest that OCA with or without meniscal allograft transplantation in the knee using high-viability grafts, advanced graft cutting and implantation techniques, and procedure-specific rehabilitation protocols can result in consistently successful outcomes in a high percentage (92%) of selected patients. Most patients (95%) can expect to regain, or improve, to “full” functional range of motion (130°) at 1 year after surgery such that highly functional activities can be performed.Level of Evidence: Cohort study; Level III.

Return-to-Sport Review for Current Cartilage Treatments.

The return to play outcome is an important measure for orthopaedic sports medicine treatments. This variable is especially important when discussing cartilage treatments because there are many different cartilage options available to athletes with articular injuries and this population is particularly interested in the ability to return to activities. Although many outcome variables are considered in any surgical procedure, the return-to-sport variable is focused on an active population and can be tailored to that patient's sport-specific goals. In this article, we will review some of the most recent and up-to-date articles describing return-to-sport outcomes for various knee cartilage treatments. This article will focus on the most common current knee cartilage treatments including microfracture, autologous chondrocyte implantation, osteochondral autograft transplant, and osteochondral allograft transplantation.

Next-Generation Marrow Stimulation Technology for Cartilage Repair: Basic Science to Clinical Application.

Given the relatively high prevalence of full-thickness articular cartilage lesions, including in patients who are <40 years of age, and an inability to detect some of these lesions until the time of arthroscopy, there is value in performing a single-stage cartilage procedure such as marrow stimulation (MS). While the positive outcomes of first-generation MS (namely microfracture) have been observed to drop off after 24 months in several studies, improvements have been seen when compared with preoperative conditions for lesions that are 2 to 3 cm2 in size, and MS is considered to be a procedure with technical simplicity, fairly short surgical times, and relatively low morbidity. A recent study showed that autologous chondrocyte implantation (ACI) and osteochondral allograft (OCA) transplantation remain viable treatment options for chondral defects of the knee in the setting of failed MS. Basic science principles that have been elucidated in recent years include (1) the creation of vertical walls during defect preparation, (2) an increased depth of subchondral penetration, (3) a smaller awl diameter, and (4) an increased number of subchondral perforations, which are all thought to help resolve issues of access to the mesenchymal stromal cells (MSCs) and the subchondral bone structure/overgrowth issues. Pioneering and evolving basic science and clinical studies have led to next-generation clinical applications, such as a hyaluronic acid-based scaffold (ongoing randomized controlled trial [RCT]), an atelocollagen-based gel (as described in a recently published RCT), a micronized allogeneic cartilage scaffold (as described in a recently completed prospective cohort study), and a biosynthetic hydrogel that is composed of polyethylene glycol (PEG) diacrylate and denatured fibrinogen (as described in an ongoing prospective study). This review summarizes important points for defect preparation and the recent advances in MS techniques and identifies specific scaffolding augmentation strategies (e.g., mesenchymal augmentation and scaffold stimulation [MASS]) that have the capacity to advance cartilage regeneration in light of recent laboratory and clinical studies.

Osteochondral Allograft Transplantation of the Knee in Adolescent Patients and the Effect of Physeal Closure

The primary aim was to compare osteochondral allograft (OCA) transplantation outcomes between adolescent patients aged 16 years or younger and those older than 16 years. A secondary aim was to analyze the association between physeal closure status and outcomes. Consecutive patients aged 18 years or younger who underwent OCA transplantation with a minimum 2-year follow-up were identified from a prospectively collected database. Patients were divided into 2 groups: those aged 16 years or younger (group 1) and those aged 17 to 18 years (group 2). Outcomes included patient-reported outcomes (PROs), complications, reoperations, and cartilage revision surgery. Outcomes were compared between groups, and physeal status was analyzed as a prognostic indicator. A total of 36 patients met the inclusion criteria: 18 in group 1 and 18 in group 2. There were no significant differences between the groups in terms of demographic characteristics, prior surgical procedures, and surgical details, including concomitant procedures. The mean overall follow-up period was 4.6 ± 2.5 years (range, 2-10.3 years), with no significant difference between the groups (P= .21). There were 10 reoperations (28.8%), 4 in group 1 and 6 in group 2 (P= .47). The overall time to reoperation was 2.8 years and did not significantly differ between groups (P= .75). The failure rate was 5.6%, with 1 patient in each group undergoing either graft debridement or revision OCA transplantation. All PROs were significantly improved postoperatively (P < .05), except for the Western Ontario and McMaster Universities Arthritis Index stiffness score (P= .28) and the Short Form 12 mental score (P= .19). There were no significant between-group differences in terms of PROs. Patients with closed physes had a significantly greater increase in most PROs compared with patients with open physes (P < .05). OCA transplantation in adolescents results in significant PRO score improvement and a low failure rate, albeit reoperations are not uncommon. Patients with closed physes show greater PRO score improvement than those with open physes. Level III, retrospective comparative study.

