The knee is one of the most frequently injured joints in the human body, with the treatment of knee injuries representing a significant portion of physical therapists’ and orthopaedic physicians’ clinical practice. Consequently, the knee is also one of the most frequently studied and written-about joints in the literature. So why publish a special issue on the knee when it is already so frequently discussed in the literature? The main reason is that things change, and certainly things are changing rapidly in the treatment of specific knee lesions. Also, the sheer volume of literature on surgical techniques and rehabilitation concepts makes it a challenge for any clinician to remain up to date. It is therefore the intent of this special issue to provide clinicians with key updates on the management of selected knee injuries.
SYNOPSIS: Rehabilitation following anterior cruciate ligament surgery continues to change, with the current emphasis being on immediate weight bearing and range of motion, and progressive muscular strengthening, proprioception, dynamic stability, and neuromuscular control drills. The rehabilitation program should be based on scientific and clinical research and focus on specific drills and exercises designed to return the patient to the desired functional goals. The goal is to return the patient’s knee to homeostasis and the patient to his or her sport or activity as safely as possible. Unique rehabilitation techniques and special considerations for the female athlete will also be discussed. The purpose of this article is to provide the reader with a thorough scientific basis for anterior cruciate ligament rehabilitation based on graft selection, patient population, and concomitant injuries.
SYNOPSIS: Anterior cruciate ligament (ACL) injuries in skeletally immature individuals remain a challenge for the child, the parents, orthopaedic surgeons, and physical therapists. The main challenges are the potential risk of recurrent instability, secondary injuries following nonoperative treatment, and the risks involved with surgical treatment due to the vulnerability of the epiphyseal growth plates. We first present the physiological background for considerations that must be made when advising on treatment alternatives for skeletally immature individuals after ACL injury. The implications of continuous musculoskeletal development for treatment decisions are emphasized. No randomized controlled trials have been performed to investigate outcomes of different treatment algorithms. There is no consensus in the literature on clinical treatment decision criteria for whether a skeletally immature child should undergo transphyseal ACL reconstruction, physeal sparing ACL reconstruction, or nonoperative treatment. Additionally, well-described rehabilitation programs designed for either nonoperative treatment or postoperative rehabilitation have not been published. Based on the currently available evidence, we propose a treatment algorithm for the management of ACL injuries in skeletally immature individuals. Finally, we suggest directions for future prospective studies, which should include development of valid and reliable outcome measures and specific rehabilitation programs.
SYNOPSIS: The goal of every orthopaedic surgeon should be to restore anatomy as close as possible to normal. Intense research on reconstruction of the anterior cruciate ligament (ACL) and an advancing knowledge of the anatomy and function of the 2 primary bundles of the ACL have led to techniques of ACL reconstruction that more closely restore normal anatomy. Restoring the ACL footprint is one of the most important goals of the surgery, and the choice between anatomic single-bundle and double-bundle ACL reconstruction is determined by the anatomical features of each patient. After reconstruction, the graft undergoes a complex, lengthy process of remodeling; therefore, inappropriate (early), aggressive rehabilitation can lead to graft failure and compromise the patient’s outcome. The purpose of this article is to provide an overview of the anatomy and function of the ACL, the methods for anatomic single-bundle and double-bundle ACL reconstruction, and our recommendations for postoperative rehabilitation.
SYNOPSIS: The anterior cruciate ligament (ACL) is an important stabilizer of the knee against translational and rotational forces. The goal of anatomic reconstruction of the ACL-deficient knee is to re-create a stable knee that will allow for return to sport and prevent recurrent injury.Multiple graft options exist for ACL reconstruction, and each option has unique advantages and disadvantages. With appropriate patient selection, each graft can be utilized to optimize patient outcomes. Allograft options limit morbidity following ACL reconstruction, but care must be taken with surgical technique and postoperative rehabilitation to allow for graft incorporation. An understanding of the surgical technique and differences between graft options will allow the patient, surgeon, and physical therapist to maximize outcomes following ACL reconstruction. LEVEL OF EVIDENCE: Therapy, level 5.
