MSK1 Muscle Tissue Architecture & Injury 2024 PDF

MSc Physiotherapy MSK1 PP6007– Lower Quadrant Muscle Injury- Hamstring 02/04/2024 Declan O'Sullivan 1 Lecture Content Epidemiology of MSK related muscle pain Mechanisms of Injury Treatment Return to Play Delayed Onset of Muscle Soreness (not delivered in Lecture but there for reading) 02/04/2024 Dec...

MSc Physiotherapy MSK1 PP6007– Lower Quadrant Muscle Injury- Hamstring 02/04/2024 Declan O'Sullivan 1 Lecture Content Epidemiology of MSK related muscle pain Mechanisms of Injury Treatment Return to Play Delayed Onset of Muscle Soreness (not delivered in Lecture but there for reading) 02/04/2024 Declan O'Sullivan 2 Objectives of this lecture To identify soft tissue injury rates in various sports To understand the difficulties of describing a muscle tear To understand the current hamstring classification systems To understand current thinking around the mechanism of hamstring injury To appreciate the exercise selection criteria for hamstring rehab To understand the return to play decision making process 02/04/2024 Declan O'Sullivan 3 8.6 million sports and recreation related injury episodes was reported, with an age-adjusted rate of 34.1 per 1,000 population. Males (61.3%) Involved strains and sprains (41.4%), fractures (20.0%), and superficial injuries and contusions (19.0%) Frequently injured were lower extremity (42.0%), upper extremity (30.3%), and head and neck (16.4%). 02/04/2024 Declan O'Sullivan 4 Types of Activities 02/04/2024 Declan O'Sullivan 5 Mechanism of Injury & Bodily Location 02/04/2024 Declan O'Sullivan 6 44 studies reported the incidence of injuries in football Overall incidence of injuries in professional male football players was 8.1 injuries/1000 hours of exposure. Paucity of studies reporting incidence rates separately for different muscle groups (eg, gluteus,hamstrings, quadriceps, abductors, adductors, triceps surae), Match injury incidence (36 injuries/1000 hours of exposure) was almost 10 times higher than training injury incidence rate (3.7 injuries/1000 hours of exposure) Sub-analysis aimed at identifying the most injured muscle group was not possible. Lower extremity injuries had the highest incidence rates (6.8 injuries/1000 hours of exposure). The most common types of injuries were muscle/tendon (4.6 injuries/1000 hours of exposure), which were frequently associated with trauma 02/04/2024 Why? Declan O'Sullivan 7 02/04/2024 Declan O'Sullivan 8 Soccer Methodology: Results: -A total of 1614 hamstring injuries were recorded; 22% of players sustained at least one hamstring injury during a season. -36 clubs from 12 European countries were followed between 2001 and 2014. -The overall hamstring injury rate over the 13-year period was 1.20 injuries per 1000 h -Team medical staff recorded individual player exposure and time-loss injuries. -Injuries per 1000 h were compared as a rate ratio (RR) with 95% CI. Injury burden was the number of lay off days per 1000h. -The time-trend analysis showed an annual average 2.3% year on year increase in the total hamstring injury rate over the 13year period Why ? -This increase over time was most pronounced for training injuries—these increased by 4.0% per year -The average hamstring injury burden was 19.7 days per 1000 h (annual average increase 4.1%) 02/04/2024 Declan O'Sullivan 9 Gaelic Games Methodology: -Prospective Observational Study Results: -Similar to soccer Match-play injury rates were 50.4/1000 h of football and 46.5/1000 h of hurling. -16 male Inter county football and hurling teams were tracked over the 2007–2009 seasons. -Muscle was the most frequently injured tissue (football: 38.3% to 45.8%; hurling: 35.5% to 42.2%) -New injury diagnoses and classifications were recorded by the team physiotherapist or doctor onto the National GAA Injury Database. -Hamstring injuries were the single most common injury overall (football: 17.4% to 25%,hurling: 15.7% to 16.5%). -Injury was defined as requiring 24hr time loss from training or match-play. Incidence rate was calculated as injuries/1000 h training and match play. 02/04/2024 Declan O'Sullivan 