Management of Large Focal Chondral and Osteochondral Defects in the Knee.

Large, focal articular cartilage defects of the knee (> 4 cm2) can be a source of significant morbidity and often require surgical intervention. Patient- and lesion-specific factors must be identified when evaluating a patient with an articular cartilage defect. In the management of large cartilage defects, the two classically utilized cartilage restoration procedures are osteochondral allograft (OCA) transplantation and cell therapy, or autologous chondrocyte implantation (ACI). Alternative techniques that are available or currently in clinical trials include a hyaluronan-based scaffold plus bone marrow aspirate concentrate, a third-generation autologous chondrocyte implant, and an aragonite-based scaffold. In this review, we will focus on OCA and ACI as the mainstay in management of large chondral and osteochondral defects of the knee. We will discuss the techniques and associated clinical outcomes for each, while including a brief mention of alternative treatments. Overall, cartilage restoration techniques have yielded favorable clinical outcomes and can be successfully employed to treat these challenging large focal lesions.

Do Self-Reported Drug Allergies Influence Clinically Significant Outcome Improvement Following Osteochondral Allograft Transplantation? A Nested Cohort Study.

To compare clinical outcomes for patients who underwent osteochondral allograft transplantation (OCA) based on the presence or absence of one or more self-reported drug allergies. Prospective data were collected from 245 consecutive patients after OCA of the knee from one large academic institution. Patient-reported allergies were obtained via chart review. Patient-reported outcome measures, including activities of daily living of the Knee Outcome Survey (KOS-ADL), Marx Activity Scale, International Knee Documentation Committee (IKDC), and visual analogue scale (VAS) pain were all collected. The minimal clinically important difference (MCID) for each outcome was quantified using a distribution-based method. Independent t tests were used to compare patient-reported outcome measures between those with and without self-reported allergies, while chi-square analysis of association was used to compare rates of MCID achievement. Of 245 patients included, 83 (33.9%) reported having at least one drug allergy at the time of OCA. There were no statistically significant differences with regard to patient demographics, including age, body mass index, gender, or sports participation between those with and without a reported allergy. Similarly, there were no significant differences found between baseline preoperative patient-reported outcomes. Overall, both cohorts demonstrated a significant improvement from baseline scores at 2 years postoperatively. There were no differences found between any patient-reported outcome at 2 years postoperatively. The presence of at least one self-reported drug allergy was not a significant risk factor for failing to achieve the MCID in any specific outcome measure. The presence of one or more drug allergy was not associated with worse patient-reported outcomes or lower rates of clinically significant outcome improvement after OCA.

Meniscal polyurethane scaffold plus cartilage repair in post meniscectomy syndrome patients without malalignment improves clinical outcomes at mid-term follow-up

