Biologically Regulated Marrow Stimulation by Blocking TGF-β1 With Losartan Oral Administration Results in Hyaline-like Cartilage Repair: A Rabbit Osteochondral Defect Model.

Background: Microfracture or bone marrow stimulation (BMS) is often the first choice for clinical treatment of cartilage injuries; however, fibrocartilage, not pure hyaline cartilage, has been reported because of the development of fibrosis in the repair tissue. Transforming growth factor β1 (TGF-β1), which can promote fibrosis, can be inhibited by losartan and potentially be used to reduce fibrocartilage.

Hypothesis: Blocking TGF-β1 would improve cartilage healing in a rabbit knee BMS model via decreasing the amount of fibrocartilage and increasing hyaline-like cartilage formation.

Meniscus suture repair: minimum 10-year outcomes in patients younger than 40 years compared with patients 40 and older.

Background: Few studies have compared outcomes after meniscus suture repair in patients younger than 40 years versus patients 40 years and older.

Purpose: To document failure rates and long-term outcomes after meniscus suture repair by a single surgeon, using the inside-out technique, at a minimum 10-year follow-up in patients younger than 40 years versus those 40 years and older.

Study Design: Cohort study; Level of evidence, 3.

Resorbable collagen scaffolds for the treatment of meniscus defects: a systematic review.

Purpose: The purpose of this study was to evaluate the clinical and structural outcomes after resorbable collagen meniscus scaffold implantation through a systematic review of the published literature.

Methods: A systematic search of both the PubMed and Embase databases was undertaken to identify all studies that reported clinical and/or structural outcomes after resorbable collagen meniscus scaffold implantation for the treatment of defects involving either the medial or lateral meniscus. Extracted data included study characteristics; surgical methods and rehabilitation protocols; objective outcomes; and preoperative and postoperative subjective outcome scores including Lysholm, Tegner, International Knee Documentation Committee, and visual analog scale scores.

Outcomes following healing response in older, active patients: a primary anterior cruciate ligament repair technique.

The purpose of this study was to document outcomes following the healing response procedure for treatment of complete, proximal anterior cruciate ligament (ACL) tears in a mature, active population. Healing response is an all-arthroscopic procedure that preserves the native ACL and makes use of an arthroscopic awl with a 45-degree angle to make holes in the femoral attachment of the ACL and in the body of the ACL. Patients were included in this IRB-approved study if they were > or =40 years old, had a complete proximal ACL tear, and who had healing response within 6 weeks of initial injury.

Effects of Platelet-Rich Plasma Composition on Anabolic and Catabolic Activities in Equine Cartilage and Meniscal Explants.

Objective: To evaluate the effects of single- and double-spin preparations of platelet-rich plasma (PRP) on anabolic and catabolic activities of cartilage and meniscal explants in vitro.

Methods: Single- and double-spin PRP was prepared using laboratory processing or commercial kits. The cellular contents were quantified, and each PRP was mixed in equal quantities with cell culture medium and added to cartilage or meniscus explant cultures, with or without interleukin 1 β (IL-1β).

Biological enhancement of meniscus repair and replacement.

When a meniscus injury occurs, it is generally accepted that preserving the meniscus is important for life-long joint preservation. Traditional suture repair of the meniscus has good results; however, the healing potential of meniscus tissue remains as a biological challenge because it is not a completely vascularized structure. For this reason, investigators have continued to search for adjuncts to improve clinical results.

Evaluation of intra-articular mesenchymal stem cells to augment healing of microfractured chondral defects.

Purpose: This study evaluated intra-articular injection of bone marrow-derived mesenchymal stem cells (BMSCs) to augment healing with microfracture compared with microfracture alone.

Methods: Ten horses (aged 2.5 to 5 years) had 1-cm2 defects arthroscopically created on both medial femoral condyles of the stifle joint (analogous to the human knee).

Microfracture: Its History and Experience of the Developing Surgeon.

Development and implementation of the microfracture technique began in the early 1980s. The surgical goal was to produce "microfractures" in the subchondral bone perpendicular to the surface and to be able to reach all areas of the joint with the instruments. The microfracture technique has been demonstrated to be an effective arthroscopic treatment for full-thickness chondral lesions and joints with degenerative lesions.

Rehabilitation following microfracture for chondral injury in the knee.

Full-thickness chondral defects in the knee are common, and these articular cartilage lesions may present in various clinical settings and at different ages. Articular cartilage defects that extend full thickness to subchondral bone rarely - by providing a suitable environment for new tissue formation and takes advantage of the body's own healing potential. Proper surgical technique and rehabilitation improve the success rate of the microfracture procedure.

The reliability, validity, and responsiveness of the Lysholm score and Tegner activity scale for anterior cruciate ligament injuries of the knee: 25 years later.

Background: In 1982, the Lysholm score was first published as a physician-administered score in the American Journal of Sports Medicine. The Tegner activity scale was published in 1985.

Hypothesis: The Lysholm and Tegner scores are valid as patient-administered scores and responsive at early time points after treatment of anterior cruciate ligament tears.