SYNOPSIS: There is a growing body of evidence documenting loads applied to the anterior cruciate ligament (ACL) for weight-bearing and non–weight-bearing exercises. ACL loading has been quantified by inverse dynamics techniques that measure anterior shear force at the tibiofemoral joint (net force primarily restrained by the ACL), ACL strain (defined as change in ACL length with respect to original length and expressed as a percentage) measured directly in vivo, and ACL tensile force estimated through mathematical modeling and computer optimization techniques. A review of the biomechanical literature indicates the following: ACL loading is generally greater with non–weight-bearing compared to weight-bearing exercises; with both types of exercises, the ACL is loaded to a greater extent between 10° to 50° of knee flexion (generally peaking between 10° and 30°) compared to 50° to 100° of knee flexion; and loads on the ACL change according to exercise technique (such as trunk position). Squatting with excessive forward movement of the knees beyond the toes and with the heels off the ground tends to increase ACL loading. Squatting and lunging with a forward trunk tilt tend to decrease ACL loading, likely due to increased hamstrings activity. During seated knee extension, ACL force decreases when the resistance pad is positioned more proximal on the anterior aspect of the lower leg, away from the ankle. The evidence reviewed as part of this manuscript provides objective data by which to rank exercises based on loading applied to the ACL. The biggest challenge in exercise selection post–ACL reconstruction is the limited knowledge of the optimal amount of stress that should be applied to the ACL graft as it goes through its initial incorporation and eventual maturation process. Clinicians may utilize this review as a guide to exercise selection and rehabilitation progression for patients post–ACL reconstruction.
SYNOPSIS: Injuries to the medial side of the knee are the most common knee ligament injuries. The majority of injuries occur in young athletes during sporting events, with the usual mechanism involving a valgus contact, tibial external rotation, or a combined valgus and external rotation force delivered to the knee. Although most complete grade III medial knee injuries heal, some do not, which can lead to continued instability. For these patients, a thorough understanding of the presenting history and a physical examination are important because these injuries can often be confused with posterolateral corner injuries. The main anatomic structures of the medial side of the knee are the superficial medial collateral ligament, deep medial collateral ligament, and posterior oblique ligament. In addition, accurately locating 3 bony prominences over the medial aspect of the knee—the adductor tubercle, gastrocnemius tubercle, and medial epicondyle—is important to conduct a proper physical examination and for surgical repairs and reconstructions. Clinical diagnosis of medial knee injuries is primarily performed via the application of a valgus stress in full extension and at 30° of knee flexion. In addition, an examination of the amount of anteromedial tibial rotation is performed at 90° of flexion, while the dial test, performed at 30° and 90° of flexion, is important because it evaluates for rotational abnormalities. Valgus stress radiographs are useful to objectively determine the amount of medial compartment gapping and to discern whether there is medial or lateral compartment gapping when a medial or posterolateral corner knee injury cannot be differentiated, especially with a chronic injury. The majority of acute grade III medial knee injuries will heal after a nonoperative rehabilitation program. In most instances when there is a knee dislocation or multiligament injury, a primary repair with sutures may be indicated. In severe midsubstance injuries or chronic medial knee injuries, an anatomic medial knee reconstruction with grafts may be indicated. Rehabilitation principles for acute medial knee injuries involve controlling edema, regaining range of motion, and avoiding any significant stress on the healing ligaments. A well-guided rehabilitation program can result in excellent functional outcomes in the majority of patients.
SYNOPSIS: Knee injuries involving multiple ligaments, which are often associated with tibiofemoral joint dislocations, are complex injuries that are challenging to evaluate and treat. The clinician must have a thorough understanding of knee anatomy and be capable of a detailed physical examination to determine the extent and pattern of injury. Accurate interpretation of imaging studies is crucial but cannot replace the physical examination. The magnitude of deforming forces and amount of translation and rotation of the tibia in relation to the femur determine the risk for neurovascular injury. Most patients with multiligament knee injuries undergo surgical management; however, some patients may be best served by a nonoperative approach. Successful rehabilitation consists of achieving good range of motion and strength, as well as normal gait mechanics, while respecting the stages of healing. LEVEL OF EVIDENCE: Therapy, level 5.
