The Motec cementless modular metal-on-metal ball-and-socket
wrist arthroplasty was implanted in 16 wrists with scaphoid nonunion
advanced collapse (SNAC; grades 3 or 4) and 14 wrists with scapholunate
advanced collapse (SLAC) in 30 patients (20 men) with severe (grades
3 or 4) post-traumatic osteoarthritis of the wrist. The mean age of
the patients was 52 years (31 to 71). All prostheses integrated
well radiologically. At a mean follow-up of 3.2 years (1.1 to 6.1)
no luxation or implant breakage occurred. Two wrists were converted
to an arthrodesis for persistent pain. Loosening occurred in one
further wrist at five years post-operatively. The remainder demonstrated close
bone–implant contact. The clinical results were good, with markedly
decreased Disabilities of the Arm Shoulder and Hand (DASH) and pain
scores, and increased movement and grip strength. No patient used
analgesics and most had returned to work. Good short-term function was achieved using this wrist arthroplasty
in a high-demand group of patients with post-traumatic osteoarthritis.
Intraspinal re-implantation after traumatic avulsion of the brachial plexus is a relatively new technique. Three different approaches to the spinal cord have been described to date, namely the posterior scapular, anterolateral interscalenic multilevel oblique corpectomy and the pure lateral. We describe an anatomical study of the pure lateral approach, based on our clinical experience and studies on cadavers.
Between 1996 and 2008, nine patients with severe post-traumatic arthritis underwent revision of a failed interposition arthroplasty of the elbow with a further interposition procedure using an allograft of tendo Achillis at a mean of 5.6 years (0.7 to 13.1) after the initial procedure. There were eight men and one woman with a mean age of 47 years (36 to 56). The mean follow-up was 4.7 years (2 to 8). The mean Mayo Elbow Performance score improved from 49 (15 to 65) pre-operatively to 73 (55 to 95) (p = 0.04). The mean Disability of the Arm, Shoulder and Hand score was 26 (7 to 42). One patient was unavailable for clinical follow-up and one underwent total elbow replacement three months post-operatively. Of the remaining patients, one had an excellent, two had good, three fair and one a poor result. Subjectively, five of the nine patients were satisfied. Four continued manual labour. Revision interposition arthroplasty is an option for young, active patients with severe post-traumatic arthritis who require both mobility and durability of the elbow.
Reversed shoulder prostheses are increasingly being used for the treatment of glenohumeral arthropathy associated with a deficient rotator cuff. These non-anatomical implants attempt to balance the joint forces by means of a semi-constrained articular surface and a medialised centre of rotation. A finite element model was used to compare a reversed prosthesis with an anatomical implant. Active abduction was simulated from 0° to 150° of elevation. With the anatomical prosthesis, the joint force almost reached the equivalence of body weight. The joint force was half this for the reversed prosthesis. The direction of force was much more vertically aligned for the reverse prosthesis, in the first 90° of abduction. With the reversed prosthesis, abduction was possible without rotator cuff muscles and required 20% less deltoid force to achieve it. This force analysis confirms the potential mechanical advantage of reversed prostheses when rotator cuff muscles are deficient.
We retrospectively reviewed 21 patients (22 shoulders) who presented with deep infection after surgery to the shoulder, 17 having previously undergone hemiarthroplasty and five open repair of the rotator cuff. Nine shoulders had undergone previous surgical attempts to eradicate their infection. The diagnosis of infection was based on a combination of clinical suspicion (16 shoulders), positive frozen sections (>
5 polymorphonuclear leukocytes per high-power field) at the time of revision (15 shoulders), positive intra-operative cultures (18 shoulders) or the pre-operative radiological appearances. The patients were treated by an extensive debridement, intravenous antibiotics, and conversion to a reverse shoulder prosthesis in either a single- (10 shoulders) or a two-stage (12 shoulders) procedure. At a mean follow-up of 43 months (25 to 66) there was no evidence of recurrent infection. All outcome measures showed statistically significant improvements. Mean abduction improved from 36.1° (