The Rectus Femoris(RF)

Introduction
The Rectus Femoris(RF) is one of the four muscles of the Quadriceps femoris group located in the anterior compartment of the thigh. The Rectus femoris originates at the anterior inferior iliac spine and inserts on the patellar tendon. This muscle is the main flexor of the hip, but also helps with extension of the knee. The rectus femoris is an important muscles in sports that involve kicking and running at high velocities, like soccer and football. The mechanism of injury is usually a forceful contraction of the quadriceps against excessive resistance, such as landing from a jump or forcibly kicking the ball1. The rectus femoris is the only muscle of the thigh that cross the knee and the hip which makes it more susceptible to strains and contusions. Muscle contusion most often are due to a direct blow to the muscle. Strains are a stretching or tearing of muscles or tendons. Grade three strains of the rectus femoris are less likely to occur because the RF is a big muscle and it needs an excessive force to rupture. Although is less likely to happen, when it does happens it requires special attention to help the athlete return to play.
Primary Considerations
Even though most strains are treated with RICES and rehabilitation, grade 3 strains often require surgery. The goal of the surgery is to repair the muscle injured and/or any other structures damaged. When an athlete experiences a grade 3 muscle strain common signs and symptoms are pain, swelling, tenderness and a visible/palpable gap in the muscle. The patient is unable to walk without pain and there is a decrease in range of motion. Patients also complain of discomfort and weakness of the anterior thigh in hip flexion and knee extension. The surgery is done with apposition of the muscle ends using resorbable suture material2. The surgery attempts to restore the rectus femoris muscle function and quicker return to sports/activity.
For patient to have the surgery an MRI had to be taken in addition to other findings described above1. Surgery is only indicated when there is a complete rupture of the muscle and it is usually done in elite athletes. On the other hand, surgery is contraindicated when the patient is not active, patient has problem clotting and anesthesia allergy. With any surgery there comes risk like damage to nerve and blood vessels, risk of infection and delayed healing of the wound.
Special Considerations
Athletic trainers should be on the lookout to prevent muscle strains. Athletes are prone to strain a muscle when they are poorly conditioned, after a workout and their muscles are tired. Research has shown that improper warm-up is one of the multiple causes of muscles strains. Helping the athletes stretch and warm-up correctly before practice would decrease the probability of straining a muscle.
Review of Literature
Surgical Procedure
The anterior approach is the most beneficial for elite athletes and research has shown that has a less probability of re-injury. With this approach the patient is laying supine and under general anesthesia. In the anterior portion of the thigh an incision is made from the anterior inferior iliac spine and extends distally 10cm in line with the outer border of the patella, anterior to the tensor fascia lata muscle belly3,5. With the skin open, the doctor should be able to confirm what the MRI showed, a complete rupture of the rectus femoris. After appropriate tension was established, from proximal to distal side-to-side repair was performed6. The torn ends of the RF were fixed by suturing2. Before closing, some doctors decide to treat patient with plasma rich in growth factor(PRGF) using the Anitua technique1. This technique is used to improve recovery time.
Comparison
There are two routes a physician/athletic trainer and athlete can choose to rehabilitate the quadriceps muscle. There is a conservative approach and the surgical approach. The conservative treatment involves immediate RICES and rehabilitation exercises when tolerated. Using nonoperative or conservative treatment can help the athlete return to play faster, but often leads to re-injury. Nonoperative measures help preserve the function of the muscle in elite-level athletes7. The rehabilitation time for conservative treatment 5-6 months. The surgical approach is more beneficial for a grade 3 rectus femoris strain. Even though the recovery time is longer, the re-injury probability is less. The recovery time for the surgical treatment is 7-8 months. Both treatments are presented to the patient and they chose which route the want to go with.

Outcomes and Evidence
Clinician always has to keep in mind that the athlete will pick whichever treatment he/she thinks is best for him/her. Research showed that 74% of the patients had excellent or good results and they returned to competition after an average of 5 months2. Only on patient underwent a re-operation due to re-injury after rehabilitation was classified as poor2. There is lack of research on the rate of recurrence after surgery. Most studies report no recurrence in the patients treated surgically. After surgery, the patients used crutches for 1-2 weeks and full weightbearing was limited until pain was present. Patients were suggested to keep operated leg on a pillow and slowing starting to stretch the hip. Pool training and walking was started between 3-4 weeks. Eccentric exercises were allowed at 6 weeks and at 8 weeks jogging and running were permitted after surgery4. Weight training started between 8-12 weeks. Working on balance, coordination and strength was achieved with physical therapy. At 12-24 weeks ball exercises were introduced, for example kicking, sprinting and jumping. At 3 and 6 months physicians performed strength testing, if hip flexion was equal to uninjured side, return to play was allowed4.
Other Information
Injuries to the quadriceps and the hamstrings muscles are very common. In soccer, specifically the incidence in hamstrings injuries are 37% and quadriceps 19% according to research1. Injuries to the rectus femoris in soccer players occurs in less than 1%, but it is the most strained muscle in the quadriceps muscles. There is no “golden rule” regarding the best treatment for rectus femoris rupture. There has not been sufficient research to the determine which course of action is better. It all comes downto the experience of the clinician and patient preference.