MUSCLE CONTUSION (CORK) Introduction Muscle contusions are essentially bruises of a muscle. There is a direct blunt crushing injury which disrupts the muscle to a variable degree, depending on the force of the injury. In lay sporting terms, muscle contusion is often referred to as a cork. These injuries are very common in the setting of contact sports. The muscles most commonly involved are those of the quadriceps complex of the anterior compartment of the thigh, because of their major bulk, and their more exposed position in the setting of most contact sports - hence, "corked thigh", is a commonly seen injury pattern of muscle contusion. Any muscle however can of course sustain a contusion type injury. Most contusion injuries heal completely with time, however in more severe cases there can be significant complications and long term recovery periods. Optimal outcomes will be closely related to the quality of initial management. Elite sports people are best managed for their ongoing recovery and rehabilitation under the close supervision of a sports medicine specialist. Anatomy Most significant muscle contusions in contact sports are seen around the anterior thigh, so it is important to understand the anatomy of the anterior compartment of the thigh. Anterior thigh muscles: Sartorius Quadriceps femoris Rectus femoris Vastus lateralis Vastus intermedius (deep to rectus femoris)
Vastus medialis Major vascular structures: Femoral artery Femoral Vein Major nerve structures: Saphenous nerve See Appendix 1 below. Pathology Muscle contusion occurs as a result of a direct blunt crushing injury to the muscle. Most commonly the injury is seen in the anterior thigh. Less commonly it is seen in the calf or the upper arm. Complications Most muscle contusions heal well with time, but occasionally with more severe injuries, more serious complications can arise. These can include: 1. Compartment syndrome: Severe injuries may induce a compartment syndrome, due to swelling from oedema and or bleeding. 2. Myositis ossificans: The more severe a contusion, the greater the risk of the development of Myositis Ossificans. In this condition calcification occurs within the healing hematoma. Symptoms include overnight and morning pain, as well as pain on muscle contraction. It may be possible to feel a hard bump or woody feel within the muscle. Stiffness and loss of knee range of movement are also common.
Suboptimal treatment of a contusion may predispose to the development of myositis ossificans. Calcification associated with myositis ossificans usually ceases after six to seven weeks, at which time the formed bone begins to break down and be reabsorbed by the body. Complete recovery can however take up to 12 months in more severe cases. Little can be done to accelerate the reabsorption process of myositis ossificans and care should be taken in the treatment of the condition to avoid its long term effects. 3. Haemorrhage: Rarely bleeding may be so severe as to require surgical intervention. This is only seen in the context to damage to a major arterial vessel. 4. Neuropraxia. Clinical assessment Always assess for the possibility of a compartment syndrome and any neurovascular compromise in muscle contusion injuries. Muscle contusions are generally graded into 3 types according to the clinical severity of the injury: Grade I, (Mild): For a player experiencing a mild muscle contusion: Ability to play: Will usually be able to continue playing. Pain: May feel some mild soreness after cooling down or on the following day. Tenderness: There will be some tenderness to the injured region. Swelling:
Usually no apparent swelling. Function: Able to walk reasonably freely Range of motion mostly intact The strength of the muscle may be mildly adversely affected. Grade II, (Moderate): For a player experiencing a moderate muscle contusion: Ability to play: This will generally prevent further play. Pain: There will be moderate pain. Tenderness: There will be moderate tenderness to the injured region. Swelling: There may be some mild swelling. Function: Usually an antalgic gait Range of motion will be diminished by up to 50%. Some reduction in muscle strength. Grade III, (Severe): For a player experiencing a severe muscle contusion: Ability to play: This will immediately prevent further play Pain:
There is severe pain at the site. Tenderness: There is severe tenderness at the site. Swelling: There is rapid onset of swelling and obvious bleeding. Function: Usually unable to bear weight. Movement loss will be severe (> 50%). Muscle strength will be greatly diminished. Investigations In most cases, muscle contusions do not require investigation. The need to investigate will depend on: The clinical severity of the injury. The degree of concern regarding a potentially serious complication. The eliteness of the level of sport the patient is involved in. The following may be considered: Blood tests If rhabdomyolysis is suspected from a compartment syndrome: FBE U&Es/ glucose (urgent potassium level) CK. Ultrasound This can assess in particular for any muscular tears or other gross disruptions. It is also useful for vascular flow studies, in cases where compartment syndrome may be causing vascular compromise.
CT scan CT will give a better picture of muscle than ultrasound, but not as good as an MRI. MRI MRI will give the best images for muscle injury. It is rarely indicated unless a very severe injury is suspected or a precise determination of the nature of the injury is required in an elite sports person. Management The basic principles of the initial management of any soft tissue injury are particularly important in cases of muscle contusion. These can be summarized as: RICE and No HARM. RICE aims to minimize any further bleeding and oedema into the muscle The RICE protocol is maintained over the first 48-72 hours: 1. Rest: 2. Ice: Moderate to severe contusions may require the initial use of crutches to ensure complete rest, particularly if full weight bearing on the affected leg is painful. Ice packs are applied for 20 minutes every two hours. 3. Compression: Note that ice should never be directly applied to the skin. This is best achieved with an elastic compression bandage such as Tubigrip. 4. Elevation: Note that crepe bandages are not sufficient as they do not maintain adequate compression. Elevation will help reduce bleeding and oedema. 5. No HARM:
This refers to: No heat, (promotes vasodilation and worsens haemorrhage and oedema). No alcohol, (vasodilates, and worsens haemorrhage and oedema). No running or activity, (worsens haemorrhage and oedema) No massaging, (promotes further bleeding and oedema). 6. Analgesia: Simple oral analgesia is usually sufficient, unless the injury is severe, where titrated opioid may initially be required Options include: 2 For less severe pain use: Paracetamol 1gram orally 4 hourly prn (to a maximum dose of 4 gram per 24 hour period) And/or Ibuprofen 400mg orally 6 hourly prn For more severe pain use: Oxycodone immediate release 5 to 10 mg orally 4 to 6 hourly prn With Paracetamol 1gram orally 4 hourly prn (to a maximum dose of 4 gram per 24 hour period) And/or Ibuprofen 400 mg orally 6 hourly prn Following initial management: Strengthening of the injured muscle should begin two to seven days post-injury, depending upon the severity of the injury. Specific exercise programs are managed by Sports medicine practitioners and physiotherapists
Depending on the nature of the sport, a protective padding may be used for a period of time to dissipate the force of impact from blunt injuries. Recovery periods: The return to sport period from all grades of contusion injury may be significantly reduced with: Good early management practices Initial assessment and ongoing supervision by a sports medicine specialist. As a general rule, with optimal treatment: Grade I injuries: Grade II injuries: Grade III injuries: May expect a return to play in 2-3 weeks. May expect a return to play in 4-6 weeks, (minimum). May expect a return to play in 8 weeks, (minimum).
Appendix 1 Anatomy of the anterior compartment of the thigh; Left: Muscles of the anterior thigh. Above: Transverse section through the mid-level of the left thigh, (Gray's Anatomy, 1918).
References 1. Quadriceps Contusion (cork thigh): A guide to prevention and management; Sports Medicine Australia, July 2010. www.sma.org.au 2. The Acute Pain Management Manual NHMRC, 2011. Dr J. Hayes August 2012