Abstract
Introduction
Dissemination of Total hip Arthroplasty through the direct anterior approach has, depending upon one's experience and perspective, benefitted from or been plagued by aggressive marketing. Although first developed over 60 years ago it was all but unknown until the past decade. This study exams one community surgeon's experience and thus sheds light on whether the ATHA is a viable operation for all orthopaedic surgeons.
Methods
332 hips having a THA through the direct anterior approach were prospectively studied. Side and sex distribution were approximately equal; primary OA was by far the most common diagnosis. 4 hips were converted from a previous operation for fracture. No hips were excluded; all hips were replaced through the direct anterior approach.
All hips had the same HA coated, cementless triple-taper stem; a variety of cups were used. 92% of the bearings were ceramic on poly including 22% “dual mobility” design; 88% of the heads were 28 or 32 mm. A special orthopaedic table and intraoperative c-arm were used universally. Charnley Merle D'Aubigne, Harris, and WOMAC scores were obtained before surgery and annually thereafter.
Anti-embolic prophylaxis was with intraop bilateral thigh high sequential pumps, early mobilization and aspirin for most. Those patients deemed at risk received lovenox, and those already on Coumadin continued – with bridging lovenox.
Results
The mean time for surgery was 70 minutes (60 to 175); for c-arm use: 7 seconds (maximum 21). 78% went directly home after an average hospital stay of 2 days. Less than 10% required a blood transfusion.
80% had none or a leg length difference less than 5 mm. Acetabular abduction angle was within the safe zone for all hips; 1 hip was outside the anteversion safe zone. Hip scores improved significantly for all hips (p < 0.001).
There were 5 (1.5%) intra-operative complications; all were recognized and none required further treatment or modification of the usual postop regimen. 3 dislocations occurred (0.9%). 3 reoperations (0.9%) were required: 1 early (a fall and fractured femur) and 2 late (1 fall with acetabular fracture and 1 recurrent dislocation). Another fracture occurred from a fall but additional surgery was not needed.
There were 4 (1.2%) systemic complications: 1 PE, 1 UGI bleed, 1 ileus, 1 CVA. 2 patients died for reasons unrelated to the arthroplasty.
Discussion/Conclusion:
These data suggest that satisfactory or better results with few complications can be achieved through the direct anterior approach utilizing a special orthopaedic table and intraop fluoroscopy. Using an HA coated triple-taper stem there was no atraumatic loosening in this short term follow-up. C-arm time was comparatively minimal and seems to contribute to good implant positioning. The dislocation rate was low even though large head sizes were rarely employed. There were no periprosthetic infections suggesting that claims for relative soft tissue sparing may be factual.
