Humeral Locked Nails Research Articles

Assessment of Intraoperative Rotational Alignment of Closed Locked Intramedullary Nailing for Humerus Fractures.

Intramedullary nailing of humerus fractures has evolved over the past half century and has grown in popularity especially for the polytraumatized patient. The importance of restoring appropriate rotational alignment is equivalent to that of restoring sagittal and coronal alignment to decrease the risk of shoulder degenerative changes and limit range of motion discrepancy from the contralateral limb. This technique is designed to introduce an intraoperative fluoroscopic method to obtain adequate rotational alignment of humeral shaft fractures treated with closed antegrade humeral locked nailing.

The Use of Locked Nails in the Treatment of Humeral Shaft: Delayed Union and Nonunion

Objectives: To assess the results and clinical outcome of delayed union and nonunion humeral shaft treatment using locked medullary nails. Subjects and Methods: The Russel and Taylor humeral locking nail was used to treat 21 patients with humeral shaft fractures at Al Razi hospital, Kuwait, from 1997 to 2001. Of these, 8 had delayed union and 13 nonunion. Also, 13 had previous operative treatment, while 8 had nonoperative treatment. Antegrade nailing was done in all cases, and all nails were fixed statically. Autogenous iliac bone grafts were used in 17 cases. Results: Of the 21 cases of fractures, 19 were united. Only 2 cases had persistent nonunion. Eighteen cases had satisfactory shoulder function, and 3 lost shoulder abduction between 40 and 65 degrees. Conclusion: Our data showed that humeral locked nails can achieve satisfactory clinical results in treating humeral shaft delayed unions and nonunions.

Open exchange locked nailing in humeral nonunions after intramedullary nailing.

Humeral nonunions after cannulated intramedullary nailing have been difficult to reconstruct. In the current study, 23 consecutive patients were treated by open exchange locked nailing with bone grafting. There were 16 men and seven women with a mean age of 46.2 years. The nonunions followed humeral locked nailing in eight patients, Seidel nailing in 13, and Küntscher nailing in two. The average nonunion time was 14.7 months. The nonunions, located at the proximal (1/3) in four humeri, middle (1/3) in 15, and distal (1/3) in four, were antegrade nailed in 10 and retrograde nailed in 13. Nineteen had 8-mm nails and four had 7-mm nails. Supplementary wiring was used in 19 patients. The average followup was 21.4 months. With one surgery, all but one patient (96%) achieved osseous union in, on average, 16.3 weeks. One patient with chronic renal dialysis had persistent nonunion and an osteolytic supracondylar fracture. Other complications included one postoperative radial nerve palsy, one brachial artery injury, and one wire infection. At followup, all patients with solid union had excellent or satisfactory recovery of shoulder function. The average postoperative Neer score (90.7) was significantly better than the average preoperative score (68.5). Two patients had losses of elbow motion of 10 degrees and 20 degrees, respectively. This study shows that humeral nonunion after cannulated intramedullary nailing can be treated effectively by open exchange locked nailing with bone grafting. Supplementary wiring can compress the nonunion and facilitate bone healing.

Complications of locked nailing in humeral shaft fractures.

The purpose of this study was to investigate the complications of humeral locked nailing. Between 1994 and 2000, 161 humeral shaft fractures (98 acute fractures and 63 delayed unions or nonunions) in 159 patients treated with humeral locked nails were followed up for an average of 25.4 months. There were 89 men and 70 women, with an average age of 53.5 years. Acute fractures included 68 closed, 18 type I, 8 type II, 3 type IIIA, and 1 type IIIB open fractures. Thirty-six nonunions had previous operations. In general, acute fractures were treated with closed nailing and nonunions were treated with open nailing with bone grafting. Since 1998, interfragmentary wiring has been added in nonunions to compress the fracture. In total, 30 patients had 31 significant complications. Nine of them were persistent nonunions, six from acute fractures and three from nonunions. Fracture gap was associated with a significantly higher risk of nonunion. The risk of operative comminution was significantly higher in retrograde nailing, and operative comminution resulted in a significantly higher risk of nonunion. Seven of the nine nonunions underwent revisional nailing and achieved eventual union. Removal of the protruded screws was performed in two cases. Other complications included shoulder impairment, elbow impairment, angular malunion, and post-nailing radial nerve palsy. Many complications of humeral locked nailing can be prevented by improving the implant design or surgical techniques. The patients with persistent nonunion can be reliably treated by revisional nailing and bone grafting.

