Imaging of muscle injury in the elite athlete

Abstract

Injuries to muscle in the elite athlete are common and may be responsible for prolonged periods of loss of competitive activity. The implications for the athlete and his/her coach and team may be catastrophic if the injury occurs at a critical time in the athlete's diary. Imaging now plays a crucial role in diagnosis, prognostication and management of athletes with muscle injuries. This article discusses the methods available to clinicians and radiologists that are used to assess skeletal muscle injury. The spectrum of muscle injuries sustained in the elite athlete population is both discussed and illustrated.

Figure 1

A 28-year-old male professional footballer with grade I distal hamstring strain. Axial fat-saturated proton density-weighted image through the distal thigh demonstrating oedema within the long head of the biceps femoris muscle centred on the musculotendinous junction (arrow). Note the perifascial fluid surrounding the muscle at the injury site (arrowheads).

Figure 2

A 26-year-old male professional footballer with grade I distal hamstring strain. (a) Axial fat-saturated proton density-weighted image demonstrating high signal at the myofascial surface of the long head of biceps muscle (arrow). (b) Axial B⁰50 diffusion-weighted image and (c) apparent diffusion coefficient mapped axial image obtained at the same level showing high signal within the periphery of the muscle (arrow).

Figure 3

A 33-year-old male professional footballer with a history of previous calf muscle strain. (a) Sagittal T₁ weighted image through the calf demonstrating focal fatty infiltration of the soleus muscle (arrow), which fully suppresses on the fat-suppressed short tau inversion–recovery sagittal image at the same level (b). Without the T₁ image, the low-signal area within the muscle could be misinterpreted as an intramuscular scar.

Figure 4

A 22-year-old cricket professional fast bowler with grade II right latissimus dorsi strain. Extended field of view sonogram demonstrating a tear within the latissimus dorsi muscle (LD) surrounded by haematoma (arrowheads).

Figure 5

A 27-year-old female elite sprinter with grade I thigh strain. Axial sonogram of the rectus femoris muscle with colour Doppler demonstrating increased blood flow within the muscle at the injury site.

Figure 6

A 25-year-old professional footballer with minor thigh contusion. The arrow indicates the direction of impact of the blow. Note the high signal within the vastus lateralis and vastus intermedius muscles in the line of the force vector. Two-muscle involvement is unusual in eccentric load muscle strains and is more consistent with muscle contusion.

Figure 7

A 31-year-old male amateur footballer with intramuscular haematoma. Extended field of view sonogram demonstrating a laceration (arrows) within the posterior aspect of the vastus medialis obliquus (VMO) muscle anterior to the femoral cortex (F).

Figure 8

A 32-year-old male professional footballer with a deep surface thigh haematoma. (a) Coronal and (b) axial short tau inversion–recovery MRI of the anterior thigh demonstrating a large haematoma deep to the vastus intermedius muscle (arrowheads) adjacent to the femoral cortex (F). Note the laceration into the muscle (arrow) and the layering of blood products on the axial image (curved arrow). The player was imaged 2 weeks after the original injury and had completed two full games in the interval between the injury and the MRI scan.

Figure 9

A 27-year-old male elite boxer presenting with pectoralis muscle contusion following punch injury to the chest. Note the generalised reflectivity within the clavicular (CH) and sternocostal (SCH) heads of the pectoralis major muscle.

Figure 10

A 26-year-old male professional footballer with thigh haematoma. (a) Axial sonogram of the anterolateral thigh 2 days following a direct blow to the lateral side. Note the echogenic torn muscle tissue (arrow). (b) Axial sonogram taken 2 weeks later showing filling in of the haematoma.

Figure 11

A 32-year-old male professional footballer with a thigh deep surface haematoma. Axial T₁ weighted MRI of the anterior thigh of the same player taken at the same position and time as the axial short tau inversion–recovery image in Figure 8. Note the faint high-signal margins of the haematoma consistent with subacute early phase blood products (arrowheads).

Figure 12

A 26-year-old male professional footballer with grade I thigh strain. Coronal short tau inversion–recovery image of the anterior thigh demonstrating ganglion-type cystic fluid collections within the anterior rectus femoris muscle (arrow).

