You are in: eMedicine Specialties > Orthopedic Surgery > HAND AND UPPER EXTREMITY Capitellar FractureArticle Last Updated: Aug 30, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Janos P Ertl, MD, Clinical Assistant Professor, Department of Orthopedic Surgery, University of California at Davis; Director of Amputee Clinic, Chief of Orthopedic Trauma, Kaiser Hospital Janos P Ertl is a member of the following medical societies: American Academy of Orthopaedic Surgeons, Hungarian Medical Association of America, Orthopaedic Trauma Association, and Sierra Sacramento Valley Medical Society Editors: Michael S Clarke, MD, Clinical Associate Professor, Department of Orthopedic Surgery, University of Missouri-Columbia School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Dinesh Patel, MD, FACS, Associate Clinical Professor of Orthopedic Surgery, Harvard Medical School; Chief of Arthroscopic Surgery, Department of Orthopedic Surgery, Massachusetts General Hospital; Harris Gellman, MD, Consulting Surgeon, Broward Hand Center, Voluntary Clinical Professor of Orthopedic Surgery and Plastic Surgery, Departments of Orthopedic Surgery and Surgery, University of Miami School of Medicine Author and Editor Disclosure Synonyms and related keywords: capitellum fractures, Hahn-Steinthal fractures, Kocher-Lorenz fractures, elbow fracture, broken arm, arm fracture, distal humerus fractures INTRODUCTIONSection 2 of 11
  Fractures of the capitellum are rare. The complete capitellar fracture pattern was first described in the 19th century (1853) by doctors Hahn and Steinthal; the eponym for this fracture pattern includes their names. Later, doctors Kocher and Lorenz described an additional variation of this fracture pattern; a classification system includes their names. ProblemBecause of the rarity of capitellar fractures, controversies exist regarding the most appropriate treatment. The fracture fragment is intra-articular and requires treatment and reduction to reestablish normal elbow motion. Difficulty arises from the varying sizes of the fracture fragment and from the amount of suitable subchondral bone that is present to achieve stable fixation and to allow early elbow motion. Failure of adequate intervention may result in an incongruous joint, as well as in stiffness, instability, and chronic pain. FrequencyCapitellar fractures account for 0.5-1% of all elbow fractures and 6% of all distal humeral fractures. Capitellar fractures are seen with greater frequency in females than in males; this is thought to be secondary to a greater carrying angle and an increased possibility of osteoporosis in females. In 20% of patients with capitellar fractures, radial head fractures also are found. Capitellar fractures do not occur in children younger than 10 years. Because of the cartilaginous composition of the capitellum in children, a similar injury in a child would be a supracondylar or lateral condylar fracture. EtiologyFractures of the capitellum occur in the coronal plane. Separating the capitellum from the lateral column, capitellar factures are the result of shear forces from a fall onto the outstretched hand or of a fall directly onto the elbow. The capitellum is susceptible to shear forces because its center of rotation is 12-15 mm anterior to the humeral shaft. Capitellar fractures may be associated with radial head fractures and posterior dislocations of the elbow. Other associated injuries include the disruption of the medial (ulnar) collateral ligament, the interosseous membrane, and the distal radioulnar joint. ClinicalThe patient is usually elderly or middle-aged and presents following a fall onto an outstretched extremity or following direct trauma to the elbow. The primary complaints are pain, swelling, and a decreased elbow range of motion (ROM). INDICATIONSSection 3 of 11
The development of smaller screws and absorbable implants has led to more successful results with open reduction and internal fixation. All efforts should be made to reduce a displaced capitellar fragment, either by closed or open techniques. Closed reduction can be attempted for type I fractures (see Staging) under general anesthesia, as described by Ochner and colleagues (see Medical Therapy).1 However, soft-tissue attachments are rare, and stability allowing early motion may not be achieved. The most appropriate treatment of type I capitellar fractures is open reduction and internal fixation. If closed reduction is unsuccessfully attempted, open reduction is indicated. Open reduction is indicated in all displaced fractures of the capitellum and in those for which closed reduction fails. The presence of significant comminution may preclude fixation; surgical excision of the comminuted fragments is then recommended. RELEVANT ANATOMYSection 4 of 11
The capitellum's center of rotation lies 12-15 mm anterior to the axis of the humerus shaft, making the capitellum more susceptible to shear forces. CONTRAINDICATIONSSection 5 of 11
Capitellar fracture treatment is approached similarly to that of any intra-articular fracture. Every effort should be made to repair and stabilize displaced capitellar fractures. However, should a significant amount of comminution be present, fixation may not be possible, with excision of the fragments instead being necessary. No contraindications to surgical treatment exist other than those imposed by the patient's medical status, ability to tolerate anesthesia, and activity level. WORKUPSection 6 of 11
Imaging Studies
StagingCapitellar fractures have been conventionally classified as types I and II, but a more extensive and descriptive classification system, the Bryan and Morrey system, has also been developed.
