Where Do Injectable Stem Cell Treatments Apply in Treatment of Muscle, Tendon, and Ligament Injuries?

Stem cell therapy in sports medicine: current applications, challenges and future perspectives

Stem cells have demonstrated significant potential for tissue repair and regeneration, making them a promising therapeutic avenue in sports medicine. This review aims to provide a comprehensive overview of the current state of research on the application of stem cells in sports medicine. We will discuss the types of stem cells used, their mechanisms of action, and the clinical outcomes of stem cell therapy in different sports-related injuries. Furthermore, we will delve into the challenges and ethical considerations associated with stem cell therapy, as well as future directions and potential applications of stem cells in sports medicine.

Nonoperative Treatment of the Biceps-Labral Complex

The long head of the biceps and superior labrum should be evaluated as an interdependent functional unit. A focused patient history and physical examination including multiple provocative tests should be performed alongside advanced imaging studies to obtain an accurate diagnosis. Nonoperative treatment modalities including nonsteroidal anti-inflammatory drugs, glucocorticoid injections, and a standardized physical therapy regimen should be exhausted before operative intervention. Significant improvements in pain, functional outcomes, and quality of life are achieved in patients treated nonoperatively. Although these outcomes are less consistent for overhead athletes, return to play and performance metrics seem comparable to those who undergo surgery.

Nonsurgical Management of Ulnar Collateral Ligament Injuries

Ulnar collateral ligament (UCL) injuries are a common source of pain and disability in the overhead athlete and often result in notable loss of time from competition. Over the past 10 to 15 years, the prevalence of UCL injury and reconstruction has undergone a dramatic increase, making it imperative to determine which patients may benefit from a nonsurgical regimen. Nonsurgical treatment involves a multidisciplinary approach of rehabilitation with tailored physical therapy programs and, in certain cases, biologic adjuncts. Physical therapy protocols should focus on strengthening the periscapular muscles, rotator cuff, core musculature, and flexor pronator mass to help stabilize the injured elbow and prevent injury recurrence before the initiation of a progressive throwing program. The implementation of injury prevention programs has shifted the focus from just the elbow and have included the shoulder, legs, and core in an effort to help decrease the stress on the upper extremity. In addition, biologic therapies such as platelet-rich therapy are promising modalities to augment the conservative treatment of UCL injuries but remain under investigation. The purpose of this study is to review available strategies and outcomes for conservatively treating UCL injuries.

Differing efficacies of autologous platelet-rich plasma treatment in reducing pain following rotator-cuff injury in a single patient

Rotator-cuff tears (RCTs) are typically associated with chronic pain. The most common treatment for reducing pain is the injection of cortisone into the injury site. An alternative and increasingly used technique is the injection of autologous platelet-rich plasma (PRP). A limitation of cortisone is its pain relief is short-lived, while PRP has the limitation of providing pain relief to only about 50% of patients, making its efficacy questioned, although when it is effective, its efficacy is longer than cortisone. Little is known about what accounts for these limitations. This paper presents results from a patient with RCTs causing excruciating pain who received an injection of PRP into that shoulder resulting in complete pain elimination that was ongoing at 2 years and 2 months. When 7-month severe posttrauma pain associated with the RCT developed in the contralateral shoulder, PRP prepared the same way and injected by the same person who performed the first injection provided no pain relief. However, a subsequent single cortisone injection resulted in complete pain elimination, which was ongoing at >15 months. These observations indicate that PRP can have inconsistent effects in reducing pain, not only between patients but also within the same patient. Further, although the pain relief induced by cortisone is normally not long-lasting, when given following a PRP injection, it can induce complete pain relief lasting >15 months. This paper discusses possible reasons for the variability in PRP efficacy on pain relief and addresses the possibility that when administered together, PRP and cortisone may act in a complementary manner, leading to significantly greater and longer-lasting pain relief.

Nonoperative treatment of five common shoulder injuries: A critical analysis

Economic pressure highlights the critical need for appropriate diagnosis and treatment of various shoulder pathologies since under-diagnosis and under-treatment can result in increased costs to society in the form of disability and lost production. On the other hand, aggressive over-treatment can further inflate already burgeoning health-care costs and potentially harm the patient. Therefore, it is crucial to distinguish the indications between operative and nonoperative management, especially in common shoulder pathologies such as rotator cuff tears, anterior shoulder instability, biceps tendinitis, lesions to the acromioclavicular joint, and proximal humeral fractures. As a result, a detailed analysis of individual risk factors for potential failures should be performed and treatment should be based on individualized care with consideration given to each patient’s particular injury pattern, functional demands, and long-term goals.

No evidence for the use of stem cell therapy for tendon disorders: a systematic review

INTRODUCTION

Stem cells have emerged as a new treatment option for tendon disorders. We systematically reviewed the current evidence for stem cell therapy in tendon disorders.

METHODS

Randomised and non-randomised controlled trials, cohort studies and case series with a minimum of 5 cases were searched in MEDLINE, CENTRAL, EMBASE, CINAHL, PEDro and SPORTDiscus. In addition, we searched grey literature databases and trial registers. Only human studies were included and no time or language restrictions were applied to our search. All references of included trials were checked for possibly eligible trials. Risk of bias assessment was performed using the Cochrane risk of bias tool for controlled trials and the Newcastle-Ottawa scale for case series. Levels of evidence were assigned according to the Oxford levels of evidence.

RESULTS

4 published and three unpublished/pending trials were found with a total of 79 patients. No unpublished data were available. Two trials evaluated bone marrow-derived stem cells in rotator cuff repair surgery and found lower retear rates compared with historical controls or the literature. One trial used allogenic adipose-derived stem cells to treat lateral epicondylar tendinopathy. Improved Mayo Elbow Performance Index, Visual Analogue Pain scale and ultrasound findings after 1-year follow-up compared with baseline were found. Bone marrow-derived stem cell-treated patellar tendinopathy showed improved International Knee Documentation Committee, Knee injury and Osteoarthritis Outcome Score subscales and Tegner scores after 5-year follow-up. One trial reported adverse events and found them to be mild (eg, swelling, effusion). All trials were at high risk of bias and only level 4 evidence was available.

CONCLUSIONS

No evidence (level 4) was found for the therapeutic use of stem cells for tendon disorders. The use of stem cell therapy for tendon disorders in clinical practice is currently not advised.

Ethical considerations in stem cell research on neurologic and orthopedic conditions

The range and gravity of ethical considerations in stem cell research are remarkable and, quite possibly, unprecedented. From the point of securing stem cells for implantation, through the translational and first-in-humans process, and then proceeding through clinical trials culminating in product or service line launch, the entire research trajectory is replete with risk, uncertainty, and problems overweighing foreseeable harms against hoped-for benefits. This article offers an overview of some of the most salient ethical challenges of stem cell research, including ones involving moral status, the intersection of research risks and informed consent processes, methodologic considerations in early phase 1 trials, the temptation to exaggerate the benefits of research discoveries, managing conflicts of interest, and the ethical obligation to conduct various monitoring practices throughout a trial, which could last years. The article will conclude with a glimpse into the future of these technologies wherein the need for ethical scrutiny will likely not diminish.