10 e g A Not 02/04/2024 c fi i c Spe Declan O'Sullivan 11 Rugby Methodolgy: -A two season prospective design was used to study training injuries associated with 502 rugby union players at 11 English Premiership clubs. Results: -The overall incidence of injury was 2.0 per 1000 playerhours, and each injury resulted on average in 24 days lost time. -Team clinicians reported all training injuries on a weekly basis and provided the location, diagnosis, severity, and mechanism of each injury. -Recurrences, which accounted for 19% of injuries, were more severe (35 days) than new injuries (21 days). -Training exposures for individual players were recorded on a weekly basis. -Loss of time from training and match play was used as the definition of an injury. 02/04/2024 -Hamstring Incidence – 30% of all reported injuries What do recurrences tell you as a physiotherapist? Declan O'Sullivan Australian Rules Football Study Design: A narrative review of AFL injuries, football injury epidemiology, biomechanical and physiological attributes of relevant injuries in the 2015 season. Objective: To provide an overview of injuries in Australian rules football, including injury rates, patterns, and mechanisms across all levels of play 02/04/2024 Findings: The overall injury incidence in the 2015 season was 41.7 injuries per club per season, with a prevalence of 156.2 missed games per club per season. Lower limb injuries are most prevalent, with hamstring strains accounting for 19.1 missed games per club per season. Hamstring strains related to the volume of high-speed running required in addition to at times having to collect the ball while running in a position of hip flexion and knee extension exposing the proximal hamstring tendon Declan O'Sullivan 13 02/04/2024 Declan O'Sullivan 14 Muscle Injuries Muscle Strain Delayed Onset of Muscle Pain (DOMS) (Self Directed Learning) Muscle Contusion (Self Directed Learning) (Paper) 02/04/2024 Declan O'Sullivan 15 What is Hamstring muscle strain? Thoughts? 02/04/2024 Declan O'Sullivan 16 What is Hamstring Muscle Strain? “Time to Change the Classification System” Hamilton et al 2015 Muscle strain may be defined as the ratio of muscle length deformation relative to the muscle resting length A limitation to the comprehensive study of muscle injuries has been the lack of uniformity in their categorisation and description. The terms classify and grade do not refer to the same process. Injury ‘classification’ refers specifically to describing or categorising an injury (eg, by its location, mechanism or underlying pathology). By contrast, a ‘grade’ provides an indication of injury severity. 02/04/2024 Declan O'Sullivan 17 Muscle injuries are classified as either being derived from internal forces (Intrinsic risk Factors) or external forces (Extrinsic Risk Factors) Anatomically, it is recognised that the muscle may ‘rupture’ in distinct locations such as ‘where fibres meet the tendon’ (muscle-tendon junction), the ‘body of the muscle’ (intramuscular) or in the tendon (Intra-tendinous) The classification of muscle injuries by the causal mechanism (intrinsic vs extrinsic forces) and the anatomical location of the injury has remained largely unchanged with time to this day. The arrival of modern imaging modalities e.g. MRI / US have sparked renewed interest in achieving a universal muscle injury classification system “What are the consequences for Physiotherapists, Sport Medicine practitioners, radiologists and S&C coaches due to these shortcomings?” 