Complex Regional Pain Syndrome (CRPS) is a condition characterized by severe neuropathic pain in a specific body part, accompanied by autonomic dysfunction, trophic changes, and motor/sensory impairments. Despite the presence of these symptoms causing functional limitations, CRPS could not be recognized as a person with a disability in South Korea until 2021.However, from 2021, it has been possible to certify CRPS as a person with a disability. The certification process requires three key criteria: first, a diagnosis according to the International Association for the Study of Pain (IASP) criteria; second, a sufficient treatment period of over two years since onset of CRPS; and third, evidence of joint contracture or muscle atrophy with objective laboratory or imaging test results. Therefore, it is essential to be familiar with these diagnostic and examination criteria, and, when necessary, to certify individuals with CRPS as having a disability.

Cervical radicular pain and referred pain represent two distinct clinical syndromes commonly encountered in the context of cervical spine pathology. Cervical radicular pain is classified as a neuropathic condition, resulting from mechanical compression or chemical irritation of the dorsal root ganglion (DRG) or cervical spinal nerve root. Such irritation induces ectopic discharges in Aβ and C fibers, often mediated by inflammatory cytokines resulting in sharp, electric-like pain radiating into the upper extremity. Notably, this pain does not conform to a classic dermatomal pattern but more closely aligns with the segmental innervation of deep musculoskeletal structures. In contrast, cervical referred pain arises from non-neural deep somatic tissues such as intervertebral discs, zygapophysial joints, or cervical musculature. It is mediated by spinal convergence of somatic afferents onto shared dorsal horn neurons, often compounded by central sensitization and dichotomizing afferent fibers. These mechanisms lead to spatial mislocalization of pain, which is typically experienced as dull, diffuse, and poorly localized, without accompanying neurological deficits. Experimental and clinical studies demonstrate that nerve root compression alone does not provoke pain unless the DRG is involved, whereas stimulation of deep cervical structures can evoke widespread, non-dermatomal pain. Understanding the distinct pathophysiological basis of cervical radicular and referred pain is essential for accurate diagnosis, clinical differentiation and the implementation of mechanism-targeted treatment strategies in patients with neck pain.

Complex regional pain syndrome (CRPS) is a multifactorial chronic pain disorder characterized by disproportionately severe regional pain accompanied by a range of sensory, vasomotor, sudomotor, motor, and trophic abnormalities. Diagnostic clarity has improved with the adoption of the Budapest criteria, which emphasize the distribution of symptoms and signs across four domains, significantly enhancing specificity and sensitivity compared to earlier definitions. However, due to considerable heterogeneity between patients and across the course of the disease, establishing a uniform treatment strategy difficult to achieve. Pharmacologic management remains challenging due to the lack of high-quality randomized controlled trials, the complex pathophysiology of CRPS, and the variability in patient responses. This review synthesizes the latest evidence on diagnostic approaches and pharmacological treatments for CRPS. No single medication has been proven effective for all patients; rather, targeted pharmacotherapy based on individual symptom profiles, combined with interdisciplinary rehabilitation, is considered the most effective therapeutic approach.

Complex regional pain syndrome (CRPS) is characterized by disproportionate pain and various sensorimotor and autonomic symptoms following trauma or surgery. The pathophysiology remains unclear but involves neurogenic inflammation, autonomic dysfunction, and maladaptive central nervous system plasticity. A multimodal and interdisciplinary approach is essential due to the heterogeneous nature of CRPS symptoms and mechanisms. Rehabilitation strategies commonly incorporate patient education, exercise interventions such as range of motion exercises and functional training, sensorimotor interventions including mirror therapy and graded motor imagery, and physiotherapy. Sensorimotor training shows promise in addressing maladaptive neuroplastic changes. Although current evidence is limited by small sample sizes and heterogeneity, meta-analyses suggest beneficial effects on pain and function. Physiotherapy and occupational therapy also play roles in preventing disuse and restoring function, despite mixed evidence regarding their efficacy. Overall, rehabilitation for CRPS demands the integration of multiple intervention methods for optimal outcomes and calls for further well-design, large scale investigation to prove their efficacy.

Extracorporeal shock wave therapy (ESWT) has shown promise in treating musculoskeletal conditions, but its application to muscle lesions remains relatively understudied compared to its use in tendon and joint pathologies. Given that ESWT aims to stimulate tissue regeneration, its potential benefit for muscle injuries is substantial, suggesting a likely expansion of its clinical use in this area. This review explores the existing literature on ESWT for muscle lesions, aiming to identify potential future applications. Specifically, we examine two key areas: the use of ESWT for improving muscle flexibility and its efficacy in promoting muscle damage recovery.

