Osteochondral Graft Transplantation Research Articles

Treatment of Shoulder Cartilage Defects in Athletes.

Articular cartilage defects in the glenohumeral joint may be found in laborers, the elderly, and young athletes, among others. Various factors can contribute to cartilage damage, including prior surgery, trauma, avascular necrosis, inflammatory arthritis, joint instability, and osteoarthritis. There is a wide variety of treatment options, from conservative treatment, injections, and surgical options, including arthroscopic debridement, microfracture, osteochondral autograft transfer, osteochondral graft transplantation, autologous chondrocyte implantation, and the newly emerging techniques such as biologic augmentation. There is a challenge to determine the optimal treatment options, especially for young athletes, due to limited outcomes in the literature. However, there are many options which are viable to address osteochondral defects of the glenohumeral joint.

Functional outcome after arthroscopic mosaicplasty for localized osteochondral defects in the knee

Background: Articular cartilage is complex tissue that is able to withstand tremendous amount of force over many cycle but does not have the ability to heal even after minor injury. Treatment recommendation for articular cartilage injury and arthritis includes non-operative and operative management. Mosaicplasty is a reconstructive osteochondral grafting procedure for the treatment of articular defects of the knee. Mosaicplasty entails transplantation of small cylindrical osteochondral grafts from the non-weight bearing area of the femoral condyles and transplanting them in a mosaic like fashion into a prepared defect site on the weight-bearing surfaces of the same knee. Methods: The present study was carried out in 30 patients in our hospital prospectively to determine the functional outcome results after arthroscopic mosaicplasty for localized osteochondral defects in the knee. We conducted a prospective study on 30 patients of osteochondral defect of knee. Patients were presented with pain and recurrent swelling in the knee after sustaining twisting injury in the knee. Diagnostic arthroscopy was done and the osteochondral defects is localized and treated with mosaicplasty. The graft is harvested arthoscopically from the non-weight bearing part of the femoral condyles using a harvester. Follow up of these patients is done according to Tenger Lysholm knee scoring scale at 03 months, 06 months after surgery. Results: In our study 93.33% patients showed good to excellent results and 7% patients had fair and poor results. Conclusions: Advantage of arthroscopic mosaicplasty includes implantation of hyaline cartilage without the need for any suture or adhesive, need for smaller incision minimally invasive and very less complications. Associated injuries like ACL/PCL or meniscal tear can be addressed in the same procedure. To conclude arthroscopic mosaicplasty is excellent procedure to address the focal articular cartilage injuries of knee.

Treatment of osteochondritis dissecans

Osteochondritis dissecans (OD) is arare condition with an incidence of 30/100,000. It especially affects male patients aged 10-20years old. During the staged progression the osteochondral fragments can detach from their base. These can damage the adjacent articular cartilage, which can lead to premature osteoarthritis. Most commonly affected are the knee, ankle and elbow joints. The exact pathogenesis of OD has so far not been clearly confirmed. Several risk factors that can lead to the development of OD are discussed. These include repeated microtrauma and vascularization disorders that can lead to ischemia of the subchondral bone and to aseparation of the fragments close to the joint and therefore to the development of free joint bodies. For an adequate clarification patients should undergo athorough radiological evaluation including X‑ray imaging followed by magnetic resonance imaging (MRI) to assess the integrity of the cartilage-bone formation with determination of the OD stage. The assessment is based on criteria of the International Cartilage Repair Society (ICRS). The instability of the cartilage-bone fragment increases with higher stages. StagesI andII with stable cartilage-bone interconnection can be treated conservatively. For stagesIII andIV, i.e., instability of the OD fragment or the presence of free fragments, surgical treatment should be performed. Primarily, refixation of afree joint body should be carried out depending on the size and vitality of the fragment. In cases of unsuccessful conservative treatment or fixation, adebridement, if necessary in combination with a bone marrow stimulating procedure, can be employed corresponding to the size of the defect. For larger cartilage defects, an osteochondral graft transplantation should be considered. Overall, OD lesions in stagesI andII show agood healing tendency under conservative treatment. In cases of incipient unstable OD, refixation can also lead to good clinical and radiological results.

