Degenerated and healthy cartilage are equally vulnerable to blood-induced damage

Regenerative Medicine for Equine Musculoskeletal Diseases

Simple Summary

Lameness due to musculoskeletal disease is the most common diagnosis in equine veterinary practice. Many of these orthopaedic disorders are chronic problems, for which no clinically satisfactory treatment exists. Thus, high hopes are pinned on regenerative medicine, which aims to replace or regenerate cells, tissues, or organs to restore or establish normal function. Some regenerative medicine therapies have already made their way into equine clinical practice mainly to treat tendon injures, tendinopathies, cartilage injuries and degenerative joint disorders with promising but diverse results. This review summarises the current knowledge of commonly used regenerative medicine treatments and critically discusses their use.

Abstract

Musculoskeletal injuries and chronic degenerative diseases commonly affect both athletic and sedentary horses and can entail the end of their athletic careers. The ensuing repair processes frequently do not yield fully functional regeneration of the injured tissues but biomechanically inferior scar or replacement tissue, causing high reinjury rates, degenerative disease progression and chronic morbidity. Regenerative medicine is an emerging, rapidly evolving branch of translational medicine that aims to replace or regenerate cells, tissues, or organs to restore or establish normal function. It includes tissue engineering but also cell-based and cell-free stimulation of endogenous self-repair mechanisms. Some regenerative medicine therapies have made their way into equine clinical practice mainly to treat tendon injures, tendinopathies, cartilage injuries and degenerative joint disorders with promising results. However, the qualitative and quantitative spatiotemporal requirements for specific bioactive factors to trigger tissue regeneration in the injury response are still unknown, and consequently, therapeutic approaches and treatment results are diverse. To exploit the full potential of this burgeoning field of medicine, further research will be required and is ongoing. This review summarises the current knowledge of commonly used regenerative medicine treatments in equine patients and critically discusses their use.

Platelet Concentrates in Musculoskeletal Medicine

Platelet concentrates (PCs), mostly represented by platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are autologous biological blood-derived products that may combine plasma/platelet-derived bioactive components, together with fibrin-forming protein able to create a natural three-dimensional scaffold. These types of products are safely used in clinical applications due to the autologous-derived source and the minimally invasive application procedure. In this narrative review, we focus on three main topics concerning the use of platelet concentrate for treating musculoskeletal conditions: (a) the different procedures to prepare PCs, (b) the composition of PCs that is related to the type of methodological procedure adopted and (c) the clinical application in musculoskeletal medicine, efficacy and main limits of the different studies.

Synovectomy using Samarium-153 Hydroxyapatite in the Elbows and Ankles of Patients with Hemophilic Arthropathy

This study aimed to evaluate synovectomy with samarium-153 hydroxyapatite (¹⁵³Sm-HA) in synovitis of the elbows and ankles of hemophilic patients. The synovectomy was performed using 185 MBq of ¹⁵³Sm-HA in 166 joints of 82 hemophilic patients, with a mean age of 24.4 years and follow-up of 12 and 42 months, comprising 63 ankles and 84 elbows. Arthropathy was characterized by recurrent joint bleeding. Episodes of hemarthrosis, use of clotting factors, and pain intensity were evaluated before and after treatment. Scintigraphic controls and adverse effects were also considered. Statistical analyses used P ≤ 0,005 as significant. The results pointed that (a) reduction in hemarthrosis was 78% and 68% in elbows and 82% and 72% in ankles; (b) use of clotting factors was 80% and 70% in elbows and 85% and 75% in ankles; (c) pain was 37% and 34% in elbows and 61% and 57% in ankles, after 12 and 42 months, respectively. Three cases of mild reactive synovitis were observed in ankles and four in elbows. There was no joint effusion in any of the cases. In conclusion, the use of ¹⁵³Sm-HA in elbows and ankles was effective, very safe, minimally invasive and showed consistency over time, is another material to utilize in median hemophilic joints.

Differential Interactive Effects of Cartilage Traumatization and Blood Exposure In Vitro and In Vivo

BACKGROUND

Sport injuries of the knee often lead to posttraumatic arthritis. In addition to direct damage of the cartilage, trauma-associated intra-articular bleeding may cause hemarthrosis. Both blood exposure and trauma are known to induce cell death and inflammation and to enhance proteoglycan release in cartilage.

HYPOTHESIS

Blood exposure increases chondrocyte death as well as inflammatory and degenerative processes in traumatized cartilage.

STUDY DESIGN

Controlled laboratory study.

