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Platelet-rich plasma in the pathologic processes of cartilage: review of basic science evidence

Smyth, Niall A; Murawski, Christopher D; Fortier, Lisa A; Cole, Brian J; Kennedy, John G
PURPOSE/OBJECTIVE:The purpose of this study was to systematically review the basic science evidence for the use of platelet-rich plasma (PRP) in the treatment of pathologic processes of cartilage, both as an adjunct to cartilage repair and as a conservative management strategy for osteoarthritis, with the intent of determining the effect of PRP and whether a proof of concept for its use has been established to facilitate further investigation at a clinical level. METHODS:Using the terms "platelet-rich plasma OR PRP OR autologous conditioned plasma OR ACP AND cartilage OR chondrocytes OR chondrogenesis OR osteoarthritis OR arthritis" we searched EMBASE and PubMed/Medline in April 2012. Two authors performed the search, 3 authors independently assessed the studies for inclusion, and 2 authors extracted the data. Extracted data included cytologic analysis of PRP, study design, and results. RESULTS:Twenty-one studies (12 in vitro, 8 in vivo, one in vitro and in vivo) met the inclusion criteria. The effects of PRP in these studies included increasing chondrocyte and mesenchymal stem cell proliferation, proteoglycan deposition, and type II collagen deposition. PRP was also found to increase the cell viability of chondrocytes and the migration and chondrogenic differentiation of mesenchymal stem cells (MSCs) and to inhibit the effect of catabolic cytokines. In vivo, PRP was used as an adjunct to concomitant surgical management, including microfracture surgery and implant, scaffold, and graft insertion. Not all studies concluded that PRP has a positive effect on cartilage repair. CONCLUSIONS:The current basic science evidence suggests that PRP has several potential effects on cartilage repair and osteoarthritis, and a proof of concept has been established. Well-designed randomized controlled trials (RCTs) are needed to extrapolate this evidence to the clinical setting.
PMID: 23669235
ISSN: 1526-3231
CID: 3524032

Hindfoot arthroscopic surgery for posterior ankle impingement: a systematic surgical approach and case series

Smyth, Niall A; Murawski, Christopher D; Levine, David S; Kennedy, John G
BACKGROUND:Hindfoot arthroscopic surgery has been described as a minimally invasive surgical treatment for posterior ankle impingement syndrome. The current article describes a systematic approach for identifying relevant hindfoot structures as well as the clinical results of a case series. PURPOSE/OBJECTIVE:To present a structured systematic surgical approach for identifying relevant anatomic structures and abnormalities during hindfoot arthroscopic surgery. In addition, we report the clinical results of a case series. STUDY DESIGN/METHODS:Case series; Level of evidence, 4. METHODS:The systematic surgical approach divides the extra-articular structures of the hindfoot into quadrants as defined by the intermalleolar ligament. Twenty-two patients underwent hindfoot arthroscopic surgery for the treatment of posterior ankle impingement syndrome. The mean follow-up time was 25 months (range, 14-35 months). Standard patient-reported outcome questionnaires of the foot and ankle outcome score (FAOS) and Short Form-12 (SF-12) general health survey were administered at standard time points after surgery. Return to sporting activities was also calculated as the time period from the date of surgery until the patient was able to participate at their previous level of activity. RESULTS:The mean FAOS score improved from 59 (range, 22-94) preoperatively to 86 (range, 47-100) postoperatively (P < .01). The mean SF-12 score showed similar improvement with a mean of 66 (range, 42-96) preoperatively to 86 (range, 56-98) postoperatively (P < .01). Nineteen patients reported competing at some level of athletic sport before surgery. All patients returned to their previous level of competition after surgery. The mean time to return to sporting activities was 12 weeks (range, 6-16 weeks). Two complications were reported postoperatively: 1 wound infection and 1 case of dysesthesia of the deep peroneal nerve. CONCLUSION/CONCLUSIONS:Hindfoot arthroscopic surgery is a safe and effective treatment strategy for posterior ankle impingement syndrome. In addition, it allows the patients a rapid return to sporting activities.
PMID: 23720445
ISSN: 1552-3365
CID: 3524042