The regenerative treatment of costal osteochondral graft implantation for partial growth arrest using a rabbit model

PurposeTo investigate the feasibility of cylindrical costal osteochondral graft transplantation as a novel regenerative treatment in growth arrest. MethodsThe medial portion of the proximal tibial growth plate of 6-week-old male New Zealand White rabbits was resected to establish an experimental model of partial growth plate injury. The rabbits were divided into four groups: no-treatment, bone wax transplantation, costal chondral graft, and costal osteochondral graft groups. Radiographic and micro-computed tomography scan results were analyzed to evaluate angular deformity of the tibia and bony bridge formation at the injury site. In addition, repair of the injured growth plate cartilage was assessed histologically at 4, 8, and 12 weeks postoperatively. ResultsRadiographic examination revealed that bone wax transplantation continuously decreased the medial proximal tibial angle (MPTA) while the costal chondral graft implantation reduced the decrease of MPTA at 12 weeks postoperatively. The costal osteochondral graft implantation recovered the MPTA, close to the normal. Histologically, the costal osteochondral grafts retained the MPTA in the injured site compared to costal chondral grafts. Additionally, hypertrophic chondrocytes were observed at the graft site in the costal osteochondral graft group at 12 weeks, suggesting that endochondral ossification may occur at the graft site similar to normal ossification. The fluorescence in situ hybridization analysis of osteochondral grafts transplanted from male to female rabbits indicated that they were replaced by cells of host origin. ConclusionThe costal osteochondral graft can achieve regeneration without bony bridge formation in partial growth plate injury.

Characterisation of subchondral bone repair following transplantation of bioreactor-manufactured autologous osteochondral graft in a sheep model.

To date, no single approach to the treatment of osteochondral defects has resulted in satisfactory long-term outcomes, especially in a young and active human population. Emerging innovative tissue engineering strategies, including the use of composite scaffolds, novel cell sources and bioreactors, have shown promising results. However, these techniques need to be validated in translational animal models before they can be implemented in clinical practice. The aim of the present study was to analyse morphological and microarchitectural parameters during subchondral bone repair following transplantation of bioreactor-manufactured autologous osteochondral grafts in a sheep model. Animals were divided into 4 treatment groups: nasal chondrocyte (NC) autologous osteochondral grafts, articular chondrocyte (AC) autologous osteochondral grafts, cell-free scaffolds (CFS) and empty defects (EDs). After 6 weeks, 3 months and 12 months, bone remodelling was assessed by histology and micro-computed tomography (µCT). Although gradual remodelling and subchondral bone repair were seen in all groups across the time points, the best results were observed in the NC group. This was evidenced by the extent of new tissue formation and its best integration into the surrounding tissue in the NC group at all time points. This also suggested that nasal septum chondrocyte-seeded grafts adapted well to the biomechanical conditions of the loaded joint surface.

Midterm Outcomes of Autologous Osteochondral Graft Transplantation Only in the Femoral Condyle without Treating the Tibial Plateau with Subchondral Bone Exposed.

