AAHS ASPN ASRM - 2013 Annual Meeting - American Association ...

Failed Darrach Procedure: an Allograft Solution
Institution where the work was prepared: Allegheny General Hospital, Pittsburgh, PA, USA
Filippos S. Giannoulis1; Jeffrey A. Greenberg, MD2; Rob W. Weiser, PA-C1; Dean G. Sotereanos1; (1)Allegheny General Hospital, (2)Indiana Hand Center
Purpose:
We describe a new technique for the treatment of painful instability of the distal ulna after Darrach procedure using an allograft as a mechanical interposition.
The purpose of the study is to evaluate the results of this technique.
Methods:
In this study we report on 17 patients who underwent revision of their Darrach procedure using an allograft (human Achilles tendon allograft). The average
age of the patients was 47 years (range 39-68) and the average time after the original procedure was 15 months. The indication for the revision surgery in all
patients was incapacitating pain over the distal stump of the ulna which increased during pronation or supination and with active grip. Pain was assessed using
a VAS (Visual Analog Scale). Grip strength was measured using a dynamometer. All patients had instability of the distal ulna, and crepitus or palpable “clicking”
during forearm rotation. Radiographs of all patients demonstrated erosion of the medial cortex of the radius, indicating impingment. Technique: 2 or 3
suture anchors were placed into the medial cortex of the radius, proximal to the sigmoid notch where the impingment occurred. An adequate amount of the
allograft was then sutured into an anchovy. The size of the allograft was determined by pronating and supinating the involved forearm with pressure applied
to the ulnar aspect of the ulna to assess crepitus. Sutures were placed through the allograft, creating a pillow-shaped spacer. Two or three drill holes were then
placed into the distal ulna for fixation of the allograft to the ulna. With final allograft placement there should be significant padding between the radius and
the ulna to prevent any palpable crepitus during forearm rotation under compression.
Results:
After an average follow-up time of 34 months all patients were re-evaluated by subjective assessment, range of motion, grip strength, pain relief and radiographs.
We report 16 patients with good and excellent results and 1 patient with persistent complaints (our first patient). There were no radiographic changes
noted.
Conclusions
The use of an allograft as a mechanical interposition between the radius and the ulna has not been described previously.With this technique there is no need
for a metallic prosthesis and as much bulk graft as necessary is obtainable. We believe that this technique is an excellent alternative to metal arthroplasty for
reconstruction of difficult cases of failed distal ulna resection.
Biomechanical Evaluation of Volar Locking Plates for Distal Radius Fractures
Institution where the work was prepared: Stony Brook University, Stony Brook, NY, USA
Scott Michael Levin, MD1; Glenn Alan Teplitz, MD2; Cory Oliver Nelson1; Jonathon Devlin Botts1; Yong Kwon1; Frederick James Serra-Hsu1; (1)Stony Brook University,
(2)Winthrop University Hospital
Introduction:
The development of fixed-angle devices have been a major advancement in orthopedic fracture care. The strength of these fixed angle constructs combined
with the benefits of using a volar approach for distal radius fractures, have made volar locking plates an attractive option for fixation of these fractures. This
study compares the biomechanical strength of two popular existing volar locking plate systems (Synthes LCP and Hand Innovations DVR) along with a nonlocking
volar T-plate (Synthes).
Methods:
Formalin-fixed cadaver forearms were used for this study. Each specimen was radiographed and any specimens with bony deformity were discarded. The specimens
were divided into 3 groups (A, B, and C) with similar bone densities based on dexascans. A completely unstable extra-articular fracture pattern was creating
using a standardized technique. Group A was fixed with the Hand Innovations DVR plate, group B with the Synthes LCP plate, and group C with the
Synthes non-locking T-plate. A materials testing machine was used to load each specimen in axial compression with 2000 cycles of 400 Newtons, representing
the physiologic loads created by flexion of all of the digits during the post-operative rehabilitation period as determined by previous studies. Stiffness, yield
point, and ultimate strength were recorded for each construct.
Results:
Each of the fixed-angle constructs completed 2000 cycles, whereas the non-locking plate failed at an average of 560 cycles. The mean stiffness of the Hand
Innovations DVR plate, Synthes LCP plate, and the Synthes non-locking plate was 277.00 N/mm, 343.17 N/mm, and 175.67 N/mm, respectively. There was a
statistically significant difference between both fixed-angle constructs and the non-locking plate (p