Locked-nail treatment of humeral surgical neck nonunions.

The authors' purpose was to report their experience with the use of locked nails in treating humeral surgical neck nonunions. Locked nailing has the advantages of minimal soft tissue trauma, automatic fracture reduction, and stable fracture fixation. Excluding 3 patients with severe medical illness, a total of 15 consecutive patients with 15 nonunions were treated by humeral locked nailing and bone grafting. Delay from trauma to surgery averaged 13.8 months, and 10 patients had previous operations. The average age of patients was 55.1 years; average follow-up time was 22.4 months. There were two hypertrophic and 13 atrophic nonunions. The average preoperative Neer score for shoulder joints was 53.5. All but three cases had varus deformity, with an average angle of 32.3 degrees. Seven nonunions were nailed with 8-mm nails and eight with 7-mm nails. With a single operation, all but one patient achieved osseous union in an average of 5.4 months. This one patient, who had a Neer score of 72, refused further surgery. At follow-up, 13 of the 15 patients had excellent or good functional recovery of shoulder joints, with an average Neer score of 86.7. Four patients had residual varus angulation averaging 15.5 degrees. For patients with solid union, the average range of shoulder motion was 152.3 degrees in flexion and 146.4 degrees in abduction. No patients had significant limitation of elbow motion. Three patients had occasional shoulder pain and no patients had evident shoulder impingement. For humeral surgical neck nonunions in which the head fragment still preserves the greater tuberosity, locked nailing with transfixing screws appeared to be a useful alternative, especially in fractures with osteoporosis, severe varus deformity, or severe soft tissue scarring.

Locked nailing with interfragmentary wiring for humeral nonunions.

Locked nailing for humeral nonunions is threatened by residual fracture gap and fracture motion. This article describes the clinical experience of using interfragmentary wiring to solve these problems. Interfragmentary wiring was used in 21 consecutive humeral nonunions treated with humeral locked nails. The average age of patients was 49.5 years, with an average nonunion duration of 14.4 months. Eighteen patients had previous operations. Nonunions were located at the proximal third in 4, the middle third in 10, and the distal third in 7. Antegrade nailing was used in 11 and retrograde nailing in 10. Sixteen nonunions were nailed with 8-mm nails and five with 7-mm nails. Interfragmentary wiring was applied to either the posterior or the lateral cortex of humeri in a figure-of-eight configuration. Bone grafting was performed in all and average follow-up time was 22 months. With a single operation, all patients achieved osseous union in, on average, 18.3 weeks. One patient with segmental nonunion suffered acute renal failure 4 months after operation, but fracture healing was not affected. Wire infection occurred in one patient with preoperative infection at the nail entry site and was treated by implant removal. Other complications including two transient radial nerve palsies and one brachial artery injury did not affect the final outcome. At follow-up, all but four patients had complete recovery of shoulder flexion and abduction. The average postoperative Neer score (91.1 points) was significantly better than the average preoperative score (65.5 points). All but three patients had complete recovery of elbow motion. Interfragmentary wiring, a safe procedure if properly performed, could effectively decrease the residual fracture gap and fracture motion in locked nailing of humeral nonunions. Further biomechanical studies and prospective, randomized, controlled studies are warranted.

Rotational alignment of humerus after closed locked nailing.