Operative treatment of osteochondral lesions of the talus

Murawski, Christopher D; Kennedy, John G
➤ Osteochondral lesions of the talus are common injuries in recreational and professional athletes, with up to 50% of acute ankle sprains and fractures developing some form of chondral injury. Surgical treatment paradigms aim to restore the articular surface with a repair tissue similar to native cartilage and to provide long-term symptomatic relief.➤ Arthroscopic bone-marrow stimulation techniques, such as microfracture and drilling, perforate the subchondral plate with multiple openings to recruit mesenchymal stem cells from the underlying bone marrow to stimulate the differentiation of fibrocartilaginous repair tissue in the defect site. The ability of fibrocartilage to withstand mechanical loading and protect the subchondral bone over time is a concern.➤ Autologous osteochondral transplantation techniques replace the defect with a tubular unit of viable hyaline cartilage and bone from a donor site in the ipsilateral knee. In rare cases, a graft can also be harvested from the ipsilateral talus or contralateral knee. The limitations of donor site morbidity and the potential need for an osteotomy about the ankle should be considered. Some anterior or far posterior talar lesions can be accessed without arthrotomy or with a plafondplasty.➤ Osteochondral allograft transplantation allows an osteochondral lesion with a large surface area to be replaced with a single unit of viable articular cartilage and subchondral bone from a donor that is matched to size, shape, and surface curvature. The best available evidence suggests that this procedure should be limited to large-volume cystic lesions or salvage procedures.➤ Autologous chondrocyte implantation techniques require a two-stage procedure, the first for chondrocyte harvest and the second for implantation in a periosteum-covered or matrix-induced form after in vivo culture expansion. Theoretically, the transplantation of chondrocyte-like cells into the defect will result in hyaline-like repair tissue.
PMID: 23780543
ISSN: 1535-1386
CID: 3524052

Syndesmosis and lateral ankle sprains in the National Football League

Osbahr, Daryl C; Drakos, Mark C; O'Loughlin, Padhraig F; Lyman, Stephen; Barnes, Ronnie P; Kennedy, John G; Warren, Russell F
Syndesmosis sprains in the National Football League (NFL) can be a persistent source of disability, especially compared with lateral ankle injuries. This study evaluated syndesmosis and lateral ankle sprains in NFL players to allow for better identification and management of these injuries. Syndesmosis and lateral ankle sprains from a single NFL team database were reviewed over a 15-year period, and 32 NFL team physicians completed a questionnaire detailing their management approach. A comparative analysis was performed analyzing several variables, including diagnosis, treatment methods, and time lost from sports participation. Thirty-six syndesmosis and 53 lateral ankle sprains occurred in the cohort of NFL players. The injury mechanism typically resulted from direct impact in the syndesmosis and torsion in the lateral ankle sprain group (P=.034). All players were managed nonoperatively. The mean time lost from participation was 15.4 days in the syndesmosis and 6.5 days in the lateral ankle sprain groups (P⩽.001). National Football League team physicians varied treatment for syndesmosis sprains depending on the category of diastasis but recommended nonoperative management for lateral ankle sprains. Syndesmosis sprains in the NFL can be a source of significant disability compared with lateral ankle sprains. Successful return to play with nonoperative management is frequently achieved for syndesmosis and lateral ankle sprains depending on injury severity. With modern treatment algorithms for syndesmosis sprains, more aggressive nonoperative treatment is advocated. Although the current study shows that syndesmosis injuries require longer rehabilitation periods when compared with lateral ankle sprains, the time lost from participation may not be as prolonged as previously reported.
PMID: 24200441
ISSN: 1938-2367
CID: 3524072

The effect of platelet-rich plasma on autologous osteochondral transplantation: an in vivo rabbit model