BackgroundThe aim of this study is to report the mid-term follow-up results of a prospective cohort of patients who underwent a polyurethane (PU) meniscal scaffold implantation for post meniscectomy syndrome (PMS), without limb realignment procedures. MethodsProspective study in patients with PU meniscal scaffolds implanted during 2014–2016. Limb realignment procedures excluded. Clinical outcomes were prospectively evaluated pre-operatively and every year post-operatively using patient-reported outcome scores (KOOS, VAS, Lysholm and IKDC). Post-operative radiologic evaluation was done using 3.0 T magnetic resonance imaging (MRI). Meniscal scaffold extrusion, signal intensity, tibio-femoral cartilage degeneration progression and complications were analyzed. ResultsFourteen patients with an average age of 25.8 years (range: 17–47) received a PU scaffold (8 lateral and 6 medial). Associated procedures were done in all patients, with an osteochondral allograft transplantation (OAT) being the most common. Mean follow up was 51.6 (range: 39–66) months. Post-operative mean clinical outcomes scores showed significantly improved results compared to the pre-operative scores. Lysholm scores increased from 62.4 to 80.2 (P = 0.0023), KOOS from 68.9 to 80 (P = 0.0083) and VAS for pain decreased from 5.3 to 3.1 (P = 0.0024). Average post-operative IKDC score was 67.7. There were 8 cases of complete extrusion (>3 mm). The mean extrusion value was 4.0 mm (range: 3–6 mm). Three patients showed signs of a ruptured meniscal scaffold. One patient showed progression of the cartilage degenerative process. ConclusionThe use of a PU scaffold, associated with other surgical procedures in the knee, especially chondral repair, had a significant improvement in clinical outcomes compared to the baseline status, at an average of 51.6 months follow-up in patients suffering from PMS. Although imaging results show a high proportion of implant extrusion, this does not appear to imply a worsening in clinical outcomes in the short term. Level of evidenceIV. Case series.

Surgical Hip Dislocation and Fresh Osteochondral Allograft Transplantation for Femoroacetabular Impingement and Concomitant Chondral Lesion

Chondral lesions of the hip in young patients are frequently associated with additional articular pathology. Parafoveal osteochondral lesions have been reported to be a manifestation of cam lesions in the setting of femoroacetabular impingement (FAI). Although arthroscopic surgery is useful to treat intra- and extra-articular pathology, large lesions located in areas that are difficult to access represent a limitation of the technique. Open surgical dislocation and osteochondral allograft transplantation (OCA) allow treatment of larger surface areas and underlying morphologic abnormalities such as cam lesions. We present our technique for open surgical dislocation of the hip through a stepped trochanteric osteotomy, osteochondral transplantation of fresh-stored femoral head allograft, and osteoplasty of the head/neck junction.

Local curvature mismatch may worsen the midterm functional outcomes of osteochondral allograft transplantation.

This study aimed to determine the magnitude of local curvature matching in the sagittal plane between an implanted graft and the condylar region receiving the graft and to analyze its effect on clinical outcomes in patients undergoing osteochondral allograft transplantation (OCA). Patients who underwent knee OCA between 2016 and 2019 without circumferential step-off and were matched with a donor in accordance with the conventional matching process were included. The magnitude of donor-host local curvature matching was measured using postoperative sagittal magnetic resonance imaging data with Syngo (Siemens Medical Solutions, Forchheim, Germany) and GeoGebra (GeoGebra GmbH, Linz, AU) software. In addition to radiological evaluation, ROC analysis was performed to compare the patient-reported outcome measures (PROMs) obtained during the 2-year follow-up period among the patients in the SagA group, who had a graft match in the sagittal plane; SagB group, who had low convexity of the graft in the sagittal plane; and SagC group, who had high convexity of the graft in the sagittal plane in accordance with the determined indices. The study included 27 patients who fulfilled the inclusion criteria, and the mean clinical scores of the SagC group were not statistically significantly higher than those of the other groups at any timepoint during the follow-up. The mean Tegner, IKDC, total KOOS and SF-12 physical and mental health scores of the SagC group were lower than those of the other two groups at various follow-up time points, particularly at month 24 (p < 0.05). There were no significant differences between the SagA and SagB groups in the PROMs at any of the follow-up time points (n.s.). The significant differences observed between the SagC group and the other groups in the mean KOOS scores for function in daily living and function in sport and recreation were also observed between the SagA and SagB groups at the follow-ups (p < 0.05). During OCA, a local curvature mismatch between the donor and the host involving large graft convexity may have a negative impact on midterm clinical outcomes. A preoperative analysis of the convexity relationship between the defect site and the graft region in the hemicondylar allograft to be used may enhance donor-host matching. The local analysis method described in the current study may also facilitate graft supply by ensuring donor-host matching without condyle-side and size matching. III.

Midterm Results of Fresh-Frozen Osteochondral Allografting for Osteochondral Lesions of the Talus.

