Comminuted Fractures of the Radial Head COMPARISON OF RESECTION AND INTERNAL FIXATION

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1 76 COPYRIGHT 2005 BY THE JOURNAL OF BONE AND JOINT SURGERY, INCORPORATED Comminuted Fractures of the Radial Head COMPARISON OF RESECTION AND INTERNAL FIXATION BY MASAYOSHI IKEDA, MD, PHD, KAZUHIRO SUGIYAMA, MD, CHONTE KANG, MD, TOMONORI TAKAGAKI, MD, AND YOSHINORI OKA, MD, PHD Investigation performed at the Department of Orthopaedic Surgery, Tokai University Oiso Hospital, Kanagawa, Japan Background: Satisfactory internal fixation of comminuted radial head fractures is often difficult to achieve, and radial head resection has been the accepted treatment. In this study, we compared the results of radial head resection with those of open reduction and internal fixation in patients with a comminuted radial head fracture. Methods: Twenty-eight patients with a Mason type-iii radial head fracture (some with associated injuries) were enrolled in the study. Fifteen patients underwent radial head resection as the initial treatment (Group I), and thirteen patients underwent open reduction and internal fixation (Group II). The age at the operation averaged 41.1 and 38.2 years, respectively, and the duration of follow-up averaged ten and three years, respectively. The outcomes were assessed on the basis of pain, motion, radiographic findings, and strength measured with Cybex testing. The overall outcome was rated with the functional rating score described by Broberg and Morrey and with the American Shoulder and Elbow Surgeons Elbow Assessment Form. Results: Elbow motion averaged 15.5 (extension loss) to (flexion) in Group I and 7.1 to in Group II. The carrying angle and ulnar variance averaged 8.2 and 1.9 mm in Group I and 1.5 and 0.5 mm in Group II. Compared with Group II, Group I had a loss of strength in extension, pronation, and supination (p < 0.01). The Broberg and Morrey functional rating score averaged 81.4 points in Group I and 90.7 points in Group II (p = ). The score on the American Shoulder and Elbow Surgeons Elbow Assessment Form averaged 87.3 points in Group I and 94.6 points in Group II (p = ). Conclusions: The patients in whom the comminuted radial head fracture was treated with open reduction and internal fixation had satisfactory joint motion, with greater strength and better function than the patients who had undergone radial head resection. These results support a recommendation for open reduction and internal fixation in the treatment of this fracture. Level of Evidence: Therapeutic study, Level III. See Instructions to Authors for a complete description of levels of evidence. The treatment of displaced comminuted fractures of the radial head is controversial, with conflicting evidence to support either resection or open reduction and internal fixation 1-5. It is difficult to achieve satisfactory open reduction and internal fixation of a fracture that is comminuted and severely displaced. Improper internal fixation interferes with the smooth congruity of the proximal radioulnar articulation, and this limits joint motion, causes pain, and may lead to posttraumatic osteoarthrosis of adjacent joints. Therefore, radial head resection has been a valid therapeutic option, with reports of good long-term functional outcomes However, delayed complications, including pain, joint instability, proximal radial translation, decreased strength, osteoarthrosis, and cubitus valgus, have also been reported after radial head resection Radial head resection in patients with a severely comminuted radial head fracture, which often is associated with ligament disruption, may produce an extremely unstable elbow. Prior to July 1996, we performed radial head resection as the primary treatment for comminuted radial head fractures. After July 1996, we have performed internal fixation with small implants such as mini-plates or Herbert screws whenever possible. Thus, we were able to study two groups of patients: those who underwent radial head resection and those who underwent internal fixation for a similar type of comminuted fracture of the radial head. The purpose of this study was to evaluate and compare the outcomes in those two groups to determine the better method of treatment of comminuted radial head fractures.

