Radiofrequency Microtenotomy for Elbow Epicondylitis: Midterm Results.

We conducted a prospective, nonrandomized, single-center clinical study to evaluate the safety and midterm effectiveness of microtenotomy using a radiofrequency probe to treat chronic tendinosis of the elbow. All patients had failed conservative treatment for 6 months. The radiofrequency-based microtenotomy was performed using the Topaz Microdebrider (ArthroCare).

Osteochondral allograft transplantation in cartilage repair: Graft storage paradigm, translational models, and clinical applications.

The treatment of articular cartilage injury and disease has become an increasingly relevant part of orthopaedic care. Articular cartilage transplantation, in the form of osteochondral allografting, is one of the most established techniques for restoration of articular cartilage. Our research efforts over the last two decades have supported the transformation of this procedure from experimental "niche" status to a cornerstone of orthopaedic practice.

Radiofrequency stimulation for potential healing of meniscal injuries in the avascular zone.

We conducted this study to evaluate the effect of radiofrequency (RF) stimulation with suture repair on the healing of tears in the meniscal white-white zone. Fifty-four New Zealand white rabbits underwent surgically induced meniscal injuries within the white-white region. RF was applied using a 0.

Development of a Comprehensive Osteochondral Allograft MRI Scoring System (OCAMRISS) with Histopathologic, Micro-Computed Tomography, and Biomechanical Validation.

Objective: To describe and apply a semi-quantitative MRI scoring system for multi-feature analysis of cartilage defect repair in the knee by osteochondral allografts, and to correlate this scoring system with histopathologic, micro-computed tomography (μCT), and biomechanical reference standards using a goat repair model.

Design: Fourteen adult goats had two osteochondral allografts implanted into each knee: one in the medial femoral condyle (MFC) and one in the lateral trochlea (LT). At 12 months, goats were euthanized and MRI was performed.

Use of platelet-rich plasma to enhance tendon function and cellularity.

Clinical studies have shown inconsistent healing with subjective improvement after use of platelet-rich plasma (PRP) for tendinosis and partial tendon tears. We conducted a study to assess changes after injecting PRP into an intact rabbit patellar tendon (PT) model. In the study group (n = 10), an incision was made over the PT and PRP was injected into multiple sites on the PT.

A biomechanical assessment of tendon repair after radiofrequency treatment.

After acute tendon injury, rapid mobilization prevents adhesions and improves the ultimate strength of the repair. Radiofrequency (RF) ablation is proposed to enhance angiogenesis in the early stages of healing. The mechanism and effect of RF have not yet been described in an animal model of tendon injury.

Treatment of articular cartilage defects in the goat with frozen versus fresh osteochondral allografts: effects on cartilage stiffness, zonal composition, and structure at six months.

Background: Understanding the effectiveness of frozen as compared with fresh osteochondral allografts at six months after surgery and the resultant consequences of traditional freezing may facilitate in vivo maintenance of cartilage integrity. Our hypothesis was that the state of the allograft at implantation affects its performance after six months in vivo.

Methods: The effect of frozen as compared with fresh storage on in vivo allograft performance was determined for osteochondral allografts that were transplanted into seven recipient goats and analyzed at six months.

Augmentation of tendon healing with butyric acid-impregnated sutures: biomechanical evaluation in a rabbit model.

Background: Butyric acid (BA) has been shown to be angiogenic and to enhance transcriptional activity in tissue. These properties of BA have the potential to augment biological healing of a repaired tendon.

Purpose: To evaluate this possibility both biomechanically and histologically in an animal tendon repair model.

The in vivo performance of osteochondral allografts in the goat is diminished with extended storage and decreased cartilage cellularity.

Background: Currently, osteochondral allografts (OCA) are typically used after 4°C storage for prolonged durations (15-43 days), which compromises chondrocyte viability, especially at the articular surface. The long-term in vivo performance of these fresh-stored allografts, in association with variable cellularity, is unknown.

Purpose: To determine the effect of 4°C storage duration (14, 28 days) versus the best (fresh) and worst (frozen) conditions of chondrocyte viability on structure, composition, and function of cartilage in the goat and the association of retrieved chondrocyte cellularity with those tissue properties.

The effect of butyric acid on normal tendons: a potential stimulus for extracellular matrix expression.

We propose comparing angiogenic effects of butyric acid (BA)-impregnated suture vs control suture on an aged tendon model. Twenty-four 3-year-old rabbits underwent bilateral Achilles tendon exposure. BA-impregnated orthopedic suture was sutured into one side, and a control orthopedic suture into the contralateral side similarly.

Effect of light-emitting diode (LED) therapy on the development of osteoarthritis (OA) in a rabbit model.

Objective: The objective of this study was to evaluate whether light-emitting diodes (LEDs) could be effective in a noninvasive, therapeutic device for the treatment of osteoarthritic (OA) knee joints.

Design: Five weeks following the anterior cruciate ligament transection (ACLT) of mature New Zealand White rabbits, the animal knees were exposed to LED stimulation at intervals of 10 min/day, 5 days/week for 5 weeks in the experimental group (n=7). The device used high intensity red and infrared (IR) LEDs with a total amount of energy delivered to the skin of 2.

Etanercept enhances preservation of osteochondral allograft viability.

Background: Osteochondral allografts are an increasingly popular treatment for the repair of articular cartilage lesions. Current tissue bank protocols require bacteriological testing that takes from 21 to 28 days to process. During this time, tumor necrosis factor-alpha (TNF-α, a proapoptotic cytokine) is upregulated, resulting in loss of chondrocyte viability.

The effects of exogenous basic fibroblast growth factor on intrasynovial flexor tendon healing in a canine model.

