Percutaneous Plate Fixation: Right for Every Surgeon?

To the Editor:

After reading the article “Percutaneous Plate Fixation of Two- and Three-part Proximal Humerus Fractures” (31[3]:237-242) by Drs Robert Gallo, Thomas Hughes, and Gregory Altman, I would be cautious in attempting the surgical technique described, as placing the plate along the lateral border of the humerus without direct visualization of the axillary nerve can be fraught with potential complication. Additionally, the percutaneous placement of screws with the danger of entanglement of the axillary nerve is concerning.

While I am sure that in the hands of an experienced shoulder/elbow surgeon and/or traumatologist this can be done safely and effectively, recommending this to the general orthopedic surgeon can be potentially hazardous. I would argue that a well-performed deltopectoral approach can be safely done, keeping the axillary nerve out of harm’s way and allowing for direct visualization of the fracture fragments. The advantage of this approach is that it allows for access to the rotator cuff. The placement of tagging sutures in the rotator cuff can be used to reinforce fixation of the fracture by passing the sutures through the plate and augmenting the fixation of the plate and screws. While some patients are concerned about cosmesis after a proximal humerus fracture, I find that the majority of patients are most interested in gaining the greatest amount of function back with the avoidance of any nerve injury, stiffness, malunion, or nonunion.

Joseph A. Abboud, MD
Philadelphia, Pennsylvania

Reply:

We agree that the goal of treating any fracture, especially proximal humerus fractures, is to maximize functional outcome while minimizing adverse events such as nerve injury, stiffness, malunion, nonunion, and avascular necrosis. Based on AO principles and available data regarding proximal humerus fractures and patient outcomes, our treatment of these fractures is based on 1) obtaining secure and accurate fixation of all fracture fragments, particularly the greater tuberosity, and torn tendons; 2) limiting the amount of soft tissue stripping and disruption to the local vascularity; and 3) initiating early motion. Cosmesis is a secondary benefit of minimally invasive fracture fixation. For most proximal humerus fractures, no surgical scar (ie, nonoperative treatment) yields superior cosmetic results to any surgical intervention.

During the past 5 years, we have gradually shifted our surgical approach from deltopectoral to a minimally invasive lateral incision. Frustrated by the difficulty of obtaining satisfactory fracture reduction and the amount of soft tissue stripping and retraction necessary to gain exposure with a deltopectoral approach, we began making an accessory lateral incision.¹ This smaller lateral incision afforded us better visualization of the greater tuberosity, which is usually posteriorly and superiorly displaced, and the rotator cuff tendons, which are torn or avulsed in 40% of these patients.² We also found that due to the contour of most available locking proximal humerus plates, proper positioning of the plate was facilitated by using this accessory incision.

More recently, we have adopted the percutaneous approach originally presented by Laflamme et al.³ Before we performed this technique in patients, we honed our skills on several cadaveric specimens and determined safe methods of inserting the plate and screw construct.⁴ Several studies have detailed the course of the axillary nerve about the proximal humerus,^5-7 while others have mapped out safe zones for screw placement of the 2 most frequently used proximal humeral locking plates.^8,9 These studies and our experience allowed us to develop a technique similar to the one described by Laflamme et al.¹⁰

Like most operative procedures, meticulous technique and caution are required to prevent iatrogenic injury to the axillary nerve during percutaneous plating of the proximal humeral fractures. We reiterate several tips that facilitate safe placement of the plate and screws. The most important initial step in the procedure is to identify the axillary nerve. The superior mini-lateral incision should be deep to the subdeltoid bursa, ie, to the level of the periosteum. Using this incision, the surgeon can palpate the axillary nerve on the undersurface of the deltoid distally. If scarring or hematoma prevents palpation of the nerve, the surgeon can consider extending the incision and directly identifying the nerve using a technique described by Robinson et al.¹¹ The plate should only be inserted after the fracture has been reduced and the nerve identified. The plate is inserted directly onto the lateral aspect of the humerus while a finger from the surgeon’s other hand retracts the axillary nerve out of harm’s way. Screws are placed with the same meticulous technique with which all percutaneous screws are placed: skin incision, blunt dissection, and identification of the bone. No screw should be prepared or inserted if soft tissue is interposed between the drill or screw tip and the bone. Dangerous screw holes such as those outlined in the literature should be avoided.^8,9 The surgeon should be protecting and palpating the nerve throughout the course of the procedure to prevent iatrogenic injury. We, like the other published series of which we are aware,¹⁰ have not had any cases of iatrogenic nerve injury using this technique.

While the deltopectoral approach is the most frequently used interval to expose proximal humerus fractures, this method has significant disadvantages. Complete exposure of all fracture fragments is often difficult using this anterior interval. Often, the greater tuberosity fragment is externally rotated by the teres minor and infraspinatus tendons and must be retrieved from the posterior shoulder. Poor outcomes have been attributed to malreduction of this fragment.^12-14 To visualize the greater tuberosity and insert the plate, extensive soft tissue stripping and at least partial release of the deltoid origin or insertion and/or the pectoralis major insertion must be performed. In addition, the anterior humeral circumflex artery, which courses along the inferior border of the subscapularis and lateral border of the bicipital groove, can be jeopardized by this exposure. Injury to this vessel, which serves as the principal blood supply to the humeral head,¹⁵ can cause avascular necrosis of the humeral head. Finally, nerve injury and muscle atrophy following proximal humerus fractures can also occur using the deltopectoral approach.^16,17 Visser et al¹⁷ reported that electromyography-detected nerve injury was present in up to 82% of displaced proximal humerus fractures treated operatively and nonoperatively; the axillary nerve was injured in 58%.