02/04/2024 Declan O'Sullivan 18 What is currently in Place No Imaging 02/04/2024 No Imaging Ultrasound Declan O'Sullivan MRI 19 Functional Unit of Skeletal Muscle 02/04/2024 Declan O'Sullivan 20 Histoarchitectural location of muscle injuries 02/04/2024 Declan O'Sullivan Balius et al 2018 21 Balius et al 02/04/2024 Declan O'Sullivan 22 Muscle Architecture- Hamstring Muscle Group 02/04/2024 Declan O'Sullivan 23 Muscle ArchitectureRectus Femoris 02/04/2024 Declan O'Sullivan 24 Muscle ArchitectureSoleus 02/04/2024 Declan O'Sullivan 25 Injuries are graded 0–4 based on MRI features, with Grades 1–4 including an additional suffix ‘a’, ‘b’ or ‘c’ if the injury is ‘myofascial’, ‘musculo-tendinous’ or ‘intratendinous’. Grade 0a classifies a clinical presentation of focal muscle soreness usually after exercise, although it may also occur during exercise Grade 0b—generalised muscle soreness with normal MRI or MRI characteristic of DOMS Myofascial 02/04/2024 Declan O'Sullivan Musculotendinous Intratendinous 26 Grade 1 Muscle Injury Grade 1 injuries are small injuries (tears) to the muscle. Present with pain during or after activity. ROM at 24 h will usually be normal and although there may be pain strength and initiation of contraction is fine Grade 1a - extend from the fascia and demonstrate high signal change on fat suppressed/STIR axial images within the periphery of the muscle, no greater than 10% into the muscle and with a longitudinal length of less than 5 cm within the muscle (sagittal cut) Grade 1b- are sited within the muscle or, more commonly, at the MTJ. High signal change is evident at this site and extends over a limited area of less than 5 cm and less than 10% 02/04/2024 of the muscle cross-sectional area at its maximal site Declan O'Sullivan Depth 27 Grade 2 Muscle Injury Grade 2 injuries are moderate injuries (tears) to the muscle. Present with pain during activity which necessitates them to stop activity. ROM of the affected limb at 24hrs will usually show some limitation with pain on initiation of contraction 02/04/2024 Declan O'Sullivan 28 Grade 2a (myofascial)- extend from the peripheral fascia into the muscle History of pain during change of direction and decreased manual strength tests In axial view High signal change will extend between 5 and 15 cm into the muscle 02/04/2024 Declan O'Sullivan 29 Grade 2b (Myotendinous)- occur within the muscle or, more commonly, at the MTJ Grade 2c (Intra-tendinous) extend into the tendon but injury within the tendon is evident over a longitudinal length of less than 5 cm and less than 50% of the maximal tendon diameter on axial images 02/04/2024 Declan O'Sullivan 30 Grade 3 Muscle Injury Grade 3 injuries are extensive tears to the muscle. Present with sudden onset pain and athlete may fall to the ground. ROM at 24 h is usually significantly reduced with pain on walking. There is usually obvious weakness in contraction. Grades 3a (myofascial) and 3b (muscular/musculotendinous) will demonstrate MRI features of high signal change patterns of greater than 50% of the muscle cross-sectional area or greater than 15 cm in length. Evidence of architectural fibre disruption which is likely to be greater than 5 cm. Grades 3a and 3b are differentiated by the location extending to the periphery (3a) or being within the muscle/at the MTJ (3b). 02/04/2024 Declan O'Sullivan 31 Grade 3 Muscle Injury Grade 3c (intratendinous) injuries have evidence of injury in the tendon over a longitudinal length of greater than 5 cm or greater than 50% of the tendon’s maximal cross-sectional area. There is no evidence of a complete defect but there may be loss of the usual straight margins and tendon tension suggesting some loss of the tendon integrity Tendon Waviness 02/04/2024 Declan O'Sullivan 32 Grade 4 Muscle Injury Grade 4 injuries are complete tears to either the muscle (grade 4) or tendon (grade 4c). Experience sudden onset pain / POP & significant and immediate limitation to activity. A palpable gap will often be felt. There may be less pain on contraction than with a grade 3 injury 02/04/2024 Declan O'Sullivan 33 British Athletics Muscle Injury Classification System The British Athletics Muscle Injury Classification demonstrated excellent: Munich Consensus -The Interrater Kappa values of 0.88 (95% CI = 0.76-1.00;P < 0.0001). Vs -The intrarater Kappa value for the two reviewers were 0.76 The percentages of agreement were 82% and 72% interrater and intrarater respectively James et al (2015) 02/04/2024 Declan O'Sullivan British Athletic Muscle Injury Classification System 34 Mechanism of Hamstring Injury ? ? 