This study aimed to examine the midterm clinical outcomes of autologous osteochondral grafts (AOG) that were performed in the femoral condyle without treating the tibial plateau with subchondral bone exposed, and to compare these outcomes with those of AOG used in patients with osteoarthritis (lateral type or medial type) or osteonecrosis. The study included 6 men and 16 women and 11 right knees and 11 left knees. The mean operative age was 56.0 years (range, 21-76 years), and the mean follow-up period was 98.4 months (range, 60-164 months). Six patients had lateral type osteoarthritis (OAL), 7 had medial type osteoarthritis (OAM), and 9 had osteonecrosis (ON). The patients' knee symptoms as their clinical outcome were evaluated using the knee scoring system of the Japanese Orthopedic Association (JOA), and the International Knee Documentation Committee (IKDC) subjective score. The postoperative clinical outcomes of the OAL and ON group were significantly better than their preoperative clinical scores and remained the same until the final follow-up. However, the clinical outcomes of OAM improved 2 years after AOG, but eventually decreased thereafter. The number of worse cases in the OAM group was significantly larger than those in the OAL and ON groups. In these procedures, the postoperative clinical outcomes of the OAL and ON groups were significantly better than their preoperative clinical scores and were maintained for about 8 years. However, the clinical outcomes of OAM improved until 2 years after AOG, but eventually decreased thereafter.

Comparison of autologous osteoperiosteal cylinder and osteochondral graft transplantation in the treatment of large cystic osteochondral lesions of the talus (OLTs): a protocol for a non-inferiority randomised controlled trial

IntroductionLarge cystic osteochondral lesions of the talus (OLTs) have been shown to have inferior clinical outcomes after reparative techniques such as bone marrow stimulation. Autologous osteochondral transplantation has been viewed...

Can the MOCART Scoring System Correlate with Patient Reported Foot and Ankle Outcome Scores After Ankle Cartilage Repair Procedures?

Category:Ankle, Arthroscopy, SportsIntroduction/Purpose:The magnetic resonance observation of cartilage repair tissue (MOCART) scoring system was developed and modified to allow for assessment of articular cartilage repair tissue in the foot and ankle. The purpose of this study was to evaluate the intra- and inter-rater reliability of the MOCART score following a variety of surgical procedures to repair chondral injuries within the ankle joint as well as to correlate these scores to clinically relevant functional outcomes scores. By correlating functional outcome scores with each variable evaluated by the MOCART scoring system as well as the presence of edema and cysts postoperatively, we aimed to identify the radiographic parameters most closely associated with clinical outcomes.Methods:Patients treated for a chondral injury after August 2006 by a fellowship-trained foot and ankle surgeon at our institution were included if their postoperative MRI and Foot and Ankle Outcome Score (FAOS) were completed within 5 months of one another. Surgical interventions used to stimulate reparative cartilage formation included osteochondral graft transplantation, debridement, microfracture, microfracture augmented by bone marrow aspirate concentrate (BMAC), juvenile particulate cartilage implantation, or another adjunctive therapy like micronized allogenic cartilage extracellular matrix. Two radiologists (R1-R2) independently reviewed and scored each MRI using the MOCART system. A total MOCART score ranging between 0 and 100 was calculated for each patient. In addition, the presence or absence of postoperative cysts and edema was documented. Inter- and intra- rater reliability were calculated using Intraclass Correlation Coefficients (ICC), and MOCART scores were correlated with FAOS to test for relative functional and clinical relevance. Correlations were calculated as Pearson Correlation Coefficients.Results:Forty-six patients (average age 35 +/- 13.49) under the care of nine different surgeons met inclusion criteria. Average follow-up was 18 months. For overall MOCART score, intra-rater ICC = 0.87 (p<0.01) for R1 and ICC = 0.78 (p<0.01) for R2. Inter-rater reliability ICC = 0.55 – 0.69 for total MOCART score (p<0.01). Overall MOCART score negatively correlated with pre-to-postoperative differences in FAOS subcategories. Correlation coefficients ranged from -0.09 to -0.48 for these variables. This correlation was significant (p<0.01) for the difference in the FAOS Pain and Activities of Daily Living subcategories. In addition, change in FAOS Pain subcategory (r = 0.42; p=0.01) and lesion size (r=0.45; p<0.01) had a moderate but significant correlation with the presence of postoperative cysts (r = 0.42; p=0.01).Conclusion:Intra-rater reliability for an overall MOCART score was relatively strong for each rater while the correlation between raters ranged from strong to moderate. As such, an overall MOCART score appears to be a somewhat reproducible measure. Weak to moderate negative correlational coefficients between the overall MOCART score and postoperative FAOS scores and changes in FAOS scores indicated the MOCART score may be limited in its ability to predict clinical outcomes. Finally, presence or absence of a postoperative cyst may be a useful category that significantly helps predict changes in FAOS pain as well as the size of the lesion preoperatively.