2 77 Fig. 1 Mason type-iii radial head fracture patterns. A: A fracture of the entire radial neck, with the head completely displaced from the shaft. B: An articular fracture involving the entire head, which consists of more than two large fragments. Each fragment is completely displaced from the shaft. C: A fracture with a tilted and impacted articular segment, which must be reduced, and some articular fragments displaced from the shaft. Materials and Methods etween April 1984 and March 2001, we performed opera- on thirty-five consecutive patients with a commi- Btions nuted and displaced radial head fracture. All fractures were classified as type III according to the Mason 6 classification system. Some patients had an associated elbow dislocation, ligament injury, coronoid fracture, or Monteggia lesion (the so-called Mason type-iv variations) 3. Radial head resection was performed prior to July 1996 by two of us (M.I. and Y.O.), and open reduction and internal fixation was performed after July 1996 by one of us (M.I.). Two patients underwent prosthetic replacement of the radial head after July 1996 and were excluded from this study. Five patients who had undergone radial head resection were lost to follow-up, and the remaining twenty-eight patients were included in the study. Eighteen patients sustained the injury from a fall on the outstretched hand, and ten patients sustained the injury in a motor-vehicle accident. Our institutional review board approved the retrospective review, and the physical and radiographic examinations, including the assessment protocol, were carried out after the patients gave informed consent to participate in the study. Group I: Radial Head Resection Group I included fifteen patients (eleven men and four women) who had undergone primary radial head resection. Their average age at the time of the operation was 41.1 years (range, twenty-five to seventy years). There were nine Mason type-iii fractures and six Mason type-iv variations. Four patients had a simple fracture of the entire radial neck with the head completely displaced from the shaft (Fig. 1, A), seven had an articular fracture of the entire head consisting of more than two large displaced fragments (Fig. 1, B), and four had a fracture with an impacted articular fragment and small, comminuted, completely displaced fragments (Fig 1, C). Three patients who had a Mason type-iv variation with a posterior elbow dislocation initially underwent manipulative reduction and immobilization in a plaster splint. The average time from the injury to the operation was nine days (range, one to fourteen days). Radial head resection was carried out through a lateral or posterolateral approach, with the head removed at the level of the annular ligament. The lateral collateral ligament was repaired with number-1 nonabsorbable braided sutures or an anchoring system (Mitek GII Quick Anchor Plus; Ethicon, Johnson and Johnson, Westwood, Massachusetts) at joint closure. Four patients had a coronoid fracture. According to the Regan-Morrey 22 classification system, three of these fractures were type I (simple avulsion of the tip of the process), and one was type II (a single fracture involving approximately 50% of the process). The coronoid fracture fragment was removed in the three patients with a type-i fracture, and the type-ii fracture was internally fixed. A Monteggia lesion was present in one patient who had a posteriorly angulated fracture of the proximal third of the ulna with a posterior dislocation of the fractured radial head. The fracture of the ulna was internally fixed when the radial head was resected. In five patients with a medial collateral ligament injury, the ligament was repaired with number-1 nonabsorbable braided sutures or an anchoring system. The average period of immobilization after the radial head resections was eight days (range, one to fourteen days). Active forearm rotation exercises were initiated with the arm in a sling and the elbow at a right angle. Active range-ofmotion exercises of the elbow were started two weeks after the operation. The five patients with a repaired medial collateral ligament wore a long arm cylinder cast instead of a sling to keep the elbow at a right angle in order to allow forearm rotation. The cast was changed to a hinged brace, and active elbow movement was started two weeks postoperatively. The brace was worn continuously for four weeks. The average period of postoperative follow-up was ten years (range, three to eighteen years).

3 78 Group II: Open Reduction and Internal Fixation Group II included thirteen patients (seven men and six women) who underwent open reduction and internal fixation. The average age at the time of the operation was 38.2 years (range, twenty to seventy-one years). There were three Mason type-iii fractures and ten Mason type-iv variations. Nine patients had an articular fracture of the entire head. Three of those fractures consisted of two large fragments, and the other six consisted of more than three large fragments with or without marginal fragments. Four fractures included large impacted articular fragments and two or three small fragments. Two patients who had a Mason type-iv variation with a posterior elbow dislocation initially underwent manipulative closed reduction. A Mason type-iii fracture, classified as a type-ii open fracture according to the criteria of Gustilo et al. 23, was treated initially with débridement and irrigation and the wound was closed primarily. The average time from