METHODS

Human macroscopically intact osteoarthritic (OA) cartilage explants were impacted by a drop-tower system (0.59 J) and cultivated with or without 10% blood. Interactive effects were studied concerning cell survival, gene expression, and the release of mediators over 24 hours and 96 hours. To evaluate the effects of trauma and hemarthrosis in vivo, a newly established blunt cartilage trauma model in the rabbit was used. Treatment of the knee joints of mature New Zealand White rabbits consisted of the following groups: control (C), arthrotomy (A), arthrotomy with cartilage trauma (AT; 1.0 J), and arthrotomy with cartilage trauma and blood injection (ATH). After 1 and 12 weeks, inflammatory mediators in the synovial fluid and histological changes of the cartilage were determined, and immunohistological staining was performed.

RESULTS

The in vitro studies revealed a significant additional or synergistic effect of blood exposure on trauma-induced chondrocyte death, interleukin (IL)-1β and prostaglandin-E2 (PGE2) release, and matrix metalloproteinase (MMP)/pro-MMP level. Singular arthrotomy in vivo induced a temporary inflammation. Histologically, cartilage trauma caused significant OA changes that were not aggravated by an additional hemarthrosis. Trauma led to a persistent deposition of terminal complement complex (TCC), being enhanced by hemarthrosis. However, trauma-induced formation of osteophytes and arthrotomy-induced elevation of tumor necrosis factor-α release were reduced by hemarthrosis.

CONCLUSION

While blood exposure clearly aggravated trauma-induced OA processes in the in vitro model, a singular blood injection revealed heterogeneous effects in vivo, enhancing TCC deposition but reducing trauma-induced osteophyte formation while the histological score of traumatized cartilage was not further impaired.

CLINICAL RELEVANCE

The results of this study indicate that a singular, limited bleeding event might not exacerbate early trauma-induced cartilage degeneration in joint injuries. An early removal of intra-articular blood may not prevent the final resulting cartilage damage.

The use of 185 MBq and 740 MBq of 153-samarium hydroxyapatite for knee synovectomy in haemophilia

The penetration of beta energy of 153-samarium (¹⁵³Sm) (0.8 MeV) is not only appropriate for synovectomy of median articulations but is possible to improve the radiobiological effect using increased activities. The aim of this study was to assess the effectiveness of 185 MBq and 740 MBq of 153-samarium hydroxyapatite (¹⁵³Sm-HA) in knees of haemophilic patients. Thirty-one patients – 36 knees, 30 males, were divided into two groups without coinjection of corticosteroid: A – 14 patients (17 knees) treated with intra-articular dose of 185 MBq of ¹⁵³Sm-HA, average age 23 years; B – 17 patients (19 knees) with 740 MBq of ¹⁵³Sm-HA, average age 21.3 years. The evaluation before and after 1 year of synovectomy used the following criteria: reduction in the number of haemarthroses and use of the coagulation factor and improvement in articular motility. Adverse-effects occurrence was considered too. Early and late scintigraphic studies were performed after synoviorthesis and no joint immobilization was recommended. The reduction in haemarthrosis and use of coagulation factor were: group 1 – 31.3% and 25%; group 2 – 81.5% and 79% with P < 0.001 respectively; no significant improvement in knees motility was noted for both groups. Four cases of mild reactional synovitis were observed in each group. The scintigraphic control showed homogenous distribution of the radiopharmaceuticals with no articular escape; the material was considered safe by its permanence in the articulation. We have significant improvement in the synovectomy of haemophilic knees with 740 MBq of ¹⁵³Sm-HA; the less penetration of its beta radiation was compensated by the increased biological effect with the higher used activity.

Haemophilia and joint disease: pathophysiology, evaluation, and management

In patients with haemophilia, regular replacement therapy with clotting factor concentrates (prophylaxis) is effective in preventing recurrent bleeding episodes into joints and muscles. However, despite this success, intra-articular and intramuscular bleeding is still a major clinical manifestation of the disease. Bleeding most commonly occurs in the knees, elbows, and ankles, and is often evident from early childhood. The pathogenesis of haemophilic arthropathy is multifactorial, with changes occurring in the synovium, bone, cartilage, and blood vessels. Recurrent joint bleeding causes synovial proliferation and inflammation (haemophilic synovitis) that contribute to end-stage degeneration (haemophilic arthropathy); with pain and limitation of motion severely affecting patients' quality of life. If joint bleeding is not treated adequately, it tends to recur, resulting in a vicious cycle that must be broken to prevent the development of chronic synovitis and degenerative arthritis. Effective prevention and management of haemophilic arthropathy includes the use of early, aggressive prophylaxis with factor replacement therapies, as well as elective procedures, including restorative physical therapy, analgesia, aspiration, synovectomy, and orthopaedic surgery. Optimal treatment of patients with haemophilia requires a multidisciplinary team comprising a haematologist, physiotherapist, orthopaedic practitioner, rehabilitation physician, occupational therapist, psychologist, social workers, and nurses. Journal of Comorbidity 2011;1:51-59.