There is little information about the management
of peri-prosthetic fracture of the humerus after total shoulder replacement
(TSR). This is a retrospective review of 22 patients who underwent
a revision of their original shoulder replacement for peri-prosthetic
fracture of the humerus with bone loss and/or loose components.
There were 20 women and two men with a mean age of 75 years (61
to 90) and a mean follow-up 42 months (12 to 91): 16 of these had
undergone a previous revision TSR. Of the 22 patients, 12 were treated
with a long-stemmed humeral component that bypassed the fracture.
All their fractures united after a mean of 27 weeks (13 to 94).
Eight patients underwent resection of the proximal humerus with
endoprosthetic replacement to the level of the fracture. Two patients
were managed with a clam-shell prosthesis that retained the original
components. The mean Oxford shoulder score (OSS) of the original
TSRs before peri-prosthetic fracture was 33 (14 to 48). The mean
OSS after revision for fracture was 25 (9 to 31). Kaplan-Meier survival
using re-intervention for any reason as the endpoint was 91% (95%
confidence interval (CI) 68 to 98) and 60% (95% CI 30 to 80) at
one and five years, respectively. There were two revisions for dislocation of the humeral head,
one open reduction for modular humeral component dissociation, one
internal fixation for nonunion, one trimming of a prominent screw
and one re-cementation for aseptic loosening complicated by infection,
ultimately requiring excision arthroplasty. Two patients sustained
nerve palsies. Revision TSR after a peri-prosthetic humeral fracture associated
with bone loss and/or loose components is a salvage procedure that
can provide a stable platform for elbow and hand function. Good
rates of union can be achieved using a stem that bypasses the fracture.
There is a high rate of complications and function is not as good as
with the original replacement.
Between 1976 and 2004, 38 revision arthroplasties (35 patients) were performed for aseptic loosening of the humeral component. The mean interval from primary arthroplasty to revision was 7.1 years (0.4 to 16.6). A total of 35 shoulders (32 patients) were available for review at a mean follow-up of seven years (2 to 19.3). Pre-operatively, 34 patients (97%) had moderate or severe pain; at final follow-up, 29 (83%) had no or only mild pain (p <
0.0001). The mean active abduction improved from 88° to 107° (p <
0.01); and the mean external rotation from 37° to 46° (p = 0.27). Excellent or satisfactory results were achieved in 25 patients (71%) according to the modified Neer rating system. Humeral components were cemented in 29, with ingrowth implants used in nine cases. There were 19 of standard length and 17 were longer (two were custom replacements and are not included). Bone grafting was required for defects in 11 humeri. Only two glenoid components were left unrevised. Intra-operative complications included cement extrusion in eight cases, fracture of the shaft of the humerus is two and of the tuberosity in four. There were four re-operations, one for recurrent humeral loosening, with 89% survival free of re-operations at ten years. Revision surgery for aseptic loosening of the humeral component provides reliable pain relief and modest improvement of movement, although there is a substantial risk of intra-operative complications. Revision to a total shoulder replacement gives better results than to a hemiarthroplasty.