New England Journal of Medicine Publishes the Results of the Trial in Patients with Acute Muscle Injury

Skeletal muscle injuries present a challenge in primary care and sports medicine. This is a fast-growing market with a number of bio-pharma companies developing new treatment to reduce inflammation, to enhance injury healing and reduce a player’s injury time.  The global sports medicine market is projected to reach USD 8.24b by 2022 from USD 5.78 Billion in 2017, at a CAGR of 7.4% during the forecast period. Sports injuries and developments in the field of regenerative medicine are the key factors driving this growth.

Current treatment options for sports injuries, which include rest, nonsteroidal anti-inflammatory drugs and physical therapy are limited and often found ineffective. The results from our collaborative work investigating in the randomized controlled trial involving 50 amateur athletes, were just published in the New England Journal of Medicine (28 Sept, 2017).

We conducted a randomized, controlled trial involving 50 amateur athletes with acute injury of the thigh muscle (in approximately 60% of the patients) or calf muscle (in approximately 40%), as confirmed on ultrasonography and MRI.

Patients (mean age, 34 years) were recruited less than 48 hours after injury and underwent randomization to receive early therapy (2 days after injury) or delayed therapy (9 days after injury) and were followed for 12 months.

The primary outcome was a return to sports, which was defined as the first time point of full participation in sports after being asymptomatic and successful completion of a functional test (a score of ≤1 on the Numeric Pain Rating Scale, which ranges from 0 to 10 with higher scores indicating a greater level of pain).

The results demonstrated that the interval between severe muscle injury and a return to sports was shorter in the early-therapy group than in the delayed-therapy group, with a median interval of 62.5 days (interquartile range, 48.8 to 77.8) and 83.0 days (interquartile range, 64.5 to 97.3), respectively (P=0.01).

This study shows the clinical consequences of protracted immobilization after a recreational sports injury. Starting rehabilitation 2 days after injury rather than waiting for 9 days shortened the interval from injury to pain-free recovery and return to sports by 3 weeks without any significant increase in the risk of reinjury.

Rehabilitation can result in prolonged pain and a delayed return to sports, a finding that emphasizes the importance of regular and controlled mechanical loading early after trauma to large muscles.

Read the full article:

Early versus Delayed Rehabilitation after Acute Muscle Injury

Authors: Bayer ML1, Magnusson SP1, Kjaer M1; Tendon Research Group Bispebjerg.

Collaborators: Hoegberget-Kalisz MOlesen JLSvensson RBBoesen M.

N Engl J Med. 2017 Sep 28;377(13):1300-1301. doi: 10.1056/NEJMc1708134.



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Left: MRI of the knee from a patient with Osteoarthritis / Injury.
Middle and Right: MRI of the hand from a patient with Muscle Pain.
MRI data analyzed with DYNAMIKA Platform to detect and quantify the inflammatory activity in the muscle.