Autologous Osteochondral Graft for Early Posttraumatic Arthritis of Tibiotalar Joints After Comminuted Pilon Fractures in Young Patients

Posttraumatic arthritis of tibiotalar joints after AO/OTA type C3 pilon fractures, especially in young patients with a significant osteochondral defect in the tibial plafond joint surface, is a challenging situation. We report a joint-preserving technique using autologous osteochondral graft in combination with ankle distraction and supramalleolar osteotomy (SMOT), if necessary, to improve its outcome. Seventeen patients with an average age of 32.1 years with Takakura grade 1 to 3A posttraumatic arthritis of the tibiotalar joint after AO/OTA type C3 pilon fractures received osteochondral autograft transplantation, ankle distraction, and SMOT, when supramalleolar malalignment was present, between February 2010 and November 2015. The visual analog scale (VAS), Short-Form 36 (SF-36) score, American Orthopaedic Foot & Ankle Society (AOFAS) score, and ankle range of motion were used for outcome analysis. Radiographic assessment of any SMOT and the apparent joint space was performed. Fourteen patients were followed for an average of 18 months. The VAS, SF-36, and AOFAS scores as well as the ankle range of motion all improved significantly at the last follow-up after the surgery (P < .01). No deep surgical site infection, donor site complication, nonunion, osteochondral block loosening, or resorption was noted. No secondary arthrodesis was needed at the end of follow-up. Autologous osteochondral graft transplantation in combination with ankle distraction and SMOT was a promising joint-preserving technique for early posttraumatic arthritis of tibiotalar joint after severe pilon fractures in young patients. Level IV, case series.

Do Nonsteroidal Anti-Inflammatory Drugs Have a Deleterious Effect on Cartilage Repair? A Systematic Review.

The purpose of this study was to systematically review the available evidence regarding any plausible deleterious effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on chondrocytes, chondrocyte differentiation, and allograft or autograft incorporation after cartilage repair procedures. Three databases (PubMed, Science Direct, and Cochrane Library) were screened for eligible studies: investigating the effects of NSAIDs on chondrocytes, chondrogenic differentiation, or allograft/autograft incorporation. This evaluation included studies of any level of evidence, written in English, reporting clinical or preclinical results, published in peer review journals and dealing with our topic. All articles evaluating the effects of NSAIDs on either osteoarthritic (OA) chondrocyte samples or OA chondrocyte models were excluded. Moreover, articles about bone healing in which allograft or autograft incorporation was not investigated were also excluded. Methodologic quality assessment was performed for in vivo animal studies according to ARRIVE guidelines, and risk of bias of each included study was identified using the ROBINS-I tool. Eighteen studies were included in the review: 4 in vitro studies, 13 animal studies, and 1 human study. According to these studies NSAIDs have no detrimental effect on healthy mature chondrocytes; however, these drugs influence chondrocyte differentiation and graft incorporation and therefore may interfere with chondrogenesis and incorporation after transplantation of chondrocytes or osteochondral grafts. The use of NSAIDs, systemic or local, after cartilage repair procedures should be avoided unless a substantial clinical benefit would otherwise be withheld from the patient. More human studies are needed to analyze the effect of NSAIDs on cartilage repair.

