CHAPTER 6
Knee
Case Study 6.1: Acute Anterior Cruciate Ligament Tear
Karen M. Myrick
SETTING: ORTHOPEDIC URGENT CARE
Definition and Incidence
The anterior cruciate ligament (ACL) is one of the most common traumatic knee injuries. The ACL is one of the primary stabilizers in the knee, and prevents anterior displacement of the tibia on the femur. An estimated 120,000 ACL injuries affect athletes in the United States alone annually (Beynnon et al., 2014).
Patient
Patient presents with the chief complaint of left “knee pain.” He describes a history of playing football at his high school 2 days ago. He states, “I was running down field when the whistle blew; I stopped as the play ended, and was going to go back to the huddle. No one was right near me; suddenly, I felt a pop, and it felt as if my knee went around in a circle. I fell to the ground.” He was helped off the field by the athletic trainer, coach, and team doctor, but walked under his own power. He describes the swelling as immediate, and this has slightly receded over the past 2 days. Discomfort is well located in the left knee and mild, rated as a 2 out of 10. Pain is associated with a limp, favoring the left leg. He has been using a short, hinged brace that was placed by the athletic trainer, and this helps him to feel a little more stable. He tried ibuprofen, 800 mg once or twice, but really did not find this to make a difference in the swelling or discomfort. Applying ice 20 minutes four to five times a day has been beneficial in reducing both swelling and discomfort.
Social History
This 17-year-old male is in his senior year of high school, and this was his first game of the season. He has been recruited to play at the collegiate level. His anger, frustration, and situational depression are evident throughout the visit. It is likely that given the injury, he, along with his parents, will need to determine the course of treatment, which can be nonoperative or operative. If he chooses operative treatment, the rehabilitation will include approximately 6 months of physical therapy prior to allowing him a return to play status.
CLINICAL PEARL
The majority of ACL tears occur from a noncontact mechanism of injury (Waldén et al., 2015).
Physical Assessment
The patient is a 17-year-old male who is in no acute distress, but demonstrates hesitancy and some discomfort throughout the physical examination. He is 6′0″ and weighs 213 lb. His gait is antalgic, demonstrating a shortened stance phase on the left knee, and weight bearing with approximately 15 degrees of flexion. On inspection, there is a moderate joint effusion, and no open cuts or abrasions. With palpation, the moderate joint effusion is confirmed with a positive buldge sign and fullness noted in the suprapatellar pouch. Range of motion in the knee is from 5 to 130, and he prefers to hold his knee at a slightly flexed position of approximately 10 degrees. There is no solid block with motion, but a description of “tightness” and “stiffness” from the patient with extremes of motion. A positive Lachman’s test is elicited, with increased translation and a soft end point on this left knee. There is also a positive flexion pinch test, which correlates with tenderness to palpation of the medial posterior joint line. With valgus stressing, there is increased anterior translation of the tibia at 30 degrees, but not at 0 degrees; varus stressing is solid, without increased motion. Anterior drawer is positive, and a Pivot shift test is equivocal; no clunk is elicited at 20 to 30 degrees of flexion with a valgus force and the foot in internal rotation. Quadriceps and hamstring strength are 4 out of 5 and seemingly inhibited by discomfort. There are no focal neurological deficits in the left lower extremity.
Diagnostic Evaluations
A radiograph was not obtained, due to the lack of yield on information that would be likely in this patient. An MRI was obtained. The MRI demonstrated a completely torn ACL, and a medial meniscus tear (see Figure 6.1).
Diagnosis
ACL tear and medial meniscus tear.
Interventions
The patient was placed into a long leg, hinged knee brace, locked at 20 degrees of flexion, and he was given crutches to use until his follow-up with the orthopedic surgeon. Follow-up within 3 to 5 days was arranged with the surgeon for discussion of all options, including surgical intervention. A copy of the patient’s MRI was given to him to bring to the consultation.
FIGURE 6.1 An MRI demonstrating an anterior cruciate ligament tear and medial meniscus tear.
Patient Education
It is very important to educate both the patient and his parents about the possible treatment options for treatment of ACL tears, which include operative and nonoperative management. Equally important is educating the patient and his family to avoid activity, especially cutting and pivoting maneuvers, until they follow up with the orthopedic surgeon. The potential for further damage to the knee joint is high, including damage to the articular cartilage with the shearing forces that will be present without an intact ACL.
Follow-Up Evaluation
As this injury requires surgical consultation, it is possible that the nurse practitioner may not follow up directly with the patient. If the nurse practitioner is in a setting working collaboratively with an orthopedic surgeon, the nurse may perform the preoperative and postoperative care of the patient, and may be in a position to assist in the operating room. For the primary care nurse practitioner, it is likely the patient will return after surgical intervention and rehabilitation has been completed, and the patient is discharged from the specialist. Also highly likely is that the nurse practitioner will care for patients in a variety of stages of ACL injury and rehabilitation.
REFERENCES
Beynnon, B. D., Vacek, P. M., Newell, M. K., Tourville, T. W., Smith, H. C., Shultz, S. J., & Johnson, R. J. (2014). The effects of level of competition, sport, and sex on the incidence of first-time noncontact anterior cruciate ligament injury. American Journal of Sports Medicine, 42(8), 1806–1812.
