Percutaneous pinning after closed reduction of supracondylar

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1 ORIGINAL ARTICLE Complications After Pinning of Supracondylar Distal Humerus Fractures Ravi K. Bashyal, MD,*w z Jennifer Y. Chu, MD,* Perry L. Schoenecker, MD,*w z Matthew B. Dobbs, MD,*w z Scott J. Luhmann, MD,*w z and J. Eric Gordon, MD*w z Background: Supracondylar distal humerus fractures are one of the most common skeletal injuries in children. The current treatment of choice in North America is closed reduction and percutaneous pin fixation. Often surgeons leave the pins exposed beneath a cast but outside the skin. Great variation exists with respect to preoperative skin preparation, and perioperative antibiotic administration. Few data exist regarding the rate of infection and other complications. The purpose of this study is to review a large series of children to evaluate the rate of infection and other complications. Methods: A retrospective review was carried out of all patients treated at our institution over an 11-year period. A total of 622 patients were identified that were followed for a minimum of 2 weeks after pin removal. Seventeen patients had flexion-type fractures, 294 had type II fractures, and 311 had type III fractures. Seventy-four fractures (11.9%) had preoperative nerve deficits with anterior interosseous palsies being the most common (33 fractures, 5.3%). Preoperative antibiotics were given to 163 patients (26.2%). Spray and towel draping were used in 362 patients, paint and towel draping were used in 65 patients, alcohol paint and towel draping were used in 146 patients, and a full preparation and draping were used in 13 patients. The pins were left exposed under the cast in 591 fractures (95%), and buried beneath the skin in 31 fractures (5.0%). A medial pin was placed in 311 fractures with a small incision made to aid placement in 18 of these cases. Results: The most common complication was pin migration necessitating unexpected return to the operating room for pin removal in 11 patients (1.8%). One patient developed a deep infection with septic arthritis and osteomyelitis (0.2%). Five additional patients had superficial skin infections and were treated with oral antibiotics for a total infection rate of 6 of 622 patients (1.0%). One patient ultimately had a malunion and 4 others returned to the operating room for repeat reduction and pinning. Three patients developed compartment syndromes. From the *Department of Orthopaedic Surgery, Washington University School of Medicine; wst Louis Children s Hospital; and zst Louis Shriners Hospital, St Louis, MO. Study conducted at Washington University School of Medicine, St Louis Shriners Hospital for Children, and St Louis Children s Hospital, St Louis, MO. None of the authors received financial support for this study. Reprints: J. Eric Gordon, MD, 4S-60 St. Louis Children s Hospital, 1 Children s Place, St. Louis, MO address: Gordone@ wustl.edu. Copyright r 2009 by Lippincott Williams & Wilkins Ulnar nerve injury was rare with only 1 postoperative ulnar nerve injury occurring in 311 patients treated with a medial pin (0.3%). Conclusions: Closed reduction with percutaneous pinning is effective and has a low complication rate with a very low rate of infection even when simple betadine preparation and towel draping are used. Preoperative antibiotics seem to have little effect on infection rate. Level of Evidence: Level III retrospective comparative study. Key Words: supracondylar distal humerus fracture, complications, percutaneous pinning, infection rate, preoperative antibiotics, closed reduction (J Pediatr Orthop 2009;29: ) Percutaneous pinning after closed reduction of supracondylar distal humerus fractures is currently one of the most common procedures that the surgeon caring for children s fractures is called upon to perform Each surgeon must make a choice of what type of skin preparation to use and whether or not to administer antibiotics perioperatively. Furthermore, the surgeon must decide whether to leave the ends of the pins exposed outside the skin beneath the cast for easy removal or buried under the skin, necessitating a second procedure to remove the pins. There is a great variety in the techniques used by different surgeons. Most preferences are based on training or experience and few data exist to aid the surgeon in deciding between methods. At our institution, several different techniques of skin preparation have been used. These include a simple betadine spray and towel draping, using an image intensifier as a table; an alcohol wash of the extremity followed by betadine spray and towel draping, again using an undraped c-arm as the table; and a full betadine scrub and formal preparation followed by placement of an extremity drape and use of a draped image intensifier. In addition, there has been a great deal of variation in whether or not preoperative or postoperative antibiotics are given, with some patients receiving no antibiotic prophylaxis, some receiving only preoperative antibiotics, and some receiving preoperative and postoperative antibiotics. The purpose of this study was to evaluate the rate of infection in children with supracondylar distal humerus J Pediatr Orthop Volume 29, Number 7, October/November 2009

