Fresh Osteochondral Allograft Versus Autograft: Twelve-Month Results in Isolated Canine Knee Defects.

BACKGROUND: Osteochondral autografts and allografts have been widely used in the treatment of isolated grade 4 articular cartilage lesions of the knee. However, there is a paucity of literature regarding the basic science investigating the direct comparison between fresh osteochondral allografts to autografts. HYPOTHESIS: At 12 months, fresh osteochondral allografts are equal to autografts with respect to function, bony incorporation into host bone, and chondrocyte viability. STUDY DESIGN: Controlled laboratory study. METHODS: Eight adult mongrel dogs underwent bilateral hindlimb osteochondral graft implantation in the knee after creation of an acute Outerbridge grade 4 cartilage defect. One hindlimb of each dog knee received an autograft, and the contralateral knee received an allograft. All dogs were sacrificed at 12 months. Graft analysis included gross examination, radiographs, magnetic resonance imaging (MRI), biomechanical testing, and histology. RESULTS: MRI demonstrated excellent bony incorporation of both autografts and allografts, except for 1 allograft that revealed partial incorporation. Histologic examination of cartilage showed intact hyaline appearance for both autografts and allografts, with fibrocartilage at the host-graft interface of both. Biomechanical testing demonstrated no significant difference between allografts and autografts (P = .76). Furthermore, no significant difference was observed between allografts and the native cartilage with biomechanical testing (P = .84). CONCLUSION: After 12 months from time of implantation, fresh osteochondral allograft tissue and autograft tissue in this study were not statistically different with respect to biomechanical properties, gross morphology, bony incorporation, or overall histologic characteristics. When compared with the previously reported 6-month incorporation rates, there was improved allograft and autograft incorporation at 12 months. CLINICAL RELEVANCE: With no significant differences in gross examination, radiographs, MRI, biomechanical testing, or histology in the canine model, the use of allograft tissue to treat osteochondral defects may eliminate the morbidity associated with autograft harvest.

Interobserver reliability of the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification of meniscal tears.

BACKGROUND: Consistency of arthroscopic evaluation and documentation in meniscal tears between investigators is essential to the validity of multicenter studies. A group of experts developed a classification of meniscal tears that may be used internationally. HYPOTHESIS: The International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification of meniscal tears provides sufficient interobserver reliability for pooling of data from international clinical trials designed to evaluate the outcomes of treatment for meniscal tears. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 1. METHODS: A pilot study was performed by having 8 members of the committee grade 10 arthroscopic videos for classification of tear depth, rim width, location, tear pattern, and quality of the tissue. The results of the pilot study were used to change the instruction sheet and evaluation form. International interobserver reliability was determined by having 8 orthopaedic surgeons who practice in different countries evaluate 37 arthroscopic videos selected to represent different meniscal tear characteristics. The Spearman ρ correlation coefficient was used to compare the area of the meniscus excised, as drawn on the diagram, with the numeric percentage of meniscus excised. RESULTS: There was an 87% agreement for anterior-posterior location of the tear (κ = .65); 79% agreement for tear pattern (κ = .72); 88% agreement for tear depth (κ = .52); 68% agreement for anterior, middle, and posterior location of the tear (κ = .46); and 72% agreement for tissue quality (κ = .47). There was 54% agreement for the rim width (κ = .25) and 67% agreement if the tear was central to the popliteal hiatus (κ = .36). Based on the Landis and Koch criteria for κ coefficients, there was substantial agreement for anterior-posterior location of the tear and tear pattern; moderate agreement for tear depth, anterior, middle, and posterior location of the tear, and tissue quality; and fair agreement for rim width and if the tear was central to the popliteal tear. Interobserver reliability based on the intraclass correlation coefficient (ICC) was good for tear length (ICC = .83) and moderate for percentage of meniscus that was excised (ICC = .65). The mean ρ for all raters was .92 (95% confidence interval [CI], .89-.94) comparing the values for percentage of meniscus excised with the area on the diagrams. CONCLUSION: The ISAKOS classification of meniscal tears provides sufficient interobserver reliability for pooling of data from international clinical trials designed to evaluate the outcomes of treatment for meniscal tears.

Articular cartilage thickness of the humeral head: an anatomic study.

This study determined the thickness of normal humeral head articular cartilage by anatomic cross section using computer-aided image analysis software. Sixteen adult cadaveric humeral heads were analyzed. Our findings reveal that the thickness of humeral articular cartilage is substantially thinner than articular cartilage found in the knee. The cartilage is thickest in the central portion of the head and becomes progressively thinner towards the periphery. Surgical techniques used to treat pathology in the glenohumeral joint, specifically thermal energy or mechanical debridement, may have deleterious effects on the relatively thin humeral articular cartilage.

The accessory posteromedial portal revisited: utility for arthroscopic rotator cuff repair.

Arthroscopic rotator cuff repair is a technically challenging procedure. Accessory arthroscopic portals have been described that allow for optimal suture anchor placement, suture management, and knot tying. We describe here the usefulness of an accessory posteromedial portal that facilitates direct suture retrieval through the posterior aspect of a rotator cuff tear. This portal is created approximately 4 to 5 cm medial to the posterolateral corner of the acromion and 2 cm inferior to the scapular spine. The accessory posteromedial portal is especially useful when a retracted tear of the infraspinatus or teres minor is encountered. Because these tendons retract in a posterior and medial direction, the accessory posteromedial portal places the tendon-penetrating device in an ideal position for suture passage through the posterior portion of the rotator cuff tear. This portal also allows placement of margin convergence sutures for large U-shaped or L-shaped tears by permitting a direct "hand-off" of the suture to or from a second penetrating device that is placed through a standard anterior portal. If multiple suture anchors are required (as in the case of large or massive cuff tears, or when double-row fixation is employed), sutures can be pulled out through the accessory posteromedial portal to facilitate suture management.

Comparison of fresh osteochondral autografts and allografts: a canine model.

BACKGROUND: Osteochondral autografts and allografts have been widely used in the treatment of isolated grade IV articular cartilage lesions of the knee. However, the authors are not aware of any study that has prospectively compared fresh osteochondral autografts to fresh allografts with regard to imaging, biomechanical testing, and histology. HYPOTHESIS: The imaging, biomechanical properties, and histologic appearance of fresh osteochondral autograft and fresh allograft are similar with respect to bony incorporation into host bone, articular cartilage composition, and biomechanical properties. STUDY DESIGN: Controlled laboratory study. METHODS: Eighteen adult dogs underwent bilateral knee osteochondral graft implantation after creation of an Outerbridge grade IV cartilage defect. One knee received an autograft, and the contralateral knee received a fresh allograft. Nine dogs were sacrificed at 3 months, and 9 dogs were sacrificed at 6 months. Graft analysis included gross examination, radiographs, magnetic resonance imaging, biomechanical testing, and histology. RESULTS: Magnetic resonance imaging demonstrated excellent bony incorporation of both autografts and allografts. Biomechanical testing demonstrated no significant difference between autografts versus allografts versus control at 3 or 6 months (P = .36-.91). A post hoc calculation showed 80% power to detect a 30% difference between allograft and control. Histologic examination showed normal cartilage structure for both autografts and allografts. CONCLUSION: Fresh osteochondral autograft and fresh allograft tissues are not statistically different with respect to bony incorporation, articular cartilage composition, or biomechanical properties up to 6 months after implantation. CLINICAL RELEVANCE: The use of fresh allograft tissue to treat osteochondral defects eliminates morbidity associated with harvesting autograft tissue without compromising the results of the surgical procedure.