Operative treatment of cartilage lesions

Cartilage damage is often associated with pain, reduced quality of life and decreased physical performance. In addition, even small cartilage lesions can lead to osteoarthritis. Since young active people are particularly affected, the correct treatment of cartilage damage plays an important role. Operative treatment includes bone marrow-stimulating procedures with or without a matrix, cell-based procedures and osteochondral graft transplantation. The choice of the best procedure depends on the localization, the size and the extent of the cartilage damage. In addition, especially in the treatment of cartilage damage to the lower limbs, the leg axis and loading relationships should be taken into account and possibly treated as well as additional joint instabilities. The following article gives an overview of the available surgical treatment possibilities as well as the correct indications and implementation. It also gives abrief projection of possible further treatment options associated with stem cells.

Nondestructive Assessment of Articular Cartilage Electromechanical Properties after Osteochondral Autologous and Allogeneic Transplantation in a Goat Model.

To determine the applicability of a minimally invasive diagnostic device to evaluate the quality of articular cartilage following autologous (OAT) and allogeneic (OCA) osteochondral graft transplantation in goat model. OAT grafts were harvested from lateral femoral condyles (LFCs) and transplanted into osteochondral defects created in medial femoral condyles (MFCs) of contralateral knees. OCA grafts were transplanted into MFC condyles after in vitro storage. Autologous platelet-rich plasma (PRP) was administered intraarticularly after the surgery and at 1 and 2 months postoperatively. OAT and OCA grafts were evaluated macroscopically (Oswestry arthroscopy score [OAS]), electromechanically (quantitative parameter, QP), and histologically (O'Driscoll score, safranin O staining intensity) at 3 and 6 months after transplantation. Results were compared with preoperative graft evaluation. Transplanted cartilage deteriorated within 6 months in all groups. Cartilage quality was better retained in OAT group compared with a decline in OCA group. QP and OAS scores were comparable in OAT and OCA groups at 3 months, but superior in OAT group at 6 months, according to all the methods applied. PRP injections significantly improved QP and OAS score at 6 months compared with 3 months in OAT group. QP moderately correlated with OAS, O'Driscoll score, and safranin O staining intensity. Grafts did not retain preoperative quality parameters at 6 months follow-up; however, OAT were superior to OCA grafts. PRP may have a beneficial effect on macroscopic and electromechanical properties of cartilage; however, histological improvement is yet to be proved. Electromechanical diagnostic device enables reliable assessment of transplanted cartilage.

Changes in dissipated energy and contact pressure after osteochondral graft transplantation

Osteochondral autologous transplantation is frequently used to repair small cartilage defects. Incongruence between the osteochondral graft surface and the adjacent cartilage leads to changed friction and contact pressure. The present study wanted to analyze the differences between intact and surgically treated cartilage surface in respect to contact pressure and frictional characteristic (dissipated energy). Six ovine carpometacarpal joints were used in the present study. Dissipated energy during instrumentally controlled joint movement as well as static contact pressure were measured in different cartilage states (intact, defect, deep-, flush-, high-implanted osteochondral graft and cartilage failure simulation on a high-implanted graft). The best contact area restoration was observed after the flush implantation. However, the dissipated energy measurements did not reveal an advantage of the flush implantation compared to the defect and deep-implanted graft states. The high-implanted graft was associated with a significant increase of the mean contact pressure and decrease of the contact area but the dissipated energy was on the level of intact cartilage in contrast to other treatments where the dissipated energy was significantly higher as in the intact state. However the cartilage failure simulation on the high-implanted graft showed the highest increase of the dissipated energy.

Paper 42: Autologous Osteochondral Grafts in the Treatment of Focal Chondral Defects of the Femoral Head: An Experimental Study in Rabbits

