**5. Biceps brachii**

The lesion of the biceps usually involves the tendon portion, more often the long proximal head and to a lesser extent the distal end that inserts into the radial tuberosity. Sometimes biceps muscle tears occur in the belly, especially when the arm remains entangled in ropes during some sports such as skydiving and wakeboarding [25, 26]. Less frequently, the muscle belly can break following direct trauma in a car accident [27].

Complete laceration of the muscle belly of the biceps brachii leads to a loss of muscle strength and unfortunately, few data are available in literature regarding the right choice of treatment. One of the few studies to have compared the effects of a surgical muscle suture with conser‐ vative treatment is the one by Kragh and Basamania in 2002 [25]. In a military base in North Carolina with 25,000 paratroopers, the authors performed nine surgeries in a year and compared the results to those of three patients treated conservatively in previous years. The paratroopers treated surgically achieved significantly better results for strength (measured in supination torque) and appearance. Those who had been treated conservatively had a worse appearance, suffered easy fatigue in repetitive movements of pronation and supination (e.g. use of screwdriver), avoided weight-lifting and in two cases the musculocutaneous nerve was in contact with the skin and not covered by muscle tissue thus easily irritated even by the cuffs on the uniform.

The mechanism of injury is important for the occurrence of lacerations. In parachutists, the entrapment of the arm in the static-line during the launch determines a subcutaneous trans‐ verse lesion and an almost total one of the muscle belly with the proximal and distal stumps retracted; in this case muscle suture is indicated. In the case of water sports such as water skiing or wakeboarders, the mechanism of injury is similar with the entrapment of the arm in a towline that pulls the athlete at great speed. What differs between the two sports is that the lesion usually reported in water sports causes a tearing injury in the proximal-distal direction of the biceps and is not as clear cut as the paratroopers; this sometimes may preclude the muscle suture and require muscle resection [26].

The injury of the muscle belly of the biceps brachii is rare and closely related to particular sports; the indication for surgery is clear as it prevents functional and aesthetic deficits.

Kragh et al. in [25] with regard to the lesions of the biceps brachii recommend the intervention in the case in which the lesion extend more than 95% of the muscle belly.