Osteochondral lesions of the talus (OLT) are relatively common. Following the failure of conservative treatment, many operative options have yielded varied results. In this study, midterm outcomes after fresh-frozen osteochondral allograft transplantation for the treatment of OLT were evaluated. Twenty-five patients (12 women and 13 men) with a mean age 40.4 (range 18-70) years between 2009 and 2014 were enrolled. Of 25 ankles, 3, 13, 4, and 4 were involved with the talus at Raikin zone 3, 4, 6, and 7 as well as one coexisted with zone 4 and 6 lesion. The mean OLT area was 1.82 cm2 (range, 1.1-3.0). The mean follow-up period was 5.5 years (range, 4-9.3). Outcomes evaluation included the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, visual analog scale score, and 12-item Short Form Health Survey (SF-12). AOFAS ankle-hindfoot score increased from 74 preoperatively to 94 at 2 years postoperatively (P < .001) and the SF-12 physical health component scores increased from 32 to 46 points (P < .001). Incorporation was inspected in all patients in the latest follow-up, and graft subsidence and radiolucency were observed in 2 and 7 cases, respectively, whereas graft collapse and revision OLT graft were not observed. Bone sclerosis was found in 6 of 25 patients. With respect to midterm results, fresh, frozen-stored allograft transplantation might be an option in the management of symptomatic OLT. Level IV, retrospective case series.

Osteochondral Allograft Transplant of the Patella Using Femoral Condylar Allografts: Magnetic Resonance Imaging and Clinical Outcomes at Minimum 2-Year Follow-up

Background:Fresh osteochondral allograft transplant (OCA) has good outcomes in the knee. However, donor tissue for patellar OCA is limited. Outcomes after nonorthotopic OCA of the patella using more readily available femoral condylar allograft (FCA) tissue have not been previously reported.Purpose:To assess short-term magnetic resonance imaging (MRI) and minimum 2-year clinical outcomes of nonorthotopic patellar OCA using an FCA donor.Study Design:Case series; Level of evidence, 4.Methods:A prospective institutional cartilage registry was reviewed to identify patients treated with patellar OCA using an FCA donor between August 2009 and June 2016. OCA plugs were obtained from the FCA at its trochlear-condylar junction and implanted into the recipient patellar lesion. Early postoperative MRI scans were graded by a blinded musculoskeletal radiologist using the Osteochondral Allograft MRI Scoring System (OCAMRISS). International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), Knee Outcomes Survey–Activities of Daily Living (KOS-ADL), and pain visual analog scale (VAS) scores were collected preoperatively and at minimum 2 years postoperatively, and outcomes were compared using the paired t test.Results:A total of 25 patients were included for clinical outcome analysis and 20 patients for MRI analysis. MRI scans obtained at a mean of 11.4 months (range, 6-22 months) postoperatively showed a mean total OCAMRISS score of 9.0 (range, 7-11); mean bone, cartilage, and ancillary subscores were 2.6, 3.7, and 2.6, respectively. At the latest follow-up (mean, 46.5 months; range, 24-85 months), postoperative improvements were noted in IKDC (from 45.0 to 66.2; P = .0002), KOS-ADL (from 64.3 to 80.4; P = .0012), and VAS (from 5.1 to 3.4; P = .001) scores, with IKDC and KOS-ADL scores above the corresponding previously reported minimal clinically important difference.Conclusion:In this study, patellar OCA using nonorthotopic FCA led to significant short-term improvements in pain and patient-reported outcomes. The majority of nonorthotopic patellar grafts demonstrated full osseous incorporation and good restoration of the articular surface on MRI at short-term follow-up.

A Systematic Review of Fresh Osteochondral Allograft Transplantation for Osteochondral Lesions of the Talus

