J Oral Maxillofac Surg 49:698-702,1991

Early Immobilization of Mandibular Fractures: A Retrospective Study PHILIP L. MALONEY, DMD,* TIMOTHY B. WELCH, DDS,t AND H. CHRIS DOKU, DMD, MSD:f: This study reviews the treatment outcome of 204 fractures in 131 patients over a 33-month period. In the total group, an infection rate of 4.4% was experienced, which is comparable with other reports. However, in complaint patients immobilized within 72 hours of injury, there was a 0% incidence of bone infection in 111 fractures treated by closed reduction and a 2% (one case) incidence of bone infection in 50 fractures treated by open reduction. Thus, of the of 161 fractures treated by closed and/or open reduction with early immobilization in complaint patients, the incidence of posttreatment bone infection was 0.6%. It was not significant whether teeth in the line of fracture were retained or removed. This study supports the principle that compound fractures of the mandible should to be immobilized within 72 hours of the initial trauma.

ciated with an infected fracture markedly prolongs treatment and often adds significant cosmetic, functional, and economic disability for the patient. Twenty years ago in the oral surgery department at Boston City Hospital, a file was established that contained basic information on all fracture patients. This folder included the patient's age, sex, date and hour of trauma, date and hour first seen, cause of fracture, time interval between trauma and closed reduction with maxillomandibular fixation, time interval from trauma to open reduction or other procedures such as placement of splints or pins, location of fracture, whether it was simple or compound, teeth in the line of fracture and their disposition, and time of any tooth extraction and antibiotics administered. On review and interpretation of these data, principles were established for the managemeht of patients with mandibular fractures in our institution. Our cases primarily involved indigent persons whose diet and compliance with the use of prescribed antibiotics and postoperative appointments were frequently inconsistent. We are aware that there are many other variables, not the least of which is the diversity of staff and residents treating these cases. However, it is still possible to establish principles in the management of mandibular fractures based on the retrospective study and interpretation of these data coupled with

The treatment of patients with mandibular fractures is a common occurrence.in the practice of oral and maxillofacial surgery. Despite a wealth of experience in this area, the treatment outcome in a consistent percentage of patients is complicated by infection of bone at the fracture site. The reports of various authors cite a posttreatment bone infection rate between 0.4% and 8%.1-8 The incidence of postoperative infections at fracture sites was noted to increase when open reduction was performed. Although the numbers are small, the morbidity assoReceived from the Department of Oral and Maxillofacial Surgery, Tufts University School of Dental Medicine, Boston. * Professor; Director, Department of Dentistry and Oral and Maxillofacial Surgery, and Director, Maxillofacial Trauma Service, Boston City Hospital; Clinical Professor of Oral and Maxillofacial Surgery, Boston University Goldman School of Graduate Dentistry. t Former Chief Resident, Advanced Education Program; currently, Coordinator of Residency Education, Department of Oral and Maxillofacial Surgery, Loma Linda University, Loma Linda, CA. t Professor and Chairman; Associate Dean for Hospital Affairs. Address correspondence and reprint requests to Dr Maloney: Department of Dentistry and Oral and Maxillofacial Surgery, Boston City Hospital, 818 Harrison Ave, Boston, MA 02118. © 1991 American Association of Oral and Maxillofacial surgeons 0278-2391/91/4907-0007$3.00/0