the injury to the operation was twelve days (range, eight to sixteen days). All fractures of the radial head were internally fixed with use of low-profile mini-plates 24 (Stryker Leibinger, Freiburg, Germany) and/or Herbert screws (Zimmer, Warsaw, Indiana) (Figs. 2-A through 2-F). The radial head fracture was accessed through an approach similar to that used for the radial head resections. When the medial collateral ligament was torn, it was anchored with a number-1 nonabsorbable braided suture or an anchoring system prior to fracture reduction. The anchor suture was tied after fracture fixation. The fracture was reduced and was held with small forceps or tenacular clamps, or it was temporarily fixed with 1.0-mm Kirschner wires. The low-profile mini-plate used in this series was T-shaped with a 0.55-mm profile height and a 1.7-mm screw diameter. In eleven patients, cancellous bone chips or graft blocks, obtained from the ipsilateral olecranon in three patients and from the iliac crest in eight, were placed between the radial head and neck or in other areas of bone deficit of the reduction. The annular ligament was sutured with number-1 nonabsorbable braided sutures, and the lateral collateral ligament was repaired with number-1 nonabsorbable braided sutures or an anchoring system subsequently. Eight fractures were fixed with low-profile mini-plates, three fractures were fixed with Herbert screws, and two fractures were fixed with a combination of the two. Bone-grafting was performed in eleven fractures. The medial collateral ligament was repaired in seven patients who had the Mason type- IV variation, and the lateral collateral ligament was repaired in four. A type-i fracture of the coronoid tip was present and the fragment was removed in two patients with a Mason type-iv variation. One patient had a small avulsion fracture of the olecranon, and the triceps tendon was repaired at its insertion. An osteochondral fracture of the capitellum in a patient with a Mason type-iv variation was fixed with a bone peg graft obtained from the olecranon crest. Forearm rotation exercises, with the extremity in a long arm cylinder cast and the elbow at a right angle, were started two days (range, one to four days) after the surgery. The cast was worn for two weeks, after which it was changed to a hinged brace and active elbow movement was started. The brace was worn continuously for four weeks. Of the ten patients in whom the fracture was fixed with low-profile miniplates, nine had the plates removed after five to seven months to prevent deterioration of the proximal radioulnar cartilage. One patient with a Mason type-iv variation refused to have the plates removed. The follow-up period after the initial operation averaged three years (range, two to four years). Outcome Measures and Statistical Methods The outcome assessment included a questionnaire inquiring about pain, impairment, and elbow disability. The responses were incorporated into the Broberg and Morrey functional rating score 9 and the American Shoulder and Elbow Surgeons Elbow Assessment Form 25. Physical assessment included measurement of the ranges of motion of the elbow and forearm and of grip strength. A standard long-limb goniometer was used to measure range of motion. Flexion and extension of the elbow were measured with the forearm in neutral rotation, and rotation of the forearm was measured with the elbow at a right angle. Bilateral anteroposterior and lateral radiographs of the elbow were made to assess osseous union, congruity, Fig. 2-A Anteroposterior radiograph demonstrating a Mason type-iii radial head fracture.

4 79 Fig. 2-B Intraoperative photograph showing a Mason type-iii fracture consisting of two large fragments and a marginal fragment. and posttraumatic osteoarthrosis. Bilateral anteroposterior radiographs of the wrist and elbow were made in supination to measure the carrying angle and ulnar variance. Osteoarthrosis in the elbow was classified, according to the Broberg and Morrey system 9, as grade zero (absent; normal elbow), grade one (mild, with slight joint space narrowing or minimum osteophyte formation), grade two (moderate, with moderate joint space narrowing or moderate osteophyte formation), or grade three (severe, with severe degenerative change and joint destruction). The strength of flexion and extension of the elbow and of pronation and supination of the forearm was measured with the Cybex 770-NORM (Cybex International, Ronkonkoma, New York). The peak torques of flexion and extension of the elbow and pronation and supination of the forearm were measured at 60 /sec and 30 /sec, respectively. Twenty normal subjects were studied to determine the normal variation in grip strength and the results of Cybex testing between dominant and nondominant sides, as described by Morrey et al. 12. The ratio of the nondominant to the dominant side was 0.87 for grip strength, 0.89 for extension, 0.91 for flexion, 0.78 for pronation, and 0.72 for supination. These values were used to calculate and normalize the loss of strength on the dominant or nondominant extremity independently. The outcome was rated with the Broberg and Morrey functional rating score 9 and the American Shoulder and Elbow Surgeons Elbow Assessment Form 25. Standard statistical methods were employed. Descriptive statistics, including means and standard deviations, were calculated and Groups I and II were compared. The Fig. 2-C Fig. 2-D Fixation was achieved with two Herbert screws and two low-profile mini-plates.