Smyth, Niall A; Haleem, Amgad M; Murawski, Christopher D; Do, Huong T; Deland, Jonathan T; Kennedy, John G
BACKGROUND:Autologous osteochondral transplantation restores a cartilage defect with a cylindrical unit of bone and articular cartilage. Previous studies have described poor graft integration at the chondral interface and degeneration of the cartilage. This has prompted the investigation of adjuncts to address these concerns, including platelet-rich plasma (PRP), which has the potential to improve chondral interface integration and decrease cartilage degeneration. The purpose of this study was to evaluate the effect of PRP on autologous osteochondral transplantation in a rabbit model. METHODS:Bilateral osteochondral defects (2.7 mm in diameter and 5 mm in depth) were created on the femoral condyles of twelve New Zealand White rabbits. Osteochondral grafts were harvested from the ipsilateral femoral condyle and, after randomization, were treated with either PRP or saline solution before implantation into the defect site. The rabbits were killed at three, six, or twelve weeks postoperatively. The osteochondral graft was assessed using the International Cartilage Repair Society (ICRS) macroscopic and modified ICRS histological scoring systems. RESULTS:Macroscopic assessment revealed no significant difference between the two groups (mean and standard deviation, 11.2 ± 0.9 for the PRP-treated group versus 10.3 ± 0.9 for the control group; p = 0.09). The mean modified ICRS histological score was significantly higher overall and at each time point for the PRP-treated osteochondral transplants compared with the controls (overall mean, 18.2 ± 2.7 versus 13.5 ± 3.3; p = 0.002). Assessing graft integration specifically, the mean score for the PRP-treated group was significantly higher than that for the control group (2.5 ± 0.9 versus 1.6 ± 0.7; p = 0.004). No adverse events occurred as a result of the surgical procedure or PRP. CONCLUSIONS:PRP may improve the integration of an osteochondral graft at the cartilage interface and decrease graft degeneration in an in vivo animal model. CLINICAL RELEVANCE/CONCLUSIONS:The use of PRP as a biological adjunct to autologous osteochondral transplantation has the clinical potential to enhance graft integration, decrease cartilage degeneration, and improve clinical outcomes of autologous osteochondral transplantation.
PMID: 24352772
ISSN: 1535-1386
CID: 3524082

Platelet-rich plasma as a biological adjunct to the surgical treatment of osteochondral lesions of the talus

Smyth, NA; Fansa, AM; Murawski, CD; Kennedy, John G
Platelet-rich plasma (PRP) has become an increasingly utilized biological adjunct in orthopedics, particularly in sports medicine. Cartilage repair is one such application for which PRP has been utilized. Osteochondral lesions of the talus are common athletic injuries, and they present a difficult clinical problem in part because of the poor biological environment of cartilage healing. The current authors' are investigating the use of PRP with reparative and restorative techniques, including arthroscopic bone marrow stimulation and autologous osteochondral transplantation, respectively. The hypothesis is that the bioactive molecules and growth factors contained within PRP will stimulate a healing response for the differentiation of fibrocartilage such that it resembles a more hyaline-like microstructure, in addition to enhancing bony incorpoaration. In addition to these anabolic pathways, there is also recent evidence to suggest that PRP may inhibit the catabolic processes of arthritis. This article presents the indications and treatment strategy for using PRP in the surgical treatment of osteochondral lesions of the talus
ORIGINAL:0013327
ISSN: 1536-0644
CID: 3702422

The lateral dorsal cutaneous branch of the sural nerve: clinical importance of the surgical approach to proximal fifth metatarsal fracture fixation

Fansa, Ashraf M; Smyth, Niall A; Murawski, Christopher D; Kennedy, John G
BACKGROUND:Fractures of the proximal fifth metatarsal are one of the most common forefoot injuries encountered by orthopaedic surgeons in sports medicine. The percutaneous surgical approach to Jones fracture fixation and corresponding anatomy has received little attention in the literature to date. PURPOSE/OBJECTIVE:To describe in detail the location of the lateral dorsal cutaneous nerve (LDCN) and its branches relative to the base of the fifth metatarsal and to the standard lateral approach. STUDY DESIGN/METHODS:Descriptive laboratory study. METHODS:Ten fresh-frozen cadaveric foot specimens were used for this study. Specimens were dissected at the lateral aspect of the foot over the proximal fifth metatarsal, and the LDCN and its branches were identified. The distance of the LDCN to the superior border of the peroneus brevis tendon (PBT) was measured relative to standard reference points in all specimens, and the presence of an anastomotic branch was noted. A set of vertical and horizontal reference lines were also constructed to determine whether the LDCN or its branches would be compromised by a standard lateral approach. RESULTS:The LDCN was superficial (ie, lateral) and inferior to the superior border of the PBT in all specimens and at all reference points. A bifurcation of the LDCN was present in 8 specimens, located an average of 18 mm posterior and 11 mm dorsal to the base of the fifth metatarsal. The dorsolateral branch and dorsomedial branch of the LDCN each intersected with the base of the fifth metatarsal horizontal line and vertical line, respectively, indicating potential compromise of the nerve with a standard lateral surgical approach. CONCLUSION/CONCLUSIONS:The standard lateral approach to the base of the fifth metatarsal carries a higher risk for surgical injury to the LDCN. A "high and inside" approach that remains superior to the superior border of the PBT is anatomically safe and may decrease the chance of intraoperative nerve injury and irritation postoperatively.
PMID: 22679294
ISSN: 1552-3365
CID: 3523902

