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Platelet-Rich Plasma in the Animal Long-Bone Model: An Analysis of Basic Science Evidence
Gianakos, Arianna; Zambrana, Lester; Savage-Elliott, Ian; Lane, Joseph M; Kennedy, John G
Platelet-rich plasma (PRP) has been suggested as an adjunct to aid in long-bone healing. The purpose of this study was to systematically review the basic science in vivo evidence for the use of PRP in the treatment of bone pathology. The PubMed/MEDLINE and EMBASE databases were screened using the following search criteria: "(Platelet-rich plasma OR PRP OR autologous conditioned plasma OR ACP) AND (bone OR osteocytes OR osteogenesis OR nonunion OR delayed union)." Studies were included if they fulfilled the following criteria: (1) studied the effect of PRP or a similar concentrated platelet product, defined as a blood product with platelet concentration elevated to higher than baseline; (2) established a control with which to compare PRP; (3) were published in a peer-reviewed journal; and (4) looked specifically at animal long-bone models. All review articles and clinical studies, including randomized controlled trials and case series, were excluded from the review. Studies examining the effects of PRP on bones of animals with confounding pathology were excluded. In studies that contained additional treatment variables, only the portion of the experiment that compared PRP directly with the control were evaluated. Data were then extracted with a standardized table. The search yielded 29 articles for inclusion. Seventy-two percent of the studies reported platelet concentrations. Eighty-nine percent of studies reported significant improvement in earlier bone healing on histologic/histomorphometric assessment. One hundred percent showed significant increase in bone formation on radiographs in the PRP group. Eighty percent of studies reported a significant increase in bone area on microcomputed tomography. One hundred percent of studies showed a higher torsional stiffness for the PRP-treated defects. In the in vivo studies evaluated, PRP confers several beneficial effects on animal long-bone models. Proof of concept for PRP as a biologic adjunct in long-bone models has been determined.
PMID: 26652328
ISSN: 1938-2367
CID: 3524302
Platelet-rich plasma increases transforming growth factor-beta1 expression at graft-host interface following autologous osteochondral transplantation in a rabbit model
Boakye, Lorraine A; Ross, Keir A; Pinski, John M; Smyth, Niall A; Haleem, Amgad M; Hannon, Charles P; Fortier, Lisa A; Kennedy, John G
AIM/OBJECTIVE:To explore the effect of platelet-rich plasma on protein expression patterns of transforming growth factor-beta1 (TGF-β1) in cartilage following autologous osteochondral transplantation (AOT) in a rabbit knee cartilage defect model. METHODS:Twelve New Zealand white rabbits received bilateral AOT. In each rabbit, one knee was randomized to receive an autologous platelet rich plasma (PRP) injection and the contralateral knee received saline injection. Rabbits were euthanized at 3, 6 and 12 wk post-operatively. Articular cartilage sections were stained with TGF-β1 antibody. Histological regions of interest (ROI) (left, right and center of the autologous grafts interfaces) were evaluated using MetaMorph. Percentage of chondrocytes positive for TGF-β1 was then assessed. RESULTS:Percentage of chondrocytes positive for TGF-β1 was higher in PRP treated knees for selected ROIs (left; P = 0.03, center; P = 0.05) compared to control and was also higher in the PRP group at each post-operative time point (P = 6.6 × 10(-4), 3.1 × 10(-4) and 7.3 × 10(-3) for 3, 6 and 12 wk, respectively). TGF-β1 expression was higher in chondrocytes of PRP-treated knees (36% ± 29% vs 15% ± 18%) (P = 1.8 × 10(-6)) overall for each post-operative time point and ROI. CONCLUSION/CONCLUSIONS:Articular cartilage of rabbits treated with AOT and PRP exhibit increased TGF-β1 expression compared to those treated with AOT and saline. Our findings suggest that adjunctive PRP may increase TGF-β1 expression, which may play a role in the chondrogenic effect of PRP in vivo.
