Incidence of early radiolucent glenoid lines in patients having total shoulder replacements.

UNLABELLED: Glenoid loosening is the most common long-term complication occurring after total shoulder replacement. Imprecise cement technique and glenoid preparation may result in early radiolucent glenoid line formation. Early radiolucent lines may indicate inadequate initial fixation, which may contribute to early loosening. Improved cement techniques, refined instrumentation, and glenoid component design all may reduce early radiolucent lines. In our study, postoperative anteroposterior and axillary radiographs were obtained after 68 total shoulder replacements done by one surgeon using either an old free-hand, manual packing technique before November 1998 (n = 28) or a new instrument preparation and pressurization technique since November 1998 (n = 40). Three orthopaedic surgeons blindly reviewed the radiographs for the presence and thickness (mm) of radiolucent lines. The newer instrumented pressurization group had a lower incidence of radiolucent lines than the old manually packed group. In the new subgroup, pegged components had a lower incidence of radiolucent lines than keeled components. The incidence of radiolucent lines seems to be reduced using specially designed instruments, new glenoid designs, and modern cement techniques, which may lead to reduced long-term glenoid loosening. LEVEL OF EVIDENCE: Therapeutic study, Level III-2 (retrospective cohort study). See the Guidelines for Authors for a complete description of levels of evidence.