Niall A. Smyth

Osteochondral lesions of the talus

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.

Platelet-rich plasma in tendon models: a systematic review of basic science literature.

PURPOSE To perform a systematic review of the basic science literature on the use of platelet-rich plasma (PRP) in tendon models. METHODS We searched the PubMed/Medline and Embase databases in June 2012 using the following parameters: ((tenocytes OR tendon OR tendinitis OR tendinosis OR tendinopathy) AND (platelet rich plasma OR PRP OR autologous conditioned plasma OR ACP)). The inclusion criteria for full-text review were in vivo and in vitro studies examining the effects of PRP on tendons and/or tenocytes. Clinical studies were excluded. Only studies published in peer-reviewed journals that compared PRP directly with a control were included. Data were extracted based on a predefined data sheet, which included information on PRP preparation, study methods, and results. Studies were analyzed for trends, comparing and contrasting the reported effects of PRP. RESULTS The search yielded 31 articles for inclusion in our review. Of the studies, 22 (71%) reported platelet concentrations in the PRP; 6 (19%) reported cytology. Eight in vivo studies found decreased tendon repair time, increased fiber organization, or both with PRP treatment. Eight in vitro studies reported that PRP treatment increased cell proliferation; 7 reported an increase in growth factor expression. Three in vivo studies found increased vascularity, and 4 found increased tensile strength with PRP treatment. CONCLUSIONS In the basic science studies evaluated, it appears that PRP confers several potential effects on tendon models compared with a control. However, the literature is inconsistent with regard to reporting the methods of preparation of PRP and in reporting platelet concentrations and cytology. CLINICAL RELEVANCE Establishing proof of concept for PRP may lead to further high-quality clinical studies in which the appropriate indications can be defined.

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

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.

Osteochondral Lesions of the Talus: A Current Concepts Review and Evidence-Based Treatment Paradigm

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: Therapeutic, Level V, Expert Opinion

The deltoid ligament: an in-depth review of anatomy, function, and treatment strategies

PurposeA literature review of the deltoid ligament was conducted, examining the current literature on anatomy, function, and treatment strategies. In particular, anatomical inconsistencies within the literature were evaluated, and detailed anatomical dissections are presented.MethodsA literature search was conducted on PubMed using keywords relevant to the deltoid ligament in the ankle and medial ankle instability. Primary research articles, as well as appropriate summary articles, were selected for review.ResultsWhile it is well defined that the deltoid is contiguous and divided into one superficial and one deep portion, the creation of the individual fibres may be artificial. Furthermore, while improvements in imaging techniques and arthroscopy have not led to a consensus on the anatomy of the ligament, they may help improve recognition of deltoid injuries. Once identified, the majority of deltoid injuries can be treated via conservative treatment. However, reparative and reconstructive treatment strategies can also be used for complex acute injuries or chronic medial ankle instability.ConclusionGiven the continuing evolution of the anatomical understanding of the ligament, the current treatment protocol for deltoid injuries requires further standardization, with an emphasis on proper diagnosis.

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

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 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.

Arthroscopic Bone Marrow Stimulation and Concentrated Bone Marrow Aspirate for Osteochondral Lesions of the Talus: A Case-Control Study of Functional and Magnetic Resonance Observation of Cartilage Repair Tissue Outcomes.