Category:AnkleIntroduction/Purpose:The term osteochondral lesion of the talus (OLT) refers to any pathology of the talar articular cartilage and corresponding subchondral bone. In general, OLTs can pose a formidable treatment challenge to the orthopaedic surgeon due to the poor intrinsic ability of cartilage to heal as well as the tenuous vascular supply to the talus. Although many treatment options exist, including microfracture, retrograde drilling, autologous chondrocyte implantation (ACI), and osteochondral autograft transfer system (OATS) these options may be inadequate to treat large cartilage lesions. Osteochondral allografts have demonstrated promise as the primary treatment for OLTs with substantial cartilage and bone involvement. To our knowledge, this is the first systematic review of outcomes after fresh osteochondral allograft transplantation for OLTs.Methods:PudMed, the Cochrane Central Register of Controlled Trials, EMBASE, and Medline were searched using PRISMA guidelines. Studies that evaluated outcomes in adult patients after fresh osteochondral allograft transplantation for chondral defects of the talus were included. Operative results, according to standardized scoring systems, such as the AOFAS Ankle/Hindfoot scale and the Visual Analog Scale were compared across various studies. The methodological quality of the included studies was assessed using the Coleman methodology score.Results:There were a total of 12 eligible studies reporting on 191 patients with OLTs with an average follow-up of 56.8 months (range 6-240). The mean age was 37.5 (range 17-74) years and the overall graft survival rate was 86.6%. The AOFAS Ankle/Hindfoot score was obtained pre- and postoperatively in 6 of the 12 studies and had significant improvements in each (P<0.05). Similarly, the VAS pain score was evaluated in 5 of the 12 studies and showed significant decreases (P<0.05) from pre- to postoperatively with an aggregate mean preoperative VAS score of 7.3 and an aggregate postoperative value of 2.6. The reported short-term complication rate was 0%. The overall failure rate was 13.4% and 21.6% percent of patients had subsequent procedures.Conclusion:The treatment of osteochondral lesions of the talus remains a challenge to orthopaedic surgeons. From this systematic review, one can conclude that osteochondral allograft transplantation for osteochondral lesions of the talus results in predictably favorable outcomes with an impressive graft survival rate and high satisfaction rates at intermediate follow-up.

SF-36 Physical Component Score Is Predictive of Achieving a Clinically Meaningful Improvement after Osteochondral Allograft Transplantation of the Femur.

Osteochondral allograft (OCA) transplantation is an increasingly common treatment for patients with symptomatic focal chondral lesions of the knee. There has been increasing interest in determining predictive factors to maximize patient benefit after this operation. The aim of the present study is to evaluate the predictive association of the physical component (PCS) and mental component (MCS) scores of the Short Form 36 (SF-36) questionnaire for achievement of the minimal clinically important difference (MCID) after OCA transplantation. This retrospective study of a longitudinally maintained institutional registry included 91 patients who had undergone OCA transplantation for symptomatic focal osteochondral lesions of the femoral condyle. Included patients were those with complete preoperative questionnaires for the SF-36 and IKDC and completed postoperative IKDC at 2-year follow-up. Multivariate analysis was performed evaluating predictive association of the preoperative MCS and PCS with achievement of the MCID for the IKDC questionnaire. Logistic multivariate modeling demonstrated a statistically significant association between lower preoperative PCS and achievement of the MCID (P = 0.022). A defect diameter >2 cm was also associated with achievement of MCID (P = 0.049). Preoperative MCS did not demonstrate a significant association (P = 0.09) with achievement of the MCID. For this cohort of 91 patients, the preoperative SF-36 PCS and lesion size were predictive of achievement of the MCID at 2-year follow-up after femoral OCA transplantation. These findings support an important role of baseline physical health scores for predicting which patients will obtain a meaningful clinical benefit from this surgery.

Shorter Storage Time Is Strongly Associated With Improved Graft Survivorship at 5 Years After Osteochondral Allograft Transplantation

Background: Current regulations surrounding the use of osteochondral allografts (OCAs) in the United States require delayed graft release after 14 days to complete infectious disease screening. With a generally accepted expiration time of 28 days in storage, a limited window from 14 to 28 days remains for implantation. Yet, the rates of graft survival and thus optimal time for transplantation within this window remain largely unknown. Hypothesis: OCAs transplanted within 19 to 24 days would have lower failure rates at 5 years than those transplanted at 25 to 27 days. Study Design: Cohort study; Level of evidence, 3. Methods: In this retrospective case series, we analyzed data from patients who underwent OCA transplantation (N = 111) by a single surgeon between February 2014 and December 2016 with at least 2-year follow-up. In total, 56 patients received early transplant grafts (storage time, 19-24 days), and 55 received late transplant grafts (storage time, 25-27 days). Survival analysis with Kaplan-Meier curves was performed using log-rank analysis to compare the groups. Multivariable Cox regression analysis was used to assess the influence of OCA storage duration on graft survival while adjusting for age and defect size. Optimal storage time cutoff associated with graft failure was identified by performing receiver operating characteristic curve analysis and calculating the area under the curve. Results: Patients in the late transplant group had a significantly lower rate of graft survival at 5 years postoperatively (70.4%) as compared with patients in the early transplant group (93.1%; P = .027). When correcting for patient age and defect size, late transplant OCAs demonstrated a 3.4-times greater likelihood of failure versus early transplant OCAs. Receiver operating characteristic analysis suggested that OCA transplantation should ideally occur before 25 days of graft storage. Conclusion: OCA transplantation is a safe and successful treatment option for large osteochondral defects of the knee, with excellent rates of in situ graft survival at 5 years. Prioritizing early transplantation of OCAs to <25 days in storage improves rates of graft survival.

