Angiogenesis and Tissue Repair Depend on Platelet Dosing and Bioformulation Strategies Following Orthobiological Platelet-Rich Plasma Procedures: A Narrative Review.

Angiogenesis is the formation of new blood vessel from existing vessels and is a critical first step in tissue repair following chronic disturbances in healing and degenerative tissues. Chronic pathoanatomic tissues are characterized by a high number of inflammatory cells; an overexpression of inflammatory mediators; such as tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1); the presence of mast cells, T cells, reactive oxygen species, and matrix metalloproteinases; and a decreased angiogenic capacity. Multiple studies have demonstrated that autologous orthobiological cellular preparations (e.g., platelet-rich plasma (PRP)) improve tissue repair and regenerate tissues. There are many PRP devices on the market. Unfortunately, they differ greatly in platelet numbers, cellular composition, and bioformulation. PRP is a platelet concentrate consisting of a high concentration of platelets, with or without certain leukocytes, platelet-derived growth factors (PGFs), cytokines, molecules, and signaling cells. Several PRP products have immunomodulatory capacities that can influence resident cells in a diseased microenvironment, inducing tissue repair or regeneration. Generally, PRP is a blood-derived product, regardless of its platelet number and bioformulation, and the literature indicates both positive and negative patient treatment outcomes. Strangely, the literature does not designate specific PRP preparation qualifications that can potentially contribute to tissue repair. Moreover, the literature scarcely addresses the impact of platelets and leukocytes in PRP on (neo)angiogenesis, other than a general one-size-fits-all statement that "PRP has angiogenic capabilities". Here, we review the cellular composition of all PRP constituents, including leukocytes, and describe the importance of platelet dosing and bioformulation strategies in orthobiological applications to initiate angiogenic pathways that re-establish microvasculature networks, facilitating the supply of oxygen and nutrients to impaired tissues.

First MTP joint instability - Expanding the concept of "Turf-toe" injuries.

BACKGROUND: Although the classic definition of the Turf-toe injury refers to a very specific clinical and pathological picture, we think that the concept can be broadened to encompass a wide variety of traumatic lesions of the first metatarsophalangeal joint (MTP1). These are lesions typically difficult to diagnose, with a large variation of outcomes and a potential to impair patients' functional performance on a definitive and perennial basis. The objective of this study is to present the result obtained by treating 24 cases of traumatic injuries to the MTP1 joint in a midterm follow-up time. METHODS: In the period from 1999 to 2016, 24 patients were treated with MTP1 joint instability - "Expanded Turf-toe" - diagnosis. All patients were performing sports activities when they were injured: soccer (33%); martial arts (17%); running (13%); tennis (8%); olympic gymnastics (8%) and others (basketball, slalom, motorcycling, surfing, and ballet) (21%). Injuries were classified as Grade I (2 patients - 8%), Grade II (8 patients - 33%) and Grade III (14 patients - 59%) lesions. All patients with grades I and II were treated conservatively whereas those classified as grade III were treated surgically. RESULTS: After an average follow-up of 4.5 years we observed an improvement in the AOFAS hallux score from 42 to 82 points after treatment (p<0.001). The most frequent cause was axial load with various direction of stress at the first MTP. The mechanism of lesion varied among extension with hallux varism (42%), pure hyperextension (25%), extension with hallux valgism (21%), pure hyperflexion (8%) and hyperflexion with hallux valgism (4%). A separate analysis of each group showed a significant improvement in AOFAS Hallux scores after treatment: 51-84 (p<0.001) and 36-81 (p<0.001) for conservative and surgical groups, respectively. Four patients with GIII injuries (29%) and two with GII injuries (20%) did not resume their previous activities. Although pre-treatment AOFAS hallux scores were significantly different between groups, post-treatment scores were similar (p=0.615). CONCLUSIONS: Turf-toe is a serious injury that may prevent a high percentage of patients from resuming their previous physical activities. Mechanism of lesion might be varied generating a wide range of lesions that fit into the expanded concept of the Turf-toe injury. Both forms of treatment lead to satisfactory results if well conducted. The correct identification, classification, and grading of first metatarsophalangeal joint (MTP) instability helps in decision making and selection of the adequate treatment. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Metal artifact reduction MRI of total ankle arthroplasty implants.

OBJECTIVES: To assess high-bandwidth and compressed sensing-(CS)-SEMAC turbo spin echo (TSE) techniques for metal artifact reduction MRI of total ankle arthroplasty (TAA) implants. METHODS: Following institutional approval and consent, 40 subjects with TAA implants underwent 1.5-T MRI prospectively. Evaluations included bone-implant interfaces, anatomical structures, abnormal findings and differential diagnoses before and after MRI. AUCs of P-P plots were used to determine superiority. Statistical differences were evaluated with McNemar and chi-square tests. P-values ≤ 0.05 were considered significant. RESULTS: CS-SEMAC TSE was superior to high-bandwidth TSE in showing the bone-implant interfaces (AUC=0.917), periprosthetic bone, tendons and joint capsule (AUC=0.337-0.766), bone marrow oedema (43 % difference, p=0.041), interface osteolysis (63 %, p=0.015), tendinopathy (62 %, p=0.062), periprosthetic fractures (60 %, p=0.250), synovitis (43 %, p=0.250), as well as reader confidence for bone marrow oedema (p=<0.001), fracture (p=0.001), interface osteolysis (p=0.003), synovitis (p=0.027) and tendinopathy (p=0.034). The number of differential diagnoses in symptomatic subjects after the MRI with CS-SEMAC decreased from 3 (1-4) to 1 (1-2) (p<0.001). CONCLUSIONS: MRI of TAA implants with CS-SEMAC improves the diagnosis of interface osteolysis, periprosthetic bone marrow oedema, fractures and tendinopathy when compared to high-BW TSE, and has a positive effect on patient management. KEY POINTS: • High-bandwidth TSE and compressed sensing SEMAC improve MRI of ankle arthroplasty implants. • Compressed sensing SEMAC improves bone-implant interfaces, periprosthetic bone, tendons and joint capsule visibility. • Compressed sensing SEMAC improves the diagnosis of osteolysis, tendinopathy, fractures and synovitis. • MRI decreases the number of clinical differential diagnoses of painful ankle arthroplasty implants.

Fluoroquinolones and the Risk of Achilles Tendon Disorders: Update on a Neglected Complication.

OBJECTIVE: To evaluate the current evidence and to identify associated risk factors that increase the incidence of this complication. Fluoroquinolone (FQ) has been considered the first-line therapy for uncomplicated urinary infections. FQ has been associated with Achilles tendon disorders, especially during the first month of treatment. METHODS: Data sources searched included PubMed, MEDLINE, and Scopus from January 1988 to June 2017. RESULTS: A total of 79 articles were used, with ciprofloxacin representing the most common drug. CONCLUSION: We found that male gender, advanced age, normal body mass index, chronic renal failure, and concurrent use of corticosteroids increase the risk of Achilles tendon disorders.