Lower Limb Hamstring Strains Dr. Peter Friis MB BS FACSP Sports Physician 16% missed games AFL 6-15% injury in rugby 30% recurrent What are Hamstrings? 1
Risk Factors Modifiable Warm up Fatigue Strength Flexibility L/Spine Pelvic tilt Tec hni que Sport Non Age Previous strain Indigenous Hamstring Strains Biceps femoris more prone to injury due to insertion and innervation. Biceps stretches more than the other two hamstring muscles. Hamstrings act as agonists of the ACL and acting eccentrically are more prone. Hamstrings cross two joints, rapid switching is a likely factor Pathological muscle contraction The hamstrings are seen to work during late swing phase (presumably to decelerate the extending shank) During stance phase (presumably stabilizing the knee and contributing to horizontal force production during propulsion) of gait. Previously injured muscle The knee flexion angle at which peak concentric torque occurs has been found to increase in previously injured limbs. This finding suggests that torque production at longer muscle lengths may be compromised. strength deficits, particularly at longer muscle lengths, likely increase re-injury risk. Lateral hamstrings work equally hard during swing and stance phase However the medial hamstrings are effectively rested a little during every stance phase. A substantial reduction in biceps femoris long head volume has been found in >50% of individuals with a prior injury despite having returned to athletic competition 2
Changes in the relative amount of connective tissue may also impede recovery Many athletes are likely to be returning to sports with residual atrophy of the biceps femoris (BF) long head. Scar tissue adjacent to the site of original injury has been observed as early as 6 weeks and as late as 23 months after injury. Sanfilippo JL, Silder A, Sherry MA, Tuite MJ, Heiderscheit BC. Hamstring strength and morphology progression after return to sport from injury. Med Sci Sports Exerc. 2013;45:448e454..investigated hamstring morphology at the time of return to sports and 6 months later, and showed that muscle volume decreased 4-5% in this time interval. And.. after 6 months of return to sport, the isokinetic knee flexion strength of the injured and uninjured limbs was the same What is the role of isokinetic strength assessment in identifying hamstring muscle strain injury risk in sport? MRI Grading and Prognosis questionable value in hamstring injury risk assessment in practice. HamSling? used to measure isometric knee flexor strength in supine at 0, 45 and 90 hip/knee flexion Best prognostic indicator is a normal scan.. 3
Knee flexor muscle use during hip extension and the Nordic hamstring exercise: An fmri study Knee flexors are activated non-uniformly during different strengthening exercises. Hip extension exercises more selectively activate ST and SM. NHE preferentially activates the ST and G muscles. BFlh was the least activated muscle during the NHE BFsh was least activated during hip extension. Hamstring Assessment Askling L Exercises Rehabilitation and Functional Tests 4
Prevention wrap-around phenomenon Gluteals Eccentric training Loads Technique Physio During SLR, SN experiences an average of increased strain of 26%. Long stride walking: ischiofemoral space. Piriformis stretch test. 5
Quads Strain 6
Physical examination should record degrees of knee flexion on both legs, firmness rating from 5 to 15 of injured muscle, and circumference of thigh at suprapatelllarborder in both legs. The knee can be maintained in 120 of knee flexion with an elastic wrap or an adjustable range-of-motion brace set at 120of flexion. The patient will need to use crutches, and should maintain this position of knee flexion for 24 hours. Nonsteroidal anti-inflammatory drugs (NSAIDs) should be administered for the first 48 to 72 hours only. Cryotherapy is associated with a significantly smaller hematoma between the ruptured myofibril stumps, less inflammation and less tissue necrosis, and a slightly accelerated early regeneration response. Corticosteroids have been shown to slow healing in contusion injuries by delaying the clearance of debris at the site of injury and prolonging the muscle regenerative process and recovery of muscle strength. Quads Strain? Myositis Ossificans The incidence of myositis ossificans (MO) after muscle contusion has been reported to be 9% to 17%. Bull eye lesion Small tendon in rectus femoris Rehab time significantly more The precalcified stage can cause diagnostic probl ems, bec ause MO is not always connected to a recent trauma and can resemble sarcoma Faint periosteal bone formation, occurs within 7 to 14 days, mature bone after 4-6 months. 7
Groin Pain Compartment Syndrome Athletic Pubalgia Multiple co-existing pathologies are often present which commonly include Posterior inguinal canal wall deficiency, Conjoint tendinopathy, Adductor tendinopathy, Osteitis pubis and Peripheral nerve entrapment. 8
The mechanism of injury remains unclear but sports that involve either pivoting on a single leg (e.g. kicking) or a sudden change in direction at speed are most often associated with Athletic Pubalgia. Pubalgia.chronic groin pain that presents with NO obvious hernia, and no clear-cut cause arising from the structures in the pubic region. Non-modifiable risk factors The most prominent risk factor for groin/hip injuries identified across the literature was: player history of a previous injury. Non-modifiable risk factors The second most prominent, non-modifiable risk factor was: Older Age deficits in physical conditioning, scar tissue formation, inadequate rehabilitation, reduced proprioception, altered movement patterns or premature early return to play after the initial injury 9
Modifiable risk factors The most prominent modifiable risk factors were? BM and WHAM Weak hip adductor muscles (WHAM) Decreased hip abduction ROM and total hip rotation ROM early maturing football players have a greater probability of sustaining a groin/hip injury Adductor-to-Abductor strength ratio of less than 80%. 17 times more likely to sustain a groin injury 10
Adductor Squeeze Test Where is the Hip? 11
Don t forget the Hip! Before asking the patient to lie down, examine the hip and knee in the seated position! Hip range of movement Hip range of movement 12
Femoral neck stress fractures Stress Fracture-NOF DO NOT MISS Female 15-30+ Runner, triathlete Vit D, Calcium menstrual Hx Hop pain, IR REFER 13
Stress Fracture Bone health Ca, pill, periods Vit D Biomechanics Program? rest days US/boots/crutches/ bisphosphonates Graded return 6 weeks Stress Fracture - Shaft Thigh pain Same risks Stress Fracture - Shaft Thigh pain Same risks High loads Hang Test.. Osteitis Pubis Uni or bilateral Vague Initially warms up Gradually deteriorates Prolonged rest 14
Tests Tests Squeeze Adductor spasm MRI Bone scan Flamingo view US other pathology Osteitis Pubis Settle pain Address mechanics Graded return Monitored by squeeze Power and pain Lengthy Options are to grumble or resolve 15
If you choose grumble High maintenance physio Persist Range Eccentric strength Core work Straps/shorts Limit load Respond to soreness CT scan of a normal 23 year old female subject show bilaterally open pubic apophyses Pubic apophysitis can occur at any age prior to closure of the related apophyseal growth plate, typically affecting athletes between the ages of 14 and 26 years Adductor Tendinopathy 16
Grading Grade 1 pain before and after training only Grade 2 pain during training but not affecting training Grade 3 pain that is limiting training Grade 4 pain during activities of daily living Labral Tears of the Hip Pain with crossing legs Pain with end ranges of motion Pinching, catching, or grating feeling inside hip Pain with combined flexion, adduction, and internal rotation (knee across chest) Pain with combined flexion, abduction, and external rotation (knee bent and resting out to side) Pain with resisted straight leg raise (raising leg against resistance) Hip Labral Tear Insidious pain, click or catch Point to groin Money Hip quadrant FABER Physio average CSI Surgery scope or osteotomy Femoro- Acetabular Impingement 17
Bursitis 18
Paediatric Thigh and knee can be from hip DO NOT MISS Refer 19