Rotational malalignment that may happen during closed nailing of humeral fractures is, to date, an unexplored area of investigation. The purpose of this study was to examine the effect of arm position during surgery on humeral rotational alignment and the effect of this alignment on shoulder motion and function. Thirty patients with eventual fracture healing after closed humeral locked nailing were retrospectively studied: 15 had retrograde nailing; 15, antegrade. Retrograde nailing was performed with the patient in a decubitus position and with the upper arm anteriorly flexed and the forearm perpendicular to the operating table. Antegrade nailing was performed with the patient in a semisitting position and with the upper arm in the so-called resting position. The humeral retroversion angle as measured by computed tomographic scan, range of shoulder rotation, and Neer score of the shoulder for the fractured and the intact humeri were determined, and the discrepancy (i.e., value for the intact subtracted from that for the fractured) between the two was noted. To test the effect on alignment of positioning during retrograde nailing, we similarly determined retroversion angles for another 15 patients treated in a supine resting position. Between antegrade nailing and retrograde nailing in decubitus position, there was a significant difference in the mean discrepancies for the retroversion angles and the range of external rotation of the shoulder in the neutral and abduction positions, but no significant difference for internal rotation of the shoulder and Neer score. Between antegrade nailing and retrograde nailing in supine resting position, there was no significant difference in the mean discrepancy for the retroversion angle. Positioning of the arm may significantly affect humeral rotational alignment and range of motion during closed nailing. Until a reliable method for intraoperative measurement of humeral rotation is devised, we recommend that closed nailing of humeral shaft fractures be performed with the patient's upper arm in the resting position shown in this study.

Treatment of humeral shaft delayed unions and nonunions with humeral locked nails.

To report experience with use of humeral locked nails in treating humeral delayed unions and nonunions. The following techniques yielded encouragingly good results: static locking, short-to-long segment nailing, bone grafting, fracture compression, and minimal surgical trauma. A total of 41 consecutive patients with 13 delayed unions and 28 nonunions were treated with humeral locked nails. Delay from trauma to surgery averaged 4.2 months for delayed union and 15.5 months for nonunion. The average age of patients was 50.2 years; average follow-up time was 23.2 months. There were 7 proximal-third fractures, 21 middle-third fractures, and 13 distal-third fractures. The antegrade approach was used for 13 fractures and retrograde for 28. Open nailing was performed in 39 fractures and closed nailing in 2. If the fracture motion was still present after nail insertion, axial compression of the fracture site was specially applied. Bone grafting was performed in the fractures with open nailing. Thirty-four fractures were nailed with 8-mm nails, and 7 fractures were nailed with 7-mm nails. With a single operation, all but two patients achieved osseous union in, on average, 5.6 months. One of these two patients eventually gained union after another surgery with fracture compression along the original nail and concurrent bone grafting. The second patient, undergoing hemodialysis for chronic renal failure, had persistent nonunion. At follow-up, for patients with antegrade nailing, all but four patients had less than 20 degrees limitation of shoulder abduction. For patients with retrograde nailing, all but two had less than 10 degrees limitation of elbow motion. Only the patient with persistent nonunion had continual pain and significant impairment of arm function. Humeral locked nailing seems to be effective for humeral delayed unions or nonunions. It may be an acceptable alternative for fractures unsuited for plate fixation, such as those with comminution, osteoporosis, or a severely adhered radial nerve.

Anatomic Considerations of Locked Humeral Nailing

To investigate the risk of axillary nerve injury by the proximal locking screws in antegrade nailing of humeral fractures, the anatomy of the axillary nerve was examined in 20 fresh anatomic specimen humeri, which subsequently were nailed antegrade with specially designed humeral locked nails. The axillary nerve was found to be on average 45.6 mm below the tip of the greater tuberosity; it was jeopardized by insertion of the lower proximal locking screw in one of the 20 specimens. Short humeri, humeri with small heads, or too deeply inserted nails may increase the risk of nerve injury; likewise, a lower location and more horizontal direction of the locking screws and a greater curvature of the nail can heighten the risk. In addition to the examination of the axillary nerve, a geometric study of these anatomic specimen was performed and was aimed at improving retrograde nailing technique and thus treatment results. The humeral geometry indicated that for the best linearity in the sagittal plane, an entry portal incorporating the superior margin of the olecranon fossa would be recommended for the 14 humeri with a distal humeral offset less than 4 mm, whereas a supracondylar entry portal would be recommended for the six humeri with an offset larger than 4 mm. For best linearity in the coronal plane, the entry portal and nailing direction should be more lateral in humeri with a smaller humeral elbow angle.