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an understanding of the clinical findings and the pathology involved. These principles are based on the hypothesis that if a compound fracture is not immobilized within 72 hours of the injury, an acute intramedullary infection occurs at the fracture site which is de facto an acute osteomyelitis. Furthermore, if immobilization and antibiotic therapy are not achieved within 7 days of injury, there is a strong possibility that the vascularity of the bone will be compromised, which translates into an increased risk of progression to a chronic suppurative osteomyelitis at the fracture site. The following is a list of our principles in the management of mandibular fractures. 1. If a compound fracture of the mandible is properly immobilized and appropriate antibiotics are administered within 48 hours, or a maximum of 72 hours from the time of injury, the patient will proceed to timely healing, whether treated by closed or open methods. Even temporary immobilization with Ivy loops or individual wires (rosettes) is usually adequate if arch bars can not be placed immediately. 2. If a fracture is simple, delay in treatment will not result in a bone infection whether treated by open or closed methods. 3. When the interval between trauma and initial immobilization of a compound fracture exceeds 48 to 72 hours, the patient should be presumed to have an acute infection of bone at the fracture site. This acute infection of the medullary portion of bone is de facto an acute osteomyelitis. Thrombophlebitis and obliteration of the vessels usually has not yet occurred so that the infection will respond and the fracture will usually heal if treated by a closed reduction and/or external pin fixation combined with antibiotic therapy; usually intravenous (IV) penicillin for 7 to 21 days followed by oral penicillin for 4 to 6 weeks. The exact duration of IV or oral antibiotic therapy is determined by the length of delay in initial immobilization of the compound fracture. If the patient is allergic to penicillin, erythromycin or c1indamycin is substituted. 4. When there has been a delay in initial immobilization of more than 72 hours, but less than 10 days, and adequate reduction cannot be achieved by closed reduction and/or pins, one may proceed by initially stabilizing the fracture by closed reduction, administer IV antibiotics for 10 to 21 days, and then perform an open reduction with intraosseous fixation. The

small vessels are not obliterated in the early acute phase and the infection will usually resolve in 10 to 21 days with a combination ofIV antibiotics and the maxillomandibular or external pin fixation. 5. If a compound fracture is older than 7 to 10 days when first immobilized, and an open reduction is performed even after a lO-day period of maxillomandibular fixation and antibiotic therapy, the patient is at significant risk of developing a postoperative chronic suppurative osteomyelitis. 6. All patients with compound mandibular fractures should be given antibiotics. Penicillin is the antibiotic of choice; however, if the patient is allergic to penicillin, erythromyin or c1indamycin is substituted. It has been our observation that adherence to the aforementioned principles has minimized the incidence of posttreatment bone infection in the management of mandibular fractures. To test the validity of these principles, a retrospective study was conducted of mandibular fractures treated over a 33-month period.

MaterialS and Methods Mandibular fractures treated at our institution between March 1, 1984 and December 31, 1986 were retrospectively studied. Only those cases where detailed records were retrievable and the patients were followed to completion were included in this study. Within these parameters, 204 fractures in 131 patients were reviewed. The data analyzed were obtained from departmental files supplemented with information from the inpatient and outpatient hospital records, where applicable. The 204 fractures in 131 patients consisted of 72 simple and 132 compound fractures; there were no comminuted fractures. The 131 patients included 104 males and 27 females. The age distribution of the patients was 0 to 9 years (2); 10 to 19 years (13); 20 to 29 years (77); 30 to 39 years (27); 40 to 49 years (7); 50 to 59 years (3); and over 60 years (2). The patients were divided into five specific groups to best evaluate the effectiveness of early immobilization in the prevention of posttreatment infection at the fracture site. GROUP

1:

CLOSED REDUCTION OR EXTERNAL

PINS-EARLY IMMOBILIZATION

There were 57 patients with 86 fractures ..Thirtyfive were simple and 51 were compound fractures.

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EARLY IMMOBILIZATION OF MANDIBULAR FRACTURES

The time from injury to immobilization was less than 72 hours. Definitive treatment consisted of closed reduction or external pin fixation, and antibiotics if the fracture was compounded. There were teeth in the line offracture in 51 fractures. The teeth were retained in the line of fracture in 45 instances and removed in six instances. All patients were judged to be compliant with fixation and/or diet and prescribed antibiotics. No bone infections occurred at the fracture sites. GROUP 2: CLOSED REDUCTION OR EXTERNAL PINS-DELA YEO IMMOBILIZATION

