Supracondylar Fractures



Supracondylar FracturesOf the Humerus in Children194310026924000Principles of ManagementKaye E. Wilkins, M.D.Professor, Orthopedics and PediatricsUniversity of Texas Health Science Center at San AntonioMail Code 7774 - 7703 Floyd Curl DriveSan Antonio, Texas 78229-3900drkwilkins@Supracondylar Fractures of the Humerus in ChildrenPrinciples of ManagementI. Incidence1. At what age do they most commonly occur?They peak at 7 years of age.(KA01).2. Why is the peak incidence at 7 years of age?When a child falls on its extended upper extremity those patients who demonstrate hyperextension (cubitus recurvatum) (CH01, NO99) of the elbow are more predisposed to have supracondylar fractures. Those children who do not have hyperextension of the elbow tend to sustain fractures of the radius and the ulna, usually in the distal portion.3. What other factor at this age contributes to the increased incidence of humeral fractures in the supracondylar area?Because of growth, this supracondylar area is composed of weak, remodeling, metaphyseal bone. The cortices are very thin.II. Mechanism of Injury4. What is the mechanism of injury for extension type supracondylar fractures? Hyperextension of the elbow joint and weakened metaphyses, fractures are common in this age group. When the child falls, they usually extend the non-dominated upper extremity to catch themselves.If they exhibit hyperextension, the olecranon is able to penetrate deeply to its fossa, which concentrates all the bending forces at the supracondylar area. Since at this age the supracondylar area is weakened metaphyseal bone, it resists the extension forces poorly and thus fails easily.The are three different stages of failure:1. Almost none or break in the anterior cortex;2. A partial break in the distal humerus but leaving some of the posterior cortex intact;3. A complete displacement with various degrees of separation of the fracture fragments.These account for the three Gartland types (GA59, KA01).III. Classification5. To what two major sub-types are supracondylar fractures classified?They are classified into two major subtypes:Extension type - in which the distal fragment is displaced posteriorly and the apex of the fracture site is .Ninety to ninety-five percent of all supracondylar fractures are extension type.The other, less common, type of supracondylar fractures is the Flexion type in which the apex of the fracture site is posterior. These account for anywhere to 1-5 % of all supracondylar fractures (CH01, KA01). 6. How are the extension type supracondylar humeral fractures commonly classified?The classification is based upon the original description reported by Gartland in 1959 (GA59). These types represent no more than the three stages of displacement that are:Type I – no displacement, i.e., none or little displacement, which will result in an acceptable functional and cosmetic outcome.Type II – incomplete displacement in which there is enough intrinsic stability that the fracture can easily be managed by closed reduction and cast applications.Type III – complete or sufficient displacement that the fracture cannot be stabilized by a cast alone but requires some type of surgical stabilization.7. Why all the emphasis on the classification? It dictates the method of treatment as will be seen in the following discussions.IV. Extension Type Supracondylar FracturesTreatment Type I Fractures 8. What are the criteria for Type I Fractures?- It is essentially undisplaced or very minimally displaced- There is significant displacement of the posterior and anterior fat pads. In fact this may be the only sign, as the fracture may not be apparent on routine radiographs.- The determination as to whether there is an acceptable alignment, at least in the saggital plane, is that the anterior humeral line still goes through the ossific nucleus of the capitellum and there is no “crescent sign” or superimposition of the distal end of the capitellum over the olecranon indicating varus alignment.9. Post fracture, if no fracture was seen on the original radiographs how does one confirm that the patient did indeed have an occult Type I supracondylar fracture?There will usually be periosteal new bone formation seen at the edges of the metaphyseal cortices appearing about 2-3 weeks post injury.10. How are Type I Fractures usually treated?The extremity is placed in some type of protective immobilization for three weeks. This can be in the form of a cast or splint at 90 degrees or less. 11. What positions need to be avoided?Two positions need to be avoided, that is hyperpronation and hyperflexion (BA02) by Mapes and Hennrikus (MA98) it was shown that there was a decrease in the blood flow to the distal portion of the forearm when the elbow was hyper flexed and the forearm was placed in full pronation.12. What is the major pitfall of this type?The failure to fully evaluate the fracture and determine that it is truly not significantly displaced.13. What are the two major deformities seen with Type I injuries?1. Medial greenstick collapse. This is due to the relative weakness of the medial column, which allows it to collapse in a varus direction. This can be especially a problem if the patient does not normally have any significant carrying angle. It may require closed reduction and pin fixation (DE95).2. Often the condyles are hyperextended or extended which, clinically, can accentuate the unattractiveness of the varus deformity.14. How can one avoid these complications?By examining the patient (DE95) with a lot of care and coaxing, the elbow can often be brought out into almost full extension. If it is a true Type I lesion, the carrying angle can be evaluated clinically. It is a little bit difficult to determine the clinical alignment in the saggital plane i.e. the ability to flex and extend the elbow or the presence of hyperextension, because of the acute swelling.Type II Fractures15. What are the criteria for Type II Fractures?This is an incomplete fracture in which there is usually some posterior cortical integrity remaining. The integrity must be sufficient to prevent rotation of the distal fragment when the elbow is hyper flexed.16. How are Type II Fractures best treated?They must be reduced and then stabilized. 17. What is the manipulative process?One needs to first correct any coronal malalignment. This is usually done with the forearm pronated.The saggital alignment is then corrected by reestablishing flexion. Hyper flexing the elbow usually does this. In doing so, one usually meets some resistance prior to obtaining full hyperflexion, which is the angle at which the elbow joint reaches its maximum excursion with the distal fragment still in the uncorrected extended position. At this point the elbow is then forced into maximum flexion. This should correct the angular deformity of the distal humerus in the saggital plane.Following correction of the deformity of the saggital plane, the elbow should be brought out into full extension and examined both clinically and radiographically to make sure that the carrying angle has been corrected.18. Post reduction, how is the reduction maintained?The criterion for a Type II fracture is the ability to be stabilized with a long arm cast.Determining the ability to treat these fractures with a cast alone involves testing its’ stability to rotation with the elbow flexed at 120 degrees. The shoulder is fully externally rotated and x-rays are taken to make sure that the reduction has been maintained with the elbow flexed only to 120 degrees. If