Background: Studies have demonstrated that flexor tendon repair strength fails to increase in the first three weeks following suturing of the tendon, a finding that correlates closely with the timing of many clinical failures. The application of growth factors holds promise for improving the tendon-repair response and obviating failure in the initial three weeks.

Methods: The effects of basic fibroblast growth factor on flexor tendon healing were evaluated with use of a canine model.

Can osteochondral grafting be augmented with microfracture in an extended-size lesion of articular cartilage?

Background: Both microfracture and osteochondral autografting procedures have been useful in treating osteochondral lesions.

Hypothesis: Combining microfracture and osteochondral autografting procedures can extend the size of lesions that can be treated with either technique.

Study Design: Descriptive laboratory study.

Changes in condylar coefficient of friction after osteochondral graft transplantation and modulation with hyaluronan.

Purpose: To better understand the changes in the cartilage coefficient of friction (COF) after an osteochondral repair, an assessment of dynamic loads has been developed using a goat knee model. The application of hyaluronan (HA) was also assessed for its lubricative properties and the resulting COF of the knee after osteochondral repair.

Methods: A total of 18 caprine knees were dissected and mounted into an Instron load frame (Instron, Norwood, MA) for testing.

Enhanced flexor tendon healing through controlled delivery of PDGF-BB.

A fibrin/heparin-based delivery system was used to provide controlled delivery of platelet derived growth factor BB (PDGF-BB) in an animal model of intrasynovial flexor tendon repair. We hypothesized that PDGF-BB, administered in this manner, would stimulate cell proliferation and matrix remodeling, leading to improvements in the sutured tendon's functional and structural properties. Fifty-six flexor digitorum profundus tendons were injured and repaired in 28 dogs.

Variation of mesenchymal cells in polylactic acid scaffold in an osteochondral repair model.

Objective: To achieve osteochondral regeneration utilizing transplantation of cartilage-lineage cells and adequate scaffolds, it is essential to characterize the behavior of transplanted cells in the repair process. The objectives of this study were to elucidate the survival of mesenchymal cells (MCs). In a polylactic acid (PLA) scaffold and assess the possibility of MC/PLA constructs for osteochondral repair.

Controlled-release kinetics and biologic activity of platelet-derived growth factor-BB for use in flexor tendon repair.

Purpose: Surgically repaired intrasynovial tendons are at greatest risk of failure in the first 3 weeks after surgery. Attempts to improve the strength of repair by modifying rehabilitation parameters have not always been successful. Manipulation of the biological environment of the sutured tendon holds great promise for accelerating the repair process.

Use of bone morphogenic protein-7 as a treatment for osteoarthritis.

Osteoarthritis is a degenerative disorder resulting from breakdown of articular cartilage. Previous work has shown bone morphogenic protein-7 has a potential protective effect on cartilage during the development of osteoarthritis. The purpose of this study was to determine whether bone morphogenic protein-7 could decrease the amount of cartilage degradation in preexisting osteoarthritis.

Effects of biglycan deficiency on myocardial infarct structure and mechanics.

Biglycan, a small leucine-rich proteoglycan, has been shown to interact with extracellular matrix (ECM) collagen and may influence fibrillogenesis. We hypothesized that biglycan contributes to post-myocardial infarction (MI) scar development and that the absence of biglycan would result in altered scar structure and mechanics. Anterior MI was induced in biglycan hemizygous null and wild-type mice by permanent ligation of the left coronary artery.

Spinal growth modulation with an anterolateral flexible tether in an immature bovine model: disc health and motion preservation.

Study Design: An immature bovine model was used to evaluate multilevel anterolateral flexible tethering in a growing spine.

Objective: To evaluate radiographic, biochemical, histologic, and biomechanical results of tethered spinal growth.

Summary Of Background Data: An anterolateral flexible tether has been shown to create a kyphotic and scoliotic spinal deformity in calves.

Analysis of cartilage tissue on a cellular level in fresh osteochondral allograft retrievals.

Background: Fresh human osteochondral allografting is a biological cartilage replacement technique used to treat articular and osteoarticular defects in the knee. A small number of grafts fail, and we analyzed every retrieved graft during a 4-year period in order to learn more about the potential causes of failure.

Hypothesis: A large percentage of chondrocytes still remain viable many years after fresh osteochondral allografting.

Nerve regeneration after radiofrequency application.

Background: Many patients with chronic tendinosis have experienced early pain relief after application of bipolar radiofrequency treatment. It is hypothesized that the mechanism of action may be the acute degeneration and/or ablation of sensory nerve fibers.

Hypothesis: After ablation or degeneration by bipolar radiofrequency, nerve fibers will have the ability to regenerate with time.

PDGF-BB released in tendon repair using a novel delivery system promotes cell proliferation and collagen remodeling.

The purpose of this study was to promote fibroblast proliferation and collagen remodeling in flexor tendon repair through sustained delivery of platelet derived growth factor (PDGF-BB). The release kinetics of PDGF-BB from a novel fibrin matrix delivery system was initially evaluated in vitro. After the in vivo degradation rate of the fibrin matrix was determined using fluorescently tagged fibrin, PDGF-BB was delivered to the site of flexor tendon repair in vivo in a canine model.

Role of apoptotic and matrix-degrading genes in articular cartilage and meniscus of mature and aged rabbits during development of osteoarthritis.

Objective: To determine expression patterns of apoptotic and matrix-degrading genes during aging and development of osteoarthritis (OA), using a rabbit model of induced OA.

Methods: Six mature and 6 aged rabbits underwent anterior cruciate ligament transection and were killed 4 and 8 weeks after surgery, respectively, to create early-grade and advanced-grade OA. RNA from articular cartilage and menisci was examined for expression of the genes caspase 8, Fas, Fas ligand, p53, aggrecanase, matrix metalloproteinase 1 (MMP-1), and MMP-3.