PMID: 26716092
ISSN: 2218-5836
CID: 3524352
Functional Outcomes of Tibialis Posterior Tendoscopy With Comparison to Magnetic Resonance Imaging
Gianakos, Arianna L; Ross, Keir A; Hannon, Charles P; Duke, Gavin L; Prado, Marcelo P; Kennedy, John G
BACKGROUND: The purpose of the current study was to report functional outcomes of tendoscopy for treatment of tibialis posterior tendon pathology as well as compare its diagnostic capability with magnetic resonance imaging (MRI). METHODS: Clinical records and MRI of 12 patients who underwent tendoscopy of the tibialis posterior tendon (TPT) were retrospectively reviewed. Mean follow-up was 31 months (range, 26-43 months). Preoperative MRI findings were compared with tendoscopic findings to assess the diagnostic agreement between each modality. Functional outcomes were assessed using the Foot and Ankle Outcome Score (FAOS) and Short Form-12 (SF-12) General Health Questionnaire pre- and postoperatively. Mean patient age was 43 years (range, 17-63 years). Mean duration of preoperative symptoms was 15.5 months (range, 3-36 months). RESULTS: Pathologies addressed via tendoscopy included tenosynovitis, tendinosis, stenosis, tendon subluxation, and partial thickness tear (via mini-arthrotomy). Preoperative MRI findings were in agreement with tendoscopic findings in 8 of 12 cases (67%). Tendoscopy diagnosed and allowed access for treating pathology that was missed on MRI in the remaining four cases. The FAOS improved from a mean preoperative score of 58 (range, 36-78) to a mean postoperative score of 81 (range, 44-98) (P < .01). The SF-12 score improved from a mean preoperative score of 34 (range, 13-51) to a mean postoperative score of 51 (range, 21-76) (P = .01). CONCLUSIONS: Although MRI is considered an effective imaging technique for tendon pathology, tendoscopy may be a more sensitive diagnostic tool. Tendoscopy was an effective minimally invasive tool to diagnose and treat tibialis posterior tendon pathology resulting in functional improvements in the short-term for early stage TPT dysfunction. Further studies comparing tendoscopy with traditional open approaches are warranted. LEVEL OF EVIDENCE: Level IV Case Series.
PMID: 25759276
ISSN: 1071-1007
CID: 1494942
Talar osteochondral defects : diagnosis, planning, treatment, and rehabilitation
Dijk, C; Kennedy, John G
Heidelberg : Springer ; Luxembourg : ESSKA, [2014]
Extent: xiii, 155 p.
ISBN: 9783642450983
CID: 3702722
Osteochondral lesions of the talus: aspects of current management
Hannon, C P; Smyth, N A; Murawski, C D; Savage-Elliott, I; Deyer, T W; Calder, J D F; Kennedy, J G
Osteochondral lesions (OCLs) occur in up to 70% of sprains and fractures involving the ankle. Atraumatic aetiologies have also been described. Techniques such as microfracture, and replacement strategies such as autologous osteochondral transplantation, or autologous chondrocyte implantation are the major forms of surgical treatment. Current literature suggests that microfracture is indicated for lesions up to 15 mm in diameter, with replacement strategies indicated for larger or cystic lesions. Short- and medium-term results have been reported, where concerns over potential deterioration of fibrocartilage leads to a need for long-term evaluation. Biological augmentation may also be used in the treatment of OCLs, as they potentially enhance the biological environment for a natural healing response. Further research is required to establish the critical size of defect, beyond which replacement strategies should be used, as well as the most appropriate use of biological augmentation. This paper reviews the current evidence for surgical management and use of biological adjuncts for treatment of osteochondral lesions of the talus.