The success of any procedure is based on the ultimate functional outcome of patients. As locked plating is a recent technological advancement, few studies are available to evaluate the effectiveness of locked plating in the treatment of proximal humerus fractures. Among published studies with a minimum 1-year follow-up, percutaneous locked plating yielded an equivalent or higher functional score than locked plating performed through a deltopectoral approach (Table).^10,16,18,19 Furthermore, the operative time was reduced (53 minutes for percutaneous vs 86 minutes for deltopectoral), and complications such as avascular necrosis and nerve injury were no more likely to occur with a minimal lateral incision.^10,18

We appreciate that a degree of skepticism is applied to any new technique, especially those that require limited exposure (eg, iliosacral screws, arthroscopic Bankart repairs). However, while more studies are needed, percutaneous locked plating for proximal humerus fractures offers rigid fixation without extensive soft tissue stripping and thus may allow for earlier range of motion and improved function compared to other methods. As with any surgical procedure, meticulous technique and attention to detail are necessary to avoid devastating iatrogenic injury when using this percutaneous technique.

Robert A. Gallo, MD
Gregory T. Altman, MD
Pittsburgh, Pennsylvania

References

1. Gallo RA, Zeiders GJ, Altman GT. Two-incision technique for treatment of complex proximal humerus fractures. J Orthop Trauma. 2005; 19(10):734-740.
2. Gallo RA, Sciulli R, Daffner RH, Altman DT, Altman GT. Defining the relationship between rotator cuff injury and proximal humerus fractures. Clin Orthop Relat Res. 2007; (458):70-77.
3. Laflamme GY, Berry G, Benoit B. Percutaneous plating of the proximal humerus: a prospective multi-center clinical trial. Poster presented at: 21st Annual Meeting of the Orthopaedic Trauma Association; October 20-22, 2005; Ottawa, Canada.
4. Gallo RA, Altman GT. Evaluation of the safety of percutaneous plate fixation of the proximal humerus. Paper presented at: 19th Congress of the European Society for Surgery of the Shoulder and Elbow; September 23, 2005; Rome, Italy.
5. Cetik O, Uslu M, Acar HI, Comert A, Tekdemir I, Cift H. Is there a safe area for the axillary nerve in the deltoid muscle? A cadaveric study. J Bone Joint Surg Am. 2006; 88(11):2395-2399.
6. Bono CM, Grossman MG, Hochwald N, Tornetta P III. Radial and axillary nerves. Anatomic considerations for humeral fixation. Clin Orthop Relat Res. 2000; (373):259-264.
7. Burkhead WZ, Scheinberg RR, Bos G. Surgical anatomy of the axillary nerve. J Shoulder Elbow Surg. 1992; (1):31-36.
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11. Robinson CM, Khan L, Akhtar A, Whitaker R. The extended deltoid-splitting approach to the proximal humerus. J Orthop Trauma. 2007; 21(9):657-662.
12. Keene JS, Huizenga RE, Engber WD, Rogers SC. Proximal humeral fractures: a correlation of residual deformity with long-term function. Orthopedics. 1983; 6:173-178.
13. Cofield RH. Comminuted fractures of the proximal humerus. Clin Orthop Relat Res. 1988; (230):49-57.
14. Hessmann M, Baumgaertel F, Gehling H, Klingelhoeffer I, Gotzen L. Plate fixation of proximal humeral fractures with indirect reduction: surgical technique and results utilizing three shoulder scores. Injury. 1999; 30(7):453-462.
15. Gerber C, Schneeberger AG, Vinh TS. The arterial vascularization of the humeral head. An anatomical study. J Bone Joint Surg Am. 1990; 72(10):1486-1494.
16. Fankhauser F, Boldin C, Schippinger G, Haunschmid C, Szyszkowitz R. A new locking plate for unstable fractures of the proximal humerus. Clin Orthop Relat Res. 2005; (430):176-181.
17. Visser CP, Coene LN, Brand R, Tavy DL. Nerve lesions in proximal humeral fractures. J Shoulder Elbow Surg. 2001; 10(5):421-427.
18. Hepp P, Theopold J, Voigt C, Engel T, Josten C, Lill H. The surgical approach for locking plate osteosynthesis of displaced proximal humeral fractures influences the functional outcome. J Shoulder Elbow Surg. 2008; 17(1):21-28.
19. Björkenheim JM, Pajarinen J, Savolainen V. Internal fixation of proximal humeral fractures with a locking compression plate: a retrospective evaluation of 72 patients followed for a minimum of 1 year. Acta Orthop Scand. 2004; 75(6):741-745.