Osteochondritis Dissecans in a Young Pitcher: Why Early Recognition Matters
by Jack T. Andrish, MD
Pediatrics Series Editors: Barry Goldberg, MD; Elliott B. Hershman, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 3 - MARCH 97
In Brief: Osteochondritis dissecans of the humeral capitellum is an unusual, but not rare, complication of repetitive stress to the skeletally immature elbow. This case report of a Little League player demonstrates how untreated underlying osteochondrosis resulted in permanent disability. Radiographs are essential. The differential diagnosis includes infection, cysts, and Panner's disease. For nondisplaced fragments, rest is indicated until pain resolves and range of motion returns; surgery or arthroscopy may be needed to remove or repair displaced fragments.
The sports that put the most intense repetitive stress on the elbows of young athletes are the two they often pursue the most zealously—baseball and gymnastics. Overuse injuries such as Little League elbow are the natural consequence. Fortunately, most patients who have Little League elbow will heal when they take a break from the offending activity. However, physicians need to know when the patient's symptoms require radiographic examination for a potentially disabling epiphyseal injury.
History. A 12-year-old boy presented to his regular physician when he began experiencing a sore right elbow. He was active in youth baseball and basketball. At the time of presentation, he was a pitcher and outfielder for his local Little League team. Though he continued to play, his coach noticed a drop in performance. His parents said that his elbow was stiff and that he was frequently unable to fully straighten the elbow, especially after playing ball. His parents reported that their son was very talented and could throw harder than any of his peers. They said he loved baseball so much that he practiced throwing for hours to improve his pitching.
The physical examination at that time revealed a healthy-appearing, average-proportioned prepubescent right-handed 12-year-old boy. No abnormalities were noted other than a 15° flexion contracture of his right elbow; there was no localized tenderness, swelling, or deformity.
The physician diagnosed the condition as probable Little League elbow and advised rest. This diagnosis implied a strain of the musculature about the elbow or a sprain of the capsuloligamentous support. In the absence of direct trauma or significant pain and tenderness, the possibility of a fracture was not considered. In the absence of swelling or other systemic features, arthritis was dismissed.
When the summer came to a close, the patient moved into basketball without difficulty. He no longer complained of elbow pain or soreness, and his performance on the court was outstanding. His parents, however, noted asymmetrical arm swing and stiffness of his right elbow. Baseball came again in the spring, and when the patient resumed pitching, right elbow soreness recurred. His pitching suffered, and he eventually switched to first base.
The patient competed on baseball and basketball teams throughout junior and senior high school. When his performance deteriorated in his senior year because of progressive stiffness of his elbow and repeated locking episodes, he returned to his usual physician who referred him to a sports medicine orthopedist.
Physical examination. Examination of the 17-year-old's right elbow revealed a limited range of motion from 25° of flexion to 125° of flexion (normal is full extension or even 10° of hyperextension to 150° of flexion). Palpable crepitation was noted over the radiohumeral joint with flexion and extension. Mild tenderness to palpation was felt over the lateral aspect of the elbow. The joint was stable. The examination of the wrist and shoulder was unremarkable, as was the examination of the contralateral upper extremity.
Radiographic studies. Symptoms of an intra-articular loose body and crepitation within the joint suggested posttraumatic arthrosis. A plain x-ray revealed a cystic lesion of the humeral capitellum (figures 1a and 1b) and at least one loose body within the elbow joint. An arthrogram (figure 1c), obtained to further define the lesion, revealed two loose bodies and an irregular, eroded humeral capitellum surface.
Diagnosis. The differential diagnosis included infection, a cyst, Panner's disease, osteochondritis dissecans of the elbow, synovial osteochondromatosis, a tumor, and a fracture. It was felt that the patient had osteochondritis dissecans of the elbow.
Treatment. The patient underwent surgical excision of the loose fragments and curettage of the base of the defect. Postoperatively, physical therapy was emphasized for maintenance of range of motion.
Outcome. When last seen, 2 years after surgery, the patient had returned to playing recreational baseball. He denied pain with that activity but did have occasional pain with weight lifting. The physical examination revealed a 22° flexion contracture. He could pronate 30° and supinate 90° (normal is 90° of pronation and 90° of supination). A radiograph demonstrated irregularity of the contour of the humeral capitellum, but the cystic lesion appeared to have healed. Although the joint space was maintained, and no loose bodies were identified, the loss of normal radiocapitellar congruence permanently limited his elbow motion (figure 2).
The differential diagnosis was narrow when the patient's radiographic picture was combined with the clinical history (1). The cystic changes found within bone were benign in appearance. The area was well demarcated without evidence of periosteal reaction. Infection can produce bony erosion like that seen in this patient, but the lack of inflammatory signs or systemic symptoms, combined with the chronicity of the complaints and the patient's good overall health, led away from this consideration.
Simple bone cysts and fibrous lesions are not uncommon in this age-group but most often are found in the metaphysis, not in the epiphysis. Loose bodies in a joint typically suggest synovial osteochondromatosis; however, this disease is a result of cartilaginous or osteocartilaginous metaplasia of the synovium and is frequently associated with very large numbers of intra-articular loose bodies.