Waldén, M., Krosshaug, T., Bjørneboe, J., Einar Andersen, T., Faul, O., Hägglund, M., & Andersen, T. E. (2015). Three distinct mechanisms predominate in non-contact anterior cruciate ligament injuries in male professional football players: A systematic video analysis of 39 cases. British Journal of Sports Medicine, 49(22), 1–10.
Case Study 6.2: Acute Meniscus Tear
Karen M. Myrick
SETTING: ORTHOPEDIC URGENT CARE
Definition and Incidence
The meniscus is the C-shaped shock-absorbing cartilage in the tibiofemoral joint of the knee. Meniscal tears are the most common knee injury, and seen across the life span (Xu & Zhao, 2015).
Patient
Patient presents with the chief complaint of right “knee pain.” She describes a history of playing with her 6-year-old daughter 5 days ago, kicking a soccer ball around in the backyard. When she attempted to kick the ball with her left foot toward the goal, her planted and slightly bent right leg twisted and she felt discomfort. She thinks that she may have heard or felt a “pop.” She did not fall, but was unable to continue playing. She walked home with her daughter, and iced her knee. The ice helped the discomfort that was 5 out of 10, 10 being the worst. There was no swelling that night, any bruising, or ecchymosis. When she woke up the following day, she noticed that there was a moderate amount of swelling in the knee, which has decreased slightly, but is still present. Discomfort is located in the right knee, medial side, and mild, rated as 2 out of 10. She has been taking Naprosyn 500 mg twice a day since, which helps the aching discomfort, but has not resolved the swelling.
CLINICAL PEARL
The patient with a meniscus tear usually will not have swelling immediately following the injury. It is most common for any swelling related to a meniscus tear to develop within 48 hours. This is in contrast to the ACL tear, where an immediate joint effusion (hemarthrosis) is commonplace. Note that both problems may present with the patient feeling a “pop” during the time of injury.
Social History
This 39-year-old female is a first-grade teacher and mother of two. She is married and has a supportive husband who works as an accountant. She is active and was training for a marathon in 4 months.
CLINICAL PEARL
Meniscus tears can occur in a vascular or an avascular portion of the meniscus. When the tear is in the area of the meniscus that is avascular, it is likely part of the constellation of symptoms that are associated with degenerative joint disease. When the tear is in the vascular (red) zone, the tear should be repaired as soon as possible, due to the likelihood for healing if treated urgently (Sancheti, Razi, Ramanathan, & Yung, 2010). An MRI can assist in determining the area of the meniscus tear.
Physical Assessment
The patient is a 39-year-old female who is not in any acute distress, but has some tenderness with examination. She is 5′5″ and weighs 131 lb. Her gait demonstrates a normal swing and stance phase, and is not antalgic. On inspection, there is a mild joint effusion, and no open cuts or abrasions. Palpation reveals a mild joint effusion with a positive bulge sign and slight fullness noted in the suprapatellar pouch, and point tenderness to palpation of the medial posterior joint line. Range of motion in the knee is full from 0 to 135 degrees. A positive flexion pinch test is identified, with the patient feeling pain over the medial aspect of the knee with full flexion. There is no ligamentous laxity with varus or valgus stressing, and a negative Lachman’s test and negative Anterior drawer test. Quadriceps and hamstring strengths are 5 out of 5 and equal to the noninjured leg. There are no focal neurological deficits in the left lower extremity.
Diagnostic Evaluations
A radiograph of the right knee was obtained, evaluating the anteroposterior (AP) view, the lateral view, and a sunrise view. Radiographs demonstrate mild degenerative joint disease with medial joint space narrowing, a small osteophyte on the medial femoral condyle, and no fracture or dislocation, as shown in Figure 6.2.
Diagnosis
Medial meniscus tear.
Interventions
The patient was discharged with a hinged knee brace for support and comfort.
Patient Education
Education for patients with a meniscus tear will assist them in having a better understanding of their injury and their treatment options. The potential for further damage to the knee joint is present, and limiting high impact or cutting and pivoting activities in the acute phase is recommended until follow-up.
FIGURE 6.2 Radiograph of the knee demonstrating mild degenerative changes.
Follow-Up Evaluation
Follow-up is recommended at 2 weeks, to assess the patient’s symptoms and level of impact these symptoms are having on activities of daily living. At the 2-week mark, this patient continued to have mechanical symptoms, those of locking, catching, and giving way. Her effusion had subsided. Because of her symptomatology, an MRI was obtained. The MRI demonstrated a small tear of the medial meniscus. Treatment options at this time were presented to the patient. She could undergo a trial of formalized physical therapy to strengthen the muscles surrounding the knee and the hip and core; she could try an injection with hyaluronic acid (Synvisc, Hyalgan, Gel-One); or she could opt for a consultation with an orthopedic surgeon for possible arthroscopic debridement. She opted for a 6-week course of physical therapy, and a return visit for follow-up.
For the primary care nurse practitioner, he or she will order and assess the effectiveness of physical therapy, having the patient return at the end of a 6-week course. It is also likely that the primary care nurse practitioner will learn the techniques of intra-articular injection, and perform this in his or her office. The treatment is guided by the patient’s symptoms and tolerance of those symptoms. The nurse practitioner will care for patients who have had meniscus injuries, and a keen knowledge of the options and treatment plans is important. This patient returned at the 6-week postphysical therapy mark and had no further discomfort.
