The incidence of hamstring muscle injuries has been estimated to be 3.0–4.1 hamstring strains per 1000 h of match play and 0.4–0.5 per 1000 h of training [2]. The prevalence of complete proximal hamstring ruptures has been estimated to be 9% of all by MRI-evaluated hamstring injuries [3].

Most authors advocate that only in the presence of a complete rupture of the proximal attachment of the musculotendinous complex (Fig. 36.1) should surgical repair be considered [27]. More assertive recommendations have recently been made [8] suggesting that a pure isolated biceps femoris and semitendinosus conjoint tendon avulsion should be repaired in active patients.

Nowadays with elite athletes, according to the common guidelines, acute complete proximal hamstring avulsions/ruptures with loss of function (grade III) should be operated on as soon as posible. In cases where only one of them is torn, the controversy persists. Cohen and Bradley [5] suggested surgical treatment when two out of three hamstring tendons are ruptured at the ischial tuberosity. For athletes, more aggressive recommendations with reattachment of isolated tendon avulsions (BF/ST/SM) can be found [21].

In partial proximal hamstring tears, surgical treatment should be considered since in most of these cases, excellent or good results can be expected after surgical repair [19] (Fig. 36.2).

In adolescents, apophyseal avulsions at sites of proximal hamstring muscle insertions are occasionally seen [30]. Operative treatment has been recommended if the displacement of the avulsed fragment is 2 cm or more [16, 32]. Suggested even more is active operative treatment, and recommended is early surgical fixation if the fracture displacement is more than 1 cm [10]. Dissection was carried down to the gluteal fascia, with care to avoid the posterior femoral cutaneous nerve, which crosses the hamstring from lateral-proximal to medial- distal and can cause hypoesthesia to the posterior thigh when damaged.

Hamstring injuries that disrupt the central tendon enclosed within the muscle belly require a longer recovery time than those injuries involving only muscle, epimysial fascia, or the musculotendinous junction. When injury involves the enclosed central portion of the tendon (Fig. 36.3), the distinction between injury to the hamstring muscle and injury to the hamstring tendon is underappreciated as being a distinct entity. Central tendon disruption was identified in 45% of the biceps femoris injuries and in none of the injuries to the other two muscles [6].

The long time in recovering and a high reinjury rate, the surgical treatment, in our opinion, should be considered, giving tension to the tendon amb reinforcement with anchors in ischial tuberosity. Other authors [33], prior to surgery, use ultrasound transducer placed at the muscle-tendon junction to locate the injury site and metallic anchor loaded with a metallic wire placed in the identified lesion site. Excision of the scar tissue, including the torn portion of the tendon, was then performed and tension-free suturing of the belly remnant of the biceps femoris to the adjacent semitendinosus.

Due to the low incidence of proximal hamstring avulsions, most published reports are retrospective case studies with limited numbers of patients. Technical notes on endoscopical repair have recently been published [7]. These less invasive techniques could have some advantages with minimal disruption of normal anatomy and improved visualization with possible decreased neurovascular complications and decreased bleeding, but it involves some technical challenges of passing and shuttling the suture for repair and increased operative time. This arthroscopic repair would be done to avoid scarring and ischiofemoral impingement on the nerve.

Distal hamstring injuries are rare and usually associated with severe traumas to the knee joint or with other traumatic musculotendinous injuries around the knee [4, 18]. However, isolated distal hamstring tendon avulsions have also been described [24, 31, 35], and operative treatment for these has been recommended (Fig. 36.4).

Muscle strains, including grade III avulsion injuries, are often treated nonoperatively [25]. The surgical treatment of a complete tendon avulsion in professional players allow an anatomic repair and return to full activities following rehabilitation.

Proximal avulsions of the rectus femoris muscle at the anterior inferior iliac spine (AIIS) are uncommon. They have been described in adolescent and young individuals, as well as in sports such as sprinting and kicking the ball.

The footprint may have anatomical variations. More common are the acute total avulsion tears (Fig. 36.5) [11, 12]. The mechanical strength of suture anchors has been found to be equal to fixation through bone tunnels [22]. Ten proximal rectus femoris tears [9] have been reported and treated surgically (Fig. 36.6) in professional football players. The author’s method is reattached to the direct head and secured with bone suture anchors.

Although these proximal ruptures are well described, we have found only one report of a complete rupture of the direct head of the rectus femoris muscle at the musculotendinous junction [34] (Fig. 36.7).

Surgery should be considered if the symptoms (pain, weakness, and loss of function) persist longer than 6 months, which is the time expected for healing.

It has been shown that an athlete is unlikely to return to the previous level of sporting activity after complete proximal hamstring rupture unless treated surgically. On the other hand, no differences between early and late repairs have been identified with regard to functional outcome or return to sport. In elite athletes, early surgical refixation of complete proximal hamstring ruptures is recommended.

The surgical procedure may include excision of adhesions, fasciectomies, and tendon bone reattachments. Occasionally retracted muscles can be reattached to the bone by using a tension-free autograft augmentation reattachment with fascia lata autograft [20] or Achilles allograft [26].