it stays stable in this position then there is enough internal stability at the fracture site that it can be managed with a cast alone barring severe swelling or vascular compromise. Warning! Flexing to greater than 120 degrees increases the risk of vascular problems. (MI84)19. If the reduction is stable at 120 degrees of flexion how must the cast be applied post reduction?However, stabilization in a cast or splint at 90 degrees is usually not adequate. The elbow must be flexed at least 120 degrees. Allowing the elbow to be flexed to only 90 degrees may result in loss of correction of the shaft-condylar angle. They are best-immobilized post reduction with a Figure-of-8 cast as recommended originally by Rang(RA).It is always important to incorporate the sling into the cast so that the elbow extension can be maintained. Failure to do so will allow the cast to slip into some extension and can result in loss of the reduction.If in Type II Fractures there is any concern with vascular compromise or fracture stability, then it is best to treat this as one would treat a Type III Fracture, that is one in which the fragments are completely displaced. Type III Fractures20. How are extension Type III supracondylar fractures sub classified?They are classified into two major groups: posteromedial and posterolateral. The posterolateral pattern consists of only about 25% of the fractures.21. Does this sub classification make a difference?Yes.22. In what aspects does the sub classification affect the management of Type III supracondylar extension fractures?- It can determine the major nerve or vessel injury.- It can determine the surgical approach if an open reduction is necessary.- It also can determine the risk of later complications (CA95).23. What Type has a greater potential for complications?One must have more respect for the posterolateral fractures because the distal fragment will often be impinging upon the brachial artery and medial nerve (CA95). 24.What is the major concern with the posterolateral fractures?They have a higher risk of:- vascular injuries;- irreducibility.25. What is the major concern with posteromedial fractures?The radial nerve is more vulnerable to injury.26. How are Type III Fractures best treated?Simple. One must first obtain reduction and then maintain the reduction.There is no true emergency to treat these fractures in the middle of the night. Two studies have demonstrated that waiting more than 8 hours to reduce and stabilize these fractures did not increase the incidence of complications or unsatisfactory results (LE02A,ME01). 27. What does the manipulative process entail?It consists of three steps:1. The alignment needs to be corrected. With the elbow in extension, you align the distal fragment to the proximal fragment.2. Re-establish length. This often requires someone to apply counter traction as the surgeon applies traction to re-establish length.2. The angulation and posterior displacement of the distal fragment needs to be corrected.Sometimes the distal fragment needs to be a little bit hyperextended. Care must be taken to avoid injury to the neurovascular structures when this occurs. Traction is applied to the forearm with the elbow in semi-flexion and at the same time pressure is applied to the anterior portion of the distal fragment to push it posteriorly. This facilitates the reduction of the distal fragment to the proximal fragment. Sometimes the distal portion of the proximal fragment is impaled through the biceps and the brachialis may need to be milked off the fragment (AR97).Once the fragments are reduced, the elbow is then hyperflexed and hyperpronated. 137160030480If one is unable to get the elbow into hyperflexion the process needs to be stopped because there may be interposed tissue between the fragments.00If one is unable to get the elbow into hyperflexion the process needs to be stopped because there may be interposed tissue between the fragments.Then, with the elbow fully flexed the reduction is checked with the shoulder fully, externally rotated.28. How does one maintain the reduction once obtained?The use of a Figure-of-Eight cast is no longer acceptable in maintaining the reduction of Type III fractures. To hold the distal fragment stable so that it does not displace with rotation requires full flexion of the elbow. This carries a significant risk for vascular compromise.29. Since a cast is inadequate for maintaining the reduction of type III fractures, what is the best way to maintain the reduction?The standard now for maintaining the reduction is percutaneous pin fixation(BO92).30. In what manner may the pins be used?Medial lateral pins.31. What are the advantages of the medial-lateral pin construct?-It is the most stable construct of all the pin placement patterns for rotational stability. (LE02,ZI94)-It allows the angle to be extended once the pins are inserted so that the maintenance of the carrying angle can be assessed.32.What are the disadvantages of the medial-lateral construct?The primary disadvantage is the possibility of ulnar nerve injury.33.How can the danger of ulnar nerve injury be minimized?The ulnar nerve can be protected by making an incision directly over the medial epicondyle and visualizing the ulnar nerve or epicondyle directly so that the location of the pin is exactly in the center of the epicondyle.Another technique is to localize the position of the ulnar nerve with a nerve stimulator(WI02).34. What are the principles of lateral pin fixation?This usually involves two lateral pins which are placed parallel or divergent.The advantages being that that are easy to apply and there is almost no risk of nerve injury.The disadvantage is that there is poor rotational stability. Again, the pins must be parallel or divergent. Pins crossing at the fracture site are an unstable construct and may not hold the reduction.However, loss of rotation of the distal fragment, if the coronal alignment is maintained is usually of little or no clinical significance. The elbow function and clinical appearance is the same as those who have not developed a rotation (GR01,LE02,SK01).35. How can the rotational stability with two lateral pins be enhanced?Adding a third lateral pin. This third lateral pin usually goes very obliquely up to the diaphysis and may even almost be intramedullary. It seems to enhance rotational stability almost equal to that of medial-lateral pins (ZI94).36. What are the advantages and disadvantages of the three-lateral pin construct?Advantages – In studies by Zionts (ZI94) and associates, this construct is almost as strong as medial-lateral pins Disadvantages – In larger patients there may still be some rotational instability. Even with three lateral pins, there may be a need to supplement with a medial pin.37. Following pin fixation how are these Type III Fractures managed?Usually all that is necessary is immobilization in cast or splint at 90 degrees or less for about three weeks.38. What does the pucker sign indicate?It indicates that the distal spike of the proximal fragment is impaled in the subcutaneous tissues and possibly button-holed through the brachialis muscle which may make the fracture irreducible. This impaled muscle may be released by the “milking maneuver” in which the brachialis muscle is milked distallyoff the spike of the proximal fragment(AR97).39. In those irreducible fractures, what are the preferred surgical approaches?Posterior lateral fractures: The appropriate approach to a posterior lateral fracture is an anterior medial approach which allows