2 J Pediatr Orthop Volume 29, Number 7, October/November 2009 Supracondylar Complications fractures treated with closed reduction and pinning procedure with alternative methods of draping and antibiotic administration. METHODS After obtaining the approval of our institutional review board, we carried out a retrospective review of all patients with operatively treated displaced or angulated supracondylar distal humerus fractures in children at our institution between January 1, 1994 and December 31, Open fractures and fractures treated by open reduction were excluded. A total of 746 consecutive patients were identified who were treated with the closed reduction and percutaneous pinning procedure. Thirteen of these patients were excluded from the study because they were either lost to follow-up before pin removal or the pins were removed by outside physicians. Of the remaining 733 patients, 111 were excluded because they were last seen less than 2 weeks after pin removal (usually at the time of pin removal). All of these patients were doing well at the time of last follow-up, without evidence of infection or other complications. The remaining 622 patients (83.4% of the patients treated by closed reduction and percutaneous pinning) were followed for a minimum of 2 weeks after pin removal and comprised the study group. Charts were reviewed for patient demographics and details of operative care, including timing, the type of skin preparation and draping, preoperative and postoperative antibiotic administration, whether or not the pins were buried or left outside the skin, and intraoperative complications. Postoperative care, including the duration of immobilization and how long the pins were left in place, were also recorded. Finally, chart information regarding late complications, including evidence of infection or pin site problems was recorded. Surgical Technique Patients are usually evaluated in the emergency room after injury. Our practice has been to treat type 2 fractures semielectively at a convenient time within 24 hours of the fracture. Type 3 fractures are taken to the operating room as soon as possible. If preoperative antibiotics were administered, they were usually given on arrival in the operating room. One of 4 protocols was then followed, at the treating surgeon s discretion: a full betadine preparation with formal draping, alcohol wash followed by a betadine spray and towel draping, a betadine paint and towel draping, or a spray betadine preparation and towel draping. If a full preparation and draping procedure was to be performed, the reduction was performed after the preparation and draping. If an alcohol wash was performed, this was similarly performed before the reduction and the betadine spray procedure was carried out after the reduction. Betadine painting or betadine spray preparation was performed after the reduction. If a full preparation was performed, a radiolucent arm table was used. All other techniques used the image intensifier as a table for the elbow. The surgeon reduced the fracture with the aid of image intensification and it was held in a reduced position during the betadine paint or spray. Pin fixation was then performed with the aid of the image intensifier. If a medial pin was placed, 1 or 2 lateral pins were placed with the elbow in flexion and the elbow was then brought into an extended position, within no less than 45 degrees of extension to avoid ulnar nerve subluxation. 26 The nerve was then carefully palpated. If the nerve could not be identified, a small incision was made medially to ensure protection of the ulnar nerve. When the pin was placed blindly, careful attention was paid to the hand when the pin was inserted; if the hand was noted to twitch, the pin was withdrawn and the nerve position was reassessed before another attempt. In 31 of the 622 fractures, the pins were cut off beneath the skin. In the remainder, the pins were left outside the skin, sterilely dressed and a cast or splint was applied. Pins were kept beneath the cast and no routine pin site care was performed. The patient was subsequently discharged home. Most were seen 1 week postoperatively and radiographs were obtained in the cast. The dressings, splint or cast, were not removed at this time except in rare situations in which there was a clinical concern for infection. Pins were usually removed and radiographs obtained 3 weeks postoperatively. A simple bandage was placed over the pin sites and bathing was permitted immediately. Patients were then routinely seen 2 to 4 weeks after pin removal for follow-up. A total of 622 patients were available for review with a minimum of 2 weeks follow-up after pin removal. The mean follow-up was 40 weeks after pin removal (range, 2 to 619 wk). There were 319 boys and 303 girls. The left elbow was involved in 402 fractures and the right in 220 fractures. There were 17 flexion-type injuries and 605 extension-type fractures with 294 Gartland type 2 fractures and 311 Gartland type 3 injuries. 