There were 24 patients with 30 fractures. Twelve were simple and 18 were compound fractures. The time from injury to immobilization was greater than 72 hours, ranging from 4 to 40 days, the average being 8 days. There were 7 patients with 4 days delay in immobilization; 5 with a 5-day delay, 4 with a 6-day delay, 3 with a 7-day delay, 2 with a 9-day delay, and one each with an 11-, 24-, and 40-day delay in immobilization. Definitive treatment consisted of closed reduction or external pin fixation and antibiotics if the fractures were compounded. There were teeth in the line of fracture in 18 fractures. The teeth were retained in the line of fracture in 11 instances and removed in 7 instances. All patients were judged to be compliant with fixation and/or diet and antibiotics. Chronic suppurative osteomyelitis occurred at three fracture sites in three' different patients. GROUP

3: OPEN REDUCTION-EARLY IMMOBILIZATION

There were 43 patients with 75 fractures in this group. Twenty were simple and 55 were compound fractures. The time from injury to immobilization was less than 72 hours. Definitive treatment consisted of open reduction and maxillomandibular immobilization in three simple and 47 compound fractures. There were 25 concomitant fractures treated by closed reduction only. The time from trauma to open reduction ranged from 1 to 10 days, the average being 5 days. There were teeth in the line of fracture in 55 fractures. The teeth were retained in the line of fracture in 28 instances and removed in 27 instances. All patients were judged to be compliant with fixation and/or diet and prescribed antibiotics. There was infection of the bone in one case at one fracture site. GROUP

4:

OPEN REDUCTION-DELAYED IMMOBILIZATION

There were three patients with six fractures; four were simple fractures and two were compound frac-

tures. The time from injury to immobilization was greater than 72 hours, ranging from 4 to 7 days, the average being 5.3 days. There were three concomitant fractures treated by closed reduction. Definitive treatment consisted of three open reductions on two simple fractures and one compound fracture. All patients were judged to be compliant with fixation and/or diet and prescribed antibiotics. There was one case of chronic suppurative osteomyelitis at a compound fracture site, where an open reduction had been performed. GROUP

5: NONCOMPLIANT PATIENTS

There were four patients with seven fractures; one was a simple fracture and six were compound fractures. The time from injury to immobilization was less than 72 hours. Definitive treatment consisted of closed reduction at four fracture sites and open reduction at three fracture sites. There were teeth in the line of fracture in six fractures, all of which were retained. All patients were judged to be noncompliant with their fixation, diet, and antibiotics. Chronic suppurative osteomyelitis was diagnosed in four patients in four fracture sites. Two bone infections were post-closed reduction and two were post-open reduction. Results

The following variables were analyzed statistically in regard to being factors contributing to infection (P < .05): 1) location of fracture, 2) type of fracture (simple vs compound), 3) age of patient, 4) disposition of teeth (extracted vs retained), 5) method of treatment (open vs closed), 6) time of closed reduction (in those cases that were subsequently treated by open reduction). Of the exact Fisher probability tests performed, only type of fracture (P < .01) and time to closed reduction (P < .(05) were statistically significant. Discussion

The literature contains a number of reports in which the treatment of mandibular fractures has been both retrospectively and prospectively studied to assess the importance of various factors in the incidence of complications. Conflicting opinions exist regarding the importance of the disposition of teeth in the line of fracture. Bradley, in 1965, recommended that all teeth be removed from the line of'fracture.? Schneider and Stern, in 1971, reviewed a series of 199 fractures in which teeth were retained and noted that 5% developed posttreatment infections.!" They recommended that teeth can be

