We hypothesised that a large acromial cover with
an upwardly tilted glenoid fossa would be associated with degenerative
rotator cuff tears (RCTs), and conversely, that a short acromion
with an inferiorly inclined glenoid would be associated with glenohumeral
osteoarthritis (OA). This hypothesis was tested using a new radiological parameter,
the critical shoulder angle (CSA), which combines the measurements
of inclination of the glenoid and the lateral extension of the acromion
(the acromion index). The CSA was measured on standardised radiographs of three groups:
1) a control group of 94 asymptomatic shoulders with normal rotator
cuffs and no OA; 2) a group of 102 shoulders with MRI-documented
full-thickness RCTs without OA; and 3) a group of 102 shoulders
with primary OA and no RCTs noted during total shoulder replacement.
The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0°
(29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in
the OA group. Of patients with a CSA >
35°, 84% were in the RCT
group and of those with a CSA <
30°, 93% were in the OA group. We therefore concluded that primary glenohumeral OA is associated
with significantly smaller degenerative RCTs with significantly
larger CSAs than asymptomatic shoulders without these pathologies.
These findings suggest that individual quantitative anatomy may
imply biomechanics that are likely to induce specific types of degenerative
joint disorders. Cite this article:
Instability after arthroplasty of the shoulder
is difficult to correct surgically. Soft-tissue procedures and revision surgery
using unconstrained anatomical components are associated with a
high rate of failure. The purpose of this study was to determine
the results of revision of an unstable anatomical shoulder arthroplasty
to a reverse design prosthesis. Between 2004 and 2007, 33 unstable
anatomical shoulder arthroplasties were revised to a reverse design.
The mean age of the patients was 71 years (53 to 86) and their mean
follow-up was 42 months (25 to 71). The mean time to revision was
26 months (4 to 164). Pain scores improved significantly (pre-operative
visual analogue scale (VAS) of 7.2 ( Cite this article:
We have previously described the short-term outcome of the use of reverse shoulder arthroplasty in the treatment of acute complex proximal humeral fractures in the elderly. We now report the clinical and radiological outcome of 36 fractures at a mean of 6.6 years (1 to 16). Previously, at a mean follow-up of 6 years (1 to 12) the mean Constant score was 58.5; this was reduced to 53 points with the further follow-up. A total of 23 patients (63%) had radiological evidence of loosening of the glenoid component. Nevertheless, only one patient had aseptic loosening of the baseplate at 12 years’ follow-up. The reduction in the mean Constant score with longer follow-up and the further development of scapular notching is worrying. New developments in design, bearing surfaces and surgical technique, and further follow-up, will determine whether reverse shoulder arthroplasty has a place in the management of complex proximal humeral fractures in the elderly.
In a prospective study between 2000 and 2005, 22 patients with primary osteoarthritis of the shoulder had a total shoulder arthroplasty with a standard five-pegged glenoid component, 12 with non-offset humeral head and ten with offset humeral head components. Over a period of 24 months the relative movement of the glenoid component with respect to the scapula was measured using radiostereometric analysis. Nine glenoids needed reaming for erosion. There was a significant increase in rotation about all three axes with time (p <
0.001), the largest occurring about the longitudinal axis (anteversion-retroversion), with mean values of 3.8° and 1.9° for the non-offset and offset humeral head eroded subgroups, respectively. There was also a significant difference in rotation about the anteversion-retroversion axis (p = 0.01) and the varus-valgus (p <
0.001) z-axis between the two groups. The offset humeral head group reached a plateau at early follow-up with rotation about the z-axis, whereas the mean of the non-offset humeral head group at 24 months was three times greater than that of the offset group accounting for the highly significant difference between them.
In a prospective, randomised study on the repair of tears of the rotator cuff we compared the clinical results of two suture techniques for which different suture materials were used. We prospectively randomised 100 patients with tears of the rotator cuff into two groups. Group 1 had transosseous repair with No. 3 Ethibond using modified Mason-Allen sutures and group 2 had transosseous repair with 1.0 mm polydioxanone cord using modified Kessler sutures. After 24 to 30 months the patients were evaluated clinically using the Constant score and by ultrasonography. Of the 100 patients, 92 completed the study. No significant statistical difference was seen between the two groups: Constant score, 91% Overall, seven patients had complications which required revision surgery, in four for pain (two in each group) and in three for infection (two in group 1 and one in group 2).
We studied the stability of cemented all-polyethylene keeled glenoid components by radiostereometric analysis (RSA) in 16 shoulders which had received a total shoulder replacement. There were 14 women (one bilateral) and one man with a mean age of 64 years. The diagnosis was osteoarthritis in eight and rheumatoid arthritis in seven. Two of the shoulders were excluded from the RSA study because of loosening of the tantalum markers. Three tantalum markers were inserted in the glenoid socket, two in the coracoid process and two in the acromion. The polyethylene keeled glenoid component was marked with three to five tantalum markers. Conventional radiological and RSA examinations were carried out at five to seven days, at four months and at one and two years after operation. Radiolucent lines were found in all except three shoulders. Migration was most pronounced in the distal direction and exceeded 1 mm in four shoulders. In ten shoulders rotation exceeded 2° in one or more axes with retroversion/