Acute Injuries

Sprains, strains, and contusions account for the majority of musculoskeletal injuries. A sprain is an injury to a ligament or joint capsule. A strain is an injury to a muscle or tendon. A contusion is a crush injury to any soft tissue. The history of the injury can be unclear, but it is especially helpful in assessing knee and shoulder injuries. More severe injuries, indicating structural derangement, can have acute signs and symptoms such as immediate swelling, deformity, numbness or weakness, inability to continue playing, inability to walk without a limp, a loud painful pop, mechanical locking of the joint, or the sensation of instability. Most sprains are graded 1-3, with grade 1 meaning that some fibers have been torn with no evidence of laxity of the ligament when tested on physical examination. A grade 2 means more fibers are torn resulting in some laxity of the ligament but a good end point, meaning not all fibers are torn. A grade 3 sprain means all the fibers are torn, and testing of the ligaments results in a “mushy” endpoint on physical examination. Strains are also graded 1-3, with a grade 1 causing mild pain with testing the muscle and very little weakness. Grade 2 injuries cause more pain and moderate weakness with testing the muscle. Grade 3 muscle strains are complete rupture of the muscle or tendon and result in marked weakness and sometimes a palpable defect in the muscle or tendon.

Overuse Injuries

Overuse injuries are caused by repetitive microtrauma that exceeds the body’s rate of repair. This occurs in muscles, tendons, bone, bursae, cartilage, and nerves. Overuse injuries occur in all sports but more commonly in sports emphasizing repetitive motion (swimming, running, tennis, gymnastics). Factors can be categorized into extrinsic (training errors, poor equipment or workout surface) and intrinsic (athlete’s anatomy or medical conditions). Training error is the most commonly identified factor. At the beginning of the workout program, athletes might violate the 10% rule: Do not increase the duration or intensity of workouts more than 10% per week. Intrinsic factors include abnormal biomechanics (leg-length discrepancy, pes planus, pes cavus, tarsal coalition, valgus heel, external tibial torsion, femoral anteversion), muscle imbalance, inflexibility, and medical conditions (deconditioning, nutritional deficits, amenorrhea, obesity). The athlete should be asked about the specifics of training. Runners should be asked about their shoes, orthotics, running surface, weekly mileage or time spent running per week, speed or hill workouts, and previous injuries and rehabilitation. When causative factors are identified, they can be eliminated or modified so that after rehabilitation the athlete does not return to the same regimen and suffer reinjury.

For athletes engaged in excessive training that causes an overuse injury, curtailing all exercise is not usually necessary. Treatment is a reduction of training load (relative rest) combined with a rehabilitation program designed to return athletes to their sport as soon as possible while minimizing exposure to reinjury. Early identification of an overuse injury requires less alteration of the workout regimen.

The goals of treatment are to control pain and spasm to rehabilitate flexibility, strength, endurance, and proprioceptive deficits (Table 679-1). In many overuse injuries, the role of inflammation in the process is minimal. For most injuries to tendons, the term tendinitis is obsolete because there is little or no inflammation on histopathology of tendons. Instead, there is evidence of microscopic trauma to the tissue. Most of these entities are now more appropriately called tendinosis and, when the tendon tissue is scarred and very abnormal, tendinopathy. There is little role for anti-inflammatory medication in the treatment except as an analgesic.

Table 679-1 STAGING OF OVERUSE INJURIES

GRADE	GRADING SYMPTOMS	TREATMENT
I	Pain only after activity Does not interfere with performance or intensity Generalized tenderness Disappears before next session	Modification of activity, consider cross-training, home rehabilitation program
II	Minimal pain with activity Does not interfere with performance More localized tenderness	Modification of activity, cross-training, home rehabilitation program
III	Pain interferes with activity and performance Definite area of tenderness Usually disappears between sessions	Significant modification of activity, strongly encourage cross-training, home rehabilitation program, and outpatient physical therapy
IV	Pain with activities of daily living Pain does not disappear between sessions Marked interference with performance and training intensity	Discontinue activity temporarily, cross-training only, oral analgesic, home rehabilitation program, and intensive outpatient physical therapy
V	Pain interferes with activities of daily living Signs of tissue injury (e.g., edema) Chronic or recurrent symptoms	Prolonged discontinuation of activity, cross-training only, oral analgesic, home rehabilitation program, and intensive outpatient physical therapy

Initial Evaluation of the Injured Extremity

Initially, the examiner should determine the quality of the peripheral pulses and capillary refill rate as well as the gross motor and sensory function to assess for neurovascular injury. The first priorities are to maintain vascular and skeletal stability.

