[Use of angle-stable implants for proximal humeral fractures: prospective study]

To evaluate and compare proximal humeral fractures treated either by plate osteosynthesis with angular-stable screws or by intramedullary nailing, and to define the indications optimal for use of either technique.

The study comprised 97 patients. The proximal humeral internal locking system (PHILOS) plate was used in 49 patients (31 women and 18 men); with age average 57.4 years (women, 64.5 and men, 45.3 years). By the AO classification, 12 patients with type A, 15 with type B, and 22 with type C fractures. The Targon PH nail was used in 48 patients (32 women and 16 men) at an average age of 65.3 years (women, 72.2 and men, 51.4 years). Type A fractures were in 18, type B in 18 and type C in 12 patients.

The patients were prospectively evaluated and placed into the two groups. The post-operative range of motion was assessed by the Constant-Murley (CM) score at 6 weeks, and at 3, 6 and 12 months. The CM value was related to the healthy collateral limb and recorded as a relative CM score. RESULTS In the PHILOS group, the average values were: operative time, 76.2 min; X-ray exposure, 4.2 min; and relative CM score, 74.5 points. The Targon PH group showed the average operative time of 50.2 min., X-ray exposure for 4 min. and the relative CM score 78.3 points. There were no significant differences between the groups, with the exception of shorter operative time in intramedullary nailing.

Nailing is the method of choice for two-fragment fractures. In comminutive metaphyseal fractures particularly, the use of nailing is more effective than plate osteosynthesis that carries the risk of plate detachment from the diaphysis. In fractures with a long fracture line extending into the metaphysis, plate osteosynthesis with open reduction is a better option. The results in three-fragment fractures are comparable and the choice of an implant is the matter of surgeon's preference. The standard technique for four-fragment fractures involves the use of angular-stable plate fixation through the deltoid- pectoral approach. Intramedullary nailing is a borderline indication requiring a modified surgical procedure, with tubercles being fixed with osteosuture.

No statistically significant differences in functional results occurred between the observed groups at one year of followup. In four-fragment proximal humerus fractures, the patients treated with Targon PH nails had more complications and worse relative CM scores than those treated with PHILOS plates; however, this was not statistically significant and the number of complications decreased after the technique of tubercle osteosuture had been introduced. Finally, the only significant difference between the groups was a shorter operative time with the use of intramedullary nailing.