PURPOSE This study compares retrospective functional and magnetic resonance imaging (MRI) outcomes after arthroscopic bone marrow stimulation (BMS) with and without concentrated bone marrow aspirate (cBMA) as a biological adjunct to the surgical treatment of osteochondral lesions (OCLs) of the talus. METHODS Twenty-two patients who underwent arthroscopic BMS with cBMA (cBMA/BMS group) for an osteochondral lesion (OCL) of the talus and 12 patients who underwent arthroscopic BMS (BMS alone) for an OCL of the talus were retrospectively reviewed. The Foot and Ankle Outcome Score (FAOS) pain subscale and Short Form 12 general health questionnaire physical component summary score (SF-12 PCS) provided patient-reported outcome scores pre- and postoperatively. MRI scans were assessed postoperatively using the magnetic resonance observation of cartilage repair tissue (MOCART) score. All patients had postoperative MRI performed at the 2-year postoperative visit, and quantitative T2 mapping relaxation time values were assessed in a subset of the cBMA/BMS group. RESULTS The mean FAOS and SF-12 PCS scores improved significantly pre- to post-operatively (P < .01) at a mean follow-up of 48.3 months (range, 34 to 82 months) for the cBMA/BMS group and 77.3 months (range, 46 to 100 months) for the BMS-alone group. The MOCART score in the cBMA/BMS group was significantly higher than that in the BMS-alone group (P = .023). Superficial and deep T2 relaxation values in cBMA/BMS patients were higher in repair tissue compared with measurements in adjacent native articular cartilage (P = .030 and P < .001, respectively). CONCLUSIONS BMS is an effective treatment strategy for treatment of OCLs of the talus and results in good medium-term functional outcomes. Arthroscopic BMS with cBMA also results in similar functional outcomes and improved border repair tissue integration, with less evidence of fissuring and fibrillation on MRI.

Posterior Hindfoot Arthroscopy A Review

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.

The Biology of Ewing Sarcoma

Objective. The goal of this study was to review the current literature on the biology of Ewings sarcoma, including current treatments and the means by which an understanding of biological mechanisms could impact future treatments. Methods. A search of PubMed and The Cochrane Collaboration was performed. Both preclinical and clinical evidence was considered, but specific case reports were not. Primary research articles and reviews were analyzed with an emphasis on recent publications. Results. Ewing sarcoma is associated with specific chromosomal translocations and the resulting transcripts/proteins. Knowledge of the biology of Ewing sarcoma has been growing but has yet to significantly impact or produce new treatments. Localized cases have seen improvements in survival rates, but the same cannot be said of metastatic and recurrent cases. Standard surgical, radiation, and chemotherapy treatments are reaching their efficacy limits. Conclusion. Improving prognosis likely lies in advancing biomarkers and early diagnosis, determining a cell(s) of origin, and developing effective molecular therapeutics and antiangiogenic agents. Preclinical evidence suggests the utility of molecular therapies for Ewing sarcoma. Early clinical results also reveal potential for novel treatments but require further development and evaluation before widespread use can be advocated.

Investigating the Relationship Between Ankle Arthrodesis and Adjacent-Joint Arthritis in the Hindfoot. A Systematic Review.

BACKGROUND Ankle arthrodesis traditionally has been regarded as the treatment of choice for many patients with end-stage ankle arthritis. However, a major reported risk of ankle arthrodesis is adjacent-joint degeneration. There are conflicting views in the literature as to the causative link between ankle arthrodesis and progression to adjacent-joint arthritis. Recent studies have challenged the causative link between arthrodesis and adjacent-joint arthritis, purporting that preexisting adjacent-joint arthritis is present in many patients. The aim of the present study was to systematically review the available literature to determine if there is sufficient evidence to support either hypothesis. METHODS A literature search of the EMBASE and PubMed/MEDLINE databases (1974 to present) was performed. A total of twenty-four studies were included for review. The studies were reviewed, and the relevant information was extracted, including research methodology, postoperative outcomes in the adjacent joints of the foot, and whether pre-arthrodesis radiographs and medical records were available for analysis. RESULTS The twenty-four manuscripts included eighteen clinical studies, five biomechanical studies, and one gait-analysis study. The majority of biomechanical studies showed altered biomechanics in the fused ankle; however, there was no clear consensus as to whether these findings were causes of adjacent-joint arthritis. In studies assessing clinical outcomes, the reported prevalence of subtalar joint arthritis ranged from 24% to 100% and the prevalence of talonavicular and calcaneocuboid arthritis ranged from 18% to 77%. Correlation between imaging findings of arthritis in adjacent joints and patient symptoms was not established in a number of the clinical studies reviewed. CONCLUSIONS There is no true consensus in the literature as to the effects of ankle arthrodesis on biomechanics or whether ankle arthrodesis leads to adjacent-joint arthritis. Similarly, a correlation between postoperative imaging findings and clinical presentation in this cohort of patients has not been conclusively demonstrated.