Criteria for immediate attention and rapid orthopedic consultation include vascular compromise, nerve compromise, and open fracture. The exposed wound should be covered with sterile saline-soaked gauze, and the injured limb should be padded and splinted. Pressure should be applied to any site of bleeding. Additional criteria include deep laceration over a joint, unreducible dislocation, grade III (complete) tear of a muscle-tendon unit, and displaced, significantly angulated fractures (depends on the bone involved, the degree of displacement and angulation, and neurovascular status of the extremity).

Transition From Immediate Management to Return to Play

Rehabilitation of a musculoskeletal injury should begin on the day of the injury.

Phase 1

Limit further injury, control swelling and pain, and minimize strength and flexibility losses. This requires the use of an appropriate device such as crutches or a sling, ice, compression, elevation, and analgesia. Crutches, air stirrups for ankle sprains, slings for arm injuries, and elastic wraps (4-8 in) for compression are a reasonable inventory of office supplies. Ice in a plastic bag is placed directly on the skin for 20 min continuously, 3 to 4 times per day until the swelling resolves. Compression limits further bleeding and swelling but should not be so tight that it limits perfusion. Elevation of the extremity promotes venous return and limits swelling. A nonsteroidal anti-inflammatory drug (NSAID) or acetaminophen is indicated for analgesia.

Pain-free isometric strengthening and range of motion should be initiated as soon as possible. Pain inhibits full muscle contraction; deconditioning results if the pain and resultant nonuse persist for days to weeks, thus delaying recovery. Education about the nature of the injury and the specifics of rehabilitation exercises, including handouts with written instructions and drawings demonstrating the exercises, are helpful.

Phase 2

Improve strength and range of motion (i.e., flexibility) while allowing the injured structures to heal. Protective devices are removed when the patient’s strength and flexibility improve and activities of daily living are pain free. Flexibility can then be improved by a program of specific stretches, held for 15-30 sec for 3 to 5 repetitions, once or twice daily. A physical therapist or athletic trainer is invaluable in guiding the athlete through this process. Protective devices might need to be used for months during sports participation. Swimming, water jogging, and stationary cycling are good aerobic exercises that can allow the injured extremity to get relative rest or be used pain free while maintaining cardiovascular fitness.

Phase 3

Achieve near normal strength and flexibility of the injured structures and further improve or maintain cardiovascular fitness. Strength and endurance are improved under controlled conditions using elastic bands and eventually free weights or exercise equipment. Proprioceptive training allows the athlete to redevelop a kinesthetic sense, which is critical to joint function and stability.

Phase 4

Return to exercise or competition without restriction. When the athlete has reached nearly normal flexibility, strength, proprioception, and endurance, he or she can start sports-specific exercises. The athlete will make the transition from the rehabilitation program to functional rehabilitation appropriate for the sport. Substituting sports participation for rehabilitation is inappropriate; rather, there should be progressive stepwise functional return to a full activity or play program. For instance, a basketball player recovering from an ankle injury might begin a walk-run-sprint-cut program before returning to competition. At any point in this progression, if pain is experienced, the athlete needs to stop, apply ice, avoid running for 1-2 days, continue to do ankle exercises, and then resume running at a lower intensity and progress accordingly.

Relative Rest and Return-to-Play Guidelines

Relative rest means that the athlete can do whatever he or she wants as long as the injured structures do not hurt during or within 24 hr of the activity. Exercising beyond the pain threshold delays recovery.

Differential Diagnoses of Musculoskeletal Pain

Traumatic, rheumatologic, infectious, hematologic, psychologic, and oncologic processes can cause the presenting complaint of musculoskeletal pain. Symptoms such as fatigue, weight loss, rash, multiple joint complaints, fever, chronic or recent illness, and persistence of pain suggest diagnoses other than sports-related trauma. Incongruity between the patient’s history and physical examination findings should lead to further evaluation. A negative review of systems with an injury history consistent with the physical findings suggests a sports-related etiology.

Bibliography

Khan KM, Cook JL, Kannua P, et al. Time to abandon the “tendonitis” myth. Br Med J. 2002;324:626-627.