PMID: 24493179
ISSN: 2049-4408
CID: 3702032
A prospective comparison of 3 approved systems for autologous bone marrow concentration demonstrated nonequivalency in progenitor cell number and concentration
Hegde, Vishal; Shonuga, Owolabi; Ellis, Scott; Fragomen, Austin; Kennedy, John; Kudryashov, Valery; Lane, Joseph M
OBJECTIVES/OBJECTIVE:To evaluate the efficacy of 3 commercially available systems: the Harvest SmartPReP 2 BMAC, Biomet BioCUE, and Arteriocyte Magellan systems. We compared the number and concentration of progenitor cells achieved both before and after centrifugation and the percentage of progenitor cells salvaged after centrifugation. METHODS:Forty patients, mean age 47 ± 18 years (range: 18-92 years, 19 male/21 female) were prospectively consented for bilateral iliac crest aspiration. The first 20 aspirations compared the Harvest and Biomet systems, and based on those results, the second 20 compared the Harvest and Arteriocyte systems. One system was randomly assigned to each iliac crest. Each system's unique marrow acquisition process and centrifugation mechanism was followed. Samples for analysis were taken both immediately before the marrow was put into the centrifugation system (after acquisition), and after centrifugation. The number of progenitor cells in each sample was estimated by counting the connective tissue progenitors (CTPs). RESULTS:The Harvest system achieved a significantly greater number and concentration of CTPs both before and after centrifugation when compared to the Biomet system. There was no difference in the percent yield of CTPs after centrifugation. There was no significant difference in the number and concentration of CTPs between the Harvest and Arteriocyte systems before centrifugation, but the Harvest system had a significantly greater number and concentration of CTPs after centrifugation. The Harvest system also had a significantly higher percent yield of CTPs after centrifugation compared with the Arteriocyte system. CONCLUSIONS:The Harvest system resulted in a greater CTP number and concentration after centrifugation when compared with the Biomet and Arteriocyte systems and may thus provide increased osteogenic and chondrogenic capacity.
PMID: 24694554
ISSN: 1531-2291
CID: 3702022
Posterior hindfoot arthroscopy: a review
Smyth, Niall A; Zwiers, Ruben; Wiegerinck, Johannes I; Hannon, Charles P; Murawski, Christopher D; van Dijk, C Niek; Kennedy, John G
In recent years, minimally invasive surgery has developed and progressed the standard of care in orthopaedics and sports medicine. In particular, the use of posterior hindfoot arthroscopy in the treatment of posterior ankle and hindfoot injury is increasing rapidly as a means of reducing pain, infection rates, and blood loss postoperatively compared with traditional open procedures. In athletes, hindfoot arthroscopy has been used effectively in expediting rehabilitation and ultimately in minimizing the time lost from competition at previous levels. Van Dijk et al were the first to describe the original 2-portal technique, which remains the most commonly used by surgeons today and forms the basis for this review. The current evidence in the literature supports the use of 2-portal hindfoot arthroscopy as a safe, primary treatment strategy for symptoms of posterior ankle impingement, including resection of os trigonum, treatment of flexor hallucis longus and peroneal tendon injury, treatment of osteochondral lesions of the ankle, and the resection of subtalar coalitions. In this review, we present where possible an evidence-based literature review on the arthroscopic treatment of posterior ankle and hindfoot abnormalities. Causes, diagnosis, surgical technique, outcomes, and complications are each discussed in turn.
PMID: 23868522
ISSN: 1552-3365
CID: 3524062
A single platelet-rich plasma injection for chronic midsubstance achilles tendinopathy: a retrospective preliminary analysis
Murawski, Christopher D; Smyth, Niall A; Newman, Hunter; Kennedy, John G
UNLABELLED:The purpose of this study was to evaluate a series of patients undergoing a single platelet-rich plasma (PRP) injection for the treatment of chronic midsubstance Achilles tendinopathy, in whom conservative treatment had failed. Thirty-two patients underwent a single PRP injection for the treatment of chronic midsubstance Achilles tendinopathy and were evaluated at a 6-month final follow-up using the Foot and Ankle Outcome Score and Short Form 12 general health questionnaire. Magnetic resonance imaging was performed on all patients prior to and 6 months after injection. Twenty-five of 32 patients (78%) reported that they were asymptomatic at the 6-month follow-up visit and were able to participate in their respective sports and daily activities. The remaining 7 patients (22%) who reported symptoms that did not improve after 6 months ultimately required surgery. Four patients went on to have an Achilles tendoscopy, while the other 3 had an open debridement via a tendon splitting approach. A retrospective evaluation of patients receiving a single PRP injection for chronic midsubstance Achilles tendinopathy revealed that 78% had experienced clinical improvement and had avoided surgical intervention at 6-month follow-up. LEVELS OF EVIDENCE/METHODS:Therapeutic, Level IV: Retrospective case series.