visualization of the median nerve and brachial artery both which are usually tented across the distal spike of the proximal fragment. This allows direct visualization of these anterior interposed neurovascular tissues. This is usually done through an anteromedial incision.Posterior medial fractures can be approached through an anterolateral incision to allow direct visualization of the radial nerve as it is usually tented over the distal fragment.40. What about the posterior approach?Overall, this is probably the most widely used surgical approach. It usually involves a posterior triceps splitting approach(SC02,SR00).The advantages are: it is an easier approach and it allows direct visualization of the fracture site.The disadvantages are: it injures virgin tissue and one is unable to visualize the anterior nerves and arteries that are usually interposed in irreducible fractures.41. What is the primary purpose of an open reduction?The philosophy is to:-remove the interposed structures;-then facilitate a closed reduction; and-perform a percutaneous pin fixation.The main interposed structure is a flap of periosteum that tears proximally but remains attached to the distal fragment. This flap of periosteum serves as a guide to bringing the distal fragment forward to reduce it(AB82).Other interposed structures include brachialis muscle and on occasion the neurovascular structures.There does not appear to be any risks regarding the final outcome or rate of complications in performing an open reduction on irreducible Type III fractures. It is now a widely accepted procedure(CR92,FL98,KE01,RE01). 42.What about late appearing fractures?If the fragments are in apposition to each other and there is already periosteal new bone formation, it is often best to wait as the remodeling process may provide surprising results. 43.What about those late appearing fractures that do not fully remodel? Again, once periosteal bone formation has begun it may be best to wait and see how much remodeling occurs and, if need be, a corrective osteotomy be done when the patient has regained full motion and muscle strength.44.What are the risks of doing a late open reduction?Myositis ossificans. Thus when faced with a late appearing fracture one is faced with the dilemma of doing a delayed open reduction and risking myositis ossificans which can produce significant loss of motion (LA91). Or, wait and do a corrective osteotomy when the patient has regained recovered full motion.45.In addition to evaluating the neurovascular status, what else needs to be done in assessing Type III supracondylar fractures?Always check for ipsilateral fractures.46.Ipsilateral fractures, how do they need to be stabilized?Both the supracondylar and radius and ulna fractures need to be stabilized with pins(RO01,SI02).In those with ipsilateral distal radial fractures, usually the supracondylar fracture needs to be reduced and stabilized with percutaneous pins first.In those with ipsilateral shaft fractures one has to first establish intramedullary pin fixation so that this can be used to effect a reduction of the supracondylar fracture which also needs to be stabilized with percutaneous pins.47. How do flexion-type supracondylar fractures present?In the same manner as extension-type fractures:Type I – undisplaced, no reduction needed;Type II - enough intrinsic stability to be treated with a cast alone; andType III – no intrinsic stability, needs surgical stabilization.48. What are the criteria of acceptability for a Type I flexion injury?There is no good data. Probably there would be no more than 20 degrees loss of the shaft condylar angle. If it is not aggressively corrected the patient may lose elbow extension.49. What is involved in the management of Type II flexion injuries?Again, the process should be closed reduction and stabilization with a long-arm extension cast(WI91).50.What are some of the clues to the occult Type III flexion supracondylar fractures?The distal fragment is not extended, also is not flexed and is sometimes rotated with the medial segment of the distal fragment rotated anteriorly. This then puts the medial spike of the proximal fragment posteriorly to press against the ulnar nerve and may actually become posterior to the intramuscular septum. This often is the cause of the irreducibility of these fractures by closed methods.51.What is the operative approach for these Type III flexion supracondylar fractures?It is usually an anterior medial approach in which the longitudinal aspect of the hockey-stick incision is a little bit more posterior to allow visualization of the ulnar nerve, the medial spike, and the anterior nerve vascular bundle along with the interposed tissue. 52. So what’s the message with Type III flexion supracondylar fracture injuries?There is often a very high incidence of irreducibility requiring an open reduction.If critically evaluated and these occult criteria are utilized, the incidence of flexion supracondylar fractures may be more common than originally suspected. ReferencesAB82. Abraham E, Powers T, Witt P, Ray RD. Experimental hyperextension supracondylar fractures in monkeys. Clin Orthop 171:309, 1982Discarded monkey autopsy specimens were used to investigate the mechanism of supracondylar hyperextension fracture. As the fracture progressed from mild angulation to complete lateral or medial displacement, the anterior periosteum first was detached from the bone and then stripped distally before tearing over the edge of the proximal fragment. Stability or reduction by acute elbow flexion and forearm pronation, owing to compressive forces, was transmitted through the elbow joint on the medial side of the fracture, and stability was not significantly influenced by a bridging periosteal hinge or forearm musculature. Forearm supination and elbow flexion of less than 90 degrees resulted in less stability. The influence of acute elbow flexion and forearm pronation was diminished when the fracture was distracted by traction. Interposition of the anterior periosteum in displacement fractures prevented anatomic reduction.AR97. Archibeck MJ, Scott SM, Peters CL. Brachialis muscle entrapment in displaced supracondylar humerus fractures: a technique of closed reduction and report of initial results. J Pediatr Orthop 17:298,1997. A retrospective review was conducted of 152 extension-type supracondylar humerus fractures in 151 children. Ninety-two (61%) of 152 of these fractures were displaced (Gartland type III). Initial irreducibility was present in 20 of the 92 displaced fractures. Brachialis muscle interposition was diagnosed by physical examination or intraoperative findings in 18 (90%) of the 20 initially irreducible fractures. Sixteen of the fractures with brachialis muscle interposition underwent an attempt at freeing the impaled proximal fragment by the described "milking maneuver." The maneuver was successful in 15 of the 16 patients and was followed by closed reduction and percutaneous pinning. Three of the remaining four cases required open reduction and pinning. We identify the incidence of initial irreducibility in displaced supracondylar humerus fractures, describe clinical findings suggestive of brachialis entrapment, and demonstrate the milking maneuver to be a valuable technique in the treatment of displaced supracondylar fractures with brachialis interposition.BA02. Battaglia TC, Armstrong DG, Schwend RM. Factors affecting forearm compartment pressures in children with supracondylar fractures of the humerus. Journal of Pediatric Orthopedics.;22:431,2002. This