27 Neurologic deficits were noted preoperatively in 74 fractures (11.9%) (Table 1) including isolated anterior interosseous nerve injuries in 32; isolated radial nerve injuries in 20, isolated ulnar nerve injuries in 10, and isolated median nerve injuries in 8 patients. Four additional patients had injuries to multiple nerves with 1 patient each having combined radial and medial, radial and anterior interosseous, radial and ulnar, and radial, median and ulnar deficits. Four of the 10 ulnar nerve deficits occurred in 17 flexion-type injuries (24%). Sixty-six of the 74 nerve injuries occurred in type 3 fractures (21% of the 311 type 3 fractures). The supracondylar fracture was the only osseous injury to the extremity in 582 fractures (93.6%). The supracondylar TABLE 1. Neurologic Deficits Flexion (17) Type 2 (294) Type 3 (311) (622) Anterior interosseous 0 (0%) 2 (0.7%) 31 (10.0%) 33 (5.3%) Radial 0 (0%) 1 (0.3%) 23 (7.4%) 24 (3.9%) Median 0 (0%) 0 (0%) 10 (3.2%) 10 (1.6%) Ulnar 4 (24%) 2 (0.7%) 5 (1.6%) 11 (1.8%) 4 (24%) 5 (1.7%) 66 (21.2) 74 (11.9%) r 2009 Lippincott Williams & Wilkins 705

3 Bashyal et al J Pediatr Orthop Volume 29, Number 7, October/November 2009 TABLE 2. Skin Preparation and Antibiotic Use No Preoperative Preoperative Spray/towel Paint/towel Alcohol/spray/towel Full fracture was associated with a distal radius fracture in 13 cases, a distal radius and ulna fracture in 17 cases, a midshaft forearm fracture in 8 cases, a proximal humerus fracture in 1 case, and both a proximal humerus fracture and a distal radius fracture in 1 case. Preoperative intravenous antibiotics were used in 163 cases. The antibiotic was cefazolin in 160 cases, clindamycin in 2 cases, and vancomycin in 1 case. Of the 163 cases in which a preoperative antibiotic was used, 122 also received at least one dose of postoperative antibiotics (Table 2). Skin preparation was a full betadine preparation and draping in 13 cases, alcohol wash with betadine spray preparation and towel draping in 146 cases, betadine paint with towel draping in 101 cases, and betadine spray with towel draping in 362 cases (Table 2). The pin configuration used was 2 lateral pins in 266 fractures, 3 lateral pins in 42 fractures, 1 lateral and 1 medial pin in 76 fractures, and 2 lateral and 1 medial pin in 225 fractures. Thirteen fractures were treated with other pin configurations. The pins were buried beneath the skin in 31 fractures (5.0%), including 22 in which an alcohol wash, betadine spray, and towel drape were used, 2 in which a betadine paint and towel drape were performed, and 7 in which a betadine spray and towel drape were used. RESULTS All of the 622 fractures went on to union. There were a total of 32 complications (5.1%) (Table 3). Pin migration beneath the skin necessitating a return to the operating room to remove pins was the most common complication, occurring in 11 fractures (1.8%). Loss of reduction necessitating a return to the operating room for repinning occurred in 4 fractures (0.6%), with a single fracture healing with a cubitus varus deformity (0.2%) resulting in a total incidence of loss of reduction after pinning of 5 of 622 fractures (0.8%). A compartment syndrome occurred in 3 fractures (0.5%). In 2 fractures, the Kirschner wires broke off inside the humerus and were left in place. A single patient had an ulnar nerve injury after blind placement of a medial pin. A total of 311 fractures had at least 1 medial pin placed (2 of these fractures had 2 medial pins placed). Eighteen of the 311 were placed after a small incision had been made to localize the nerve; 293 fractures were treated with placement of a blind medial pin. The rate of ulnar nerve injury with the placement of a blind ulnar pin was 1 of 293 (0.3%). The overall rate of ulnar nerve injury for all medial pins was 1 of 311 (0.3%). Pin site problems occurred in a total of 10 fractures. Four of these involved granulation tissue forming at the pin sites necessitating treatment with silver nitrate as an outpatient procedure. Six patients developed infections associated with the pin sites (1.0%) (Table 4). Five patients had evidence of superficial infection and resolved after treatment with a 7 to 10-day course of oral antibiotics. A single patient developed septic arthritis of the elbow with associated osteomyelitis. This patient had not received preoperative antibiotics and surgery was performed after a betadine paint and towel drape. This infection was treated with surgical irrigation and debridement in addition to 6 weeks of intravenous antibiotics with subsequent resolution of the infection. Of the 6 total infections (Table 4), 1 (the deep infection) occurred in the betadine paint and towel drape group (1.0% rate within group); 2 occurred in the alcohol wash and betadine spray group (1.4% rate within the