SYNOPSIS: The complex structure of articular cartilage allows for diverse knee function throughout range of motion and weight bearing. However, disruption to the structural integrity of the articular surface can cause significant morbidity. Due to an inherently poor regenerative capacity, articular cartilage defects present a treatment challenge for physicians and therapists. For many patients, a trial of nonsurgical treatment options is paramount prior to surgical intervention. In instances of failed conservative treatment, patients can undergo an array of palliative, restorative, or reparative surgical procedures to treat these lesions. Palliative methods include debridement and lavage, while restorative techniques include marrow stimulation. For larger lesions involving subchondral bone, reparative procedures such as osteochondral grafting or autologous chondrocyte implantation are considered. Clinical success not only depends on the surgical techniques but also requires strict adherence to rehabilitation guidelines. The purpose of this article is to review the basic science of articular cartilage and to provide an overview of the procedures currently performed at our institution for patients presenting with symptomatic cartilage lesions.
SYNOPSIS: Articular cartilage injury is observed with increasing frequency in both elite and amateur athletes and results from the significant acute and chronic joint stress associated with impact sports. Left untreated, articular cartilage defects can lead to chronic joint degeneration and athletic and functional disability. Treatment of articular cartilage defects in the athletic population presents a therapeutic challenge due to the high mechanical demands of athletic activity. Several articular cartilage repair techniques have been shown to successfully restore articular cartilage surfaces and allow athletes to return to high-impact sports. Postoperative rehabilitation is a critical component of the treatment process for athletic articular cartilage injury and should take into consideration the biology of the cartilage repair technique, cartilage defect characteristics, and each athlete’s sport-specific demands to optimize functional outcome. Systematic, stepwise rehabilitation with criteria-based progression is recommended for an individualized rehabilitation of each athlete not only to achieve initial return to sport at the preinjury level but also to continue sports participation and reduce risk for reinjury or joint degeneration under the high mechanical demands of athletic activity.
SYNOPSIS: Preservation of meniscal tissue is paramount for long-term joint function, especially in younger patients who are athletically active. Many studies have reported encouraging results following repair of meniscus tears for both simple longitudinal tears located in the periphery and complex multiplanar tears that extend into the central third avascular region. This operation is usually indicated in active patients who have tibiofemoral joint line pain and are less than 50 years of age. However, not all meniscus tears are repairable, especially if considerable damage has occurred. In select patients, meniscus transplantation may restore partial load-bearing meniscus function, decrease symptoms, and provide chondroprotective effects. The initial postoperative goal after both meniscus repair and transplantation is to prevent excessive weight bearing, as high compressive and shear forces can disrupt healing meniscus repair sites and transplants. Immediate knee motion and muscle strengthening are initiated the day after surgery. Variations are built into the rehabilitation protocol according to the type, location, and size of the meniscus repair, if concomitant procedures are performed, and if articular cartilage damage is present. Meniscus repairs located in the periphery heal rapidly, whereas complex multiplanar repairs tend to heal more slowly and require greater caution. The authors have reported the efficacy of the rehabilitation programs and the results of meniscus repair and transplantation in many studies.
The patient was a 27-year-old man who was a recreational baseball player. He was referred to a physical therapist for a suspected medial meniscus injury following a right-sided lower extremity twisting injury sustained 3 weeks prior. Despite 4 weeks of physical therapist intervention, the patient was unable to successfully return to athletic activities. The patient was then referred to an orthopaedic surgeon, who ordered magnetic resonance imaging of his right knee, which revealed a focal full-thickness chondral lesion at the median patellar ridge.
This case describes the selective use of digital infrared thermal imaging for a 48-year-old woman who was being treated by a physical therapist following left anterior cruciate ligament (ACL) reconstruction with a semitendinosus autograft.