study evaluated forearm compartment pressures in 29 children with supracondylar humerus fractures. Pressures were measured before and after reduction in the dorsal, superficial volar, and deep volar compartments at the proximal 1/6th and proximal 1/3rd forearm. Pressures in the deep volar compartment were significantly elevated compared with pressures in other compartments. There were also significantly higher pressures closer to the elbow within each compartment. Fracture reduction did not have a consistent immediate effect on pressures. The effect of elbow flexion on post-reduction pressures was also evaluated; flexion beyond 90 degrees produced significant pressure elevation. We conclude that forearm pressures after supracondylar fracture are greatest in the deep volar compartment and closer to the fracture site. Pressures greater than 30 mm Hg may exist without clinical evidence of compartment syndrome. To avoid unnecessary elevation of pressures, elbows should not be immobilized in >90 degrees of flexion after these injuries.BO92. Boyd DW, Aronson DD Supracondylar fractures of the humerus: a prospective study of percutaneous pinning. J Pediatr Orthop 12:789,1992.In 1981, we designed a protocol to treat displaced supracondylar fractures using a modified technique of closed reduction and percutaneous pinning. After the fracture was internally fixed, intraoperative anteroposterior (AP) radiographs of each distal humerus were compared. The reduction and pinning was accepted only if the radiographs demonstrated that Baumann's angle was < or = 4 degrees of that on the normal side. Seventy-one patients had clinical and radiographic evaluations at an average of 2 years 6 months after the operation. According to Flynn's criteria, the results were satisfactory in 70 patients and unsatisfactory in one. No patient had a cubitus varus deformity at follow-up evaluation.CA95. Campbell CC, Waters PM, Emans JB, Kasser JR, Millis MB.Neurovascular injury and displacement in type III supracondylar humerus fractures. J Pediatr Orthop 15:47,1995.From July 1987 to January 1991, 59 consecutive type III supracondylar humerus fractures in children were identified at Children's Hospital, Boston. Twenty-nine patients (49%) had evidence of neurovascular compromise. The median nerve was involved in 15 (52%) of these patients and was associated with posterolateral displacement in 87% of cases. The radial nerve was involved in eight (28%) of these patients and was associated with posteromedial displacement in every case. Injuries to the brachial artery occurred in 11 (38%) of these patients and was associated with posterolateral displacement in 64% and posteromedial displacement in 36% of cases. We conclude that posterolateral displacement in type III supracondylar humerus fractures is strongly associated with median nerve injuries. Posteromedial displacement is responsible for injuries. Posteromedial displacement is responsible for injuries to the radial nerve in virtually every instance. Brachial artery injuries may occur with either type of displacement. Neurovascular injury is higher than previously reported in these fractures.CH95. Cheng J, Lam T, Shen W. Closed reduction and percutaneous pinning for type III displaced supracondylar fractures of the humerus in children. J Orthop Trauma:9:511,1995. From 1985 to 1991, 623 cases of supracondylar fracture of the humerus in children were admitted to one center, of which 403 were analyzed in detail. Of these, 180 cases were classified as Gartland type III extension fractures, and 111 were treated via primary closed reduction and percutaneous smooth Kirschner wire pinning, of which 82 were followed up for an average of 3.5 years and were studied in detail clinically and radiologically. There were two cases of superficial pin tract infection and one of ulnar nerve palsy associated with the pinning. Nineteen fractures (10.5%) had an initial nerve palsy related to the injury. All recovered completely from 4 weeks to 40 weeks postinjury. Only one of nine cases (5%) with absent radial pulse required exploration. Eighty percent of all cases had excellent or good function according to the Flynn criteria of elbow assessment. The most important factor correlating with the final varus deformity was found to be the difference in Baumann's angle between the injured and the normal side after closed reduction and pin fixation. The results of cross pinning in eight cases were not found to be different from those of the lateral pinning group (74 cases). Ipsilateral fracture of the same limb occurred in 4.4% of the cases, the majority being a fracture of the distal radius. The average anesthetic time for the procedure was 54 min, and the average hospital stay was 2.9 days. Our study shows that cross or lateral percutaneous pinning was found to be effective in the treatment of Gartland type III extension fractures with a high success rate and minimal complications.CH01. Cheng JC, Lam TP, Maffulli N. Epidemiological features of supracondylar fractures of the humerus in Chinese children. Journal of Pediatric Orthopaedics, Part B.10:63,2001.We studied 450 children with a supracondylar fracture of the humerus in the period 1991 to 1995, and were able to collect full management details in 403 of them (253 boys and 150 girls). The median age at presentation was 6 years (6.6 years in boys, and 5 years in girls), with the nondominant humerus 1.5 times more commonly injured. Fifteen percent of children presented more than 1 day after the injury. Garland type III fractures constituted 45% of cases, type I 30%, and type II 24%, with flexion type fractures present only in 1% of the children. A nerve injury was associated with the fracture in 19 cases. Although the radial pulse was not palpable at presentation in nine patients, only one child had diminished distal circulation requiring exploration. Concomitant fractures were present in 14 patients. Elbow hyperextension was greater than in a comparable group of noninjured children. Open reduction was necessary in 20% of these children, most being managed by manipulation under anaesthesia, at times associated with percutaneous Kirschner wiring. The hospital stay was 2 days or less in two-thirds of the patients, with more than 90% discharged home within 1 week of admission. In conclusion, many Chinese patients attend hospital later than their Western counterparts, and the rate of flexion-type injuries is low.CR92. Cramer KE, Devito DP, Green NE. Comparison of closed reduction and percutaneous pinning versus open reduction and percutaneous pinning in displaced supracondylar fractures of the humerus in children. J Orthop Trauma 6:407,1992A retrospective review of 29 children with displaced supracondylar humerus fractures was performed. Fifteen patients treated with closed reduction and percutaneous pinning and 14 patients treated with open reduction and percutaneous pinning were evaluated at a minimum of 18 months (range 18-80 months). Results were graded according to the criteria of Flynn et al. (Flynn JC, Matthews JG, Benoit RL: Blind pinning of displaced supracondylar fractures of the humerus in children. J Bone Joint Surg [Am] 56:263-272, 1974) using both cosmetic and functional evaluations. Excellent or good results were obtained in 14 of the 15 fractures treated with closed reduction and percutaneous pinning and in 12 of the 14 fractures treated with open reduction and percutaneous pinning. The three fair cosmetic results were associated with inadequate reduction and residual medial angulation. Ten to 15 degrees of motion loss occurred in three older patients. One patient in each group had a minor pintract infection. There were no cases of iatrogenic nerve injury or myositis ossificans. The treatment goal in displaced supracondylar humerus fractures in children is anatomic reduction. If an anatomic reduction cannot be achieved with closed reduction, open reduction is indicated. This can be done without an increased risk of complications.DE95. De Boeck H, De Smet P, Penders W, De Rydt D. Supracondylar elbow fractures with impaction of the medial condyle in children. Journal of Pediatric Orthopedics. 