TREATMENTSection 7 of 11
Medical TherapyClosed reduction can be attempted for type I fractures under general anesthesia, as described by Ochner and colleagues.1 The elbow is extended, distracted, and gently flexed in an attempt to capture the fragment and lock it into place. The elbow is manipulated with fluoroscopic assistance (or permanent radiographs may be obtained to confirm reduction). Closed reduction is best performed under muscle-relaxing anesthesia with fluoroscopic control. Attempts should not be repeated, to avoid additional damage or comminution of the fragment. Should the reduction be unsuccessful or nonanatomic, open reduction is indicated. Surgical TherapySurgical techniques and implants have evolved to the extent that the fixation of small fractures is feasible and reproducible. The literature supports anatomic reduction and the initiation of early motion as the treatment of choice for capitellar fractures. Efforts should be made to reduce and stabilize displaced fractures that block extension. When an attempt at closed reduction is unsuccessful, immediate progress to open reduction is recommended. Preoperative DetailsPreoperative planning involves the following steps:
Intraoperative DetailsThe patient is positioned supine on the operating room table, and the injured extremity is placed on the radiolucent hand table. The following steps are taken:
Postoperative Details
Follow-upDepending on the fixation achieved, the patient should be scheduled for physical therapy for progressive and protected single-plane elbow motion. A plastic, removable splint may be made. The follow-up schedule with the physician, with radiographs at each visit, is as follows:
COMPLICATIONSSection 8 of 11
As with any osteochondral fractures and with intra-articular fractures in general, complications of treatment include loss of ROM, avascular necrosis, malunion, and nonunion. Loss of ROM may arise from closed reduction with immobilization and, often, from surgical excision of the fragment. Because of the rapid revascularization of the fragment, avascular necrosis occurs more often than is recognized. Should the avascular fragment become symptomatic, delayed excision is recommended. Malunion is uncommon and is often caused by delayed identification by the patient and the physician. When malunion occurs, elbow flexion is usually severely restricted. Anterior elbow soft-tissue release and fragment excision are indicated. Nonunion may be isolated or associated with avascular necrosis. If the fragment is large enough and viable, an attempt at refixation may be made. If the fragment is small and symptomatic, excision is indicated. In treating these complications, an anterior capsular release in conjunction with the proposed procedure should be considered. OUTCOME AND PROGNOSISSection 9 of 11
Although some authors have advocated fragment excision, a study by Grantham and colleagues demonstrated unsatisfactory results at 5-year follow-up.4 The greatest complaint was stiffness and instability. In the same study, more favorable results were seen with open reduction and internal fixation. McKee and colleagues also demonstrated improved results with early open reduction and internal fixation, along with early motion.3 A 125º flexion/extension arc was achieved. For excellent patient education resources, visit eMedicine's Breaks, Fractures, and Dislocations Center. Also, see eMedicine's patient education articles Broken Arm and Broken Elbow. FUTURE AND CONTROVERSIESSection 10 of 11
With the evolution of smaller implants, absorbable implants, and biologic surgical techniques, more aggressive attempts at fixation of capitellar fractures will continue to be made. Arthroscopically assisted reduction and percutaneous fixation will also be options. REFERENCESSection 11 of 11
Article Last Updated: Aug 30, 2007 |