The finding of a cystic lesion within the humeral capitellum of a young athlete involved in a throwing sport is characteristic of osteochondritis dissecans. This "quiet necrosis," described by Paget (2) in 1870 and named by König (3) in 1887, is an uncommon, but not rare, finding in patients who have Little League elbow (4). Throwing imposes not only exceedingly large tensile forces on the medial side of the elbow, but also excessive compression forces on the lateral aspect of the joint—the radiocapitellar articulation. The condition is not limited to Little League throwers. The large repetitive loads of gymnastics put similar stress on skeletally immature elbows, sometimes resulting in a similar breakdown (5). Microfracture and eventual avascular necrosis follow this repetitive trauma. Destruction of the overlying articular cartilage with fragmentation and softening of the underlying subchondral bone may be found (6). Loose bodies will frequently be produced, at times leading to more widespread joint degeneration.
Panner's Disease or Osteochondritis?
Clincially and radiographically, osteochondritis dissecans of the elbow is very similar to Panner's disease. Though the exact etiology of these osteochondroses of the humeral capitellum is not known, theories include trauma, ischemia, and genetic causes (7). First described in 1927 (8,9), Panner's disease is characterized by disordered epiphyseal endochondral ossification, which may arise spontaneously.
An identical appearance may arise as a complication of repetitive stress such as that seen with throwing. In fact, there is disagreement about whether osteochondritis dissecans of the humeral capitellum and Panner's disease represent a spectrum of the same pathologic condition or are different processes (1,10-12) though current opinion favors the latter (7).
Panner's disease generally affects children under age 10, whereas osteochondritis dissecans of the elbow affects preadolescents and adolescents. Furthermore, Panner's disease involves the entire epiphysis and is radiographically characterized by radiolucency and fragmentation, similar to Legg-Calvé-Perthes disease of the hip. Osteochondritis dissecans, on the other hand, typically affects the lateral or central portion of the capitellum. The radiographic appearance may include radiolucency of the capitellum, but it may also include loose body formation and secondary changes of hypertrophy of the radial head.
Panner's disease typically resolves with growth and development, whereas osteochondritis dissecans may, and all too often does, lead to degenerative arthritis.
In patients who have osteochondritis dissecans of the capitellum, the status of the dissecans lesion will often direct treatment. Nondisplaced, in situ lesions may heal with rest and protection. Throwing (or whatever the offending activity) should be eliminated until all soreness, tenderness, and stiffness have completely resolved.
Lesions that are loose or partially detached may be salvaged by reattachment and internal fixation. However, loose or displaced dissecans lesions are best managed by surgical excision of the loose fragment and curettage of the base of the defect. The patient in the case study underwent an open procedure to achieve these goals, but arthroscopic removal of loose bodies and debridement of the articular defect is now the procedure of choice (12).
Panner's disease will usually resolve with nonoperative supportive care in skeletally immature patients. They should avoid activities that stress the elbow, such as repetitive throwing in baseball or vaulting and floor exercises in gymnastics, until pain is gone and full motion has returned. However, once the lesion becomes fragmented, healing will not occur (13). Furthermore, skeletal maturity limits the potential for the osteochondroses to heal. Surgery is rarely needed for Panner's disease unless the patient is a young, skeletally mature adult who did not heal and has symptoms, or a child who has a symptomatic loose fragment documented by magnetic resonance imaging or arthrography.
Ominous Warning Sign
We cannot always assume that aches and pains in Little League participants are secondary to minor strains and that most overuse syndromes occurring in this age-group will never lead to permanent structural damage. A flexion contracture in the elbow in a skeletally immature athlete should be taken very seriously, particularly if it involves the dominant elbow in a sport that requires throwing. Limited elbow motion, even when transitory, means trouble.
A plain radiograph should be taken to rule out an underlying osteochondral injury or condition such as osteochondritis dissecans. Magnetic resonance imaging can further aid in the detection of occult osteochondral injury.
Though the young man featured in this report eventually returned to reasonable recreational activities, the sequelae of what was first thought to be Little League elbow will represent some degree of disability for the remainder of his life.
Dr Andrish is an orthopedic surgeon specializing in pediatric and sports medicine orthopedics at the Cleveland Clinic Foundation in Cleveland. Dr Goldberg is director of sports medicine at Yale University Health Services and a clinical professor of pediatrics at Yale University School of Medicine in New Haven, Connecticut. Dr Hershman is assistant director of orthopedic surgery at Lenox Hill Hospital in New York City. Dr Goldberg is an editorial board member of The Physician and Sportsmedicine. Address correspondence to Jack T. Andrish, MD, The Cleveland Clinic Foundation, 9500 Euclid Ave, Desk A51, Cleveland, OH 44195; e-mail to [email protected].
Copyright (C) 1997. The McGraw-Hill Companies. All Rights Reserved