15:444,1995We reviewed the cases of 13 children with supracondylar elbow fractures with impaction of the medial wall. The displacement was underestimated in two patients and treated as a minimally displaced fracture by simple immobilization without reduction, resulting in a cubitus varus deformity. In one patient, the correct diagnosis was made, but treatment by reduction was refused by the parents. A loss of carrying angle of 10 degrees resulted from this. Two patients referred for treatment of cubitus varus were treated elsewhere for the initial injury: one by reduction and plaster cast immobilization and the other by simple immobilization without reduction. Two children with a supracondylar fracture with buckling of the medial condyle without prominent deformity were not reduced and showed no deformity at follow-up. Six children with collapse of the medial condyle, treated by closed reduction and percutaneous pinning, all had a normal carrying angle at follow-up. We believe that this method is safe to prevent varus angulation.FL98. Fleuriau-Chateau P, McIntyre W, Letts M. An analysis of open reduction of irreducible supracondylar fractures of the humerus in children. Can J Surg 41:112,1998.OBJECTIVES: To review experience with irreducible supracondylar fractures requiring open reduction in children, and to propose guidelines for an open approach to supracondylar fractures. DESIGN: A chart review. SETTING: The Children's Hospital of Eastern Ontario (CHEO), a pediatric centre with a large referral base. PATIENTS: Forty-one children (18 boys 23 girls, average age 7 years), who had open reduction of irreducible supracondylar fractures at the CHEO over a 10-year period (1985 to 1995). Of these 41 children, 7 were lost to direct follow-up. INTERVENTIONS: After closed reduction of displaced supracondylar fractures of the humerus failed, all patients underwent open reduction and percutaneous fixation in the operating room. Before operation, 6 had no radial pulse, 5 lost their pulse with flexion after reduction and 4 had unstable fracture patterns. MAIN OUTCOME MEASURES: Assessment of elbow range of motion and carrying angle, distal neurovascular status and radiographic measurement of the Baumann angle and the humerocapitellar angle. RESULTS: In 25 children, the humerus was found to have "buttonholed" through the brachialis muscle; 1 had entrapment of the common flexor muscle at its origin and 1 had entrapment of the triceps. In 15 children there was entrapment or tethering of the median nerve and radial nerve or brachial artery, or both, but this was not predictive of preoperative neurovascular deficit, which was recorded in 21 patients (fully recovered). At follow-up, the Baumann angle and the humerocapitellar angle differed by an average of 2 degrees and 5.3 degrees respectively compared with the unaffected arm. Range of motion was satisfactory in 94% of patients, and there was no significant cubitus varus. CONCLUSION: Open reduction of supracondylar fractures is a safe and effective procedure, for which orthopedists should should lower their threshold, given certain appropriate indicators.GA59. Gartland JJ. Management of supracondylar fractures of the humerus in children. Surg Gynecol Obstet 1959;109:145–154.The classic article in which Type III extension fractures are divided into threeTypes based upon the degree of displacement of the distal fragment.GR01. Gordon JE, Patton CM, Luhmann SJ, Bassett GS, Schoenecker PL. Fracture stability after pinning of displaced supracondylar distal humerus fractures in children. Journal of Pediatric Orthopedics.21:313, 2001.Between January 1, 1994 and December 31, 1997, we evaluated 138 children with displaced supracondylar distal humerus fractures treated by closed reduction and percutaneous pinning. There were 49 type II fractures and 89 type III fractures. Three principal pin configurations were used at the surgeon's discretion: 2 lateral pins (42 fractures), 1 medial and 1 lateral pin (37 fractures), and 1 medial and 2 lateral pins (57 fractures). There was no statistically significant difference in clinical stability between these groups. One type III fracture pinned using two lateral pins showed marked rotational instability. We recommend using two lateral pins when treating type II fractures. Type III fractures should be treated using two lateral pins initially and, if the elbow demonstrates significant intraoperative rotational instability, a medial pin should be added. If a medial pin is necessary, and the ulnar nerve cannot be identified by palpation, a small incision should be made and the pin placed under direct vision.KE01. Kaewpornsawan K. Comparison between closed reduction with percutaneous pinning and open reduction with pinning in children with closed totally displaced supracondylar humeral fractures: a randomized controlled trial. Journal of Pediatric Orthopaedics, Part B. 2001;10-2:131-7.This was a randomized controlled trial of 28 children 1 year to 12 years of age with closed totally displaced supracondylar humeral fracture. The purpose of the study was to compare closed reduction and pinning (group A) and open reduction and pinning (group B). Each group consisted of 14 children. The general characteristics of both groups (age, sex side, displacement, nerve injury preoperatively) were statistically the same (P > 0.05). All cases healed with good alignment without cubitus varus, without infection and with a good range of motion except for one. The mean +/- standard deviation of the Baumann's angle difference between the injured and uninjured side were 2.32 +/- 1.6 degrees in group A (range, 0-6.5 degrees) and 2.45 +/- 1.8 degrees in group B (range, 0-6.5 degrees). This difference was statistically not significant (P = 0.8). By Flynn criteria, group A had good to excellent results in 100%, and group B had good to excellent results in 93% and fair in 7%. This difference was not statistically significant (P = 1). The satisfaction score (0-10) was significantly higher in group A for both parents' and evaluator's (blinded to treatment) perspective (P = 0.017 and 0.019, respectively). The author concludes that both treatments gave good results. Closed reduction should be performed first and, if it fails, then open reduction can be performed. This will produce good results in the hands of an experienced surgeon.KA01. KasserJR, BeatyJH. Supracondylar Fractures of the Humerus. Chapt.14 in Rockwood and Wilkins’ Fractures in Children, Vol.III. 5th. Ed. Lippincott Williams and Wilkins. Phila.Pa. 2001A textbook chapter that describes in detail almost all of the basic concepts regarding the management of supracondylar fractures in children. LA91. Lal GM, Bhan S. Delayed open reduction for supracondylar fractures of the humerus. Int Orthop 15:189,1991. Twenty children with grade IV supracondylar fractures of the humerus had an open reduction 11 to 17 days after injury. The delay