09/10/2025
📃Muscle Injury: Pathophysiology, Diagnosis, and Treatment
📚 Introduction
🏋️ Muscle injuries are the most frequent cause of physical disability in sports practice
📊 It is estimated that between 30 and 50% of all sports-associated injuries are caused by soft tissue injuries
🧠 Knowledge of some basic principles of skeletal muscle regeneration and repair mechanisms can help prevent imminent dangers and accelerate the return to sport
>>>
🤔 Mechanisms of Injury
⚡ The cause of muscle injury can be considered indirect or direct
🚫 Indirect injury is related to lack of contact, which may be of functional cause (mechanical overload or neurological injury) or structural (partial or complete muscle rupture)
🤕 Direct injury occurs at the contact site, which may cause a laceration or contusion
📉 More than 90% of all sports-related injuries are bruises or stretches
✂️ Muscle lacerations are the least frequent injuries in sports
>>>>
📊 Classification
📌 Classically, systems describe muscle injury at 3 different levels: mild, moderate, and severe (or grade I, II, and III) from imaging evaluation or clinical aspects
1️⃣ Grade I lesions: edema and discomfort
2️⃣ Grade II lesions: loss of function, gaps, and possible ecchymosis
3️⃣ Grade III lesions: complete rupture, severe pain, and extensive hematoma
📖 The classification proposed by Mueller-Wohlfarht et al. (Munich Consensus) and Mafulli et al. also consider etiological aspects: direct (contusion or laceration) and indirect (functional or structural)
📍 The system described by Po***ck et al. (British athletics muscle injury classification) uses the anatomical location and extension of the lesion
🔄 The classification by Valle et al. seeks to group four characteristics: mechanism of injury (M), location (L), degree of injury (G), and number of re-injuries (R)
>>>
🔬 Pathophysiology (Healing Phases)
🔄 Skeletal muscle healing follows a constant order, with three identified phases: destruction, repair, and remodeling
🩸 Phase 1: Destruction – rupture and subsequent necrosis of myofibrils, hematoma formation, and proliferation of inflammatory cells
🔧 Phase 2: Repair and Remodeling – phagocytosis of necrotic tissue, regeneration of myofibrils, connective scar tissue production, vascular neoformation, and neural growth
🔁 Phase 3: Remodeling – maturation of regenerated myofibrils, contraction and reorganization of scar tissue, and recovery of muscle functional capacity
🌱 The regenerative capacity of skeletal muscle is guaranteed by an intrinsic mechanism involving satellite cells
💉 Restoration of vascular supply is the first sign of regeneration and a prerequisite for recovery
>>>>
🩺 Diagnosis
📖 Begins with a detailed clinical history of the trauma followed by a physical examination
🖥️ Ultrasound (US) is traditionally considered the method of choice for initial evaluation; it is inexpensive, accessible, and allows dynamic evaluation, but is examiner-dependent
🎥 Magnetic Resonance Imaging (MRI) allows detailed evaluation of muscle morphology, generating multi-planar, high-resolution soft tissue images, and is used by many authors for classification
🌡️ Infrared medical thermography enables noninvasive assessment of body temperature, detecting physiological changes related to increased risk of muscle injuries
>>>>>
🩹 Treatment
🛡️ Initial phase: Protection, Rest, Optimal Use of the Affected Limb (POLICE protocol), and Cryotherapy
⏳ A short immobilization period with firm or similar adhesive bandage is recommended
❄️ Ice application and compression in shifts of 15 to 20 minutes, repeated every 30 to 60 minutes, decreases intramuscular temperature and blood flow
💊 Nonsteroidal anti-inflammatory drugs (NSAIDs): short-term use in early stages may decrease inflammatory reaction without side effects on healing, but chronic use may be harmful
⚠️ Glucocorticoids: reported delays in hematoma elimination, necrotic tissue removal, regeneration, and reduction of biomechanical strength
🏋️ Post-acute phase: Isometric, isotonic, and isokinetic training, initiated painlessly and gradually
🔥 Local application of heat or "contrast therapy", accompanied by careful passive and active stretching, is valuable
🛠️ Surgical treatment: precise indications include large intramuscular hematomas, complete ruptures (grade III) with little associated agonist musculature, and partial lesions where more than half of the muscle is ruptured
🧬 New perspectives: therapeutic use of growth factors and gene therapy, and application of stem cells are promising, but need greater scientific validation
>>>>
🦵 Specific Muscle Injuries
🦵 Quadriceps muscle injury: more frequent in individuals >40 years old, often due to forced eccentric contraction during a fall. Complete ruptures require early surgical treatment for better functional results
🏃 Hamstring muscles injury: the most common lesion in athletes, often neglected in the acute phase. MRI is valuable for differentiation and planning
👉 Adductor muscle injury: common in athletes requiring repetitive kicks, starts, or changes of direction, often due to imbalance between adductor musculature and abdominal wall. Initial treatment is conservative, but acute ruptures may require surgical repair
👉 Gastrocnemius muscles injury: prone to injury because it crosses two joints; medial head is more commonly injured. Term "tennis leg" describes calf pain and injury. Most lesions are treated conservatively
💪 Pectoral muscle injury: more common due to increased weightlifting practice, typically indirect injury during eccentric phase. Loss of upper limb adduction strength leads to surgical treatment need
🖐️ Distal lesion of the brachial biceps muscle: uncommon, mainly in the dominant limb of males, mechanism is eccentric contraction during elbow extension. Surgical treatment often involves reinsertion
>>>>
✅ Final Considerations
🧠 Understanding pathophysiological mechanisms is essential for prevention, proper treatment, and rehabilitation
🔄 Decision for return to training can be based on the ability to lengthen the injured muscle as much as the healthy contralateral side, and absence of pain in basic movements
👨⚕️ The final phase of rehabilitation should be carried out under the supervision of a qualified professional
-----------------
⚠️Disclaimer: Sharing a study or a part of it is NOT an endorsement. Please read the original article and evaluate critically.
Link to Article 👇