Three muscles make up the hamstring complex: the biceps femoris, semitendinosus and semimembranosus. The hamstring crosses both the hip and knee joints, allowing the muscle to flex the knee and extend the hip. Because the hamstring crosses both the hip and knee joints it places it at increased risk.
Hamstring muscle strains or tears are common, and often occur with sport and rapid movements. The hamstring slows knee extension when running or sprinting, with the greatest strain on the hamstring occurring during the swing phase of gait as the muscle elongates. Contracting the muscle at this stage, such as with rapid acceleration and deceleration, can strain the hamstring resulting in tearing of the muscle or tendon.
Tendinitis occurs when the hamstring tendon becomes inflamed, usually as a result of overuse or misuse. It can affect any of the three hamstring muscles, either at the top of the thigh (proximal) or at the back of the knee (distal). This repetitive stress causes inflammation and irritation of the tendon muscle fibers which can lead to small microscopic tears overtime.
Patients with a hamstring tear may present with sharp, stabbing pain that worsens with activity. In some cases a “pop” may be felt or heard at time of injury. Swelling or bruising around the injured area may also be present.
Patients with hamstring tendinitis often present with more gradual aching pain that can be accompanied by stiffness. Pain may be felt in the back of the thigh, knee or deep into the buttocks and worsen with prolonged sitting or running activities.
Diagnosis is based on detailed history, physical examination, and imaging, which are crucial for a correct diagnosis and proper management. During the physical examination, a series of provocative tests may be utilized to further determine presence of injury.
Advanced imaging may be required to confirm diagnosis and determine injury severity. Both magnetic resonance imaging (MRI) and Ultrasound effectively identify and assess hamstring injuries, although MRI has been shown to be more accurate than ultrasound for evaluation of deeper muscle injuries (Chu et al, 2017).
Eccentric strengthening has shown promises in treating tendinopathy, but no randomized controlled trials have specifically looked at eccentric programs for hamstring tendinopathy.
Shockwave therapy may be used as an adjunctive therapy for chronic hamstring tendinopathies. Shockwave therapy initiates the body’s natural healing process with the aim of reduction in pain and increase in function. Learn more about shockwave therapy here.
Historically, steroids have been used in the treatment of tendon pain. Typically steroids will provide a short-term benefit, and for some patients this window of pain relief allows them to rehab the tendon and the pain resolves. Repeated injections may weaken the tendon tissue over time, however.
Platelet rich plasma (PRP) is a minimally invasive non-surgical treatment that promotes healing without surgery using a concentration of a patient's own platelets and growth factors injected into the injured area to stimulate healing. PRP has shown promising results in the literature, specifically in chronic (patients with >3 months of pain) hamstring injuries, although more research is needed as the use of PRP in orthopedics continues (Fader, et al, 2015)
Surgical intervention for partial proximal hamstring tears are not as well studied. However, surgical treatment is recommended for patients with either a 2 tendon tear, avulsion tear where the tendon is pulled greater than >2 cm from the bone or those with complete 3 tendon tears (Moatshe et al, 2016). Surgical intervention for complete injuries have shown good to excellent results, but include risk of infection, nerve damage, deep vein thrombosis (DVT), wound-related complications and prolonged rehabilitation.
With cases of proximal hamstring tendinopathy, surgical treatment may become an option for patients with chronic symptoms that do not respond to conservative treatment (Costa et al, 2016).
Chu SK, Rho ME. Hamstring Injuries in the Athlete: Diagnosis, Treatment, and Return to Play. Curr Sports Med Rep. 2016 May-Jun;15(3):184-90. doi: 10.1249/JSR.0000000000000264. PMID: 27172083; PMCID: PMC5003616.
Costa LP, Barros AAG, Vassalo CC, Sonnery-Cottet B, Barbosa VAK, Temponi EF. A New Technique for Surgical Treatment of Proximal Hamstring Tendinopathy in a Triathlon Athlete. J Orthop Case Rep. 2016 Nov-Dec;6(5):69-72. doi: 10.13107/jocr.2250-0685.638. PMID: 28507970; PMCID: PMC5404168.
Fader RR, Mitchell JJ, Traub S, Nichols R, Roper M, Mei Dan O, McCarty EC. Platelet-rich plasma treatment improves outcomes for chronic proximal hamstring injuries in an athletic population. Muscles Ligaments Tendons J. 2015 Feb 5;4(4):461-6. PMID: 25767784; PMCID: PMC4327356.
Moatshe G, Chahla J, Vap AR, Ferrari M, Sanchez G, Mitchell JJ, LaPrade RF. Repair of Proximal Hamstring Tears: A Surgical Technique. Arthrosc Tech. 2017 Mar 13;6(2):e311-e317. doi: 10.1016/j.eats.2016.10.004. PMID: 28580247; PMCID: PMC5442402.