5 80 Pain Visual-analog-scale scores in the American Shoulder and Elbow Surgeons Elbow Assessment Form were used to compare the patients perception of pain, with 25 points representing the best possible score. The average score was 19.3 points (range, 12 to 25 points) in Group I and 22.4 points (range, 17 to 25 points) in Group II (p = ) (Table I). Five patients in Group I and one in Group II had mild pain in the elbow with strenuous use that required forearm rotation. Three patients in Group I complained of a dull ache and numbness along the ulnar aspect of the forearm. Motion Flexion contracture of the elbow averaged 15.5 (range, 5 to 46 ) in Group I compared with 7.1 (range, 0 to 23 ) in Group II (p = ). The ranges of motion in the two groups were similar. Flexion of the elbow averaged (range, 111 to 142 ) in Group I compared with (range, 116 to 143 ) in Group II (p = ). Pronation of the forearm averaged 74.8 (range, 32 to 84 ) in Group I compared with 73.3 (range, 63 to 81 ) in Group II (p = ). Supination of the forearm averaged 82.1 (range, 69 to 89 ) in Group I compared with 85.3 (range, 75 to 90 ) in Group II (p = ). Strength The average loss of grip strength was 15.0% (range, 2% to 34%) in Group I compared with 10.4% (range, 0% to 24%) in Group II (p = ). Group I lost, on the average, 28.6% (range, 6.5% to 40.0%) of strength in extension, 17.9% (range, 6.2% to 35.0%) in flexion, 26.4% (range, 7.1% to 54.7%) in Fig. 2-E Postoperative anteroposterior radiograph. Mann-Whitney U test was used to evaluate the significance of intergroup differences, and a p value of <0.01 was considered significant. Results ll fractures in Group II had osseous union. When the A plates were removed after five to seven months in nine patients, they were covered by synovial tissue and they did not seem to interfere with the function of the proximal radioulnar joint. One patient who had no symptoms refused to have the plates removed. One patient with an open Mason type-iii fracture had a delayed union, and it took eleven months until osseous union was evident radiographically. Fig. 2-F The plates were removed five months after internal fixation. One Herbert screw was removed and the other was left in situ.

6 81 TABLE I Pain Scores and Functional Assessment Scores Measure* Group I Group II P Value VAS pain score of ASES (points) 19.3 ± ± Broberg and Morrey functional 81.4 ± ± rating score (points) ASES score (points) 87.3 ± ± *Pain was assessed with the visual-analog-scale (VAS) of the American Shoulder and Elbow Surgeons Elbow Assessment Form (ASES) 25, with 25 points representing the best possible score. Function was assessed with the Broberg and Morrey functional rating score 9 and the ASES score. The values are given as the mean and standard deviation. pronation, and 38.3% (range, 14.3% to 55.5%) in supination. Group II lost an average of 11.8% (range, 2.3% to 29.7%) of strength in extension, 21.3% (range, 5.5% to 37.5%) in flexion, 13.6% (range, 0% to 42.3%) in pronation, and 7.7% (range, 0% to 30.1%) in supination. Loss of strength in extension (p = ), pronation (p = ), and supination (p < ) was greater in Group I than it was in Group II (Fig. 3). There was no significant difference between the groups with regard to strength in flexion (p = ). Radiographic Assessment In comparison with the value for the contralateral limb, the average increase in the carrying angle was 8.2 (range, 0 to 20 ) in Group I and 1.5 (range, 0 to 5 ) in Group II (p < ) (Table II). The average increase in ulnar variance was 1.9 mm (range, 0 to 5 mm) in Group I and 0.5 mm (range, 2 to 3 mm) in Group II (p = ) (Table II). Degenerative changes in Group I were grade zero in four elbows, grade one in six, and grade two in five (Figs. 4-A and 4-B). Degenerative changes in Group II were grade zero in seven elbows and grade one in six. Varying degrees of osteoarthrosis were recognized in Group I but not in Group II. Functional Assessment The Broberg and Morrey functional rating score averaged 81.4 points (range, 57 to 92 points) in Group I and 90.7 points (range, 73 to 100 points) in Group II (p = ) (Table I). According to this scoring system, the result was rated as good for nine patients, fair for five, and poor for one in Group I. The result was rated as excellent for three patients, good for nine, and fair for one in Group II. The average score according to the American Shoulder and Elbow Surgeons Elbow Assessment Form was 87.3 points (range, 70 to 97 points) in Group I and 94.6 points (range, 77 to 100 points) in Group II (p = ) (Table I). Discussion cceptable long-term functional outcomes have been reported after primary or delayed radial head resection A performed as a salvage operation for Mason type-iii fractures 6,7,9-11,26. Radial head resection has been associated with long-term complications, including wrist and forearm pain, increased valgus elbow deformity, degenerative osteoarthrosis, and decreased strength. However, these complications are not considered serious as long as joint mobility is preserved 6-10,12,19. Many authors 10,12-16,18,20 have reported a 2 to 3-mm increase in proximal translation of the radius and an increase in ulnar variance after radial head resection. These changes can cause wrist, forearm, and elbow pain with resultant ulnar Fig. 3 Loss of strength, expressed as a percentage of the strength on the uninjured side, in elbow extension and flexion and forearm pronation and supination. The values are given as the mean and standard deviation, and the difference between the dominant and nondominant sides has been normalized.