was due to swelling and blisters. Almost all the patients developed myosotis ossificans to some degree with loss of elbow flexion and extension. Most patients recovered a useful range of movement and there were no complications. A posterior approach with V-Y plasty of the triceps makes it easy to align the fragments and reduces the incidence of cubitus varus. Apprehension about the risk of increasing the extent of myositis ossificans is unfounded.LE02. Lee SS, Mahar AT, Miesen D, Newton PO. Displaced pediatric supracondylar humerus fractures: biomechanical analysis of percutaneous pinning techniques. Journal of Pediatric Orthopedic;22:440, 2002.Supracondylar humerus fractures are a common childhood occurrence. Displaced fractures are typically treated with closed reduction and percutaneous pinning. Controversy continues over the appropriateness of various pinning techniques. The most common include crossed or lateral pins. A biomechanical comparison of crossed pins, "parallel" lateral pins, and "divergent" lateral pins was performed using a pediatric synthetic bone model. Mechanical testing of each pin configuration was performed in extension, varus, valgus, internal rotation, and external rotation. The divergent configuration provided statistically greater stability than parallel pins under varus and valgus loading. Divergent pins had similar stability compared with crossed pins in extension, varus, and valgus testing. In axial rotation testing, crossed pins were more stable. If the surgeon feels confident in the ability of lateral pins to provide satisfactory fracture stability, divergent lateral pins provide greater stability than parallel lateral pins while avoiding ulnar nerve injury (associated with crossed pins).LE02. Leet AI, Frisancho J, Ebramzadeh E. Delayed treatment of type 3 supracondylar humerus fractures in children. Journal of Pediatric Orthopedics. 22:203,2002.A retrospective review of 158 type 3 supracondylar humerus fractures was undertaken to determine whether any correlation exists between an increased time from injury to surgery and four unfavorable results: a longer operative time, an increase in hospital stay, an increase in the need to open the fracture, or an increase in unsatisfactory outcomes. The average age of the patients was 5.0 years. Five children had nerve injury on initial examination, and no arm was poorly perfused. The average time from injury to evaluation in the emergency department was 9.8 hours and the average time from the emergency department to surgery was 11.5 hours. The average total time from injury to surgical treatment was 21.3 hours. The patients were in the hospital between 1 to 6 days. The average operative time was 53 minutes. Thirty patients had unsatisfactory results, defined as a pin infection, more than 15 degrees loss of motion in any plane, loss of normal carrying angle, neuropraxia, or retained hardware. There was no correlation between an increase in time to surgical intervention and longer operative time or need to open the fracture site, nor was there an indication that the delay to surgical treatment resulted in a longer hospital stay or an increase in unsatisfactory results.MA98. Mapes R, Hennrikus W. The effect of elbow position on the radial pulse measured by Doppler ultrasonography after surgical treatment of supracondylar elbow fractures in children. J Pediatr Orthop 18:441,1998. We performed a prospective study of 20 patients with displaced extension supracondylar humerus fractures and evaluated the effect of elbow flexion, forearm supination, and forearm pronation on blood flow to the injured arm after closed reduction and Kirschner wire fixation. Ten patients had a Gartland type II fracture and 10 patients had a Gartland type III fracture. After closed reduction and percutaneous pinning, the radial pulse was examined with Doppler ultrasonography starting with the elbow in extension. The elbow was slowly flexed, and the angle of elbow flexion at which the radial pulse disappeared was determined. This angle of elbow flexion was measured with the forearm in both supination and pronation. Gartland type III fractures demonstrated less elbow flexion prior to radial pulse ablation compared to Gartland type II fractures when the forearm was placed in supination (p = 0.001) and in pronation (p = 0.005). Supination allowed > or = 5 degrees of elbow flexion prior to radial pulse ablation in six Gartland type II and four Gartland type III fractures. We concluded that after closed reduction and percutaneous Kirschner wire fixation of displaced extension supracondylar fractures, vascular safety is enhanced by extending the elbow and supinating the forearm. The ideal position of elbow immobilization depends on the amount of swelling and the presence of a radial pulse.ME01. Mehlman CT, Strub WM, Roy DR, Wall EJ, Crawford AH. The effect of surgical timing on the perioperative complications of treatment of supracondylar humeral fractures in children. Journal of Bone & Joint Surgery.83A:323,2001.BACKGROUND: The purpose of this study was to evaluate the perioperative complication rates associated with early surgical treatment (eight hours or less following injury) and delayed surgical treatment (more than eight hours following injury) of displaced supracondylar humeral fractures in children. METHODS: Fifty-two patients had early surgical treatment and 146 patients had delayed surgical treatment of a displaced supracondylar humeral fracture. The perioperative complication rates of the two groups were compared with the use of bivariate and multivariate statistical methods. RESULTS: There was no significant difference between the two groups with respect to the need for conversion to formal open reduction and internal fixation (p = 0.56), pin-track infection (p = 0.12), or iatrogenic nerve injury (p = 0.72). No compartment syndromes occurred in either group. Power analysis revealed that our study had an 86% power to detect a 20% difference between the two groups if one existed. CONCLUSIONS: We were unable to identify any significant difference, with regard to perioperative complication rates, between early and delayed treatment of displaced supracondylar humeral fractures. Within the parameters outlined in our study, we think that the timing of surgical intervention can be either early or delayed as deemed appropriate by the surgeon.MI84. Millis MB, Singer IJ, Hall JE. Supracondylar fracture of the humerus in children: further experience with a study in orthopaedic decision making. Clin Orthop 188:90,1984.In a study of the results of each therapeutic act in the treatment program of displaced supracondylar fractures of the humerus, 108 consecutive children were analyzed. An initial attempt at closed reduction was noted in 101 cases, with the attempt successful in 61. Of these elbows, 19 were flexed at least 120 degrees following reduction, with all 19 maintaining reduction. Twenty-two of the remaining reduced fractures were splinted in less than 120 degrees of flexion; 19 lost reduction. Traction alone, via olecranon pin or skin, was unsuccessful in achieving reduction and unreliable in maintaining reduction once achieved. Crossed Kirschner wires, placed percutaneously or under direct visualization, were uniformly successful in maintaining reduction. From these data an algorithm has been constructed to facilitate objective decision-making in the treatment of this challenging fracture.NO99. Nork SE, Hennrikus WL, Loncarich DP, Gillingham BL, Lapinsky AS. Relationship between ligamentous