02/04/2024 Declan O'Sullivan 35 Mechanism of Hamstring Injury-(Intrinsic Risk Factors)Characteristics of Muscle Tissue Biarthrodial muscles have greater contraction velocity and greater capacity to change length, but less capacity to withstand tension. They are generally located in superficial compartments eg rectus femoris, biceps femoris, semitendinosus and gastrocnemius muscles – (Active / Passive Insufficiency) Please observe the graphs and interpret their meaning 02/04/2024 Declan O'Sullivan 36 Fibre length is an important determinant of the quantity of contraction possible in a muscle. Since myofibrils generally present oblique distribution within a hamstring muscle belly, they are generally shorter than the total length of the muscle. The majority of hamstring muscle strain-type injuries occur while the athlete is running at maximal or close to maximal speeds (Askling et al 2007). Tension and ROM 02/04/2024 Declan O'Sullivan 37 Sprint Mechanics Pick a limb Identify Swing Phase Identify Initial Contact Can you identify muscle action during this movement? Where is the potential for hamstring or hip flexor injury during this sprint? 02/04/2024 Declan O'Sullivan 38 Purpose: To quantify: 1. the biomechanical load (i.e., musculotendon strain, velocity, force, power, and work) experienced by the hamstring across a full stride cycle during over ground sprinting 2. To compare the biomechanical load across the four hamstring muscles (i.e., SM, ST, BFLH, and BFSH) “How does this paper inform our 02/04/2024 Findings: The biarticular hamstrings undergo a stretch–shortening cycle during sprinting, with the lengthening phase occurring during terminal swing and shortening phase commencing just before foot strike and continuing throughout stance. The biomechanical load on the biarticular hamstring muscles was found to be greatest during terminal swing. At this time in the stride cycle, ST, SM, and BFLH all reached peak muscle tendon strain, produced peak musculotendon force, and performed much negative work When comparing the various hamstring muscles, the following results were found: (i) BFLH had the largest peak musculotendon strain (12.0% increase in length from upright stance position) (ii) ST displayed the greatest musculotendon lengthening rehab?” velocity, (iii) SM produced the highest musculotendon force, absorbed and generated the most musculotendon power, and performed the largest amount of positive and negative Declan O'Sullivan work. 39 Declan O'Sullivan 04/02/2024 40 Purpose: To investigate the loading conditions of the hamstring muscles during maximum-effort over ground running Findings: In late swing, the leg was swinging forward due to its inertia, which causes a large hip flexion muscle torque and a knee-extension muscle torque at the same time. Consequently, the hamstrings were recruited and started to extend the hip and flex the knee joints to counteract these passive effects for the subsequent ground contact – Limb Deceleration approximately 10 times the subjects’ average body weight / SSC GRFs passed anteriorly to the knee and hip joints during the initial stance phase, which generated Peak extension torque at the knee and Peak flexion torque at the hip at the same time As the early stance is a continuation of the late swing, the hamstrings were contracting concentrically after being fully extended. The muscles were suffering from enormous loads caused by 2 different factors (the inertia and the GRFs) throughout this eccentric–concentric transition. 02/04/2024 Declan O'Sullivan 41 Mechanisms of Hamstring Strain- Extrinsic Risk Factors Purpose: To investigate possible relationships between mean session running distances, session ratings of perceived exertion (s-RPE) and HSIs within AFL footballers (2016). 22 hamstring strain injuries were sustained across the 2013 (n=11) and 2014 (n=11) seasons, all of which occurred after the first 13 weeks of each preseason. *the majority of hamstring strain injuries were sustained during match play (14 out of 20) rather than training ?? No significant differences were found in total absolute highspeed running distances between the INJ and UNINJ groups The likelihood of hamstring strain injuries increased (OR=1.96,95% CI 1.54 to 2.51, p