Sharma P, Maffulli N. Tendon injury and tendinopathy: healing and repair. J Bone Joint Surg Am. 2005;87:187-202.

Van Tulder M, Malmivaara A, Koes B. Repetitive strain injury. Lancet. 2007;369:1815-1822.

679.1 Growth Plate Injuries

Gregory L. Landry

About 20% of pediatric sports injuries seen in the emergency department are fractures, and 25% of those fractures involve an epiphyseal growth plate or physis (Chapter 675). Growth in long bones occurs in 3 areas and is susceptible to injury. Immature bone can be acutely injured at the physis (Salter-Harris fractures), the articular surface (osteochondritis dissecans), or the apophysis (avulsion fractures). Boys suffer about twice as many physeal fractures as girls; the peak incidence of fracture is during peak height velocity (girls, 12 ± 2.5 yr; boys, 14 ± 2 yr). The physis is a pressure growth plate and is responsible for longitudinal growth in bone. The apophysis is a bony outgrowth at the attachment of a tendon and is a traction physis. The epiphysis is the end of a long bone, distal or proximal to the long bone, and contains articular cartilage at the joint.

The most common physeal injuries are to the distal radius, followed by phalangeal and distal tibial fractures. About 94% of forearm fractures in skateboarding, roller skating, and scooter riding involve the distal radius. Physeal injuries at the knee (distal femur, proximal tibia) are rare. Growth disturbance following a growth plate injury is a function of location and the part of the physis fractured. These factors influence the probability a physeal bar will form, resulting in growth arrest. The areas making the largest contribution to longitudinal growth in the upper extremities are the proximal humerus and distal radius and ulna; in the lower extremities, they are the distal femur and the proximal tibia and fibula. Injuries to these areas are more likely to cause growth disturbance compared with physeal injuries at the other end of these long bones. The type of the physis fracture relative to risk of growth disturbance is described by the Salter-Harris classification system (see Table 675-1). A grade I injury is least likely to result in growth disturbance, and grade V is the most likely fracture to result in growth disturbance.

Osteochondritis dissecans (OCD) affects the subchondral bone and overlying articular surface (Chapter 669.3). With avascular necrosis of subchondral bone, the articular surface can flatten, soften, or break off in fragments. The etiology is unknown but may be related to repetitive stress injury in some patients. In children and adolescents, 51% of lesions occur on the lateral aspect of the medial femoral condyle, 17% occur on the lateral condyle, and 7% occur on the patella. Bilateral involvement is reported in 13-30% of cases. Other joints where OCD lesions are also seen are the ankle (talus), elbow (usually involving the capitellum), and radial head. OCD classically affects athletes in their 2nd decade. The most common presentation is poorly localized vague knee pain. There is rarely a history of recent acute trauma. Some OCD lesions are asymptomatic (diagnosed on “routine” radiographs), whereas others are manifested as joint effusion, pain, decreased range of motion, and mechanical symptoms (locking, popping, catching). Activity usually worsens the pain.

Physical examination might show no specific findings. Sometimes tenderness over the involved condyle can be elicited by deep palpation with the knee flexed. Diagnosis is usually made with plain radiographs (Fig. 679-1). A tunnel view radiograph should be obtained to better view the posterior two thirds of the femoral condyle. Patients with OCD should be referred to an orthopedic surgeon for further evaluation.

Figure 679-1 Osteochondritis dissecans in the elbow.

(From Anderson SJ: Sports injuries, Curr Prob Pediatr Adolesc Health 35:105–176, 2005.)

Avulsion fractures occur when a forceful muscle contraction dislodges the apophysis from the bone. They occur most commonly around the hip (Fig. 679-2) and are treated nonsurgically. Acute fractures to other apophyses (knee and elbow) require urgent orthopedic consultation. Chronically increased traction at the muscle-apophysis attachment can lead to repetitive microtrauma and pain at the apophysis. The most common areas affected are the knee (Osgood-Schlatter and Sindig-Larsen-Johannson disease), the ankle (Sever disease) (Fig. 679-3), and the medial epicondyle (Little League elbow). Traction apophysitis of the knee and ankle can potentially be treated in a primary care setting. The main goal of treatment is to minimize the intensity and incidence of pain and disability. Exercises that increase the strength, flexibility, and endurance of the muscles attached at the apophysis, using the relative rest principle, are appropriate. Symptoms can last for 12-24 mo if untreated. As growth slows, symptoms abate.