laxity and the site of upper extremity fractures in children: extension supracondylar fracture versus distal forearm fracture. Journal of Pediatric Orthopaedics, Part B. 8:90 1999.Eighty children who had fallen on an outstretched hand and sustained either a displaced supracondylar fracture (group 1) or a displaced distal forearm fracture (group 2) were prospectively studied. Ligamentous laxity in these 80 patients was determined by four methods: (a) contralateral elbow hyperextension, (b) knee hyperextension, (c) the ability to touch the thumb to the ipsilateral forearm, and (d) the ability to extend the thumb past the ulnar border of the clenched fist. Elbow hyperextension averaged 10.5 degrees in group 1 and 4.4 degrees in group 2 (P < 0.0001). Knee hyperextension averaged 7.2 degrees in group 1 and 2.4 degrees in group 2 (P < 0.001). Twenty-one of 38 patients in group 1 (55%) compared with 8 of 42 patients in group 2 (19%) could touch the thumb to the ipsilateral forearm (P < 0.001). Twenty-seven of 38 patients in group 1 (71%) compared with 5 of 42 patients in group 2 (12%) could extend the thumb past the ulnar border of the clenched fist (P < 0.001). The authors conclude that a child who demonstrates ligamentous laxity is more likely to sustain an extension supracondylar humerus fracture than a distal forearm fracture when he or she falls on the outstretched hand to break the force of the fall.RA73. Rang,M Personal communication 1973.RE01. Reitman RD, Waters P, Millis M. Open reduction and internal fixation for supracondylar humerus fractures in children. Journal of Pediatric Orthopedics.21:157, 2001Eight hundred sixty-two supracondylar humerus fractures were treated between January 1984 and July 1997. Sixty-five (8%) patients were managed with open reduction and internal fixation with pins. The remaining 797 patients (92%) were managed with either casting, closed reduction with or without percutaneous pinning, or traction. Of the 65 patients managed with open reduction, 46 (71%) of these fractures were irreducible, 16 (24%) had associated vascular compromise, eight (12%) were open, and one was associated with a postreduction nerve palsy and nonanatomic reduction. According to the criteria of Flynn et al. 18 (55%) elbows were rated excellent, eight (24%) were rated good, three (9%) were rated fair, and four (12%) were rated poor after an average of 5.8 months postinjury. This study indicates that highly satisfactory results can be obtained in severely displaced fractures managed with open reduction in these situations.RO01. Roposch A, Reis M, Molina M, Davids J, Stanley E, Wilkins K, Chambers HG. Supracondylar fractures of the humerus associated with ipsilateral forearm fractures in children: a report of forty-seven cases. Journal of Pediatric Orthopedics.21:307,. 2001.Supracondylar fractures of the humerus associated with ipsilateral forearm fractures are uncommon and treatment recommendations are controversial. The purpose of this study was to determine whether pin fixation of both fracture components, humerus and forearm, would improve the outcome. In a two-center trial, 884 children sustaining supracondylar fractures of the humerus were retrospectively reviewed, and 47 (5.3%) showed associated ipsilateral forearm fractures. Of those, 29 underwent Kirschner-wire fixation of the forearm fracture, and 18 of the forearm fractures were treated with casting alone. Three of the 18 forearm fractures with casting alone reangulated. There were no reangulations in the patients who had pin fixation of their fractures. There were no complications due to pin fixation in the humerus or the forearm. In unstable supracondylar humerus and forearm fractures, stabilization with pin fixation to prevent reangulation should be considered.SC02. Scola E, Jezussek D, Kerling HP, Yedibela S. [Dislocated supracondylar humerus fracture in the child. Surgical technique and outcome with dorsal approach]. Unfallchirurg. 105:95,2002.Anatomical reduction and stabilization of displaced supracondylar humeral fractures in children is necessary to obtain good results. For most cases percutaneous crossed pinning is recommended. Sometimes open reduction is necessary but even in these cases neurological complications and varus deformities have been reported. So the technique of open pinning was modified. From 1995 to 1998 22 children were treated by a dorsolateral approach. The fracture was stabilized by crossed pinning: The proximal K-wire is drilled 10 degrees ascending to the dorsal humerus through the medial pillar into the ventral part of the medial epicondyle, after shortening it is not bent. The distal K-wire stabilizes the lateral pillar, after shortening its end is bent down. Immobilization for 3-4 weeks, mobilization is done by the patient. The implants are removed 2 weeks later. The follow up in 21 out of 22 patients (8-57 months, mean 35 months) according to Flynn's criteria showed 16 excellent, 4 good and 1 fair result. The fair result was due to valgus deformity. One patient has been reoperated due to displacement of K-wire. Neither iatrogenic nerve lesions nor varus deformities nor infections did occur. The dorsolateral approach combined with the above mentioned technique of pinning shows excellent and good results..SI02. Siemers F, Obertacke U, Fernandez ED, Olivier LC, Neudeck F. [Combination of ipsilateral supracondylar humeral- and forearm fractures in children]. Zentralblatt fur Chirurgie. 127:212,2002.In an 11-year period, from 01. 08. 1987 to 31. 08. 1998, a total of 72 children (mean age 7.6 years, range 2-12 years) with dislocated supracondylar humeral fractures were treated surgically in the Department for Traumatology, University Hospital, Essen. The combination of supracondylar humeral fracture and ipsilateral forearm fracture occurred in 8 children (11.1 %). 4 revealed a complete forearm fracture in the distal third, 4 children a fracture of the distal physis (Salter-Harris type II). The supracondylar humeral fractures were reduced openly via a single lateral approach and stabilized by crossed K-wire fixation. The distal forearm fractures were treated by closed reduction and percutaneous pinning. Fractures of the distal physis were treated by closed reduction and application of an above elbow cast. Excellent results were achieved in all children with ipsilateral supracondylar and forearm fractures.SK01. Skaggs DL, Hale JM, Bassett J, Kaminsky C, Kay RM, Tolo VT. Operative treatment of supracondylar fractures of the humerus in children. The consequences of pin placement. Journal of Bone & Joint Surgery.;83A:735,2001.BACKGROUND: The commonly accepted treatment of displaced supracondylar fractures of the humerus in children is fracture reduction and percutaneous pin fixation; however, there is controversy about the optimal placement of the pins. A crossed-pin configuration is believed to be mechanically more stable than lateral pins alone; however, the ulnar nerve can be injured with the use of a medial pin. It has not been proved that the added stability of a medial pin is clinically necessary since, in young children, pin fixation is always augmented with immobilization in a splint or cast. METHODS: We retrospectively reviewed the results of reduction and Kirschner wire fixation of 345 extension-type supracondylar fractures in children. Maintenance of fracture reduction and evidence of ulnar nerve injury were evaluated in relation to pin configuration and fracture pattern. Of 141 children who had a Gartland type-2 fracture (a partially intact