Establishing proof of concept: Platelet-rich plasma and bone marrow aspirate concentrate may improve cartilage repair following surgical treatment for osteochondral lesions of the talus

Smyth, Niall A; Murawski, Christopher D; Haleem, Amgad M; Hannon, Charles P; Savage-Elliott, Ian; Kennedy, John G
Osteochondral lesions of the talus are common injuries in the athletic patient. They present a challenging clinical problem as cartilage has a poor potential for healing. Current surgical treatments consist of reparative (microfracture) or replacement (autologous osteochondral graft) strategies and demonstrate good clinical outcomes at the short and medium term follow-up. Radiological findings and second-look arthroscopy however, indicate possible poor cartilage repair with evidence of fibrous infill and fissuring of the regenerative tissue following microfracture. Longer-term follow-up echoes these findings as it demonstrates a decline in clinical outcome. The nature of the cartilage repair that occurs for an osteochondral graft to become integrated with the native surround tissue is also of concern. Studies have shown evidence of poor cartilage integration, with chondrocyte death at the periphery of the graft, possibly causing cyst formation due to synovial fluid ingress. Biological adjuncts, in the form of platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC), have been investigated with regard to their potential in improving cartilage repair in both in vitro and in vitro settings. The in vitro literature indicates that these biological adjuncts may increase chondrocyte proliferation as well as synthetic capability, while limiting the catabolic effects of an inflammatory joint environment. These findings have been extrapolated to in vitro animal models, with results showing that both PRP and BMAC improve cartilage repair. The basic science literature therefore establishes the proof of concept that biological adjuncts may improve cartilage repair when used in conjunction with reparative and replacement treatment strategies for osteochondral lesions of the talus.
PMID: 22816065
ISSN: 2218-5836
CID: 3523912

Anatomic lateral ligament reconstruction in the ankle: a hybrid technique in the athletic population

Kennedy, John G; Smyth, Niall A; Fansa, Ashraf M; Murawski, Christopher D
BACKGROUND:Anatomic and checkrein tenodesis reconstruction techniques have been described as a means of treatment for chronic lateral ligament instability in the ankle. The current article describes a hybrid procedure using the most advantageous concepts of both techniques for use when insufficient normal ligament remains to fashion a direct repair of the anterior talofibular ligament (ATFL). PURPOSE/OBJECTIVE:The authors report the results at a minimum 1-year follow-up of 57 patients who underwent a hybrid anatomic lateral ligament reconstruction technique in the ankle. STUDY DESIGN/METHODS:Case series; Level of evidence, 4. METHODS:Fifty-seven patients underwent a hybrid anatomic lateral ligament reconstruction procedure under the care of the senior author. All patients were assessed preoperatively and postoperatively using the Foot and Ankle Outcome Score (FAOS) and Short Form-12 (SF-12) outcome score. The mean patient age at the time of surgery was 28 years (range, 17-65 years), including 39 male and 18 female patients. The mean follow-up time was 32 months (range, 12-47 months). RESULTS:The FAOS improved from 58 points preoperatively to 89 points postoperatively (P < .01). The SF-12 score improved from 48 points before surgery to 80 points at final follow-up (P < .01). All patients achieved mechanical stability at final clinical follow-up; 7 patients (12%) demonstrated functional instability. Functional instability was found to significantly influence not returning to sport at the previous level. CONCLUSION/CONCLUSIONS:This hybrid anatomic lateral ligament reconstruction technique using a peroneus longus autograft to substitute the native ATFL provides an alternative to anatomic reconstruction when direct repair is not possible.
PMID: 22879402
ISSN: 1552-3365
CID: 3523932

Critical defect size for osteochondral lesions of the talus: letter to the editor [Letter]

Hannon, Charles P; Murawski, Christopher D; Smyth, Niall A; Kennedy, John G
PMID: 22941577
ISSN: 1552-3365
CID: 3523942