Antegrade locked nailing for humeral shaft fractures.

Treatment results of antegrade locked nailing of acute humeral shaft fractures, including union rate and recovery of shoulder function, have been inconsistent. This led the current authors to hypothesize that implant design and surgical techniques might account for this inconsistency. In the current study, 47 fractures (38 acute; nine pathologic) in 47 patients achieved union with the techniques of closed nailing, short to long segment nailing, and fracture compression. Satisfactory recovery of shoulder function occurred because of minimal surgical trauma, prevention of impingement by the nail or locking screws, and prevention of axillary nerve injury or comminution of the humeral head. Forty-seven patients with 38 acute fractures and nine pathologic fractures were treated with humeral locked nails. Mean followup time was 21.4 months. With a single operation, all 38 acute fractures proceeded to eventual union; the average time to union was 7.8 weeks. Thirty-five patients had excellent or satisfactory recovery of shoulder function. Complications included slipout of the proximal screw, nail breakage, fragment displacement, and transient postoperative radial nerve palsy. All nine patients with pathologic fractures had substantial pain relief and increased arm function after surgery. The current study shows the reliability of antegrade locked nailing for proximal and middle third fractures of the humeral shaft.

Locked Nailing for Displaced Surgical Neck Fractures of the Humerus

To report experience with a newly devised humeral locked nail for treating surgical neck fractures of the humerus. This device has the advantages of a small diameter for minimal tissue trauma and transfixing locking screws for reliable fixation. From 1993 to 1996, 21 consecutive severely displaced surgical neck fractures of the humerus were antegrade nailed with humeral locked nails; 2 fractures were associated with dislocation and 1 fracture was a comminuted metaphyseal fracture with a failed plating. The average age of patients was 65.8 years; average follow-up time was 19.2 months. The proximal screws were applied upward in 5 patients and downward in 16 patients. Static locking was performed in 8 patients, dynamic locking in 13 others. The average operation time was 55 minutes. No patients needed blood transfusion. All fractures eventually achieved union with an average time to union of 14.8 weeks. On the basis of Neer criteria for outcome analysis, excellent or satisfactory results were obtained for 86% of the patients (18 of 21 patients). No patients had deep infection, implant failure, malunion, osteonecrosis, or nail migration that interfered with joint motion. Due to technique errors, one patient had shoulder joint impingement caused by protrusion of the proximal nail tip. The operative method reported here has the advantages of minimal tissue trauma, minimal hardware application, sufficient fixation, and easy operative technique, and it can be a worthy alternative for the treatment of severely displaced surgical neck fractures of the humerus.

Treatment of Humeral Shaft Fractures by Retrograde Locked Nailing

From 1992 to 1994, 29 middle and 19 distal humeral shaft fractures (39 acute fractures, six nonunions, and three pathologic fractures) in 48 patients were treated by retrograde locked nailing. The first eight acute fractures were treated with Seidel nails, the other 40 fractures with specially designed humeral locked nails. Nails were inserted from the supracondylar (6) or the olecranon fossa (42) entry portal. With a single operation, all acute fractures and nonunions achieved osseous union without serious complications. The average time to union was 8.2 weeks for acute fractures and 14.2 weeks for nonunions. Recovery of shoulder function was complete. Elbow motion was excellent in all but one nonunion that resulted from a Type IIIB open fracture. Two patients with supracondylar entry had apex to posterior angular malunion. One patient with a distal comminuted fracture had varus malunion. Three patients had an iatrogenic bony split, but healing was unaffected. Patients with pathologic fractures maintained satisfactory arm function postoperatively. Given the few complications and good functional recovery seen in this study, retrograde locked nailing appears to be a good alternative treatment in middle and distal humeral shaft fractures. The olecranon fossa approach, with more linearity to the humerus, is preferred. In the authors' experience, humeral locked nails are inserted more easily and are associated with fewer complications than are Seidel nails.