posterior cortex), seventy-four were treated with lateral pins only and sixty-seven were treated with crossed pins. Of 204 children who had a Gartland type-3 (unstable) fracture, fifty-one were treated with lateral pins only and 153 were treated with crossed pins. RESULTS: There was no difference with regard to maintenance of fracture reduction, as seen on anteroposterior and lateral radiographs, between the crossed pins and the lateral pins. The configuration of the pins did not affect the maintenance of reduction of either the Gartland type-2 fractures or the Gartland type-3 fractures. Ulnar nerve injury was not seen in the 125 patients in whom only lateral pins were used. The use of a medial pin was associated with ulnar nerve injury in 4% (six) of 149 patients in whom the pin was applied without hyperflexion of the elbow and in 15% (eleven) of seventy-one in whom the medial pin was applied with the elbow hyperflexed. Two years after the pinning, one of the seventeen children with ulnar nerve injury had persistent motor weakness and a sensory deficit. CONCLUSIONS: Fixation with only lateral pins is safe and effective for both Gartland type-2 and Gartland type-3 (unstable) supracondylar fractures of the humerus in children. The use of only lateral pins prevents iatrogenic injury to the ulnar nerve. On the basis of our findings, we do not recommend the routine use of crossed pins in the treatment of supracondylar fractures of the humerus in children. If a medial pin is used, the elbow should not be hyperflexed during its insertion. SA97. Sabharwal S,Tredwell S, Beauchamp R, et al. Management of pulseless pin hand in pediatric supracondylar fractures of humerus. J PediatrOrthop 17:303,1999. Thirteen (3.2%) of 410 patients seen in British Columbia's Children's Hospital in Vancouver from January 1984 to September 1992 with supracondylar fractures did so with an absence of a radial pulse in an otherwise well perfused hand. A combination of segmental pressure monitoring, color-flow duplex scanning, and magnetic resonance angiography (MRA) appears to be a valid, noninvasive, and safe technique in evaluating patency of the brachial artery and collateral circulation across the elbow. Based on this study, early revascularization of a pulseless otherwise well-perfused hand in children with type 3 supracondylar fractures, although technically feasible and safe, has a high rate of asymptomatic reocclusion and residual stenoses of the brachial artery. Therefore a period of close observation with frequent neurovascular checks should be completed before more invasive correction of this problem is contemplated.SR00. Srivastava S. The results of open reduction and pin fixation in displaced supracondylar fractures of the humerus in children. Medical Journal of Malaysia.;55-Suppl C:44,2000.The treatment of displaced supracondylar fracture humerus (Gartland Type III) in children continues to be a challenging problem. We did a retrospective study of such fractures treated in Hospital Muar, over a 2 years period (from January 1998 to December 1999). A total of 42 cases with displaced supracondylar fractures, treated with open reduction and internal fixation were studied. All cases were operated using a posterior triceps splitting approach and crossed kirschner wires were used to stabilize the fracture site. An excellent outcome was seen in 34 patients (81%) and a good outcome in 7 patients (17%). The incidence of complications such as pin tract infection (14%), nerve injury (2%) was very low. None of the patients had vascular complications or myositis ossificans.WI91. Williamson DM, Cole WG. Flexion supracondylar fractures of the humerus in children: treatment by manipulation and extension cast. Injury. 22:451,1991. We have reviewed, at an average of 7 years, 14 children with flexion supracondylar fractures of the humerus. These fractures accounted for 6 per cent of the 288 displaced supracondylar fractures treated from 1981 to 1985. A total of 12 patients had typical fractures that were treated by manipulation and immobilization in an extension cast. Two patients had atypical fractures with anterior displacement and posterior angulation of the distal fragment; they were treated by manipulation, but were more stable when immobilized with the elbow flexed with strapping and collar and cuff support. Overall, excellent or good results were achieved in 10 cases and poor results in four cases. Of the poor results, two were due to cubitus varus. These children were the only ones under 2 years of age, and in each the deformity was due to the persistence of an abnormally large Baumann angle. Plaster immobilization was inadequate at this stage. The other two poor results were due to mild stiffness of the elbow. For typical fractures, we conclude that excellent results can be expected in most children over the age of 2 years when treated with manipulation and immobilization in extension for 3 weeks. For the rarer atypical fractures, we conclude that excellent results can be expected after manipulation and immobilization in flexion for 3 weeks. WI02. Wind WM, Schwend RM, Armstrong DG. Predicting ulnar nerve location in pinning of supracondylar humerus fractures. Journal of Pediatric Orthopedics. 22:444,2002Thirty-four consecutive patients with displaced supracondylar humerus fractures were treated with reduction and percutaneous pinning. The precise location of the ulnar nerve to the medial pin was determined by intraoperative nerve stimulation. In 22 of the 34 patients, the authors attempted to predict the location of the ulnar nerve by palpation and placing a mark on the skin. They also recorded the ability to feel the anatomic landmarks for pin fixation, including the medial epicondyle and ulnar nerve. The average distance from the medial pin to the predicted location was 9.3 mm, whereas the actual distance measured 7.6 mm, for a significant difference of 1.7 mm. Statistically, the authors could not accurately predict the location of the ulnar nerve prior to blind percutaneous crossed K-wire fixation of supracondylar humerus fractures. However, clinically they were fairly close in their prediction and documented safe insertion and distance from the nerve. Intraoperative nerve stimulation may assist in localizing the nerve prior to placement of the medial pin. Stimulation of the pin itself following insertion is another technique to ensure safe pin placement and decrease the risk of injury. ZI94. Zionts LE, McKellop HA, Hathaway R. Torsional strength of pin configurations used to fix supracondylar fractures of the humerus in children. J Bone Joint Surg [Am] 76:253,1994. Supracondylar fractures of the humerus in children are commonly treated with closed reduction and percutaneous pin fixation. Using an adult human cadaver model, we measured the resistance to internal rotation of the distal fragment of simulated supracondylar fractures, fixed with four different configurations of pins. The maximum stability was provided by two crossed pins placed from the medial and lateral condyles. In comparison, the torque required to produce 10 degrees of rotation averaged 37 per cent less with use of two lateral parallel pins and 80 per cent less with use of two lateral crossed pins (p < 0.05 for both). The average torque required to produce 10 degrees of rotation with use of three lateral pins was 25 per cent less than with use of two medial and lateral crossed pins, although the difference was not significant. ................
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