MAL.QNEY ET AL

selcctively retained at a fracture site when appropriate reductio~ a.nd fixation are achieved and antibiotics are administered, We recognize that any analysis of the disposition of tecth in the line of fracture is, by its nature, biased. Existing reports, including our own review, are not controlled studies wherein teeth in a fracture site were alternatively extracted or retained. The obvious situation is that when there is extensive damage to the teeth and adjacent soft tissue and bone, teeth tend to be extracted, creating a probable bias in the result. In this study, there was a total of 133 instances with teeth present in the line offracture. Of the 124 fracture sites that healed without bone infection, teeth were retained in 83 instances and extracted in 41 cases. A further breakdown of the data shows that of the III fracture sites treated by closed reduction with early immobilization in compliant patients, 58 had teeth in the line of fracture . Teeth were extracted in 6 instances and retained in 52 cases. All fractures healed without complication. Of the 50 open reductions with early immobilization in compliant patients (group 2) 47 had teeth in the line of fracture. Teeth were extracted in 27 instances (20 of the 27 were located in the angle region) and teeth were retained in 20 instances (5 were in the angle region). One case of chronic suppurative osteomyelitis developed where tooth no . 30 was avulsed at the time of injury. Teeth were present or retained in eight of the nine patients who were admitted with or laterdeveloped chronic suppurative osteomyelitis. This might appear to implicate retained teeth as the cause of the infection. However, a more detailed analysis of these patients revealed that two patients with 7- and 40-day-old fractures, respectively, were admitted with a diagnosis of chronic suppurative osteomyelitis and a third patient had a 6-day-old fracture (infected) at the time of admission. Four other patients were noncompliant with fixation and diet. This leaves one case of chronic suppurative osteomyelitis following an open reduction when tooth no. 30 was avulsed and a second case of chronic suppurative osteomyelitis in a case of delayed treatment with an open reduction where tooth no. 30 was retained. We believe that the significance of a tooth in the line of fracture is that its presence makes the fracture a compound fracture and thus provides a conduit for the introduction of bacteria into the fracture site. Our data show that when a fracture is immobilized early in patients compliant with fixation, diet, and prescribed antibiotics , neither the retention or the extraction of teeth in the line of fracture

701 is a statistically significant factor in causing chronic suppurative osteomyelitis. In 1976, Larson and Neilson advocated the early treatment offracture patients and reported a clinical infection rate of 0.4% in 220 compliant patients with mandibular fractures." In 1978 Neal et al reported their impression that the incidence of complications increased when there was a delay in the treatment of mandibular fractures ." However, in a report from the same group in 1979, Wagner et al analyzed the outcome in 100 consecutive cases of extraoral open reduction of the mandible and concluded that "operative delay did not reliably predict probability of complications.r'" These authors observed that "infected fractures requiring a sequestrectomy predominantly occurred in the angle region when teeth were removed from the site in conjunction with open reduction." James et al felt that while a delay in treatment may be a factor in complications, "there does seem to be a slight margin of safety. ,,5 In 1966, Kerr reported on 13 infections in mandibular fractures and observed that the great majority of infections occurred in fractures treated comparatively early." He further noted that "providing the patients are under antibiotic cover, reasonable delay in the treatment of the fracture wiII not materially add to the risk of infection. " This report did not define an exact time protocol to quality as early treatment; however all 13 infected fractures had delay of 3 or more days from the time of injury to immobilization. In 1952 Edgerton and Hill II reported a series of 424 mandibular fractures and made two very astute observations: "Fractures seen within the first 48 hours are classified as "fresh fractures. Such fractures of the angle involving the last molar tooth in which definite displacement of the fracture has occurred are now treated by removal of the tooth and external open reduction with intraosseous wiring." And, later in the report "even with the aid of chemotherapy we have hesitated to use open reduction on a fracture that has been both exposed to invasion by organisms of the oral cavity and without immobilization for several days." A legitimate question is, at what point has the infection within the medullary bone progressed to thrombophlebitis and increased risk of progression to a fully developed chronic suppurative osteomyelitis when there has been a delay in immobilization? We assume this progression would vary from patient to patient ; however, our data show that in group 2 all patients treated within 5 days of injury with closed reduction or external pin fixation and antibiotic therapy healed without complications. Indeed, 27 of the 28 patients admitted without obvious