To investigate and compare macroscopically and histologically the reconstructed articular surface of a focal defect of the right femoral head treated with subchondral drilling or autologous osteochondral transplantation in rabbits A 2,5 mm diameter and 3 mm depth iatrogenic osteochondral defect in the anterolateral weight bearing area of the right femoral head was created in 12 rabbits. Autologous osteochondral transplantation was performed in a group of 6 rabbits. Donor site was the lateral condyle of the ipsilateral knee joint. The other group of 6 rabbits was treated with subchondral drilling. Both groups were sacrificed and evaluated histologically under the classification system of the ICRS after 6 weeks. For statistical analysis we used the Mann – Wittney test According to the ICRS, score statistical significance favoring the osteochondral transplantation was found in all variables between the 2 groups: articular surface (p=0,049), matrix (p=0,003), cell distribution (p< 0,0005), subchondral bone (p=0,010), cartilage mineralization (p=0,0) except cell population viability. In comparison to subchondral drilling, autologous osteochondral transplantation offered mature fully constructed tissue providing better results. Both methods provided viable cells. All grafts had successful incorporation of the osseous part. No necrosis of the femoral head was noticed. Reconstruction of the articular surface of the femoral head through autologous osteochondral graft transplantation after focal osteochondral defect in rabbits gives superior macroscopical and histological results in comparison to subchondral drilling

Arthroscopic Mosaicplasty for Osteochondral Lesions of the Knee: Computer-Assisted Navigation Versus Freehand Technique

The purpose of this study was to compare a freehand arthroscopic approach versus mosaicplasty for treatment of osteochondral lesions of the knee with a navigated arthroscopic technique. Four whole cadaveric lower limbs were used. A conventional navigation system was used in combination with an autologous osteochondral graft transplantation system (Osteochondral Autograft Transfer System [OATS]; Arthrex, Naples, FL). The congruity of the articular surface was measured with the navigation probe to detect any difference between the surface created by the grafts and the surface of the femoral condyle surrounding them. The angle relates to a line perpendicular to the articular surface. This line is made by the cutting instrument for graft harvesting and insertion and the articular surface. The mean angle of graft harvest was 3.4° (range, 0° to 10°) in the navigated group versus 14.8° (range, 6° to 26°) in the freehand group (P < .0003). The mean angle for recipient-site coring was 1.5° (range, 0° to 5°) in the navigated group versus 12.6° (range, 4° to 17°) in the freehand group (P < .0003). The mean angle of graft placement was 2° (range, 1° to 5°) in the navigated group versus 10.8° (range, 5° to 15°) in the freehand group (P = .0002). The mean protrusion height of the plug was 0.23 mm (range, 0.1 to 0.5 mm; SD, 0.16) in the navigated group versus 0.34 mm (range, 0.0 to 0.7 mm; SD, 0.25) in the freehand group (P = .336). Computer-assisted arthroscopic mosaicplasty for treatment of osteochondral lesions in the cadaveric model presented in this study allows permanent visualization of the angle of recipient-site preparation, the depth of the donor plug and the recipient plug, and the angle of insertion of the graft at the recipient site. This study shows evidence of potentially greater precision and reproducibility of navigated arthroscopic mosaicplasty when compared with an arthroscopic freehand technique in a cadaveric model. However, true clinical outcome benefit will only be elucidated upon performance of appropriate clinical studies.

Autogenous osteochondral graft transplantation for steroid-induced osteonecrosis of the femoral condyle: A report of three young patients

Steroid-induced osteonecrosis of the femoral condyle is a relatively uncommon condition and is often difficult to select appropriate treatment especially in young patients. Three young men (aged 25, 18, and 24) presented with severe pain and dysfunction of the knee diagnosed as steroid-induced osteonecrosis of the femoral condyle by magnetic resonance imaging (MRIs). Full-thickness cartilage defects sized 20 × 10, 15 × 10, and 30 × 20 mm respectively were classified as International Cartilage Repair Society Grade IV lesions and treated with osteochondral autograft transplantation. They were treated successfully with osteochondral autograft transplantation certificated by post-operative MRI and second look arthroscopy.

