Conflicts of interest
Closed traumatic disruptions of biceps brachii muscle belly are rarely seen. In this paper, we report two rare cases of biceps brachii muscle belly rupture sustained while water-skiing or wakeboarding and discuss the mechanism of injury, management and outcomes after a literature review. A review of published articles revealed only three previously reported cases of water skiing related biceps muscle rupture. It is important to be vigilant of these injuries, given that early recognition and operative intervention with or without direct muscle repair may optimise outcomes.
Rupture of the biceps brachii is well documented, usually involving the tendon of the long head of biceps or biceps insertion on the radius [1,2]. Approximately 90% to 97% of all bicep ruptures involve the proximal tendon, and almost exclusively involve the long head of biceps . Closed traumatic disruptions of biceps brachii muscle belly are rarely seen, with the only large series being reported involving the military parachutists [4–6]. We report two rare cases of biceps brachii muscle belly rupture sustained during water-skiing or wakeboarding and discuss the mechanism of injury, management and outcomes after a literature review.
A 31-year-old right-handed male was referred 3 weeks after a water-skiing accident. He fell when traveling at 100 km/h with the left arm through the handle and the elbow flexed, and the pull of the boat painfully wrenched his elbow straight and the handle of the ski rope snapped (there was no direct strike on the arm). On examination, there was an obvious absence of biceps muscle in the upper arm, a palpable proximal forearm mass and extensive brawny oedema (Fig. 1). The patient demonstrated paraesthesia in the distribution of the lateral cutaneous nerve of the forearm, a decreased active range of motion and 4/5 power of the elbow . Magnetic resonance imaging (MRI) revealed complete rupture of biceps muscle belly at the midpoint level. The distal biceps tendon was intact, with 8-cm retraction of the distal muscle belly into the proximal ventral aspect of the forearm (Fig. 2). The patient underwent operative intervention with a stepped incision over the elbow crease. The distal biceps muscle was found to be nonviable, and hence the dead muscle was debrided with no repair (Fig. 3). Damaged branches of the musculocutaneous nerve were terminalized. At 3-month follow-up, the patient was satisfied with the outcome, having regained full range of motion, near normal power and was back at work as a carpenter. He was not particularly concerned about the contour deformity of his arm as a result of the absence of the biceps muscle.
A 20-year-old right-handed male was seen for surgical opinion regarding the treatment of his left upper limb injury, 10 weeks after a wakeboarding accident. He fell when wakeboarding and, after a sudden forceful jerk via the tow rope, he was dragged by his left arm. On examination, there was a mass overlying the distal brachialis muscle, which had no contractile function (Fig. 4). Elbow flexion and supination was weakened (4/5); however, the patient had no paraesthesia. Ultrasonography revealed a tear at the musculotendinous junction of the short head of biceps near the junction of upper and middle third of humerus. The long head of biceps muscle and its insertion appeared intact. Nerve conduction studies demonstrated a severe musculocutaneous nerve neuropathy involving the motor branches to biceps, but sparing the cutaneous sensory branch. An MRI was unhelpful.
Because of the delayed presentation and probable muscle atrophy, denervation of the ruptured biceps muscle, and the lengthy recovery period most likely required, it was felt that surgical repair was unlikely to be of great benefit to the patient. The patient agreed not to proceed with any surgery and, 6 months after the initial injury, the minimal loss of power in supination in his nondominant arm was not of great functional significance.
Water-skiing and wakeboarding are physically demanding sporting activities, involving highly co-ordinated movements, extreme upper body torque and sustained isometric contractions of various muscle groups, including the biceps brachii and forearm flexors . They are associated with multiple injury types, of which the most common are strains or sprains, with 13% of injuries involving the upper extremities .
A review of published articles revealed only three previously reported cases of water-skiing related biceps muscle rupture (Table 1). These cases (as well as our own cases) were always associated with a sudden forced extension of the elbow against an eccentrically contracting muscle, especially in a flexed elbow [4,10,11]. The mechanism is similar to avulsion of the flexor digitorum profundus (FDP) tendon in the hand with forced extension of the finger against an actively contracting FDP muscle .
|DiChristina and Lustig ||19-year-old male||Fall during manouevre. Tow rope wrapped around mid forearm||Rupture through muscle belly short head of biceps||Suture repair of ruptured biceps|
|Moorman et al. ||15-year-old male||Jumping over wake when holding onto tow rope with elbow flexed. Rope suddenly went taut||Disruption of long and short head of biceps proximally at the musculotendinous junction with displacement of distal biceps into forearm||Surgical exploration only|
|Carmichael et al. ||17-year-old male||Tow rope held in cubital fossa with elbow flexed. Sudden acceleration of boat, hence arm jerked by boat. No direct strike or hit to upper arm||Medial 40% to 50% biceps muscle torn||Debridement of dusky and noncontractile ruptured biceps|
Patients who rupture their biceps brachii often present with a history of a sudden painful give (or pop) in the upper limb. Diagnosis should include examination for a mass on the anterior arm, which may be tender, pain on elbow extension and decreased strength of elbow flexion and supination [4,11]. Ultrasonography, MRI and X-rays are the most commonly performed investigations.
With numerous advances in fixation methods, early anatomical repair is advocated for biceps tendon ruptures . Military parachutists who suffered sustained biceps muscle disruptions (i.e. a combination of direct blow and forced abduction) reported better outcomes in strength, fatigability, pain and cosmesis with operative intervention [5,6]. However, when biceps muscle rupture was sustained during water-related sporting activities, satisfactory outcomes have been reported with both surgical and nonsurgical measures. DiChristina et al. reported on a patient who had the ruptured biceps muscle re-approximated with interrupted non-absorbable sutures . On evaluation 4 months postoperatively, the patient had regained full strength and returned to all activities, including intercollegiate wrestling. In the case reported by Carmichael et al., the torn portion of biceps muscle appeared nonviable, and hence it was only debrided, leaving 50% to 60% of the muscle . At 8-month follow-up, the patient had a full elbow range of motion, 5/5 strength to manual testing, and had resumed skiing and other sports with no functional limitations. Moorman et al. did not reinsert the biceps muscle because of neurovascular disruption and the necrotic condition of the muscle (at least 3 weeks after the initial injury) . At 1-year follow-up, their patient had less strength on elbow flexion but a normal range of motion of the shoulder, elbow and wrist. He had resumed normal activities and had no limitations related to the injury; hence, he did not undergo further operative intervention. The extent of muscle disruption, the condition of the muscle belly, neurovascular involvement and, in particular, a delay in presentation will influence the decision to operate or not.
We report two further rare cases of biceps brachii muscle rupture sustained during water-skiing and wakeboarding in addition to three cases previously reported in the literature. Sudden forceful extension of the elbow against an isometrically contracting biceps and flexed elbow preceded these injuries. A full history and examination is usually suggestive, with ultrasonography or MRI aiding in the diagnosis. It is important to be vigilant of these injuries, given that early recognition and operative intervention with or without direct muscle repair may optimize outcomes.