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DISCUSSION

chronic suppurative osteomyelitis in group 2 treated by this method healed without developing chronic suppurative osteomyelitis. However, based on our experience of many years, coupled with our understanding of the pathology involved, we are reluctant to perform open reductions on fractures where immobilization has been delayed more than 72 hours. Thus, it is not surprising that our group 4 contained only three patients. As outlined in our list of principles, when an open reduction is absolutely necessary, and when immobilization has been delayed, we first treat the patient by closed reduction and/or external pin fixation together with IV antibiotics for a period of 10 to 21 days to resolve the bone infection before proceeding to an open reduction with intraosseous fixation. In Mowlem's classic article he theorized that the normalcy of blood supply is the determining factor in the development of osteomyelitis of the jaws.P We feel that when there has been a delay in treatment of compound fractures, the infection of the spongiosa eventually compromises the blood supply, and as one performs an open reduction and strips the periosteum at the fracture site, it is not surprising that these patients are particularly prone to progress to a chronic suppurative osteomyelitis. In our study of 204 fractures, 9 instances of suppurative osteomyelitis were observed. This represents an infection rate of 4.4%, which is comparable with other reports. These figures include two patients with old, untreated, compound fractures who were admitted with a diagnosis of chronic suppurative osteomyelitis and four other patients who were not compliant with treatment. Focusing only on the compliant patients immobilized within 72 hours of injury, there was a 0% incidence of chronic suppurative osteomyelitis in 111 fractures treated by closed reduction (86 fractures in group 1 and 25 fractures in group 3). Furthermore, of the 50 open reductions performed on compliant patients immo-

bilized within 72 hours on injury (group 3), there was one case of chronic suppurative osteomyelitis, representing an infection rate of 2%. Thus, of the total of 161 fractures treated by closed and/or open reduction with early immobilization in compliant patients, the incidence of chronic suppurative osteomyelitis was 0.6%. The low incidence of chronic suppurative osteomyelitis secondary to the treatment of mandibular fractures supports our principles that stress the early immobilization of compound fractures. The crucial issue is to identify those factors that increase the possible occurrence of chronic suppurative osteomyelitis and to understand why these factors predispose to the development of infection. We feel that early immobilization is the sine qua non in the treatment of compound mandibular fractures. References I. Chuong R, Donoff RB, Guralnick WC: A retrospective analysis of 327 mandibular fractures. J Oral Maxillofac Surg 41:305, 1983 2. Davidson TI\I, Bone RC, Nahum AM: Mandibular fracture complications. Arch Otolaryngol 102:627, 1976 3. Kerr NW: Some observations on infections in maxillofacial fractures. Br J Oral Surg 4:132, 1966 4. Krueger G: Textbook of Oral Surgery (ed 5). St Louis, MO, Mosby, 1979, p 354 5. James R, Frederickson C, Kent NJ: Prospective study of mandibular fractures. J Oral Surg 39:275, 1981 6. Larsen 00, Nielsen A: Mandibular fractures. Scand J Plast Reconstr Surg 10:219, 1976 7. Neal DC, Wagner WF, Alpert B: Morbidity associated with teeth in the line of mandibular fractures. J Oral Surg 36:859, 1978 8. Wagner WF, Neal DC, Alpert B: Morbidiy associated with extraoal open reduction of mandibular fractures. J Oral Surg 37:97, 1979 9. Bradley RL: Treatment of fractured mandible. Am Surg 31:289, 1965 10. Schneider SS, Stern M: Teeth in the Line of Mandibular Fracture. J Oral Surg 29:107, 1971 II. Edgerton MT, Hill E: Fractures of the mandible. Surgery 31:933, 1952 12. Mowlem R: Osteomyelitis of the jaw. Proc R Soc Med 38:452, 1945

J Oral Maxillofac Surg 49;702·703,1991

Discussion Early Immobilization of Mandibular Fractures: A Retrospective Study

Brian Alpert, DDS University of Louisville School of Dentistry, Louisville, KY

Open mandibular fractures have always possessed the potential for significant morbidity. One of the most hor-

rendous complications is osteomyelitis of the fracture site leading to long-term drainage and nonunion. Fortunately, it seldom occurs with modern treatment. Surgeons over the years have advocated various treatment protocols in an attempt to minimize complications. Removal of teeth from the fracture line, retention of teeth, various antibiotic regimens, closed management, rigid fixation, and early treatment have all been suggested. Some authors