An Unusual Cause of a Cystic Lesion with an Osteochondral Defect in the Talus

An intraosseous lipoma is a rare benign bone lesion that proliferates from mature lipocytes. It occurs most frequently in the lower limb, particularly in the calcaneus. The talus is an unusual location for this rare lesion. A review of the literature produced only two reports with talar intraosseous lipomas under the name of intraosseous lipomatosis, which described multiple lipomas in different areas. We describe a 38-year-old male patient who had an isolated intraosseous lipoma with an osteochondral defect in the talus and was treated with autologous osteochondral graft transplantation by medial malleolar osteotomy. He could walk with full weightbearing without any assistance at the end of 12 months. Intraosseous lipoma localized in the talus may be confused radiologically with other bone lesions, especially with unicameral bone cyst, if it is associated with an osteochondral defect. Autologous osteochondral graft transplantation is a successful treatment method for talar intraosseous lipoma.

Strategies for Articular Cartilage Lesion Repair and Functional Restoration

Injury of articular cartilage due to trauma or pathological conditions is the major cause of disability worldwide, especially in North America. The increasing number of patients suffering from joint-related conditions leads to a concomitant increase in the economic burden. In this review article, we focus on strategies to repair and replace knee joint cartilage, since knee-associated disabilities are more prevalent than any other joint. Because of inadequacies associated with widely used approaches, the orthopedic community has an increasing tendency to develop biological strategies, which include transplantation of autologous (i.e., mosaicplasty) or allogeneic osteochondral grafts, autologous chondrocytes (autologous chondrocyte transplantation), or tissue-engineered cartilage substitutes. Tissue-engineered cartilage constructs represent a highly promising treatment option for knee injury as they mimic the biomechanical environment of the native cartilage and have superior integration capabilities. Currently, a wide range of tissue-engineering-based strategies are established and investigated clinically as an alternative to the routinely used techniques (i.e., knee replacement and autologous chondrocyte transplantation). Tissue-engineering-based strategies include implantation of autologous chondrocytes in combination with collagen I, collagen I/III (matrix-induced autologous chondrocyte implantation), HYAFF 11 (Hyalograft C), and fibrin glue (Tissucol) or implantation of minced cartilage in combination with copolymers of polyglycolic acid along with polycaprolactone (cartilage autograft implantation system), and fibrin glue (DeNovo NT graft). Tissue-engineered cartilage replacements show better clinical outcomes in the short term, and with advances that have been made in orthopedics they can be introduced arthroscopically in a minimally invasive fashion. Thus, the future is bright for this innovative approach to restore function.

Autogenous Bone-cartilage Transplantation

Autogenous osteochondral plug transplantation has been carried out worldwide to repair chondral/osteochondral defects of the weight-bearing joint surface. The researchers report arthroscopic multiple osteochondral graft transplantation for chondral lesions in ACL- deficient knees. With advances of o

Osteochondral Tissue Cell Viability Is Affected by Total Impulse during Impaction Grafting.

Objective:Osteochondral graft transplantation has garnered significant attention because of its ability to replace the lesion with true hyaline cartilage. However, surgical impaction of the graft to anchor it into the defect site can be traumatic and lead to cell death and cartilage degeneration. This study aimed to test the hypothesis that increasing impulse magnitude during impaction of osteochondral plugs has a direct effect on loss of cell viability.Design:In this controlled laboratory study, the impaction force was kept constant while the impulse was varied. Ninety-six osteochondral plugs were extracted from the trochlea of bovine stifle joints and were randomly assigned into 3 experimental and 1 (nonimpacted) control group. The transferred impulse of the experimental groups reflected the median and the lower and upper quartiles of preceding clinical measurements. Data were obtained at day 0, day 4, and day 8; at each point, cell viability was assessed using the Live/Dead staining kit and histological assessments were performed to visualize matrix structural changes.Results:After impaction, cartilage samples stayed intact and did not show any histological signs of matrix disruption. As expected, higher impulse magnitudes introduced more cell death; however, this relationship was lost at day 8 after impaction.Conclusion:Impulse magnitude has a direct effect on cell viability of the graft. Because impulse magnitude is mostly governed by the press-fit characteristics of the recipient site, this study aids in the definition of optimal insertion conditions for osteochondral grafts.