7 COMMINUTED FR ACTURES O F T H E R A D I A L HE A D THE JOUR NAL OF BONE & JOINT SURGER Y JBJS.ORG VO L U M E 87-A N U M B E R 1 J A N U A R Y 2005 TABLE II Radiographic Assessment of Valgus Deformity of the Elbow and Proximal Translation of the Radius Measure Group I* Group II* P Value Increase in carrying angle (deg) 8.2 ± ± 1.8 < Increase in ulnar variance (mm) 1.9 ± ± *The values are given as the mean and standard deviation. Compared with the value on the contralateral side. abutment, subluxation of the distal radioulnar joint, or stretching of the interosseous membrane14,16,18. A 5 to 20 increase in the carrying angle of the elbow has also been reported10,13, This valgus elbow deformity can result in the development of ulnar nerve symptoms. Although the conditions under which strength was measured were not uniformly normalized in previous studies, loss of strength in elbow flexion and extension and in forearm rotation may approach 30%8,9,12,18,27. Our study demonstrated less elbow extension and forearm rotation strength after radial head resection than after open reduction and internal fixation. The main mechanism for loss of strength is probably related to the decreased proximal support of the radius, which normally acts as a loadbearing fulcrum to transmit forces across the radiocapitellar articulation. Other contributing factors may include restricted joint mobility, valgus instability, functional discomfort, and psychologic factors. The importance of the radial head and radiocapitellar contact has been noted both clinically and experimentally, especially after radial head fractures associated with ligament injuries The most common cause of failure of open reduction and internal fixation has been the inability to achieve rigid internal fixation5,30. The advent of the Herbert screw and, more recently, the mini-plate system has created the possibility of reducing and internally fixing radial head fractures that previously would have required resection24,28-31, Although repair of severely comminuted fractures is technically demanding and not all radial head fractures are amenable to open reduction and internal fixation, our results justify an effort to preserve the radial head. Fig. 4-B Anteroposterior (Fig. 4-A) and lateral (Fig. 4-B) radiographs of the elbow, showing moderate degenerative changes thirteen years after radial head resection. There is severe osteophyte formation at the coronoid and olecranon processes. Fig. 4-A

8 83 Ideally, all comminuted radial head fractures should be treated with internal fixation with small implants. Since we started using small implants for internal fixation of comminuted fractures, we have fixed all but two successfully. The two patients in whom the fracture was not fixed would not accept the bone-grafting and the postoperative protocol for internal fixation, including plate removal; they underwent prosthetic radial head replacement primarily without an attempt at open reduction and internal fixation. While there was no bias in this study with regard to patient selection according to fracture severity or technical difficulty, the study did have several limitations. First, it was a longitudinal study comparing a cohort of patients who had undergone radial head resection prior to July 1996 with a group that had been treated more recently with open reduction and internal fixation. Thus, there is an obvious difference in the duration of follow-up between the two groups (ten years in Group I compared with three years in Group II), although all patients were followed for a minimum of two years. This discrepancy may have had a substantial effect on the reported prevalence of degenerative elbow changes, which was greater in the patients who had had the radial head resection. Second, we attribute our good results to meticulous surgical technique, especially the use of low-profile mini-plates and bone-grafting. A third limitation of the study is the difference in postoperative protocol between the groups, but the final ranges of motion of the two groups were similar and the follow-up period was sufficient to evaluate strength. Although the average ages of the patients in the two groups were similar at the time of the operation, the patients in Group I were, on the average, older than those in Group II at the final evaluation. Despite these limitations, we concluded that open reduction and internal fixation results in satisfactory joint mobility and provides better strength and a better overall functional outcome than does radial head resection. Therefore, open reduction and internal fixation should be pursued in the treatment of comminuted fractures of the radial head unless extenuating factors, such as poor general health or advanced age, prevent the patient from participating in the postoperative rehabilitation protocol. Masayoshi Ikeda, MD, PhD Kazuhiro Sugiyama, MD Chonte Kang, MD Tomonori Takagaki, MD Yoshinori Oka, MD, PhD Department of Orthopaedic Surgery, Tokai University Oiso Hospital, 21-1 Gakkyo, Oiso, Naka-gun Kanagawa, , Japan. address for M. Ikeda: zenryo@oiso.u-tokai.ac.jp The authors did not receive grants or outside funding in support of their research or preparation of this manuscript. 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