PMID: 24771019
ISSN: 1938-7636
CID: 3524092
Talonavicular arthroscopy for osteochondral lesions: technique and case series
Ross, Keir A; Seaworth, Christine M; Smyth, Niall A; Ling, Jeffrey S; Sayres, Stephanie C; Kennedy, John G
BACKGROUND:Traditional treatment of talonavicular osteochondral lesions (OCLs) requires an open procedure. Arthroscopic microfracture of talonavicular OCLs may provide a viable, minimally invasive approach. The purpose of this study was to describe an arthroscopic approach for treatment of talonavicular OCLs, describe the proximity of arthroscopic portals to important structures in cadaver specimens, and report magnetic resonance imaging (MRI) findings and clinical outcomes of this technique. METHODS:Five cadaver specimens were dissected so proximity of portals to adjacent tendons and neurovascular structures could be assessed. Subsequently, 3 athletic patients with OCLs of the talonavicular joint were treated with arthroscopic debridement and microfracture. Patient records and imaging studies were retrospectively reviewed. RESULTS:In the cadaver specimens, the mean distance between the neurovascular bundle and the medial border of the extensor hallucis longus (EHL) was 9.0 (range, 8 to 10) mm. The saphenous nerve was located a mean of 6.8 (range, 6 to 7) mm from the medial border of the tibialis anterior tendon. Therefore, portals were placed just medial to the EHL and tibialis anterior tendon to avoid the neurovascular bundle and saphenous nerve, respectively. In all patients, access, identification of the OCL, debridement, and microfracture were successfully performed. All patients demonstrated improvements in Foot and Ankle Outcome Scores and Short Form-12 scores and began gradual return to activity within 12 weeks following the operation. No significant complications occurred. MRI indicated signal consistent with reparative fibrocartilage in all patients. CONCLUSION/CONCLUSIONS:Talonavicular arthroscopy allowed visualization, curettage, synovectomy, loose body removal, and microfracture of OCLs that would have otherwise required an open approach. At early follow-up, all patients had returned to their previous activity levels. Arthroscopy of the talonavicular joint was a viable approach for microfracture of OCLs. LEVEL OF EVIDENCE/METHODS:Level IV, case series.
PMID: 24962526
ISSN: 1944-7876
CID: 3524102
Osteochondral lesions of the talus: a current concepts review and evidence-based treatment paradigm
Savage-Elliott, Ian; Ross, Keir A; Smyth, Niall A; Murawski, Christopher D; Kennedy, John G
UNLABELLED:Osteochondral lesions of the talar dome are increasingly diagnosed and are a difficult pathology to treat. Conservative treatment yields best results in pediatric patients, often leaving surgical options for adult populations. There is a paucity of long-term data and comparisons of treatment options. Arthroscopic bone marrow stimulation is a common first-line treatment for smaller lesions. Despite promising short to medium term clinical results, bone marrow stimulation results in fibrocartilagenous tissue that incurs differing mechanical and biological properties compared with normal cartilage. Autologous osteochondral transplantation has demonstrated promising clinical results in the short to medium term for larger, cystic lesions and can restore the contact pressure of the joint. However, concerns remain over postoperative cyst formation and donor site morbidity. Recent developments have emphasized the usefulness of biological adjuncts such as platelet-rich plasma and concentrated bone marrow aspirate, as well as particulate juvenile cartilage, in augmenting reparative and replacement strategies in osteochondral lesion treatment. The purpose of this article is to review diagnosis and treatment of talar osteochondral lesions so that current practice guidelines can be more efficiently used given the available treatment strategies. A treatment paradigm based on current evidence is described. LEVELS OF EVIDENCE/METHODS:Therapeutic, Level V, Expert Opinion.
PMID: 25100765
ISSN: 1938-7636
CID: 3524112