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

PURPOSE OF THE 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.

MATERIAL: 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.

METHODS: 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.

DISCUSSION: 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.

CONCLUSIONS: 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.