Cervical radicular pain is a common cause of upper extremity symptoms but often presents with atypical patterns that do not align with classic dermatomal or myotomal distributions. This clinical overlap complicates the diagnostic process and requires consideration of various differential diagnoses. This review outlines three important conditions that can mimic cervical radiculopathy: thoracic outlet syndrome (TOS), neuralgic amyotrophy (NA), and peripheral neuropathy involving proximal or distal nerves.NA, or Parsonage-Turner syndrome, is characterized by acute onset of severe shoulder pain followed by muscle weakness, often involving the long thoracic, suprascapular, or anterior interosseous nerves. Diagnosis is primarily clinical, as electrodiagnostic findings may be normal in early stages. TOS, particularly the neurogenic type, presents with diffuse upper extremity pain and paresthesia, with diagnostic challenges due to overlapping symptoms and the predominance of “disputed” forms lacking objective findings. Peripheral neuropathies may present with focal sensory deficits or motor weakness, depending on the involved nerve and location. This review highlights the importance of comprehensive history-taking, physical examination, and appropriate use of electrodiagnostic and imaging studies to distinguish these conditions. Accurate differential diagnosis is crucial to guide appropriate management and improve patient outcomes.

Rotator cuff tears represent a significant cause of shoulder pain, impacting patient quality of life and contributing to substantial socioeconomic burden. Treatment strategies, particularly for small-sized tears, remain a subject of ongoing debate, with considerations including tear size, patient demographics, and functional demands. This review aims to synthesize and critically analyze existing literature to address the clinical question: ‘Is surgical intervention invariably necessary for small-sized rotator cuff tears?’ Specifically, this review will examine the natural history of small-sized rotator cuff tears, evaluate the methodologies and outcomes of both conservative and surgical treatment modalities, and delineate the factors influencing treatment decision-making.Through this comprehensive analysis, the author intends to facilitate the development of more evidence-based and individualized treatment plans for patients presenting with small-sized rotator cuff tears, ultimately optimizing patient outcomes.

The advent of single-cell transcriptomics marked a paradigm shift in biology, enabling in-depth analysis of cellular heterogeneity and molecular mechanisms at a previously unachievable resolution. Single-cell transcriptomics has revealed previously unrecognized subpopulations, rare cell types, transitional states, and molecular signatures. Many of these novel insights have been successfully translated to therapeutic applications. This review examines the brief history and computational strategies involved in the single-cell transcriptomics technique, as well as the applications of single-cell transcriptomics in musculoskeletal regenerative medicine, focusing on recent discoveries in bone, cartilage, muscle, and tendon biology. Key findings include identification of novel progenitor populations, differentiation pathways, and insights into disease mechanisms. We discuss how single-cell transcriptomics is making breakthroughs in therapeutic strategies through improved understanding of regenerative processes and cellular dynamics.

Sialorrhea is a common clinical problem, particularly in patients with neurological disorders, where it can lead to significant physical and psychosocial burdens, as well as serious complications such as aspiration pneumonia. Ultrasound-guided intraglandular botulinum toxin (BTX) injection has emerged as a safe and effective treatment for sialorrhea. This technique targets the parotid and submandibular glands—responsible for the majority of salivary output—using high-resolution ultrasound to improve localization and avoid nearby vascular structures. The injection is typically performed with the patient in a hyperextended neck position and the head rotated contralaterally, using anatomical landmarks such as the tragus, mandibular angle, and chin tip to guide probe placement. A linear transducer and a 22∼25 gauge needle are recommended, with either an in-plane or out-of-plane approach employed based on operator preference and gland accessibility. While bilateral injections of both glands are common, gland selection should be individualized based on salivary physiology and therapeutic goals. The optimal dose varies by age and weight, with most studies suggesting a maximum of 4 U/kg to minimize adverse effects. Reported complications are generally mild, including transient dysphagia and xerostomia, with serious adverse events being rare.Treatment efficacy lasts up to 16 weeks and can be monitored through both caregiver-reported scales and objective methods such as ultrasound-based assessments of gland size and vascular flow. Despite variability in dosing protocols and target gland selection, this technique has shown consistent efficacy and safety across age groups, and is increasingly adopted as a standard intervention for drooling management.

Objective: Primary frozen shoulder causes significant pain and progressively restricts shoulder movements. Diagnosis is made clinically based on patient history and physical examination. Management is mainly non-invasive owing to its self-limiting clinical course. However, clinical practice guidelines for frozen shoulder have not yet been developed in Korea. The developed guidelines aim to provide evidence-based recommendations for the diagnosis and treatment of frozen shoulder. Methods: A guideline development committee reviewed the literature from four databases (PubMed, Embase, Cochrane Library, and KMbase). Using the Population, Intervention, Comparator, and Outcome (PICO) framework, the committee formulated two backgrounds and 16 key questions to address common clinical concerns. Recommendations were made using the Grading of Recommendations, Assessment, Development, and Evaluation framework. Results: Diabetes, thyroid disease, and dyslipidemia significantly increase the risk of developing a frozen shoulder. Although frozen shoulder is often self-limiting, some patients may experience long-term functional disabilities. Ultrasound and magnetic resonance imaging should be used as adjunctive tools alongside clinical diagnosis, and rather than as independent diagnostic methods. Noninvasive approaches, such as medications, physical modalities, exercises, electrical stimulation, and manual therapy, may reduce pain and improve shoulder function. Other noninvasive interventions have limited evidence, and their application should be based on clinical judgment. Intra-articular steroid injections are recommended for treatment, and physiotherapy or hydrodilation with steroid injections can also be beneficial. Conclusion These guidelines provide evidence-based recommendations for diagnosing and treating primary frozen shoulder.