group), and 3 occurred in the betadine spray and towel drape group (1.1% rate within the group). With respect to antibiotic use, 2 infections (including the deep infection) occurred in patients who had received preoperative antibiotics (1.2% rate within group) and 4 infections occurred in patients who did not receive preoperative antibiotics (1.1% rate within group). There was no statistically significant correlation between the use of preoperative antibiotics or type of skin preparation and infection. TABLE 3. Complications Flexion Type Type 2 Type 3 None 15 (88%) (94.9%) Pin migration 1 (6%) 1 (0.3%) 9 (2.9%) 11 (1.8%) Ulnar nerve palsy 0 (0%) 0 (0%) 1 (0.3%) 1 (0.2%) Loss of reduction 0 (0%) 1 (0.3%) 3 (1.0%) 4 (0.6%) Malunion 0 (0%) 1 (0.3%) 0 (0%) 1 (0.2%) Granulation tissue 0 (0%) 1 (0.3%) 3 (1.0%) 4 (0.6%) Compartment syndrome 1 (6%) 0 (0%) 2 (0.7%) 3 (0.5%) Broken K-wire 0 (0%) 0 (0%) 2 (0.7%) 2 (0.3%) Superficial infection 0 (0%) 3 (1.0%) 2 (0.7%) 5 (0.8%) Osteomyelitis and septic arthritis 0 (0%) 0 (0%) 1 (0.3%) 1 (0.2%) complications 2 (12%) 7 (2.4%) 23 (7.4%) 32 (5.1%) r 2009 Lippincott Williams & Wilkins

4 J Pediatr Orthop Volume 29, Number 7, October/November 2009 Supracondylar Complications TABLE 4. Skin Preparation and Antibiotic Use in Patients With Infections No Preoperative Preoperative Spray/towel 2 (0.7%) 1 (1.0%) 3 (0.8%) Paint/towel 1 (1.5%) 0 (0.0%) 1 (1.0%) Alcohol/spray/towel 1 (0.9%) 1 (2.8%) 2 (1.4%) Full 0 (0.0%) 0 (0.0%) 0 (0.0%) 4 (0.9%) 2 (1.2%) 6 (1.0%) DISCUSSION Few data exist with regard to the incidence of infection associated with the semisterile conditions during which percutaneous pinning of supracondylar fractures is frequently performed. A single study by Iobst et al 6 described the results at a single institution and reported no infections in 304 cases. In our group of patients, the infection rate was quite low regardless of the specific preparation type that was used. In addition, no statistical difference was seen in the overall infection rate when preoperative antibiotics were administered. Overall, there was no statistically significant correlation between the use of preoperative antibiotics or type of skin preparation and infection. These data suggest that the commonly used technique of limited sterile preparation and towel draping is safe, and that the administration of perioperative antibiotics in routine cases is not indicated. The institution of these practices would result in a decrease in the costs associated with the treatment of these injuries. This report seems to be comparable to other series with an overall incidence of preoperative neurologic deficit of 11.9% in closed fractures, with most of the neurologic injuries occurring in flexion-type injuries (22% incidence) and type 3 fractures (21.2% incidence). As in other recent series, the anterior interosseous and radial nerves were the most frequently injured. As this series specifically excludes open fractures, the overall incidence in all fractures of this type is probably higher. Closed reduction and pinning of supracondylar distal humerus fractures is safe and effective in obtaining adequate osseous union with a low rate of complications. The most common complication experienced was migration of the pins with retraction beneath the skin. Loss of reduction with subsequent repinning or malunion occurred in only 5 patients. There has been a great deal of concern expressed in the literature with regard to the placement of medial pins and risk to the ulnar nerve. 16,36 40 A number of authors have advocated the placement of divergent lateral pins in type 3 fractures to obviate the need for a medial pin. 5,41 44 Our experience would seem to suggest that if the surgeon extends the elbow before medial pin insertion, 45 is willing to make an incision to identify the nerve, 7,46 and is willing to withdraw and reposition the pin if irritation of the ulnar nerve is noted on pin insertion, then a very low rate of ulnar nerve injury can be achieved. The overall low rate of complications in treating angulated or displaced supracondylar distal humerus fracture calls into question recent attempts to avoid operative treatment in these injuries. 47,48 Loss of reduction in patients with either type 2 or 3 fractures that are treated nonoperatively is 20% to 30%. This rate, in a group of patients that does not return promptly, can lead to malunion and subsequent need for osteotomy. This risk, compared with the relatively low risk of operative management, would suggest that operative intervention is warranted in most cases. CONCLUSIONS Limited preparation with towel draping in the treatment of supracondylar distal humerus fractures has a low complication rate and very low infection rate. There does not seem to be any advantage to full preparation and draping or preoperative antibiotics in patients with displaced supracondylar distal humerus fractures in children. REFERENCES 1. Gerardi JA, Houkom JA, Mack GR. Pediatric update #10. 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