Small Cartilage Defect Management.

Cartilage defects in the knee are common resulting in significant pain and morbidity over time. These defects can arise in isolation or concurrently with other associated injuries to the knee. The treatment of small (< 2-3 cm2) cartilage deficiencies has changed as our basic science knowledge of tissue healing has improved. Advancements have led to the development of new and more effective treatment modalities. It is important to address any associated knee injuries and limb malalignment. Surgical options are considered when nonoperative treatment fails. The specific procedure depends on individual patient characteristics, lesion size, and location. Debridement/chondroplasty, microfracture, marrow stimulation plus techniques, fixation of unstable osteochondral fragments, osteochondral autograft transfer, and osteochondral allograft transplantation, all have roles in the treatment of small cartilage defects.

Unicompartmental bipolar osteochondral and meniscal allograft transplantation is effective for treatment of medial compartment gonarthrosis in a canine model.

Osteochondral allograft (OCA) transplantation can restore large articular defects in the knee. Bipolar OCA transplantations for partial and whole joint resurfacing often have less favorable results than single-surface transplants. This study was designed to use a large animal model to test the hypothesis that unicompartmental bipolar osteochondral and meniscal allograft transplantation (BioJoint) would be as or more effective for treatment of medial compartment osteoarthritis (OA) compared to standard-of-care nonoperative treatment. OA was induced in one knee of each research hound (n = 8) using a meniscal release model and pretreatment assessments were performed. After 3 months, dogs were randomly assigned to either the control group (n = 4, no surgical intervention, daily nonsteroidal antiinflammatory drugs [NSAIDs]) or the BioJoint group (n = 4). Clinical, radiographic, and arthroscopic assessments were performed longitudinally and histopathology was evaluated at the 6-month endpoint. At study endpoint, functional, pain, and total pressure index measures, as well as radiographic and arthroscopic grading of graft appearance and joint health, demonstrated superior outcomes for BioJoints compared to NSAID controls. Furthermore, histologic assessments showed that osteochondral and meniscal transplants maintain integrity and integrated into host tissues. Clinical significance: The results support the safety and efficacy of unicompartmental bipolar osteochondral and meniscal allograft transplantation in a preclinical model with highly functional outcomes without early OA progression.

Fresh Osteochondral Allograft Transplants in the Knee: Bipolar and Beyond.

Knee patients who have sustained chondral and osteochondral lesions suffer from debilitating pain, which can ultimately lead to posttraumatic osteoarthritis and whole-joint disease. Older, nonactive patients are traditionally steered toward total knee arthroplasty (TKA), but younger, active patients are not good candidates for TKA based on implant longevity, complications, morbidity, and risk for revision, such that treatment strategies at restoring missing hyaline cartilage and bone are highly desired for this patient population. Over the past four decades, fresh osteochondral allograft (OCA) transplantation has been developed as a treatment method for large (> 2.5 cm2) focal full-thickness articular cartilage lesions. This article documents our own institutional OCA journey since 2016 through enhanced graft preservation techniques (the Missouri Osteochondral Preservation System, or MOPS), technical improvements in surgical techniques, use of bone marrow aspirate concentrate, bioabsorbable pins and nails, and prescribed and monitored patient-specific rehabilitation protocols. Further follow-up with documentation of long-term outcomes will provide insight for continued optimization for future applications for OCA transplantation, potentially including a broader spectrum of patients appropriate for this treatment. Ongoing translational research is necessary to blaze the trail in further optimizing this treatment option for patients.