Comparison of the collagen meniscus implant with partial meniscectomy. A prospective randomized trial.

Background: Loss of meniscal tissue leads to increased pain and decreased clinical function and activity levels. We hypothesized that patients receiving a collagen meniscus implant would have better clinical outcomes than patients treated with partial medial meniscectomy alone.

Methods: Three hundred and eleven patients with an irreparable injury of the medial meniscus or a previous partial medial meniscectomy, treated by a total of twenty-six surgeon-investigators at sixteen sites, were enrolled in the study.

Reliability, validity, and responsiveness of the IKDC score for meniscus injuries of the knee.

Purpose: The purpose of this study was to determine the psychometric properties of the International Knee Documentation Committee (IKDC) score for meniscus injuries of the knee.

Methods: Test-retest reliability, content validity, construct validity, and responsiveness to change were determined for the IKDC score. Knees were excluded if they had ligament pathology or a chondral defect greater than Outerbridge grade 2.

Effects of calcified cartilage on healing of chondral defects treated with microfracture in horses.

Background: Microfracture of full-thickness articular defects has been shown to significantly enhance the amount of repair tissue. However, there is a suggestion that leaving calcified cartilage inhibits this repair response.

Hypothesis: Removal of the calcified cartilage with retention of subchondral bone enhances the amount of attachment of the repair tissue compared with retention of the calcified cartilage layer.

Microfracture of the hip in athletes.

Most studies addressing treatment of chondral injuries have involved the knee. Various techniques have been used in the knee. Microfracture has shown excellent results in the knee.

Reliability, validity, and responsiveness of the Lysholm knee score and Tegner activity scale for patients with meniscal injury of the knee.

Background: A torn meniscus is one of the most common indications for knee surgery. The purpose of this study was to determine the psychometric properties of the Lysholm knee score and the Tegner activity scale when used for patients with a meniscal injury of the knee.

Methods: Test-retest reliability, content validity, criterion validity, construct validity, and responsiveness to change were determined for the Lysholm score and the Tegner activity scale.

Healing of a surgically created partial detachment of the posterior cruciate ligament using marrow stimulation: an experimental study in dogs.

The inability of intra-articular (cruciate) ligaments to generate a substantive reparative response may preclude the primary surgical repair of such lesions. A marrow stimulation technique that provides access to a fibrin scaffold, cytokines, and mesenchymal stem cells has been shown to be successful in generating a repair response in articular cartilage. We hypothesized that a similar approach may be effective in initiating and supporting a healing response in cruciate ligament injuries.

A minimally invasive technique ("healing response") to treat proximal ACL injuries in skeletally immature athletes.

This study documents outcomes of athletically active, skeletally immature patients with proximal anterior cruciate ligament (ACL) tears treated with a non-reconstructive technique to promote healing ("healing response"). Between 1992 and 1998, 13 skeletally immature athletes with proximal ACL tears underwent a healing response procedure. Patients with previous ACL injury, other concurrent ligament pathology, and/or complete mid-substance ACL tears were excluded.

Tissue-engineered collagen meniscus implants: 5- to 6-year feasibility study results.

Purpose: In this feasibility study, a 5- to 6-year clinical follow-up evaluation was conducted on 8 patients who had undergone reconstruction of 1 injured medial meniscus with a tissue-engineered collagen meniscus implant. The hypothesis was that these patients would show significant clinical improvement over their preoperative status and would have maintained their status determined at the 2-year follow-up evaluation.

Type Of Study: Prospective longitudinal feasibility study follow-up evaluation.

Patient satisfaction and outcome after microfracture of the degenerative knee.

Satisfaction and functional outcome was measured in 81 patients who were treated arthroscopically with microfracture for isolated degenerative lesions of the knee. Average patient age was 49 years (range: 40-70 years) and average degenerative lesion measured 229.5 mm2 (range: 25-2000 mm2).

Outcomes of microfracture for traumatic chondral defects of the knee: average 11-year follow-up.

Purpose: In this study, we measured functional outcomes of patients treated arthroscopically with microfracture for full-thickness traumatic defects of the knee.

Type Of Study: A case series of patients with 7 to 17 years' follow-up.

Methods: Between 1981 and 1991, a total of 72 patients (75 knees) met the following inclusion criteria: (1) traumatic full-thickness chondral defect, (2) no meniscus or ligament injury, and (3) age 45 years and younger (range, 13 to 45 years).

Early events in cartilage repair after subchondral bone microfracture.

The current study investigated healing of large full-thickness articular cartilage defects during the first 8 weeks with and without penetration of the subchondral bone using microfracture in an established equine model of cartilage healing. Chondral defects in the weightbearing portion of the medial femoral condyle were made bilaterally; one defect in each horse was microfractured whereas the contralateral leg served as the control. The expression of cartilage extracellular matrix components (Types I and II collagen and aggrecan) was evaluated using histologic techniques, reverse transcription coupled polymerase chain reaction, in situ hybridization, and immunohistochemistry.