Figure 13

A 28-year-old female elite heptathlete with grade I thigh strain. Longitudinal extended field of view image through the rectus femoris muscle demonstrating increased reflectivity centrally within the muscle obscuring the central tendon (arrows).

Figure 14

A 30-year-old male professional footballer with grade II thigh strain. Axial ultrasound image demonstrating increased reflectivity within the rectus femoris (RF) muscle (arrows) centred on the musculotendinous junction (T).

Figure 15

A 24-year-old male professional footballer with grade II hamstring strain. Axial ultrasound image demonstrating fluid (arrows) within the fascial space between the long (LHBF) and short head of biceps (SHBF) muscles and partial stripping of the muscle from the overlying fascia (arrowheads) consistent with a grade II injury.

Figure 16

A 36-year-old female netball player with “tennis leg”. Longitudinal extended field of view sonogram of the calf demonstrating fluid (arrowheads) in the fascial space between medial gastrocnemius (MG) and soleus (S) superficial to the flexor hallucis longus (FHL) muscle.

Figure 17

A 26-year-old male professional footballer with grade III hamstring tear. The refracted hamstring muscle unit (HMU) has separated (arrowheads) from the tendons (arrow) attached to the ischial tuberosity (I).

Figure 18

A 28-year-old male professional footballer with grade I distal hamstring strain. Sagittal short tau inversion–recovery MRI of the thigh. Note the feathery high signal along the muscle fibres (curved arrow) and the small slither of fluid in the epifascial space (arrows).

Figure 19

A 29-year-old male professional footballer with grade II calf strain. Axial short tau inversion–recovery MRI of the calf. Note the separation of the muscle (arrowheads) away from the deep soleus tendon (arrow) and the prominent epifascial fluid on the deep, medial and lateral surfaces of the muscle.

Figure 20

A 29-year-old male professional footballer with grade II calf strain. Coronal fat-saturated proton-density MRI of the calf. There is laxity within the central tendon (arrows) at the epicentre of the muscle injury.

Figure 21

A 38-year-old female footballer with grade III hamstring avulsion. Sagittal T₂ weighted MRI. The hamstring tendons have avulsed (arrow) and the tear gap is filled by heterogeneous signal-intensity haematoma (arrowheads).

Figure 22

A 26-year-old male rugby player with delayed onset muscle soreness. There is ill-defined increased reflectivity (arrows) within the semitendinosis muscle in the posterior thigh.

Figure 23

A 29-year-old male professional footballer with intramuscular scar. Longitudinal extended field of view sonogram of the anterior thigh demonstrating a large scar centrally within the rectus femoris muscle (arrows).

Figure 24

A 27-year-old male professional footballer with acute thigh strain and history of multiple previous thigh strains. (a) Axial short tau inversion–recovery (STIR) MRI demonstrating multiple scars within both thighs (arrows) as well as an acute strain in the right posterior thigh (curved arrow). (b) Sagittal T₁ and (c) sagittal STIR imaging through the right thigh demonstrating focal fatty change adjacent to the right rectus femoris scar which fully suppresses on the STIR images (long arrows).

Figure 25

A 17-year-old male professional footballer with myositis ossificans. Axial CT scan of the left thigh demonstrating a rim of mature peripheral calcification (arrows) within the left adductor muscle compartment consistent with myositis ossificans.

Figure 26

A 25-year-old male rugby player with early myositis ossificans. (a) Longitudinal extended field of view sonogram of the anterior thigh demonstrating a large haematoma (arrows) within the vastus intermedius (VI) deep to rectus femoris (RF). Note the early calcification at the margins of the haematoma (arrowheads). (b) Longitudinal extended field of view sonogram following aspiration of the haematoma so that the gap between the calcification reduces (arrowheads). (c) Sagittal short tau inversion–recovery MRI of the thigh taken 1 week prior to the ultrasound images demonstrates non-specific inflammation within vastus intermedius muscle. Early calcium deposition may be present (curved arrow) and a haematoma is being formed (arrow).